The article by Bukauskas et al. (2002) in this issue of The Journal addresses several key issues in the structure–function of connexin channels, and suggests a structural link between voltage-sensitive gating and the charge in the pore. Previous work on connexin32 (Cx32) noted a correlation between the sign of voltage-sensing charges and the rectification of the subconductance state induced by movement of those charges. The present work investigates in detail the permeability properties of the subconductance state induced by voltage in channels composed of connexin43 (Cx43). The results impart generality to an intriguing structural relationship between voltage-dependent gating and modulation of pore charge selectivity. They also show how the single-channel gating physiology may relate to the molecular signaling function of connexin channels.
The importance of electrical and molecular signaling through connexin channels is widely recognized. An increasingly detailed functional and structural picture of connexin channels...
