Talin manipulation in cell adhesion through an improved clutch model

Cell adhesion is a key mechanism in biological processes such as cell migration. The clutch model couples the contractile actomyosin cortex inside the cell with the extra-cellular matrix, through a number of adaptor proteins. It has been used to explain how cells can sense force and respond to substrate rigidity. Previous clutch models have provided fundamental understanding in cell adhesion. However, the adhesion composition has been oversimplified, limiting our understanding of how these multiple components of the adhesion influence cell adhesion mechanics. Here, we extend the classical clutch model with a detailed description of talin. Talin consists of a rigid head, a flexible neck and a rod made of 13 domains, which unfold and refold under force. Given the importance of the recruitment of adaptor proteins in a focal adhesion, we implement the presence of 11 vinculin binding sites (VBS) and 3 actin binding sites (ABS) in the talin rod. Our computational framework can easily manipulate VBS and ABS and analyze the effect of its depletion in the cell adhesion mechanics. We compare results of full talin rods and different combinations of talin domains depletion. We show dramatic changes in the traction forces and retrograde flow in our in-silico manipulations of the talin rod.