Figure 4

Effect of Perk knockdown on membrane transporter expression under ER stress preconditioning. NS, non-silencing. (A) RT-qPCR analysis of Perk mRNA. Total RNA was extracted from untreated cells or following treatment with 0.3 μg/ml TPG for 16 h. The histogram depicts Perk mRNA normalized to Actb mRNA represented as the fold increase over non-pretreated controls. Values shown are the means ± SE of 3 separate experiments. ***Significantly different from TPG-untreated cells by a one-way ANOVA (here p < 0.001). ^###Significantly different from TPG-treated NS siRNA-transfectants by a one-way Welch’s t-test (here p < 0.001). (B) Synthetic siRNA-mediated knockdown of Perk. Western blots of C2C12-DMPK160 cells transfected with NS siRNA or Perk siRNA were analyzed using the indicated antibody probes. Cropped blots are shown; all gels were run under the same experimental conditions. (C–E) RT-qPCR analysis of membrane transporter (C), Snhg1 (D), or Atf4 (E) mRNA. NS, non-silencing. Total RNA was extracted from untreated cells or following treatment with 0.3 μg/ml TPG for 16 h. The histogram depicts the indicated mRNA normalized to Actb mRNA, represented as the fold increase over non-pretreated controls. Values shown are the means ± SE of 3 separate experiments. *^, **^, ***Significantly different from TPG-untreated cells by a one-way ANOVA (*p < 0.05, **p < 0.01, ***p < 0.001). ^{#, ##, ###}Significantly different from TPG-treated NS siRNA-transfectants by a one-way Welch’s t-test (^#p < 0.05, ^##p < 0.01, ^###p < 0.001).