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Basic research on development of anti-thrombus drugs that mimic disintegrins

模拟解整合素抗血栓药物开发的基础研究

基本信息

批准号：
07558218
负责人：
KAWABATA Shun-ichiro
金额：
$ 1.15万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07558218/
关键词：
Disintegrin snake venom Thrombosis

项目摘要

The complete amino acid sequence of ecarin is deduced from the nucleotide sequence of a cDNA clone isolated by screening a venomous gland cDNA library of Kenyan Echis (E).carinatus. The cDNA sequence with 2,379 base pairs encodes an open reading frame of 616 amino acids with a remakeable sequence homology to the putative precursor protein of trigramin from Trimeresurus gramineus venom (61% identity) and a large hemorrhagin, jararhagin, from the pit viper Bothrops jararaca venom (62% identity). Thus, ecarin, as well as jararhagin and trigramin, is translated as a precursor protein, which may be processed posttranslationally. The ecarin proprotein has a "cysteine switch" motif (-Pro-Lys-Met-Cys-Gly-Val-) similar to that involved in the activation of matrix metalloptoteinase zymogens. The processed mature protein consists of 426 amino acid residues (residues 191-616), showing the strongest sequence similarity with that of Russell's viper venom factor X activator (RVV-X) heavy chain (64% identity). Like RVV-X heavy chain, ecarin contains metalloproteinase, disintegrin and cysteine-rich domains. The metalloproteinase domain has a typical zinc chelating sequence (-His-Glu-Xaa-Xaa-His-Xaa-Xaa-Gly-Xaa-Xaa-His-) found in crayfish astacin. In the disintegrin domain of ecarin, the Arg-Gly-Asp sequence is replaced by Arg-Asp-Asp, as found in the disintegrin domains of RVV-X heavy chain (Arg-Asp-Glu) and a guinea pig sperm fusion protein PH-30b (Thr-Asp-Glu). These findings show that while there are the structual and evolutionary relationships among these proteins, each has diverse functional activity.

通过筛选肯尼亚Echis (E).carinatus毒腺cDNA文库，从cDNA克隆的核苷酸序列推导出了ecarin的完整氨基酸序列。该cDNA序列包含2379个碱基，编码616个氨基酸的开放阅读框，序列与Trimeresurus gramineus毒液中推测的trigramin前体蛋白（同源性61%）和Bothrops jararaca毒液中的大出血蛋白jararhagin（同源性62%）具有同源性。因此，ecarin，以及jararhagin和trigramin，被翻译为前体蛋白，可以在翻译后处理。ecarin蛋白具有“半胱氨酸开关”基序（- pro - lys - met - cys - gly - val -），类似于基质金属蛋白酶酶原的激活。经加工的成熟蛋白由426个氨基酸残基组成（残基191 ~ 616），与RVV-X重链序列相似性最强（同源性64%）。与RVV-X重链一样，车毒素含有金属蛋白酶、崩解素和富含半胱氨酸的结构域。小龙虾虾青素金属蛋白酶结构域具有典型的锌螯合序列（- his - glu - xaa - xaa - his - xaa - gli - xaa - xaa - his -）。在ecarin的分解素结构域，Arg-Gly-Asp序列被Arg-Asp-Asp取代，如在RVV-X重链的分解素结构域（Arg-Asp-Glu）和豚鼠精子融合蛋白PH-30b （Thr-Asp-Glu）中发现的。这些发现表明，虽然这些蛋白质之间存在结构和进化关系，但每种蛋白质都具有不同的功能活性。