西亚试剂优势供应上万种化学试剂产品，欢迎各位新老客户咨询、选购！
中国
联系我们
联系方式：400-990-3999 / 邮箱：sales@xiyashiji.com
西亚试剂 —— 品质可靠，值得信赖
Cofilin Activity Downstream of Pak1 Regulates Cell Protrusion Efficiency by Organizing Lamellipodium and Lamella Actin Networks
Violaine Delorme,1,4 Matthias Machacek,2,4 Céline DerMardirossian,1 Karen L. Anderson,3 Torsten Wittmann,2,5 Dorit Hanein,3 Clare Waterman-Storer,2,6 Gaudenz Danuser,2,
and Gary M. Bokoch1,2,
1 Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA
2 Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
3 Infectious Diseases Program, The Burnham Institute for Medical Research, La Jolla, CA 92037, USA
Corresponding author
Gaudenz Danuser
gdanuser@scripps.edu
Corresponding author
Gary M. Bokoch
bokoch@scripps.edu
Protrusion of the leading edge of migrating epithelial cells requires precise regulation of two actin filament (F-actin) networks, the lamellipodium and the lamella. Cofilin is a downstream target of Rho GTPase signaling that promotes F-actin cycling through its F-actin-nucleating, -severing, and -depolymerizing activity. However, its function in modulating lamellipodium and lamella dynamics, and the implications of these dynamics for protrusion efficiency, has been unclear. Using quantitative fluorescent speckle microscopy, immunofluorescence, and electron microscopy, we establish that the Rac1/Pak1/LIMK1 signaling pathway controls cofilin activity within the lamellipodium. Enhancement of cofilin activity accelerates F-actin turnover and retrograde flow, resulting in widening of the lamellipodium. This is accompanied by increased spatial overlap of the lamellipodium and lamella networks and reduced cell-edge protrusion efficiency. We propose that cofilin functions as a regulator of cell protrusion by modulating the spatial interaction of the lamellipodium and lamella in response to upstream signals.
