Figure 2.

Integrin signaling Inside-out signal: Integrins are in an inactive conformation at baseline. However, the activation of receptors such as GPCRs, chemokine receptors, and TCR induces a cascade of events within the cells. The example shown here is via TCR. At the end, talin along with kindlin bind to β subunit of integrins, inducing its conformational change, which triggers the structural change of α subunit, allowing the integrin to bind to its ligand. Outside-in signal: Integrins that bind to their ligands cause cytoskeletal changes via focal adhesion molecules including focal adhesion kinase (FAK), leading to cell proliferation, survival, differentiation, and migration.