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-Structure paper
Title | Structural mechanism of two gain-of-function cardiac and skeletal RyR mutations at an equivalent site by cryo-EM. |
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Journal, issue, pages | Sci Adv, Vol. 6, Issue 31, Page eabb2964, Year 2020 |
Publish date | Jul 29, 2020 |
Authors | Kavita A Iyer / Yifan Hu / Ashok R Nayak / Nagomi Kurebayashi / Takashi Murayama / Montserrat Samsó / |
PubMed Abstract | Mutations in ryanodine receptors (RyRs), intracellular Ca channels, are associated with deadly disorders. Despite abundant functional studies, the molecular mechanism of RyR malfunction remains ...Mutations in ryanodine receptors (RyRs), intracellular Ca channels, are associated with deadly disorders. Despite abundant functional studies, the molecular mechanism of RyR malfunction remains elusive. We studied two single-point mutations at an equivalent site in the skeletal (RyR1 R164C) and cardiac (RyR2 R176Q) isoforms using ryanodine binding, Ca imaging, and cryo-electron microscopy (cryo-EM) of the full-length protein. Loss of the positive charge had greater effect on the skeletal isoform, mediated via distortion of a salt bridge network, a molecular latch inducing rotation of a cytoplasmic domain, and partial progression to open-state traits of the large cytoplasmic assembly accompanied by alteration of the Ca binding site, which concur with the major "hyperactive" feature of the mutated channel. Our cryo-EM studies demonstrated the allosteric effect of a mutation situated ~85 Å away from the pore and identified an isoform-specific structural effect. |
External links | Sci Adv / PubMed:32832689 / PubMed Central |
Methods | EM (single particle) |
Resolution | 3.27 - 5.1 Å |
Structure data | EMDB-21860, PDB-6wot: EMDB-21861, PDB-6wou: EMDB-21862, PDB-6wov: |
Chemicals | ChemComp-ZN: |
Source |
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Keywords | TRANSPORT PROTEIN/ISOMERASE / Ryanodine receptor / Calcium channel / Mutation / NTDA mutation / RyR1 / malignant hyperthermia / central core disease / TRANSPORT PROTEIN-ISOMERASE complex / RyR2 / Polymorphic catecholergic ventricular tachycardia / Arrhythmogenic Right Ventricular Dysplasia 2 / CICR / excitation-contraction coupling |