Hernando Carlos Esteban, García Hourquet Mariano, de Leone María José, Careno Daniel, Iserte Javier, Mora Garcia Santiago, Yanovsky Marcelo Javier
Comparative Genomics of Plant Development Laboratory, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, Fundación Instituto Leloir, Buenos Aires, Argentina.
Front Plant Sci. 2019 Aug 13;10:1019. doi: 10.3389/fpls.2019.01019. eCollection 2019.
Because of their sessile nature, plants have adopted varied strategies for growing and reproducing in an ever-changing environment. Control of mRNA levels and pre-mRNA alternative splicing are key regulatory layers that contribute to adjust and synchronize plant growth and development with environmental changes. Transcription and alternative splicing are thought to be tightly linked and coordinated, at least in part, through a network of transcriptional and splicing regulatory factors that interact with the carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II. One of the proteins that has been shown to play such a role in yeast and mammals is pre-mRNA-PROCESSING PROTEIN 40 (PRP40, also known as CA150, or TCERG1). In plants, members of the PRP40 family have been identified and shown to interact with the CTD of RNA Pol II, but their biological functions remain unknown. Here, we studied the role of AtPRP40C, in growth, development and stress tolerance, as well as its impact on the global regulation of gene expression programs. We found that the knockout mutants display a late-flowering phenotype under long day conditions, associated with minor alterations in red light signaling. An RNA-seq based transcriptome analysis revealed differentially expressed genes related to biotic stress responses and also differentially expressed as well as differentially spliced genes associated with abiotic stress responses. Indeed, the characterization of stress responses in prp40c mutants revealed an increased sensitivity to salt stress and an enhanced tolerance to pv. () infections. This constitutes the most thorough analysis of the transcriptome of a prp40 mutant in any organism, as well as the first characterization of the molecular and physiological roles of a member of the PRP40 protein family in plants. Our results suggest that PRP40C is an important factor linking the regulation of gene expression programs to the modulation of plant growth, development, and stress responses.
由于植物固着生长的特性，它们在不断变化的环境中采用了多种生长和繁殖策略。mRNA水平的调控以及前体mRNA可变剪接是关键的调控层面，有助于使植物的生长发育与环境变化相适应并同步。转录和可变剪接被认为紧密相连且相互协调，至少部分是通过与RNA聚合酶II最大亚基的羧基末端结构域（CTD）相互作用的转录和剪接调控因子网络来实现的。在酵母和哺乳动物中已证明发挥此类作用的一种蛋白质是前体mRNA加工蛋白40（PRP40，也称为CA150或TCERG1）。在植物中，已鉴定出PRP40家族成员，并表明它们与RNA聚合酶II的CTD相互作用，但其生物学功能仍不清楚。在这里，我们研究了AtPRP40C在生长、发育和胁迫耐受性方面的作用，以及它对基因表达程序全局调控的影响。我们发现敲除突变体在长日照条件下表现出晚花表型，与红光信号的轻微改变有关。基于RNA测序的转录组分析揭示了与生物胁迫反应相关的差异表达基因，以及与非生物胁迫反应相关的差异表达和差异剪接基因。实际上，对prp40c突变体胁迫反应的表征揭示了其对盐胁迫的敏感性增加以及对青枯菌（Pseudomonas syringae pv. tomato (Pto)）感染的耐受性增强。这是对任何生物体中prp40突变体转录组最全面的分析，也是PRP40蛋白家族成员在植物中的分子和生理作用的首次表征。我们的结果表明，PRP40C是将基因表达程序调控与植物生长、发育和胁迫反应调节联系起来的重要因子。
