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Gating the pore of P2X receptor channels.

ABSTRACT: Three families of ligand-activated ion channels mediate synaptic communication between excitable cells in mammals. For pentameric channels related to nicotinic acetylcholine receptors and tetrameric channels such as glutamate receptors, the pore-forming and gate regions have been studied extensively. In contrast, little is known about the structure of trimeric P2X receptor channels, a family of channels that are activated by ATP and are important in neuronal signaling, pain transmission and inflammation. To identify the pore-forming and gate regions in P2X receptor channels, we introduced cysteine residues throughout the two transmembrane (TM) segments and studied their accessibility to thiol-reactive compounds and ions. Our results show that TM2 lines the central ion-conduction pore, TM1 is positioned peripheral to TM2 and the flow of ions is minimized in the closed state by a gate formed by the external region of TM2.

SUBMITTER: Li M

PROVIDER: S-EPMC2629452 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Gating the pore of P2X receptor channels.

Li Mufeng M Chang Tsg-Hui TH Silberberg Shai D SD Swartz Kenton J KJ

Nature neuroscience 20080629 8

Three families of ligand-activated ion channels mediate synaptic communication between excitable cells in mammals. For pentameric channels related to nicotinic acetylcholine receptors and tetrameric channels such as glutamate receptors, the pore-forming and gate regions have been studied extensively. In contrast, little is known about the structure of trimeric P2X receptor channels, a family of channels that are activated by ATP and are important in neuronal signaling, pain transmission and infl ...[more]

PMID: 18587390

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