The Transmembrane Protein Disulfide Isomerase TMX1 Negatively Regulates Thrombosis

跨膜蛋白二硫键异构酶 TMX1 负向调节血栓形成

• 批准号: 10586515
• 负责人: DAVID W ESSEX
• 金额: $ 71.45万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-15 至 2026-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10586515
• 关键词: Address; Agonist; Antibodies; Anticoagulants; Binding; Blood Cells; Blood Platelets; Blood Vessels; Blood coagulation; COVID-19; Clot retraction; Coagulation Process; Cysteine; Disease; ERp57; Endothelial Cells; Endothelium; Enzymes; Equilibrium; Event; Extracellular Protein; Family; Fibrin; Fibrinogen; Generations; Hemorrhage; Hemostatic function; Human; Immune checkpoint inhibitor; Injury; Integral Membrane Protein; Integrins; Isomerism; Knockout Mice; Lasers; Mass Spectrum Analysis; Mediating; Membrane; Modeling; Molecular Conformation; Morbidity - disease rate; Mus; Myocardial Infarction; Pathway interactions; Phosphatidylserines; Platelet Activation; Platelet Aggregation Inhibition; Platelet aggregation; Protein Disulfide Isomerase; Proteins; Recombinants; Regulation; Role; Signal Transduction; Site; Stroke; Sulfhydryl Compounds; Surface; Techniques; Thrombosis; Thrombus; United States; Vascular System; Wild Type Mouse; Work; acute coronary syndrome; disulfide bond; disulfide bond reduction; endoplasmic reticulum glycoprotein p72; extracellular; in vivo; insight; member; mortality; mouse model; novel; oxidation; platelet function; prevent; receptor; translocase; vascular injury

The control of platelet function and coagulation is a fine balance between activation and inhibitory mechanisms. Platelets become rapidly activated by multiple receptors agonists and have a central role in thrombosis in acute coronary syndromes, and other disease states. Similarly, naturally occurring anticoagulants are critical in preventing fibrin generation and thrombosis. Fivemembers of theprotein disulfide isomerase (PDI) family of enzymes, PDI, ERp57, ERp5, ERp72 and ERp46 potentiate activation of IIb3 and thrombosis.We discovered atransmembrane member of the PDI family found to inhibit activation of IIb3 and member of the PDI family in platelets, TMX1, which thrombosis. TMX1 is the first acts by a novel mechanism of oxidizing thiols to disulfide bonds and is the last checkpoint inhibitor of the platelet activation pathways that lead to conformational changes in IIb3 and fibrinogen binding. The prothrombotic PDIs are secreted from platelets and endothelial cells and support fibrin generation at the site of vascular injury. We found that TMX1 is expressed on platelets and endothelial cells but, negatively procoagulant in contras to the other PDIs, TMX1 regulates fibrin generation. One mechanism by which TMX1 inhibits coagulation is by limiting the effect of endothelial cells and platelets. We propose to study t vascular TMX1 as a dual negative regulator of platelets and coagulation by addressing the following Specific Aims. We will characterize 1. the role of TMX1 in thrombus formation; 2. the mechanism of inhibition of IIb3 activation by TMX1; 3. the effect of TMX1 on the other platelet PDIs, and on other platelet surface substrates. A principal technique used will be the laser-induced injury model of thrombosis. We will study the mechanism by which TMX1 negatively regulates coagulation. To determine the underlying mechanisms by which TMX1 inhibits platelet function we will integrate a platelet knockout mouse model with mass spectrometry-based identification of functional cysteines. This proposal will determine the mechanisms by which TMX1 works, and how TMX1 counterbalances the PDI enzymes that support activation of IIb3. Characterization of the negative regulatory role of TMX1 will provide novel insight into how the network of PDI enzymes regulate thrombosis. Studies on how TMX1 maintains the balance between thrombosis and hemostasis will elucidate optimal ways to promote hemostasis and inhibit thrombosis and provide a basis for studying TMX1 in disease states.

血小板功能和凝血的控制是激活和抑制之间的精细平衡 机制等血小板可被多种受体激动剂迅速激活，并在细胞凋亡中发挥核心作用。 急性冠状动脉综合征和其他疾病状态中的血栓形成。同样，自然发生的 抗凝血剂在防止纤维蛋白生成和血栓形成中是关键的。蛋白质二硫化物的五个成员 异构酶（PDI）家族的酶，PDI、ERp 57、ERp 5、ERp 72和ERp 46增强了β IIb β 3的活化， 血栓形成。我们发现了一种跨膜 PDI家族成员，发现可抑制β IIb β 3的活化， 血小板中PDI家族的成员TMX 1， 血栓形成TMX1 是第一 小说剧本 将硫醇氧化为二硫键的机制，是血小板活化的最后一个检查点抑制剂 导致β IIb β 3和纤维蛋白原结合的构象变化的途径。血栓前PDI是 由血小板和内皮细胞分泌并支持血管损伤部位的纤维蛋白生成。我们 发现TMX 1在血小板和内皮细胞上表达， 负 促凝血 与其他PDI相比，TMX 1 调节纤维蛋白生成。TMX 1抑制凝血的一种机制是通过限制 内皮细胞和血小板的作用。我们建议研究 不 血管TMX 1为双阴性 血小板和凝血调节剂，解决以下具体目标。我们将描述1。的 TMX 1在血栓形成中的作用; 2. TMX 1抑制β IIb β 3活化的机制; 3.效果 TMX 1在其他血小板PDI上和其他血小板表面基质上的表达。使用的主要技术将是 激光诱导血栓形成的损伤模型。我们将研究TMX 1负性作用于 调节凝血。为了确定TMX 1抑制血小板功能的潜在机制， 将整合血小板敲除小鼠模型与基于质谱的功能鉴定， 半胱氨酸。该提案将确定TMX 1的工作机制，以及TMX 1 平衡支持β IIb β 3活化的PDI酶。负调控的表征 TMX 1的作用将为PDI酶网络如何调节血栓形成提供新的见解。研究 TMX 1如何维持血栓形成和止血之间的平衡将阐明促进血栓形成和止血的最佳途径。 为研究TMX 1在疾病状态下作用提供了基础。