(145c) F-Actin and Myosin IIa-Dependent Microtubule Targeting of Focal Adhesions

Spatial-temporal targeting of Focal Adhesions (FA) by Microtubule (MT) is thought to be responsible for mediating cell-substrate de-adhesion and promote cell translocation. However, the mechanism behind the targeting phenomenon remains largely unstudied. Here we use Anisotropic Solid Microetching (ASoMiC) to study MT targeting of FA. Combining micropatterning of living cells with high-resolution in-cell imaging permitted the study of the targeting process in quantitative and molecular detail.

Triangular microislands spatially segregate cytoskeletal components and allow for study of MT growth trajectories in defined geometric confines. We show that growing MTs are targeted towards FA. RNAi studies reveal that myosin IIA dependent f-actin bundles are integral to this process.

This study shows that not only are MT guided towards FA, but it also provides methods of quantifying the guidance and investigates the molecular mechanisms behind this process.