Fig. 3
From: Platelet integrin αIIbβ3: signal transduction, regulation, and its therapeutic targeting
Schematic of integrin αIIbβ3 outside-in signaling in platelets. Following ligand binding to the extracellular domain of integrin αIIbβ3, integrin αIIbβ3 clustering promotes Src activation by autophosphorylation. Calpain cleaves the integrin β3 cytoplasmic tail and leads to disassociation of partly active Src from the integrin β3 tail. Src phosphorylates and supports the activation of a wide range of enzymes and signaling proteins, such as FAK, Syk kinase, RhoGAP, Rac-GEFs, RhoGEFs, and PI3K. Gα13, talin, kindlin, tensin, and vinculin provide the necessary links between the integrin β3 cytoplasmic tail and actin. Kindlin can directly couple integrin β3 to the actin cytoskeleton via the ILK/PINCH/parvin complex