Growth factor receptor-bound protein 14 (Grb14) is the final described member of the Grb7 family of proteins, containing Grb7, Grb10 and Grb14. The Grb7 family all share a series of domains involved in protein-protein and protein-lipid interactions.
Under ligand induction, Grb14 binds to various receptor tyrosine kinases (RTKs), this interaction relies on the specific SH2 and PIR domains. These domains are likely a determinant of the specificity of Grb14 action.
Grb14-RTK interactions are established to be necessary for insulin (IR) receptors; by acting as an inhibitor of IR tyrosine kinase activity, Grb14-RTK complexes are capable of inhibiting insulin effects. Grb14 is a molecular adapter which can specifically bind to activated insulin receptors and inhibit its tyrosine kinase activity. Molecules capable of disrupting this binding have been shown to have potential as insulin sensitising agents.