The pore helix is involved in stabilizing the open state of inwardly rectifying K+ channels.

ABSTRACT: Ion channels can be gated by various extrinsic cues, such as voltage, pH, and second messengers. However, most ion channels display extrinsic cue-independent transitions as well. These events represent spontaneous conformational changes of the channel protein. The molecular basis for spontaneous gating and its relation to the mechanism by which channels undergo activation gating by extrinsic cue stimulation is not well understood. Here we show that the proximal pore helix of inwardly rectifying (Kir) channels is partially responsible for determining spontaneous gating characteristics, affecting the open state of the channel by stabilizing intraburst openings as well as the bursting state itself without affecting K(+) ion-channel interactions. The effect of the pore helix on the open state

SUBMITTER: Alagem N 

PROVIDER: S-EPMC1303086 | biostudies-literature | 2003 Jul

REPOSITORIES: biostudies-literature