Protein Folding in the Eukaryotic Cytosol

描述（由申请人提供）：本研究计划的长期目标是了解新翻译的蛋白质如何在真核细胞中折叠。拟议的研究将集中在折叠事件，因为它们发生在核糖体在多肽合成过程中，并将检查分子伴侣在其折叠过程中的作用。理解从头蛋白质折叠的概念框架源于我们在上一个资助周期中的工作，该工作表明名为CLIPS（与蛋白质合成相关的伴侣蛋白）的伴侣蛋白网络在物理和功能上与翻译机制相关。我们的工作假设是CLIPS分子伴侣的任务是引导新合成的多肽折叠构象。分子伴侣介导的折叠途径似乎涉及不同类别的CLIPS的合作，包括在折叠过程早期起作用的分子伴侣，如新生链相关复合物（NAC）、Hsp 70蛋白和GIM/前折叠素复合物，以及在折叠过程后期起作用的机械上不同的分子伴侣TRiC/CCT和Hsp 90。我们的一般策略，以阐明如何伴侣介导的新合成的蛋白质的折叠依赖于在体外和体内方法的紧密结合。我们提出的实验的目的是获得功能，机械和结构的见解分子伴侣从头折叠的作用。

DESCRIPTION (provided by applicant): The long term goal of this Research Program is to understand how newly translated proteins fold in eukaryotic cells. The proposed research will focus on folding events as they occur at the ribosome during synthesis of a polypeptide and will examine the role of molecular chaperones in their folding process. The conceptual framework for understanding de novo protein folding originates from our work in the previous funding cycle, which showed that a network of chaperones named CLIPS (Chaperones Linked to Protein Synthesis) is physically and functionally linked to the translation machinery. Our working hypothesis is that the CLIPS chaperones are tasked with guiding newly synthesized polypeptides to their folded conformation. Chaperone-mediated folding pathways appear to involve the cooperation of different classes of CLIPS, including chaperones that act early in the folding process, such as the Nascent Chain Associated Complex (NAC), the Hsp70 proteins and the GIM/prefoldin complex, and the mechanistically distinct chaperones TRiC/CCT and Hsp90, which appear to act later in the folding process. Our general strategy to elucidate how chaperones mediate the folding of newly synthesized proteins relies on the close integration of in vitro and in vivo approaches. Our proposed experiments are aimed at obtaining functional, mechanistic and structural insights into the role of chaperones in de novo folding.