Research Paper Volume 8, Issue 3 pp 484—505

Figure 2. Selective upregulation of SIRT4 expression among the mitochondrial SIRT isoforms in cellular models of stress-induced premature senescence. (A) Increased SIRT4 mRNA levels in MCF7 cells driven into premature senescence through shRNA-mediated depletion of the centrosomal protein TACC3 [22] (analysis on day 4 upon doxycycline treatment which induces control or TACC3 shRNA expression; mean ± s.d. from three independent experiments). (B) Upregulation of SIRT4 mRNA levels in MCF7 cells 2, 4 and 6 days following γ-irradiation (single dose of 20 Gy; mean ± s.d. from three independent experiments). mRNA levels were determined by quantitative real-time polymerase chain reaction. To evaluate statistical significance, ANOVA SNK were performed (***p<0.001).