Fig. 5

DOT1L/methylated H3K79 is involved in NER on UVB-induced DNA damage through interacting with XPC. a Melanomas from Queensland, Australia were irradiated with different doses of UVB. Cell viability was measured by MTT assay 24 h after UVB irradiation. b HPMs with stable shDOT1L or shControl were irradiated with different doses of UVB as indicated. Cell viability was measured by MTT assay 24 h after UVB irradiation. c WT or different DOT1L mutants as indicated was introduced into HPMs with stable shDOT1L expression. The resulting cells were irradiated with different doses of UVB as indicated. Cell viability was measured by MTT assay 24 h after UVB irradiation. d–f Melanomas from Queensland, Australia (d), HPMs with stable shDOT1L expression (e), or HPMs with stable shDOT1L expression and WT or different mutant DOT1L reintroduction (f) were irradiated with 100 J m⁻² UVB and then collected at different time points as indicated after UVB irradiation. Genomic DNA was extracted and photoproducts were detected. g, h HPM cells treated with EPZ-5676 or vehicle control (g) or DOT1L depletion or shControl (h) were subjected to 100 J m⁻² UVB under 5 µm micropore filter and were co-stained for CPD and XPC after 0.5 h. Scale bar, 20 μm. i The whole-cell extracts from HPM subjected to 100 J m⁻² UVB were prepared for Co-IP assay to test the interaction of DOT1L with XPC. j The whole-cell extracts from HPM subjected to 100 J m⁻² UVB were prepared for Co-IP assay to test the interaction of XPC with H3K79me2. k HPMs with DOT1L depletion or shControl were exposed to 100 J m⁻² UVB. After 0.5 h, the chromatin fraction was prepared for western blot. *p < 0.05, **p < 0.01, ***p < 0.001, unpaired Student’s t-test. Error bars represent ± s.d.