a Gi-protein-coupled receptor for beta-endorphin, morphine and other opiates. Inhibits neurotransmitter release by reducing calcium ion currents and increasing potassium ion conductance. Ligand-binding inactivates adenylyl cyclase, and activates a variety of G-beta-gamma-dependent pathways including the MAPK and the PI3K/Akt cascades. Two splice-variant isoforms have been described. Note: This description may include information from UniProtKB.
Protein type: Membrane protein, integral; GPCR, family 1; Receptor, GPCR; Membrane protein, multi-pass
Cellular Component: Golgi apparatus; endoplasmic reticulum; integral to plasma membrane; plasma membrane
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.