Polycystin-2 is a member of the polycystin protein family, called TRPP1, previously known as polycystin-2, PC2 or APKD2. TRPP1 contains multiple transmembrane domains, and cytoplasmic N- and C-termini. The protein may be an integral membrane protein involved in cell-cell/matrix interactions.  TRPP1 may function in renal tubular development, morphology, and function, and may modulate intracellular calcium homoeostasis and other signal transduction pathways. This protein interacts with polycystin 1 to produce cation-permeable currents.Strongly expressed in ovary, fetal and adult kidney, testis, and small intestine. Not detected in peripheral leukocytes.