Binding of SCF to KIT induces the activation and rapid increase in kinase activity of multiple Src family kinases (SFK), including Src, Lck, Tec, Fyn, and Lyn (Timokhina et al. 1998, Krystal et al. 1998, Linnekin et al. 1997, Lennartsson et al. 1999, Tang et al. 1994, Samayawardhena et al. 2007). The tyrosine residues Y568 and Y570 in KIT juxtamembrane region are involved in the association of SFKs (Price et al. 1997).
SFKs recruited to KIT induce proliferation and chemotaxis in primary hematopoietic progenitor cells or bone marrow derived mast cells (O'Laughlin-Bunner et al. 2001). SCF activated SFKs also mediate a critical signal for lymphocyte development (Agosti et al. 2004). Timokhina et al. demonstrated that Src kinase and PI3-kinase signaling pathways converge to activate Rac1 and JNK after SCF stimulation in BMMC, promoting cell proliferation (Timokhina et al., 1998, Reber et al. 2006 ).