Contribution of cis-regulatory elements in a plant's response to environmental stress

环境压力，如高温，会对世界上许多作物的生长和产量产生负面影响。植根于地面的植物有独特的策略，可以更好地适应环境的变化，其中很大一部分涉及基因表达的重新编程。基因表达的调控部分是通过转录因子和顺式调控DNA元件之间的复杂相互作用来实现的，顺式调控DNA元件要么位于启动子元件附近，要么距离其靶基因很远。虽然已经确定了许多关键基因来赋予高温耐受性，但许多试图确定与耐受性性状相关的遗传变异的研究已经发现了位于顺式调控元件中的变异。虽然远端顺式调控元件，如增强子，在基因调控中的重要性已在许多真核基因组中显示，但它们对全基因组和逆境特异性转录重编程的影响在植物中仍然很大程度上是未知的。我的研究计划的长期目标是确定远端顺式调控元件对植物应对环境压力的能力的贡献。作为第一步，我将重点介绍一类特定的末端顺式调控元件，即增强子，在主食亚洲水稻(Oryza Sativa)的高温胁迫背景下。与当前提案相关的具体目标包括：1：表征水稻在高温胁迫下增强子的转录活性。2：研究高温胁迫下水稻基因组中不同类型的活性增强子。3：使用计算方法和功能验证确定候选增强子及其靶基因。我的研究计划将描述远端顺式调控DNA元件的作用以及它们与目标基因的相互作用，以了解植物基因组如何在环境胁迫下重新编程基因表达。这些知识将是预测和确定作物改良候选监管目标的关键。事实上，提供对环境胁迫的抵抗力一直是现代育种方法的主要目标，特别是在种植在主要受高温影响的地区的水稻上。这些研究中使用的方法将产生可应用于其他农作物和其他环境压力的生物学洞察力和分析能力。

Environmental stresses, such as high temperature, can negatively impact the growth and yield of many crops in the world. Rooted in the ground, plants have unique strategies for being more resilient to changes in their environment, a major part of which involves the reprograming of gene expression. The control of gene expression is achieved in part by complex interactions between transcription factors and cis-regulatory DNA elements, which are located either adjacent to (promoter elements), or at large distances from (distal regulatory elements) their target genes. While a number of key genes have been identified to confer high temperature tolerance, many studies trying to identify genetic variants associated with tolerance traits have identified variants located within cis-regulatory elements. Whereas the importance of distal cis-regulatory elements, such as enhancers, in gene regulation has been shown in many eukaryotic genomes, their impact on genome-wide and stress-specific transcriptional reprograming remains largely unknown in plants. The long-term objective of my research program is to determine the contribution of distal cis-regulatory elements to a plant's ability to respond to environmental stressors. As a first step, I will focus on a specific class of distal cis-regulatory elements, enhancers, in the context of high temperature stress in the staple food Asian rice (Oryza sativa). The specific objectives associated with the current proposal include: 1: Characterize the transcriptional activity of enhancers in response to high temperature stress in rice. 2: Study the different types of active enhancers in the rice genome under high temperature stress. 3: Identify candidate enhancers and their target genes using computational methods and functional validation. My research program will characterize the roles of distal cis-regulatory DNA elements and their interaction with target genes to understand how plant genomes reprogram gene expression under environmental stress. This knowledge will be key to predict and prioritize candidate regulatory targets for crop improvement. Indeed, providing resistance to environmental stress, has been a major goal of modern breeding approaches, especially in rice which is grown in regions largely impacted by high temperatures. The approaches used in these studies will generate biological insight and analytical capabilities that can be applied to other crop plants and other environmental stresses.