National Institutes of Health/National Heart, Lung, and Blood Institute (NIH/NHLBI)
R01HL145473
米国
引用
ジャーナル: Nat Commun / 年: 2024 タイトル: Structural basis for ryanodine receptor type 2 leak in heart failure and arrhythmogenic disorders. 著者: Marco C Miotto / Steven Reiken / Anetta Wronska / Qi Yuan / Haikel Dridi / Yang Liu / Gunnar Weninger / Carl Tchagou / Andrew R Marks / 要旨: Heart failure, the leading cause of mortality and morbidity in the developed world, is characterized by cardiac ryanodine receptor 2 channels that are hyperphosphorylated, oxidized, and depleted of ...Heart failure, the leading cause of mortality and morbidity in the developed world, is characterized by cardiac ryanodine receptor 2 channels that are hyperphosphorylated, oxidized, and depleted of the stabilizing subunit calstabin-2. This results in a diastolic sarcoplasmic reticulum Ca leak that impairs cardiac contractility and triggers arrhythmias. Genetic mutations in ryanodine receptor 2 can also cause Ca leak, leading to arrhythmias and sudden cardiac death. Here, we solved the cryogenic electron microscopy structures of ryanodine receptor 2 variants linked either to heart failure or inherited sudden cardiac death. All are in the primed state, part way between closed and open. Binding of Rycal drugs to ryanodine receptor 2 channels reverts the primed state back towards the closed state, decreasing Ca leak, improving cardiac function, and preventing arrhythmias. We propose a structural-physiological mechanism whereby the ryanodine receptor 2 channel primed state underlies the arrhythmias in heart failure and arrhythmogenic disorders.