Cambridge Centre for Proteomics, Cambridge Systems Biology Centre, and Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1GA, UK.
Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, 23955-6900, Thuwal, Kingdom of Saudi Arabia.
BMC Plant Biol. 2019 Apr 11;19(1):139. doi: 10.1186/s12870-019-1750-x.
RNA-binding proteins (RBPs) are increasingly recognized as regulatory component of post-transcriptional gene expression. RBPs interact with mRNAs via RNA-binding domains and these interactions affect RNA availability for translation, RNA stability and turn-over thus affecting both RNA and protein expression essential for developmental and stimulus specific responses. Here we investigate the effect of severe drought stress on the RNA-binding proteome to gain insights into the mechanisms that govern drought stress responses at the systems level.
Label-free mass spectrometry enabled the identification 567 proteins of which 150 significantly responded to the drought-induced treatment. A gene ontology analysis revealed enrichment in the "RNA binding" and "RNA processing" categories as well as biological processes such as "response to abscisic acid" and "response to water deprivation". Importantly, a large number of the stress responsive proteins have not previously been identified as RBPs and include proteins in carbohydrate metabolism and in the glycolytic and citric acid pathways in particular. This suggests that RBPs have hitherto unknown roles in processes that govern metabolic changes during stress responses. Furthermore, a comparative analysis of RBP domain architectures shows both, plant specific and common domain architectures between plants and animals. The latter could be an indication that RBPs are part of an ancient stress response.
This study establishes mRNA interactome capture technique as an approach to study stress signal responses implicated in environmental changes. Our findings denote RBP changes in the proteome as critical components in plant adaptation to changing environments and in particular drought stress protein-dependent changes in RNA metabolism.
RNA 结合蛋白（RBPs）作为转录后基因表达的调控元件，其作用正日益受到重视。RBPs 通过 RNA 结合域与 mRNAs 相互作用，这些相互作用影响翻译过程中 RNA 的可用性、RNA 的稳定性和周转率，从而影响 RNA 和蛋白质的表达，这对于发育和刺激特异性反应至关重要。在这里，我们研究了严重干旱胁迫对 RNA 结合蛋白组的影响，以深入了解在系统水平上调控干旱胁迫反应的机制。
无标记质谱法能够鉴定出 567 种蛋白质，其中 150 种蛋白质对干旱诱导的处理有显著反应。GO 分析显示，在“RNA 结合”和“RNA 处理”类别以及“ABA 响应”和“水分亏缺响应”等生物学过程中富集。重要的是，大量应激响应蛋白以前没有被鉴定为 RBPs，其中包括碳水化合物代谢以及糖酵解和柠檬酸途径中的蛋白质。这表明 RBPs 在调控应激反应过程中代谢变化的未知过程中具有未知的作用。此外，RBP 结构域架构的比较分析显示，植物和动物之间存在植物特异性和常见的结构域架构。后者可能表明 RBPs 是古老的应激反应的一部分。
本研究建立了 mRNA 相互作用组捕获技术，作为研究与环境变化相关的应激信号反应的一种方法。我们的研究结果表明，RBP 在蛋白质组中的变化是植物适应不断变化的环境，特别是干旱胁迫下 RNA 代谢依赖蛋白变化的关键组成部分。
