Regulation of PKC autophosphorylation by calponin in contractile vascular smooth muscle tissue.
Regulation of PKC autophosphorylation by calponin in contractile vascular smooth muscle tissue.
复制标题
收缩性血管平滑肌组织中钙调蛋白对 PKC 自磷酸化的调节。
DOI：
10.1155/2013/358643
复制
发表时间：
2013
影响因子：
--
通讯作者：
Morgan,KathleenG
中科院分区：
文献类型：
--
作者：
Kim,HakRim;Gallant,Cynthia;Morgan,KathleenG
Protein kinase C (PKC) is a key enzyme involved in agonist‐induced smooth muscle contraction. In some cases, regulatory phosphorylation of PKC is required for full activation of the enzyme. However, this issue has largely been ignored with respect to PKC‐dependent regulation of contractile vascular smooth muscle (VSM) contractility. The first event in PKC regulation is a transphosphorylation by PDK at a conserved threonine in the activation loop of PKC, followed by the subsequent autophosphorylation at the turn motif and hydrophobic motif sites. In the present study, we determined whether phosphorylation of PKC is a regulated process in VSM and also investigated a potential role of calponin in the regulation of PKC. We found that calponin increases the level of in vitro PKCαphosphorylation at the PDK and hydrophobic sites, but not the turn motif site. In vascular tissues, phosphorylation of the PKC hydrophobic site, but not turn motif site, as well as phosphorylation of PDK at S241 increased in response to phenylephrine. Calponin knockdown inhibits autophosphorylation of cellular PKC in response to phenylephrine, confirming results with recombinant PKC. Thus these results show that autophosphorylation of PKC is regulated in dVSM and calponin is necessary for autophosphorylation of PKC in VSM.
