@article{dewey_selote_griffin_dickey_jantz_smith_matthiadis_strable_kestell_smith_2023, title={Cytoplasmic male sterility and abortive seed traits generated through mitochondrial genome editing coupled with allotopic expression of atp1 in tobacco}, volume={14}, ISSN={["1664-462X"]}, DOI={10.3389/fpls.2023.1253640}, abstractNote={Allotopic expression is the term given for the deliberate relocation of gene function from an organellar genome to the nuclear genome. We hypothesized that the allotopic expression of an essential mitochondrial gene using a promoter that expressed efficiently in all cell types except those responsible for male reproduction would yield a cytoplasmic male sterility (CMS) phenotype once the endogenous mitochondrial gene was inactivated via genome editing. To test this, we repurposed the mitochondrially encoded atp1 gene of tobacco to function in the nucleus under the transcriptional control of a CaMV 35S promoter (construct 35S:nATP1), a promoter that has been shown to be minimally expressed in early stages of anther development. The endogenous atp1 gene was eliminated (Δatp1) from 35S:nATP1 tobacco plants using custom-designed meganucleases directed to the mitochondria. Vegetative growth of most 35S:nATP1/Δatp1 plants appeared normal, but upon flowering produced malformed anthers that failed to shed pollen. When 35S:nATP1/Δatp1 plants were cross-pollinated, ovary/capsule development appeared normal, but the vast majority of the resultant seeds were small, largely hollow and failed to germinate, a phenotype akin to the seedless trait known as stenospermocarpy. Characterization of the mitochondrial genomes from three independent Δatp1 events suggested that spontaneous recombination over regions of microhomology and substoichiometric shifting were the mechanisms responsible for atp1 elimination and genome rearrangement in response to exposure to the atp1-targeting meganucleases. Should the results reported here in tobacco prove to be translatable to other crop species, then multiple applications of allotopic expression of an essential mitochondrial gene followed by its elimination through genome editing can be envisaged. Depending on the promoter(s) used to drive the allotopic gene, this technology may have potential application in the areas of: (1) CMS trait development for use in hybrid seed production; (2) seedless fruit production; and (3) transgene containment.}, journal={FRONTIERS IN PLANT SCIENCE}, author={Dewey, Ralph E. and Selote, Devarshi and Griffin, H. Carol and Dickey, Allison N. and Jantz, Derek and Smith, J. Jeff and Matthiadis, Anna and Strable, Josh and Kestell, Caitlin and Smith, William A.}, year={2023}, month={Sep} }
 @article{bovet_campanoni_lu_hilfiker_kleinhans_laparra_schwaar_lewis_matsuba_ma_et al._2022, title={CLCNt2 Mediates Nitrate Content in Tobacco Leaf, Impacting the Production of Tobacco-Specific Nitrosamines in Cured Leaves}, volume={13}, ISSN={["1664-462X"]}, DOI={10.3389/fpls.2022.741078}, abstractNote={Nitrate accumulation in tobacco (Nicotiana tabacum L.) leaf, particularly in the burley (BU) type, is a reservoir for the generation of nitrosating agents responsible for the formation of tobacco-specific nitrosamines (TSNAs). TSNAs are mainly produced via the nitrosation of alkaloids occurring during the curing of tobacco leaves. Additional formation of TSNAs may also occur during tobacco storage, leaf processing and in some circumstances via pyrosynthesis during combustion. Two TSNA species, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN) are found in the tobacco products and have been documented to be animal carcinogens. A previous study showed that decreasing the accumulation of nitrate in tobacco leaf via the overexpression of a deregulated form of nitrate reductase is efficient to reduce the production of TSNAs. We pursue in finding another molecular genetic target to lower nitrate in BU tobacco. Suppressing expression or knocking-out CLCNt2 has a direct impact on leaf nitrate and TSNA reduction in cured leaves without altering biomass. This study provides now a straight path toward the development of new commercial tobacco varieties with reduced TSNA levels by breeding of variants deficient in active CLCNt2 copies.}, journal={FRONTIERS IN PLANT SCIENCE}, author={Bovet, Lucien and Campanoni, Prisca and Lu, Jian and Hilfiker, Aurore and Kleinhans, Samuel and Laparra, Helene and Schwaar, Joanne and Lewis, Ramsey S. and Matsuba, Yuki and Ma, Hong and et al.}, year={2022}, month={Feb} }
 @article{smith_matsuba_dewey_2022, title={Knockout of a key gene of the nicotine biosynthetic pathway severely affects tobacco growth under field, but not greenhouse conditions}, volume={15}, ISSN={["1756-0500"]}, DOI={10.1186/s13104-022-06188-9}, abstractNote={Abstract}, number={1}, journal={BMC RESEARCH NOTES}, author={Smith, William A. and Matsuba, Yuki and Dewey, Ralph E.}, year={2022}, month={Sep} }
 @article{lu_chandrakanth_lewis_andres_bovet_goepfert_dewey_2021, title={Constitutive activation of nitrate reductase in tobacco alters flowering time and plant biomass}, volume={11}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-021-83797-7}, abstractNote={Abstract}, number={1}, journal={SCIENTIFIC REPORTS}, author={Lu, Jianli and Chandrakanth, Niharika N. and Lewis, Ramsey S. and Andres, Karen and Bovet, Lucien and Goepfert, Simon and Dewey, Ralph E.}, year={2021}, month={Feb} }
 @article{lin_dewey_wang_yu_long_zhang_yu_zhang_wang_ren_2021, title={Discovery of a naturally-occurring allele of eIF4E1.S in Nicotiana tabacum and development of a co-dominant marker}, volume={217}, ISSN={["1573-5060"]}, DOI={10.1007/s10681-021-02876-y}, abstractNote={Potato virus Y (PVY) is one of the most problematic pathogens affecting tobacco production. Genetic resistance to PVY in cultivated tobacco is mediated by recessive mutations, including the locus designated VAM, and its derived mutant va, both of which were previously shown to contain large chromosomal deletions. Among the genes deleted in lines containing VAM or va is eIF4E1.S, a gene whose protein product has been shown to facilitate infection by certain potyviruses, including PVY. Because the extent of the deletions and the exact nature of their specific breakpoints have not been precisely established for VAM or va, it has not been possible to develop co-dominant markers to facilitate their transfer to elite varieties using molecular breeding technologies. Here, we report the discovery of a novel naturally-occurring allele of eIF4E1.S from the Chinese tobacco landrace Fuquanliuye, designated eIF4E1.Fu, which lacks a genomic region of approximately 27 kb, including the 3'-end of eIF4E1.S. Characterization of the deletion junction enabled the development of a co-dominant PCR-based marker specific for eIF4E1.Fu, which can distinguish eIF4E1.S/eIF4E1.Fu heterozygotes from both homozygous classes. Using this co-dominant marker, we genotyped F2 plants segregating for the mutant eIF4E1.Fu allele and confirmed the correlation between genotype and phenotype. This study describes a novel source of resistance and an ideal co-dominant marker that can be applied in breeding for resistance to PVY and other potyviruses.}, number={7}, journal={EUPHYTICA}, author={Lin, Shifeng and Dewey, Ralph E. and Wang, Rengang and Yu, Jing and Long, Mingjin and Zhang, Jie and Yu, Shizhou and Zhang, Jishun and Wang, Zili and Ren, Xueliang}, year={2021}, month={Jul} }
 @article{lin_dewey_wang_ren_wang_zhang_long_2021, title={Discovery of a novel eIF4E1.S allele conferring PVY resistance in Chinese tobacco (Nicotiana tabacum) landraces}, ISSN={["1439-0523"]}, DOI={10.1111/pbr.12919}, abstractNote={Abstract}, journal={PLANT BREEDING}, author={Lin, Shifeng and Dewey, Ralph E. and Wang, Rengang and Ren, Xueliang and Wang, Zili and Zhang, Jishun and Long, Mingjin}, year={2021}, month={Jun} }
 @article{wu_la hovary_chen_li_eng_vallejo_qu_dewey_2020, title={An Efficient Stevia rebaudiana Transformation System and In vitro Enzyme Assays Reveal Novel Insights into UGT76G1 Function}, volume={10}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-020-60776-y}, abstractNote={Abstract}, number={1}, journal={SCIENTIFIC REPORTS}, author={Wu, Qian and La Hovary, Christophe and Chen, Han-Yi and Li, Xu and Eng, Hayde and Vallejo, Veronica and Qu, Rongda and Dewey, Ralph E.}, year={2020}, month={Feb} }
 @article{lewis_drake-stowe_heim_steede_smith_dewey_2020, title={Genetic and Agronomic Analysis of Tobacco Genotypes Exhibiting Reduced Nicotine Accumulation Due to Induced Mutations in Berberine Bridge Like (BBL) Genes}, volume={11}, ISSN={["1664-462X"]}, DOI={10.3389/fpls.2020.00368}, abstractNote={Genetic methodologies for reducing nicotine accumulation in the tobacco plant (Nicotiana tabacum L.) are of interest because of potential future regulations that could mandate lowering of this alkaloid in conventional cigarettes. Inactivation of tobacco genes such as the Berberine Bridge Like (BBL) gene family believed to encode for enzymes involved in one of the latter steps of nicotine biosynthesis could be a viable strategy for producing new tobacco cultivars with ultra-low leaf nicotine accumulation. We introduced deleterious mutations generated via ethyl methanesulfonate treatment of seed or gene editing into six known members of the BBL gene family and assembled them in different combinations to assess their relative contribution to nicotine accumulation. Significant reductions (up to 17-fold) in percent leaf nicotine were observed in genotypes homozygous for combined mutations in BBL-a, BBL-b, and BBL-c. The addition of mutations in BBL-d1, BBL-d2, and BBL-e had no additional significant effect on lowering of nicotine levels in the genetic background studied. Reduced nicotine levels were associated with reductions in cured leaf yields (up to 29%) and cured leaf quality (up to 15%), evidence of physiological complexities within the tobacco plant related to the nicotine biosynthetic pathway. Further nicotine reductions were observed for a BBL mutant line cultivated under a modified production regime in which apical inflorescences were not removed, but at the expense of further yield reductions. Plants in which BBL mutations were combined with naturally occurring recessive alleles at the Nic1 and Nic2 loci exhibited further reductions in percent nicotine, but no plant produced immeasurable levels of this alkaloid. Findings may suggest the existence of a minor, alternative pathway for nicotine biosynthesis in N. tabacum. The described genetic materials may be of value for the manufacture of cigarettes with reduced nicotine levels and for future studies to better understand the molecular biology of alkaloid accumulation in tobacco.}, journal={FRONTIERS IN PLANT SCIENCE}, author={Lewis, Ramsey S. and Drake-Stowe, Katherine E. and Heim, Crystal and Steede, Tyler and Smith, William and Dewey, Ralph E.}, year={2020}, month={Apr} }
 @article{dluge_song_wang_steede_xiao_liu_dewey_2018, title={Characterization of Nicotiana tabacum genotypes possessing deletion mutations that affect potyvirus resistance and the production of trichome exudates}, volume={19}, ISSN={["1471-2164"]}, DOI={10.1186/s12864-018-4839-y}, abstractNote={Advances in genomics technologies are making it increasingly feasible to characterize breeding lines that carry traits of agronomic interest. Tobacco germplasm lines that carry loci designated VAM and va have been extensively investigated due to their association with potyvirus resistance (both VAM and va) and defects in leaf surface compounds originating from glandular trichomes (VAM only). Molecular studies and classical genetic analyses are consistent with the model that VAM and va represent deletion mutations in the same chromosomal region. In this study, we used RNA-seq analysis, together with emerging tobacco reference genome sequence information to characterize the genomic regions deleted in tobacco lines containing VAM and va. Tobacco genotypes TI 1406 (VAM), K326-va and K326 (wild type) were analyzed using RNA-seq to generate a list of genes differentially expressed in TI 1406 and K326-va, versus the K326 control. Candidate genes were localized onto tobacco genome scaffolds and validated as being absent in only VAM, or missing in both VAM and va, through PCR analysis. These results enabled the construction of a map that predicted the relative extent of the VAM and va mutations on the distal end of chromosome 21. The RNA-seq analyses lead to the discovery that members of the cembratrienol synthase gene family are deleted in TI 1406. Transformation of TI 1406 with a cembratrienol synthase cDNA, however, did not recover the leaf chemistry phenotype. Common to both TI 1406 and K326-va was the absence of a gene encoding a specific isoform of a eukaryotic translation initiation factor (eiF4E1.S). Transformation experiments showed that ectopic expression of eiF4E1.S is sufficient to restore potyvirus susceptibility in plants possessing either the va or VAM mutant loci. We have demonstrated the feasibility of using RNA-seq and emerging whole genome sequence resources in tobacco to characterize the VAM and va deletion mutants. These results lead to the discovery of genes underlying some of the phenotypic traits associated with these historically important loci. Additionally, initial size estimations were made for the deleted regions, and dominant markers were developed that are very close to one of the deletion junctions that defines va.}, journal={BMC GENOMICS}, author={Dluge, Kurtis L. and Song, Zhongbang and Wang, Bingwu and Steede, W. Tyler and Xiao, Bingguang and Liu, Yong and Dewey, Ralph E.}, year={2018}, month={Jun} }
 @article{lu_zhang_lewis_bovet_goepfert_jack_crutchfield_ji_dewey_2016, title={Expression of a constitutively active nitrate reductase variant in tobacco reduces tobacco-specific nitrosamine accumulation in cured leaves and cigarette smoke}, volume={14}, ISSN={["1467-7652"]}, DOI={10.1111/pbi.12510}, abstractNote={Summary}, number={7}, journal={PLANT BIOTECHNOLOGY JOURNAL}, author={Lu, Jianli and Zhang, Leichen and Lewis, Ramsey S. and Bovet, Lucien and Goepfert, Simon and Jack, Anne M. and Crutchfield, James D. and Ji, Huihua and Dewey, Ralph E.}, year={2016}, month={Jul}, pages={1500–1510} }
 @article{patel_milla-lewis_zhang_templeton_reynolds_richardson_biswas_zuleta_dewey_qu_et al._2015, title={Overexpression of ubiquitin-like LpHUB1 gene confers drought tolerance in perennial ryegrass}, volume={13}, ISSN={["1467-7652"]}, DOI={10.1111/pbi.12291}, abstractNote={Summary}, number={5}, journal={PLANT BIOTECHNOLOGY JOURNAL}, publisher={Wiley-Blackwell}, author={Patel, Minesh and Milla-Lewis, Susana and Zhang, Wanjun and Templeton, Kerry and Reynolds, William C. and Richardson, Kim and Biswas, Margaret and Zuleta, Maria C. and Dewey, Ralph E. and Qu, Rongda and et al.}, year={2015}, month={Jun}, pages={689–699} }
 @article{lewis_lopez_bowen_andres_steede_dewey_2015, title={Transgenic and Mutation-Based Suppression of a Berberine Bridge Enzyme-Like (BBL) Gene Family Reduces Alkaloid Content in Field-Grown Tobacco}, volume={10}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0117273}, abstractNote={Motivation exists to develop tobacco cultivars with reduced nicotine content for the purpose of facilitating compliance with expected tobacco product regulations that could mandate the lowering of nicotine levels per se, or the reduction of carcinogenic alkaloid-derived tobacco specific nitrosamines (TSNAs). A berberine bridge enzyme-like (BBL) gene family was recently characterized for N. tabacum and found to catalyze one of the final steps in pyridine alkaloid synthesis for this species. Because this gene family acts downstream in the nicotine biosynthetic pathway, it may represent an attractive target for genetic strategies with the objective of reducing alkaloid content in field-grown tobacco. In this research, we produced transgenic doubled haploid lines of tobacco cultivar K326 carrying an RNAi construct designed to reduce expression of the BBL gene family. Field-grown transgenic lines carrying functional RNAi constructs exhibited average cured leaf nicotine levels of 0.684%, in comparison to 2.454% for the untransformed control. Since numerous barriers would need to be overcome to commercialize transgenic tobacco cultivars, we subsequently pursued a mutation breeding approach to identify EMS-induced mutations in the three most highly expressed isoforms of the BBL gene family. Field evaluation of individuals possessing different homozygous combinations of truncation mutations in BBLa, BBLb, and BBLc indicated that a range of alkaloid phenotypes could be produced, with the triple homozygous knockout genotype exhibiting greater than a 13-fold reduction in percent total alkaloids. The novel source of genetic variability described here may be useful in future tobacco breeding for varied alkaloid levels.}, number={2}, journal={PLOS ONE}, author={Lewis, Ramsey S. and Lopez, Harry O. and Bowen, Steve W. and Andres, Karen R. and Steede, William T. and Dewey, Ralph E.}, year={2015}, month={Feb} }
 @article{cardinal_whetten_wang_auclair_hyten_cregan_bachlava_gillman_ramirez_dewey_et al._2014, title={Mapping the low palmitate fap1 mutation and validation of its effects in soybean oil and agronomic traits in three soybean populations}, volume={127}, ISSN={["1432-2242"]}, DOI={10.1007/s00122-013-2204-8}, abstractNote={fap 1 mutation is caused by a G174A change in GmKASIIIA that disrupts a donor splice site recognition and creates a GATCTG motif that enhanced its expression. Soybean oil with reduced palmitic acid content is desirable to reduce the health risks associated with consumption of this fatty acid. The objectives of this study were: to identify the genomic location of the reduced palmitate fap1 mutation, determine its molecular basis, estimate the amount of phenotypic variation in fatty acid composition explained by this locus, determine if there are epistatic interactions between the fap1 and fap nc loci and, determine if the fap1 mutation has pleiotropic effects on seed yield, oil and protein content in three soybean populations. This study detected two major QTL for 16:0 content located in chromosome 5 (GmFATB1a, fap nc) and chromosome 9 near BARCSOYSSR_09_1707 that explained, with their interaction, 66–94 % of the variation in 16:0 content in the three populations. Sequencing results of a putative candidate gene, GmKASIIIA, revealed a single unique polymorphism in the germplasm line C1726, which was predicted to disrupt the donor splice site recognition between exon one and intron one and produce a truncated KASIIIA protein. This G to A change also created the GATCTG motif that enhanced gene expression of the mutated GmKASIIIA gene. Lines homozygous for the GmKASIIIA mutation (fap1) had a significant reduction in 16:0, 18:0, and oil content; and an increase in unsaturated fatty acids content. There were significant epistatic interactions between GmKASIIIA (fap1) and fap nc for 16:0 and oil contents, and seed yield in two populations. In conclusion, the fap1 phenotype is caused by a single unique SNP in the GmKASIIIA gene.}, number={1}, journal={THEORETICAL AND APPLIED GENETICS}, author={Cardinal, Andrea J. and Whetten, Rebecca and Wang, Sanbao and Auclair, Jerome and Hyten, David and Cregan, Perry and Bachlava, Eleni and Gillman, Jason and Ramirez, Martha and Dewey, Ralph and et al.}, year={2014}, month={Jan}, pages={97–111} }
 @article{cai_jack_lewis_dewey_bush_2013, title={(R)-nicotine biosynthesis, metabolism and translocation in tobacco as determined by nicotine demethylase mutants}, volume={95}, ISSN={["0031-9422"]}, DOI={10.1016/j.phytochem.2013.06.012}, abstractNote={Nicotine is a chiral compound and consequently exists as two enantiomers. Since (R)-nicotine consists of less than 0.5% of total nicotine pool in tobacco, few investigations relating to (R)-nicotine have been reported. However, previous studies of nicotine demethylases suggested there was substantial amount of (R)-nicotine at synthesis in the tobacco plant. In this study, the accumulation and translocation of (R)-nicotine in tobacco was analyzed. The accumulation of nicotine and its demethylation product the nornicotine enantiomers, were investigated in different tobacco plant parts and at different growth and post-harvest stages. Scion/rootstock grafts were used to separate the contributions of roots (source) from leaves (sink) to the final accumulation of nicotine and nornicotine in leaf tissue. The results indicate that 4% of nicotine is in the (R) form at synthesis in the root. After the majority of (R)-nicotine is selectively demethylated by CYP82E4, CYP82E5v2 and CYP82E10 in the root, nicotine and nornicotine are translocated to leaf, where more nicotine becomes demethylated. Depending on the CYP82E4 activity in senescing leaf, constant low (R)-nicotine remains in the tobacco leaf and variable nornicotine composition is produced. These results confirmed the enantioselectivity of three nicotine demethylases in planta, could be used to predict the changes of nicotine and nornicotine composition, and may facilitate demethylase discovery in the future.}, journal={PHYTOCHEMISTRY}, author={Cai, Bin and Jack, Anne M. and Lewis, Ramsey S. and Dewey, Ralph E. and Bush, Lowell P.}, year={2013}, month={Nov}, pages={188–196} }
 @article{zhang_dewey_boss_phillippy_qu_2013, title={Enhanced Agrobacterium-mediated transformation efficiencies in monocot cells is associated with attenuated defense responses}, volume={81}, ISSN={["1573-5028"]}, DOI={10.1007/s11103-012-9997-8}, abstractNote={Plant defense responses can lead to altered metabolism and even cell death at the sites of Agrobacterium infection, and thus lower transformation frequencies. In this report, we demonstrate that the utilization of culture conditions associated with an attenuation of defense responses in monocot plant cells led to highly improved Agrobacterium-mediated transformation efficiencies in perennial ryegrass (Lolium perenne L.). The removal of myo-inositol from the callus culture media in combination with a cold shock pretreatment and the addition of L-Gln prior to and during Agrobacterium-infection resulted in about 84 % of the treated calluses being stably transformed. The omission of myo-inositol from the callus culture media was associated with the failure of certain pathogenesis related genes to be induced after Agrobacterium infection. The addition of a cold shock and supplemental Gln appeared to have synergistic effects on infection and transformation efficiencies. Nearly 60 % of the stably transformed calluses regenerated into green plantlets. Calluses cultured on media lacking myo-inositol also displayed profound physiological and biochemical changes compared to ones cultured on standard growth media, such as reduced lignin within the cell walls, increased starch and inositol hexaphosphate accumulation, enhanced Agrobacterium binding to the cell surface, and less H(2)O(2) production after Agrobacterium infection. Furthermore, the cold treatment greatly reduced callus browning after infection. The simple modifications described in this report may have broad application for improving genetic transformation of recalcitrant monocot species.}, number={3}, journal={PLANT MOLECULAR BIOLOGY}, author={Zhang, Wan-Jun and Dewey, Ralph E. and Boss, Wendy and Phillippy, Brian Q. and Qu, Rongda}, year={2013}, month={Feb}, pages={273–286} }
 @article{patel_dewey_qu_2013, title={Enhancing Agrobacterium tumefaciens-mediated transformation efficiency of perennial ryegrass and rice using heat and high maltose treatments during bacterial infection}, volume={114}, ISSN={["1573-5044"]}, DOI={10.1007/s11240-013-0301-7}, number={1}, journal={PLANT CELL TISSUE AND ORGAN CULTURE}, author={Patel, Minesh and Dewey, Ralph E. and Qu, Rongda}, year={2013}, month={Jul}, pages={19–29} }
 @misc{dewey_xie_2013, title={Molecular genetics of alkaloid biosynthesis in Nicotiana tabacum}, volume={94}, ISSN={["1873-3700"]}, DOI={10.1016/j.phytochem.2013.06.002}, abstractNote={Alkaloids represent an extensive group of nitrogen-containing secondary metabolites that are widely distributed throughout the plant kingdom. The pyridine alkaloids of tobacco (Nicotiana tabacum L.) have been the subject of particularly intensive investigation, driven largely due to the widespread use of tobacco products by society and the role that nicotine (16) (see Fig. 1) plays as the primary compound responsible for making the consumption of these products both pleasurable and addictive. In a typical commercial tobacco plant, nicotine (16) comprises about 90% of the total alkaloid pool, with the alkaloids nornicotine (17) (a demethylated derivative of nicotine), anatabine (15) and anabasine (5) making up most of the remainder. Advances in molecular biology have led to the characterization of the majority of the genes encoding the enzymes directly responsible the biosynthesis of nicotine (16) and nornicotine (17), while notable gaps remain within the anatabine (15) and anabasine (5) biosynthetic pathways. Several of the genes involved in the transcriptional regulation and transport of nicotine (16) have also been elucidated. Investigations of the molecular genetics of tobacco alkaloids have not only provided plant biologists with insights into the mechanisms underlying the synthesis and accumulation of this important class of plant alkaloids, they have also yielded tools and strategies for modifying the tobacco alkaloid composition in a manner that can result in changing the levels of nicotine (16) within the leaf, or reducing the levels of a potent carcinogenic tobacco-specific nitrosamine (TSNA). This review summarizes recent advances in our understanding of the molecular genetics of alkaloid biosynthesis in tobacco, and discusses the potential for applying information accrued from these studies toward efforts designed to help mitigate some of the negative health consequences associated with the use of tobacco products.}, journal={PHYTOCHEMISTRY}, author={Dewey, Ralph E. and Xie, Jiahua}, year={2013}, month={Oct}, pages={10–27} }
 @article{li_lewis_jack_dewey_bowen_miller_2012, title={Development of CAPS and dCAPS markers for CYP82E4, CYP82E5v2 and CYP82E10 gene mutants reducing nicotine to nornicotine conversion in tobacco}, volume={29}, ISSN={["1572-9788"]}, DOI={10.1007/s11032-011-9575-9}, number={3}, journal={MOLECULAR BREEDING}, author={Li, Dandan and Lewis, Ramsey S. and Jack, Anne M. and Dewey, Ralph E. and Bowen, Steve W. and Miller, Robert D.}, year={2012}, month={Mar}, pages={589–599} }
 @article{cai_siminszky_chappell_dewey_bush_2012, title={Enantioselective Demethylation of Nicotine as a Mechanism for Variable Nornicotine Composition in Tobacco Leaf}, volume={287}, ISSN={["1083-351X"]}, DOI={10.1074/jbc.m112.413807}, abstractNote={Background: Nornicotine composition in tobacco leaf has been a puzzle for more than half a century. Results: Three recombinant nicotine demethylases selectively use (R)-nicotine in vitro and in planta. Conclusion: Nornicotine composition in tobacco leaf can be reasonably explained by the combination of three nicotine demethylases. Significance: This knowledge lays the base for the optimization of nornicotine composition in tobacco leaf in the future. Nicotine and its N-demethylation product nornicotine are two important alkaloids in Nicotiana tabacum L. (tobacco). Both nicotine and nornicotine have two stereoisomers that differ from each other at 2′-C position on the pyrrolidine ring. (S)-Nicotine is the predominant form in the tobacco leaf, whereas the (R)-enantiomer only accounts for ∼0.2% of the total nicotine pool. Despite considerable past efforts, a comprehensive understanding of the factors responsible for generating an elevated and variable enantiomer fraction of nornicotine (EFnnic of 0.04 to 0.75) from the consistently low EF observed for nicotine has been lacking. The objective of this study was to determine potential roles of enantioselective demethylation in the formation of the nornicotine EF. Recombinant CYP82E4, CYP82E5v2, and CYP82E10, three known tobacco nicotine demethylases, were expressed in yeast and assayed for their enantioselectivities in vitro. Recombinant CYP82E4, CYP82E5v2, and CYP82E10 demethylated (R)-nicotine 3-, 10-, and 10-fold faster than (S)-nicotine, respectively. The combined enantioselective properties of the three nicotine demethylases can reasonably account for the nornicotine composition observed in tobacco leaves, which was confirmed in planta. Collectively, our studies suggest that an enantioselective mechanism facilitates the maintenance of a reduced (R)-nicotine pool and, depending on the relative abundances of the three nicotine demethylase enzymes, can confer a high (R)-enantiomer percentage within the nornicotine fraction of the leaf.}, number={51}, journal={JOURNAL OF BIOLOGICAL CHEMISTRY}, author={Cai, Bin and Siminszky, Balazs and Chappell, Joseph and Dewey, Ralph E. and Bush, Lowell P.}, year={2012}, month={Dec}, pages={42804–42811} }
 @article{cardinal_burton_camacho-roger_whetten_chappell_bilyeu_auclair_dewey_2011, title={Molecular Analysis of GmFAD3A in Two Soybean Populations Segregating for the fan, fap1, and fap(nc) Loci}, volume={51}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2010.08.0500}, abstractNote={Soybeans [Glycine max (L.) Merr.] have undesirable levels of polyunsaturated fatty acids in their oil that result in oxidative instability and poor flavor. The process of hydrogenation improves the stability but creates undesirable trans fats. Lines carrying fan genes have decreased linolenic acid (18:3) content. Changes in transcription or activity of the desaturase encoded by the GmFAD3 gene cause a reduction in 18:3 content in certain lines. The objectives of this study were to determine the molecular basis of the fan allele in PI 123440, develop molecular markers to assay for the GmFAD3 gene in lines carrying fan(PI 123440), and estimate the variation in the 18:3 explained by the GmFAD3A locus. Sequence analysis of the GmFAD3A from ‘Soyola’, the fan(PI 123440) allele, and ‘Dare’ showed no sequence polymorphisms that would alter the amino acid sequence of the enzyme. RNA blot analysis of a low‐18:3 line carrying a fan(PI 123440) allele, a line with normal 18:3 content, and three of their progenies showed a decrease in steady‐state FAD3A RNA levels in low‐18:3 lines. A marker for GmFAD3A was tested in two populations segregating for fan(PI 123440). Lines homozygous the GmFAD3A allele inherited from PI 123440 had a significant reduction in 18:3 when compared to lines homozygous for the GmFAD3A allele from the normal 18:3 parent. The differences between the two groups explained more than 77.5% of the genetic variation in 18:3 seed‐oil content in the populations. In summary, a reduction in the steady‐state mRNA levels of the GmFAD3A leads to a reduction in 18:3 synthesis within the developing seed in plants containing the fan(PI 123440) allele.}, number={5}, journal={CROP SCIENCE}, author={Cardinal, Andrea J. and Burton, Joseph W. and Camacho-Roger, Ana Maria and Whetten, Rebecca and Chappell, Andrew S. and Bilyeu, Kristin D. and Auclair, Jerome and Dewey, Ralph E.}, year={2011}, month={Sep}, pages={2104–2112} }
 @article{de vries_fehr_welke_dewey_2011, title={Molecular Analysis of Mutant Alleles for Elevated Palmitate Concentration in Soybean}, volume={51}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2011.03.0156}, abstractNote={ABSTRACT}, number={6}, journal={CROP SCIENCE}, author={De Vries, Brian D. and Fehr, Walter R. and Welke, Grace A. and Dewey, Ralph E.}, year={2011}, month={Nov}, pages={2554–2560} }
 @article{de vries_fehr_welke_dewey_2011, title={Molecular Characterization of the Mutant fap3(A22) Allele for Reduced Palmitate Concentration in Soybean}, volume={51}, ISSN={["0011-183X"]}, DOI={10.2135/cropsci2010.10.0619}, abstractNote={ABSTRACTReduction of the palmitate concentration in soybean [Glycine max (L.) Merr.] oil is desirable for reducing the amount of saturated fat in the human diet. Chemical mutagenesis was used to develop the line A22 with the mutant allele designated fap3(A22) that reduces palmitate concentration in the seed oil. The objective of our study was to determine the molecular basis of the fap3(A22) mutation and develop a corresponding molecular marker to assist in future efforts for developing soybean cultivars with low saturated fat. DNA sequence analysis of the GmFATB1a gene of soybean revealed a single nucleotide polymorphism (SNP) resulting in a nonconservative amino acid substitution that was likely to be detrimental to the function of the 16:0–acyl carrier protein (ACP) thioesterase (TE) enzyme. An association analysis was conducted using F2–derived lines from a cross between the cultivar Archer (Fap3Fap3) and A22 (fap3fap3) that had been analyzed for their palmitate concentration by gas chromatography. Molecular genotyping of these lines established a perfect correlation between lines phenotypically classified as homozygous for the Fap3 allele or homozygous for the fap3(A22) allele based on their palmitate concentration. The polymorphism in the GmFATB1a gene was used to develop a functional, codominant marker that could be used to distinguish the Fap3 and fap3(A22) alleles in segregating populations. This marker will be useful for breeders who are developing low‐saturate cultivars with the fap3(A22) allele.}, number={4}, journal={CROP SCIENCE}, author={De Vries, Brian D. and Fehr, Walter R. and Welke, Grace A. and Dewey, Ralph E.}, year={2011}, month={Jul}, pages={1611–1616} }
 @article{lewis_bowen_keogh_dewey_2010, title={Three nicotine demethylase genes mediate nornicotine biosynthesis in Nicotiana tabacum L Functional characterization of the CYP82E10 gene}, volume={71}, ISSN={["1873-3700"]}, DOI={10.1016/j.phytochem.2010.09.011}, abstractNote={In most tobacco (Nicotiana tabacum L.) plants, nornicotine is a relatively minor alkaloid, comprising about 2–5% of the total pyridine alkaloid pool in the mature leaf. Changes in gene expression at an unstable locus, however, can give rise to plants that produce high levels of nornicotine, specifically during leaf senescence and curing. Minimizing the nornicotine content in tobacco is highly desirable, because this compound serves as the direct precursor in the synthesis of N′-nitrosonornicotine, a potent carcinogen in laboratory animals. Nornicotine is likely produced almost entirely via the N-demethylation of nicotine, in a process called nicotine conversion that is catalyzed by the enzyme nicotine N-demethylase (NND). Previous studies have identified CYP82E4 as the specific NND gene responsible for the unstable conversion phenomenon, and CYP82E5v2 as a putative minor NND gene. Here, by discovery and characterization of CYP82E10, a tobacco NND gene, is reported. PCR amplification studies showed that CYP82E10 originated from the N. sylvestris ancestral parent of modern tobacco. Using a chemical mutagenesis strategy, knockout mutations were induced and identified in all three tobacco NND genes. By generating a series of mutant NND genotypes, the relative contribution of each NND gene toward the nornicotine content of the plant was assessed. Plants possessing knockout mutations in all three genes displayed nornicotine phenotypes that were much lower (∼0.5% of total alkaloid content) than that found in conventional tobacco cultivars. The introduction of these mutations into commercial breeding lines promises to be a viable strategy for reducing the levels of one of the best characterized animal carcinogens found in tobacco products.}, number={17-18}, journal={PHYTOCHEMISTRY}, author={Lewis, Ramsey S. and Bowen, Steven W. and Keogh, Matthew R. and Dewey, Ralph E.}, year={2010}, month={Dec}, pages={1988–1998} }
 @article{keogh_courtney_kinney_dewey_2009, title={Functional Characterization of Phospholipid N-Methyltransferases from Arabidopsis and Soybean}, volume={284}, ISSN={["1083-351X"]}, DOI={10.1074/jbc.M109.005991}, abstractNote={Phospholipid N-methyltransferase (PLMT) enzymes catalyze the S-adenosylmethionine-dependent methylation of ethanolamine-containing phospholipids to produce the abundant membrane lipid phosphatidylcholine (PtdCho). In mammals and yeast, PLMT activities are required for the de novo synthesis of the choline headgroup found in PtdCho. PLMT enzyme activities have also been reported in plants, yet their roles in PtdCho biosynthesis are less clear because most plants can produce the choline headgroup entirely via soluble substrates, initiated by the methylation of free ethanolamine-phosphate. To gain further insights into the function of PLMT enzymes in plants, we isolated PLMT cDNAs from Arabidopsis and soybean (Glycine max) based upon primary amino acid sequence homology to the rat PLMT, phosphatidylethanolamine N-methyltransferase. Using a heterologous yeast expression system, it was shown that plant PLMTs methylate phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine but cannot utilize phosphatidylethanolamine as a substrate. Identification of an Arabidopsis line containing a knock-out dissociator transposon insertion within the single copy AtPLMT gene allowed us to investigate the consequences of loss of PLMT function. Although the accumulation of the PLMT substrates phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine was considerably elevated in the atplmt knock-out line, PtdCho levels remained normal, and no obvious differences were observed in plant morphology or development under standard growth conditions. However, because the metabolic routes through which PtdCho is synthesized in plants vary greatly among differing species, it is predicted that the degree with which PtdCho synthesis is dependent upon PLMT activities will also vary widely throughout the plant kingdom.}, number={23}, journal={JOURNAL OF BIOLOGICAL CHEMISTRY}, author={Keogh, Matthew R. and Courtney, Polly D. and Kinney, Anthony J. and Dewey, Ralph E.}, year={2009}, month={Jun}, pages={15439–15447} }
 @article{bachlava_dewey_burton_cardinal_2009, title={Mapping and Comparison of Quantitative Trait Loci for Oleic Acid Seed Content in Two Segregating Soybean Populations}, volume={49}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2008.06.0324}, abstractNote={Soybean [Glycine max (L.) Merr.] produces 29.4% of the world's edible vegetable oil. An important determinant of the nutritional value and the oxidative stability of soybean oil is the oleic acid content. Elevation of the oleate content levels leads to the improvement of soybean oil quality. However, our knowledge of the genetic factors underlying oleate variation in soybean seeds remains incomplete, hampering the use of marker‐assisted selection in soybean breeding programs. We used a whole‐genome scan approach to identify oleate quantitative trait loci (QTLs) in a soybean population segregating for oleic acid content and a cognate segregating population to confirm oleate QTL. A novel oleate QTL with moderate effects was revealed on linkage group F in the proximity of the simple sequence repeat marker sat_309, which was confirmed in both populations across all environments tested. Furthermore, this study verified the existence of an oleate QTL with moderate effects in the proximity of FAD2‐1B isoform on linkage group I, which interacted epistatically with the oleate QTL on linkage group F. Oleate QTLs with moderate effects were also detected on linkage groups A2 and N only in one of the populations under study. Minor QTLs on linkage groups E, L, A1, and D2 confirmed previous mapping studies for oleate content in soybean.}, number={2}, journal={CROP SCIENCE}, author={Bachlava, Eleni and Dewey, Ralph E. and Burton, Joseph W. and Cardinal, Andrea J.}, year={2009}, pages={433–442} }
 @article{bachlava_dewey_burton_cardinal_2009, title={Mapping candidate genes for oleate biosynthesis and their association with unsaturated fatty acid seed content in soybean}, volume={23}, ISSN={["1572-9788"]}, DOI={10.1007/s11032-008-9246-7}, number={2}, journal={MOLECULAR BREEDING}, author={Bachlava, Eleni and Dewey, Ralph E. and Burton, Joseph W. and Cardinal, Andrea J.}, year={2009}, month={Feb}, pages={337–347} }
 @article{chakrabarti_bowen_coleman_meekins_dewey_siminszky_2008, title={CYP82E4-mediated nicotine to nornicotine conversion in tobacco is regulated by a senescence-specific signaling pathway}, volume={66}, ISSN={["1573-5028"]}, DOI={10.1007/s11103-007-9280-6}, abstractNote={Nicotine to nornicotine conversion in tobacco (Nicotiana tabacum L.) is regulated by an unstable converter locus which in its activated state gives rise to a high nornicotine, low nicotine phenotype in the senescing leaves. In plants that carry the high nornicotine trait, nicotine conversion is primarily catalyzed by a cytochrome P450 protein, designated CYP82E4 whose transcription is strongly upregulated during leaf senescence. To further investigate the regulation of CYP82E4 expression, we examined the spatiotemporal distribution and the stress- and signaling molecule-elicited expression patterns of CYP82E4 using alkaloid analysis and a fusion construct between the 2.2 kb upstream regulatory region of CYP82E4 and the beta-glucurodinase (GUS) gene. Histochemical and fluorometric analyses of GUS expression revealed that the CYP82E4 promoter confers high levels of expression in the senescing leaves and flowers, and in the green stems of young and mature plants, but only very low activity was detected in the roots. In the leaves, GUS activity was strongly correlated with the progression of senescence. Treatments of leaf tissue with various signaling molecules including abscisic acid, ethylene, jasmonic acid, salicylic acid and yeast extract; and stresses, such as drought, wounding and tobacco mosaic virus infection did not enhance nicotine conversion or GUS activity in the green leaves, but an increase in CYP82E4 expression was observed in response to ethylene- or tobacco mosaic virus-induced senescence. These results suggest that the expression of CYP82E4 is senescence-specific in the leaves and the use of the CYP82E4 promoter could provide a valuable tool for regulating gene expression in the senescing leaves.}, number={4}, journal={PLANT MOLECULAR BIOLOGY}, author={Chakrabarti, Manohar and Bowen, Steven W. and Coleman, Nicholas P. and Meekins, Karen M. and Dewey, Ralph E. and Siminszky, Balazs}, year={2008}, month={Mar}, pages={415–427} }
 @article{cardinal_dewey_burton_2008, title={Estimating the individual effects of the reduced palmitic acid fap(nc) and fap1 alleles on agronomic traits in two soybean populations}, volume={48}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2007.05.0251}, abstractNote={Major fap alleles that reduce palmitate content in soybean [Glycine max (L.) Merr.] seed oil also can reduce seed yield. One of these alleles, fapnc, has been shown to be a deletion in the GmFATB1a gene. Allele‐specific primers that amplify GmFATB1a can be used to test precisely if the fapnc allele has an effect on agronomic traits. The objectives of this study were to determine if the segregation of the fapnc allele explained a significant amount of genetic variation in several agronomic traits; to determine if the fap1 allele or minor palmitate genes have an effect on agronomic traits; and to confirm if GmFATB1a maps to the distal region on linkage group A1. GmFATB1a‐specific primers were used to genotype lines from two populations segregating for fapnc, fap1, and fan alleles and modifier genes. The fapnc allele explained a significant portion of the genetic variation in seed yield, plant height, protein content, and stearic acid content in both populations. After removing the effect of fapnc from the model, the genetic correlation between palmitate and yield was significant in one population but not significant between palmitate and height, indicating that fap1 has a small but significant effect on seed yield but no effect on plant height. The fap1 and/or modifier genes significantly affected stearic acid content. GmFATB1a mapped 20 cM distal to Satt684 on linkage group A1. Breeding efforts did not totally eliminate the negative influence of the fapnc allele on seed yield and plant height.}, number={2}, journal={CROP SCIENCE}, author={Cardinal, Andrea J. and Dewey, Ralph E. and Burton, Joseph W.}, year={2008}, pages={633–639} }
 @article{bachlava_dewey_auclair_wang_burton_cardinal_2008, title={Mapping genes encoding microsomal omega-6 desaturase enzymes and their cosegregation with QTL affecting oleate content in soybean}, volume={48}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2007.07.0381}, abstractNote={The microsomal ω‐6 desaturase enzymes, which catalyze the desaturation of oleic acid to linoleic acid during fatty acid biosynthesis, are encoded by the FAD2‐1 and FAD2‐2 genes in soybean [Glycine max (L.) Merr.]. Breeders aim to incorporate the high‐oleate trait into soybean germplasm in order to improve the nutritional value and oxidative stability of soybean oil. The objectives of this study were to map the isoforms of the FAD2‐1 and FAD2‐2 genes and investigate the association of these genetic loci with the oleate phenotype in three populations segregating for oleate content. The populations were grown in replicated multienvironment field trials. According to linkage analysis conducted for two of the populations, FAD2‐1A and FAD2‐1B mapped on Linkage Groups O and I, respectively, while the closely linked FAD2‐2A and FAD2‐2B isoforms mapped on Linkage Group L. Oleate quantitative trait loci with minor effects were detected in the proximity of FAD2‐1B and possibly FAD2‐2B on Linkage Groups I and L. Quantitative trait loci affecting maturity were also detected on chromosomal regions adjacent to the FAD2 genes. The genotyping assays developed for the FAD2‐1A, FAD2‐1B, and FAD2‐2B isoforms, as well as their linked simple sequence repeat markers, can be used in soybean breeding programs for the elevation of oleic acid seed content through marker‐assisted selection.}, number={2}, journal={CROP SCIENCE}, author={Bachlava, Eleni and Dewey, Ralph E. and Auclair, Jerome and Wang, Sanbao and Burton, Joseph W. and Cardinal, Andrea J.}, year={2008}, pages={640–650} }
 @article{zhang_burton_upchurch_whittle_shanklin_dewey_2008, title={Mutations in a Delta(9)-Stearoyl-ACP-Desaturase Gene Are Associated with Enhanced Stearic Acid Levels in Soybean Seeds}, volume={48}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2008.02.0084}, abstractNote={Stearic acid (18:0) is typically a minor component of soybean [Glycine max (L.) Merr.] oil, accounting for only 2 to 4% of the total fatty acid content. Increasing stearic acid levels of soybean oil would lead to enhanced oxidative stability, potentially reducing the need for hydrogenation, a process leading to the formation of undesirable trans fatty acids. Although mutagenesis strategies have been successful in developing soybean germplasm with elevated 18:0 levels in the seed oil, the specific gene mutations responsible for this phenotype were not known. We report a newly identified soybean gene, designated SACPD‐C, that encodes a unique isoform of Δ9–stearoyl‐ACP‐desaturase, the enzyme responsible for converting stearic acid to oleic acid (18:1). High levels of SACPD‐C transcript were only detected in developing seed tissue, suggesting that the encoded desaturase functions to enhance oleic acid biosynthetic capacity as the immature seed is actively engaged in triacylglycerol production and storage. The participation of SACPD‐C in storage triacylglycerol synthesis is further supported by the observation of mutations in this gene in two independent sources of elevated 18:0 soybean germplasm, A6 (30% 18:0) and FAM94‐41 (9% 18:0). A molecular marker diagnostic for the FAM94‐41 SACPD‐C gene mutation strictly associates with the elevated 18:0 phenotype in a segregating population, and could thus serve as a useful tool in the development of cultivars with oils possessing enhanced oxidative stability.}, number={6}, journal={CROP SCIENCE}, author={Zhang, Ping and Burton, Joseph W. and Upchurch, Robert G. and Whittle, Edward and Shanklin, John and Dewey, Ralph E.}, year={2008}, pages={2305–2313} }
 @article{lewis_jack_morris_robert_gavilano_siminszky_bush_hayes_dewey_2008, title={RNA interference (RNAi)-induced suppression of nicotine demethylase activity reduces levels of a key carcinogen in cured tobacco leaves}, volume={6}, ISSN={["1467-7644"]}, DOI={10.1111/j.1467-7652.2008.00324.x}, abstractNote={Summary}, number={4}, journal={PLANT BIOTECHNOLOGY JOURNAL}, author={Lewis, Ramsey S. and Jack, Anne M. and Morris, Jerry W. and Robert, Vincent J. M. and Gavilano, Lily B. and Siminszky, Balazs and Bush, Lowell P. and Hayes, Alec J. and Dewey, Ralph E.}, year={2008}, month={May}, pages={346–354} }
 @article{irsigler_costa_zhang_reis_dewey_boston_fontes_2007, title={Expression profiling on soybean leaves reveals integration of ER- and osmotic-stress pathways}, volume={8}, ISSN={["1471-2164"]}, DOI={10.1186/1471-2164-8-431}, abstractNote={Abstract}, journal={BMC GENOMICS}, author={Irsigler, Andre ST and Costa, Maximiller Dl and Zhang, Ping and Reis, Pedro AB and Dewey, Ralph E. and Boston, Rebecca S. and Fontes, Elizabeth P. B.}, year={2007}, month={Nov} }
 @article{cardinal_burton_camacho-roger_yang_wilson_dewey_2007, title={Molecular analysis of soybean lines with low palmitic acid content in the seed oil}, volume={47}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2006.04.0272}, abstractNote={ABSTRACTPalmitic acid is the major saturated fatty acid found in soybean [Glycine max (L.) Merr.] oil, accounting for approximately 11% of the seed oil content. Reducing the palmitic acid levels of the oil is desirable because of the negative health effects specifically associated with this fatty acid. One of the genetic loci known to reduce the seed palmitate content in soybean is fapnc. Previous studies indicated that fapnc is associated with a deletion in a gene (designated FATB) encoding 16:0‐ACP thioesterase activity. In this report, we isolated full length cDNAs of three of the four unique FATB genes expressed in soybean and show that the isoform designated GmFATB1a represents the specific gene deleted in lines possessing the fapnc locus. Allele specific primers corresponding to GmFATB1a were used to genotype plants from two F4‐derived populations that were segregating for fapnc The GmFATB1a‐specific markers were effective in accounting for 62 to 70% of the genotypic variation in palmitate content in the two populations studied. Because the markers developed in this study are 100% linked to the locus of interest, they should be particularly useful in marker‐assisted selection programs designed to lower the palmitic acid levels of soybean oil.}, number={1}, journal={CROP SCIENCE}, author={Cardinal, Andrea J. and Burton, Joseph W. and Camacho-Roger, Ana Maria and Yang, Ji H. and Wilson, Richard F. and Dewey, Ralph E.}, year={2007}, pages={304–310} }
 @article{aghoram_wilson_burton_dewey_2006, title={A mutation in a 3-keto-acyl-ACP synthase II gene is associated with elevated palmitic acid levels in soybean seeds}, volume={46}, ISSN={["1435-0653"]}, DOI={10.2135/cropsci2006.04.0218}, abstractNote={Palmitic acid is the major saturated fatty acid component of soybean [Glycine max (L.) Merr.] oil, typically accounting for approximately 11% of total seed oil content. Several genetic loci have been shown to control the seed palmitate content of soybean. One such locus, fap2, mediates an elevated seed palmitate phenotype. Previous biochemical studies indicated that the fap2 locus is associated with a reduction in the activity of 3‐keto‐acyl‐ACP synthase II (KAS II), an enzyme that initiates the elongation of palmitoyl‐ACP to stearoyl‐ACP in the plastid. The objective of the present research was to define the molecular basis by which the fap2 locus increases seed palmitate levels. We isolated two closely related, yet unique KAS II cDNAs, designated GmKAS IIA and GmKAS IIB, from soybean cultivar Century (Fap2, Fap2) and its derivative high palmitate germplasm C1727 (fap2, fap2). The GmKAS IIB cDNAs recovered from Century and C1727 were identical. In contrast, a single base‐pair substitution was found in the GmKAS IIA gene from C1727 versus Century which converted a tryptophan codon into a premature stop codon, a mutation that would be predicted to render the encoded enzyme nonfunctional. Knowledge of the DNA sequence polymorphism led to the development a facile, robust cleavage amplified polymorphic sequence (CAPS) marker that readily distinguishes the mutant GmKAS IIA gene. This marker faithfully associated with a second independent germplasm line bearing the fap2 locus, and thus may be useful in breeding programs that target the development of high palmitate soybean cultivars.}, number={6}, journal={CROP SCIENCE}, author={Aghoram, Karthik and Wilson, Richard E. and Burton, Joseph W. and Dewey, Ralph E.}, year={2006}, pages={2453–2459} }
 @article{siminszky_gavilano_bowen_dewey_2005, title={Conversion of nicotine to nornicotine in Nicotiana tabacum is mediated by CYP82E4, a cytochrome P450 monooxygenase}, volume={102}, DOI={10.1073/pnas.050658102}, number={41}, journal={Proceedings of the National Academy of Sciences of the United States of America}, author={Siminszky, B. and Gavilano, L. and Bowen, S. W. and Dewey, R. E.}, year={2005}, pages={14919–14924} }
 @article{siminszky_gavilano_bowen_dewey_2005, title={Conversion of nicotine to nornicotine in Nicotiana tabacum is mediated by CYP82E4, a cytochrome P450 monooxygenase}, volume={102}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.0506581102}, DOI={10.1073/pnas.0506581102}, abstractNote={
            Nornicotine is a secondary tobacco alkaloid that is produced by the N-demethylation of nicotine. Nornicotine production and accumulation in tobacco are undesirable because nornicotine serves as the precursor in the synthesis of the well characterized carcinogen
            N
            ′-nitrosonornicotine during the curing and processing of tobacco. Although nornicotine is typically a minor alkaloid in tobacco plants, in many tobacco populations a high percentage of individuals can be found that convert a substantial proportion of the nicotine to nornicotine during leaf senescence and curing. We used a microarray-based strategy to identify genes that are differentially regulated between closely related tobacco lines that accumulate either nicotine (nonconverters) or nornicotine (converters) as the predominant alkaloid in the cured leaf. These experiments led to the identification of a small number of closely related cytochrome P450 genes, designated the
            CYP82E2
            family, whose collective transcript levels were consistently higher in converter versus nonconverter tobacco lines. RNA interference-induced silencing of the
            CYP82E2
            gene family suppressed the synthesis of nornicotine in strong converter plants to levels similar to that observed in nonconverter individuals. Although each of the six identified members of the P450 family share >90% nucleotide sequence identity, sense expression of three selected isoforms revealed that only one (
            CYP82E4v1
            ) was involved in the conversion of nicotine to nornicotine. Yeast expression analysis revealed that CYP82E4v1 functions as a nicotine demethylase. Identification of the gene(s) responsible for nicotine demethylation provides a potentially powerful tool toward efforts to minimize nornicotine levels, and thereby
            N
            ′-nitrosonornicotine formation, in tobacco products.
          }, number={41}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Siminszky, B. and Gavilano, L. and Bowen, S. W. and Dewey, R. E.}, year={2005}, month={Sep}, pages={14919–14924} }
 @article{hernandez-sebastia_marsolais_saravitz_israel_dewey_huber_2005, title={Free amino acid profiles suggest a possible role for asparagine in the control of storage-product accumulation in developing seeds of low- and high-protein soybean lines}, volume={56}, ISSN={["1460-2431"]}, DOI={10.1093/jxb/eri191}, abstractNote={Several approaches were taken to examine the role of N-assimilate supply in the control of soybean (Glycine max) seed composition. In the first study, developing seeds were grown in vitro with D-[U-14C]sucrose (Suc) and different concentrations of Gln. Light stimulated carbon flux into oil and protein, and was required to sustain Suc uptake and anabolic processes under conditions of elevated nitrogen supply. High Gln supply resulted in higher transcript levels of beta-conglycinin and oleosin. In the second study, analyses of soluble amino acid pools in two genetically related lines, NC103 and NC106 (low- and high-seed protein, respectively) showed that, in the light, NC106 accumulated higher levels of Asn and several other amino acids in developing cotyledons compared with NC103, whereas at the seed coat and apoplast levels both lines were similar. In the dark, NC103 accumulated Gln, Arg, and its precursors, suggesting a reduced availability of organic acids required for amino acid interconversions, while NC106 maintained higher levels of the pyruvate-derived amino acids Val, Leu, and Ile. Comparing NC103 and NC106, differences in seed composition were reflected in steady-state transcript levels of storage proteins and the lipogenic enzyme multi-subunit acetyl CoA carboxylase. In the third study, a positive correlation (P < or = 0.05) between free Asn in developing cotyledons and seed protein content at maturity was confirmed in a comparison of five unrelated field-grown cultivars. The findings support the hypothesis that high seed-protein content in soybean is determined by the capacity of the embryo to take up nitrogen sources and to synthesize storage proteins. Asn levels are probably tightly regulated in the embryo of high-protein lines, and may act as a metabolic signal of seed nitrogen status.}, number={417}, journal={JOURNAL OF EXPERIMENTAL BOTANY}, author={Hernandez-Sebastia, C and Marsolais, F and Saravitz, C and Israel, D and Dewey, RE and Huber, SC}, year={2005}, month={Jul}, pages={1951–1963} }
 @article{tang_novitzky_griffin_huber_dewey_2005, title={Oleate desaturase enzymes of soybean: evidence of regulation through differential stability and phosphorylation}, volume={44}, ISSN={["1365-313X"]}, DOI={10.1111/j.1365-313X.2005.02535.x}, abstractNote={Summary}, number={3}, journal={PLANT JOURNAL}, author={Tang, GQ and Novitzky, WP and Griffin, HC and Huber, SC and Dewey, RE}, year={2005}, month={Nov}, pages={433–446} }
 @article{tang_hardin_dewey_huber_2003, title={A novel C-terminal proteolytic processing of cytosolic pyruvate kinase, its phosphorylation and degradation by the proteasome in developing soybean seeds}, volume={34}, ISSN={["0960-7412"]}, DOI={10.1046/j.1365-313X.2003.01711.x}, abstractNote={Summary}, number={1}, journal={PLANT JOURNAL}, author={Tang, GQ and Hardin, SC and Dewey, R and Huber, SC}, year={2003}, month={Apr}, pages={77–93} }
 @article{siminszky_freytag_sheldon_dewey_2003, title={Co-expression of a NADPH : P450 reductase enhances CYP71A10-dependent phenylurea metabolism in tobacco}, volume={77}, ISSN={["0048-3575"]}, DOI={10.1016/j.pestbp.2003.08.001}, abstractNote={A soybean cytochrome P450 monooxygenase, designated CYP71A10, catalyzes the oxidative N-demethylation or ring methyl hydroxylation of a variety of phenylurea herbicides. The ectopic expression of CYP71A10 in tobacco was previously shown to be an effective means of enhancing whole plant tolerance to the compounds linuron and chlortoluron. Because P450 enzymes require ancillary proteins to catalyze the transfer of electrons from NADPH to the functional heme group of the P450, it is possible that the endogenous levels of these companion proteins may be insufficient to support the optimal activation of a highly expressed recombinant P450. In the present report, we have generated transgenic tobacco that simultaneously express CYP71A10 and a soybean P450 reductase. Transformed plants that express both CYP71A10 and the P450 reductase demonstrated 20–23% higher metabolic activity against phenylurea herbicides than control plants expressing CYP71A10 alone. These results suggest that herbicide tolerance strategies based on the expression of P450 genes may require concomitant expression of a cognate electron transport partner to fully exploit the herbicide metabolic capacity of the P450.}, number={2}, journal={PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY}, author={Siminszky, B and Freytag, AM and Sheldon, BS and Dewey, RE}, year={2003}, month={Oct}, pages={35–43} }
 @article{wilson_marquardt_novitzky_burton_wilcox_dewey_2001, title={Effect of alleles governing 16 : 0 concentration on glycerolipid composition in developing soybeans}, volume={78}, ISSN={["1558-9331"]}, DOI={10.1007/s11746-001-0264-5}, abstractNote={Abstract}, number={4}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Wilson, RF and Marquardt, TC and Novitzky, WP and Burton, JW and Wilcox, JR and Dewey, RE}, year={2001}, month={Apr}, pages={329–334} }
 @article{monks_aghoram_courtney_dewald_dewey_2001, title={Hyperosmotic stress induces the rapid phosphorylation of a soybean phosphatidylinositol transfer protein homolog through activation of the protein kinases SPK1 and SPK2}, volume={13}, ISSN={["1532-298X"]}, DOI={10.1105/tpc.13.5.1205}, abstractNote={Although phosphatidylinositol transfer proteins (PITPs) are known to serve critical functions in regulating a varied array of signal transduction processes in animals and yeast, the discovery of a similar class of proteins in plants occurred only recently. Here, we report the participation of Ssh1p, a soybean PITP-like protein, in the early events of osmosensory signal transduction in plants, a function not attributed previously to animal or yeast PITPs. Exposure of plant tissues to hyperosmotic stress led to the rapid phosphorylation of Ssh1p, a modification that decreased its ability to associate with membranes. An osmotic stress–activated Ssh1p kinase activity was detected in several plant species by presenting recombinant Ssh1p as a substrate in in-gel kinase assays. Elements of a similar osmosensory signaling pathway also were conserved in yeast, an observation that facilitated the identification of soybean protein kinases SPK1 and SPK2 as stress-activated Ssh1p kinases. This study reveals the activation of SPK1 and/or SPK2 and the subsequent phosphorylation of Ssh1p as two early successive events in a hyperosmotic stress–induced signaling cascade in plants. Furthermore, Ssh1p is shown to enhance the activities of a plant phosphatidylinositol 3-kinase and phosphatidylinositol 4-kinase, an observation that suggests that the ultimate function of Ssh1p in cellular signaling is to alter the plant’s capacity to synthesize phosphoinositides during periods of hyperosmotic stress.}, number={5}, journal={PLANT CELL}, author={Monks, DE and Aghoram, K and Courtney, PD and DeWald, DB and Dewey, RE}, year={2001}, month={May}, pages={1205–1219} }
 @article{shank_su_brglez_boss_dewey_boston_2001, title={Induction of lipid metabolic enzymes during the endoplasmic reticulum stress response in plants}, volume={126}, ISSN={["0032-0889"]}, DOI={10.1104/pp.126.1.267}, abstractNote={Abstract}, number={1}, journal={PLANT PHYSIOLOGY}, author={Shank, KJ and Su, P and Brglez, I and Boss, WF and Dewey, RE and Boston, RS}, year={2001}, month={May}, pages={267–277} }
 @article{wilson_marquardt_novitzky_burton_wilcox_kinney_dewey_2001, title={Metabolic mechanisms associated with alleles governing the 16 : 0 concentration of soybean oil}, volume={78}, ISSN={["1558-9331"]}, DOI={10.1007/s11746-001-0265-4}, abstractNote={Abstract}, number={4}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Wilson, RF and Marquardt, TC and Novitzky, WP and Burton, JW and Wilcox, JR and Kinney, AJ and Dewey, RE}, year={2001}, month={Apr}, pages={335–340} }
 @article{siminszky_sheldon_corbin_dewey_2000, title={A cytochrome P450 monooxygenase cDNA (CYP71A10) confers resistance to linuron in transgenic Nicotiana tabacum}, volume={48}, ISSN={["0043-1745"]}, DOI={10.1614/0043-1745(2000)048[0291:ACPMCC]2.0.CO;2}, abstractNote={Abstract The isolation of a Glycine max cytochrome P450 monooxygenase (P450) cDNA designated CYP71A10 that conferred linuron resistance to laboratory-grown, transgenic Nicotiana tabacum seedlings was previously reported. A nonsegregating transgenic N. tabacum line has been established that possesses two independent copies of the G. max CYP71A10 transgene. Five-week-old progeny plants of this selected line were grown in a controlled environmental chamber and treated with linuron using either pretransplant incorporated (PTI) or postemergence (POST) applications. CYP71A10-transformed N. tabacum was more tolerant to linuron than the wild type for both application methods. The transgenic N. tabacum line tolerated an approximately 16-fold and 12-fold higher rate of linuron than wild-type N. tabacum when the herbicide was applied PTI or POST, respectively. These results provide evidence that plant-derived P450 genes can be employed effectively to confer herbicide resistance to transgenic plants. Nomenclature: Cytochrome P450; linuron; Glycine max L. Merr. ‘Dare’, soybean; Nicotiana tabacum L. ‘SR1’, tobacco.}, number={3}, journal={WEED SCIENCE}, author={Siminszky, B and Sheldon, BS and Corbin, FT and Dewey, RE}, year={2000}, pages={291–295} }
 @article{pedra_delu_pirovani_contim_dewey_otoni_fontes_2000, title={Antisense and sense expression of a sucrose binding protein homologue gene from soybean in transgenic tobacco affects plant growth and carbohydrate partitioning in leaves}, volume={152}, ISSN={["1873-2259"]}, DOI={10.1016/S0168-9452(99)00223-X}, abstractNote={We isolated a cDNA from a soybean library, which encodes sucrose binding protein (SBP) homologue, designated S-64. To analyze the function of the SBP homologue, transgenic tobacco plants were obtained by introducing chimeric genes containing the s-64 coding region linked to the 35S CaMV promoter, either in the sense or antisense orientation, via Agrobacterium tumefaciens-mediated transformation. The accumulation of the SBP homologue was increased in transgenic plants expressing the heterologous sbp gene, whereas those expressing the antisense construct had reduced levels of the protein. The antisense transgenic plants developed symptoms characteristic of an inhibition of sucrose translocation and displayed a reduction in plant growth and development. In contrast, overexpression of the protein accelerated plant growth and the onset of flowering induction. The overall developmental performance of the transgenic plants was correlated with their photosynthetic rate under normal conditions. While photosynthesis in the antisense lines was decreased, in the sense lines photosynthetic rates were increased. Furthermore, both antisense repression and overexpression of the SBP homologue in transgenic lines altered carbohydrate partitioning in mature leaves. Taken together, these results indicate that S-64 protein is functionally analogous to SBP, representing an important component of the sucrose translocation pathway in plants.}, number={1}, journal={PLANT SCIENCE}, author={Pedra, JHF and Delu, N and Pirovani, CP and Contim, LAS and Dewey, RE and Otoni, WC and Fontes, EPB}, year={2000}, month={Mar}, pages={87–98} }
 @misc{siminszky_dewey_corbin_2000, title={Cytochrome P-450 constructs and method of producing herbicide-resistant transgenic plants}, volume={6,121,512}, number={2000 Sept. 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Siminszky, B. and Dewey, R. and Corbin, F.}, year={2000} }
 @article{goode_dewey_1999, title={Characterization of aminoalcoholphosphotransferases from Arabidopsis thaliana and soybean}, volume={37}, ISSN={["0981-9428"]}, DOI={10.1016/S0981-9428(99)80049-7}, abstractNote={Aminoalcoholphosphotransferases (AAPTs, EC 2.7.8.1 and EC 2.7.8.2) catalyze the condensation of 1,2-diacylglycerols with CDP-aminoalcohols to form phosphatidylaminoalcohols. Using a soybean (Glycine max) AAPT cDNA (GmAAPT1) as a heterologous hybridization probe, two additional plant AAPT-encoding cDNAs, designated AtAAPT1 and AtAAPT2, were isolated from an Arabidopsis thaliana cDNA library. Southern blot assays suggest that these two cDNAs may represent the only AAPT genes in this species. Heterologous expression of AtAAPT1 and AtAAPT2 in a yeast strain deficient in AAPT activities permitted the determination of substrate specificities of the two Arabidopsis enzymes (designated AtAAPT1p and AtAAPT2p). Although each AAPT isoform was capable of incorporating both CDP-ethanolamine and CDP-choline into phosphatidylethanolamine (PE) and phosphatidylcholine (PC), respectively, AtAAPT2p displayed a somewhat greater preference for CDP-choline over CDP-ethanolamine in comparison to AtAAPT1p. The previously characterized soybean AAPT, GmAAPT1p, and AtAAPT1p showed similar degrees of Ca2+ and CMP inhibition; AtAAPT2p, however, was inhibited to a lesser degree in the presence of these compounds. All three plant AAPTs are capable of catalyzing the reverse reaction, generating CDP-choline and diacylglycerol from PC in the presence of CMP. Finally, overexpression of the soybean AAPT cDNA in transgenic tobacco using a strong constitutive promoter resulted in only modest increases in enzymatic activity, suggesting the possibility of post-transcriptional regulation.}, number={6}, journal={PLANT PHYSIOLOGY AND BIOCHEMISTRY}, author={Goode, JH and Dewey, RE}, year={1999}, month={Jun}, pages={445–457} }
 @article{siminszky_corbin_ward_fleischmann_dewey_1999, title={Expression of a soybean cytochrome P450 monooxygenase cDNA in yeast and tobacco enhances the metabolism of phenylurea herbicides}, volume={96}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.96.4.1750}, abstractNote={
            A strategy based on the random isolation and screening of soybean
 cDNAs encoding cytochrome P450 monooxygenases (P450s) was used in an
 attempt to identify P450 isozymes involved in herbicide metabolism.
 Nine full-length (or near-full-length) P450 cDNAs representing eight
 distinct P450 families were isolated by using PCR-based technologies.
 Five of the soybean P450 cDNAs were expressed successfully in yeast,
 and microsomal fractions generated from these strains were tested for
 their potential to catalyze the metabolism of 10 herbicides and 1
 insecticide.
            In vitro
            enzyme assays showed that the gene
 product of one heterologously expressed P450 cDNA (CYP71A10)
 specifically catalyzed the metabolism of phenylurea herbicides,
 converting four herbicides of this class (fluometuron, linuron,
 chlortoluron, and diuron) into more polar compounds. Analyses of the
 metabolites suggest that the CYP71A10 encoded enzyme functions
 primarily as an
            N
            -demethylase with regard to
 fluometuron, linuron, and diuron, and as a ring-methyl hydroxylase when
 chlortoluron is the substrate.
            In vivo
            assays using
 excised leaves demonstrated that all four herbicides were more readily
 metabolized in CYP71A10-transformed tobacco compared with control
 plants. For linuron and chlortoluron, CYP71A10-mediated herbicide
 metabolism resulted in significantly enhanced tolerance to these
 compounds in the transgenic plants.
          }, number={4}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Siminszky, B and Corbin, FT and Ward, ER and Fleischmann, TJ and Dewey, RE}, year={1999}, month={Feb}, pages={1750–1755} }
 @misc{drobak_dewey_boss_1999, title={Phosphoinositide kinases and the synthesis of polyphosphoinositides in higher plant cells}, volume={189}, ISBN={["0-12-364593-X"]}, ISSN={["0074-7696"]}, DOI={10.1016/S0074-7696(08)61386-8}, abstractNote={Phosphoinositides are a family of inositol-containing phospholipids which are present in all eukaryotic cells. Although in most cells these lipids, with the exception of phosphatidylinositol, constitute only a very minor proportion of total cellular lipids, they have received immense attention by researchers in the past 15-20 years. This is due to the discovery that these lipids, rather than just having structural functions, play key roles in a wide range of important cellular processes. Much less is known about the plant phosphoinositides than about their mammalian counterparts. However, it has been established that a functional phosphoinositide system exists in plant cells and it is becoming increasingly clear that inositol-containing lipids are likely to play many important roles throughout the life of a plant. It is not our intention to give an exhaustive overview of all aspects of the field, but rather we focus on the phosphoinositide kinases responsible for the synthesis of all phosphorylated forms of phosphatidylinositol. Also, we mention some of the aspects of current phosphoinositide research which, in our opinion, are most likely to provide a suitable starting point for further research into the role of phosphoinositides in plants.}, journal={INTERNATIONAL REVIEW OF CYTOLOGY - A SURVEY OF CELL BIOLOGY, VOL 189}, author={Drobak, BK and Dewey, RE and Boss, WF}, year={1999}, pages={95–130} }
 @misc{modified urf13-t protein_1998, volume={5,807,998}, number={1998 Sept. 15}, publisher={Washington, DC: U.S. Patent and Trademark Office}, year={1998} }
 @article{kearns_monks_fang_rivas_courtney_chen_prestwich_theibert_dewey_bankaitis_1998, title={Novel developmentally regulated phosphoinositide binding proteins from soybean whose expression bypasses the requirement for an essential phosphatidylinositol transfer protein in yeast}, volume={17}, ISSN={["0261-4189"]}, DOI={10.1093/emboj/17.14.4004}, abstractNote={Phosphatidylinositol transfer proteins (PITPs) have been shown to play important roles in regulating a number of signal transduction pathways that couple to vesicle trafficking reactions, phosphoinositide‐driven receptor‐mediated signaling cascades, and development. While yeast and metazoan PITPs have been analyzed in some detail, plant PITPs remain entirely uncharacterized. We report the identification and characterization of two soybean proteins, Ssh1p and Ssh2p, whose structural genes were recovered on the basis of their abilities to rescue the viability of PITP‐deficient Saccharomyces cerevisiae strains. We demonstrate that, while both Ssh1p and Ssh2p share ∼25% primary sequence identity with yeast PITP, these proteins exhibit biochemical properties that diverge from those of the known PITPs. Ssh1p and Ssh2p represent high‐affinity phosphoinositide binding proteins that are distinguished from each other both on the basis of their phospholipid binding specificities and by their substantially non‐overlapping patterns of expression in the soybean plant. Finally, we show that Ssh1p is phosphorylated in response to various environmental stress conditions, including hyperosmotic stress. We suggest that Ssh1p may function as one component of a stress response pathway that serves to protect the adult plant from osmotic insult.}, number={14}, journal={EMBO JOURNAL}, author={Kearns, MA and Monks, DE and Fang, M and Rivas, MP and Courtney, PD and Chen, J and Prestwich, GD and Theibert, AB and Dewey, RE and Bankaitis, VA}, year={1998}, month={Jul}, pages={4004–4017} }
 @misc{maize cytoplasmic male sterility type t (cms-t) mitochondria dna_1997, volume={5,660,983}, number={1997 Aug. 26}, publisher={Washington, DC: U.S. Patent and Trademark Office}, year={1997} }
 @misc{levings_dewey_braun_1997, title={Method of detecting toxins using host cells expressing an urf13-T gene}, volume={5,597,698}, number={1997 Jan. 28}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Levings, C. S. and Dewey, R. E. and Braun, C. J.}, year={1997} }
 @inbook{monks_goode_dinsmore_dewey_1997, title={Phosphatidylcholine biosynthesis in soybeans: The cloning and characterization of genes encoding enzymes of the nucleotide pathway}, DOI={10.1007/978-94-017-2662-7_35}, booktitle={Physiology, biochemistry, and molecular biology of plant lipids}, publisher={Dordrecht; Boston: Kluwer Academic}, author={Monks, D. E. and Goode, J. H. and Dinsmore, P. K. and Dewey, R. E.}, editor={J. P. Williams, M. U. Khan and Lem, N. W.Editors}, year={1997}, pages={110–112} }
 @misc{levings_dewey_braun_1996, title={Method of detecting toxin-insensitive urf13-T protein}, volume={5,576,179}, number={1996 Nov. 19}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Levings, C. S. and Dewey, R. E. and Braun, C. J.}, year={1996} }
 @misc{levings_dewey_braun_1995, title={Modified unF-13 protein and gene}, volume={5,409,837}, number={1995 Apr. 25}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Levings, C. S. and Dewey, R. E. and Braun, C. J.}, year={1995} }
 @article{dewey_wilson_novitzky_goode_1994, title={THE AAPT1 GENE OF SOYBEAN COMPLEMENTS A CHOLINEPHOSPHOTRANSFERASE-DEFICIENT MUTANT OF YEAST}, volume={6}, ISSN={["1040-4651"]}, DOI={10.1105/tpc.6.10.1495}, abstractNote={Aminoalcoholphosphotransferases (AAPTases) utilize diacylglycerols and cytidine diphosphate (CDP)-aminoalcohols as substrates in the synthesis of the abundant membrane lipids phosphatidylcholine and phosphatidylethanolamine. A soybean cDNA encoding an AAPTase that demonstrates high levels of CDP-choline:sn-1,2-diacylglycerol cholinephosphotransferase activity was isolated by complementation of a yeast strain deficient in this function and was designated AAPT1. The deduced amino acid sequence of the soybean cDNA showed nearly equal similarity to each of the two characterized AAPTase sequences from yeast, cholinephosphotransferase and ethanolaminephosphotransferase (CDP-ethanolamine:sn-1,2-diacylglycerol ethanolaminephosphotransferase). Moreover, assays of soybean AAPT1-encoded enzyme activity in yeast microsomal membranes revealed that the addition of CDP-ethanolamine to the reaction inhibited incorporation of 14C-CDP-choline into phosphatidylcholine in a manner very similar to that observed using unlabeled CDP-choline. Although DNA gel blot analysis suggested that AAPT1-like sequences are represented in soybean as a small multigene family, the same AAPT1 isoform isolated from a young leaf cDNA library was also recovered from a developing seed cDNA library. Expression assays in yeast using soybean AAPT1 cDNAs that differed only in length suggested that sequences in the 5'leader of the transcript were responsible for the negative regulation of gene activity in this heterologous system. The inhibition of translation mediated by a short open reading frame located 124 bp upstream of the AAPT1 reading frame is one model proposed for the observed down-regulation of gene activity.}, number={10}, journal={PLANT CELL}, author={DEWEY, RE and WILSON, RF and NOVITZKY, WP and GOODE, JH}, year={1994}, month={Oct}, pages={1495–1507} }
 @article{dewey_timothy_levings_1991, title={CHIMERIC MITOCHONDRIAL GENES EXPRESSED IN THE C-MALE-STERILE CYTOPLASM OF MAIZE}, volume={20}, ISSN={["0172-8083"]}, DOI={10.1007/BF00334775}, abstractNote={Aberrant recombinations involving the mitochondrial atp9, atp6 and coxII genes have created unique chimeric sequences in the C male-sterile cytoplasm (cms-C) of maize. An apparent consequence of the rearrangements is the interchanging of transcriptional and/or translational regulatory signals for these genes, and alterations in the reading frames encoding the atp6 and coxII genes in the C cytoplasm. Particularly unusual is the organization of the atp6 gene in cms-C mitochondria, designated atp6-C. The atp6-C sequence is a triple gene fusion product comprised of DNAs derived from atp9, atp6 and an open reading frame of unknown origin. Although there is no direct evidence indicating that these chimeric genes are responsible for the cytoplasmic male sterility (cms) trait, their novel arrangements and the strong correlation between these genes and the C type of male sterility suggest such a role.}, number={6}, journal={CURRENT GENETICS}, author={DEWEY, RE and TIMOTHY, DH and LEVINGS, CS}, year={1991}, pages={475–482} }
 @article{dewey_levings_timothy_1986, title={Novel recombinations in the maize mitochondrial genome produce a unique transcriptional unit in the texas male-sterile cytoplasm}, volume={44}, DOI={10.1016/0092-8674(86)90465-4}, abstractNote={We have characterized a 3547 bp DNA fragment from male-sterile (cms-T) maize mitochondria, designated TURF 2H3, selected because of its unique and abundant transcripts. Sequence analysis indicated that TURF 2H3 originated by recombinations among portions of the flanking and/or coding regions of the maize mitochondrial 26S ribosomal gene, the ATPase subunit 6 gene, and the chloroplast tRNA-Arg gene. TURF 2H3 contains two long open reading frames that could encode polypeptides of 12,961 Mr and 24,675 Mr. The larger open reading frame hybridizes to transcripts in all maize cytoplasms, the smaller to transcripts only in T cytoplasm. TURF 2H3 transcripts appear to be uniquely altered in cms-T plants restored to fertility by the nuclear restorer genes Rf1 and Rf2. A possible relationship between TURF 2H3, nuclear restorer genes, and the male sterility trait in T cytoplasm is suggested.}, number={3}, journal={Cell}, author={Dewey, R. E. and Levings, C. S. and Timothy, D. H.}, year={1986}, pages={439–449} }