Binding of PIK3 regulatory alpha subunit to GRB2:GAB1 Authored: Castagnoli, L, 2006-10-10 13:09:34 Edited: Orlic-Milacic, Marija, 2011-08-25 Pubmed11606067 Reactome Database ID Release 43177931 Reactome, http://www.reactome.org ReactomeREACT_12616 Reviewed: Heldin, CH, 2008-02-12 09:44:02 The Src homology 2 (SH2) domain of the phosphatidylinositol 3-kinase (PIK3) regulatory subunit (PIK3R1, i.e. PI3Kp85) binds to GAB1 in a phosphorylation-independent manner. GAB1 serves as a docking protein which recruits a number of downstream signalling proteins. PIK3R1 can bind to either GAB1 or phosphorylated GAB1. GRB2:GAB1 GRB2:GAB1:PIK3R1