Fig 5.

γH2AX associates with HPV genomes. Chromatin immunoprecipitation (ChIP) assays were performed on CIN 612 cells that were harvested at T₀ or after 72 h of differentiation in high-calcium medium, as previously described by Wong et al. (42). Immunoprecipitations were performed using an antibody to phospho-H2AX Ser139 (γH2AX) (Millipore). Quantitative PCR was done using a Roche Lightcycler 480 Sybr green master kit (Roche Applied Sciences). The primers used were specific to the upstream regulatory region (URR) of HPV31. Forward, 5′ AAC TGC CAA GGT TGT GTC ATG C 3′; reverse, 5′ TGG CGT CTG TAG GTT TGC AC 3′.The data are expressed as fold activation over the control mouse IgG (Santa Cruz), where the fold level was set at 1 to allow for comparisons. Ca, calcium. Shown is a representative of two experiments.