Regulation of Aberrant Protein Production

异常蛋白质生产的调节

基本信息

批准号：
10248453
负责人：
Andrey L Karamyshev
金额：
$ 30.6万
依托单位：
TEXAS TECH UNIVERSITY HEALTH SCIS CENTER
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-09-16 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10248453
关键词：
Address Cells Complex Defect Detection Disease Enzymes Genetic Transcription Hormones Human Immunofluorescence Immunologic In Vitro Knowledge Lead Mammalian Cell Mass Spectrum Analysis Mediating Membrane Proteins Messenger RNA Modeling Molecular Monitor Mutation Northern Blotting Pathway interactions Peptide Signal Sequences Process Production Prolactin Proteins Quality Control Regulation Research Ribosomes Signal Recognition Particle Site Stress System Technology Testing Translational Repression Translations Ubiquitin Western Blotting crosslink design endonuclease human disease in vivo knock-down mRNA Transcript Degradation misfolded protein multicatalytic endopeptidase complex novel overexpression polypeptide polysome profiling prevent protein aggregation protein expression response secretory protein sensor transcriptome transcriptome sequencing

项目摘要

ABSTRACT Defective proteins result from mutations, mistakes of transcription, stress, and other factors. These aberrant proteins are often toxic and cause a number of human diseases. There are several quality control (QC) pathways in the cells: nonsense-mediated, no-stop, and no-go decays for defective mRNAs, and the ubiquitin/proteasome system for already synthesized misfolded proteins. Recently, we discovered a new QC pathway called Regulation of Aberrant Protein Production (RAPP). RAPP is a preemptive QC, it monitors proteins during their synthesis at the ribosome, senses defective proteins and degrades their mRNA templates. It is the first example of transferring information about aberrant proteins to mRNA degradation machinery. Normally, nascent polypeptides emerged from the ribosome exit tunnel interact with targeting or folding factors. When a mutation prevents these interactions, the Ago2 protein, a sensor in the RAPP response, detects the loss of these important interactions and triggers mRNA degradation. Surprisingly, Ago2 endonuclease activity is not required in the process. Thus, the molecular mechanism of RAPP is not well understood, very little is known about its mRNA degradation machinery and its substrates. The proposed project will fill these gaps in knowledge. Our hypothesis is that RAPP is a general protein quality control pathway that consists of three major steps: detection of an aberrant nascent chain complex, translational repression, and formation of specialized cytoplasmic foci for degradation of the aberrant mRNA. Our specific aims are designed to test this hypothesis and directed to (1) elucidate the mechanism by which protein expression is down-regulated in RAPP, and (2) determine whether RAPP is a general mechanism of protein quality control for secretory and membrane proteins in mammalian cells. The proposal involves application of comprehensive in vivo and in vitro approaches, including our unique technology, iPINCH, for identification of Proteins Interacting with Nascent Chains. Determining the scope and mechanism of RAPP will impact the field of protein quality control research by providing a better understanding of cellular defense against erroneous and potentially toxic proteins.

抽象的有缺陷的蛋白质是由突变、转录错误、压力和其他因素造成的。这些异常的蛋白质通常有毒，会导致许多人类疾病。有几个质量控制（QC）细胞中的通路：有缺陷的 mRNA 的无义介导的、不停歇和不停歇的衰变，以及用于已经合成的错误折叠蛋白质的泛素/蛋白酶体系统。最近，我们发现了一个新的QC 称为异常蛋白质生产调节（RAPP）的途径。 RAPP 是一个抢占式 QC，它监控蛋白质在核糖体合成过程中，感知有缺陷的蛋白质并降解其 mRNA 模板。这是将异常蛋白质信息转移到 mRNA 降解机制的第一个例子。通常，从核糖体出口通道出现的新生多肽与靶向或折叠因子相互作用。当突变阻止这些相互作用时，Ago2 蛋白（RAPP 反应中的传感器）会检测到失去这些重要的相互作用并引发 mRNA 降解。令人惊讶的是，Ago2 核酸内切酶活性过程中不需要。因此，RAPP的分子机制尚不清楚，知之甚少。了解其 mRNA 降解机制及其底物。拟议的项目将填补这些空白知识。我们的假设是 RAPP 是一种通用的蛋白质质量控制途径，由三个组成主要步骤：异常新生链复合物的检测、翻译抑制以及形成用于降解异常 mRNA 的专门细胞质焦点。我们的具体目标旨在测试这一点假设并旨在（1）阐明蛋白质表达下调的机制 RAPP，以及（2）确定 RAPP 是否是分泌和蛋白质质量控制的通用机制。哺乳动物细胞中的膜蛋白。该提案涉及体内和体内综合应用体外方法，包括我们独特的技术 iPINCH，用于鉴定与新生链。确定RAPP的范围和机制将影响蛋白质质量控制领域通过更好地了解细胞防御错误和潜在毒性的研究蛋白质。