Figure 1.

Talin Binding of Active Vinculin Is Essential for Its Ability to Bypass the Requirement of Actomyosin Tension for FA Stabilization

(A) Graphical representation of vinculin constructs that were expressed as GFP-fusion constructs in this study. Proteins binding to the individual domains of vinculin are indicated below.

(B) MEFvin^−/− cells coexpressing LifeAct-mRFP together with indicated vinculin constructs were treated with Y-27632. Full-length vinculin, but not vin258, vin880, and vinT12 (Movie S1), leaves FAs under these conditions. Vinculin forms carrying an A50I mutation that reduces their binding to talin (vinFL-A50I and vinT12-A50I) are released from FAs in the absence of intracellular tension. Similar results were obtained by treating the cells with cytochalasin D and blebbistatin (Figure S1 and Movie S1). Scale bar represents 5 μm.

(C) Quantification of the normalized number and area fraction of vinculin-positive FAs over time. The vertical red dashed line indicates the beginning of the Y-27632 treatment (±SEM, n > 10 cells from two independent experiments).