Pore-opening mechanism of the nicotinic acetylcholine receptor evinced by proton transfer.

ABSTRACT: The conformational changes underlying cysteine-loop receptor channel gating remain elusive and controversial. We previously developed a single-channel electrophysiological method that allows structural inferences about the transient open-channel conformation to be made from the effect and properties of introduced charges on systematically engineered ionizable amino acids. Here we have applied this methodology to the entire M1 and M3 segments of the muscle nicotinic acetylcholine receptor, two transmembrane alpha-helices that pack against the pore-lining M2 alpha-helix. Together with our previous results on M2, these data suggest that the pore dilation that underlies channel opening involves only a subtle rearrangement of these three transmembrane helices. Such a limited conformational chan

SUBMITTER: Cymes GD 

PROVIDER: S-EPMC2596065 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature