Structural Determinants of Gating in Inward-Rectifier K+ Channels
نویسندگان
چکیده
منابع مشابه
Carboxy-terminal Determinants of Conductance in Inward-rectifier K Channels
Previous studies suggested that the cytoplasmic COOH-terminal portions of inward rectifier K channels could contribute significant resistance barriers to ion flow. To explore this question further, we exchanged portions of the COOH termini of ROMK2 (Kir1.1b) and IRK1 (Kir2.1) and measured the resulting single-channel conductances. Replacing the entire COOH terminus of ROMK2 with that of IRK1 de...
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Hypercholesterolemia is an independent risk factor for development of cardiovascular disease1 and has been demonstrated to impair endothelium-dependent and independent vasodilatation.2 However, the mechanisms responsible for changes in vascular reactivity and impaired blood flow regulation induced by hypercholesterolemia remain unclear. Previous studies in cultured endothelial cells have shown ...
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Cation channel gating may occur either at or below the inner vestibule entrance or at the selectivity filter. To differentiate these possibilities in inward rectifier (Kir) channels, we examined cysteine accessibility in the ATP-gated Kir6.2 channel. MTSEA and MTSET both block channels and modify M2 cysteines with identical voltage dependence. If entry is restricted to open channels, modificati...
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Ion channels play an important role in cellular functions, and specific cellular activity can be produced by gating them. One important gating mechanism is produced by intra- or extracellular ligands. Although the ligand-mediated channel gating is an important cellular process, the relationship between ligand binding and channel gating is not well understood. It is possible that ligands are inv...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 1999
ISSN: 0006-3495
DOI: 10.1016/s0006-3495(99)77357-1