Ion channels are pore-forming proteins and their function is to facilitate the diffusion of ion across cell membranes by flow of ions down the electrochemical gradient. Voltage-gated ion channels are a class of transmembrane ion channels and are found throughout the body which allowed a rapid and coordinated depolarization in response to voltage change in excitable cells (Catterall, 2010). Rece...

Despite tremendous progress in the study of voltage-gated channels, the molecular mechanism underlying voltage sensing has remained a matter of debate. We review five new studies that make major progress in the field. The studies employ a battery of distinct approaches that have the common aim of measuring the motion of the voltage sensor. We interpret the results in light of the recent crystal...

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 ...

Voltage-gated ion channels open in response to a change in membrane potential. The "sensor," or the channel's molecular entity responsible for the detection of voltage change, is formed by a transmembrane element, rich with basic residues, called the "voltage sensor" or the "S4 domain." The movement of the S4 drives a global conformational change leading to the opening of the permeation pathway...

KCNE1 is a single-transmembrane protein of the KCNE family that modulates the function of voltage-gated potassium channels, including KCNQ1. Hereditary mutations in KCNE1 have been linked to diseases such as long QT syndrome (LQTS), atrial fibrillation, sudden infant death syndrome, and deafness. The transmembrane domain (TMD) of KCNE1 plays a key role in mediating the physical association with...

Voltage-sensor (VS) domains cause the pore of voltage-gated ion channels to open and close in response to changes in transmembrane potential. Recent experimental studies suggest that VS domains are independent structural units. This independence is revealed dramatically by a voltage-dependent proton-selective channel (Hv), which has a sequence homologous to the VS domains of voltage-gated potas...