Research Assistant Louisiana State University Department of Biological Sciences new iberia, Louisiana
Body of Abstract: Extremophytes that can complete their life cycle at high salinities are a useful resource for determining the underlying genetic mechanisms of salt stress tolerance. Often genetic responses to salt stress in plants are examined at early developmental or non-reproductive stages despite the growing evidence that salt stress during reproductive growth stages lowers crop yields. Schrenkiella parvula is an extremophyte model adapted to high salinities with lower costs to growth when compared to Arabidopsis or salt stress-sensitive crops. From a transcriptome atlas created for S. parvula, a previous study found that the highest number of tissue-preferentially expressed genes were in reproductive tissues. This led us to hypothesize that S. parvula uses specific genes and networks during its transition to reproductive growth and during seed maturation to survive high salinities. Here, we examined transcriptional profiles of flowers, siliques, and seeds of S. parvula when treated with 150 mM NaCl compared to control conditions. Additionally, we compared transcriptomic differences when plants were treated with salt before and after the onset of flowers to identify potential transcriptomic adjustments that affect flowering and seed development. We assessed the tissue and condition specific expression of differently expressed genes and their functional associations. We further tested for Abscisic acid (ABA)-regulated salt stress responses in the differently expressed genes by searching for ABA-responsive element binding factors (ABFs) using DAP-seq data generated for S. parvula in a previous study. We were able to identify gene regulatory networks differentially regulated under salt stress that may facilitate successful reproduction under high salinity in S. parvula. This analysis in Schrenkiella parvula provides insight into the survival strategies that may coordinate necessary responses from multiple tissues and developmental stages to survive abiotic stress. These findings have the potential to inform future crop designs aimed for building stress resilient growth in resource limited environments.