Bruton's tyrosine kinase is a substrate of calpain in human platelets.
Bruton's tyrosine kinase is a substrate of calpain in human platelets.
复制标题
布鲁顿酪氨酸激酶是人血小板中钙蛋白酶的底物。
DOI：
10.1016/s0014-5793(01)02765-x
复制
发表时间：
2001
期刊：
影响因子：
3.5
通讯作者：
Dash,D
中科院分区：
文献类型：
--
作者：
Mukhopadhyay,S;Ramars,AS;Ochs,HD;Dash,D
用钙离子载体A23187处理后，血小板相关的Bruton‘s酪氨酸激酶(BTK)被完全切割，出现27 kDa的蛋白水解物。凝血酶诱导BTK在30min后降解约10%。钙蛋白酶抑制剂阻止了BTK在这两种情况下的降解。Wiskott-Aldrich综合征蛋白(Wasp)和BTK底物Wiskott-Aldrich综合征蛋白(WASP)的蛋白分解产物和BTK的27 kDa降解产物与未切割的蛋白相反，没有重新分布到凝血酶聚集的血小板中不溶于Triton的细胞骨架。BTK和WASP的降解与其酪氨酸磷酸化状态无关。这些结果表明，BTK是钙蛋白酶的内源性底物，其裂解可能在血小板的长期聚集后事件中具有功能后果。
Platelet-associated Bruton’s tyrosine kinase (Btk) was completely cleaved if treated with calcium ionophore A23187 with appearance of a proteolytic product of 27 kDa size. Aggregation with thrombin also induced about 10% degradation of Btk after 30 min. Calpain inhibitors prevented Btk degradation in both. The proteolytic products of the Wiskott–Aldrich syndrome protein (WASP), a calpain and Btk substrate, and the 27 kDa degradation product of Btk did not redistribute to the Triton-insoluble cytoskeleton in thrombin-aggregated platelets, in contrast to the uncleaved proteins. The degradation of Btk and WASP was independent of their tyrosine phosphorylation status. These results indicate that Btk is an endogenous substrate for calpain, the cleavage of which may have functional consequences in long-term post-aggregation events in platelets.