Modulation of RNA processing by abscisic acid

植物激素脱落酸（ABA）调节植物的各种发育和胁迫诱导过程。一些ABA应答基因编码rna结合或rna加工蛋白，最近对拟南芥ABA敏感突变体的研究表明ABA参与转录后mRNA加工。拟南芥基因组编码超过200种假定的rna结合蛋白；其中一半是植物特有的。rna结合蛋白介导mRNA的合成、剪接、转运、翻译和降解，通过影响转录物丰度，rna结合蛋白在微调细胞蛋白表达方面发挥着重要的调节作用。我们对植物rna结合蛋白的认识非常有限，只有少数植物rna结合蛋白被表征，关于其作用的调节机制的信息很少或没有。所研究的植物rna结合蛋白大多与ABA直接或间接相关。我已经确定了RNA结合蛋白，开花时间控制位点A (FCA)，作为植物中第一个ABA受体，并提供了植物激素与RNA加工的第一个直接联系。通过这个研究项目，我试图了解ABA调节植物细胞中RNA加工的机制。本研究的目的是探讨ABA在调节RNA加工、确定RNA结合特异性以及RNA结合蛋白相互作用中的可能参与。这项研究将包括体内和体外研究，利用两种ABA受体蛋白，拟南芥FCA及其谷类同源物ABAP1。我的研究项目将对基因表达调控机制的现有知识做出贡献，并将成为第一个研究植物中激素调控RNA代谢的人。我的研究项目将对植物生长发育的基本过程产生直接而深远的影响，并可用于选择具有高产潜力和对生物和非生物胁迫具有高耐受性的农业重要作物。

The phytohormone abscisic acid (ABA) regulates various developmental and stress-induced processes in plants. Several ABA response genes encode for RNA-binding or RNA-processing proteins, and recent studies on Arabidopsis ABA-sensitivity mutants have shown ABA involvement in post-transcriptional mRNA processing. Arabidopsis genome encodes more than 200 putative RNA-binding proteins; half of which are plant-specific. RNA-binding proteins mediate mRNA synthesis, splicing, transport, translation and degradation and by influencing transcript abundance, RNA-binding proteins provide a major regulatory role in fine-tuning cellular protein expression.Our knowledge of plant RNA-binding proteins is very limited and only a few plant RNA-binding proteins are characterized, with little or no information available on the mechanism by which their action is regulated. Most of the studied RNA-binding proteins in plants are directly or indirectly linked to ABA.I have identified the RNA binding protein, Flowering Time Control Locus A (FCA), as the first ABA receptor in plants and provided the first direct link of a plant hormone to RNA processing.Through this research program, I seek to understand the mechanisms by which ABA regulates RNA processing in plant cells. The objectives of this research are to investigate possible involvement of ABA in regulating RNA processing, determining of RNA binding specificity, and in the interactions of the RNA-binding proteins. This research will comprise both in vivo and in vitro studies, utilizing two ABA receptor proteins, the Arabidopsis FCA and its cereal homologue, ABAP1. My research program will contribute to the existing knowledge on the mechanisms that regulate gene expression and will be the first to look at hormonal regulation of RNA metabolism in plants. My research progrm will have immediate and far-reaching impacts on the fundamental processes of plant growth and development, and can be applied to select for agriculturally important crops that possess high-yield potential and exert high tolerance to biotic and abiotic stresses.