Molecular characterization of the ligand-receptor interaction of neuropeptide Y

Neuropeptide Y (NPY) consists of 36 amino acids and is one of the most abun dant peptides in the peripheral and central nervous system. Several subtype s of NPY receptors have been described (Y-1 - y(6)) using segments and anal ogues of NPY. The Y-1-, Y-2- and the Y-5-receptor, which have been cloned, belong to the G-protein coupled hormone receptor family and will be special ly addressed, because they are the endogenous binding sites of neuropeptide Y in human. In contrast, Y-4-receptors recognize endogenous PP, Y-3-recept ors are discussed controversially and the ys-receptor is truncated in human . In this review, we summarize the data of neuropeptide Y with respect to l igand binding, selectivity, receptor structures and ligand-receptor complex es by using ligand analogues, site directed mutagenesis and photoaffinity l abeling.