JAK2 phosphorylation of GHR Activated JAK2 phosphorylates multiple tyrosine residues on GHR (Argetsinger et al. 1993, VanderKuur et al. 1994) including Y332 (VanderKuur 1995), Y487, Y534, Y566, and Y627 (Wang et al. 1996). Wang et al. using the porcine receptor found that phosphorylation at any of the positions they examined (all conserved in humans) was sufficient for STAT5 phosphorylation. While STAT5 activation requires phosphorylation of the distal region of GHR, this has no effect on STAT1 or STAT3 activation (Yi et al. 1996) suggesting different mechanisms. Mutation of Y332 to F in a truncated form of GHR with only the first 54 residues of the cytoplasmic domain had no effect on JAK2 activation or cell proliferation presumed to be mediated by ERK (Wang et al. 1995) so the significance of phosphorylation at this position is unclear. SHP2 binds to Y595 of rat GHR (identical numbering in humans) and to a lesser extent Y487; mutation of these residues impairs the association (Stofega et al. 2000). SOCS3 binds to rat GHR Y333 (equivalent of human Y332), Y338 (not conserved in humans) (Ram & Waxman 1999) and Y487 (Hansen et al. 1999). SOCS-1 has been implicated as a direct inhibitor of JAK kinases (Yasukawa et al. 1999). This reaction represents the phosphorylation of all GHR tyrosines known to be phosphorylated by JAK2. Authored: Jupe, S, 2010-10-14 EC Number: 2.7.10 Edited: Jupe, S, 2011-06-10 Pubmed10064597 Pubmed10551777 Pubmed10976913 Pubmed3349036 Pubmed7535764 Pubmed7545168 Pubmed7691587 Pubmed8063815 Pubmed8343952 Pubmed8923468 Pubmed9121492 Reactome Database ID Release 43982807 Reactome, http://www.reactome.org ReactomeREACT_111147 Reviewed: Herington, AC, 2011-06-13 Reviewed: Waters, MJ, 2011-06-23 has a Stoichiometric coefficient of 10 Growth Hormone: Activated Growth Hormone Receptor- p(Y1007)-JAK2 dimer Growth Hormone: Tyrosine phosphorylated Growth Hormone Receptor-p(Y1007)-JAK2 dimer