Analysis of p53 knockdown PC12 cell lines. A) RT-PCR and immunoblot depicting levels of p53 mRNA and protein in wild-type naïve PC12 cells compared to 7-day NGF (50 ng/mL) differentiated wild-type and anti-p53 shRNA expressing PC12 cells. GAPDH mRNA levels serve as loading control for RT-PCR, while actin serves as immunoblot loading control. p53 and GAPDH mRNA levels in each sample were quantitated using ImageJ and normalized to naïve RNA levels, depicted under each band. PCR cycle number used is shown on right of gel image. p53 RNA and protein levels (and knockdown efficiency) were lowest in p53#3low cells, followed by p53#2mid and p53#4mid cell lines. B) Representative image of wild-type and p53#3low PC12 cells following 3 days treatment with 50 ng/mL NGF.