@article{land_sheppard_doherty_perera_2024, title={Conserved plant transcriptional responses to microgravity from two consecutive spaceflight experiments}, volume={14}, ISSN={["1664-462X"]}, url={http://dx.doi.org/10.3389/fpls.2023.1308713}, DOI={10.3389/fpls.2023.1308713}, abstractNote={IntroductionUnderstanding how plants adapt to the space environment is essential, as plants will be a valuable component of long duration space missions. Several spaceflight experiments have focused on transcriptional profiling as a means of understanding plant adaptation to microgravity. However, there is limited overlap between results from different experiments. Differences in experimental conditions and hardware make it difficult to find a consistent response across experiments and to distinguish the primary effects of microgravity from other spaceflight effects.}, journal={FRONTIERS IN PLANT SCIENCE}, author={Land, Eric S. and Sheppard, James and Doherty, Colleen J. and Perera, Imara Y.}, year={2024}, month={Jan} }
 @article{barcenilla_meyers_castillo-gonzalez_young_min_song_phadke_land_canaday_perera_et al._2023, title={Arabidopsis telomerase takes off by uncoupling enzyme activity from telomere length maintenance in space}, volume={14}, ISSN={["2041-1723"]}, url={http://dx.doi.org/10.1038/s41467-023-41510-4}, DOI={10.1038/s41467-023-41510-4}, abstractNote={Abstract}, number={1}, journal={NATURE COMMUNICATIONS}, author={Barcenilla, Borja Barbero and Meyers, Alexander D. and Castillo-Gonzalez, Claudia and Young, Pierce and Min, Ji-Hee and Song, Jiarui and Phadke, Chinmay and Land, Eric and Canaday, Emma and Perera, Imara Y. and et al.}, year={2023}, month={Nov} }
 @article{land_canaday_meyers_wyatt_perera_2023, title={Bridging the gap: parallel profiling of ribosome associated and total RNA species can identify transcriptional regulatory mechanisms of plants in spaceflight}, volume={18}, ISSN={["1742-9153"]}, url={https://doi.org/10.1080/17429145.2023.2248173}, DOI={10.1080/17429145.2023.2248173}, abstractNote={As plants are an essential component of sustainable life support systems, long-duration space missions will require a sophisticated understanding of plant adaptations to spaceflight and microgravity. For many years, transcriptional profiling of steady state mRNA abundances has been used as measure of plant adaptations to the space environment. However, measured changes in transcript abundances are often not reflected in corresponding changes in the proteome due regulatory processes governing translation. Translating ribosome affinity purification (TRAP) is a technique which selectively targets ribosome bound mRNAs for isolation and downstream sequencing. Comparing profiles of ribosome associated mRNAs with total mRNAs provides insight into the translatome and may more accurately inform on the cellular responses to the spaceflight environment. Toward that goal, this work describes a methodology developed ahead of the APEx-07 flight mission.}, number={1}, journal={JOURNAL OF PLANT INTERACTIONS}, author={Land, Eric S. and Canaday, Emma and Meyers, Alexander and Wyatt, Sarah and Perera, Imara Y.}, year={2023}, month={Dec} }
 @article{meyers_land_perera_canaday_wyatt_2022, title={Polyethersulfone (PES) Membrane on Agar Plates as a Plant Growth Platform for Spaceflight}, url={http://dx.doi.org/10.2478/gsr-2022-0004}, DOI={10.2478/gsr-2022-0004}, abstractNote={Abstract}, journal={Gravitational and Space Research}, author={Meyers, Alexander and Land, Eric and Perera, Imara and Canaday, Emma and Wyatt, Sarah E.}, year={2022}, month={Jan} }
 @article{land_cridland_craige_dye_hildreth_helm_gillaspy_perera_2021, title={A Role for Inositol Pyrophosphates in the Metabolic Adaptations to Low Phosphate in Arabidopsis}, volume={11}, ISSN={["2218-1989"]}, url={https://doi.org/10.3390/metabo11090601}, DOI={10.3390/metabo11090601}, abstractNote={Phosphate is a major plant macronutrient and low phosphate availability severely limits global crop productivity. In Arabidopsis, a key regulator of the transcriptional response to low phosphate, phosphate starvation response 1 (PHR1), is modulated by a class of signaling molecules called inositol pyrophosphates (PP-InsPs). Two closely related diphosphoinositol pentakisphosphate enzymes (AtVIP1 and AtVIP2) are responsible for the synthesis and turnover of InsP8, the most implicated molecule. This study is focused on characterizing Arabidopsis vip1/vip2 double mutants and their response to low phosphate. We present evidence that both local and systemic responses to phosphate limitation are dampened in the vip1/vip2 mutants as compared to wild-type plants. Specifically, we demonstrate that under Pi-limiting conditions, the vip1/vip2 mutants have shorter root hairs and lateral roots, less accumulation of anthocyanin and less accumulation of sulfolipids and galactolipids. However, phosphate starvation response (PSR) gene expression is unaffected. Interestingly, many of these phenotypes are opposite to those exhibited by other mutants with defects in the PP-InsP synthesis pathway. Our results provide insight on the nexus between inositol phosphates and pyrophosphates involved in complex regulatory mechanisms underpinning phosphate homeostasis in plants.}, number={9}, journal={METABOLITES}, publisher={MDPI AG}, author={Land, Eric S. and Cridland, Caitlin A. and Craige, Branch and Dye, Anna and Hildreth, Sherry B. and Helm, Rich F. and Gillaspy, Glenda E. and Perera, Imara Y.}, year={2021}, month={Sep} }
 @article{cridland_land_williams_hildreth_helm_perera_gillaspy_2021, title={Lipid remodeling in response to low phosphate is modulated by inositol pyrophosphates}, url={http://dx.doi.org/10.1096/fasebj.2021.35.s1.04115}, DOI={10.1096/fasebj.2021.35.s1.04115}, abstractNote={Under changing environmental conditions, plants are able to modulate their lipids to respond to varying nutrient availability. Phosphate (Pi) is an essential nutrient for plants, required for plant growth and seed viability. Under Pi stress, plants undergo dynamic morphological and metabolism changes to leverage available Pi, including the modulation of lipids. Plants have been shown to “remodel” their lipid membrane profiles under phosphate starvation, degrading phospholipids in the cell membranes and utilizing the generated phosphorus for essential biological processes. By concomitantly inducing a phospholipid hydrolysis pathway and galactolipid biosynthetic pathway, membrane phospholipids are replaced by non-phosphorus containing galactolipids and sulfolipids. The inositol phosphate (InsP) signaling pathway is a crucial element of the plant's ability to respond to changing energy conditions. Inositol hexakisphosphate (InsP6) is the most abundant InsP signaling molecule and can be phosphorylated further by VIP kinases, resulting in inositol pyrophosphates (PP-InsPs). PP-InsPs have high energy bonds and have been linked to maintaining Pi and energy homeostasis in yeast and plants. Using liquid chromatography-mass spectrometry and tandem mass spectrometry, we have examined the lipid profiles of three Arabidopsis PP-InsP mutants, in response to Pi depletion, to address the role of PP-InsPs in Pi sensing. Our results suggest that PP-InsPs play a crucial role in Pi sensing and are involved in the regulation of lipid biosynthesis. Furthermore, the changes in the abundance of lipids suggest a possible direction for future seed oil engineering strategies.}, journal={The FASEB Journal}, author={Cridland, Caitlin and Land, Eric and Williams, Phoebe and Hildreth, Sherry and Helm, Rich and Perera, Imara and Gillaspy, Glenda}, year={2021}, month={May} }
 @article{tolsma_ryan_torres_richards_richardson_land_perera_doherty_2021, title={The Circadian-clock Regulates the Arabidopsis Gravitropic Response}, url={https://doi.org/10.2478/gsr-2021-0014}, DOI={10.2478/gsr-2021-0014}, abstractNote={Abstract}, journal={Gravitational and Space Research}, author={Tolsma, Joseph S. and Ryan, Kaetlyn T. and Torres, Jacob J. and Richards, Jeffrey T. and Richardson, Zach and Land, Eric S. and Perera, Imara Y. and Doherty, Colleen J}, year={2021}, month={Jan} }
 @article{sheppard_land_toennisson_doherty_perera_2021, title={Uncovering Transcriptional Responses to Fractional Gravity in Arabidopsis Roots}, volume={11}, ISSN={["2075-1729"]}, url={https://doi.org/10.3390/life11101010}, DOI={10.3390/life11101010}, abstractNote={Although many reports characterize the transcriptional response of Arabidopsis seedlings to microgravity, few investigate the effect of partial or fractional gravity on gene expression. Understanding plant responses to fractional gravity is relevant for plant growth on lunar and Martian surfaces. The plant signaling flight experiment utilized the European Modular Cultivation System (EMCS) onboard the International Space Station (ISS). The EMCS consisted of two rotors within a controlled chamber allowing for two experimental conditions, microgravity (stationary rotor) and simulated gravity in space. Seedlings were grown for 5 days under continuous light in seed cassettes. The arrangement of the seed cassettes within each experimental container results in a gradient of fractional g (in the spinning rotor). To investigate whether gene expression patterns are sensitive to fractional g, we carried out transcriptional profiling of root samples exposed to microgravity or partial g (ranging from 0.53 to 0.88 g). Data were analyzed using DESeq2 with fractional g as a continuous variable in the design model in order to query gene expression across the gravity continuum. We identified a subset of genes whose expression correlates with changes in fractional g. Interestingly, the most responsive genes include those encoding transcription factors, defense, and cell wall-related proteins and heat shock proteins.}, number={10}, journal={LIFE-BASEL}, author={Sheppard, James and Land, Eric S. and Toennisson, Tiffany Aurora and Doherty, Colleen J. and Perera, Imara Y.}, year={2021}, month={Oct} }
 @article{gillaspy_adepoju_land_williams_donahue_cridland_freed_perera_2019, title={Inositol Pyrophosphates and Phosphate Sensing in Plants}, url={http://dx.doi.org/10.1096/fasebj.2019.33.1_supplement.480.1}, DOI={10.1096/fasebj.2019.33.1_supplement.480.1}, abstractNote={Phosphate (Pi) is an essential nutrient for plants, required for plant growth and seed viability. Under Pi stress, plants undergo dynamic changes to leverage available Pi. One class of signaling molecules implicated in the Pi sensing pathway is the inositol pyrophosphates (PPx‐InsPs). PPx‐InsPs have high energy bonds, and have been linked to maintaining Pi and energy homeostasis in plants, yeast, and humans. In plants, PPx‐InsPs are thought to function in sensing Pi changes by binding to proteins containing an SPX domain. One particular SPX protein binds to PPx‐InsPs which prevents a transcription factor from activating transcription of the so‐called phosphate starvation response (PSR) genes. Plants are known to accumulate two common PPx‐InsPs, PP‐InsP5 (called InsP7) and PP2‐InsP4 (called InsP8), but the synthesis pathway has not yet been elucidated. We have identified and characterized the plant VIP kinases, enzymes that likely function as PP‐InsP5 kinases. The identity of a plant inositol kinase that can phosphorylate InsP6, resulting in PP‐InsP5, however, has remained elusive. We will describe our recent results in characterizing this pathway, and genetic mutants key for understanding inositol kinase gene function in plants. Our results support a model in which InsP7 and InsP8 function to turn off the PSR in plants.}, journal={The FASEB Journal}, author={Gillaspy, Glenda and Adepoju, Olusegun and Land, Eric and Williams, Sarah Phoebe and Donahue, Janet and Cridland, Caitlin and Freed, Catherine and Perera, Imara}, year={2019}, month={Apr} }
 @article{adepoju_williams_craige_cridland_sharpe_brown_land_perera_mena_sobrado_et al._2019, title={Inositol Trisphosphate Kinase and Diphosphoinositol Pentakisphosphate Kinase Enzymes Constitute the Inositol Pyrophosphate Synthesis Pathway in Plants}, url={http://dx.doi.org/10.1101/724914}, DOI={10.1101/724914}, abstractNote={ABSTRACT}, author={Adepoju, Olusegun and Williams, Sarah P. and Craige, Branch and Cridland, Caitlin A. and Sharpe, Amanda K. and Brown, Anne M. and Land, Eric and Perera, Imara Y. and Mena, Didier and Sobrado, Pablo and et al.}, year={2019}, month={Aug} }
 @inbook{dalal_land_vasani_he_smith_rodriguez-welsh_perera_sederoff_2015, title={Methods for RNA Profiling of Gravi-Responding Plant Tissues}, volume={1309}, ISBN={9781493926961 9781493926978}, ISSN={1064-3745 1940-6029}, url={http://dx.doi.org/10.1007/978-1-4939-2697-8_9}, DOI={10.1007/978-1-4939-2697-8_9}, abstractNote={Plant transcriptional responses to gravity stimulation by reorientation are among the fastest measured in any tissue or species. Upon reorientation, changes in abundance of specific mRNAs can be measured within seconds or minutes, for plastid or nuclear encoded genes, respectively. Identifying fast gravity-induced transcripts has been made possible by the development of high-throughput technology for qualitative and quantitative RNA analysis. RNA profiling has undergone further rapid development due to its enormous potential in basic sciences and medical applications. We describe here the current and most widely used methods to profile the changes in an entire transcriptome by high-throughput sequencing of RNA fractions (RNAseq) and single gene transcript analysis using real-time quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR).}, booktitle={Methods in Molecular Biology}, publisher={Springer New York}, author={Dalal, Jyoti and Land, Eric and Vasani, Naresh and He, Luyan and Smith, Caroline and Rodriguez-Welsh, Maria and Perera, Imara Y. and Sederoff, Heike}, year={2015}, pages={91–117} }
 @article{desai_rangarajan_donahue_williams_land_mandal_phillippy_perera_raboy_gillaspy_2014, title={Two inositol hexakisphosphate kinases drive inositol pyrophosphate synthesis in plants}, volume={80}, ISSN={0960-7412}, url={http://dx.doi.org/10.1111/tpj.12669}, DOI={10.1111/tpj.12669}, abstractNote={Summary}, number={4}, journal={The Plant Journal}, publisher={Wiley}, author={Desai, Mintu and Rangarajan, Padma and Donahue, Janet L. and Williams, Sarah P. and Land, Eric S. and Mandal, Mihir K. and Phillippy, Brian Q. and Perera, Imara Y. and Raboy, Victor and Gillaspy, Glenda E.}, year={2014}, month={Oct}, pages={642–653} }
 @article{smith_desai_land_perera_2013, title={A ROLE FOR LIPID-MEDIATED SIGNALING IN PLANT GRAVITROPISM}, volume={100}, ISSN={["0002-9122"]}, DOI={10.3732/ajb.1200355}, abstractNote={Gravitropism is a universal plant response. It is initiated by the sensing of the primary signal (mass or pressure), which is then converted into chemical signals that are transduced and propagated in a precise spatial and temporal fashion, resulting in a differential growth response. Our thesis is that membrane lipids and lipid‐mediated signaling pathways play critical roles in the initial signaling and in the establishment of polarity. In this review, we highlight results from recent literature and discuss the major questions that remain unanswered.}, number={1}, journal={AMERICAN JOURNAL OF BOTANY}, author={Smith, Caroline M. and Desai, Mintu and Land, Eric S. and Perera, Imara Y.}, year={2013}, month={Jan}, pages={153–160} }