Metal-driven operation of the human large-conductance voltage- and Ca2+-dependent potassium channel (BK) gating ring apparatus.

ABSTRACT: Large-conductance voltage- and Ca(2+)-dependent K(+) (BK, also known as MaxiK) channels are homo-tetrameric proteins with a broad expression pattern that potently regulate cellular excitability and Ca(2+) homeostasis. Their activation results from the complex synergy between the transmembrane voltage sensors and a large (>300 kDa) C-terminal, cytoplasmic complex (the "gating ring"), which confers sensitivity to intracellular Ca(2+) and other ligands. However, the molecular and biophysical operation of the gating ring remains unclear. We have used spectroscopic and particle-scale optical approaches to probe the metal-sensing properties of the human BK gating ring under physiologically relevant conditions. This functional molecular sensor undergoes Ca(2+)- and Mg(2+)-dependent conformational

SUBMITTER: Javaherian AD 

PROVIDER: S-EPMC3121532 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature