Structure-Function Relationships of Proteins Which Modulate Platelet Aggregation.

调节血小板聚集的蛋白质的结构-功能关系。

基本信息

批准号：
06454646
负责人：
TITANI Koiti
金额：
$ 4.35万
依托单位：
Fujita Health University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06454646/
关键词：
Platelet adhesion aggregation von Willebrand factor vWF modulator protein GPIb-binding proteins Extracellular matrix Type III collagen フォンビルブラント因子血小板膜糖タンパク質(GP)Ib ボトロセチンジャララカ GPIb-BP アルボアグレギン-B マムシギンビチスセチンジャララカGPIb-BP トカラ

项目摘要

1) Purification, characerization and structure-function relationship of various snake venom proteins modulating platelet adhesion and aggregation : We have already purified and characterized "botrocetin", a von Willebrand factor (vWF) modulating protein, from the snake venom of Bothrops jararaca. In this study, we have isolated and characterized several other proteins with different functions from the same snake venom. These included 'bothrombin' which clots fibrinogen to fibrin, "jararhagin-C" with disintegrin-like activity which inhibits collagen-induced platelet aggregation and "jararaca GPIb-BP" with GPIb-binding activity which inhibits the interaction between vWF and platelets. GPIb-binding proteins have also been isolated from several other snake venoms. Their amino acid sequences have been determined and compared in detail to obtain some insight into the structure-function relationships. We have also isolated a protein with a strong botrocetin-like activity, termed "bitiscetin", … More from the Bitis arietans venom, and determined the amino acid sequence. The sequence homology, however, between botrocetin and bitiscetin is only 45%, suggesting the difference in their interaction mechanisms with vWF.2) Search for physiological vWF modulator : One of monoclonal antibodies raised against botrocetin, BCT-4-3, showed interaction with human endothelial cells and the reactivity was enhanced by addition of fibronectin. Botrocetin-like components immunopurified by immobilized BCT-4-3 from unbilical vein extracts were shown to consist essentially of fibronectin and a 130 kDa molecule. This complex is assumed to mimick botrocetin. 3) Interaction of vWF with extracellular matrix components : Only type III collagen among various extracellular matrix components specifically bound to vWF by an ELISA system. In static conditions, however, the interaction did not induced the interaction of vWF with glycocalicin, the extracellular domain of GPIb containing the vWF binding site, suggesting that another unknown physiological modulator may be involved in the platelet adhesion to extracellular matrix by vWF. Less

1）各种蛇毒蛋白调节血小板广告和聚集的纯化，特征和结构功能关系：我们已经从Bothrops Jararaca的蛇毒液中纯化和表征了Von Willbrand因子（VWF）调节蛋白质的“ Botrocetin”。在这项研究中，我们已经分离并表征了其他几种与同一蛇毒液不同功能不同的蛋白质。其中包括将纤维蛋白原凝结至纤维蛋白的“大凝结蛋白”，具有分解蛋白样活性的“ jararhagin-c”，抑制了胶原蛋白诱导的血小板聚集，而“ jararaca gpib-bp”具有GPIB结合活性，抑制了VWF和血小板之间的相互作用。 GPIB结合蛋白也已从其他几种蛇毒中分离出来。他们的氨基酸序列已被确定并进行了详细比较，以获得对结构功能关系的深入了解。我们还分离了一种具有强肉骨蛋白样活性的蛋白质，称为“ bitiscetin”，……更多来自阿里埃氏毒液的蛋白质，并确定了氨基酸序列。然而，序列同源性在Botrocetin和Bitiscetin之间仅为45％，这表明它们与VWF的相互作用机制的差异。2）搜索物理VWF调节剂：一种针对botrocetin升高的单克隆抗体，BCT-4-3，BCT-4-3，BBCT-4-3，与人类内皮细胞的相互作用相互作用，与反应性增强了反应性。通过固定化的BCT-4-3从非静脉提取物中进行免疫菌株的botrocetin样成分表明，始终如一地表明纤连蛋白基本上是纤连蛋白和130 kDa分子。假定该复合物模拟肉鸡素。 3）VWF与细胞外基质组件的相互作用：仅ELISA系统特异性与VWF结合的各种细胞外基质组件之间仅III型胶原蛋白。然而，在静态条件下，这种相互作用并未诱导VWF与糖蛋白的相互作用，糖果蛋白是含有VWF结合位点的GPIB的细胞外结构域，这表明VWF的血小板粘合物可能与细胞外基质有关。较少的