Figure 3.

MCU silencing reduces mitochondrial Ca²⁺ transport. (a) MCU mRNA expression by semiquantitative qRT-PCR in silenced cardiomyocytes, ^∗∗∗P < 0.001 versus siRNA-Neg, mean ± SEM, n = 7. (b) MCU protein expression, with β-actin used as a loading control. ^∗∗∗P < 0.001 versus siRNA-Neg, mean ± SEM, n = 6. (c) Representative traces of mitochondrial Ca²⁺ uptake in permeabilized MCU-silenced cardiomyocytes using CG-5N Ca²⁺ indicator after 15 μM Ca²⁺ addition. The experiment was performed in the presence of 1 μM CsA. AFU, arbitrary fluorescence units. (d) Time to 50% decay analysis (T_50%) of mitochondrial Ca²⁺ transport. ^∗P < 0.05 versus siRNA-Neg, mean ± SEM, n = 6. MCU silencing conditions were using 225 nM of siRNA-MCU at 96 h of transfection.