Pleckstrin Homology Domain Interacting Protein (PHIP)

PHIP binds the pleckstrin homology (PH) domain of insulin receptor substrate-1 (IRS1), modulates insulin signaling, and plays a role in pancreatic beta cell growth and survival .The deduced 902-amino acid mouse and human proteins have a calculated molecular mass of 100 kD. Both have 2 predicted bromodomains that share 44% identity with the bromodomain of mouse CREB-binding protein (CREBBP). Northern blot analysis of adult mouse tissues detected a 7.0-kb transcript with widespread expression. Western blot analysis of human myeloma cell lysates detected a long 104-kD isoform and a shorter 97-kD isoform, which were predicted to arise from alternative usage of 2 putative translation initiation sites.