Figure 8. Inhibition of UV lesion removal from chromatin.
(A) Untreated or formaldehyde-treated cells (75 μM, 18 h) were exposed to UV light (10 J/m2) and collected immediately after irradiation or following 3-h repair incubations. Genomic DNA was isolated and analyzed for UV lesions using antibodies against 6-4PPs. (B) Quantification of three independent experiments demonstrating that 6-4PP excision is diminished by 75-μM formaldehyde exposure (error bar, S.D.). The asterisk (*p<0.05) denotes significantly reduced excision in formaldehyde-treated cells compared to the untreated control. (C) Quantification of three independent experiments demonstrating that CPD excision is also inhibited. The asterisks (*p<0.05) denote the significantly reduced excision in 75-μM formaldehyde-treated cells compared to untreated controls.