Relationship between Traction Forces and Focal Adhesions

Beningo et al., J. Cell Biol. 153:881-887 (2001)

Traction forces are inward mechanical forces exerted at focal adhesions, through the linkage of integrins with the extracellular matrix. It was unclear how these forces might be coordinated among focal adhesions in different regions of a migrating cell. Fish fibroblasts expressing GFP-zyxin, a component of the focal adhesion, were imaged on a polyacrylamide flexible substrate for simultaneous imaging of traction forces and focal adhesions.

Complex Relationship between GFP-Zyxin and Traction Forces during Cell Migration

The distribution of traction stress is shown to the right as pseudocolor images, with "hot" colors representing strong forces. Although many focal adhesions appear to exert strong forces, the relationship is by no means simple. Careful analysis indicates that strong forces are located in regions where new focal adhesions appear. The tail region also show strong traction forces, which refect passive resistance from our other studies. Recording time, 120 min.