Calmodulin (CaM) regulates a variety of membrane channels in response to Ca2+, but the precise mechanisms are still unclear. Now a combination of single-particle EM, molecular dynamics simulations and functional assays is used to elucidate the structure of Ca2+–CaM bound to the full-length aquaporin AQP0, revealing a cytoplasmic gate that is closed upon CaM binding to control channel permeability in an allosteric manner.
- Steve L Reichow
- Daniel M Clemens
- Tamir Gonen
