PHIP also known as ndrp, WDR11 is a crucial 1,821 amino acid protein characterized by eight N-terminal WD40 repeats and two bromodomains. PHIP is predominantly expressed in skeletal muscle, where PHIP localizes to both cytosol and nucleus, as well as in primary β cells, where PHIP is found in the nucleus. PHIP functions as a transcriptional activator and plays a significant role in insulin signaling by interacting with members of the insulin receptor substrate (IRS) family, particularly IRS-1 and IRS-2. These interactions are vital for mediating insulin receptor signaling, which is essential for proliferation and survival of insulin-producing β cells. PHIP′s association with the PH domain of IRS-1 suggests PHIP may serve as a critical link between IRS-1 and insulin receptors, thereby influencing regulation of insulin signaling pathways.