Diversity Supplement to Structure/Function of Transcription Complex Regulation to Support Predoctoral Student Christiana Binkley

项目摘要/摘要 这个项目的长期目标是定义转录延伸复合体和 通过RNA聚合酶引起和控制暂停和终止的调节器。停顿和过早 终止是原核生物和真核生物基因调控的许多方面，包括转录。 通过染色质和与RNA成熟和翻译的联系。暂停的基本机制都是 和终止以及调节器控制暂停和终止的机制依赖得很差 了解延伸复合体内部相互作用的变化。这些相互作用中的许多都调节了 涉及移动模块的RNA聚合酶的构象变化，包括钳子，触发环，和 血统特定的插入必须达到特定的构象才能有效转录。明白-- 了解调节器如何促进或抑制这些不同的构象将提供必要的关键基础知识 指导抗菌药物或基因治疗调节剂的合理操作。关于以下方面的知识 模型细菌系统也有助于理解高度保守的转录机制 人类。此外，细菌RNA聚合酶是抗生素的已知靶标，而且关于其 功能机制将有助于识别和表征新的抗生素。 将使用结构、生化和遗传方法相结合的方法来表征交互作用。 调节调节的伸长复合体中的片段。低温电子转录检测的新方法 显微镜，用于单分子分析RNA聚合酶与RNA结构、调节剂和 核糖体，并用于基因组规模的分析染色质结构和伸长复合体的调节 发展起来的。这种方法的组合将被用来理解 转录过程中的伸长复合体、细菌染色质的结构、RNA折叠和RNA 翻译。这项工作建立在最近发现的RNA聚合酶协助的结构基础上 RNA折叠，H-NS家族核蛋白细丝在刺激暂停和终止中的作用 在转录沉默期间，以及RNA聚合酶与先锋核糖体的相互作用 被称为表现力的复合体。该项目的具体目标是：(I)阐明暂停、终止-- 以及RNA折叠和关键RNAP模块的作用；(Ii)定义结构、模式和延伸复合体 H-NS家族核蛋白细丝的相互作用；以及(Iii)决定表达体形成的时间和方式 它在转录延伸过程中发挥作用。这一综合研究将有助于建立对TRAN的新理解。 通过定义暂停和终止信号如何改变伸长复杂结构和 动态活性以及染色体结构和翻译偶联如何调节伸长复合体 活动。这些研究的影响将是更好地理解伸长复杂的调节， 广泛应用于生物技术、人类医学以及原核和真核分子生物学。

Project Summary/Abstract The long-term goal of this project is to define the interactions within transcription elongation complexes and with regulators that cause and control pausing and termination by RNA polymerase. Pausing and premature termination underlie many aspects of gene regulation in prokaryotes and eukaryotes, including transcription through chromatin and linkages to RNA maturation and translation. Both the basic mechanisms of pausing and termination and the mechanisms by which regulators control pausing and termination depend on poorly understood changes to interactions within the elongation complex. Many of these interactions modulate conformational changes in RNA polymerase involving mobile modules including the clamp, trigger loop, and lineage-specific insertions that must achieve particular conformations for efficient transcription. Understand- ing how regulators promote or inhibit these different conformations will provide key basic knowledge essential to guide the rational manipulation of regulators for antimicrobials or gene therapies. Knowledge gained about model bacterial systems also facilitates understanding of highly conserved mechanisms of transcription in humans. Additionally, bacterial RNA polymerase is a known target of antibiotics, and knowledge about its functional mechanisms will aid in identifying and characterizing new antibiotics. A combination of structural, biochemical, and genetic approaches will be used to characterize the interac- tions in the elongation complex that mediate regulation. New methods for transcription assay by cryo-electron microscopy, for single-molecule assay of RNA polymerase interactions with RNA structures, regulators, and ribosomes, and for genome-scale analysis of chromatin structure and elongation complex regulation will be developed. This combination of approaches will be used to understand connections among progress of the elongation complex during transcription, the structure of bacterial chromatin, RNA folding, and RNA translation. The work builds on recent discoveries of the structural basis by which RNA polymerase assists RNA folding, of the role of H-NS family nucleoprotein filaments in stimulation of pausing and termination during transcriptional silencing, and of interaction of RNA polymerase with the pioneering ribosome in a complex called the expressome. The specific aims of the project are to (i) elucidate steps in pausing, termina- tion, and RNA folding and roles of key RNAP modules; (ii) define structures, patterns, and elongation complex interactions of H-NS family nucleoprotein filaments; and (iii) determine when the expressome forms and how it functions during transcript elongation. This integrated research will help build a new understanding of tran- scriptional regulation by defining how pause and termination signals change elongation complex structure and activity dynamically and how chromosome structure and translational coupling modulate elongation complex activity. The impact of these studies will be an improved understanding of elongation complex regulation, with broad applications to biotechnology, human medicine, and both prokaryotic and eukaryotic molecular biology.