The interaction of fibrillar collagen with GPVI leads to the dimerization of the receptor and the association of the ITAM domains of the FcRγ chains. These are phosphorylated by Src family kinases Lyn and Fyn. In the model suggested by the Kunapuli group data, Fyn phosphorylates the Rho GEF TRIO, which in turn activates RhoG [115]. In the model supported by data from our laboratory [112], the activity of the Src family kinases leads to the activation of Syk [112]. The activity of Syk then assembles various signalling adapters, kinases and GEF proteins including Vav, which leads to the GTP loading of RhoG. Active RhoG then interacts with SNARE regulators and SNARE proteins including VAMP2 to promote dense granule secretion. Autocrine and paracrine feedback signalling then occurs through P2Y₁₂ receptors.