Download MendeleyPotassium dependent structural changes in the selectivity filter of HERG potassium channels.
Lau, C.H.Y., Flood, E., Hunter, M.J., Williams-Noonan, B.J., Corbett, K.M., Ng, C.A., Bouwer, J.C., Stewart, A.G., Perozo, E., Allen, T.W., Vandenberg, J.I.(2024) Nat Commun 15: 7470-7470
- PubMed: 39209832
- DOI: https://doi.org/10.1038/s41467-024-51208-w
- Primary Citation of Related Structures:
9CHP, 9CHQ, 9CHR, 9CHS - PubMed Abstract:
The fine tuning of biological electrical signaling is mediated by variations in the rates of opening and closing of gates that control ion flux through different ion channels. Human ether-a-go-go related gene (HERG) potassium channels have uniquely rapid inactivation kinetics which are critical to the role they play in regulating cardiac electrical activity. Here, we exploit the K + sensitivity of HERG inactivation to determine structures of both a conductive and non-conductive selectivity filter structure of HERG. The conductive state has a canonical cylindrical shaped selectivity filter. The non-conductive state is characterized by flipping of the selectivity filter valine backbone carbonyls to point away from the central axis. The side chain of S620 on the pore helix plays a central role in this process, by coordinating distinct sets of interactions in the conductive, non-conductive, and transition states. Our model represents a distinct mechanism by which ion channels fine tune their activity and could explain the uniquely rapid inactivation kinetics of HERG.
Organizational Affiliation:
Mark Cowley Lidwill Research Program, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.
