G protein-coupled receptor 39 (GPR39) functions in a phosphatidylinositol-calcium second messenger system in association with G proteins. GPR39 is functionally involved in the regulation of body weight, gastrointestinal mobility, hormone secretion and cell death. In immunohistochemistry, GPR39 has membranous positivity in the basal ganglia, hypothalamus, and pituitary in the nervous system, and it is also found on macrophages and dendritic cells in various tissues. In cancer, it is found on populations of tumor cells in glioblastoma and breast, lung and pancreatic adenocarcinomas. References: The UniProt Consortium. Nucleic Acids Res. 47: D506-515 (2019); Nucleic Acids Res. 2016 Jan 4;44(D1):D733-45, PMID:26553804