Molecular Insights into the Mechanism and Regulation of Insulin-Degrading Enzyme

胰岛素降解酶机制和调节的分子洞察

• 批准号: 7758760
• 负责人: Luis Abel Ralat
• 金额: $ 5.05万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7758760
• 关键词: Address; Adopted; Affect; Affinity; Alzheimer' s Disease; Amyloid; Amyloid beta-Protein Precursor; Binding; Carboxypeptidase; Cardiac; Cardiovascular Diseases; Catabolism; Cells; Cleaved cell; Complex; Cultured Cells; Data; Development; Diabetes Mellitus; Disease; Dynorphins; Endorphins; Enkephalins; Enzymes; Exposure to; Family; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Hormones; Human; Hydrogen Peroxide; Hydrolysis; Immunity; In Vitro; Insulin; Insulinase; Kinetics; Laboratories; Leucine Enkephalin; Mediating; Metabolism; Metalloproteases; Modeling; Modification; Molecular; Molecular Conformation; Neprilysin; Neuroblastoma; Neurotransmitters; Non-Insulin-Dependent Diabetes Mellitus; Opioid; Opioid Peptide; Organogenesis; Pain; Peptide Hydrolases; Peptides; Physiological; Post-Translational Protein Processing; Predisposition; Protease Inhibitor; Proteins; Regulation; Relative (related person); Reporting; Research; Risk; Role; Signal Transduction; Site; Site-Directed Mutagenesis; Structure; Therapeutic; Time; X-Ray Crystallography; Zinc; addiction; alanine aminopeptidase; autocrine; base; design; enzyme activity; in vivo; inhibitor/antagonist; insight; member; neurophysiology; novel; overexpression; oxidation; pain behavior; paracrine; peptide I; peptide hormone; public health relevance; success; tool

DESCRIPTION (provided by applicant): Insulin-degrading enzyme (IDE) is a zinc-metalloprotease that is involved in the clearance of insulin and amyloid-p, two key proteins for the development of diabetes and Alzheimer's disease, respectively. Additionally, IDE can bind certain opioid peptides, which function mainly in pain neurophysiology. Protease inhibitors could be used to treat pain because they may increase the lifetime of opioid peptides in vivo and there is a decreased risk for the development of addiction. Furthermore, upon opioid peptide-binding, IDE is selectively activated towards amyloid-p degradation but inhibited towards insulin hydrolysis. However, no crystal structure exists of IDE in complex with any member of the opioid peptide family; thus, I propose to solve the crystal structures of IDE in complex with a representative of each class of opioid peptide, enkephalins, dynorphins, and endorphins. I also plan to characterize the kinetic parameters and the cleavage sites of each opioid peptide by IDE. Moreover, I propose to examine whether IDE can affect the metabolism of opioid peptides and whether it is involved in opioid-mediated signaling in model cultured cells. The characterization of the interaction of opioid peptides with IDE may reveal clues about the conformational changes IDE undergoes upon opioid peptide binding that promote the selective activation toward Ap clearance and may provide a basis for the development of a new class of inhibitors of IDE designed to exclusively catabolize certain peptide substrates. Accumulating evidence strongly suggests that oxidation and nitrosylation are factors involved in the development of diabetes, Alzheimer's disease and cardiovascular disease partially due to post-translational modification of enzymes. In this application, I also propose to assess the vulnerability of IDE to oxidative and nitrosative modification and its effects on enzymatic activity. I will examine whether oxidative/nitrosative inhibition of IDE can occur in cultured neuroblastoma cells, N2a, which overexpress (3-amyloid precursor protein. Site-directed mutagenesis will be used to identify the residues that are modified. I also propose to perform X-ray crystallography to identify the structural implications of IDE inactivation by oxidation and nitrosylation. Success in this aim will define the molecular basis for oxidation and nitrosylation of IDE and may serve as a tool for the design of a therapeutic strategy to reserve IDE activity for the effective clearance of peptides like Ap and insulin. PUBLIC HEALTH RELEVANCE: Insulin-degrading enzyme is considered to be an exciting possible target for treatment of diabetes, Alzheimer's disease and cardiovascular disease. The proposed research may provide an approach to treating these ailments by manipulating the activity of this critical enzyme.

描述（由申请人提供）：胰岛素降解酶（IDE）是一种锌金属蛋白酶，参与胰岛素和淀粉样蛋白-p的清除，这两种蛋白分别是糖尿病和阿尔茨海默病的关键蛋白。此外，IDE可以结合某些主要在疼痛神经生理中起作用的阿片肽。蛋白酶抑制剂可以用于治疗疼痛，因为它们可以增加阿片肽在体内的寿命，并降低成瘾的风险。此外，在阿片肽结合后，IDE选择性地激活淀粉样蛋白-p降解，但抑制胰岛素水解。但是,没有