MODULATING THE REDUCTIVE UNFOLDING PATHWAY OF RNASE A

调节 RNA酶 A 的还原性解折叠途径

• 批准号: 7369504
• 负责人: HAROLD A. SCHERAGA
• 金额: $ 0.01万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7369504
• 关键词: MODULATING; REDUCTIVE; UNFOLDING; PATHWAY; RNASE

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Reductive unfolding studies of proteins are designed to provide information about intramol. interactions that govern the formation (and stabilization) of the native state and about folding/unfolding pathways. By mutating Tyr92 to G, A, or L in the model protein, bovine pancreatic RNase A, and through analysis of temp. factors and molecular dynamics simulations of the crystal structures of these mutants, it is demonstrated that the markedly different reductive unfolding rates and pathways of RNase A and its structural homolog onconase can be attributed to a single, localized, ring-stacking interaction between Tyr92 and Pro93 in the bovine variant. The fortuitous location of this specific stabilizing interaction in a disulfide-bond-contg. loop region of RNase A results in the localized modulation of protein dynamics that, in turn, enhances the susceptibility of the disulfide bond to redn. leading to an alteration in the reductive unfolding behavior of the homologues. These results have important implications for folding studies involving topol. determinants to obtain folding/unfolding rates and pathways, for protein structure-function prediction through fold recognition, and for predicting proteolytic cleavage sites. Three structures were deposited in the PDB (1YMR, 1YMW, and 1YMN) and the work was published in JACS.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子弹和调查员（PI）可能已经从其他NIH来源获得了主要资金，因此可以在其他清晰的条目中代表。列出的机构适用于该中心，这不一定是调查员的机构。蛋白质的还原性展开研究旨在提供有关内膜内的信息。控制天然状态以及关于折叠/展开途径的形成（和稳定）的相互作用。通过在模型蛋白，牛胰腺RNase A中突变到G，A或L，并通过对温度的分析。这些突变体的晶体结构的因素和分子动力学模拟，证明RNase A及其结构同源性偶生酶的明显不同的还原性展开速率和途径可以归因于牛牛变种中Tyr92和Pro93之间的单个，局部的，环堆叠的相互作用。这种特定的稳定相互作用在二硫键键合中的偶然位置。 RNase A的环区域会导致蛋白质动力学的局部调节，从而增强了二硫键对REDN的敏感性。导致同源物的还原性展开行为发生了变化。这些结果对涉及托波尔的折叠研究具有重要意义。获得折叠/展开速率和途径的决定因素，用于通过折叠识别的蛋白质结构 - 功能预测以及预测蛋白水解裂解位点。三个结构沉积在PDB（1YMR，1YMW和1YMN）中，该工作发表在JACS中。