UV-induced mutagenesis in inducible genes. (A) Mutagenesis in the transcribed strand of the Cyclin D2 gene. Top left, Detection of a mutated fragment of 203 bp in nonirradiated and UV-irradiated cells. Bottom left, Calibration curve for the 282-bp control fragment. Right, Quantification of mutation frequency on the basis of the calibration curve. Data are representative of 3 distinct experiments (n = 12 donors) and shown as mean ± SEM. (B) Mutagenesis in the transcribed strand of the BCL6 gene in cells irradiated or not irradiated with 5 J/m2 UV. Top left, A 54-bp mutated fragment was strongly amplified in UV-irradiated primary B lymphocytes (n = 10 donors) but not in WT or XP-E lymphoblasts. Bottom left, Calibration curve for the 180-bp control fragment. Right, Densitometric quantification of ethidium bromide-stained bands. Mutation frequency was not calculated because of the significant difference in sizes between the mutated fragment and the positive control. Data are representative of 3 distinct experiments, and shown as mean ± SEM.
