FAK phosphorylation at Ser-843 inhibits Tyr-397 phosphorylation, cell spreading and migration
FAK phosphorylation at Ser-843 inhibits Tyr-397 phosphorylation, cell spreading and migration
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DOI：
10.1002/jcp.20870
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发表时间：
2007-02-01
影响因子：
5.6
通讯作者：
Rozengurt, Enrique
中科院分区：
文献类型：
--
作者：
Jacamo, Rodrigo;Jiang, Xiaohua;Rozengurt, Enrique
多重刺激促进酪氨酸磷酸化和粘着斑激酶（FAK）激活，最终促进迁移。关于粘附依赖性信号和细胞骨架组织对丝氨酸位点 FAK 磷酸化调节的影响，或 FAK 丝氨酸磷酸化在细胞迁移中的作用知之甚少。在这里，我们发现，当贴壁细胞从培养基中取出并保持悬浮状态或用细胞松弛素 D 处理贴壁细胞（破坏 F-肌动蛋白细胞骨架并促进粘着斑解体的条件）时，FAK Ser-843 磷酸化显着增加。值得注意的是，Ser-843 磷酸化的增加伴随着 Tyr-397 磷酸化的急剧减少。为了进一步检查这两个磷酸化位点之间的因果关系，我们生成了 Ser-843 磷酸化缺陷和磷酸化模拟的 FAK 突变体。我们发现 Ser-843 突变为天冬氨酸 (FAK[S843D]) 显着降低了整合素刺激细胞中 FAK Tyr-397 的磷酸化。虽然 FAK 缺陷型成纤维细胞的迁移缺陷可以通过 WT FAK 或 FAK[S843A] 的稳定再表达来挽救，但 FAK[S843D] 的稳定再表达未能恢复细胞迁移到伤口裸露区域的能力。我们的结果表明，Ser-843 处的 FAK 磷酸化增加会抑制 Tyr-397 处的 FAK 磷酸化，从而表明这些磷酸化位点之间的串扰机制可以调节 FAK 介导的细胞形状和迁移。 J.细胞。生理学。 210: 436-444, 2007。(c) 2006 wiley-Liss, Inc.
Multiple stimuli promote the tyrosine phosphorylation and activation of focal adhesion kinase (FAK), which ultimately facilitates migration. Little is known about the effect of adhesion-dependent signals and cytoskeleton organization on the regulation of FAK phosphorylation at serine sites, or about the role of FAK serine phosphorylation in cell migration. Here we show that FAK phosphorylation at Ser-843 is strikingly increased when adherent cells are removed from the substratum and held in suspension or by treatment of adherent cells with cytochalasin D, conditions that disrupt the F-actin cytoskeleton and promote focal adhesion disassembly. Notably, the increase in Ser-843 phosphorylation was accompanied by a concomitant sharp decrease in Tyr-397 phosphorylation. To further examine the cause-effect relationship between these two phosphorylation sites we generated Ser-843 phosphorylation-deficient and phosphorylation-mimicking FAK mutants. We found that mutation of Ser-843 to aspartic acid (FAK[S843D]) markedly decreased FAK Tyr-397 phosphorylation in integrin-stimulated cells. While the migratory defect of FAK-deficient fibroblasts was rescued by stable re-expression of WT FAK or FAK[S843A], stable re-expression of FAK[S843D] failed to restore the ability of the cells to migrate into the denuded area of a wound. Our results indicate that increased FAK phosphorylation at Ser-843 represses FAK phosphorylation at Tyr-397, thus suggesting a mechanism of cross-talk between these phosphorylation sites that could regulate FAK-mediated cell shape and migration. J. Cell. Physiol. 210: 436-444, 2007. (c) 2006 wiley-Liss, Inc.