Structural and Functional Studies of Mtr4 and Mtr4-mediated Complexes

Mtr4 和 Mtr4 介导的复合物的结构和功能研究

• 批准号: 9009671
• 负责人: SEAN J JOHNSON
• 金额: $ 25.03万
• 依托单位: UTAH STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-30 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9009671
• 关键词: Address; Biochemical; Cell Nucleus; Cell physiology; Characteristics; Complex; Cytosol; Disease; Event; Excision; In Vitro; Individual; Lead; Link; Malignant Neoplasms; Mediating; Modeling; Molecular; Mutation; Neurodegenerative Disorders; Nuclear; Pathway interactions; Phosphodiesterase I; Play; Process; Protein Binding; Protein Subunits; Proteins; RNA; RNA Degradation; RNA Helicase; RNA Processing; Role; Structure; Substrate Interaction; Substrate Specificity; System; base; endonuclease; genetic analysis; helicase; in vivo; novel; prevent; public health relevance; research study

 DESCRIPTION (provided by applicant) The integrity and availability of cellular RNA is tightly regulated by a variety of RNA processing, turnover, and surveillance pathways. The eukaryotic exosome plays a major role in the processing and degradation of a wide variety of RNAs in both the nucleus and cytosol. Several protein factors associate with the exosome to identify appropriate RNA substrates and activate exosome activity. A major challenge is to understand the molecular details of how these proteins interact with RNA substrates and with each other to achieve substrate specificity. Notably, the only protein factor that is required for all known activities of the nuclear exosome i the RNA helicase, Mtr4. Given this central role in exosome activation, there is a critical need to understand how Mtr4 functions, how it interacts with RNA substrates, and how it mediates and is influenced by assembly of other exosome activating factors. Recent studies indicate that the arch domain of Mtr4 plays a previously unrecognized role in unwinding RNA substrates. The underlying basis for this observation is unclear, but is proposed to be a function of substrate interactions that connect the arch to the core helicase domains. The detailed interactions between Mtr4 and other complexes, such as the TRAMP complex, are also poorly understood. This project seeks to define the molecular basis for Mtr4 function by employing a variety of biochemical and structural approaches, combined with in vivo genetic analysis. The specific aims of this project are to (1) describe the role of the arch domain in RNA recognition and unwinding, and (2) characterize Mtr4 interactions with protein binding partners.

 描述（由申请人提供） 细胞RNA的完整性和可用性受多种RNA处理的严格调节， 营业额和监视途径。真核外泌体在核和细胞质中各种RNA的加工和降解中起主要作用。几种蛋白质因子与外泌体相关，以鉴定适当的RNA底物并激活外泌体活性。一个主要的挑战是了解这些蛋白质如何与RNA底物相互作用以及彼此之间的分子细节以实现底物特异性。值得注意的是，核外泌体I（RNA解旋酶MTR4）所有已知活性所需的唯一蛋白质因子。鉴于这种核心在外泌体激活中的作用，需要了解MTR4的功能，与RNA底物的相互作用以及它如何介导和受其他外泌体激活因子的组装影响。最近的研究表明，MTR4的拱形结构域在放松RNA底物中起着先前未知的作用。该观察结果的基础尚不清楚，但被认为是将拱形连接到核心愈合域的底物相互作用的函数。 MTR4与其他复合物（例如流浪汉复合物）之间的详细相互作用也很熟悉。该项目旨在通过采用多种生化和结构方法以及体内遗传分析来定义MTR4功能的分子基础。该项目的具体目的是（1）描述Arch域在RNA识别和放松中的作用，以及（2）表征MTR4与蛋白质结合伙伴的相互作用。