CAMK2G and Paroxysmal atrial fibrillation: In paroxysmal AF increased RyR open probability appears to arise from phosphorylation at the CaMKII site whereas results regarding phosphorylation at the PKA site are mixed (Chelu et al., 2009; Wakili et al., 2010; Chiang et al., 2014b; Li et al., 2014; Voigt et al., 2014; Lugenbiel et al., 2015).