Spatial relationships between vinculin tension and actin at cell adhesions define cell colony positioning and identity.

The protein vinculin mediates actin-myosin-dependent adhesion strength to regulate force transmission at cellular adhesions. The precise distribution of forces sensed by vinculin that regulates downstream cellular processes remains unclear. To determine vinculin tension in multiple cell types, a FRET-based tension-sensitive module was knocked into the vinculin locus of human induced pluripotent stem cells. Measurements of vinculin tension and adhesion spatial distributions were used to create mechanical profiles that identify cellular origin and differentially correlate to cell shape characteristics. In stem cell colonies, edge cell morphology depended on high vinculin tension in basal adhesions connected to actin. These mechanical signatures were able to determine progression toward cardiomyocyte versus neural lineage commitment. Our findings suggest that spatial mapping of vinculin tension can define mechanical profiles that differentially correlate to cell morphologies that affect cell function and lineage fate.