@article{cosgrove_dupree_gomez_haigler_kubicki_zimmer_2024, title={How Many Glucan Chains Form Plant Cellulose Microfibrils? A Mini Review}, volume={8}, ISSN={["1526-4602"]}, url={https://doi.org/10.1021/acs.biomac.4c00995}, DOI={10.1021/acs.biomac.4c00995}, abstractNote={Assessing the number of glucan chains in cellulose microfibrils (CMFs) is crucial for understanding their structure-property relationships and interactions within plant cell walls. This Review examines the conclusions and limitations of the major experimental techniques that have provided insights into this question. Small-angle X-ray and neutron scattering data predominantly support an 18-chain model, although analysis is complicated by factors such as fibril coalescence and matrix polysaccharide associations. Solid-state nuclear magnetic resonance (NMR) spectroscopy allows the estimation of the CMF width from the ratio of interior to surface glucose residues. However, there is uncertainty in the assignment of NMR spectral peaks to surface or interior chains. Freeze-fracture transmission electron microscopy images show cellulose synthase complexes to be "rosettes" of six lobes each consistent with a trimer of cellulose synthase enzymes, consistent with the synthesis of 18 parallel glucan chains in the CMF. Nevertheless, the number of chains in CMFs remains to be conclusively demonstrated.}, journal={BIOMACROMOLECULES}, author={Cosgrove, Daniel J. and Dupree, Paul and Gomez, Enrique D. and Haigler, Candace H. and Kubicki, James D. and Zimmer, Jochen}, year={2024}, month={Aug} }
 @article{kwansa_singh_williams_haigler_roberts_yingling_2024, title={Structural determination of a full-length plant cellulose synthase informed by experimental and in silico methods}, volume={1}, ISSN={["1572-882X"]}, DOI={10.1007/s10570-023-05691-x}, journal={CELLULOSE}, author={Kwansa, Albert L. and Singh, Abhishek and Williams, Justin T. and Haigler, Candace H. and Roberts, Alison W. and Yingling, Yaroslava G.}, year={2024}, month={Jan} }
 @article{graham_park_billings_hulse-kemp_haigler_lobaton_2022, title={Efficient imaging and computer vision detection of two cell shapes in young cotton fibers}, volume={11}, ISSN={["2168-0450"]}, url={https://doi.org/10.1002/aps3.11503}, DOI={10.1002/aps3.11503}, abstractNote={AbstractPremiseThe shape of young cotton (Gossypium) fibers varies within and between commercial cotton species, as revealed by previous detailed analyses of one cultivar of G. hirsutum and one of G. barbadense. Both narrow and wide fibers exist in G. hirsutum cv. Deltapine 90, which may impact the quality of our most abundant renewable textile material. More efficient cellular phenotyping methods are needed to empower future research efforts.MethodsWe developed semi‐automated imaging methods for young cotton fibers and a novel machine learning algorithm for the rapid detection of tapered (narrow) or hemisphere (wide) fibers in homogeneous or mixed populations.ResultsThe new methods were accurate for diverse accessions of G. hirsutum and G. barbadense and at least eight times more efficient than manual methods. Narrow fibers dominated in the three G. barbadense accessions analyzed, whereas the three G. hirsutum accessions showed a mixture of tapered and hemisphere fibers in varying proportions.DiscussionThe use or adaptation of these improved methods will facilitate experiments with higher throughput to understand the biological factors controlling the variable shapes of young cotton fibers or other elongating single cells. This research also enables the exploration of links between early cell shape and mature cotton fiber quality in diverse field‐grown cotton accessions.}, journal={APPLICATIONS IN PLANT SCIENCES}, author={Graham, Benjamin P. and Park, Jeremy and Billings, Grant T. and Hulse-Kemp, Amanda M. and Haigler, Candace H. and Lobaton, Edgar}, year={2022}, month={Nov} }
 @article{restrepo-montoya_hulse-kemp_scheffler_haigler_hinze_love_percy_jones_frelichowski_2022, title={Leveraging National Germplasm Collections to Determine Significantly Associated Categorical Traits in Crops: Upland and Pima Cotton as a Case Study}, volume={13}, ISSN={["1664-462X"]}, url={http://dx.doi.org/10.3389/fpls.2022.837038}, DOI={10.3389/fpls.2022.837038}, abstractNote={Observable qualitative traits are relatively stable across environments and are commonly used to evaluate crop genetic diversity. Recently, molecular markers have largely superseded describing phenotypes in diversity surveys. However, qualitative descriptors are useful in cataloging germplasm collections and for describing new germplasm in patents, publications, and/or the Plant Variety Protection (PVP) system. This research focused on the comparative analysis of standardized cotton traits as represented within the National Cotton Germplasm Collection (NCGC). The cotton traits are named by ‘descriptors’ that have non-numerical sub-categories (descriptor states) reflecting the details of how each trait manifests or is absent in the plant. We statistically assessed selected accessions from three major groups ofGossypiumas defined by the NCGC curator: (1) “Stoneville accessions (SA),” containing mainly Upland cotton (Gossypium hirsutum) cultivars; (2) “Texas accessions (TEX),” containing mainlyG. hirsutumlandraces; and (3)Gossypium barbadense(Gb), containing cultivars or landraces of Pima cotton (Gossypium barbadense). For 33 cotton descriptors we: (a) revealed distributions of character states for each descriptor within each group; (b) analyzed bivariate associations between paired descriptors; and (c) clustered accessions based on their descriptors. The fewest significant associations between descriptors occurred in the SA dataset, likely reflecting extensive breeding for cultivar development. In contrast, the TEX and Gb datasets showed a higher number of significant associations between descriptors, likely correlating with less impact from breeding efforts. Three significant bivariate associations were identified for all three groups,bract nectaries:boll nectaries,leaf hair:stem hair, andlint color:seed fuzz color. Unsupervised clustering analysis recapitulated the species labels for about 97% of the accessions. Unexpected clustering results indicated accessions that may benefit from potential further investigation. In the future, the significant associations between standardized descriptors can be used by curators to determine whether new exotic/unusual accessions most closely resemble Upland or Pima cotton. In addition, the study shows how existing descriptors for large germplasm datasets can be useful to inform downstream goals in breeding and research, such as identifying rare individuals with specific trait combinations and targeting breakdown of remaining trait associations through breeding, thus demonstrating the utility of the analytical methods employed in categorizing germplasm diversity within the collection.}, journal={FRONTIERS IN PLANT SCIENCE}, publisher={Frontiers Media SA}, author={Restrepo-Montoya, Daniel and Hulse-Kemp, Amanda M. and Scheffler, Jodi A. and Haigler, Candace H. and Hinze, Lori L. and Love, Janna and Percy, Richard G. and Jones, Don C. and Frelichowski, James}, year={2022}, month={Apr} }
 @article{graham_haigler_2021, title={Microtubules exert early, partial, and variable control of cotton fiber diameter}, volume={253}, ISSN={["1432-2048"]}, url={https://doi.org/10.1007/s00425-020-03557-1}, DOI={10.1007/s00425-020-03557-1}, abstractNote={Variable cotton fiber diameter is set early in anisotropic elongation by cell-type-specific processes involving the temporal and spatial regulation of microtubules in the apical region. Cotton fibers are single cells that originate from the seed epidermis of Gossypium species. Then, they undergo extreme anisotropic elongation and limited diametric expansion. The details of cellular morphogenesis determine the quality traits that affect fiber uses and value, such as length, strength, and diameter. Lower and more consistent diameter would increase the competitiveness of cotton fiber with synthetic fiber, but we do not know how this trait is controlled. The complexity of the question is indicated by the existence of fibers in two major width classes in the major commercial species: broad and narrow fibers exist in commonly grown G. hirsutum, whereas G. barbadense produces only narrow fiber. To further understand how fiber diameter is controlled, we used ovule cultures, morphology measurements, and microtubule immunofluorescence to observe the effects of microtubule antagonists on fiber morphology, including shape and diameter within 80 µm of the apex. The treatments were applied at either one or two days post-anthesis during different stages of fiber morphogenesis. The results showed that inhibiting the presence and/or dynamic activity of microtubules caused larger diameter tips to form, with greater effects often observed with earlier treatment. The presence and geometry of a microtubule-depleted-zone below the apex were transiently correlated with the apical diameter of the narrow tip types. Similarly, the microtubule antagonists had somewhat different effects between tip types. Overall, the results demonstrate cell-type-specific mechanisms regulating fiber expansion within 80 µm of the apex, with variation in the impact of microtubules between tip types and over developmental time.}, number={2}, journal={PLANTA}, publisher={Springer Science and Business Media LLC}, author={Graham, Benjamin P. and Haigler, Candace H.}, year={2021}, month={Jan} }
 @article{burris_makarem_slabaugh_chaves_pierce_lee_kiemle_kwansa_singh_yingling_et al._2021, title={Phenotypic effects of changes in the FTVTxK region of an Arabidopsis secondary wall cellulose synthase compared with results from analogous mutations in other isoforms}, volume={5}, ISSN={["2475-4455"]}, url={https://doi.org/10.1002/pld3.335}, DOI={10.1002/pld3.335}, abstractNote={AbstractUnderstanding protein structure and function relationships in cellulose synthase (CesA), including divergent isomers, is an important goal. Here, we report results from mutant complementation assays that tested the ability of sequence variants of AtCesA7, a secondary wall CesA of Arabidopsis thaliana, to rescue the collapsed vessels, short stems, and low cellulose content of the irx3‐1 AtCesA7 null mutant. We tested a catalytic null mutation and seven missense or small domain changes in and near the AtCesA7 FTVTSK motif, which lies near the catalytic domain and may, analogously to bacterial CesA, exist within a substrate “gating loop.” A low‐to‐high gradient of rescue occurred, and even inactive AtCesA7 had a small positive effect on stem cellulose content but not stem elongation. Overall, secondary wall cellulose content and stem length were moderately correlated, but the results were consistent with threshold amounts of cellulose supporting particular developmental processes. Vibrational sum frequency generation microscopy allowed tissue‐specific analysis of cellulose content in stem xylem and interfascicular fibers, revealing subtle differences between selected genotypes that correlated with the extent of rescue of the collapsing xylem phenotype. Similar tests on PpCesA5 from the moss Physcomitrium (formerly Physcomitrella) patens helped us to synergize the AtCesA7 results with prior results on AtCesA1 and PpCesA5. The cumulative results show that the FTVTxK region is important for the function of an angiosperm secondary wall CesA as well as widely divergent primary wall CesAs, while differences in complementation results between isomers may reflect functional differences that can be explored in further work.}, number={8}, journal={PLANT DIRECT}, publisher={Wiley}, author={Burris, Jason N. and Makarem, Mohamadamin and Slabaugh, Erin and Chaves, Arielle and Pierce, Ethan T. and Lee, Jongcheol and Kiemle, Sarah N. and Kwansa, Albert L. and Singh, Abhishek and Yingling, Yaroslava G. and et al.}, year={2021}, month={Aug} }
 @article{singh_kwansa_kim_williams_yang_li_kubicki_roberts_haigler_yingling_2020, title={In silico structure prediction of full-length cotton cellulose synthase protein (GhCESA1) and its hierarchical complexes}, volume={27}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-020-03194-7}, DOI={10.1007/s10570-020-03194-7}, number={10}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Singh, Abhishek and Kwansa, Albert L. and Kim, Ho Shin and Williams, Justin T. and Yang, Hui and Li, Nan K. and Kubicki, James D. and Roberts, Alison W. and Haigler, Candace H. and Yingling, Yaroslava G.}, year={2020}, month={Apr}, pages={5597–5616} }
 @article{pierce_graham_stiff_osborne_haigler_2019, title={Cultures of Gossypium barbadense cotton ovules offer insights into the microtubule-mediated control of fiber cell expansion}, volume={249}, ISSN={0032-0935 1432-2048}, url={http://dx.doi.org/10.1007/s00425-019-03106-5}, DOI={10.1007/s00425-019-03106-5}, abstractNote={A novel method for culturing ovules of Gossypium barbadense allowed in vitro comparisons with Gossypium hirsutum and revealed variable roles of microtubules in controlling cotton fiber cell expansion. Cotton fibers undergo extensive elongation and secondary wall thickening as they develop into our most important renewable textile material. These single cells elongate at the apex as well as elongating and expanding in diameter behind the apex. These multiple growth modes represent an interesting difference compared to classical tip-growing cells that needs to be explored further. In vitro ovule culture enables experimental analysis of the controls of cotton fiber development in commonly grown Gossypium hirsutum cotton, but, previously, there was no equivalent system for G. barbadense, which produces higher quality cotton fiber. Here, we describe: (a) how to culture the ovules of G. barbadense successfully, and (b) the results of an in vitro experiment comparing the role of microtubules in controlling cell expansion in different zones near the apex of three types of cotton fiber tips. Adding the common herbicide fluridone, 1-Methyl-3-phenyl-5-[3-(trifluoromethyl)phenyl]-4(1H)-pyridinone, to the medium supported G. barbadense ovule culture, with positive impacts on the number of useful ovules and fiber length. The effect is potentially mediated through inhibited synthesis of abscisic acid, which antagonized the positive effects of fluridone. Fiber development was perturbed by adding colchicine, a microtubule antagonist, to ovules of G. barbadense and G. hirsutum cultured 2 days after flowering. The results supported the zonal control of cell expansion in one type of G. hirsutum fiber tip and highlighted differences in the role of microtubules in modulating cell expansion between three types of cotton fiber tips.}, number={5}, journal={Planta}, publisher={Society for Mining, Metallurgy and Exploration Inc.}, author={Pierce, Ethan T. and Graham, Benjamin P. and Stiff, Michael R. and Osborne, Jason A. and Haigler, Candace H.}, year={2019}, month={Feb}, pages={1551–1563} }
 @article{scavuzzo-duggan_chaves_singh_sethaphong_slabaugh_yingling_haigler_roberts_2018, title={Cellulose synthase "class specific regions' are intrinsically disordered and functionally undifferentiated}, volume={60}, ISSN={["1744-7909"]}, url={https://publons.com/wos-op/publon/28057448/}, DOI={10.1111/jipb.12637}, abstractNote={AbstractCellulose synthases (CESAs) are glycosyltransferases that catalyze formation of cellulose microfibrils in plant cell walls. Seed plant CESA isoforms cluster in six phylogenetic clades, whose non‐interchangeable members play distinct roles within cellulose synthesis complexes (CSCs). A ‘class specific region’ (CSR), with higher sequence similarity within versus between functional CESA classes, has been suggested to contribute to specific activities or interactions of different isoforms. We investigated CESA isoform specificity in the moss, Physcomitrella patens (Hedw.) B. S. G. to gain evolutionary insights into CESA structure/function relationships. Like seed plants, P. patens has oligomeric rosette‐type CSCs, but the PpCESAs diverged independently and form a separate CESA clade. We showed that P. patens has two functionally distinct CESAs classes, based on the ability to complement the gametophore‐negative phenotype of a ppcesa5 knockout line. Thus, non‐interchangeable CESA classes evolved separately in mosses and seed plants. However, testing of chimeric moss CESA genes for complementation demonstrated that functional class‐specificity is not determined by the CSR. Sequence analysis and computational modeling showed that the CSR is intrinsically disordered and contains predicted molecular recognition features, consistent with a possible role in CESA oligomerization and explaining the evolution of class‐specific sequences without selection for class‐specific function.}, number={6}, journal={JOURNAL OF INTEGRATIVE PLANT BIOLOGY}, publisher={Wiley-Blackwell}, author={Scavuzzo-Duggan, Tess R. and Chaves, Arielle M. and Singh, Abhishek and Sethaphong, Latsavongsakda and Slabaugh, Erin and Yingling, Yaroslava G. and Haigler, Candace H. and Roberts, Alison W.}, year={2018}, month={Jun}, pages={481–497} }
 @article{hill_hill_roberts_haigler_tien_2018, title={Domain swaps of Arabidopsis secondary wall cellulose synthases to elucidate their class specificity}, volume={2}, ISSN={2475-4455}, url={http://dx.doi.org/10.1002/PLD3.61}, DOI={10.1002/PLD3.61}, abstractNote={AbstractCellulose microfibrils are synthesized by membrane‐embedded cellulose synthesis complexes (CSCs), currently modeled as hexamers of cellulose synthase (CESA) trimers. The three paralogous CESAs involved in secondary cell wall (SCW) cellulose biosynthesis in Arabidopsis (CESA4, CESA7, CESA8) are similar, but nonredundant, with all three isoforms required for assembly and function of the CSC. The molecular basis of protein–protein recognition among the isoforms is not well understood. To investigate the locations of the interfaces that are responsible for isoform recognition, we swapped three domains between the Arabidopsis CESAs required for SCW synthesis (CESA4, CESA7, and CESA8): N‐terminus, central domain containing the catalytic core, and C‐terminus. Chimeric genes with all pairwise permutations of the domains were tested for in vivo functionality within knockout mutant backgrounds of cesa4, cesa7, and cesa8. Immunoblotting with isoform‐specific antibodies confirmed the anticipated protein expression in transgenic plants. The percent recovery of stem height and crystalline cellulose content was assayed, as compared to wild type, the mutant background lines, and other controls. Retention of the native central domain was sufficient for CESA8 chimeras to function, with neither its N‐terminal nor C‐terminal domains required. The C‐terminal domain is required for class‐specific function of CESA4 and CESA7, and CESA7 also requires its own N‐terminus. Across all isoforms, the results indicate that the central domain, as well as the N‐ and C‐terminal regions, contributes to class‐specific function variously in Arabidopsis CESA4, CESA7, and CESA8.}, number={7}, journal={Plant Direct}, publisher={Wiley}, author={Hill, Joseph Lee, Jr and Hill, Ashley Nicole and Roberts, Alison W. and Haigler, Candace H. and Tien, Ming}, year={2018}, month={Jul}, pages={e00061} }
 @article{haigler_roberts_2018, title={Structure/function relationships in the rosette cellulose synthesis complex illuminated by an evolutionary perspective}, volume={26}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-018-2157-9}, DOI={10.1007/s10570-018-2157-9}, abstractNote={Cellulose microfibrils are a key component of plant cell walls, which in turn compose most of our renewable biomaterials. Consequently, there is considerable interest in understanding how cellulose microfibrils are made in living cells by the plant cellulose synthesis complex (CSC). This remarkable multi-subunit complex contains cellulose synthase (CESA) proteins, and it is often called a rosette due to its six-lobed shape. Each CSC moves within the plasma membrane as it spins a strong cellulose microfibril in its wake. To accomplish this biological manufacturing process, the CESAs harvest an activated sugar substrate from the cytoplasm for use in the polymerization of glucan chains. An elongating glucan is simultaneously translocated across the plasma membrane by each CESA, where the group of chains emanating from one CSC co-crystallizes into a cellulose microfibril that becomes part of the assembling cell wall. Here we review major advances in understanding CESA and CSC structure/function relationships since 2013, when ground-breaking insights about the structure of cellulose synthases in bacteria and plants were published. We additionally discuss: (a) the relationship of CSC substructure to the size of the fundamental cellulose fibril; (b) an evolutionary perspective on the driving force behind the existence of hetero-oligomeric CSCs that currently appear to dominate in land plants; and (c) how cellulose properties may be regulated by CESA and CSC activity. We also pose major questions that still remain in this rapidly changing and exciting research field.}, number={1}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Haigler, Candace H. and Roberts, Alison W.}, year={2018}, month={Dec}, pages={227–247} }
 @article{haigler_2018, title={Two types of cellulose synthesis complex knit the plant cell wall together}, volume={115}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.1808423115}, DOI={10.1073/pnas.1808423115}, abstractNote={Plant secondary cell walls (SCWs) compose most of Earth’s renewable fibers and biomass (1), and they have irreplaceable roles in the plant lifestyle, ecosystem cycles, carbon sequestration, and human industry. Nonetheless, much remains unknown about how these strong, cellulose-rich polymer networks are synthesized and assembled. Watanabe et al. (2) generate key insights into the dynamic regulation of the cellulose synthase (CESA) enzyme family during the transition between the synthesis of the primary cell wall (PCW), which surrounds all expanding plant cells, and the SCW, which confers specialized functions to some cells. The PCW and SCW become unified despite being successively synthesized and having different matrix polymers and cellulose content. This structural coherency is related to the little-explored “transition period” of cell wall synthesis (3⇓⇓–6), the focus of Watanabe et al.’s research (2). Their results provide clues about how differences in SCW properties of diverse plants may arise and point to the isomer-specific regulation of intracellular membrane protein trafficking, leading to important future research directions.

Based on in silico structural comparison with a bacterial enzyme (7), each CESA synthesizes one β-1,4-glucan chain while simultaneously exporting the polymer into the cell wall space. The individual CESAs are organized within a cellulose synthesis complex (CSC), which has six lobes and an average 21.4-nm hexagonal diameter as measured where the transmembrane helices cross the plasma membrane (8) (Fig. 1). Eighteen CESAs are predicted to exist within one CSC (8), which facilitates the coalescence of multiple glucan chains into a microfibril. Each CSC moves within the plasma membrane as it spins a strong, partially crystalline, cellulose microfibril in its wake (9). The locations of CSCs in the membrane and their direction of movement are affected by, but not entirely dependent on, cortical microtubules (6, 9, 10). For example, cortical … 

[↵][1]1Email: candace_haigler{at}ncsu.edu.

 [1]: #xref-corresp-1-1}, number={27}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Haigler, Candace H.}, year={2018}, month={Jun}, pages={6882–6884} }
 @inbook{haigler_davis_slabaugh_kubicki_2016, title={Biosynthesis and Assembly of Cellulose}, ISBN={9781498726023 9781498726030}, url={http://dx.doi.org/10.1201/b20316-11}, DOI={10.1201/b20316-11}, booktitle={Molecular Cell Biology of the Growth and Differentiation of Plant Cells}, publisher={CRC Press}, author={Haigler, Candace and Davis, Jonathan and Slabaugh, Erin and Kubicki, James}, year={2016}, month={Jun}, pages={120–138} }
 @article{nixon_mansouri_singh_du_davis_lee_slabaugh_vandavasi_o’neill_roberts_et al._2016, title={Comparative Structural and Computational Analysis Supports Eighteen Cellulose Synthases in the Plant Cellulose Synthesis Complex}, volume={6}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/srep28696}, DOI={10.1038/srep28696}, abstractNote={AbstractA six-lobed membrane spanning cellulose synthesis complex (CSC) containing multiple cellulose synthase (CESA) glycosyltransferases mediates cellulose microfibril formation. The number of CESAs in the CSC has been debated for decades in light of changing estimates of the diameter of the smallest microfibril formed from the β-1,4 glucan chains synthesized by one CSC. We obtained more direct evidence through generating improved transmission electron microscopy (TEM) images and image averages of the rosette-type CSC, revealing the frequent triangularity and average cross-sectional area in the plasma membrane of its individual lobes. Trimeric oligomers of two alternative CESA computational models corresponded well with individual lobe geometry. A six-fold assembly of the trimeric computational oligomer had the lowest potential energy per monomer and was consistent with rosette CSC morphology. Negative stain TEM and image averaging showed the triangularity of a recombinant CESA cytosolic domain, consistent with previous modeling of its trimeric nature from small angle scattering (SAXS) data. Six trimeric SAXS models nearly filled the space below an average FF-TEM image of the rosette CSC. In summary, the multifaceted data support a rosette CSC with 18 CESAs that mediates the synthesis of a fundamental microfibril composed of 18 glucan chains.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Nixon, B. Tracy and Mansouri, Katayoun and Singh, Abhishek and Du, Juan and Davis, Jonathan K. and Lee, Jung-Goo and Slabaugh, Erin and Vandavasi, Venu Gopal and O’Neill, Hugh and Roberts, Eric M. and et al.}, year={2016}, month={Jun} }
 @article{stiff_haigler_2016, title={Cotton fiber tips have diverse morphologies and show evidence of apical cell wall synthesis}, volume={6}, ISSN={["2045-2322"]}, DOI={10.1038/srep27883}, abstractNote={AbstractCotton fibers arise through highly anisotropic expansion of a single seed epidermal cell. We obtained evidence that apical cell wall synthesis occurs through examining the tips of young elongating Gossypium hirsutum (Gh) and G. barbadense (Gb) fibers. We characterized two tip types in Gh fiber (hemisphere and tapered), each with distinct apical diameter, central vacuole location, and distribution of cell wall components. The apex of Gh hemisphere tips was enriched in homogalacturonan epitopes, including a relatively high methyl-esterified form associated with cell wall pliability. Other wall components increased behind the apex including cellulose and the α-Fuc-(1,2)-β-Gal epitope predominantly found in xyloglucan. Gb fibers had only one narrow tip type featuring characters found in each Gh tip type. Pulse-labeling of cell wall glucans indicated wall synthesis at the apex of both Gh tip types and in distal zones. Living Gh hemisphere and Gb tips ruptured preferentially at the apex upon treatment with wall degrading enzymes, consistent with newly synthesized wall at the apex. Gh tapered tips ruptured either at the apex or distantly. Overall, the results reveal diverse cotton fiber tip morphologies and support primary wall synthesis occurring at the apex and discrete distal regions of the tip.}, journal={SCIENTIFIC REPORTS}, author={Stiff, Michael R. and Haigler, Candace H.}, year={2016}, month={Jun} }
 @inbook{stiff_tuttle_graham_haigler_2016, place={Cham, Switzerland}, series={Sustainable Development and Biodiversity}, title={Cotton Fiber Biotechnology: Potential Controls and Transgenic Improvement of Elongation and Cell Wall Thickening}, volume={13}, ISBN={9783319445694 9783319445700}, ISSN={2352-474X 2352-4758}, url={http://dx.doi.org/10.1007/978-3-319-44570-0_8}, DOI={10.1007/978-3-319-44570-0_8}, abstractNote={Cotton is grown on five continents as an economically important crop. Its long, fine, seed fibers are one of the most highly used natural fibers, providing a high-quality spinnable fiber to the textile industry. The cotton fiberCotton fiber undergoes a complex, staged developmental program, resulting in a single cell that is 1.8–5 cm long with a thick wall composed of about 95 % cellulose. Biotechnological improvements have either directly or indirectly enhanced the fiber properties that are important for spinning, including length, bundle strength, and maturity. These experiments have generally targeted carbohydrate metabolism, cell wall structure, and hormone signaling. In this chapter, we present a brief review of cotton fiber developmentCotton fiber development with a focus on processes affecting elongation and cell wall thickening. We discuss rigorous criteria for evaluating studies on transgenic cotton fiber and mention the challenges of performing such research in the public sector. We highlight selected genetic engineering experiments that have resulted in improved cotton fiber quality Cotton fiber quality and discuss future prospects for use of biotechnology to improve cotton fiberCotton fiber and its competitiveness with synthetic fibers.}, booktitle={Fiber Plants}, publisher={Springer International Publishing}, author={Stiff, Michael R. and Tuttle, J. Rich and Graham, Benjamin P. and Haigler, Candace H.}, editor={Ramawat, K. and Ahuja, M.Editors}, year={2016}, pages={127–153}, collection={Sustainable Development and Biodiversity} }
 @article{andres_coneva_frank_tuttle_samayoa_han_kaur_zhu_fang_bowman_et al._2017, title={Modifications to a LATE MERISTEM IDENTITY1 gene are responsible for the major leaf shapes of Upland cotton (Gossypium hirsutum L.)}, volume={114}, DOI={10.1101/062612}, abstractNote={AbstractLeaf shape is spectacularly diverse. As the primary source of photo-assimilate in major crops, understanding the evolutionary and environmentally induced changes in leaf morphology are critical to improving agricultural productivity. The role of leaf shape in cotton domestication is unique, as breeders have purposefully selected for entire and lobed leaf morphs resulting from a single locus,okra(L-D1). Theokralocus is not only of agricultural importance in cotton (Gossypium hirsutumL.), but through pioneering chimeric and morphometric studies it has contributed to fundamental knowledge about leaf development. Here we show that the major leaf shapes of cotton at theL-D1locus are controlled by a HD-Zip transcription factor most similar toLate Meristem Identity1 (LMI1)gene. The classicalokraleaf shape gene has133-bp tandem duplication in the promoter, correlated with elevated expression, while an 8-bp deletion in the third exon of the presumed wild-typenormalleaf causes a frame-shifted and truncated coding sequence. Virus-induced gene silencing (VIGS) of thisLMI1-likegene in anokravariety was sufficient to induce normal leaf formation. An intermediate leaf shape allele,sub-okra, lacks both the promoter duplication and the exonic deletion. Our results indicate thatsub-okrais the ancestral leaf shape of tetraploid cotton andnormalis a derived mutant allele that came to predominate and define the leaf shape of cultivated cotton.}, number={1}, journal={Proceedings of the National Academy of Sciences of the United States of America}, author={Andres, R. J. and Coneva, V. and Frank, M. H. and Tuttle, J. R. and Samayoa, L. F. and Han, S. W. and Kaur, B. and Zhu, L. L. and Fang, Hui and Bowman, D. T. and et al.}, year={2017}, pages={E57–66} }
 @article{andres_coneva_frank_tuttle_samayoa_han_kaur_zhu_fang_bowman_et al._2016, title={Modifications to a LATE MERISTEM IDENTITY1 gene are responsible for the major leaf shapes of Upland cotton (Gossypium hirsutum L.)}, volume={114}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/PNAS.1613593114}, DOI={10.1073/PNAS.1613593114}, abstractNote={Significance
          
            Leaves are the primary source of photoassimilate in crop plants. A precise understanding of the genetic architecture underlying leaf morphology is critical to engineering climate-resilient crop varieties. An ideal cotton cultivar would produce a lower canopy of broad,
            normal
            leaves before transitioning to an upper canopy of highly lobed,
            okra
            leaves. Here we show that the major leaf shapes of cotton are controlled by the
            okra
            locus, which encodes an HD-Zip transcription factor
            Gossypium hirsutum
            LATE MERISTEM IDENTITY1-D1b
            (
            GhLMI1-D1b
            ). Using gene silencing, we temporarily induced normal leaf formation in
            okra
            , thus validating the candidate gene and creating the leaf shape ideotype in cotton. This study, identifying a single locus responsible for cotton leaf shape, expands the genetic toolbox for breeders to produce superior cotton varieties.
          }, number={1}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Andres, Ryan J. and Coneva, Viktoriya and Frank, Margaret H. and Tuttle, John R. and Samayoa, Luis Fernando and Han, Sang-Won and Kaur, Baljinder and Zhu, Linglong and Fang, Hui and Bowman, Daryl T. and et al.}, year={2016}, month={Dec}, pages={E57–E66} }
 @article{vandavasi_putnam_zhang_petridis_heller_nixon_haigler_kalluri_coates_langan_et al._2016, title={Structural Studies of Plant CESA Support Eighteen CESAs in the Plant CSC}, volume={110}, ISSN={0006-3495}, url={http://dx.doi.org/10.1016/J.BPJ.2015.11.208}, DOI={10.1016/J.BPJ.2015.11.208}, abstractNote={The cellulose synthesis in plants is carried by a large multi-subunit transmembrane protein complex known as cellulose synthesis complex (CSC). The structural information on plant cellulose synthase (CESA) proteins that constitute CSC has remained challenging over years due to inherent complexities in the CSC leading to speculations and debates on the composition of CSC and the number of cellulose chains in a microfibril. Here, we report our findings on the structural properties of catalytic domain of Arabidopsis thaliana CESA1 (ATCESA1CatD) analyzed using small-angle scattering and computational modeling techniques. Our main findings include low resolution structures of ATCESA1CatD in monomeric and trimeric complex forms that provide the first experimental evidence supporting the self-assembly of CESAs into stable trimeric complexes. This is of immense importance in the context of CSC formation by plant CESAs and addresses a long standing question in plant biology - how many CESAs in the plant cellulose synthesis complex? Further, the scattering data in combination with computational modeling provided insight into the potential arrangement the monomers in the catalytic trimer and the relative arrangement of P-CR and CSR regions that are unique in the plants. Comparison of the size of the trimer complex with the dimensions of CSCs from TEM images provides compelling evidence that each lobe of a CSC contains three CESAs rather than the long-standing model of six CESAs within each lobe of a rosette CSC. To our knowledge, these studies are the first experimental evidence that CESA trimers form the lobes of rosette CSCs providing strong support for the hexamer of trimers model that synthesizes an 18-chain cellulose microfibril as the fundamental product of cellulose synthesis in plants.}, number={3}, journal={Biophysical Journal}, publisher={Elsevier BV}, author={Vandavasi, Venu G. and Putnam, Daniel K. and Zhang, Qiu and Petridis, Loukas and Heller, William T. and Nixon, B. Tracy and Haigler, Candace H. and Kalluri, Udaya and Coates, Leighton and Langan, Paul and et al.}, year={2016}, month={Feb}, pages={27a} }
 @article{vandavasi_putnam_zhang_petridis_heller_nixon_haigler_kalluri_coates_langan_et al._2016, title={A Structural Study of CESA1 Catalytic Domain of Arabidopsis Cellulose Synthesis Complex: Evidence for CESA Trimers}, volume={170}, ISSN={0032-0889 1532-2548}, url={http://dx.doi.org/10.1104/pp.15.01356}, DOI={10.1104/pp.15.01356}, abstractNote={Assembly into stable trimers provides strong evidence for 18 protein subunits to assemble in a cellulose synthesis complex that synthesizes an 18-chain cellulose microfibril. A cellulose synthesis complex with a “rosette” shape is responsible for synthesis of cellulose chains and their assembly into microfibrils within the cell walls of land plants and their charophyte algal progenitors. The number of cellulose synthase proteins in this large multisubunit transmembrane protein complex and the number of cellulose chains in a microfibril have been debated for many years. This work reports a low resolution structure of the catalytic domain of CESA1 from Arabidopsis (Arabidopsis thaliana; AtCESA1CatD) determined by small-angle scattering techniques and provides the first experimental evidence for the self-assembly of CESA into a stable trimer in solution. The catalytic domain was overexpressed in Escherichia coli, and using a two-step procedure, it was possible to isolate monomeric and trimeric forms of AtCESA1CatD. The conformation of monomeric and trimeric AtCESA1CatD proteins were studied using small-angle neutron scattering and small-angle x-ray scattering. A series of AtCESA1CatD trimer computational models were compared with the small-angle x-ray scattering trimer profile to explore the possible arrangement of the monomers in the trimers. Several candidate trimers were identified with monomers oriented such that the newly synthesized cellulose chains project toward the cell membrane. In these models, the class-specific region is found at the periphery of the complex, and the plant-conserved region forms the base of the trimer. This study strongly supports the “hexamer of trimers” model for the rosette cellulose synthesis complex that synthesizes an 18-chain cellulose microfibril as its fundamental product.}, number={1}, journal={Plant Physiology}, publisher={American Society of Plant Biologists (ASPB)}, author={Vandavasi, Venu Gopal and Putnam, Daniel K. and Zhang, Qiu and Petridis, Loukas and Heller, William T. and Nixon, B. Tracy and Haigler, Candace H. and Kalluri, Udaya and Coates, Leighton and Langan, Paul and et al.}, year={2016}, month={Jan}, pages={123–135} }
 @article{lee_kafle_belias_park_glick_haigler_kim_2015, title={Comprehensive analysis of cellulose content, crystallinity, and lateral packing in Gossypium hirsutum and Gossypium barbadense cotton fibers using sum frequency generation, infrared and Raman spectroscopy, and X-ray diffraction}, volume={22}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-014-0535-5}, DOI={10.1007/s10570-014-0535-5}, number={2}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Lee, Christopher M. and Kafle, Kabindra and Belias, David W. and Park, Yong Bum and Glick, Richard E. and Haigler, Candace H. and Kim, Seong H.}, year={2015}, month={Jan}, pages={971–989} }
 @article{tuttle_nah_duke_alexander_guan_song_chen_scheffler_haigler_2015, title={Metabolomic and transcriptomic insights into how cotton fiber transitions to secondary wall synthesis, represses lignification, and prolongs elongation}, volume={16}, ISSN={1471-2164}, url={http://dx.doi.org/10.1186/s12864-015-1708-9}, DOI={10.1186/s12864-015-1708-9}, abstractNote={The morphogenesis of single-celled cotton fiber includes extreme elongation and staged cell wall differentiation. Designing strategies for improving cotton fiber for textiles and other uses relies on uncovering the related regulatory mechanisms. In this research we compared the transcriptomes and metabolomes of two Gossypium genotypes, Gossypium barbadense cv Phytogen 800 and G. hirsutum cv Deltapine 90. When grown in parallel, the two types of fiber developed similarly except for prolonged fiber elongation in the G. barbadense cultivar. The data were collected from isolated fibers between 10 to 28 days post anthesis (DPA) representing: primary wall synthesis to support elongation; transitional cell wall remodeling; and secondary wall cellulose synthesis, which was accompanied by continuing elongation only in G. barbadense fiber. Of 206 identified fiber metabolites, 205 were held in common between the two genotypes. Approximately 38,000 transcripts were expressed in the fiber of each genotype, and these were mapped to the reference set and interpreted by homology to known genes. The developmental changes in the transcriptomes and the metabolomes were compared within and across genotypes with several novel implications. Transitional cell wall remodeling is a distinct stable developmental stage lasting at least four days (18 to 21 DPA). Expression of selected cell wall related transcripts was similar between genotypes, but cellulose synthase gene expression patterns were more complex than expected. Lignification was transcriptionally repressed in both genotypes. Oxidative stress was lower in the fiber of G. barbadense cv Phytogen 800 as compared to G. hirsutum cv Deltapine 90. Correspondingly, the G. barbadense cultivar had enhanced capacity for management of reactive oxygen species during its prolonged elongation period, as indicated by a 138-fold increase in ascorbate concentration at 28 DPA. The parallel data on deep-sequencing transcriptomics and non-targeted metabolomics for two genotypes of single-celled cotton fiber showed that a discrete developmental stage of transitional cell wall remodeling occurs before secondary wall cellulose synthesis begins. The data showed how lignification can be transcriptionally repressed during secondary cell wall synthesis, and they implicated enhanced capacity to manage reactive oxygen species through the ascorbate-glutathione cycle as a positive contributor to fiber length.}, number={1}, journal={BMC Genomics}, publisher={Springer Science and Business Media LLC}, author={Tuttle, John R. and Nah, Gyoungju and Duke, Mary V. and Alexander, Danny C. and Guan, Xueying and Song, Qingxin and Chen, Z. Jeffrey and Scheffler, Brian E. and Haigler, Candace H.}, year={2015}, month={Jun} }
 @article{sethaphong_davis_slabaugh_singh_haigler_yingling_2016, title={Prediction of the structures of the plant-specific regions of vascular plant cellulose synthases and correlated functional analysis}, volume={23}, ISSN={0969-0239 1572-882X}, url={http://dx.doi.org/10.1007/s10570-015-0789-6}, DOI={10.1007/s10570-015-0789-6}, number={1}, journal={Cellulose}, publisher={Springer Science and Business Media LLC}, author={Sethaphong, Latsavongsakda and Davis, Jonathan K. and Slabaugh, Erin and Singh, Abhishek and Haigler, Candace H. and Yingling, Yaroslava G.}, year={2016}, month={Feb}, pages={145–161} }
 @article{slabaugh_scavuzzo-duggan_chaves_wilson_wilson_davis_cosgrove_anderson_roberts_haigler_2015, title={The valine and lysine residues in the conserved FxVTxK motif are important for the function of phylogenetically distant plant cellulose synthases}, volume={26}, ISSN={0959-6658 1460-2423}, url={http://dx.doi.org/10.1093/glycob/cwv118}, DOI={10.1093/glycob/cwv118}, abstractNote={Cellulose synthases (CESAs) synthesize the β-1,4-glucan chains that coalesce to form cellulose microfibrils in plant cell walls. In addition to a large cytosolic (catalytic) domain, CESAs have eight predicted transmembrane helices (TMHs). However, analogous to the structure of BcsA, a bacterial CESA, predicted TMH5 in CESA may instead be an interfacial helix. This would place the conserved FxVTxK motif in the plant cell cytosol where it could function as a substrate-gating loop as occurs in BcsA. To define the functional importance of the CESA region containing FxVTxK, we tested five parallel mutations in Arabidopsis thaliana CESA1 and Physcomitrella patens CESA5 in complementation assays of the relevant cesa mutants. In both organisms, the substitution of the valine or lysine residues in FxVTxK severely affected CESA function. In Arabidopsis roots, both changes were correlated with lower cellulose anisotropy, as revealed by Pontamine Fast Scarlet. Analysis of hypocotyl inner cell wall layers by atomic force microscopy showed that two altered versions of Atcesa1 could rescue cell wall phenotypes observed in the mutant background line. Overall, the data show that the FxVTxK motif is functionally important in two phylogenetically distant plant CESAs. The results show that Physcomitrella provides an efficient model for assessing the effects of engineered CESA mutations affecting primary cell wall synthesis and that diverse testing systems can lead to nuanced insights into CESA structure-function relationships. Although CESA membrane topology needs to be experimentally determined, the results support the possibility that the FxVTxK region functions similarly in CESA and BcsA.}, number={5}, journal={Glycobiology}, publisher={Oxford University Press (OUP)}, author={Slabaugh, Erin and Scavuzzo-Duggan, Tess and Chaves, Arielle and Wilson, Liza and Wilson, Carmen and Davis, Jonathan K and Cosgrove, Daniel J and Anderson, Charles T and Roberts, Alison W and Haigler, Candace H}, year={2015}, month={Dec}, pages={509–519} }
 @inbook{tuttle_haigler_robertson_2015, title={Virus-Induced Gene Silencing of Fiber-Related Genes in Cotton}, volume={1287}, ISBN={9781493924523 9781493924530}, ISSN={1064-3745 1940-6029}, url={http://dx.doi.org/10.1007/978-1-4939-2453-0_16}, DOI={10.1007/978-1-4939-2453-0_16}, abstractNote={Virus-Induced Gene Silencing (VIGS) is a useful method for transient downregulation of gene expression in crop plants. The geminivirus Cotton leaf crumple virus (CLCrV) has been modified to serve as a VIGS vector for persistent gene silencing in cotton. Here the use of Green Fluorescent Protein (GFP) is described as a marker for identifying silenced tissues in reproductive tissues, a procedure that requires the use of transgenic plants. Suggestions are given for isolating and cloning combinations of target and marker sequences so that the total length of inserted foreign DNA is between 500 and 750 bp. Using this strategy, extensive silencing is achieved with only 200–400 bp of sequence homologous to an endogenous gene, reducing the possibility of off-target silencing. Cotyledons can be inoculated using either the gene gun or Agrobacterium and will continue to show silencing throughout fruit and fiber development. CLCrV is not transmitted through seed, and VIGS is limited to genes expressed in the maternally derived seed coat and fiber in the developing seed. This complicates the use of GFP as a marker for VIGS because cotton fibers must be separated from unsilenced tissue in the seed to determine if they are silenced. Nevertheless, fibers from a large number of seeds can be rapidly screened following placement into 96-well plates. Methods for quantifying the extent of silencing using semiquantitative RT-PCR are given.}, booktitle={Methods in Molecular Biology}, publisher={Springer New York}, author={Tuttle, John R. and Haigler, Candace H. and Robertson, Dominique}, year={2015}, pages={219–234} }
 @article{slabaugh_sethaphong_xiao_amick_anderson_haigler_yingling_2014, title={Computational and genetic evidence that different structural conformations of a non-catalytic region affect the function of plant cellulose synthase}, volume={65}, ISSN={1460-2431 0022-0957}, url={http://dx.doi.org/10.1093/jxb/eru383}, DOI={10.1093/jxb/eru383}, abstractNote={Summary Computational modelling of peptide structure, genetic complementation in Arabidopsis thaliana, and confocal microscopy provide evidence that a region between two transmembrane helices may adopt two predominant structural conformations that affect the function of plant cellulose synthase.}, number={22}, journal={Journal of Experimental Botany}, publisher={Oxford University Press (OUP)}, author={Slabaugh, Erin and Sethaphong, Latsavongsakda and Xiao, Chaowen and Amick, Joshua and Anderson, Charles T. and Haigler, Candace H. and Yingling, Yaroslava G.}, year={2014}, month={Sep}, pages={6645–6653} }
 @article{haigler_grimson_gervais_le moigne_höfte_monasse_navard_2014, title={Molecular Modeling and Imaging of Initial Stages of Cellulose Fibril Assembly: Evidence for a Disordered Intermediate Stage}, volume={9}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0093981}, DOI={10.1371/journal.pone.0093981}, abstractNote={The remarkable mechanical strength of cellulose reflects the arrangement of multiple β-1,4-linked glucan chains in a para-crystalline fibril. During plant cellulose biosynthesis, a multimeric cellulose synthesis complex (CSC) moves within the plane of the plasma membrane as many glucan chains are synthesized from the same end and in close proximity. Many questions remain about the mechanism of cellulose fibril assembly, for example must multiple catalytic subunits within one CSC polymerize cellulose at the same rate? How does the cellulose fibril bend to align horizontally with the cell wall? Here we used mathematical modeling to investigate the interactions between glucan chains immediately after extrusion on the plasma membrane surface. Molecular dynamics simulations on groups of six glucans, each originating from a position approximating its extrusion site, revealed initial formation of an uncrystallized aggregate of chains from which a protofibril arose spontaneously through a ratchet mechanism involving hydrogen bonds and van der Waals interactions between glucose monomers. Consistent with the predictions from the model, freeze-fracture transmission electron microscopy using improved methods revealed a hemispherical accumulation of material at points of origination of apparent cellulose fibrils on the external surface of the plasma membrane where rosette-type CSCs were also observed. Together the data support the possibility that a zone of uncrystallized chains on the plasma membrane surface buffers the predicted variable rates of cellulose polymerization from multiple catalytic subunits within the CSC and acts as a flexible hinge allowing the horizontal alignment of the crystalline cellulose fibrils relative to the cell wall.}, number={4}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Haigler, Candace H. and Grimson, Mark J. and Gervais, Julien and Le Moigne, Nicolas and Höfte, Herman and Monasse, Bernard and Navard, Patrick}, editor={Barbosa, Mário A.Editor}, year={2014}, month={Apr}, pages={e93981} }
 @article{slabaugh_davis_haigler_yingling_zimmer_2014, title={Cellulose synthases: new insights from crystallography and modeling}, volume={19}, ISSN={1360-1385}, url={http://dx.doi.org/10.1016/j.tplants.2013.09.009}, DOI={10.1016/j.tplants.2013.09.009}, abstractNote={•A crystal structure and a modeled structure of cellulose synthases are examined. •We explore similarities/differences between bacterial and plant cellulose synthase. •Molecular mechanisms for known cellulose synthase missense mutations are proposed. •We predict specific residues putatively involved in glucan translocation in plants. Detailed information about the structure and biochemical mechanisms of cellulose synthase (CelS) proteins remained elusive until a complex containing the catalytic subunit (BcsA) of CelS from Rhodobacter sphaeroides was crystalized. Additionally, a 3D structure of most of the cytosolic domain of a plant CelS (GhCESA1 from cotton, Gossypium hirsutum) was produced by computational modeling. This predicted structure contributes to our understanding of how plant CelS proteins may be similar and different as compared with BcsA. In this review, we highlight how these structures impact our understanding of the synthesis of cellulose and other extracellular polysaccharides. We show how the structures can be used to generate hypotheses for experiments testing mechanisms of glucan synthesis and translocation in plant CelS. Detailed information about the structure and biochemical mechanisms of cellulose synthase (CelS) proteins remained elusive until a complex containing the catalytic subunit (BcsA) of CelS from Rhodobacter sphaeroides was crystalized. Additionally, a 3D structure of most of the cytosolic domain of a plant CelS (GhCESA1 from cotton, Gossypium hirsutum) was produced by computational modeling. This predicted structure contributes to our understanding of how plant CelS proteins may be similar and different as compared with BcsA. In this review, we highlight how these structures impact our understanding of the synthesis of cellulose and other extracellular polysaccharides. We show how the structures can be used to generate hypotheses for experiments testing mechanisms of glucan synthesis and translocation in plant CelS.}, number={2}, journal={Trends in Plant Science}, publisher={Elsevier BV}, author={Slabaugh, Erin and Davis, Jonathan K. and Haigler, Candace H. and Yingling, Yaroslava G. and Zimmer, Jochen}, year={2014}, month={Feb}, pages={99–106} }
 @article{abidi_cabrales_haigler_2014, title={Changes in the cell wall and cellulose content of developing cotton fibers investigated by FTIR spectroscopy}, volume={100}, ISSN={0144-8617}, url={http://dx.doi.org/10.1016/j.carbpol.2013.01.074}, DOI={10.1016/j.carbpol.2013.01.074}, abstractNote={Fourier transform infrared (FTIR) spectra of cotton fibers harvested at different stages of development were acquired using Universal Attenuated Total Reflectance FTIR (UATR-FTIR). The main goal of the study was to monitor cell wall changes occurring during different phases of cotton fiber development. Two cultivars of Gossypium hirsutum L. were planted in a greenhouse (Texas Marker-1 and TX55). On the day of flowering, individual flowers were tagged and bolls were harvested. From fibers harvested on numerous days between 10 and 56 dpa, the FTIR spectra were acquired using UATR (ZnSe-Diamond crystal) with no special sample preparation. The changes in the FTIR spectra were used to document the timing of the transition between primary and secondary cell wall synthesis. Changes in cellulose during cotton fiber growth and development were identified through changes in numerous vibrations within the spectra. The intensity of the vibration bands at 667 and 897 cm−1 correlated with percentage of cellulose analyzed chemically.}, journal={Carbohydrate Polymers}, publisher={Elsevier BV}, author={Abidi, Noureddine and Cabrales, Luis and Haigler, Candace H.}, year={2014}, month={Jan}, pages={9–16} }
 @article{avci_pattathil_singh_brown_hahn_haigler_2013, title={Cotton Fiber Cell Walls of Gossypium hirsutum and Gossypium barbadense Have Differences Related to Loosely-Bound Xyloglucan}, volume={8}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0056315}, DOI={10.1371/journal.pone.0056315}, abstractNote={Cotton fiber is an important natural textile fiber due to its exceptional length and thickness. These properties arise largely through primary and secondary cell wall synthesis. The cotton fiber of commerce is a cellulosic secondary wall surrounded by a thin cuticulated primary wall, but there were only sparse details available about the polysaccharides in the fiber cell wall of any cotton species. In addition, Gossypium hirsutum (Gh) fiber was known to have an adhesive cotton fiber middle lamella (CFML) that joins adjacent fibers into tissue-like bundles, but it was unknown whether a CFML existed in other commercially important cotton fibers. We compared the cell wall chemistry over the time course of fiber development in Gh and Gossypium barbadense (Gb), the two most important commercial cotton species, when plants were grown in parallel in a highly controlled greenhouse. Under these growing conditions, the rate of early fiber elongation and the time of onset of secondary wall deposition were similar in fibers of the two species, but as expected the Gb fiber had a prolonged elongation period and developed higher quality compared to Gh fiber. The Gb fibers had a CFML, but it was not directly required for fiber elongation because Gb fiber continued to elongate rapidly after CFML hydrolysis. For both species, fiber at seven ages was extracted with four increasingly strong solvents, followed by analysis of cell wall matrix polysaccharide epitopes using antibody-based Glycome Profiling. Together with immunohistochemistry of fiber cross-sections, the data show that the CFML of Gb fiber contained lower levels of xyloglucan compared to Gh fiber. Xyloglucan endo-hydrolase activity was also higher in Gb fiber. In general, the data provide a rich picture of the similarities and differences in the cell wall structure of the two most important commercial cotton species.}, number={2}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Avci, Utku and Pattathil, Sivakumar and Singh, Bir and Brown, Virginia L. and Hahn, Michael G. and Haigler, Candace H.}, editor={Zhang, JinfaEditor}, year={2013}, month={Feb}, pages={e56315} }
 @article{sethaphong_haigler_kubicki_zimmer_bonetta_debolt_yingling_2013, title={Tertiary model of a plant cellulose synthase}, volume={110}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.1301027110}, DOI={10.1073/pnas.1301027110}, abstractNote={
            A 3D atomistic model of a plant cellulose synthase (CESA) has remained elusive despite over forty years of experimental effort. Here, we report a computationally predicted 3D structure of 506 amino acids of cotton CESA within the cytosolic region. Comparison of the predicted plant CESA structure with the solved structure of a bacterial cellulose-synthesizing protein validates the overall fold of the modeled glycosyltransferase (GT) domain. The coaligned plant and bacterial GT domains share a six-stranded β-sheet, five α-helices, and conserved motifs similar to those required for catalysis in other GT-2 glycosyltransferases. Extending beyond the cross-kingdom similarities related to cellulose polymerization, the predicted structure of cotton CESA reveals that plant-specific modules (plant-conserved region and class-specific region) fold into distinct subdomains on the periphery of the catalytic region. Computational results support the importance of the plant-conserved region and/or class-specific region in CESA oligomerization to form the multimeric cellulose–synthesis complexes that are characteristic of plants. Relatively high sequence conservation between plant CESAs allowed mapping of known mutations and two previously undescribed mutations that perturb cellulose synthesis in
            Arabidopsis thaliana
            to their analogous positions in the modeled structure. Most of these mutation sites are near the predicted catalytic region, and the confluence of other mutation sites supports the existence of previously undefined functional nodes within the catalytic core of CESA. Overall, the predicted tertiary structure provides a platform for the biochemical engineering of plant CESAs.
          }, number={18}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Sethaphong, L. and Haigler, C. H. and Kubicki, J. D. and Zimmer, J. and Bonetta, D. and DeBolt, S. and Yingling, Y. G.}, year={2013}, month={Apr}, pages={7512–7517} }
 @article{haigler_betancur_stiff_tuttle_2012, title={Cotton fiber: a powerful single-cell model for cell wall and cellulose research}, volume={3}, ISSN={1664-462X}, url={http://dx.doi.org/10.3389/fpls.2012.00104}, DOI={10.3389/fpls.2012.00104}, abstractNote={Cotton fibers are single-celled extensions of the seed epidermis. They can be isolated in pure form as they undergo staged differentiation including primary cell wall synthesis during elongation and nearly pure cellulose synthesis during secondary wall thickening. This combination of features supports clear interpretation of data about cell walls and cellulose synthesis in the context of high throughput modern experimental technologies. Prior contributions of cotton fiber to building fundamental knowledge about cell walls will be summarized and the dynamic changes in cell wall polymers throughout cotton fiber differentiation will be described. Recent successes in using stable cotton transformation to alter cotton fiber cell wall properties as well as cotton fiber quality will be discussed. Futurec prospects to perform experiments more rapidly through altering cotton fiberwall properties via virus-induced gene silencing will be evaluated.}, journal={Frontiers in Plant Science}, publisher={Frontiers Media SA}, author={Haigler, Candace H. and Betancur, Lissete and Stiff, Michael R. and Tuttle, John R.}, year={2012} }
 @article{tuttle_haigler_robertson_2012, title={Method: low-cost delivery of the cotton leaf crumple virus-induced gene silencing system}, volume={8}, ISSN={1746-4811}, url={http://dx.doi.org/10.1186/1746-4811-8-27}, DOI={10.1186/1746-4811-8-27}, abstractNote={We previously developed a virus-induced gene silencing (VIGS) vector for cotton from the bipartite geminivirusCotton leaf crumple virus (CLCrV). The original CLCrV VIGS vector was designed for biolistic delivery by a gene gun. This prerequisite limited the use of the system to labs with access to biolistic equipment. Here we describe the adaptation of this system for delivery by Agrobacterium (Agrobacterium tumefaciens). We also describe the construction of two low-cost particle inflow guns. The biolistic CLCrV vector was transferred into two Agrobacterium binary plasmids. Agroinoculation of the binary plasmids into cotton resulted in silencing and GFP expression comparable to the biolistic vector. Two homemade low-cost gene guns were used to successfully inoculate cotton (G. hirsutum) and N. benthamiana with either the CLCrV VIGS vector or the Tomato golden mosaic virus (TGMV) VIGS vector respectively. These innovations extend the versatility of CLCrV-based VIGS for analyzing gene function in cotton. The two low-cost gene guns make VIGS experiments affordable for both research and teaching labs by providing a working alternative to expensive commercial gene guns.}, number={1}, journal={Plant Methods}, publisher={Springer Science and Business Media LLC}, author={Tuttle, John and Haigler, Candace H and Robertson, Dominique}, year={2012}, pages={27} }
 @article{roberts_roberts_haigler_2012, title={Moss cell walls: structure and biosynthesis}, volume={3}, ISSN={1664-462X}, url={http://dx.doi.org/10.3389/fpls.2012.00166}, DOI={10.3389/fpls.2012.00166}, abstractNote={The genome sequence of the moss Physcomitrella patens has stimulated new research examining the cell wall polysaccharides of mosses and the glycosyl transferases that synthesize them as a means to understand fundamental processes of cell wall biosynthesis and plant cell wall evolution. The cell walls of mosses and vascular plants are composed of the same classes of polysaccharides, but with differences in side chain composition and structure. Similarly, the genomes of P. patens and angiosperms encode the same families of cell wall glycosyl transferases, yet, in many cases these families have diversified independently in each lineage. Our understanding of land plant evolution could be enhanced by more complete knowledge of the relationships among glycosyl transferase functional diversification, cell wall structural and biochemical specialization, and the roles of cell walls in plant adaptation. As a foundation for these studies, we review the features of P. patens as an experimental system, analyses of cell wall composition in various moss species, recent studies that elucidate the structure and biosynthesis of cell wall polysaccharides in P. patens, and phylogenetic analysis of P. patens genes potentially involved in cell wall biosynthesis.}, journal={Frontiers in Plant Science}, publisher={Frontiers Media SA}, author={Roberts, Alison W. and Roberts, Eric M. and Haigler, Candace H.}, year={2012} }
 @inbook{stiff_haigler_2012, place={Cordova, TN}, series={The Cotton Foundation Reference Book Series}, title={Recent Advances in Cotton Fiber Development}, ISBN={978-0-939809-08-0}, url={(http://www.cotton.org/foundation/fandfcontents.cfm), Cotton Physiology Book Series, The Cotton Foundation, Cordova TN}, booktitle={Flowering and Fruiting in Cotton}, publisher={The Cotton Foundation}, author={Stiff, M.R. and Haigler, C.H.}, editor={Oosterhuis, D.M. and Cothren, J.T.Editors}, year={2012}, pages={163–192}, collection={The Cotton Foundation Reference Book Series} }
 @article{paterson_wendel_gundlach_guo_jenkins_jin_llewellyn_showmaker_shu_udall_et al._2012, title={Repeated polyploidization of Gossypium genomes and the evolution of spinnable cotton fibres}, volume={492}, ISSN={0028-0836 1476-4687}, url={http://dx.doi.org/10.1038/nature11798}, DOI={10.1038/nature11798}, abstractNote={The Gossypium genus is used to investigate emergent consequences of polyploidy in cotton species; comparative genomic analyses reveal a complex evolutionary history including interactions among subgenomes that result in genetic novelty in elite cottons and provide insight into the evolution of spinnable fibres. A phylogenetic and genomic study of plants of the cotton genus Gossypium provides insights into the role of polyploidy in the angiosperm evolution, and specifically, in the emergence of spinnable fibres in domesticated cottons. The authors show that an abrupt five- to sixfold ploidy increase about 60 million years ago, and allopolyploidy reuniting divergent genomes approximately 1–2 million years ago, conferred a roughly 30-fold duplication of ancestral flowering plant genes in the 'elite' cottons G. hirsutum and G. barbadense compared to their presumed progenitor G. raimondii. Polyploidy often confers emergent properties, such as the higher fibre productivity and quality of tetraploid cottons than diploid cottons bred for the same environments1. Here we show that an abrupt five- to sixfold ploidy increase approximately 60 million years (Myr) ago, and allopolyploidy reuniting divergent Gossypium genomes approximately 1–2 Myr ago2, conferred about 30–36-fold duplication of ancestral angiosperm (flowering plant) genes in elite cottons (Gossypium hirsutum and Gossypium barbadense), genetic complexity equalled only by Brassica3 among sequenced angiosperms. Nascent fibre evolution, before allopolyploidy, is elucidated by comparison of spinnable-fibred Gossypium herbaceum A and non-spinnable Gossypium longicalyx F genomes to one another and the outgroup D genome of non-spinnable Gossypium raimondii. The sequence of a G. hirsutum AtDt (in which ‘t’ indicates tetraploid) cultivar reveals many non-reciprocal DNA exchanges between subgenomes that may have contributed to phenotypic innovation and/or other emergent properties such as ecological adaptation by polyploids. Most DNA-level novelty in G. hirsutum recombines alleles from the D-genome progenitor native to its New World habitat and the Old World A-genome progenitor in which spinnable fibre evolved. Coordinated expression changes in proximal groups of functionally distinct genes, including a nuclear mitochondrial DNA block, may account for clusters of cotton-fibre quantitative trait loci affecting diverse traits. Opportunities abound for dissecting emergent properties of other polyploids, particularly angiosperms, by comparison to diploid progenitors and outgroups.}, number={7429}, journal={Nature}, publisher={Springer Science and Business Media LLC}, author={Paterson, Andrew H. and Wendel, Jonathan F. and Gundlach, Heidrun and Guo, Hui and Jenkins, Jerry and Jin, Dianchuan and Llewellyn, Danny and Showmaker, Kurtis C. and Shu, Shengqiang and Udall, Joshua and et al.}, year={2012}, month={Dec}, pages={423–427} }
 @article{joshi_thammannagowda_fujino_gou_avci_haigler_mcdonnell_mansfield_mengesha_carpita_et al._2011, title={Perturbation of Wood Cellulose Synthesis Causes Pleiotropic Effects in Transgenic Aspen}, volume={4}, ISSN={1674-2052}, url={http://dx.doi.org/10.1093/mp/ssq081}, DOI={10.1093/mp/ssq081}, abstractNote={Genetic manipulation of cellulose biosynthesis in trees may provide novel insights into the growth and development of trees. To explore this possibility, the overexpression of an aspen secondary wall-associated cellulose synthase (PtdCesA8) gene was attempted in transgenic aspen (Populus tremuloides L.) and unexpectedly resulted in silencing of the transgene as well as its endogenous counterparts. The main axis of the transgenic aspen plants quickly stopped growing, and weak branches adopted a weeping growth habit. Furthermore, transgenic plants initially developed smaller leaves and a less extensive root system. Secondary xylem (wood) of transgenic aspen plants contained as little as 10% cellulose normalized to dry weight compared to 41% cellulose typically found in normal aspen wood. This massive reduction in cellulose was accompanied by proportional increases in lignin (35%) and non-cellulosic polysaccharides (55%) compared to the 22% lignin and 36% non-cellulosic polysaccharides in control plants. The transgenic stems produced typical collapsed or 'irregular' xylem vessels that had altered secondary wall morphology and contained greatly reduced amounts of crystalline cellulose. These results demonstrate the fundamental role of secondary wall cellulose within the secondary xylem in maintaining the strength and structural integrity required to establish the vertical growth habit in trees.}, number={2}, journal={Molecular Plant}, publisher={Elsevier BV}, author={Joshi, Chandrashekhar P. and Thammannagowda, Shivegowda and Fujino, Takeshi and Gou, Ji-Qing and Avci, Utku and Haigler, Candace H. and McDonnell, Lisa M. and Mansfield, Shawn D. and Mengesha, Bemnet and Carpita, Nicholas C. and et al.}, year={2011}, month={Mar}, pages={331–345} }
 @article{santa-maria_yencho_haigler_thompson_kelly_sosinski_2011, title={Starch Self-Processing in Transgenic Sweet Potato Roots Expressing a Hyperthermophilic alpha-Amylase}, volume={27}, ISSN={["1520-6033"]}, url={http://europepmc.org/abstract/med/21365786}, DOI={10.1002/btpr.573}, abstractNote={AbstractSweet potato is a major crop in the southeastern United States, which requires few inputs and grows well on marginal land. It accumulates large quantities of starch in the storage roots and has been shown to give comparable or superior ethanol yields to corn per cultivated acre in the southeast. Starch conversion to fermentable sugars (i.e., for ethanol production) is carried out at high temperatures and requires the action of thermostable and thermoactive amylolytic enzymes. These enzymes are added to the starch mixture impacting overall process economics. To address this shortcoming, the gene encoding a hyperthermophilic α‐amylase from Thermotoga maritima was cloned and expressed in transgenic sweet potato, generated by Agrobacterium tumefaciens‐mediated transformation, to create a plant with the ability to self‐process starch. No significant enzyme activity could be detected below 40°C, but starch in the transgenic sweet potato storage roots was readily hydrolyzed at 80°C. The transgene did not affect normal storage root formation. The results presented here demonstrate that engineering plants with hyperthermophilic glycoside hydrolases can facilitate cost effective starch conversion to fermentable sugars. Furthermore, the use of sweet potato as an alternative near‐term energy crop should be considered. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011}, number={2}, journal={BIOTECHNOLOGY PROGRESS}, author={Santa-Maria, Monica C. and Yencho, Craig G. and Haigler, Candace H. and Thompson, William F. and Kelly, Robert M. and Sosinski, Bryon}, year={2011}, pages={351–359} }
 @article{taliercio_haigler_2011, place={Memphis, TN}, title={The effect of calcium on early fiber elongation in cotton ovule culture}, volume={15}, ISSN={1524-3303}, url={http://journal.cotton.org/journal/2011-15/2/154.cfm}, journal={Journal of Cotton Science}, publisher={The Cotton Foundation}, author={Taliercio, E. and Haigler, C.H.}, year={2011}, pages={154–161} }
 @article{livingston_tuong_gadi_haigler_gelman_cullen_2010, title={3D volumes constructed from pixel-based images by digitally clearing plant and animal tissue}, volume={240}, ISSN={0022-2720}, url={http://dx.doi.org/10.1111/j.1365-2818.2010.03393.x}, DOI={10.1111/j.1365-2818.2010.03393.x}, abstractNote={SummaryConstruction of three‐dimensional volumes from a series of two‐dimensional images has been restricted by the limited capacity to decrease the opacity of tissue. The use of commercial software that allows colour‐keying and manipulation of two‐dimensional images in true three‐dimensional space allowed us to construct three‐dimensional volumes from pixel‐based images of stained plant and animal tissue without generating vector information. We present three‐dimensional volumes of (1) the crown of an oat plant showing internal responses to a freezing treatment, (2) a sample of a hepatocellular carcinoma from a woodchuck liver that had been heat‐treated with computer‐guided radiofrequency ablation to induce necrosis in the central portion of the tumour, and (3) several features of a sample of mouse lung. The technique is well suited to images from large sections (greater than 1 mm) generated from paraffin‐embedded tissues. It is widely applicable, having potential to recover three‐dimensional information at virtually any resolution inherent in images generated by light microscopy, computer tomography, magnetic resonance imaging or electron microscopy.}, number={2}, journal={Journal of Microscopy}, publisher={Wiley}, author={Livingston, D.P. and Tuong, T.D. and Gadi, S.R.V. and Haigler, C.H. and Gelman, R.S. and Cullen, J.M.}, year={2010}, month={Jun}, pages={122–129} }
 @article{idris_tuttle_robertson_haigler_brown_2010, title={Differential Cotton leaf crumple virus-VIGS-mediated gene silencing and viral genome localization in different Gossypium hirsutum genetic backgrounds}, volume={75}, ISSN={0885-5765}, url={http://dx.doi.org/10.1016/j.pmpp.2010.07.002}, DOI={10.1016/j.pmpp.2010.07.002}, abstractNote={A Cotton leaf crumple virus (CLCrV)-based gene silencing vector containing a fragment of the Gossypium hirsutum Magnesium chelatase subunit I was used to establish endogenous gene silencing in cotton of varied genetic backgrounds. Biolistic inoculation resulted in systemic and persistent photo-bleaching of the leaves and bolls of the seven cultivars tested, however, the intensity of silencing was variable. CLCrV-VIGS-mediated expression of green fluorescent protein was used to monitor the in planta distribution of the vector, indicating successful phloem invasion in all cultivars tested. Acala SJ-1, one of the cotton cultivars, was identified as a particularly optimal candidate for CLCrV-VIGS-based cotton reverse-genetics.}, number={1-2}, journal={Physiological and Molecular Plant Pathology}, publisher={Elsevier BV}, author={Idris, Ali M. and Tuttle, J.R. and Robertson, D. and Haigler, C.H. and Brown, J.K.}, year={2010}, month={Dec}, pages={13–22} }
 @article{rapp_haigler_flagel_hovav_udall_wendel_2010, title={Gene expression in developing fibres of Upland cotton (Gossypium hirsutum L.) was massively altered by domestication}, volume={8}, ISSN={1741-7007}, url={http://dx.doi.org/10.1186/1741-7007-8-139}, DOI={10.1186/1741-7007-8-139}, abstractNote={Abstract
          
            Background
            Understanding the evolutionary genetics of modern crop phenotypes has a dual relevance to evolutionary biology and crop improvement. Modern upland cotton (Gossypium hirsutum L.) was developed following thousands of years of artificial selection from a wild form, G. hirsutum var. yucatanense, which bears a shorter, sparser, layer of single-celled, ovular trichomes ('fibre'). In order to gain an insight into the nature of the developmental genetic transformations that accompanied domestication and crop improvement, we studied the transcriptomes of cotton fibres from wild and domesticated accessions over a developmental time course.
          
          
            Results
            Fibre cells were harvested between 2 and 25 days post-anthesis and encompassed the primary and secondary wall synthesis stages. Using amplified messenger RNA and a custom microarray platform designed to interrogate expression for 40,430 genes, we determined global patterns of expression during fibre development. The fibre transcriptome of domesticated cotton is far more dynamic than that of wild cotton, with over twice as many genes being differentially expressed during development (12,626 versus 5273). Remarkably, a total of 9465 genes were diagnosed as differentially expressed between wild and domesticated fibres when summed across five key developmental time points. Human selection during the initial domestication and subsequent crop improvement has resulted in a biased upregulation of components of the transcriptional network that are important for agronomically advanced fibre, especially in the early stages of development. About 15% of the differentially expressed genes in wild versus domesticated cotton fibre have no homology to the genes in databases.
          
          
            Conclusions
            We show that artificial selection during crop domestication can radically alter the transcriptional developmental network of even a single-celled structure, affecting nearly a quarter of the genes in the genome. Gene expression during fibre development within accessions and expression alteration arising from evolutionary change appears to be 'modular' - complex genic networks have been simultaneously and similarly transformed, in a coordinated fashion, as a consequence of human-mediated selection. These results highlight the complex alteration of the global gene expression machinery that resulted from human selection for a longer, stronger and finer fibre, as well as other aspects of fibre physiology that were not consciously selected. We illustrate how the data can be mined for genes that were unwittingly targeted by aboriginal and/or modern domesticators during crop improvement and/or which potentially control the improved qualities of domesticated cotton fibre.
            See Commentary: http://www.biomedcentral.com/1741-7007/8/137
            
          }, number={1}, journal={BMC Biology}, publisher={Springer Science and Business Media LLC}, author={Rapp, Ryan A and Haigler, Candace H and Flagel, Lex and Hovav, Ran H and Udall, Joshua A and Wendel, Jonathan F}, year={2010}, pages={139} }
 @article{betancur_singh_rapp_wendel_marks_roberts_haigler_2010, title={Phylogenetically Distinct Cellulose Synthase Genes Support Secondary Wall Thickening in Arabidopsis Shoot Trichomes and Cotton Fiber}, volume={52}, ISSN={1672-9072 1744-7909}, url={http://dx.doi.org/10.1111/j.1744-7909.2010.00934.x}, DOI={10.1111/j.1744-7909.2010.00934.x}, abstractNote={Abstract Through exploring potential analogies between cotton seed trichomes (or cotton fiber) and arabidopsis shoot trichomes we discovered that CesAs from either the primary or secondary wall phylogenetic clades can support secondary wall thickening. CesA genes that typically support primary wall synthesis, AtCesA1,2,3,5, and 6, underpin expansion and secondary wall thickening of arabidopsis shoot trichomes. In contrast, apparent orthologs of CesA genes that support secondary wall synthesis in arabidopsis xylem, AtCesA4,7, and 8, are up‐regulated for cotton fiber secondary wall deposition. These conclusions arose from: (a) analyzing the expression of CesA genes in arabidopsis shoot trichomes; (b) observing birefringent secondary walls in arabidopsis shoot trichomes with mutations in AtCesA4, 7, or 8; (c) assaying up‐regulated genes during different stages of cotton fiber development; and (d) comparing genes that were co‐expressed with primary or secondary wall CesAs in arabidopsis with genes up‐regulated in arabidopsis trichomes, arabidopsis secondary xylem, or cotton fiber during primary or secondary wall deposition. Cumulatively, the data show that: (a) the xylem of arabidopsis provides the best model for secondary wall cellulose synthesis in cotton fiber; and (b) CesA genes within a “cell wall toolbox” are used in diverse ways for the construction of particular specialized cell walls. }, number={2}, journal={Journal of Integrative Plant Biology}, publisher={Wiley}, author={Betancur, Lissete and Singh, Bir and Rapp, Ryan A. and Wendel, Jonathan F. and Marks, M. David and Roberts, Alison W. and Haigler, Candace H.}, year={2010}, month={Feb}, pages={205–220} }
 @article{paterson_rong_gingle_chee_dennis_llewellyn_dure_haigler_myers_peterson_et al._2010, title={Sequencing and Utilization of the Gossypium Genomes}, volume={3}, ISSN={1935-9756 1935-9764}, url={http://dx.doi.org/10.1007/S12042-010-9051-4}, DOI={10.1007/S12042-010-9051-4}, abstractNote={Revealing the genetic underpinnings of cotton productivity will require understanding both the prehistoric evolution of spinnable fibers, and the results of independent domestication processes in both the Old and New Worlds. Progress toward a reference sequence for the smallest Gossypium genome is a logical stepping-stone toward revealing diversity in the remaining seven genomes (A, B, C, E, F, G, K) that permitted Gossypium species to adapt to a wide range of ecosystems in warmer arid regions of the world, and toward identifying the emergent properties that account for the superior productivity and quality of tetraploid cottons. The greatest challenge facing the cotton community is not genome sequencing per se but the conversion of sequence to knowledge.}, number={2}, journal={Tropical Plant Biology}, publisher={Springer Science and Business Media LLC}, author={Paterson, Andrew H. and Rong, Jun-kang and Gingle, Alan R. and Chee, Peng W. and Dennis, Elizabeth S. and Llewellyn, Danny and Dure, Leon S., III and Haigler, Candace and Myers, Gerald O. and Peterson, Daniel G. and et al.}, year={2010}, month={Apr}, pages={71–74} }
 @article{singh_avci_eichler inwood_grimson_landgraf_mohnen_sørensen_wilkerson_willats_haigler_2009, title={A Specialized Outer Layer of the Primary Cell Wall Joins Elongating Cotton Fibers into Tissue-Like Bundles}, volume={150}, ISSN={0032-0889 1532-2548}, url={http://dx.doi.org/10.1104/pp.109.135459}, DOI={10.1104/pp.109.135459}, abstractNote={Abstract
               Cotton (Gossypium hirsutum) provides the world's dominant renewable textile fiber, and cotton fiber is valued as a research model because of its extensive elongation and secondary wall thickening. Previously, it was assumed that fibers elongated as individual cells. In contrast, observation by cryo-field emission-scanning electron microscopy of cotton fibers developing in situ within the boll demonstrated that fibers elongate within tissue-like bundles. These bundles were entrained by twisting fiber tips and consolidated by adhesion of a cotton fiber middle lamella (CFML). The fiber bundles consolidated via the CFML ultimately formed a packet of fiber around each seed, which helps explain how thousands of cotton fibers achieve their great length within a confined space. The cell wall nature of the CFML was characterized using transmission electron microscopy, including polymer epitope labeling. Toward the end of elongation, up-regulation occurred in gene expression and enzyme activities related to cell wall hydrolysis, and targeted breakdown of the CFML restored fiber individuality. At the same time, losses occurred in certain cell wall polymer epitopes (as revealed by comprehensive microarray polymer profiling) and sugars within noncellulosic matrix components (as revealed by gas chromatography-mass spectrometry analysis of derivatized neutral and acidic glycosyl residues). Broadly, these data show that adhesion modulated by an outer layer of the primary wall can coordinate the extensive growth of a large group of cells and illustrate dynamic changes in primary wall structure and composition occurring during the differentiation of one cell type that spends only part of its life as a tissue.}, number={2}, journal={Plant Physiology}, publisher={American Society of Plant Biologists (ASPB)}, author={Singh, Bir and Avci, Utku and Eichler Inwood, Sarah E. and Grimson, Mark J. and Landgraf, Jeff and Mohnen, Debra and Sørensen, Iben and Wilkerson, Curtis G. and Willats, William G.T. and Haigler, Candace H.}, year={2009}, month={Apr}, pages={684–699} }
 @article{singh_cheek_haigler_2009, title={A synthetic auxin (NAA) suppresses secondary wall cellulose synthesis and enhances elongation in cultured cotton fiber}, volume={28}, ISSN={0721-7714 1432-203X}, url={http://dx.doi.org/10.1007/s00299-009-0714-2}, DOI={10.1007/s00299-009-0714-2}, abstractNote={Use of a synthetic auxin (naphthalene-1-acetic acid, NAA) to start (Gossypium hirsutum) ovule/fiber cultures hindered fiber secondary wall cellulose synthesis compared with natural auxin (indole-3-acetic acid, IAA). In contrast, NAA promoted fiber elongation and ovule weight gain, which resulted in larger ovule/fiber units. To reach these conclusions, fiber and ovule growth parameters were measured and cell wall characteristics were examined microscopically. The differences in fiber from NAA and IAA culture were underpinned by changes in the expression patterns of marker genes for three fiber developmental stages (elongation, the transition stage, and secondary wall deposition), and these gene expression patterns were also analyzed quantitatively in plant-grown fiber. The results demonstrate that secondary wall cellulose synthesis: (1) is under strong transcriptional control that is influenced by auxin; and (2) must be specifically characterized in the cotton ovule/fiber culture system given the many protocol variables employed in different laboratories.}, number={7}, journal={Plant Cell Reports}, publisher={Springer Science and Business Media LLC}, author={Singh, Bir and Cheek, Hannah D. and Haigler, Candace H.}, year={2009}, month={May}, pages={1023–1032} }
 @inbook{haigler_roberts_2009, title={Biogenesis of Cellulose Nanofibrils by a Biological Nanomachine}, ISBN={9781444307474 9781405167864}, url={http://dx.doi.org/10.1002/9781444307474.ch2}, DOI={10.1002/9781444307474.ch2}, abstractNote={This chapter contains sections titled: Introduction Background CesA Protein is a Major Component of the Plant CSC The Functional Operation of the CSC Phylogenetic Analysis Conclusion References}, booktitle={The Nanoscience and Technology of Renewable Biomaterials}, publisher={John Wiley & Sons, Ltd}, author={Haigler, Candace H. and Roberts, Alison W.}, year={2009}, month={Sep}, pages={43–59} }
 @inbook{haigler_singh_wang_zhang_2009, title={Genomics of cotton fiber secondary wall deposition and cellulose biogenesis}, ISBN={9780387708096}, DOI={10.1007/978-0-387-70810-2_16}, abstractNote={The deposition of > 90% cellulose in the cotton fiber secondary wall makes this unique cell powerful for understanding cellulose biogenesis, a process with great importance in nature and industry. This chapter provides an overview of cellulose biogenesis, summarizes how cotton fiber has previously facilitated unique insights in this field, and explains how cellulose is important in terms of cotton fiber physical properties. The nature of the cotton fiber secondary wall transcriptome is discussed, including comparisons to primary-wall-stage fiber and the Arabidopsis proteome. Microarray data, including validation by quantitative reverse transcription PCR, are described to show that transcriptomes for secondary wall deposition in cotton fiber and xylem are similar. The functional context of selected genes that are up-regulated for secondary wall deposition is discussed.}, booktitle={Genetics and genomics of cotton}, publisher={New York: Springer Science & Business Media}, author={Haigler, Candace H. and Singh, B. and Wang, G.-R. and Zhang, D.}, year={2009}, pages={385–417} }
 @inbook{haigler_2010, title={Physiological and Anatomical Factors Determining Fiber Structure and Utility}, ISBN={9789048131945 9789048131952}, url={http://dx.doi.org/10.1007/978-90-481-3195-2_4}, DOI={10.1007/978-90-481-3195-2_4}, booktitle={Physiology of Cotton}, publisher={Springer Netherlands}, author={Haigler, C.H.}, year={2010}, pages={33–47} }
 @article{santa-maria_chou_yencho_haigler_thompson_kelly_sosinski_2009, title={Plant cell calcium-rich environment enhances thermostability of recombinantly produced α-amylase from the hyperthermophilic bacterium Thermotoga maritime}, volume={104}, ISSN={0006-3592 1097-0290}, url={http://dx.doi.org/10.1002/bit.22468}, DOI={10.1002/bit.22468}, abstractNote={AbstractIn the industrial processing of starch for sugar syrup and ethanol production, a liquefaction step is involved where starch is initially solubilized at high temperature and partially hydrolyzed with a thermostable and thermoactive α‐amylase. Most amylases require calcium as a cofactor for their activity and stability, therefore calcium, along with the thermostable enzyme, are typically added to the starch mixture during enzymatic liquefaction, thereby increasing process costs. An attractive alternative would be to produce the enzyme directly in the tissue to be treated. In a proof of concept study, tobacco cell cultures were used as model system to test in planta production of a hyperthermophilic α‐amylase from Thermotoga maritima. While comparable biochemical properties to recombinant production in Escherichia coli were observed, thermostability of the plant‐produced α‐amylase benefited significantly from high intrinsic calcium levels in the tobacco cells. The plant‐made enzyme retained 85% of its initial activity after 3 h incubation at 100°C, whereas the E. coli‐produced enzyme was completely inactivated after 30 min under the same conditions. The addition of Ca2+ or plant cell extracts from tobacco and sweetpotato to the E. coli‐produced enzyme resulted in a similar stabilization, demonstrating the importance of a calcium‐rich environment for thermostability, as well as the advantage of producing this enzyme directly in plant cells where calcium is readily available. Biotechnol. Bioeng. 2009; 104: 947–956. © 2009 Wiley Periodicals, Inc.}, number={5}, journal={Biotechnology and Bioengineering}, publisher={Wiley}, author={Santa-Maria, Monica C. and Chou, Chung-Jung and Yencho, G. Craig and Haigler, Candace H. and Thompson, William F. and Kelly, Robert M. and Sosinski, Bryon}, year={2009}, month={Dec}, pages={947–956} }
 @article{livingston_tuong_haigler_avci_tallury_2009, title={Rapid Microwave Processing of Winter Cereals for Histology Allows Identification of Separate Zones of Freezing Injury in the Crown}, volume={49}, ISSN={0011-183X}, url={http://dx.doi.org/10.2135/cropsci2009.02.0077}, DOI={10.2135/cropsci2009.02.0077}, abstractNote={ABSTRACTIn histological studies, microwave processing of tissue considerably shortens the time required to prepare samples for observation under light and electron microscopy. However, plant tissues from different species and different regions of the plant respond differently to microwave processing, making it impossible to use a single protocol for all plant tissue. The crown of winter cereals such as rye (Secale cereale L.), wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and oats (Avena sativa L.) is the below‐ground portion of the stem that overwinters. It is composed of numerous types of cells with an organizational pattern that is similar to other grasses. When we used microwave protocols that were developed for other plant tissues, winter cereal crown tissue shattered and crumbled when sectioned. This study reports a procedure developed to process winter cereal crowns for histological observations. Using this microwave protocol, samples were prepared in 1 d as compared to 2 wk using traditional protocols. This enabled many more samples to be processed and allowed us to identify four overlapping zones of response to freezing within the crown. Results of varying time, temperature, and microwave wattage during fixing, dehydrating, and embedding in paraffin are described. High quality sections from the crowns of oat, barley, wheat, and rye indicate that this procedure is valid for all winter cereals. Since crown tissue is similar across all grass species, we predict that the protocol will be useful for other grasses as well.}, number={5}, journal={Crop Science}, publisher={Wiley}, author={Livingston, D. P., III and Tuong, T. D. and Haigler, C. H. and Avci, U. and Tallury, S. P.}, year={2009}, month={Sep}, pages={1837–1842} }
 @article{marks_betancur_gilding_chen_bauer_wenger_dixon_haigler_2008, title={A new method for isolating large quantities of Arabidopsis trichomes for transcriptome, cell wall and other types of analyses}, volume={56}, ISSN={["0960-7412"]}, DOI={10.1111/j.1365-313X.2008.03611.x}, abstractNote={SummaryA new procedure has been developed for the isolation of wild‐type and mutant Arabidopsis trichomes. The isolated trichomes maintained enzymatic activity and were used for DNA, protein, and RNA isolation. The RNA was used to generate probes suitable for Affymetrix analysis. The validity of the Affymetrix results was confirmed by quantitative PCR analysis on a subset of genes that are preferentially expressed in trichomes or leaves. Sufficient quantities of trichomes were isolated to probe the biochemical nature of trichome cell walls. These analyses provide evidence for the presence of lignin in Arabidopsis trichome cell walls. The monosaccharide analysis and positive staining with ruthenium red indicates that the walls also contain a large portion of pectin. The 2.23‐fold ratio of pectin‐related sugars compared with potential cellulosic glucose suggests that the polysaccharides of the trichome cell walls are more like those of typical primary walls even though the wall becomes quite thick. Overall, these analyses open the door to using the Arabidopsis trichome cell wall as an excellent model to probe various questions concerning plant cell wall biosynthesis.}, number={3}, journal={PLANT JOURNAL}, author={Marks, M. David and Betancur, Lissete and Gilding, Edward and Chen, Fang and Bauer, Stefan and Wenger, Jonathan P. and Dixon, Richard A. and Haigler, Candace H.}, year={2008}, month={Nov}, pages={483–492} }
 @article{avci_petzold_ismail_beers_haigler_2008, title={Cysteine proteases XCP1 and XCP2 aid micro-autolysis within the intact central vacuole during xylogenesis in Arabidopsis roots}, volume={56}, ISSN={["1365-313X"]}, DOI={10.1111/j.1365-313X.2008.03592.x}, abstractNote={SummaryEstablishing the mechanisms regulating the autolysis of xylem tracheary elements (TEs) is important for understanding this programmed cell death process. These data demonstrate that two paralogous Arabidopsis thaliana proteases, XYLEM CYSTEINE PROTEASE1 (XCP1) and XCP2, participated in micro‐autolysis within the intact central vacuole before mega‐autolysis was initiated by tonoplast implosion. The data acquisition was aided by the predictable pattern of seedling root xylogenesis, the availability of single and double total knock‐out T‐DNA lines, anti‐sera that recognized XCP1 and XCP2, and the microwave‐assisted processing of whole seedlings prior to immunolabeling and observation in the transmission electron microscope. During secondary wall thickening, XCP1 and XCP2 (in wild type), XCP1 (in xcp2 seedlings) or XCP2 (in xcp1 seedlings) were imported into the TE central vacuole. Both XCP1 and XCP2 heavily labeled dense aggregates of material within the vacuole. However, because of XCP1 deficiency in xcp1 and xcp1 xcp2 TEs, non‐degraded cellular remnants first accumulated in the vacuole and then persisted in the TE lumen (longer than in the wild type) after the final mega‐autolysis was otherwise complete. This delayed TE clearing phenotype in xcp1 was rescued by complementation with wild‐type XCP1. Although TEs in the xcp2 single knock‐out cleared comparably with wild type, the non‐degraded remnants in xcp1 xcp2 TEs were more densely packed than in xcp1 TEs. Therefore, XCP2 has a minor but distinct role in micro‐autolysis. After tonoplast implosion, XCP1 and XCP2 remained associated with disintegrating cellular material as mega‐autolysis, aided by additional lytic enzymes, destroyed the bulk of the cellular contents.}, number={2}, journal={PLANT JOURNAL}, author={Avci, Utku and Petzold, H. Earl and Ismail, Ihab O. and Beers, Eric P. and Haigler, Candace H.}, year={2008}, month={Oct}, pages={303–315} }
 @article{tuttle_idris_brown_haigler_robertson_2008, title={Geminivirus-Mediated Gene Silencing from Cotton Leaf Crumple Virus Is Enhanced by Low Temperature in Cotton}, volume={148}, ISSN={0032-0889 1532-2548}, url={http://dx.doi.org/10.1104/pp.108.123869}, DOI={10.1104/pp.108.123869}, abstractNote={AbstractA silencing vector for cotton (Gossypium hirsutum) was developed from the geminivirus Cotton leaf crumple virus (CLCrV). The CLCrV coat protein gene was replaced by up to 500 bp of DNA homologous to one of two endogenous genes, the magnesium chelatase subunit I gene (ChlI) or the phytoene desaturase gene (PDS). Cotyledons of cotton cultivar ‘Deltapine 5415’ bombarded with the modified viral vectors manifested chlorosis due to silencing of either ChlI or PDS in approximately 70% of inoculated plants after 2 to 3 weeks. Use of the green fluorescence protein gene showed that replication of viral DNA was restricted to vascular tissue and that the viral vector could transmit to leaves, roots, and the ovule integument from which fibers originate. Temperature had profound effects on vector DNA accumulation and the spread of endogenous gene silencing. Consistent with reports that silencing against viruses increases at higher temperatures, plants grown at a 30°C/26°C day/night cycle had a greater than 10-fold reduction in viral DNA accumulation compared to plants grown at 22°C/18°C. However, endogenous gene silencing decreased at 30°C/26°C. There was an approximately 7 d delay in the onset of gene silencing at 22°C/18°C, but silencing was extensive and persisted throughout the life of the plant. The extent of silencing in new growth could be increased or decreased by changing temperature regimes at various times following the onset of silencing. Our experiments establish the use of the CLCrV silencing vector to study gene function in cotton and show that temperature can have a major impact on the extent of geminivirus-induced gene silencing.}, number={1}, journal={Plant Physiology}, publisher={American Society of Plant Biologists (ASPB)}, author={Tuttle, John R. and Idris, A.M. and Brown, Judith K. and Haigler, Candace H. and Robertson, Dominique}, year={2008}, month={Jul}, pages={41–50} }
 @inproceedings{singh_avci_grimson_inwood_landgraf_mohnen_sorensen_wilkerson_willats_haigler_2007, place={Washington, USA}, title={New controls of cotton fiber development and quality illuminated through integration of genomic, cell biological, and biochemical analyses}, booktitle={Proceedings of the World Cotton Research Conference-4}, publisher={International Cotton Advisory Committee (ICAC)}, author={Singh, B. and Avci, U. and Grimson, M.J. and Inwood, S. E. E. and Landgraf, J. and Mohnen, D. and Sorensen, I. and Wilkerson, C. and Willats, W. G. T. and Haigler, C.H.}, year={2007} }
 @inbook{haigler_2007, title={Substrate supply for cellulose synthesis and its stress sensitivity in the cotton fiber}, ISBN={1402053320}, DOI={10.1007/978-1-4020-5380-1_9}, booktitle={Cellulose: Molecular and structural biology}, publisher={New York: Springer}, author={Haigler, Candace H.}, editor={R. M. Brown and Saxena, I.Editors}, year={2007}, pages={145–166} }
 @article{chen_scheffler_dennis_triplett_zhang_guo_chen_stelly_rabinowicz_town_et al._2007, title={Toward Sequencing Cotton (Gossypium) Genomes: Figure 1.}, volume={145}, ISSN={0032-0889 1532-2548}, url={http://dx.doi.org/10.1104/pp.107.107672}, DOI={10.1104/pp.107.107672}, abstractNote={Despite rapidly decreasing costs and innovative technologies, sequencing of angiosperm genomes is not yet undertaken lightly. Generating larger amounts of sequence data more quickly does not address the difficulties of sequencing and assembling complex genomes de novo. The cotton ( Gossypium spp.)}, number={4}, journal={Plant Physiology}, publisher={American Society of Plant Biologists (ASPB)}, author={Chen, Z. Jeffrey and Scheffler, Brian E. and Dennis, Elizabeth and Triplett, Barbara A. and Zhang, Tianzhen and Guo, Wangzhen and Chen, Xiaoya and Stelly, David M. and Rabinowicz, Pablo D. and Town, Christopher D. and et al.}, year={2007}, month={Dec}, pages={1303–1310} }
 @article{haigler_singh_zhang_hwang_wu_cai_hozain_kang_kiedaisch_strauss_et al._2007, title={Transgenic cotton over-producing spinach sucrose phosphate synthase showed enhanced leaf sucrose synthesis and improved fiber quality under controlled environmental conditions}, volume={63}, ISSN={["1573-5028"]}, DOI={10.1007/s11103-006-9127-6}, abstractNote={Prior data indicated that enhanced availability of sucrose, a major product of photosynthesis in source leaves and the carbon source for secondary wall cellulose synthesis in fiber sinks, might improve fiber quality under abiotic stress conditions. To test this hypothesis, a family of transgenic cotton plants (Gossypium hirsutum cv. Coker 312 elite) was produced that over-expressed spinach sucrose-phosphate synthase (SPS) because of its role in regulation of sucrose synthesis in photosynthetic and heterotrophic tissues. A family of 12 independent transgenic lines was characterized in terms of foreign gene insertion, expression of spinach SPS, production of spinach SPS protein, and development of enhanced extractable V (max) SPS activity in leaf and fiber. Lines with the highest V (max) SPS activity were further characterized in terms of carbon partitioning and fiber quality compared to wild-type and transgenic null controls. Leaves of transgenic SPS over-expressing lines showed higher sucrose:starch ratio and partitioning of (14)C to sucrose in preference to starch. In two growth chamber experiments with cool nights, ambient CO(2) concentration, and limited light below the canopy, the transgenic line with the highest SPS activity in leaf and fiber had higher fiber micronaire and maturity ratio associated with greater thickness of the cellulosic secondary wall.}, number={6}, journal={PLANT MOLECULAR BIOLOGY}, author={Haigler, Candace H. and Singh, Bir and Zhang, Deshui and Hwang, Sangjoon and Wu, Chunfa and Cai, Wendy X. and Hozain, Mohamed and Kang, Wonhee and Kiedaisch, Brett and Strauss, Richard E. and et al.}, year={2007}, month={Apr}, pages={815–832} }
 @article{zhao_avci_grant_haigler_beers_2008, title={XND1, a member of the NAC domain family in Arabidopsis thaliana, negatively regulates lignocellulose synthesis and programmed cell death in xylem}, volume={53}, ISSN={["0960-7412"]}, DOI={10.1111/j.1365-313X.2007.03350.x}, abstractNote={SummaryMembers of the large Arabidopsis NAC domain transcription factor family are regulators of meristem development, organ elongation and separation, and deposition of patterned secondary cell walls. XYLEM NAC DOMAIN 1 (XND1) is highly expressed in xylem. Changes observed for XND1 knockout plants compared with wild‐type Arabidopsis thaliana included a reduction in both plant height and tracheary element length and an increase in metaxylem relative to protoxylem in roots of plants treated with the proteasome inhibitor MG132. Overexpression of XND1 resulted in extreme dwarfism associated with the absence of xylem vessels and little or no expression of tracheary element marker genes. In contrast, phloem marker‐gene expression was not altered and phloem‐type cells still formed. Transmission electron microscopy showed that parenchyma‐like cells in the incipient xylem zone in hypocotyls of XND1 overexpressors lacked secondary wall thickenings and retained their cytoplasmic content. Considered together, these findings suggest that XND1 affects tracheary element growth through regulation of secondary wall synthesis and programmed cell death.}, number={3}, journal={PLANT JOURNAL}, author={Zhao, Chengsong and Avci, Utku and Grant, Emily H. and Haigler, Candace H. and Beers, Eric P.}, year={2008}, month={Feb}, pages={425–436} }
 @article{udall_swanson_haller_rapp_sparks_hatfield_yu_wu_dowd_arpat_et al._2006, title={A global assembly of cotton ESTs}, volume={16}, ISSN={["1549-5469"]}, DOI={10.1101/gr.4602906}, abstractNote={Approximately 185,000GossypiumEST sequences comprising >94,800,000 nucleotides were amassed from 30 cDNA libraries constructed from a variety of tissues and organs under a range of conditions, including drought stress and pathogen challenges. These libraries were derived from allopolyploid cotton (Gossypium hirsutum; ATand DTgenomes) as well as its two diploid progenitors,Gossypium arboreum(A genome) andGossypium raimondii(D genome). ESTs were assembled using the Program for Assembling and Viewing ESTs (PAVE), resulting in 22,030 contigs and 29,077 singletons (51,107 unigenes). Further comparisons among the singletons and contigs led to recognition of 33,665 exemplar sequences that represent a nonredundant set of putativeGossypiumgenes containing partial or full-length coding regions and usually one or two UTRs. The assembly, along with their UniProt BLASTX hits, GO annotation, and Pfam analysis results, are freely accessible as a public resource for cotton genomics. Because ESTs from diploid and allotetraploidGossypiumwere combined in a single assembly, we were in many cases able to bioinformatically distinguish duplicated genes in allotetraploid cotton and assign them to either the A or D genome. The assembly and associated information provide a framework for future investigation of cotton functional and evolutionary genomics.}, number={3}, journal={GENOME RESEARCH}, author={Udall, JA and Swanson, JM and Haller, K and Rapp, RA and Sparks, ME and Hatfield, J and Yu, YS and Wu, YR and Dowd, C and Arpat, AB and et al.}, year={2006}, month={Mar}, pages={441–450} }
 @inproceedings{hudson_haigler_davis_2006, title={Analysis of cell wall synthesis in feeding cells formed by root-knot nematodes}, booktitle={Biology of plant-microbe interactions - Proceedings of the 12th International Congress on Molecular Plant-Microbe Interactions, Mérida, Yucatán, México}, author={Hudson, L.C. and Haigler, C. and Davis, E.L.}, year={2006}, pages={281–285} }
 @misc{haigler_zhang_wu_zhang_2006, title={Chitinase encoding DNA molecules from cotton expressed preferentially in secondary walled cells during secondary wall deposition and a corresponding promoter}, volume={7,098,324}, number={2006 Aug. 29}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Haigler, C. H. and Zhang, H. and Wu, C. and Zhang, D.}, year={2006} }
 @inbook{haigler_2006, title={Establishing the cellular and biophysical context of cellulose synthesis}, booktitle={The science and lore of the plant cell wall: Biosynthesis, structure and function}, publisher={Boca Raton, FL: BrownWalker Press}, author={Haigler, C. H.}, year={2006}, pages={97–105} }
 @misc{haigler_holaday_2006, title={Transgenic fiber producing plants with increased expression of sucrose phosphate synthase}, volume={7,091,400}, number={2006 Aug. 15}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Haigler, C. H. and Holaday, A. S.}, year={2006} }
 @misc{haigler_zhang_wilkerson_2005, title={Biotechnological improvement of cotton fibre maturity}, volume={124}, ISSN={["1399-3054"]}, DOI={10.1111/j.1399-3054.2005.00480.x}, abstractNote={This mini‐review focuses on the prospects and tools for controlling cotton fibre secondary wall thickness. Cotton fibre secondary walls are composed of almost 100% cellulose, and are responsible for fibre maturity and a large component of fibre yield. Improved fibre yield and maturity would result from the ability to control secondary wall cellulose deposition quantitatively, including making the process less sensitive to environmental stress. Both genetic engineering and marker‐assisted breeding are possible avenues for effecting such improvements, but first key genes that participate in the regulation and control of secondary wall cellulose biogenesis must be identified. Recent advances towards understanding and manipulating cotton fibre secondary wall deposition that are discussed here include: (i) experimental approaches to identify metabolic participants in cellulose biogenesis; (ii) isolation and characterization of promoters to drive foreign gene expression preferentially during secondary wall deposition; and (iii) a novel set of cDNA sequences representing genes that are differentially expressed during cotton fibre secondary wall deposition compared with primary wall deposition.}, number={3}, journal={PHYSIOLOGIA PLANTARUM}, author={Haigler, CH and Zhang, DH and Wilkerson, CG}, year={2005}, month={Jul}, pages={285–294} }
 @article{singh_haley_nightengale_kang_haigler_holaday_2005, title={Long-term night chilling of cotton (Gossypium hirsutum) does not result in reduced CO2 assimilation}, volume={32}, ISSN={["1445-4416"]}, DOI={10.1071/FP05018}, abstractNote={

The aim of this study was to characterise the response of CO2 assimilation (A) of cotton (Gossypium hirsutum L.) to short- and long-term exposures to night chilling. We hypothesised that short-term exposures to night chilling would induce reductions in gs and, therefore, A during the following days, while growth of cotton plants for several weeks in cool night conditions would cause elevated leaf carbohydrate content, leading to the down-regulation of the capacity for A. Transferring warm-grown seedlings of wild type cotton, transgenic cotton with elevated sucrose-phosphate synthase activity (SPS+) that might produce and export more sucrose from the leaf, and a segregating null to cool nights (9°C minimum) for 1 or 2 d caused a small reduction in A (12%) and gs (21–50%) measured at 28°C. Internal CO2 did not change, suggesting some biochemical restriction of A along with a gs restriction. After 30 d, new leaves that developed in cool nights exhibited acclimation of A and partial acclimation of gs. Despite the elevated leaf carbohydrate content when plants were grown to maturity with night chilling, no reduction in A, gs, carboxylation capacity, electron transport capacity, or triose-phosphate utilisation capacity occurred. Instead, growth in cool nights tended to retard the diminishing of photosynthetic parameters and gs for aging stem and subtending leaves. However, elevated SPS activity did not affect any photosynthetic parameters. Therefore, when cotton that is well fertilised with nitrogen is grown with continuous night chilling, photosynthesis should not be negatively affected. However, an occasional exposure to cool nights could result in a small reduction in A and gs for leaves that have developed in warm night conditions.
}, number={7}, journal={FUNCTIONAL PLANT BIOLOGY}, author={Singh, B and Haley, L and Nightengale, J and Kang, WH and Haigler, CH and Holaday, AS}, year={2005}, pages={655–666} }
 @book{atalla_beecher_caron_catchmark_deng_glasser_gray_haigler_jones_joyce_et al._2005, title={Nanotechnology for the forest products industry: Vision and technology roadmap}, ISBN={1595100873}, DOI={10.2172/1218797}, abstractNote={A roadmap for Nanotechnology in the Forest Products Industries has been developed under the umbrella of the Agenda 2020 program overseen by the CTO committee. It is expected that the use of new analytical techniques and methodologies will allow us to understand the complex nature of wood based materials and allow the dramatically enhanced use of the major strategic asset the US has in renewable, recyclable resources based on its well managed Forests.}, publisher={Madison, WI: USDA Forest Products Laboratory}, author={Atalla, R. and Beecher, J. and Caron, B. and Catchmark, J. and Deng, Y. and Glasser, W. and Gray, D. and Haigler, Candace H. and Jones, P. and Joyce, M. and et al.}, year={2005} }
 @article{martin_haigler_2004, title={Cool temperature hinders flux from glucose to sucrose during cellulose synthesis in secondary wall stage cotton fibers}, volume={11}, ISSN={["1572-882X"]}, DOI={10.1023/B:CELL.0000046420.10403.15}, number={3-4}, journal={CELLULOSE}, author={Martin, LK and Haigler, CH}, year={2004}, pages={339–349} }
 @article{zhang_hrmova_wan_wu_balzen_cai_wang_densmore_fincher_zhang_et al._2004, title={Members of a new group of chitinase-like genes are expressed preferentially in cotton cells with secondary walls}, volume={54}, ISSN={["1573-5028"]}, DOI={10.1023/B:PLAN.0000036369.55253.dd}, abstractNote={Two homologous cotton (Gossypium hirsutum L.) genes, GhCTL1 and GhCTL2, encode members of a new group of chitinase-like proteins (called the GhCTL group) that includes other proteins from two cotton species, Arabidopsis, rice, and pea. Members of the GhCTL group are assigned to family GH19 glycoside hydrolases along with numerous authentic chitinases (http://afmb.cnrs-mrs.fr/CAZY/index.html), but the proteins have novel consensus sequences in two regions that are essential for chitinase activity and that were previously thought to be conserved. Maximum parsimony phylogenetic analyses, as well as Neighbor-Joining distance analyses, of numerous chitinases confirmed that the GhCTL group is distinct. A molecular model of GhCTL2 (based on the three-dimensional structure of a barley chitinase) had changes in the catalytic site that are likely to abolish catalytic activity while retaining potential to bind chitin oligosaccharides. RNA blot analysis showed that members of the GhCTL group had preferential expression during secondary wall deposition in cotton lint fiber. Cotton transformed with a fusion of the GhCTL2 promoter to the beta -d-glucuronidase gene showed preferential reporter gene activity in numerous cells during secondary wall deposition. Together with evidence from other researchers that mutants in an Arabidopsis gene within the GhCTL group are cellulose-deficient with phenotypes indicative of altered primary cell walls, these data suggest that members of the GhCTL group of chitinase-like proteins are essential for cellulose synthesis in primary and secondary cell walls. However, the mechanism by which they act is more likely to involve binding of chitin oligosaccharides than catalysis.}, number={3}, journal={PLANT MOLECULAR BIOLOGY}, author={Zhang, DS and Hrmova, M and Wan, CH and Wu, CF and Balzen, J and Cai, W and Wang, J and Densmore, LD and Fincher, GB and Zhang, H and et al.}, year={2004}, month={Feb}, pages={353–372} }
 @article{roberts_frost_roberts_haigler_2004, title={Roles of microtubules and cellulose microfibril assembly in the localization of secondary-cell-wall deposition in developing tracheary elements}, volume={224}, ISSN={["0033-183X"]}, DOI={10.1007/s00709-004-0064-4}, abstractNote={The roles of cellulose microfibrils and cortical microtubules in establishing and maintaining the pattern of secondary-cell-wall deposition in tracheary elements were investigated with direct dyes to inhibit cellulose microfibril assembly and amiprophosmethyl to inhibit microtubule polymerization. When direct dyes were added to xylogenic cultures of Zinnia elegans L. mesophyll cells just before the onset of differentiation, the secondary cell wall was initially secreted as bands composed of discrete masses of stained material, consistent with immobilized sites of cellulose synthesis. The masses coalesced, forming truncated, sinuous or smeared thickenings, as secondary cell wall deposition continued. The absence of ordered cellulose microfibrils was confirmed by polarization microscopy and a lack of fluorescence dichroism as determined by laser scanning microscopy. Indirect immunofluorescence showed that cortical microtubules initially subtended the masses of dye-altered secondary cell wall material but soon became disorganized and disappeared. Although most of the secondary cell wall was deposited in the absence of subtending cortical microtubules in dye-treated cells, secretion remained confined to discrete regions of the plasma membrane. Examination of non-dye-treated cultures following application of microtubule inhibitors during various stages of secondary-cell-wall deposition revealed that the pattern became fixed at an early stage such that deposition remained localized in the absence of cortical microtubules. These observations indicate that cortical microtubules are required to establish, but not to maintain, patterned secondary-cell-wall deposition. Furthermore, cellulose microfibrils play a role in maintaining microtubule arrays and the integrity of the secondary-cell-wall bands during deposition.}, number={3-4}, journal={PROTOPLASMA}, author={Roberts, AW and Frost, AO and Roberts, EM and Haigler, CH}, year={2004}, month={Dec}, pages={217–229} }
 @article{kiedaisch_blanton_haigler_2003, title={Characterization of a novel cellulose synthesis inhibitor}, volume={217}, ISSN={["0032-0935"]}, DOI={10.1007/s00425-003-1071-y}, abstractNote={The physiological effects of an experimental herbicide and cellulose synthesis inhibitor, N2-(1-ethyl-3-phenylpropyl)-6-(1-fluoro-1-methylethyl)-1,3,5-triazine-2,4-diamine, called AE F150944, are described. In the aminotriazine molecular class, AE F150944 is structurally distinct from other known cellulose synthesis inhibitors. It specifically inhibits crystalline cellulose synthesis in plants without affecting other processes that were tested. The effects of AE F150944 on dicotyledonous plants were tested on cultured mesophyll cells of Zinnia elegans L. cv. Envy, which can be selectively induced to expand via primary wall synthesis or to differentiate into tracheary elements via secondary wall synthesis. The IC50 values during primary and secondary wall synthesis in Z. elegans were 3.91 x 10(-8) M and 3.67 x 10(-9) M, respectively. The IC50 in suspension cultures of the monocot Sorghum halapense (L.) Pers., which were dividing and synthesizing primary walls, was 1.67 x 10(-10) M. At maximally inhibitory concentrations, 18-33% residual crystalline cellulose synthesis activity remained, with the most residual activity observed during primary wall synthesis in Z. elegans. Addition to Z. elegans cells of two other cellulose synthesis inhibitors, 1 microM 2,6-dichlorobenzonitrile and isoxaben, along with AE F150944 did not eliminate the residual cellulose synthesis, indicating little synergy between the three inhibitors. In differentiating tracheary elements, AE F150944 inhibited the deposition of detectable cellulose into patterned secondary wall thickenings, which was correlated with delocalization of lignin as described previously for 2, 6-dichlorobenzonitrile. Freeze-fracture electron microscopy showed that the plasma membrane below the patterned thickenings of AE F150944-treated tracheary elements was depleted of cellulose-synthase-containing rosettes, which appeared to be inserted intact into the plasma membrane followed by their rapid disaggregation. AE F150944 also inhibited cellulose-dependent growth in the rosette-containing alga, Spirogyra pratensis, but it did not inhibit cellulose synthesis in Acetobacter xylinum or Dictyostelium discoideum, both of which synthesize cellulose via linear terminal complexes. Therefore, AE F150944 may inhibit crystalline cellulose synthesis by destabilizing plasma membrane rosettes.}, number={6}, journal={PLANTA}, author={Kiedaisch, BM and Blanton, RL and Haigler, CH}, year={2003}, month={Oct}, pages={922–930} }
 @article{salnikov_grimson_seagull_haigler_2003, title={Localization of sucrose synthase and callose in freeze-substituted secondary-wall-stage cotton fibers}, volume={221}, ISSN={["0033-183X"]}, DOI={10.1007/s00709-002-0079-7}, abstractNote={Methods for cryogenic fixation, freeze substitution, and embedding were developed to preserve the cellular structure and protein localization of secondary-wall-stage cotton (Gossypium hirsutum L.) fibers accurately for the first time. Perturbation by specimen handling was minimized by freezing fibers still attached to a seed fragment within 2 min after removal of seeds from a boll still attached to the plant. These methods revealed native ultrastructure, including numerous active Golgi bodies, multivesicular bodies, and proplastids. Immunolocalization in the context of accurate structure was accomplished after freeze substitution in acetone only. Quantitation of immunolabeling identified sucrose synthase both near the cortical microtubules and plasma membrane and in a proximal exoplasmic zone about 0.2 microm thick. Immunolabeling also showed that callose (beta-1,3-glucan) was codistributed with sucrose synthase within this exoplasmic zone. Similar results were obtained from cultured cotton fibers. The distribution of sucrose synthase is consistent with its having a dual role in cellulose and callose synthesis in secondary-wall-stage cotton fibers.}, number={3-4}, journal={PROTOPLASMA}, author={Salnikov, VV and Grimson, MJ and Seagull, RW and Haigler, CH}, year={2003}, pages={175–184} }
 @inproceedings{haigler_2003, title={Progress and emerging questions in understanding cellulose biogenesis}, booktitle={Proceedings, Vol. 1: 12th International Symposium on Wood and Pulping Chemistry}, publisher={Madison: University of Wisconsin}, author={Haigler, C. H.}, year={2003}, pages={9–16} }
 @article{delmer_haigler_2002, title={The regulation of metabolic flux to cellulose, a major sink for carbon in plants}, volume={4}, ISSN={["1096-7176"]}, DOI={10.1006/mben.2001.0206}, abstractNote={Cellulose is an important component of the cell walls of higher plants and the world's most abundant organic compound. As a major sink for carbon on earth, it is of interest to examine possible means by which the quality or quantity of cellulose deposited in various plant parts might be manipulated by metabolic engineering techniques. This review outlines basic knowledge about the genes and proteins that are involved in cellulose biosynthesis and presents a model that summarizes our current thinking on the overall cellulose biosynthesis pathway. Strategies that might be used for altering the flux of carbon into this pathway are discussed.}, number={1}, journal={METABOLIC ENGINEERING}, author={Delmer, DP and Haigler, CH}, year={2002}, month={Jan}, pages={22–28} }
 @misc{haigler_holaday_2002, title={Transgenic cotton plants with altered fiber characteristics transformed with a sucrose phosphate synthase nucleic acid}, volume={6,472,588}, number={2002 Oct. 29}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Haigler, C. H. and Holaday, A. S.}, year={2002} }
 @misc{haigler_ivanova-datcheva_hogan_salnikov_hwang_martin_delmer_2001, title={Carbon partitioning to cellulose synthesis}, volume={47}, ISSN={["1573-5028"]}, DOI={10.1023/A:1010615027986}, number={1-2}, journal={PLANT MOLECULAR BIOLOGY}, author={Haigler, CH and Ivanova-Datcheva, M and Hogan, PS and Salnikov, VV and Hwang, S and Martin, K and Delmer, DP}, year={2001}, pages={29–51} }
 @article{haigler_babb_hwang_salnikov_2001, title={Regulation of cellulose biosynthesis in developing xylem}, volume={18}, ISBN={["0-444-50958-5"]}, ISSN={["0921-0423"]}, DOI={10.1016/s0921-0423(01)80050-2}, abstractNote={The advantages of using isolated mesophyll cells of Zinnia elegans as a model to study the regulation of cellulose synthesis will be discussed. These cells can be induced by different mechanisms to expand greatly via primary wall synthesis or to differentiate into tracheary elements with patterned secondary walls. Therefore, mechanisms of cellulose synthesis during primary and secondary wall deposition can be studied separately in cultured cells. Recent work discussed includes the activity and role of sucrose synthase and sucrose phosphate synthase during secondary wall cellulose synthesis and the diversity of cellulose synthase genes expressed during tracheary element differentiation. Evidence obtained during primary and secondary wall synthesis in cultured Zinnia cells is compared and contrasted. Data presented include immunolocalization of sucrose synthase and actin in cryogenically fixed cells, biochemical analysis of sucrose phosphate synthase activity during the time-course of tracheary element differentiation, and cloning and analysis of multiple cellulose synthase genes expressed differentially during secondary wall deposition in tracheary elements in culture. Differentiating cotton fibers and etiolated bean hypocotyls will be discussed as related systems. A composite cellular and metabolic model for cellulose synthesis will be presented.}, journal={MOLECULAR BREEDING OF WOODY PLANTS, PROCEEDINGS}, publisher={Amsterdam: Elsevier Science}, author={Haigler, CH and Babb, VM and Hwang, S and Salnikov, VV}, year={2001}, pages={1–9} }
 @article{babb_haigler_2001, title={Sucrose phosphate synthase activity rises in correlation with high-rate cellulose synthesis in three heterotrophic systems}, volume={127}, DOI={10.1104/pp.010424}, abstractNote={Abstract
               Based on work with cotton fibers, a particulate form of sucrose (Suc) synthase was proposed to support secondary wall cellulose synthesis by degrading Suc to fructose and UDP-glucose. The model proposed that UDP-glucose was then channeled to cellulose synthase in the plasma membrane, and it implies that Suc availability in cellulose sink cells would affect the rate of cellulose synthesis. Therefore, if cellulose sink cells could synthesize Suc and/or had the capacity to recycle the fructose released by Suc synthase back to Suc, cellulose synthesis might be supported. The capacity of cellulose sink cells to synthesize Suc was tested by analyzing the Suc phosphate synthase (SPS) activity of three heterotrophic systems with cellulose-rich secondary walls. SPS is a primary regulator of the Suc synthesis rate in leaves and some Suc-storing, heterotrophic organs, but its activity has not been previously correlated with cellulose synthesis. Two systems analyzed, cultured mesophyll cells of Zinnia elegans L. var. Envy and etiolated hypocotyls of kidney beans (Phaseolus vulgaris), contained differentiating tracheary elements. Cotton (Gossypium hirsutum L. cv Acala SJ-1) fibers were also analyzed during primary and secondary wall synthesis. SPS activity rose in all three systems during periods of maximum cellulose deposition within secondary walls. The Z. elegans culture system was manipulated to establish a tight linkage between the timing of tracheary element differentiation and rising SPS activity and to show that SPS activity did not depend on the availability of starch for degradation. The significance of these findings in regard to directing metabolic flux toward cellulose will be discussed.}, journal={Plant Physiology}, author={Babb, V. M. and Haigler, Candace H.}, year={2001}, pages={1234–1242} }
 @article{salnikov_grimson_delmar_haigler_2001, title={Sucrose synthase localizes to cellulose synthesis sites in tracheary elements}, volume={57}, ISSN={["0031-9422"]}, DOI={10.1016/S0031-9422(01)00045-0}, abstractNote={The synthesis of crystalline cellulose microfibrils in plants is a highly coordinated process that occurs at the interface of the cortex, plasma membrane, and cell wall. There is evidence that cellulose biogenesis is facilitated by the interaction of several proteins, but the details are just beginning to be understood. In particular, sucrose synthase, microtubules, and actin have been proposed to possibly associate with cellulose synthases (microfibril terminal complexes) in the plasma membrane. Differentiating tracheary elements of Zinnia elegans L. were used as a model system to determine the localization of sucrose synthase and actin in relation to the plasma membrane and its underlying microtubules during the deposition of patterned, cellulose-rich secondary walls. Cortical actin occurs with similar density both between and under secondary wall thickenings. In contrast, sucrose synthase is highly enriched near the plasma membrane and the microtubules under the secondary wall thickenings. Both actin and sucrose synthase lie closer to the plasma membrane than the microtubules. These results show that the preferential localization of sucrose synthase at sites of high-rate cellulose synthesis can be generalized beyond cotton fibers, and they establish a spatial context for further work on a multi-protein complex that may facilitate secondary wall cellulose synthesis.}, number={6}, journal={PHYTOCHEMISTRY}, author={Salnikov, VV and Grimson, MJ and Delmar, DP and Haigler, CH}, year={2001}, month={Jul}, pages={823–833} }
 @inbook{haigler_cai_gannaway_grimson_hequet_holaday_huang_jaradat_jividen_krieg_et al._2000, title={Optimizing secondary wall synthesis in cotton fibers}, booktitle={Genetic control of cotton fiber and seed quality}, publisher={Cary, NC: Cotton Incorporated}, author={Haigler, C. H. and Cai, W. X. and Gannaway, J. G. and Grimson, M. J. and Hequet, E. F. and Holaday, A. S. and Huang, J.-Y. and Jaradat, T. T. and Jividen, G. J. and Krieg, D. R. and et al.}, year={2000}, pages={147–165} }
 @article{roberts_donovan_haigler_1997, title={A secreted factor induces cell expansion and formation of metaxylem-like tracheary elements in xylogenic suspension cultures of Zinnia}, volume={115}, ISSN={["0032-0889"]}, DOI={10.1104/pp.115.2.683}, abstractNote={Abstract
               Conditioned medium from mesophyll cell-suspension cultures of Zinnia elegans L. has striking effects on cell expansion and tracheary element differentiation when applied to cultures of freshly isolated mesophyll cells. These effects include (a) induction of early cell expansion, (b) delay in differentiation by 48 h or more, (c) reduction in the synchrony of differentiation, and (d) early formation of very large, metaxylem-like tracheary elements. Like reduced osmotic potential and buffering at pH 5.5, conditioned medium appears to have its primary effect on cell expansion. Partial characterization of the expansion-inducing factor indicates that it is heat stable, of low molecular mass, and is resistant to protease. It also binds reversibly to concanavalin A but is not adsorbed by charcoal. We suggest that the secreted factor may be an oligosaccharide involved in the coordination of cell expansion and differentiation and the regulation of the protoxylem-like to metaxylem-like transition in xylogenic suspension cultures.}, number={2}, journal={PLANT PHYSIOLOGY}, author={Roberts, AW and Donovan, SG and Haigler, CH}, year={1997}, month={Oct}, pages={683–692} }
 @inbook{blanton_haigler_1996, title={Cellulose biosynthesis}, ISBN={1859962009}, booktitle={Membranes: Specialized functions in plants}, publisher={Oxford, UK: BIOS Scientific Publishers}, author={Blanton, R. L. and Haigler, C. H.}, editor={M. Smallwood, J. P. Knox and Bowles, D. J.Editors}, year={1996}, pages={57–75} }
 @article{grimson_haigler_blanton_1996, title={Cellulose microfibrils, cell motility, and plasma membrane organization change in parallel during culmination in Dictyostelium discoideum}, volume={109}, journal={Journal of Cell Science}, author={Grimson, M. J. and Haigler, C. H. and Blanton, R. L.}, year={1996}, pages={3079–3087} }
 @article{taylor_haigler_kilburn_blanton_1996, title={Detection of cellulose with improved specificity using laser-based instruments}, volume={71}, ISSN={["1473-7760"]}, DOI={10.3109/10520299609117163}, abstractNote={Specific detection of cellulose has not been possible using laser based instruments such as laser scanning confocal microscopes (LSCM) and fluorescently activated cell sorters (FACS). Common cellulose dyes are nonspecific and/or nonexcitable with common lasers. Furthermore, many lasers emit wavelengths that overlap with autofluorescence from chlorophyll and other plant molecules. We demonstrate that a cellulase and an isolated bacterial cellulose binding domain (CBD) conjugated to fluorescent dyes can be used for laser detection of cellulose with improved specificity. Cell walls of differentiating tracheary elements and spores of Dictyostelium discoideum were tested in this study. For double labeling, autofluorescence interfering with the rhodamine signal was eliminated by collecting each excitation channel separately followed by computer recombination or by using a narrow band pass barrier filter allowing simultaneous channel collection. Using these methods, cellulose and microtubules tagged with a monoclonal antibody to alpha-tubulin were effectively colocalized in chlorophyll-containing tracheary elements using a LSCM. Also, Dictyostelium discoideum spores labeled or unlabeled with CBD-FITC were separated into two populations by FACS indicating that this tag should be useful in future mutagenesis experiments. Therefore, the presence or absence of cellulose can now be analyzed using common lasers.}, number={5}, journal={BIOTECHNIC & HISTOCHEMISTRY}, author={Taylor, JG and Haigler, CH and Kilburn, DG and Blanton, RL}, year={1996}, month={Sep}, pages={215–223} }
 @article{haigler_blanton_1996, title={New hope for old dreams: Evidence that plant cellulose synthase genes have finally been identified}, volume={93}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.93.22.12082}, abstractNote={It is common in the cellulose literature to read that cellulose is the most abundant macromolecule on earth. Authors perhaps hoped that the abundance of the polymer would compensate for the lack of progress in understanding the biochemistry and molecular biology of its synthesis in higher plants! Despite substantial effort, cellulose biogenesis has remained for decades one of the most enigmatic aspects of plant biochemistry, with only low activity observable in vitro, no synthase purified to homogeneity, and no relevant genes identified. Many scientists who tried to make progress eventually quit to concentrate on more productive and publishable research. However, the subject is of such critical importance to plant biology and global productivity that a few research groups worldwide persevered. Cellulose is important because it is an almost ubiquitous component of plant cell walls. The high molecular weight chains of the (1 -> 4)-f-D-glucan homopolymer form crystalline microfibrils of high tensile strength (Fig. la), and, in growing walls, the microfibril orientation constrains the direction of plant cell expansion. Therefore, cellulose synthesis is a fundamental determinant of plant growth rate (without it, plants cannot grow substantially) and morphogenesis (because plant cells do not migrate during development, direction of cell expansion determines plant form). Furthermore, cellulose is a substantial component of the biomass produced and decomposed in the biosphere because it is highly abundant in thick secondary walls of plant cells that conduct water and provide support, finally forming wood in trees. Cellulose also composes the secondary cell walls of cotton fibers, our most important natural fiber. Finally, cellulose biogenesis likely reflects many novel regulatory processes, since the cytoplasmic precursor UDP-glc is converted at the plasma membrane into insoluble extracytoplasmic microfibrils, which are often laid down in precise patterns. For all these reasons, it is essential to understand how the synthesis of cellulose is regulated. One of the research groups that persevered in the study of cellulose biogenesis was that of Deborah P. Delmer, who, along with her associate Yasushi Kawagoe, is a coauthor on the paper in this issue of the Proceedings identifying the first strong candidates for higher plant cellulose synthase genes (1). Other authors on the paper, Julie R. Pear, William E. Schreckengost, and David M. Stalker are from Calgene, a biotechnology company interested in the control and modification of cotton fiber development. Their approach was not biochemical, relying instead on random sequencing of plant cDNAs combined with insightful sequence analysis. This finding is noteworthy because it provides the first likely direct route to unraveling the cellular and molecular details of plant cellulose biogenesis.}, number={22}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Haigler, CH and Blanton, RL}, year={1996}, month={Oct}, pages={12082–12085} }
 @article{amor_haigler_johnson_wainscott_delmer_1995, title={A MEMBRANE-ASSOCIATED FORM OF SUCROSE SYNTHASE AND ITS POTENTIAL ROLE IN SYNTHESIS OF CELLULOSE AND CALLOSE IN PLANTS}, volume={92}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.92.20.9353}, abstractNote={Sucrose synthase (SuSy; EC 2.4.1.13; sucrose + UDP reversible UDPglucose + fructose) has always been studied as a cytoplasmic enzyme in plant cells where it serves to degrade sucrose and provide carbon for respiration and synthesis of cell wall polysaccharides and starch. We report here that at least half of the total SuSy of developing cotton fibers (Gossypium hirsutum) is tightly associated with the plasma membrane. Therefore, this form of SuSy might serve to channel carbon directly from sucrose to cellulose and/or callose synthases in the plasma membrane. By using detached and permeabilized cotton fibers, we show that carbon from sucrose can be converted at high rates to both cellulose and callose. Synthesis of cellulose or callose is favored by addition of EGTA or calcium and cellobiose, respectively. These findings contrast with the traditional observation that when UDPglucose is used as substrate in vitro, callose is the major product synthesized. Immunolocalization studies show that SuSy can be localized at the fiber surface in patterns consistent with the deposition of cellulose or callose. Thus, these results support a model in which SuSy exists in a complex with the beta-glucan synthases and serves to channel carbon from sucrose to glucan.}, number={20}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={AMOR, Y and HAIGLER, CH and JOHNSON, S and WAINSCOTT, M and DELMER, DP}, year={1995}, month={Sep}, pages={9353–9357} }
 @article{roberts_haigler_1994, title={CELL EXPANSION AND TRACHEARY ELEMENT DIFFERENTIATION ARE REGULATED BY EXTRACELLULAR PH IN MESOPHYLL CULTURES OF ZINNIA-ELEGANS L}, volume={105}, ISSN={["0032-0889"]}, DOI={10.1104/pp.105.2.699}, abstractNote={The effects of medium pH on cell expansion and tracheary element (TE) differentiation were investigated in differentiating mesophyll suspension cultures of Zinnia elegans L. In unbuffered cultures initially adjusted to pH 5.5, the medium pH fluctuated reproducibly, decreasing about 1 unit prior to the onset of TE differentiation and then increasing when the initiation of new Tes was complete. Elimination of large pH fluctuations by buffering the culture medium with 20 mM 2-(N-morpholino)ethanesulfonic acid altered both cell expansion and TE differentiation, whereas altering the starting pH of unbuffered culture medium had no effect on either process. Cell expansion in buffered cultures was pH dependent with an optimum of 5.5 to 6.0. The direction of cell expansion was also pH dependent in buffered cultures. Cells elongated at pH 5.5 to 6.0, whereas isodiametric cell expansion was predominant at pH 6.5 to 7.0. The onset of TE differentiation was delayed when the pH was buffered higher or lower than 5.0. However, TEs eventually appeared in cultures buffered at pH 6.5 to 7.0, indicating that a decrease in pH to 5.0 is not necessary for differentiation. Very large TEs with secondary cell wall thickenings resembling metaxylem differentiated in cultures buffered at pH 5.5 to 6.0, which also showed the greatest cell expansion. The correlation between cell expansion and delayed differentiation of large, metaxylem-like TEs may indicate a link between the regulatory mechanisms controlling cell expansion and TE differentiation.}, number={2}, journal={PLANT PHYSIOLOGY}, author={ROBERTS, AW and HAIGLER, CH}, year={1994}, month={Jun}, pages={699–706} }
 @article{haigler_1994, title={FROM SIGNAL-TRANSDUCTION TO BIOPHYSICS - TRACHEARY ELEMENT DIFFERENTIATION AS A MODEL SYSTEM}, volume={155}, ISSN={["1058-5893"]}, DOI={10.1086/297164}, abstractNote={The three review articles that follow deal with an important research area. They address the processes by which cells become competent for, then committed to, a terminal differentiation pathway culminating in cell death. More specifically, they address the formation of a plant cell type-tracheary elements-that is essential for plant function, environmental adaptation, and the economic uses of wood. Tracheary element differentiation within the xylem tissue to form water-conducting pathways is characterized by the deposition of strong secondary cell walls followed by autolysis of the cytoplasm. The secondary cell wall thickenings contain ordered cellulose, xylan, protein, and lignin, and they are deposited in precise patterns on the extracytoplasmic side of the plasma membrane. Secondary wall deposition must involve the endomembrane system (including vesicle targeting, exocytosis, and membrane retrieval), specialized plasma membrane domains, cytoskeletal elements, changes in gene expression, activities of numerous enzymes, and biophysical processes as related to intracellular gradients, membrane properties, and cell wall assembly. However, we do not know how all of these lements are coordinated. In perennial plants with secondary growth, tracheary elements from previous years accumulate and contribute to the formation of wood. Tracheary element number, size, and extent of wall thickening help determine plant adaptability to particular habitats and the economic properties of wood. Therefore, for both basic and applied reasons, understanding how tracheary element differentiation is regulated is of paramount importance in plant biology. As indicated by the diverse specimens emphasized by each reviewer, including differentiation in vivo in temperate zone hardwoods (Catesson), detached stem segments of Pinus contorta (Savidge), and isolated mesophyll cells of Zinnia elegans (Fukuda), the potential of this research area is enhanced by the availability for study of several experimental systems, including in vitro systems. Other laboratories are determining biochemical and molecular mechanisms relevant o xylem differentiation i intact Pinus trees (Bao et al. 1992; O'Malley et al. 1993), in Pinus suspension cultures (Eberhardt et al. 1993), and in plants amenable to genetic analysis, such as Arabidopsis (Chapple et al. 1992). In addition, many classic systems exist for induction and manipulation of tracheary element differentiation in vitro (Roberts 1976; and summarized by Fukuda). The ease with which tracheary element differentiation ca be induced in vitro probably reflects he potential of most parenchyma cells to enter this pathway if required to make an alternate water conduit after injury to the xylem tissue. It is appropriate that research be continued on several differentiating cell systems because each has varying strengths interms of amenability to biochemical, microscopical, molecular, and genetic analyses. Also, it is only by eventually comparing the details of relevant mechanisms in several cell systems that we can come to understand the extent to which certain physiological events are essential in all examples, including differentiation from procambium, vascular cambium, and parenchyma cells after wounding. An understanding of commonality and divergence of regulatory mechanisms will provide the most insight into this fascinating cell biological process and the most potential for intelligent manipulation of tracheary element differentiation for future plant improvement. An outstanding question is whether there is a common cell differentiation state that indicates commitment to become a tracheary element. In his discussion, Fukuda presents one hypothesis about stages through which a cell might pass during redifferentiation in vitro from isolated parenchyma cells. If a common progenitor cell type does exist, it might reasonably be expected that signal transduction mechanisms before that stage and some enzymes induced after that stage (e.g., for synthesis of particular matrix proteins, polysaccharides, or lignin precursors) would differ somewhat depending on the mode of induction, position, and fate of the particular tracheary element. The difficulty of coming to a definitive understanding of signal transduction mechanisms, including their interface with regulation by auxin, cytokinin, and other factors uch as ion and pH gradients, is emphasized by the work of Savidge on Pinus stem segments. Through his research, the existence of an additional factor equired to induce tracheary element differentiation has been proposed. More research effort should be extended in this area, particularly after the establishment of liaisons with experts in signal transduction sothat experiments and analyses are consistent with the most advanced knowledge in this complex research area. All three reviews also emphasize the need to}, number={3}, journal={INTERNATIONAL JOURNAL OF PLANT SCIENCES}, author={HAIGLER, CH}, year={1994}, month={May}, pages={248–250} }
 @inproceedings{haigler_taylor_martin_1994, title={Temperature dependence of fiber cellulose biosynthesis: Impact on fiber maturity and strength}, booktitle={Proceedings of the Biochemistry of Cotton Workshop, Galveston, TX, Sept. 28-30}, publisher={Raleigh, NC: Cotton Incorporated}, author={Haigler, C. H. and Taylor, J. G. and Martin, L. K.}, year={1994}, pages={95–100} }
 @article{xie_trolinder_haigler_1993, title={Cool temperature effects on cotton fiber initiation and elongation clarified using in vitro cultures}, volume={33}, DOI={10.2135/cropsci1993.0011183x003300060029x}, abstractNote={An understanding of the mechanistic basis of adverse environmental effects on cotton fiber development is a prerequisite to future improvement through genetic engineering and aids in field management to minimize such adverse effects. In order to clarify previous results from field studies on the effects of cool temperatures on initiation, early elongation, and later elongation of cotton fibers, cotton ovules (Gossypium hirsutum L.) cultured in vitro were used as a manipulable and reproducible experimental system based on previous evidence that they provide a valid model. Culture temperature varied from a control of 34 °C constant to 34/15 °C cycling (12/12 h) to mimic a typical diurnal temperature cycle. Fiber initiation and early elongation were analyzed by scanning electron microscopy, and the progress of later elongation was determined by ruler measurements. The results demonstrated that fiber initiation and early elongation (up to about 0.5‐mm length) were independently delayed by cycling cool temperatures, but that later elongation preceded in a temperature‐independent manner. The early delay in fiber development caused by cycling cool temperatures was associated with a longer elongation period during which fibers could attain the control length. Therefore, the results suggest that there are three stages of fiber elongation as distinguished by different temperature responses: initiation, early elongation, and later elongation to attain the genetically determined potential. Consequently, the field temperature during fiber initiation and early elongation may have a profound effect on the final fiber length attained in a limited growing season.}, journal={Crop Science}, author={Xie, W. and Trolinder, N. L. and Haigler, Candace H.}, year={1993}, pages={1258–1264} }
 @article{taylor_haigler_1993, title={Patterned secondary wall assembly in tracheary elements occurs in a self-perpetuating cascade}, volume={42}, DOI={10.1111/j.1438-8677.1993.tb00692.x}, abstractNote={The behaviours are presented of newly-synthesized xylan and putative glycine-rich protein during patterned secondary cell-wall biogenesis in drug-treated tracheary elements (TEs) differentiating in culture from isolated mesophyll cells of Zinnia elegans. The normal secondary wall thickenings contain cellulose, xylan, and lignin, and the results reported here suggest that they also contain glycine-rich protein (GRP). However, qualifications to this definitive interpretation are discussed. The specific cellulose synthesis inhibitors, 2,6-dichlorobenzonitrile (DCB) and isoxaben, were applied near the onset of differentiation. When they were fully effective in inhibiting deposition of detectable cellulose in the thickenings, no labelling of the thickenings was observed with probes for xylan (xylanase and an antibody to xylose) or GRP (an antibody)}, journal={Acta Botanica Neerlandica}, author={Taylor, J. G. and Haigler, Candace H.}, year={1993}, pages={153–163} }
 @article{roberts_koonce_haigler_1992, title={A SIMPLIFIED MEDIUM FOR INVITRO TRACHEARY ELEMENT DIFFERENTIATION IN MESOPHYLL SUSPENSION-CULTURES FROM ZINNIA-ELEGANS L}, volume={28}, ISSN={["0167-6857"]}, DOI={10.1007/BF00039912}, number={1}, journal={PLANT CELL TISSUE AND ORGAN CULTURE}, author={ROBERTS, AW and KOONCE, LT and HAIGLER, CH}, year={1992}, month={Jan}, pages={27–35} }
 @article{taylor_owen_koonce_haigler_1992, title={DISPERSED LIGNIN IN TRACHEARY ELEMENTS TREATED WITH CELLULOSE SYNTHESIS INHIBITORS PROVIDES EVIDENCE THAT MOLECULES OF THE SECONDARY CELL-WALL MEDIATE WALL PATTERNING}, volume={2}, ISSN={["0960-7412"]}, DOI={10.1111/j.1365-313X.1992.00959.x}, abstractNote={SummaryMesophyll cells of Zinnia elegans var. Envy that had been induced to differentiate into tracheary elements (TEs) in suspension culture were treated with the cellulose synthesis inhibitor 2,6‐dichlorobenzonitrile (DCB). The deposition of cellulose into the patterned secondary cell wall thickenings typical of TEs was inhibited as demonstrated by reduced incorporation of [14C]glucose into acetic/nitric insoluble material and absence of cellulose detectable by fluorescence after staining with Tinopal LPW, polarization optics, or labeling with a specific cellulase. Respiration as indicated by release of 14CO2 was inhibited to a much lesser extent, supporting a selective mechanism of action of DCB on the cellulose biosynthetic pathway. Patterned secondary cell wall thickenings were deposited in DCB‐treated TEs, but these were smaller and less regularly shaped than those of control TEs. These cellulose‐depleted thickenings lacked another abundant component of normal thickenings, the hemicellulose xylan, as indicated by absence of labeling with a specific xylanase or an antibody to xylan. DCB‐treated TEs also showed dispersed lignin after staining with phloroglucinol, whereas control TEs contained lignin specifically localized to the secondary cell wall thickenings. Isoxaben, another recently described inhibitor of synthesis of acetic/nitric insoluble cell wall material (putatively cellulose), caused the same absence of detectable cellulose and xylan in the thickenings and dispersed lignin. These data suggest that: (i) the localization of lignin is ultimately dependent on the localization of cellulose; (ii) normal patterned wall assembly in TEs occurs in a self‐perpetuating cascade in which some molecules of the secondary cell wall mediate patterning of others.}, number={6}, journal={PLANT JOURNAL}, author={TAYLOR, JG and OWEN, TP and KOONCE, LT and HAIGLER, CH}, year={1992}, month={Nov}, pages={959–970} }
 @article{roberts_rao_huang_trolinder_haigler_1992, title={EFFECTS OF CYCLING TEMPERATURES ON FIBER METABOLISM IN CULTURED COTTON OVULES}, volume={100}, ISSN={["0032-0889"]}, DOI={10.1104/pp.100.2.979}, abstractNote={The effects of temperature on rates of cellulose synthesis, respiration, and long-term glucose uptake were investigated using cultured cotton ovules (Gossypium hirsutum L. cv Acala SJ1). Ovules were cultured either at constant 34 degrees C or under cycling temperatures (12 h at 34 degrees C/12 h at 15-40 degrees C). Rates of respiration and cellulose synthesis at various temperatures were determined on day 21 during the stage of secondary wall synthesis by feeding cultured ovules with [(14)C]glucose. Respiration increased between 18 and approximately 34 degrees C, then remained constant up to 40 degrees C. In contrast, the rate of cellulose synthesis increased above 18 degrees C, reached a plateau between about 28 and 37 degrees C, and then decreased at 40 degrees C. Therefore, the optimum temperature for rapid and metabolically efficient cellulose synthesis in Acala SJ1 is near 28 degrees C. In ovules cycled to 15 degrees C, respiration recovered to the control rate immediately upon rewarming to 34 degrees C, but the rate of cellulose synthesis did not fully recover for several hours. These data indicate that cellulose synthesis and respiration respond differently to cool temperatures. The long-term uptake of glucose, which is the carbon source in the culture medium, increased as the low temperature in the cycle increased between 15 and 28 degrees C. However, glucose uptake did not increase in cultures grown constantly at 34 degrees C compared to those cycled at 34/28 degrees C. These observations are consistent with previous observations on the responses of fiber elongation and weight gain to cycling temperatures in vitro and in the field.}, number={2}, journal={PLANT PHYSIOLOGY}, author={ROBERTS, EM and RAO, NR and HUANG, JY and TROLINDER, NL and HAIGLER, CH}, year={1992}, month={Oct}, pages={979–986} }
 @article{roberts_haigler_1992, title={Methylxanthines reversibly inhibit tracheary element differentiation in suspension cultures of Zinnia elegans}, volume={186}, DOI={10.1007/bf00198040}, abstractNote={Tracheary-element (TE) differentiation in suspension-cultured mesophyll cells of Zinnia elegans L. was completely inhibited by caffeine and theophylline only when these methylxanthines were applied at least 8 h prior to the appearance of secondary cell-wall thickenings. In contrast, the calcium-channel blocker nifedipine completely inhibited TE differentiation when applied only 2-3 h prior to the onset of secondary cell-wall deposition. This indicates the involvement of a methylxanthine-inhibitable event in TE differentiation that is distinguishable from an event dependent on influx of extracellular calcium. The correlation between the time of appearance of chlorotetracycline fluorescence (an indicator of sequestered Ca(2+)) and loss of methylxanthine effectiveness indicates that inhibition by methylxanthines may result from release of Ca(2+) from intracellular stores. Methylxanthines with high potencies against adenosine 3' ∶ 5'-cyclic monophosphate (cAMP) phosphodiesterase and adenosine receptors were less effective inhibitors of TE differentiation, indicating that inhibition of differentiation by methylxanthines is independent of cAMP metabolism. The role of cAMP in transduction of the cytokinin signal, which was proposed previously on the basis of stimulation of TE differentiation by theophylline, was investigated using the non-hydrolyzable analog 8-bromo-cAMP. Although 8-bromo-cAMP stimulated differentiation in the absence of inductive concentrations of cytokinin, the non-cyclic analog 8-bromo-AMP was even more effective, indicating that 8-bromo-cAMP behaves as a cytokinin analog, rather than a second messenger, in stimulating TE differentiation.}, journal={Planta (Online)}, author={Roberts, A. W. and Haigler, Candace H.}, year={1992}, pages={586–592} }
 @inproceedings{haigler_1992, title={The crystallinity of cotton cellulose in relation to cotton improvement}, booktitle={Proceedings, Cotton Fiber Cellulose: Structure, Function, and Utilization Conference}, publisher={Memphis, TN: National Cotton Council of America}, author={Haigler, C. H.}, year={1992}, pages={211–225} }
 @article{shang_huang_haigler_trolinder_1991, title={Buffer capacity of cotton cells and effects of extracellular pH on growth and somatic embryogenesis in cotton cell suspensions}, volume={27P}, DOI={10.1007/bf02632199}, journal={In Vitro Cellular & Developmental Biology. Plant}, author={Shang, X. M. and Huang, J. Y. and Haigler, Candace H. and Trolinder, N. L.}, year={1991}, pages={147–152} }
 @article{haigler_rao_roberts_huang_upchurch_trolinder_1991, title={CULTURED OVULES AS MODELS FOR COTTON FIBER DEVELOPMENT UNDER LOW-TEMPERATURES}, volume={95}, ISSN={["0032-0889"]}, DOI={10.1104/pp.95.1.88}, abstractNote={Cotton fibers (Gossypium hirsutum L.) developing in vitro responded to cyclic temperature change similarly to those of field-grown plants under diumal temperature fluctuations. Absolute temperatures and rates of temperature change were similar under both conditions. In vitro fibers exhibited a "growth ring" for each time the temperature cycled to 22 or 15 degrees C. Rings were rarely detected when the low point was 28 degrees C. The rings seemed to correspond to alternating regions of high and low cellulose accumulation. Fibers developed in vitro under 34 degrees C/22 degrees C cycling developed similarly to constant 34 degrees C controls, but 34 degrees C/22 degrees C and 34 degrees C/15 degrees C cycling caused delayed onset and prolonged periods of elongation and secondary wall thickening. Control fiber length and weight were finally achieved under 34 degrees C/22 degrees C cycling, but both parameters were reduced at the end of the experiment under 34 degrees C/15 degrees C cycling. Fibers developed under all conditions had equal bundle tensile strength. These results demonstrate that: (a) cool temperature effects on fiber development are at least partly fiber/ovule-specific events; they do not depend on whole-plant physiology; and (b) cultured ovules are valid models for research on the regulation of the field cool temperature response.}, number={1}, journal={PLANT PHYSIOLOGY}, author={HAIGLER, CH and RAO, NR and ROBERTS, EM and HUANG, JY and UPCHURCH, DR and TROLINDER, NL}, year={1991}, month={Jan}, pages={88–96} }
 @inbook{haigler_1991, title={The relationship between polymerization and crystallization in cellulose biogenesis}, ISBN={0824783875}, booktitle={Biosynthesis and biodegradation of cellulose}, publisher={New York: Marcel Dekker}, author={Haigler, C. H.}, editor={Haigler, C. H. and Weimer, P.Editors}, year={1991}, pages={99–124} }
 @inbook{haigler_1990, place={New York}, title={Relationship between polymerization and crystallization in microfibril biogenesis}, ISBN={0-8247-8387-5}, booktitle={Biosynthesis and Biodegradation of Cellulose}, publisher={Marcel Dekker}, author={Haigler, C.H.}, editor={Haigler, C.H. and Weimer, PEditors}, year={1990}, month={Dec}, pages={99–124} }
 @article{roberts_haigler_1990, title={TRACHEARY-ELEMENT DIFFERENTIATION IN SUSPENSION-CULTURED CELLS OF ZINNIA REQUIRES UPTAKE OF EXTRACELLULAR CA-2+ - EXPERIMENTS WITH CALCIUM-CHANNEL BLOCKERS AND CALMODULIN INHIBITORS}, volume={180}, ISSN={["1432-2048"]}, DOI={10.1007/bf02411447}, abstractNote={Tracheary-element (TE) differentiation in suspension cultures ofZinnia elegans L. mesophyll cells was inhibited by blocking calcium uptake in three ways: 1) reducing the [Ca(2+)] of the culture medium, 2) blocking calcium channels with the non-permeant cation La(3+), and 3) blocking calcium channels with permeant dihydropyridine calcium-channel blockers. Calcium-channel blockers were effective when added at any time between 0 and 48 h after culture initiation; after 48h, calcium sequestration and secondary cell-wall deposition began. In contrast, calmodulin antagonists inhibited TE differentiation when added at the beginning of culture, but not when added after 24h. These results indicate that TE differentiation involves at least two calcium-regulated events: one calmodulin-dependent and occurring shortly after exposure to inductive conditions, and the other calmodulin-independent and occurring just prior to secondary cell-wall deposition.}, number={4}, journal={PLANTA}, author={ROBERTS, AW and HAIGLER, CH}, year={1990}, month={Mar}, pages={502–509} }
 @inbook{haigler_chanzy_1989, title={Electron diffraction analysis of altered cellulose: Implications for mechanisms of biogenesis}, ISBN={0471512567}, booktitle={Cellulose and wood: Chemistry and technology}, publisher={New York: John Wiley}, author={Haigler, C. H. and Chanzy, H.}, year={1989}, pages={493–506} }
 @article{roberts_haigler_1989, title={Rise in chlorotetracycline fluorescence accompanies tracheary element differentiation in suspension cultures of Zinnia}, volume={152}, DOI={10.1007/BF01354238}, journal={Protoplasma}, author={Roberts, A. W. and Haigler, Candace H.}, year={1989}, pages={37–45} }
 @inproceedings{haigler_roberts_1989, title={Structural aspects of tracheary element differentiation in suspension cultures of Zinnia elegans}, booktitle={Proceedings of the 47th Annual Meeting of the Electron Microscopy Society of America}, publisher={San Francisco, CA: San Francisco Press}, author={Haigler, C. H. and Roberts, A. W.}, year={1989}, pages={768–769} }
 @article{haigler_chanzy_1988, title={ELECTRON-DIFFRACTION ANALYSIS OF THE ALTERED CELLULOSE SYNTHESIZED BY ACETOBACTER-XYLINUM IN THE PRESENCE OF FLUORESCENT BRIGHTENING AGENTS AND DIRECT DYES}, volume={98}, ISSN={["0889-1605"]}, DOI={10.1016/S0889-1605(88)80922-4}, abstractNote={The crystalline structures of the altered cellulose synthesized by Acetobacter xylinum in the presence of a fluorescent brightening agent and several direct dyes were investigated by electron and X-ray diffraction. The results indicate that amorphous cellulose is synthesized in mixture with a precipitate of the altering agent. A diffraction line at 0.399 nm attributable to ordered stacking of the altering agent is recorded when cellulose is synthesized in the presence of three direct dyes and Fluorescent Brightening Agent 28 (FBA 28). No crystallinity could be recorded from samples synthesized in the presence of four other direct dyes. Cellulose I was formed when the altering agent was removed by washing from FBA 28-induced samples, but the crystallite size was reduced compared to that of control bacterial cellulose. These results are discussed in terms of the ultra-structure of modified cellulose and the tendency of direct dyes and fluorescent brightening agents to aggregate.}, number={3}, journal={JOURNAL OF ULTRASTRUCTURE AND MOLECULAR STRUCTURE RESEARCH}, author={HAIGLER, CH and CHANZY, H}, year={1988}, month={Mar}, pages={299–311} }
 @article{raikhel_palevitz_haigler_1986, title={ABSCISIC-ACID CONTROL OF LECTIN ACCUMULATION IN WHEAT SEEDLINGS AND CALLUS-CULTURES - EFFECTS OF EXOGENOUS ABA AND FLURIDONE}, volume={80}, ISSN={["1532-2548"]}, DOI={10.1104/pp.80.1.167}, abstractNote={Wheat germ agglutinin is found in wheat embryos and a similar lectin is present in the roots of older plants. We report here that 10 micromolar abscisic acid (ABA) produces an average two to three-fold enhancement in the amount of lectin in the shoot base and the terminal portion of the root system of hydroponically grown wheat seedlings. Although ABA stunts seedling growth, a similar growth inhibition produced by ancymidol is not accompanied by elevated lectin levels. To further clarify the role of ABA, wheat callus cultures were employed. Callus derived from immature embryos was grown on growth medium containing various combinations of ABA and 2,4-dichlorophenoxyacetic acid. Those grown in the presence of 10 micromolar ABA exhibit the largest increases in lectin compared to material grown on other regimes. The involvement of ABA in lectin accumulation was further probed with fluridone, an inhibitor of carotenoid synthesis which has also been linked to depressed levels of endogenous ABA. Wheat seedlings grown in the presence of 1 or 10 milligrams per liter fluridone have few or no carotenoids, and wheat germ agglutinin levels in the shoot base and roots are lower compared to controls. The greatest effect (a 39% reduction in the shoot base) is produced at an herbicide concentration of 10 milligrams per liter. Exogenous 10 micromolar ABA greatly stimulates lectin accumulation in the presence of fluridone, but the levels are not as high as those produced by ABA alone. These results indicate that lectin synthesis is under ABA control in both wheat embryos and adult plants.}, number={1}, journal={PLANT PHYSIOLOGY}, author={RAIKHEL, NV and PALEVITZ, BA and HAIGLER, CH}, year={1986}, month={Jan}, pages={167–171} }
 @article{haigler_brown_1986, title={TRANSPORT OF ROSETTES FROM THE GOLGI-APPARATUS TO THE PLASMA-MEMBRANE IN ISOLATED MESOPHYLL-CELLS OF ZINNIA-ELEGANS DURING DIFFERENTIATION TO TRACHEARY ELEMENTS IN SUSPENSION-CULTURE}, volume={134}, ISSN={["1615-6102"]}, DOI={10.1007/BF01275709}, number={2-3}, journal={PROTOPLASMA}, author={HAIGLER, CH and BROWN, RM}, year={1986}, pages={111–120} }
 @inbook{haigler_1985, title={The functions and biogenesis of native cellulose}, ISBN={0853124639}, booktitle={Cellulose chemistry and its applications}, publisher={Chichester, Eng.: Ellis Horwood}, author={Haigler, C. H.}, year={1985}, pages={30–83} }
 @inbook{brown_haigler_suttie_white_roberts_smith_itoh_cooper_1983, title={The biosynthesis and degradation of cellulose. (Journal of applied polymer science. Applied polymer symposium; 37)}, ISBN={0471881325}, booktitle={Proceedings of the Ninth Cellulose Conference: held at Syracuse, New York, May 24-27, 1982}, publisher={New York: Wiley}, author={Brown, R. M., Jr. and Haigler, C. H. and Suttie, J. and White, A. and Roberts, E. and Smith, C. and Itoh, T. and Cooper, C.}, year={1983}, pages={33–78} }
 @article{roberts_seagull_haigler_brown_1982, title={ALTERATION OF CELLULOSE MICROFIBRIL FORMATION IN EUKARYOTIC CELLS - CALCOFLUOR WHITE INTERFERES WITH MICROFIBRIL ASSEMBLY AND ORIENTATION IN OOCYSTIS-APICULATA}, volume={113}, ISSN={["0033-183X"]}, DOI={10.1007/BF01283034}, number={1}, journal={PROTOPLASMA}, author={ROBERTS, E and SEAGULL, RW and HAIGLER, CH and BROWN, RM}, year={1982}, pages={1–9} }
 @article{haigler_white_brown_cooper_1982, title={ALTERATION OF INVIVO CELLULOSE RIBBON ASSEMBLY BY CARBOXYMETHYLCELLULOSE AND OTHER CELLULOSE DERIVATIVES}, volume={94}, ISSN={["0021-9525"]}, DOI={10.1083/jcb.94.1.64}, abstractNote={In vivo cellulose ribbon assembly by the Gram-negative bacterium Acetobacter xylinum can be altered by incubation in carboxymethylcellulose (CMC), a negatively charged water-soluble cellulose derivative, and also by incubation in a variety of neutral, water-soluble cellulose derivatives. In the presence of all of these substituted celluloses, normal fasciation of microfibril bundles to form the typical twisting ribbon is prevented. Alteration of ribbon assembly is most extensive in the presence of CMC, which often induces synthesis of separate, intertwining bundles of microfibrils. Freeze-etch preparations of the bacterial outer membrane suggest that particles that are thought to be associated with cellulose synthesis or extrusion may be specifically organized to mediate synthesis of microfibril bundles. These data support the previous hypothesis that the cellulose ribbon of A. xylinum is formed by a hierarchical, cell-directed, self-assembly process. The relationship of these results to the regulation of cellulose microfibril size and wall extensibility in plant cell walls is discussed.}, number={1}, journal={JOURNAL OF CELL BIOLOGY}, author={HAIGLER, CH and WHITE, AR and BROWN, RM and COOPER, KM}, year={1982}, pages={64–69} }
 @inbook{haigler_benziman_1982, title={Biogenesis of cellulose I microfibrils occurs by cell-directed self-assembly in Acetobacter xylinum}, ISBN={0306408562}, DOI={10.1007/978-1-4684-1116-4_14}, booktitle={Cellulose and other natural polymer systems}, publisher={New York: Plenum Press}, author={Haigler, Candace H. and Benziman, M.}, year={1982}, pages={273–296} }
 @article{brown_haigler_cooper_1982, title={EXPERIMENTAL INDUCTION OF ALTERED NON-MICROFIBRILLAR CELLULOSE}, volume={218}, ISSN={["0036-8075"]}, DOI={10.1126/science.218.4577.1141}, abstractNote={
            Cellulose produced by
            Acetobacter xylinum
            was experimentally modified during its biosynthesis. In the presence of fluorescent brightening agents, such as Calcofluor White M2R or Tinopal LPW, nonmicrofibrillar sheets of cellulose were synthesized by the bacteria. These sheets could then be converted to fibrils by washing with distilled water. Possible mechanisms for these modifications of cellulose assembly are discussed.
          }, number={4577}, journal={SCIENCE}, author={BROWN, RM and HAIGLER, C and COOPER, K}, year={1982}, pages={1141–1142} }
 @inproceedings{haigler_brown_1981, title={Probing the relationship of polymerization and crystallization in the biogenesis of cellulose}, ISBN={9186018051}, booktitle={The Ekman-Days 1981: International Symposium on Wood and Pulping Chemistry, Stockholm, June 9-12, 1981}, publisher={Stockholm: Swedish Paper Chemistry Institute}, author={Haigler, C. H. and Brown, R. M.}, year={1981} }
 @article{haigler_malcolmbrown_benziman_1980, title={CALCOFLUOR WHITE ST ALTERS THE INVIVO ASSEMBLY OF CELLULOSE MICROFIBRILS}, volume={210}, ISSN={["0036-8075"]}, DOI={10.1126/science.7434003}, abstractNote={
            The fluorescent brightener, Calcofluor White ST, prevents the in vivo assembly of crystalline cellulose microfibrils and ribbons by Acetobacter xylinum. In the presence of more than 0.01 percent Calcofluor, Acetobacter continues to synthesize high-molecular-weight β-1,4 glucans. X-ray crystallography shows that the altered product exhibits no detectable crystallinity in the wet state, but upon drying it changes into crystalline cellulose I. Calcofluor alters cellulose crystallization by hydrogen bonding with glucan chains. Synthesis of this altered product is reversible and can be monitored with fluorescence and electron microscopy. Use of Calcofluor has made it possible to separate the processes of polymerization and crystallization leading to the biogenesis of cellulose microfibrils, and has suggested that crystallization occurs by a cell-directed, self-assembly process in
            Acetobacter xylinum
            .
          }, number={4472}, journal={SCIENCE}, author={HAIGLER, CH and MALCOLMBROWN, R and BENZIMAN, M}, year={1980}, pages={903–906} }
 @article{benziman_haigler_brown_white_cooper_1980, title={CELLULOSE BIOGENESIS - POLYMERIZATION AND CRYSTALLIZATION ARE COUPLED PROCESSES IN ACETOBACTER-XYLINUM}, volume={77}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.77.11.6678}, abstractNote={
            Calcofluor White ST, stilbene derivative used commerically as an optical brightener for cellulose, increased the rate of glucose polymerization into cellulose by resting cells of the gram-negative bacterium
            Acetobacter xylinum
            . This bacterium normally produces a ribbon of cellulose that is a composite of crystalline microfibrils. In concentrations above 0.1 mM, Calcofluor disrupts the assembly of crystalline cellulose I microfibrils and their integration into a composite ribbon by stoichiometric binding to glucose residues of newly polymerized glucan chains. Under these conditions, the rate of glucose polymerization increases up to 4 times the control rate, whereas oxygen uptake increases only 10-15%. These observed effects are readily reversible. If free Calcofluor is washed away or depleted below the threshold value by binding to cellulose as polymerization continues, ribbon production and the normal rate of polymerization resume. It is concluded that polymerization and crystallization are cell-directed, coupled processes and that the rate of crystallization determines the rate of polymerization. It is suggested that coupling must be maintained for biogenesis of crystalline cellulose I.
          }, number={11}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES}, author={BENZIMAN, M and HAIGLER, CH and BROWN, RM and WHITE, AR and COOPER, KM}, year={1980}, pages={6678–6682} }