Figure 4.

MiR-532-3p participates in the regulation of ARC expression. (a) Analysis of ARC 3′UTR potential binding site for miR-532-3p by RNAhybrid. Potential complementary residues are shown in red. (b) The miR-532-3p levels in neonatal rat cardiomyocytes treated with 2 μM DOX at the indicated time. *P<0.05 versus control (untreated). (c) MiR-532-3p levels in mice administered with DOX or saline as described in Materials and Methods. n=5 mice per group. (d) ARC mRNA and protein levels in neonatal rat cardiomyocytes overexpressing miR-532-3p by transfecting with miR-532-3p mimics. (e) Kncokdown of endogenous miR-532-3p by transfecting its antagomirs attenuated decrease of ARC mRNA and protein levels upon DOX (2 μM) for 12 h in cardiomyocytes. (f) Luciferase activity detected in HEK-293 transfected with synthesized miR-532-3p mimic or mimic control, along with luciferase reporter constructs as indicated. (g) Luciferase activity of luciferase construct ARC 3′UTR-Wt is decreased upon DOX treatment in cardiomyocytes. Data are expressed as the mean±S.D., n=3 except in panel (c). *P<0.05