Meta-Biol

• Pathways

SCF induces rapid and transient autophosphorylation of JAK2 bound to c-KIT. JAKs bound to activated, dimerized receptors cross-phosphorylate and thereby activate each other. Multiple phosphorylation sites have been identified in JAK2 (tyrosines 221, 570, 868, 966, 972, 1007 and 1008 ). Phosphorylation of tyrosine 1007 is essential for kinase activity (Feng et al 1997, Argetsinger et al. 2004, 2010). Tyrosine 1007 is in the activation loop and phosphorylation allows access of the catalytic loop to the ATP in the ATP binding domain. Of all the predicted phoshorylation sites only the critical tyrosine 1007 is represented in the reaction.