Endothelin-1 promotes migration of endothelial cells through the activation of ARF6 and the regulation of FAK activity
Endothelin-1 promotes migration of endothelial cells through the activation of ARF6 and the regulation of FAK activity
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DOI：
10.1016/j.cellsig.2008.08.021
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发表时间：
2008-12-01
影响因子：
4.8
通讯作者：
Claing, Audrey
中科院分区：
文献类型：
--
作者：
Daher, Zeinab;Noel, Josette;Claing, Audrey
几种蛋白质协同作用，促进肌动蛋白细胞骨架在迁移过程中的重塑。这一过程受到adp -核糖基化因子（ARF）蛋白家族的小gtp结合蛋白的高度调节。在这里，我们发现内皮素-1 （ET-1）可以通过激活ETB受体促进ARF6的激活和内皮细胞的迁移。使用RNA干扰抑制ARF6表达可显著损害基础和ET-1刺激的细胞迁移。而ARF1的缺失则无显著影响。为了描述潜在的机制，我们检查了内皮细胞在ET-1刺激后激活的信号事件。在这里，我们发现这种激素促进局灶黏附激酶（FAK）， Erk1/2的磷酸化，以及FAK与Src的关联，以及FAK与GIT1的关联。这些已被证明是重要的形成和转移局灶粘连。在未受刺激的细胞中，ARF6的消耗导致FAK和Erk1/2磷酸化增加，与ET-1处理的细胞中观察到的情况相似。在这些条件下，FAK被发现与可溶性酪氨酸激酶Src组成相关。相反，ARF6的缺失会削弱GIT1与FAK形成激动剂促进复合物的能力，从而阻止局灶粘连的分解。因此，ARF6缺失的内皮细胞形成毛细血管的能力受损。综上所述，我们的数据表明，ARF6在调节内皮细胞的局灶黏附转换中起核心作用。我们的研究提供了一个分子机制，通过这个小GTPase调节细胞运动，最终血管生成。(c) 2008爱思唯尔公司版权所有。
Several proteins act in concert to promote remodeling of the actin cytoskeleton during migration. This process is highly regulated by small GTP-binding proteins of the ADP-ribosylation factor (ARF) family of proteins. Here, we show that endothelin-1 (ET-1) can promote the activation of ARF6 and migration of endothelial cells through the activation of ETB receptors. Inhibition of ARF6 expression using RNA interference markedly impairs basal and ET-1 stimulated cell migration. In contrast, depletion of ARF1 has no significant effect. In order to delineate the underlying mechanism, we examined the signaling events activated in endothelial cells following ET-1 stimulation. Here, we show that this hormone promotes the phosphorylation of focal adhesion kinase (FAK), Erk1/2, and the association of FAK to Src, as well as of FAK to GIT1. These have been shown to be important for the formation and turnover of focal adhesions. In non-stimulated cells, depletion of ARF6 leads to increased FAK and Erk1/2 phosphorylation, similar to what is observed in ET-1 treated cells. In these conditions, FAK is found constitutively associated with the soluble tyrosine kinase, Src. In contrast, depletion of ARF6 impairs the ability of GIT1 to form an agonist promoted complex with FAK, thereby preventing disassembly of focal adhesions. As a consequence, ARF6 depleted endothelial cells are impaired in their ability to form capillary tubes. Taken together, our data suggest that ARF6 is central in regulating focal adhesion turnover in endothelial cells. Our study provides a molecular mechanism by which, this small GTPase regulates cell motility, and ultimately angiogenesis. (c) 2008 Elsevier Inc. All rights reserved.