Anti-MOR1 antibodies are protein reagents that detect specific antigens. The MOR1 antigen is another term for the human protein opioid receptor mu 1, encoded by the OPRM1 gene. The protein is a known receptor for endogenous opioids such as beta-endorphin and endomorphin. Canonically, it has an amino acid length of 400 residues and a mass of 44.8 kilodaltons. Its subcellular localization is in the cell membrane and it is reported to be expressed in the brain. The MOR1 protein is a member of the G-protein coupled receptor 1 protein family.