Different gating mechanisms in glutamate receptor and K+ channels.

ABSTRACT: The basic structural features of channel gating in glutamate receptors (GluRs) remain unknown. Here we used covalent modification of substituted cysteines and fast agonist application to study the contribution of the M3 segment in AMPA receptor GluR-A subunits to channel structure and gating. The pattern of accessibility of substituted cysteines to extracellularly applied methanethiosulfonate reagents and the rates of their modification by these reagents, measured in either the presence or absence of glutamate, indicate that M3 forms an alpha-helix that lines the pore of the channel and is involved in gating-related movements. The voltage dependence of modification rates places the tip of the M2 loop (the Q/R site) close to the middle of M3. All of these results are consistent with pore-fo

SUBMITTER: Sobolevsky AI 

PROVIDER: S-EPMC6740752 | biostudies-literature | 2003 Aug

REPOSITORIES: biostudies-literature