Biophysical and molecular mechanisms of Shaker potassium channel inactivation.
The potassium channels encoded by the Drosophila Shaker gene activate and inactivate rapidly when the membrane potential becomes more positive. Site-directed mutagenesis and single-channel patch-clamp recording were used to explore the molecular transitions that underlie inactivation in Shaker potassium channels expressed in Xenopus oocytes. A region near the amino terminus with an important role in inactivation has now been identified. The results suggest a model where this region forms a cytoplasmic domain that interacts with the open channel to cause inactivation.
Hoshi
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Department of Molecular and Cellular Physiology, Stanford University, School of Medicine, CA 94305.
Zagotta
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Aldrich
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D000595:Amino Acid Sequence; D000818:Animals; D004247:DNA / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D004553:Electric Conductivity; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology*; D007700:Kinetics; D008564:Membrane Potentials / Q000502:physiology; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016297:Mutagenesis, Site-Directed; D009865:Oocytes / Q000378:metabolism; D015221:Potassium Channels / Q000235:genetics / Q000502:physiology*; D012326:RNA Splicing; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000494:pharmacology; D014981:Xenopus
D015221:Potassium Channels; D004247:DNA; D014357:Trypsin