Affixin activates Rac1 via βPIX in C2C12 myoblast
- 作者：Chie Matsuda ; Kimihiko Kameyama ; Atsushi Suzuki ; Wataru Mishima ; Satoshi Yamaji ; Harumasa Okamoto ; Ichizo Nishino ; Yukiko K. Hayashi
- 关键词：Affixin/β ; -parvin ; Lamellipodia ; β ; PIX ; Cytoskeletal actin
- 刊名：FEBS Letters
- 出版年：2008
- 期刊代码：70_00145793
- 类别：bio
- 出版时间：9 April 2008
- 卷：582
- 期：8
- 页码：1189-1196
- 文件大小：1128 K
摘要
Affixin/β-parvin is an integrin-linked kinase (ILK)-binding focal adhesion protein highly expressed in skeletal muscle and heart. To elucidate the possible role of affixin in skeletal muscle, we established stable C2C12 cell line expressing T7-tagged human affixin (C2C12-affixin cells). Exogenous expression of affixin promotes lamellipodium formation where affixin, ILK 
k small letter alpha" title="greek small letter alpha" border="0">p21-activated kinase (PAK)-interactive exchange factor (PIX) and βPIX accumulate. The association of affixin and βPIX was confirmed by immunoprecipitation and pull down assay. In C2C12-affixin cells, an increased level of activated Rac1 but not Cdc42 was observed, and mutant βPIX lacking guanine nucleotide exchange factor activity inhibited lamellipodium formation. These results suggest that affixin is involved in reorganization of subsarcolemmal cytoskeletal actin by activation of Rac1 through k small letter alpha" title="greek small letter alpha" border="0"> and βPIXs in skeletal muscle.
k small letter alpha" title="greek small letter alpha" border="0">p21-activated kinase (PAK)-interactive exchange factor (PIX) and βPIX accumulate. The association of affixin and βPIX was confirmed by immunoprecipitation and pull down assay. In C2C12-affixin cells, an increased level of activated Rac1 but not Cdc42 was observed, and mutant βPIX lacking guanine nucleotide exchange factor activity inhibited lamellipodium formation. These results suggest that affixin is involved in reorganization of subsarcolemmal cytoskeletal actin by activation of Rac1 through k small letter alpha" title="greek small letter alpha" border="0"> and βPIXs in skeletal muscle.