Fig. 1: Cell model for functional study of redox-sensitive cysteine residues in hRyR2.

a Representative confocal image of the HEK293 cell model for the functional studies of redox-sensitive cysteines in RyR2. Corresponding images demonstrate the cells under transmitted light and the expression of GFP-tagged hRyR2 and R-CEPIA1er [Ca²⁺]_ER sensor. The images of co-localized GFP-tagged RyR2 and R-CEPIA1er were obtained for corresponding HEK293 cells in all confocal experiments mentioned in this paper. b Representative recordings of Ca²⁺ waves generated by hRyR2 in HEK293 cells. Diamide was added to induce hRyR2 oxidation and cross-linking. Caffeine (Caf; 10 mM) and ionomycin (2 µM) in 10 mM Ca²⁺ were used to normalize the signal. The dashed line indicates the level of ER Ca²⁺ load. c Western blot of the disulfide cross-linking of hRyR2 caused by increasing concentrations of diamide. DTT (100 mM) was added to the samples to reverse hRyR2 oxidation and cross-linking (data representative of 3 independent experiments).