Regulation of insulin-like growth factors by the ER chaperone GRP94

ER 伴侣 GRP94 对胰岛素样生长因子的调节

基本信息

批准号：
8075480
负责人：
YAIR ARGON
金额：
$ 31.76万
依托单位：
CHILDREN'S HOSP OF PHILADELPHIA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-06-01 至 2014-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8075480
关键词：
ATP phosphohydrolase Affect Anabolism Apoptotic Binding Biochemical Biological Biological Assay Calcium Calcium Binding Cells Chimeric Proteins Client Clinical Co-Immunoprecipitations Code Complement Embryonic Development Endoplasmic Reticulum Essential Amino Acids Family Genes Genetic Polymorphism Genotype Growth Growth Factor Growth Factor Interaction Heat-Shock Proteins 90 Human Hydrolysis Individual Insulin Insulin-Like Growth Factor II Lead Light Maps Measures Mediating Metabolic stress Molecular Molecular Chaperones Molecular Conformation Mutagenesis Mutation Peptides Physiologic pulse Population Production Protein Binding Protein Family Protein Isoforms Proteins Recombinant Proteins Regulation Relaxin Resolution Serum-Free Culture Media Signal Transduction Site Site-Directed Mutagenesis Somatomedins Specificity Structure Surface TLR4 gene Testing Tissues Transfection Variant Work base cell growth embryonic stem cell glucose-regulated protein 94 mutant novel patient population preference programs protein function public health relevance receptor response

ATP phosphohydrolase Affect Anabolism Apoptotic Binding Biochemical Biological Biological Assay Calcium Calcium Binding Cells Chimeric Proteins Client Clinical Co-Immunoprecipitations Code Complement Embryonic Development Endoplasmic Reticulum Essential Amino Acids Family Genes Genetic Polymorphism Genotype Growth Growth Factor Growth Factor Interaction Heat-Shock Proteins 90 Human Hydrolysis Individual Insulin Insulin-Like Growth Factor II Lead Light Maps Measures Mediating Metabolic stress Molecular Molecular Chaperones Molecular Conformation Mutagenesis Mutation Peptides Physiologic pulse Population Production Protein Binding Protein Family Protein Isoforms Proteins Recombinant Proteins Regulation Relaxin Resolution Serum-Free Culture Media Signal Transduction Site Site-Directed Mutagenesis Somatomedins Specificity Structure Surface TLR4 gene Testing Tissues Transfection Variant Work base cell growth embryonic stem cell glucose-regulated protein 94 mutant novel patient population preference programs protein function public health relevance receptor response

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项目摘要

DESCRIPTION (provided by applicant): Insulin-like growth factors (IGFs) mediate differentiation decisions during embryonic development, cell growth signaling and responses to metabolic stress. We found that the production of these important growth factors is dependent on the activity of the endoplasmic reticulum chaperone glucose regulate protein 94 (GRP94), which is essential for their biosynthesis. GRP94 is different from other molecular chaperones in its selectivity towards only a small number of client proteins, preference for late folding intermediates and the absence of any known co-factors. All these aspects suggest a unique mode of action for GRP94. This project will elucidate the enigmatic action cycle of GRP94 by taking advantage of cells whose growth depends on the GRP94-IGF axis. In our first aim we will use a novel cell-based assay to screen for mutants of GRP94 that do not support IGF-II production and thus define amino acids that are essential for this chaperone function. In Aim 2, we will determine whether these mutants are defective in general mechanistic aspects, such as ATP binding and hydrolysis or calcium binding, or whether the mutations define a client binding domain. We will also test the ability of GRP94 mutants to support clients other than IGF, to discover whether there are client-specific mutants. Our third aim is to understand how GRP94 recognizes IGF, by exploiting the structural similarities and differences among a set of insulin-like proteins. These studies will inform on the client selectivity of GRP94, which is currently not understood. Finally, we will take advantage of the clinical consequences of IGF deficiency to search for functionally important human GRP94 variants. Following on our finding that at least one such variant affects IGF production, we will genotype and sequence IGF-deficient patient populations to seek allelic GRP94 variants that may explain low IGF production. Together, these results will lead to a new understanding of how GRP94 chaperones client proteins. PUBLIC HEALTH RELEVANCE: This project aims to decipher how GRP94, representing the family of HSP90 chaperones, selects its client proteins and affects their proper production. The work will use a novel cell-based assay, with insulin-like growth factor as the client, to determine the functionality and characterize biochemically both natural and site-directed mutations in GRP94.

描述（由申请人提供）：胰岛素样生长因子（IGF）介导胚胎发育期间的分化决策，细胞生长信号传导和对代谢应激的反应。我们发现，这些重要生长因子的产生取决于内质网的活性，调节蛋白94（GRP94），这对于它们的生物合成至关重要。 GRP94与其他分子伴侣的选择性仅对少量客户蛋白，偏爱晚期折叠中间体以及没有任何已知的副因素。所有这些方面都暗示了GRP94的独特作用方式。该项目将通过利用生长取决于GRP94-IGF轴的细胞来阐明GRP94的神秘作用周期。在我们的第一个目标中，我们将使用基于细胞的新型测定法来筛选不支持IGF-II产生的GRP94的突变体，从而定义了该伴侣功能所必需的氨基酸。在AIM 2中，我们将确定这些突变体在一般机械方面是否有缺陷，例如ATP结合和水解或钙结合，或该突变是否定义了客户结合域。我们还将测试GRP94突变体支持IGF以外的客户的能力，以发现是否存在客户特异性突变体。我们的第三个目标是通过利用一组胰岛素样蛋白之间的结构相似性和差异来了解GRP94如何识别IGF。这些研究将告知GRP94的客户选择性，目前尚不清楚。最后，我们将利用IGF缺乏症的临床后果来搜索功能重要的人类GRP94变体。在发现至少有一种这种变体会影响IGF产生的情况下，我们将基因型和序列IGF缺陷型患者群体寻求可能解释IGF产生较低的等位基因GRP94变体。这些结果共同将对GRP94伴侣客户蛋白的蛋白质有了新的了解。公共卫生相关性：该项目旨在破译代表HSP90伴侣家族的GRP94如何选择其客户蛋白并影响其适当的生产。这项工作将使用具有胰岛素样生长因子作为客户的新型基于细胞的测定方法，以确定GRP94中自然和定向性突变的功能和表征。