This is one of the several different receptors for 5-hydroxytryptamine (serotonin), a biogenic hormone that functions as a neurotransmitter, a hormone, and a mitogen. The activity of this receptor is mediated by G proteins that stimulate adenylate cyclase.
Subcellular locations: Cell membrane, Endosome
Interaction with SNX27 mediates recruitment to early endosomes, while interaction with NHERF1 and EZR might target the protein to specialized subcellular regions, such as microvilli.
Isoform 5-HT4(A) is expressed in ileum, brain, and atrium, but not in the ventricle.