GRB2 Associated Binding Protein 3 (GAB3)

GAB3 is a member of the GRB2-associated binding protein gene family. These proteins are scaffolding/docking proteins that are involved in several growth factor and cytokine signaling pathways, and they contain a pleckstrin homology domain, and bind SHP2 tyrosine phosphatase and GRB2 adapter protein. The protein encoded by this gene facilitates macrophage differentiation. Two transcript variants encoding different isoforms have been found for this gene. The deduced 586-amino acid protein contains an N-terminal pleckstrin homology (PH) domain and potential SH2- and SH3-binding motifs. The PH domains of GAB1, GAB2, and GAB3 share about 50% amino acid identity, while the remainder of the proteins share about 14% identity. Gab3 was expressed in all myeloid and macrophage cell lines examined.