B U2OS wild‐type (WT) and USP45 knockout (KO) cells were irradiated with UV‐C (20 J/m2). At the indicated post‐irradiation times, genomic DNA was extracted and subjected to Southern dot blot analysis using antibodies recognising CPD and dsDNA total antibody. Data are shown from a triplicate experiment in which each blot is derived from independent cells. 