The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is adenylate cyclase inhibition. Signaling promotes phospholipase C activity, leading to the release of inositol trisphosphate (IP3); this then triggers calcium ion release into the cytosol. Interacts with ARRB1 and ARRB2. Interacts with RACK1; the interaction regulates CHRM2 internalization. Phosphorylation in response to agonist binding promotes receptor internalization. Up-regulated in response to enterovirus 71 (EV71) infection. Phosphorylated in response to agonist treatment. Genetic variations in CHRM2 can influence susceptibility to alcoholism [MIM:103780]. Disease susceptibility is associated with variants affecting the gene represented in this entry. Belongs to the G-protein coupled receptor 1 family. Muscarinic acetylcholine receptor subfamily. CHRM2 sub-subfamily.