Evidence for the involvement of p59fyn and p53/56lyn in collagen receptor signalling in human platelets
Evidence for the involvement of p59fyn and p53/56lyn in collagen receptor signalling in human platelets
复制标题
DOI：
10.1042/0264-6021:3380203
复制
发表时间：
1999-02-15
影响因子：
4.1
通讯作者：
Watson, SP
中科院分区：
文献类型：
--
作者：
Briddon, SJ;Watson, SP
胶原蛋白与血小板糖蛋白VI（GPVI）的结合导致磷脂酶C γ 2通过依赖于Fc受体γ（FcR γ）链和酪氨酸激酶p72（svk）的途径活化。我们研究了血小板Src家族激酶在这一信号通路中的作用。选择性Src家族激酶抑制剂PP 1可防止胶原蛋白刺激的全细胞酪氨酸磷酸化和FcR γ链和p72（syk）酪氨酸磷酸化的增加。对胶原相关肽（CRP）进行了类似的观察，CRP与GPVI结合，但不与整合素α（2）β（1）（GPIa/IIa）结合。这些作用在PP 1浓度下观察到，PP 1抑制CRP诱导的血小板聚集、致密颗粒释放和Ca 2+动员，但不抑制G蛋白偶联受体激动剂凝血酶介导的聚集和Ca 2+动员。在CRP或胶原刺激后，Src家族激酶p59（fyn）和p53/56（林恩）与包括FcR γ链在内的几种酪氨酸磷酸化蛋白质相关。在基础条件下也观察到FcR γ链和p59（fyn）之间的关联，并且仅在弱去污剂Brij 96中稳定，而在Nonidet P40中不稳定，表明非SH 2依赖性相互作用。这些结果为p59（fyn）和p53/56（林恩）通过GPVI参与信号传导提供了强有力的证据，其中p59（fyn）可能在FcR γ链磷酸化的上游起作用。
The binding of collagen to platelet glycoprotein VI (GPVI) leads to the subsequent activation of phospholipase C gamma 2 through a pathway that is dependent on the Fc receptor gamma (FcR gamma) chain and the tyrosine kinase p72(svk). We have investigated the role of platelet Src-family kinases in this signalling pathway. The selective Src-family kinase inhibitor PP1 prevented collagen-stimulated increases in whole-cell tyrosine phosphorylation and tyrosine phosphorylation of the FcR gamma chain and p72(syk). A similar set of observations was made for a collagen-related peptide (CRP), which binds to GPVI but not to the integrin alpha(2)beta(1) (GPIa/IIa). These effects were seen at a concentration of PP1 that inhibited platelet aggregation, dense granule release and Ca2+ mobilization induced by CRP, but not aggregation and Ca2+ mobilization mediated by the G-protein-coupled receptor agonist thrombin. After stimulation by CRP or collagen, the Src-family kinases p59(fyn) and p53/56(lyn) became associated with several tyrosine-phosphorylated proteins including the FcR gamma chain. This was not true of the other platelet Src-family kinases, The association between the FcR gamma chain and p59(fyn) was also seen under basal conditions, and was stable only in the weak detergent Brij96 but not in Nonidet P40, suggesting a non-SH2-dependent interaction. These results provide strong evidence for the involvement of p59(fyn) and p53/56(lyn) in signalling via GPVI, with p59(fyn) possibly acting upstream of FcR gamma chain phosphorylation.