GRB2 Associated Binding Protein 2 (GAB2)

GAB2 is a member of the GRB2-associated binding protein (GAB) gene family. These proteins contain pleckstrin homology (PH) domain, and bind SHP2 tyrosine phosphatase and GRB2 adapter protein. They act as adapters for transmitting various signals in response to stimuli through cytokine and growth factor receptors, and T- and B-cell antigen receptors. The protein encoded by this gene is the principal activator of phosphatidylinositol-3 kinase in response to activation of the high affinity IgE receptor. Two alternatively spliced transcripts encoding different isoforms have been described for this gene. In contrast to the reciprocal effects of GAB1 and GAB2 in mediating ELK1 induction, these 2 molecules have a similar function in extracellular signal-regulated kinase activation induced by either oncogenic Ras or growth factor stimulation.