Ion channels gated by acetylcholine and serotonin： ~tructures, biology, and drug discovery

• Published in: 中国药理学报：英文版 2015 (8), p.895-907
• Main Author: Zhong-shan WU Hao CHENG Yi JIANG Karsten MELCHER H Eric XU
• Format: Article
• Language: English
• Subjects: 5-HT3受体; 5-羟色胺; 分子生物学; 烟碱型乙酰胆碱受体; 离子通道; 结构生物学; 药物发现; 门控
• ISSN: 1671-4083; 1745-7254

The nicotinic acetylcholine receptors （nAChRs） and the 5-HT3 receptors （5-HT3Rs） are cation-selective members of the pentameric ligand-gated ion channels （pLGICs）, which are oligomeric protein assemblies that convert a chemical signal into an ion flux through postsynaptic membrane. They are critical components for synaptic transmission in the nervous system, and their dysfunction contributes to many neurological disorders. The diverse subunit compositions of pLGICs give rise to complex mechanisms of ligand recognition, channel gating, and ion-selective permeability, which have been demonstrated in numerous electrophysiological and molecular biological studies, and unraveled by progress in studying the structural biology of this protein family. In this review, we discuss recent insights into the structural and functional basis of two cation-selective pLGICs, the nAChR and the 5-HT3R, including their subunit compositions, ligand binding, and channel gating mechanisms. We also discuss their relevant pharmacology and drug discovery for treating various neurological disorders. Finally, we review a model of two alternative ion conducting pathways based on the latest 5-HT3A crystal structure.