Molecular Basis of Blood Coagulation Regulation

凝血调节的分子基础

基本信息

批准号：
7819176
负责人：
Steven T. Olson
金额：
$ 0.72万
依托单位：
UNIVERSITY OF ILLINOIS AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-06-08 至 2009-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7819176
关键词：
Affect Amino Acids Angiogenesis Inhibitors Anticoagulants Antithrombin III Antithrombins Autolysis Binding Binding Sites Blood Clot Blood Proteins Blood coagulation Burial Cleaved cell Coagulation Process Complex Docking Elements Endothelial Cells Engineering Epitopes Event Factor IXa Factor Xa Family Generations Glycosaminoglycans Goals Heating Hemostatic function Heparan Sulfate Proteoglycan Heparin Heparin Binding Heparitin Sulfate Inorganic Sulfates Length Link Malignant Neoplasms Maps Mediating Molecular Molecular Conformation Peptide Hydrolases Physiological Protease Inhibitor Proteolysis Reaction Regulation Role S cerevisiae SWI3 protein Series Serpins Signal Transduction Site Specificity Structure Testing Unspecified or Sulfate Ion Sulfates Vertebrates antitumor drug base beta pleated sheet cardiovascular disorder prevention design improved mimetics novel receptor

项目摘要

The serpin family coagulation protease inhibitor, antithrombin and its glycosaminoglycan activators, heparin and heparan sulfate, comprise a key anticoagulant mechanism which is essential for maintaining hemostasis in vertebrates. Intriguingly, antithrombin has been recently shown to possess antiangiogenic and antitumor functions whose physiologic role remains to be determined. To advance our long-term goal of elucidating the molecular mechanisms by which antithrombin carries out its physiologically relevant functions, we propose to pursue three specific aims: 1) We have previously shown that the molecular determinants which mediate the specificity of heparin-activated antithrombin for blood clotting proteases reside both in an exposed reactive center loop of the serpin and in exosite regions outside the loop. We propose to map these exosite regions on antithrombin and on factor Xa and factor IXa and determine the mechanism by which the exosites mediate heparin rate enhancement of antithrombin reactions with the proteases; 2) Antithrombin circulates in an unusual low-activity conformation in which the reactive loop is partially buried in beta-sheet A, but is induced by heparin into a high-activity conformation resembling that of other serpins in which the reactive loop is expelled from the sheet. We propose to identify the molecular determinants of this reactive loop conformational switch and delineate the sequence of molecular events in the heparin binding site which trigger the conformational switch; 3) Antithrombin expresses a potent antiangiogenic activity when it undergoes conformational changes which occur spontaneously or are induced by cleavage in the reactive loop and which result in the burial of the reactive loop into beta-sheet A. We will determine the structural basis for the antiangiogenic activity of cleaved, latent and a novel prelatent form of antithrombin. The role of specific endothelial cell binding sites in this activity and whether these binding sites involve a protein receptor and/or specific domains of a heparan sulfate proteoglycan will be determined. The proposed studies are expected to provide increased understanding at the molecular level of the function of a key natural anticoagulant and antiangiogenic blood protein. This understanding is expected to facilitate the rational design of a new generation of anticoagulant and antitumor drugs for the treatment and prevention of cardiovascular diseases and cancer.

丝氨酸蛋白酶抑制剂家族凝血蛋白酶抑制剂、抗凝血酶及其糖胺聚糖激活剂、肝素和硫酸乙酰肝素，构成了维持止血所必需的关键抗凝机制在脊椎动物中。有趣的是，抗凝血酶最近被证明具有抗血管生成和抗肿瘤作用其生理作用仍有待确定的功能。为了推进我们阐明问题的长期目标抗凝血酶发挥其生理相关功能的分子机制，我们建议追求三个具体目标：1）我们之前已经表明，介导肝素激活的抗凝血酶对凝血蛋白酶的特异性存在于暴露的反应性丝氨酸蛋白酶抑制剂的中心环和环外的外位点区域。我们建议绘制这些外部区域的地图抗凝血酶以及因子 Xa 和因子 IXa 的作用，并确定外部位点的机制介导肝素与蛋白酶抗凝血酶反应的速率增强； 2) 抗凝血酶在体内循环一种不寻常的低活性构象，其中反应环部分埋藏在 β-折叠片 A 中，但由肝素诱导形成类似于其他丝氨酸蛋白酶抑制剂的高活性构象，其中反应性环从纸张中排出。我们建议确定该反应环的分子决定因素构象转换并描绘肝素结合位点中分子事件的序列触发构象开关； 3) 抗凝血酶表现出有效的抗血管生成活性经历自发发生或由反应性裂解诱导的构象变化环并导致反应环被埋入β-片层A中。我们将确定结构裂解、潜伏和新型前潜伏形式抗凝血酶的抗血管生成活性的基础。的作用该活动中的特定内皮细胞结合位点以及这些结合位点是否涉及蛋白质受体和/或硫酸乙酰肝素蛋白聚糖的特定结构域将被确定。拟议的研究是有望在分子水平上加深对关键天然物质功能的理解抗凝和抗血管生成血液蛋白。这种理解有望促进理性设计新一代抗凝和抗肿瘤药物，用于治疗和预防心血管疾病和癌症。

项目成果

期刊论文数量（76）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Importance of tryptophan 49 of antithrombin in heparin binding and conformational activation.

抗凝血酶色氨酸 49 在肝素结合和构象激活中的重要性。

DOI：
10.1021/bi050741i
发表时间：
2005
期刊：
Biochemistry
影响因子：
2.9
作者：
Monien,BernhardH;Krishnasamy,Chandravel;Olson,StevenT;Desai,UmeshR
通讯作者：
Desai,UmeshR

Antiangiogenic forms of antithrombin specifically bind to the anticoagulant heparin sequence.

DOI：
10.1021/bi801656u
发表时间：
2008-12-23
期刊：
Biochemistry
影响因子：
2.9
作者：
Schedin-Weiss S;Richard B;Hjelm R;Olson ST
通讯作者：
Olson ST

Decreased affinity of recombinant antithrombin for heparin due to increased glycosylation.

由于糖基化增加，重组抗凝血酶与肝素的亲和力降低。

DOI：
10.1042/bj2860793
发表时间：
1992
期刊：
The Biochemical journal
影响因子：
0
作者：
Björk,I;Ylinenjärvi,K;Olson,ST;Hermentin,P;Conradt,HS;Zettlmeissl,G
通讯作者：
Zettlmeissl,G

Immunologic evidence for insertion of the reactive-bond loop of antithrombin into the A beta-sheet of the inhibitor during trapping of target proteinases.

在捕获目标蛋白酶期间，抗凝血酶的反应键环插入抑制剂的 Aβ-片层的免疫学证据。

DOI：
10.1021/bi00077a002
发表时间：
1993
期刊：
Biochemistry
影响因子：
2.9
作者：
Björk,I;Nordling,K;Olson,ST
通讯作者：
Olson,ST

Mechanism by which exosites promote the inhibition of blood coagulation proteases by heparin-activated antithrombin.

外泌体促进肝素激活抗凝血酶抑制凝血蛋白酶的机制。

DOI：
10.1074/jbc.m702462200
发表时间：
2007
期刊：
The Journal of biological chemistry
影响因子：
0
作者：
Izaguirre,Gonzalo;Swanson,Richard;Raja,SrikumarM;Rezaie,AlirezaR;Olson,StevenT
通讯作者：
Olson,StevenT