FIG 6.

HPV38 E6 and E7 prevent the UV-mediated activation of TLR9 expression. (A) hTERT PHKs were transduced with an empty control vector (pLXSN) or with pLXSN encoding HPV38 E6 and E7 (HPV38E6E7) and then UVB irradiated (+) or mock irradiated (−) as described in Materials and Methods. The efficiency of transduction was verified and TLR9 mRNA levels, as well as E6 and E7 mRNA levels, were measured by RT-qPCR. (B) Normal PHKs were transduced with the empty pLXSN vector (pLXSN) or with pLXSN encoding HPV38 E6 and E7 (HPV38E6E7) and then UVB irradiated (+) or mock irradiated (−) as described in Materials and Methods. After 8 h, total RNA was extracted, and the TLR9 and viral mRNA levels were analyzed by RT-qPCR. (C) Total protein extracts from hTERT PHKs that were transduced with the empty pLXSN vector (pLXSN) or with pLXSN encoding HPV38 E6 and E7 (HPV38E6E7) and then UVB irradiated (+) or mock irradiated (−) were analyzed by immunoblotting (left panel). The quantification of protein bands in three independent experiments is shown (right panel). The error bars represent the standard deviation of three biological replicates. *, P < 0.05; **, P < 0.01; ns, not significant.