Figure 2: siRNA-mediated knockdown of autophagy restores Δ133p53α expression. | Nature Communications

Figure 2: siRNA-mediated knockdown of autophagy restores Δ133p53α expression.

From: Autophagic degradation of the inhibitory p53 isoform Δ133p53α as a regulatory mechanism for p53-mediated senescence

Figure 2

(a–c) Knockdown of pro-autophagic proteins restores Δ133p53α expression. MRC-5 fibroblasts at late-passage (PDLs 51) were transfected with three independent siRNA oligonucleotides (lanes 1–3) against ATG5 (a), ATG7 (b) and Beclin-1 (c), along with their control siRNA (lane C), for 4 days. Knockdown of ATG5 was confirmed by the loss of ATG5–ATG12 conjugate (detected by anti-ATG5 antibody). Knockdown of the other two proteins was confirmed using the corresponding antibodies. Δ133p53α, full-length p53 and LC3B (LC3-I and LC3-II) were examined in all samples. The relative expression levels of Δ133p53α and full-length p53 (normalized with β-actin) are shown below the images. (d) Knockdown of pro-autophagic proteins and treatment with bafilomycin A1 show similar effects on Δ133p53α and p62/SQSTM1. MRC-5 fibroblasts at late-passage (PDLs 51) were transfected with control siRNA (c), ATG5 siRNA (A5, no. 1 in a), ATG7 siRNA (A7, no. 1 in b) and Beclin-1 siRNA (B1, no. 2 in c) as in a–c, untreated (−) or treated with bafilomycin A1 (+, 100 nM for 4 h), and examined in immunoblots for indicated proteins. The relative expression levels of Δ133p53α and p62/SQSTM1 (normalized with β-actin) are shown below the images.

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