Kyoko Nagata-Ohashi, Yusaku Ohta, Kazumichi Goto, Shuhei Chiba, Reiko Mori, Michiru Nishita, Kazumasa Ohashi, Kazuyoshi Kousaka, Akihiro Iwamatsu, Ryusuke Niwa, Tadashi Uemura, Kensaku Mizuno
Cofilin mediates lamellipodium extension and polarized cell migration by stimulating actin filament dynamics at the leading edge of migrating cells. Cofilin is inactivated by phosphorylation at Ser-3 and reactivated by cofilin-phosphatase Slingshot-1L (SSH1L). Little is known of signaling mechanisms of cofilin activation and how this activation is spatially regulated. Here, we show that cofilin-phosphatase activity of SSH1L increases approximately 10-fold by association with actin filaments, which indicates that actin assembly at the leading edge per se triggers local activation of SSH1L and thereby stimulates cofilin-mediated actin turnover in lamellipodia...
May 24, 2004: Journal of Cell Biology