ACE as a Mechanosensor to Shear Stress Influences the Control of Its Own Regulation via Phosphorylation of Cytoplasmic Ser1270
ACE as a Mechanosensor to Shear Stress Influences the Control of Its Own Regulation via Phosphorylation of Cytoplasmic Ser1270
复制标题
DOI：
10.1371/journal.pone.0022803
复制
发表时间：
2011-08-25
期刊：
影响因子：
3.7
通讯作者：
Krieger, Jose Eduardo
中科院分区：
文献类型：
--
作者：
Barauna, Valerio Garrone;Gastalho Campos, Luciene Cristina;Krieger, Jose Eduardo
目的：方法和结果：Western blotting分析显示，剪切应力（SS）（18 h，15 dyn/cm（2））可降低人原代内皮细胞（EC）中ACE的表达和磷酸化水平，并抑制p-JNK的表达。表达野生型ACE（wt-ACE）的CHO细胞也显示SS诱导的ACE和p-JNK降低。此外，SS降低了wt-ACE中的ACE启动子活性，但对野生型CHO或表达ACE但无胞外或胞内结构域的CHO没有影响，并且与wt-ACE相比，在表达Ser（1270）突变ACE的CHO中降低较少（分别为13%和40%）。JNK抑制剂（SP 600125，18小时），在SS的情况下，也降低了ACE启动子活性的wt-ACE。最后，SS诱导的抑制ACE的表达和磷酸化EC抵消同时暴露于ACE inhibitors.Conclusions：ACE显示了自己的下调响应SS的关键作用。这种反应需要胞外和胞内结构域以及ACE Ser（1270），这与胞外结构域作为机械传感器而胞质结构域通过Ser（1270）上的磷酸化激发下游胞内信号传导的想法一致。
Objectives: We tested whether angiotensin converting enzyme (ACE) and phosphorylation of Ser(1270) are involved in shear-stress (SS)-induced downregulation of the enzyme.Methods and Results: Western blotting analysis showed that SS (18 h, 15 dyn/cm(2)) decreases ACE expression and phosphorylation as well as p-JNK inhibition in human primary endothelial cells (EC). CHO cells expressing wild-type ACE (wt-ACE) also displayed SS-induced decrease in ACE and p-JNK. Moreover, SS decreased ACE promoter activity in wt-ACE, but had no effect in wild type CHO or CHO expressing ACE without either the extra-or the intracellular domains, and decreased less in CHO expressing a mutated ACE at Ser(1270) compared to wt-ACE (13 vs. 40%, respectively). The JNK inhibitor (SP600125, 18 h), in absence of SS, also decreased ACE promoter activity in wt-ACE. Finally, SS-induced inhibition of ACE expression and phosphorylation in EC was counteracted by simultaneous exposure to an ACE inhibitor.Conclusions: ACE displays a key role on its own downregulation in response to SS. This response requires both the extra- and the intracellular domains and ACE Ser(1270), consistent with the idea that the extracellular domain behaves as a mechanosensor while the cytoplasmic domain elicits the downstream intracellular signaling by phosphorylation on Ser(1270).