Fig. 1: Cryo-EM maps of RyR2 reveal CaM binding to RyR2.

Ca-free (apo) and Ca-bound -states of CaM bind at distinct locations. A RyR2 (green) in a closed-pore state with FKBP12.6 (Light Blue) and apo-CaM (Purple) under EGTA conditions (< 0.2 nM Ca²⁺)⁴. B RyR2 in a closed-pore state with Ca-CaM bound at 20 μM Ca^2+,4.