权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Functional Role of Protein Disulfide Isomerase Isoforms in Platelets

血小板中蛋白质二硫键异构酶亚型的功能作用

基本信息

批准号：
9769101
负责人：
DAVID W ESSEX
金额：
$ 61.35万
依托单位：
TEMPLE UNIV OF THE COMMONWEALTH
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-06-01 至 2022-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9769101
关键词：
Active Sites Affinity Biological Blood Cells Blood Platelets Blood coagulation Cardiovascular Diseases Cellular biology Cleaved cell Clot retraction Coagulation Process Cysteine Defect Deposition Disease Disulfides ERp57 Enzymes Event Family Family member Fibrin Glutathione Disulfide Hemorrhage Human Individual Injury Integral Membrane Protein Integrins Knockout Mice Label Laboratories Lasers Lead Literature Mass Spectrum Analysis Mediating Modeling Molecular Conformation Morbidity - disease rate Mus Myocardial Infarction Oxidation-Reduction Platelet Activation Platelet aggregation Prevention Protein Disulfide Isomerase Protein Isoforms Proteins Receptor Activation Receptor Cell Regulation Reporting Role Signal Transduction Source Stroke Sulfhydryl Compounds Surface Techniques Testing Therapeutic Thrombosis Thrombus United States Work base disulfide bond endoplasmic reticulum glycoprotein p72 extracellular inhibitor/antagonist insight member mortality novel platelet function response

项目摘要

Protein disulfide isomerase (PDI) catalyzes the reversible formation and isomerization of disulfide bonds in proteins, and supports thrombosis. Recent reports indicate that other members of the PDI family, ERp57, ERp5, and ERp72 also contribute to thrombosis. Whether the roles of PDI, ERp57, ERp5 and ERp72 in thrombosis were distinct or redundant was unclear. We showed the aggregation defect in ERp72, PDI or ERp57-null mice was only recovered by the specific PDI that was missing. This implies that these enzymes have individual targets in the activation of the αIIbβ3 platelet integrin that supports platelet aggregation. These PDI family members contain the CGHC active-site motif that catalyzes conformational changes in proteins involved in thrombosis. This proposal focuses on two novel members of the PDI family with this motif that are found in platelets; ERp46, and a transmembrane member of the PDI family, TMX3. We now know that PDI, ERp57, ERp5 and ERp72 mediate platelet aggregation and thrombosis, and are involved in conversion of αIIbβ3 to its high affinity state. However, the actual mechanisms by which these PDIs regulate αIIbβ3 and platelet aggregation are unknown. The individual targets of each enzyme and how they function together remains an enigma. To determine the specific function of each PDI in platelets we have used a targeted knockout mice approach. The specific aims are to: 1. Characterize the role of ERp46 in thrombus formation and platelet function; 2. Characterize the role of TMX3 in thrombus formation and platelet function; and 3. Characterize the cysteine/disulfide targets and mechanism of activation of αIIbβ3 by PDI, ERp57, ERp72, ERp46 and TMX3. A principal technique used will be the laser-induced injury model of thrombosis. To determine the actual mechanisms by which multiple members of the PDI family work together we will employ a thiol labeling strategy with mass spectrometry identification of the labeled thiols. This will begin to unravel the mechanisms by which these enzymes work individually, and how they work together as a network. Elucidation of the extracellular redox network required for the final steps in the activation of αIIbβ3 represents a significant aspect of platelet function and thrombus formation, and can be a model for activation of other integrins. Defining the specific mechanisms could also lead to novel types of inhibitors that dually regulate platelets and coagulation. Since platelets are involved in a variety of disease states, our findings will likely have broader implications for basic understanding of other disease conditions, and possible therapeutic approaches for these conditions.

蛋白质二硫异构酶（PDI）催化蛋白质中二硫键的可逆形成和异构化