School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, 325035, Zhejiang, China.
Cell Commun Signal. 2023 Jul 24;21(1):182. doi: 10.1186/s12964-023-01189-y.
Cell migration is a highly orchestrated process requiring the coordination between the cytoskeleton, cell membrane and extracellular matrix adhesions. Our previous study demonstrated that Hax1 interacts with EB2, a microtubule end-binding protein, and this interaction regulate cell migration in keratinocytes. However, little is known about the underlying regulatory mechanism. Here, we show that Hax1 links dynamic focal adhesions to regulate cell migration via interacting with IQGAP1, a multidomain scaffolding protein, which was identified by affinity purification coupled with LC-MS/MS. Biochemical characterizations revealed that C-terminal region of Hax1 and RGCT domain of IQGAP1 are the most critical binding determinants for its interaction. IQGAP1/Hax1 interaction is essential for cell migration in MCF7 cells. Knockdown of HAX1 not only stabilizes focal adhesions, but also impairs the accumulation of IQGAP in focal adhesions. Further study indicates that this interaction is critical for maintaining efficient focal adhesion turnover. Perturbation of the IQGAP1/Hax1 interaction in vivo using a membrane-permeable TAT-RGCT peptide results in impaired focal adhesion turnover, thus leading to inhibition of directional cell migration. Together, our findings unravel a novel interaction between IQGAP1 and Hax1, suggesting that IQGAP1 association with Hax1 plays a significant role in focal adhesion turnover and directional cell migration. Video Abstract.
细胞迁移是一个高度协调的过程，需要细胞骨架、细胞膜和细胞外基质黏附之间的协调。我们之前的研究表明，Hax1 与微管末端结合蛋白 EB2 相互作用，这种相互作用调节角质细胞的细胞迁移。然而，其潜在的调控机制知之甚少。在这里，我们通过亲和纯化结合 LC-MS/MS 发现 Hax1 通过与 IQGAP1 相互作用将动态的焦点黏附连接起来，调节细胞迁移。IQGAP1 是一种多功能支架蛋白。生化特性表明 Hax1 的 C 端区域和 IQGAP1 的 RGCT 结构域是其相互作用的最关键结合决定因素。IQGAP1/Hax1 相互作用对于 MCF7 细胞的迁移是必需的。HAX1 的敲低不仅稳定了焦点黏附，而且损害了 IQGAP 在焦点黏附中的积累。进一步的研究表明，这种相互作用对于维持有效的焦点黏附转化至关重要。使用膜通透性 TAT-RGCT 肽在体内干扰 IQGAP1/Hax1 相互作用会导致焦点黏附转化受损，从而抑制定向细胞迁移。总之，我们的发现揭示了 IQGAP1 和 Hax1 之间的一种新的相互作用，表明 IQGAP1 与 Hax1 的结合在焦点黏附转化和定向细胞迁移中起着重要作用。视频摘要。
