Article

Two distinct actin networks drive the protrusion of migrating cells.

Department of Cell Biology, Scripps Research Institute (TSRI), La Jolla, CA 92037, USA.
Science (impact factor: 31.2). 10/2004; 305(5691):1782-6. DOI:10.1126/science.1100533 pp.1782-6
Source: PubMed

ABSTRACT Cell migration initiates by extension of the actin cytoskeleton at the leading edge. Computational analysis of fluorescent speckle microscopy movies of migrating epithelial cells revealed this process is mediated by two spatially colocalized but kinematically, kinetically, molecularly, and functionally distinct actin networks. A lamellipodium network assembled at the leading edge but completely disassembled within 1 to 3 micrometers. It was weakly coupled to the rest of the cytoskeleton and promoted the random protrusion and retraction of the leading edge. Productive cell advance was a function of the second colocalized network, the lamella, where actomyosin contraction was integrated with substrate adhesion.

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Keywords

actin cytoskeleton
 
Cell migration initiates
 
Computational analysis
 
cytoskeleton
 
fluorescent speckle microscopy movies
 
kinematically
 
lamella
 
leading edge
 
migrating epithelial cells
 
Productive cell advance
 
random protrusion
 
substrate adhesion