Cholecystokinin rapidly stimulates CrkII function in vivo in rat pancreatic acini -: Formation of CrkII-protein complexes
Cholecystokinin rapidly stimulates CrkII function in vivo in rat pancreatic acini -: Formation of CrkII-protein complexes
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DOI：
10.1046/j.1432-1033.2003.03869.x
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发表时间：
2003-12-01
期刊：
影响因子：
--
通讯作者：
Garcia-Marin, LJ
中科院分区：
文献类型：
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作者：
Andreolotti, AG;Bragado, MJ;Garcia-Marin, LJ
Crk 属于衔接蛋白家族，其结构允许与酪氨酸磷酸化蛋白相互作用，因此是下游信号的重要调节剂，代表着众多刺激作用的汇聚。最近，研究表明胆囊收缩素（CCK）可诱导大鼠胰腺腺泡中与纤维应力形成相关的蛋白质酪氨酸磷酸化。在这里，我们研究了 CCK 受体激活是否通过 CrkII 发出信号并与大鼠胰腺腺泡中的酪氨酸磷酸化蛋白形成复合物。我们证明 CCK 促进 CrkII-paxillin 和 CrkII-p130(Cas) 复合物的瞬时形成，并在 1 分钟时达到最大效果。此外，CCK 降低了 CrkII 的电泳迁移率。这种减少是时间和浓度依赖性的，并且与其功能成反比。卡巴胆碱和铃蟾肽也降低了 CrkII 电泳迁移率，而表皮生长因子、血管活性肠肽、促胰液素或垂体腺苷酸环化酶激活多肽则没有影响。 CCK 诱导的 CrkII 电泳位移依赖于酪氨酸激酶的 Src 家族，并且发生在完整动物中，表明 CrkII 在体内外分泌胰腺中介导 CCK 作用的生理作用。
Crk belongs to a family of adapter proteins whose structure allows interaction with tyrosine-phosphorylated proteins and is therefore an important modulator of downstream signals, representing a convergence of the actions of numerous stimuli. Recently, it was demonstrated that cholecystokinin (CCK) induced tyrosine phosphorylation of proteins related to fiber stress formation in rat pancreatic acini. Here, we investigated whether CCK receptor activation signals through CrkII and forms complexes with tyrosine-phosphorylated proteins in rat pancreatic acini. We demonstrated that CCK promoted the transient formation of CrkII-paxillin and CrkII-p130(Cas) complexes with maximal effect at 1 min. Additionally, CCK decreased the electrophoretic mobility of CrkII. This decrease was time- and concentration-dependent and inversely related with its function. Carbachol and bombesin also decreased CrkII electrophoretic mobility, whereas epidermal growth factor, vasoactive intestinal peptide, secretin or pituitary adenylate cyclase-activating polypeptide had no effect. CCK-induced CrkII electrophoretic shift was dependent on the Src family of tyrosine kinases and occurred in the intact animal, suggesting a physiological role of CrkII mediating CCK actions in the exocrine pancreas in vivo.