Lamellipodium tip actin barbed ends serve as a force sensor.

ABSTRACT: Cells change direction of migration by sensing rigidity of environment and traction force, yet its underlying mechanism is unclear. Here, we show that tip actin barbed ends serve as an active "force sensor" at the leading edge. We established a method to visualize intracellular single-molecule fluorescent actin through an elastic culture substrate. We found that immediately after cell edge stretch, actin assembly increased specifically at the lamellipodium tip. The rate of actin assembly increased with increasing stretch speed. Furthermore, tip actin polymerization remained elevated at the subsequent hold step, which was accompanied by a decrease in the load on the tip barbed ends. Stretch-induced tip actin polymerization was still observed without either the WAVE complex or Ena/VASP prote

SUBMITTER: Koseki K 

PROVIDER: S-EPMC6856401 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature