P53 forward: 59-ATT CTG CCC TCA CAG CTC TGG CT-39; P53 reverse: 59-CCG GAG GAA GCA AAG GAA ATG G-39; P53 TaqMan: 59-FAM-CCG CAG TTT CTT CCC ATG CAC CTG-TAMRA-39. Quantitative PCRs were performed in an iCycler IQ real-time PCR Detection System (BioRad, USA), with a first denaturation step at 94uC for 10 min, followed by 45 cycles comprising denaturation at 94uC for 20 s, annealing at 58uC for 30 s and extension at 72uC for 40 s. Inputs removed before applying antibody were deployed to normalize for differences in the amount of DNA in each PCR. Dual-Luciferase Assay For luciferase analysis, 100 ng plasmid DNA and 100 ng renilla control plasmid were transfected into HeLa cells. Dual luciferase- References 1. Aravin AA, Hannon GJ, Brennecke J (2007) The Piwi-piRNA pathway provides an adaptive defense in the transposon arms race. Science 318: 761–764. 2. Zamore PD, Haley B (2005) Ribo-gnome: the big world of small RNAs. Science 309: 1519–1524. 3. 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