MOLECULAR MECHANISM OF THROMBIN INHIBITION

凝血酶抑制的分子机制

• 批准号: 2031426
• 负责人: SCOTT T COOPER
• 金额: $ 9.29万
• 依托单位: UNIVERSITY OF WISCONSIN LA CROSSE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2031426
• 关键词: antithrombins; blood coagulation; molecular biology; protease inhibitor; protein C; protein sequence; serine proteinases; thrombin; thrombomodulin

DESCRIPTION (Adapted from investigator's abstract): The regulation of coagulation is central to many diseases, including heart disease and stroke. The objective of this research is to better understand the different mechanisms by which the serpins antithrombin (AT) and protein C inhibitor (PCI) inhibit free thrombin, and thrombin bound to thrombomodulin (TM). Specifically, the role of the reactive site loop of PCI in the inhibition of thrombin bound to TM will be examined. A second objective will be to compare the function of the H-helix of PCI with the H-helix of AT. The first aim of this proposal is to substitute the P3-P3' reactive site loop residues of PCI for those of AT to determine whether the high rates of inactivation are due merely to the reactive site loop differences, or some other portion of PCI. The second aim is to determine the role of the H-helix in AT. To do this, glutamate residues in the H-helix of AT will be replaced with arginine and lysine, mimicking the structure of the H-helix in PCI. In the third aim, position 314 of AT will be mutated to an arginine. These proteins will then be assayed with thrombin in the presence and absence of TM to determine whether these mutations alter the activity of AT. The outcome of these experiments may provide a clearer understanding of the different mechanisms by which PCI and AT inhibit thrombin complexed with TM.

描述（改编自研究者摘要）： 凝血是许多疾病的核心，包括心脏病和中风。 这项研究的目的是为了更好地了解不同的 丝氨酸蛋白酶抑制剂抗凝血酶（AT）和蛋白C抑制剂 (PCI)抑制游离凝血酶和与血栓调节蛋白（TM）结合凝血酶。 具体而言，PCI的反应位点环在抑制 将检查与TM结合的凝血酶。 第二个目标是 比较PCI和AT的H螺旋的功能。 的 该建议的第一个目的是用P3-P3'反应位点环取代P3-P3'反应位点环 PCI的残留物对AT的残留物进行比较，以确定 失活仅仅是由于反应位点环的差异，或一些 PCI的另一部分。 第二个目标是确定 AT中的H-螺旋。 为此，AT的H-螺旋中的谷氨酸残基将被 用精氨酸和赖氨酸取代，模拟了 PCI。 在第三个目标中，AT的314位将突变为精氨酸。 然后在存在凝血酶的情况下用凝血酶测定这些蛋白质， 不存在TM以确定这些突变是否改变AT的活性。 这些实验的结果可能会提供一个更清晰的理解， PCI和AT抑制与TM复合的凝血酶的不同机制。