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.
Original language | English |
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Pages (from-to) | 883-887 |
Number of pages | 5 |
Journal | Nature Neuroscience |
Volume | 11 |
Issue number | 8 |
DOIs | |
State | Published - 1 Aug 2008 |
Externally published | Yes |
ASJC Scopus subject areas
- Neuroscience (all)