Cell signalling via integrins in anchoring junctions

(a) Outside-in signalling occurs when an integrin binds to a component in the ECM, which transmits a signal to the cytosol, thereby affecting activities inside the cell. In this example the effect is to alter the conformation of part of the cytoskeleton. (b) Inside-out signalling occurs when the cytosol affects the structure of an integrin and thereby changes its ability to bind to components in the ECM. In the example shown here, the effect is to lower the affinity for an ECM component, causing it to release from the integrin component.