Direct Physical Measure of Conformational Rearrangement Underlying Potassium Channel Gating

作者：Lidia M. Mannuzzu, Mario M. Moronne, Ehud Y. Isacoff · 发表于：Science · 年份：1996 · DOI：10.1126/science.271.5246.213 · 被引用次数：616 · 研究领域：Ion channel regulation and function、Neuroscience and Neural Engineering、Electrochemical Analysis and Applications

In response to membrane depolarization, voltage-gated ion channels undergo a structural rearrangement that moves charges or dipoles in the membrane electric field and opens the channel-conducting pathway. By combination of site-specific fluorescent labeling of the Shaker potassium channel protein with voltage clamping, this gating conformational change was measured in real time. During channel activation, a stretch of at least seven amino acids of the putative transmembrane segment S4 moved from a buried position into the extracellular environment. This movement correlated with the displacement of the gating charge, providing physical evidence in support of the hypothesis that S4 is the voltage sensor of voltage-gated ion channels.