CONFORMATION OF HSP70-BOUND PEPTIDE SUBSTRATES PROBED USING NMR SPECTROSCOPY

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 Hsp 70分子伴侣系统是一个广泛存在的蛋白质家族，参与多种重要的细胞过程，如蛋白质稳态、应激反应和膜转位。底物通过Hsp 70的重折叠通过未折叠的多肽底物与DnaK（大肠杆菌Hsp 70）以及辅伴侣DnaJ和GrpE在复杂的ATP依赖性伴侣循环中的相互作用而发生。然而，人们对底物重新折叠至其天然状态的分子机制知之甚少。这项工作的目标是探测热休克蛋白70结合的多肽底物的构象在高分辨率使用NMR光谱。特别是，我们研究了核苷酸诱导的变化的骨架构象的肽底物使用Ca和C'二级化学位移作为残留物特异性探针的二级结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Hsp70 chaperone system is ubiquitous family of proteins involved in a variety of critical cellular processes such as protein homeostasis, stress response and membrane translocation. Substrate refolding by Hsp70 occurs through the interaction of unfolded polypeptide substrates with DnaK (the E.coli Hsp70), as well as cochaperones DnaJ and GrpE, in a complex ATP-dependent chaperone cycle. However, the molecular mechanism by which substrates are refolded to their native state is poorly understood. The goal of this work is to probe the conformation of Hsp70-bound polypeptide substrates at high resolution using NMR spectroscopy. In particular, we study the nucleotide-induced changes in the backbone conformation of peptide substrates using Ca and C' secondary chemical shifts as residue-specific probes of secondary structure.