FIG 3.

p53 plays a key role in UV-mediated TLR9 transcriptional activation. (A and B) hTERT PHKs either expressing wild-type p53 (scramble) or with CRISPR/Cas9-mediated p53 deletion (crip53) were UVB irradiated (+) or mock irradiated (−). (A) Total RNA was extracted, and TLR9 and p53 mRNA levels were measured by RT-qPCR. (B) Total protein extracts were analyzed by immunoblotting for the indicated antibodies (left panel). TLR9 band intensities were quantified and normalized to β-actin levels (right panel). (C) Normal PHKs were transfected with either a control siRNA (scramble) or an siRNA specific for p53 (sip53). After 40 h, the cells were UVB irradiated (+) or mock irradiated (−) as described in Materials and Methods. Total RNA was then extracted, and p53 and TLR9 mRNA levels were measured by RT-qPCR. The RT-qPCR data shown are the means from three independent experiments. The error bars represent the standard deviations of the three biological replicates. The immunoblots shown are from one representative experiment of the three performed. **, P < 0.01; ns, not significant.