Protein kinase A‐dependent increase in WAVE2 expression induced by the focal adhesion protein vinexin
Protein kinase A‐dependent increase in WAVE2 expression induced by the focal adhesion protein vinexin
复制标题
DOI：
10.1111/j.1365-2443.2006.00932.x
复制
发表时间：
2006-03
期刊：
影响因子：
2.1
通讯作者：
Masaru Mitsushima;Takuhito Sezaki;Rie Akahane;K. Ueda;S. Suetsugu;T. Takenawa;N. Kioka
中科院分区：
文献类型：
--
作者：
Masaru Mitsushima;Takuhito Sezaki;Rie Akahane;K. Ueda;S. Suetsugu;T. Takenawa;N. Kioka
粘着斑蛋白vinexin是接头蛋白家族中的一员，被认为参与了细胞黏附、细胞骨架重组和生长因子信号的调节。在这里，我们发现，vinexinβ增加了Wiskott-Aldrich综合征蛋白家族Verprolin同源蛋白(WAVE)2蛋白的数量，并降低了其迁移率，这是调节迁移细胞中肌动蛋白聚合的关键因素。这种运动障碍在体外磷酸酶处理后消失。免疫共沉淀实验表明，vinexinβ与WAVE_2、WAVE_1和N-WASP之间存在相互作用。Vinexinβ通过vinexinβ的第一个和第二个SH3结构域与WAVE2的Pro富集区相互作用。破坏这种相互作用的突变削弱了vinexinβ增加WAVE2蛋白数量的能力。蛋白酶体抑制剂的处理增加了WAVE2的数量，但与vinexinβ没有相加作用。蛋白激酶A活性的抑制抑制了长春新诱导的WAVE2蛋白表达的增加，而激活蛋白激酶A则增加了WAVE2的表达，而没有长春新的β。这些结果表明，vinexinβ以一种PKA依赖的方式调节蛋白酶体依赖的WAVE2的降解。
The focal adhesion protein vinexin is a member of a family of adaptor proteins that are thought to participate in the regulation of cell adhesion, cytoskeletal reorganization, and growth factor signaling. Here, we show that vinexin β increases the amount of and reduces the mobility on SDS‐PAGE of Wiskott‐Aldrich syndrome protein family verprolin‐homologous protein (WAVE) 2 protein, which is a key factor modulating actin polymerization in migrating cells. This mobility retardation disappeared after in vitro phosphatase treatment. Co‐immunoprecipitation assays revealed the interaction of vinexin β with WAVE2 as well as WAVE1 and N‐WASP. Vinexin β interacts with the proline‐rich region of WAVE2 through the first and second SH3 domains of vinexin β. Mutations disrupting the interaction impaired the ability of vinexin β to increase the amount of WAVE2 protein. Treatments with proteasome inhibitors increased the amount of WAVE2, but did not have an additive effect with vinexin β. Inhibition of protein kinase A (PKA) activity suppressed the vinexin‐induced increase in WAVE2 protein, while activation of PKA increased WAVE2 expression without vinexin β. These results suggest that vinexin β regulates the proteasome‐dependent degradation of WAVE2 in a PKA‐dependent manner.