Fig. 7.

CaMKII activation via S280 O-GlcNAcylation regulates I_K1 and I_to recovery in hyperglycemia. a Representative voltage-gated K⁺ currents and I_K1 traces in normoglycemia and hyperglycemia in CaMKIIδ-knockout (KO), overexpression (OE) and O-GlcNAc-resistant S280A knock-in mouse myocytes. b–j K⁺ current remodeling in CaMKIIδ-KO and OE in normoglycemia. CaMKIIδ-S280A had a normal baseline phenotype. Hyperglycemia effects on I_to recovery kinetics (f, g) and I_K1 (h, i) but not on I_to amplitude (b) were prevented in both CaMKIIδ-KO and S280A. Two-way ANOVA; *p < 0.05, **p < 0.01, ***p < 0.001 vs. normoglycemia; ^†p < 0.05, ^††p < 0.01, ^†††p < 0.001 vs. WT control