5-hydroxytryptamine 3 receptor, transmembrane domain

Definition

This entry represents the transmembrane (TM) domain of the serotonin 5-HT3 receptors [[cite:PMID:27773795], [cite:PMID:19012743], [cite:PMID:17392525]]. The transmembrane region consists of four transmembrane-spanning α-helical segments (M1-M4) that are linked by loops. The intracellular loop that links M1 and M2 determines the ion selectivity of the channel. The 5-HT3 channel is cation-selective and mediates neuronal depolarization and excitation within the central and peripheral nervous systems. Like other ligand gated ion channels, the 5-HT3 receptor consists of five subunits arranged around a central ion conducting pore, which is permeable to Na+, K+, and Ca2+ ions. Binding of the neurotransmitter 5-hydroxytryptamine (serotonin) to the 5-HT3 receptor opens the channel, which then leads to an excitatory response in neurons, and the rapidly activating, desensitizing, inward current is predominantly carried by Na+ and K+ ions PMID:25119048. This receptor is most closely related by homology to the nicotinic acetylcholine receptor (nAChR) [[cite:PMID:11357122], [cite:PMID:29298898]]. Five subunits have been identified for this family: 5-HT3A, 5-HT3B, 5-HT3C, 5-HT3D, and 5-HT3E, encoded by HTR3A-E genes. Only 5-HT3A subunits are able to form functional homomeric receptors, whereas the 5-HT3B, C, D, and E subunits form heteromeric receptors with 5-HT3A. Different receptor subtypes are important mediators of nausea and vomiting during chemotherapy, pregnancy, and following surgery, while some contribute to neuro-gastroenterologic disorders such irritable bowel syndrome (IBS) and eating disorders as well as comorbid psychiatric conditions [[cite:PMID:26701104], [cite:PMID:21740409], [cite:PMID:14597179], [cite:PMID:21192076], [cite:PMID:17010535], [cite:PMID:23489111]]. 5-HT3 receptor antagonists are established treatments for emesis and IBS, and are beneficial in the treatment of psychiatric diseases PMID:29245992.

5 human proteins with this domain

Each is a reviewed human protein in the Seroatlas serome and a potential autoantibody target; this domain groups them into one antibody-relevant category. Every entry links to its own record.

Download CSV (5 proteins: gene, accession, name)

• HTR3A
• HTR3B
• HTR3C
• HTR3D
• HTR3E