Critical roles of phosphorylation and actin binding motifs, but not the central proline-rich region, for Ena/vasodilator-stimulated phosphoprotein (VASP) function during cell migration
Critical roles of phosphorylation and actin binding motifs, but not the central proline-rich region, for Ena/vasodilator-stimulated phosphoprotein (VASP) function during cell migration
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DOI：
10.1091/mbc.e01-10-0102
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发表时间：
2002-07-01
影响因子：
3.3
通讯作者：
Gertler, FB
中科院分区：
文献类型：
--
作者：
Loureiro, JJ;Rubinson, DA;Gertler, FB
Ena/血管扩张剂刺激的磷酸蛋白(VASP)家族参与了许多基于肌动蛋白的细胞过程的调节，包括整个细胞转位所必需的片层脂膜突起。越来越多的证据主要来自于使用纯化蛋白、无细胞提取物和病原体运动性的体外生化实验，已经开始表明Ena/Vasp蛋白在肌动蛋白动力学控制中的各种机制作用。利用EnA/Vasp缺陷细胞的表型互补和正常成纤维细胞的过度表达，我们通过突变该蛋白家族中发现的高度保守的序列元件，分析了该家族成员MENA中的一组突变的功能。令人惊讶的是，肌动蛋白单体结合蛋白profilin结合所需的位点的缺失对Mena调节随机细胞运动的能力没有影响。profilin是Ena/Vasp蛋白的已知配体。我们的分析揭示了Ena/Vasp在细胞运动中发挥作用所必需的两个特征，即环核苷酸依赖的激酶磷酸化位点和F-肌动蛋白结合基序。有趣的是，仅表达C-末端EVH2结构域就足以弥补随机细胞运动中Ena/Vasp功能的丧失。
The Ena/vasodilator-stimulated phosphoprotein (VASP) protein family is implicated in the regulation of a number of actin-based cellular processes, including lamellipodial protrusion necessary for whole cell translocation. A growing body of evidence derived largely from in vitro biochemical experiments using purified proteins, cell-free extracts, and pathogen motility has begun to suggest various mechanistic roles for Ena/VASP proteins in the control of actin dynamics. Using complementation of phenotypes in Ena/VASP-deficient cells and overexpression in normal fibroblasts, we have assayed the function of a panel of mutants in one member of this family, Mena, by mutating highly conserved sequence elements found in this protein family. Surprisingly, deletion of sites required for binding of the actin monomer-binding protein profilin, a known ligand of Ena/VASP proteins, has no effect on the ability of Mena to regulate random cell motility. Our analysis revealed two features essential for Ena/VASP function in cell movement, cyclic nucleotide-dependent kinase phosphorylation sites and an F-actin binding motif. Interestingly, expression of the C-terminal EVH2 domain alone is sufficient to complement loss of Ena/VASP function in random cell motility.