A plant Shaker-like K+ channel switches between two distinct gating modes resulting in either inward-rectifying or 'leak' current

Among the Shaker-like plant potassium channels, AKT2 is remarkable because it mediates both instantaneous 'leak-like' and time-dependent hyperpolarisa tion-activated currents. This unique gating behaviour has been analysed in Xenopus oocytes and in COS and Chinese hamster ovary cells. Whole-cell and single-channel data show that (i) AKT2 channels display two distinct gating modes, (ii) the gating of a given AKT2 channel can change from one mode to the other and (iii) this conversion is under the control of post-translati onal factor(s). This behaviour is strongly reminiscent of that of the KCNK2 channel, recently reported to be controlled by its phosphorylation state. (C) 2001 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies.