RYR2 and atrial fibrillation: Similarly, mutations in RyR2 and its interacting proteins (e. g., calmodulin, calsequestrin 2, and junctophilin 2) have been identified that disrupt the interaction with these stabilizing regulators, promoting aberrant RyR2 gating and predisposing patients to catecholaminergic polymorphic ventricular tachycardia and/or familial atrial fibrillation (AF; [1, 30, 31]).