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: GPCR, family 1; Membrane protein, integral; Membrane protein, multi-pass; Receptor, GPCR
Biological Process: behavioral response to ethanol; cellular response to stress; G-protein signaling, coupled to cyclic nucleotide second messenger; G-protein signaling, coupled to IP3 second messenger (phospholipase C activating); negative regulation of adenylate cyclase activity; negative regulation of cell proliferation; positive regulation of neurogenesis; sensory perception of pain; synaptic transmission