Phosphorylation of ITIM in SIRP alpha Authored: Garapati, P V, 2009-02-12 18:17:40 EC Number: 2.7.10 Edited: Garapati, P V, 2009-02-12 18:17:40 Pubmed16691243 Pubmed17584740 Reactome Database ID Release 43391156 Reactome, http://www.reactome.org ReactomeREACT_23920 Reviewed: Barclay, AN, 2010-05-20 Various growth factors and events such as integrin-mediated cell adhesion to extracellular matrix (ECM) proteins induce the tyrosine phosphorylation of SIRP alpha. The cytoplasmic tail of SIRP alpha has two ITIMs with four tyrosine residues that are potential sites for phosphorylation. Phosphorylation is not dependent on CD47 engagement but the presence of CD47 may enhance the effect. Src family kinases may be involved in the phosphorylation. has a Stoichiometric coefficient of 4 SIRP alpha:CD47 pSIRP alpha:CD47