The mu-opioid receptor (MOR, encoded by the OPRM1 gene) is a G protein-coupled receptor (GPCR) primarily known for its role in pain modulation, reward processing, and opioid drug responses[1]. Recently, research has uncovered important functions in neurodegeneration and neuroinflammation, making it a therapeutic target of interest for Alzheimer's disease and Parkinson's disease[2].
The OPRM1 gene encodes the mu-opioid receptor protein, a member of the opioid receptor family within the GPCR superfamily.
The mu-opioid receptor consists of:
Upon agonist binding, MOR activates heterotrimeric G proteins (Gi/Go family):
Following phosphorylation, beta-arrestin recruitment leads to:
MOR signaling significantly affects Alzheimer's disease pathogenesis:
MOR plays complex roles in Parkinson's disease:
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