Download MendeleyInfluence of Lipid Mimetics on Gating of Ryanodine Receptor.
Willegems, K., Efremov, R.G.(2018) Structure 26: 1303-1313.e4
- PubMed: 30078641
- DOI: https://doi.org/10.1016/j.str.2018.06.010
- Primary Citation of Related Structures:
6FG3, 6FOO - PubMed Abstract:
Understanding gating principles of ion channels at high resolution is of great importance. Here we investigate the conformational transition from closed to open state in ryanodine receptor 1 (RyR1) reconstituted into lipid nanodiscs. RyR1 is a homotetrameric giant ion channel that couples excitation of muscle cells to fast calcium release from the sarcoplasmic reticulum. Using single-particle cryo-EM we show that RyR1 reconstituted into lipid nanodiscs is stabilized in the open conformation when bound to the plant toxin ryanodine, but not in the presence of its physiological activators, calcium and ATP. Further, using ryanodine binding assays we show that membrane mimetics influence RyR1 transition between closed and open-channel conformations. We find that all detergents, including fluorinated detergents added to nanodiscs, stabilize closed state of RyR1. Our biochemical results correlate with available structural data and suggest optimal conditions for structural studies of RyR1 gating.
Organizational Affiliation:
Center for Structural Biology, Vlaams Instituut voor Biotechnologie, 1050 Brussels, Belgium; Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
