C1 INHIBITOR AND PAI-1--STRUCTURE-FUNCTION STUDIES

纤溶酶原激活物抑制物-1(PAI-1)和C1-抑制物为丝氨酸 蛋白水解酶抑制物(蛇毒蛋白)存在于血浆中，它控制着 纤溶和内源性凝血通路的激活 分别进行了分析。PAI-1过量被认为是一种危险因素 血栓形成和C1-抑制物缺乏会导致血管水肿。蛇类法案 通过机制与靶蛋白水解酶形成稳定的复合体 这些都没有详细明确定义。这个项目的重点是 研究这两种蛇类的结构和功能关系。 目的是进一步阐明丝氨酸的作用机制，以及 确定调节蛇纹蛋白活性的机制。蛋白 以及多肽化学和免疫学技术将被用于 回答四个主要问题：a)结构修改是什么 在C1-抑制剂上观察，当它在其反应部位被切割时，以及如何 这与抑制活性有关吗？；b)分配比是多少 C_1-抑制物和PAI-1与其靶蛋白的反应 受肝素和其他配体的调节，如维生素C？；c) C1-抑制剂和PAI-1上的位点稳定与它们的相互作用 靶标蛋白水解酶，这些相互作用能被用来设计 丝氨酸功能的抑制物？以及d)Vitronectin如何稳定 PAI-1的活性形式及其与PAI-1的结合部位 Vitronectin？这项研究将有助于更好地理解 SERPIN机制，以及对蛋白质降解反应的调节 血栓形成和溶解等过程，以及 治疗干预的可能靶点。

Plasminogen activator inhibitor-1 (PAI-1) and C1-inhibitor are serine proteinase inhibitors (serpins) present in plasma which control the activation of the fibrinolytic and intrinsic coagulation pathways respectively. PAI-1 excess is implicated as a risk factor for thrombosis, and C1-inhibitor deficiency causes angioedema. Serpins act by forming a stable complex with their target proteinase by mechanisms which are not clearly defined in detail. The focus of this project is to study the structurefunction relationships of these two serpins, with the aim of further elucidating the mechanism of serpin action, and identifying mechanisms for the regulation of serpin activity. Protein and peptide chemistry, and immunological techniques will be used to answer four main questions: a) what are the structural modifications observed on C1-inhibitor when it is cleaved at its reactive site, and how does this relate to inhibitory activity?; b) how is the partition ratio for the reaction of C1-inhibitor and PAI-1 with their target proteinases regulated by heparin and other ligands such as vitronectin?; c) which sites on C1-inhibitor and PAI-1 stabilize the interaction with their target proteinases, and can these interactions be used to design inhibitors of serpin function?;. and d) how does vitronectin stabilize the active form of PAI-1 and what are the binding sites on PAI-1 for vitronectin? This research will lead to a better understanding of the serpin mechanism, and the regulation of the proteolytic reactions of processes such as thrombus formation and lysis, as well as indicating possible targets for therapeutic intervention.