PDF(Pubmed)
Abstract：
During inflammation and situations of cellular stress protein disulfide isomerase (PDI) is released in the blood plasma from the platelet and endothelial cells to influence thrombosis. The addition of exogenous PDI makes the environment pro-thrombotic by inducing disulfide bond formation in specific plasma protein targets like vitronectin, factor V, and factor XI. However, the mechanistic details of PDI interaction with its target remain largely unknown. A decrease in the coagulation time was detected in activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) on addition of the purified recombinant PDI (175 nM). The coagulation time can be controlled using an activator (quercetin penta sulfate, QPS) or an inhibitor (quercetin 3-rutinoside, Q3R) of PDI activity. Likewise, the PDI variants that increase the PDI activity (H399R) decrease, and the variant with low activity (C53A) increases the blood coagulation time. An SDS-PAGE and Western blot analysis showed that the PDI does not form a stable complex with either thrombin or antithrombin (ATIII) but it uses the ATIII-thrombin complex as a template to bind and maintain its activity. A complete inhibition of thrombin activity on the formation of ATIII-thrombin-PDI complex, and the complex-bound PDI-catalyzed disulfide bond formation of the target proteins may control the pro- and anti-thrombotic role of PDI.
摘要：
在炎症和细胞应激的情况下,蛋白质二硫化物异构酶(PDI)在血浆中从血小板和内皮细胞释放以影响血栓形成。外源性PDI的添加通过在特定的血浆蛋白靶标如玻连蛋白中诱导二硫键形成而使环境促血栓形成,因子V,和因素XI。然而,PDI与其靶标相互作用的机制细节在很大程度上仍然未知.在活化部分凝血活酶时间（APTT）中检测到凝血时间的减少，凝血酶原时间（PT），和凝血酶时间（TT）除了纯化的重组PDI（175nM）。可以使用活化剂（硫酸槲皮素，QPS）或抑制剂（槲皮素3-菊酯苷，PDI活性的Q3R)。同样，增加PDI活性的PDI变体（H399R）减少，并且具有低活性的变体(C53A)增加血液凝固时间。SDS-PAGE和western印迹分析显示,PDI不与凝血酶或抗凝血酶(ATIII)形成稳定的复合物,而是使用ATIII-凝血酶复合物作为模板结合并保持其活性。凝血酶活性完全抑制ATIII-凝血酶-PDI复合物的形成，以及靶蛋白的复合物结合PDI催化的二硫键形成可能控制PDI的促血栓和抗血栓形成作用。
