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良好平衡 血小板被多种受体激动剂快速激活，并在其中发挥核心作用。 急性冠脉综合征和其他疾病状态下的血栓形成。 抗凝剂对于预防纤维蛋白生成和血栓形成至关重要。二硫化物蛋白的五个成员。 异构酶 (PDI) 家族的酶 PDI、ERp57、ERp5、ERp72 和 ERp46 增强 αIIbα3 和 血栓形成。我们发现了跨膜 PDI 家族成员被发现可抑制 αIIbβ3 的激活和 血小板 PDI 家族成员 TMX1， TMX1 血栓形成。 是第一个 小说中的行为 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 αIIbβ3 构象变化和纤维蛋白原结合的途径 促血栓 PDI 是 由血小板和内皮细胞分泌，支持血管损伤部位纤维蛋白的生成。 发现 TMX1 在血小板和内皮细胞上表达，但是， 消极的 促凝剂 与其他 PDI 相比，TMX1 TMX1 抑制凝血的一种机制是限制纤维蛋白的生成。 我们建议研究内皮细胞和血小板的作用。 t 血管 TMX1 作为双重阴性 通过解决以下具体目标来调节血小板和凝血 我们将描述 1. TMX1在血栓形成中的作用；2.TMX1抑制αIIbβ3激活的机制； TMX1 在其他血小板 PDI 和其他血小板表面基质上的主要技术将是。 我们将研究TMX1阴性的激光诱导的血栓形成损伤模型。 为了确定 TMX1 抑制血小板功能的潜在机制，我们 将整合血小板敲除小鼠模型与基于质谱的功能性鉴定 该提案将确定 TMX1 的工作机制以及 TMX1 的工作原理。 平衡支持 αIIbβ3 激活的 PDI 酶。 TMX1 的作用将为 PDI 酶网络如何调节血栓形成的研究提供新的见解。 TMX1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的最佳方法 止血和抑制血栓形成，为研究TMX1在疾病状态下的作用提供基础。