Fig. 6: XPF acetylation facilitates XPF-ERCC1 complex assembly.

a XPF-SFB knock-in cells were lysed and subjected to immunoprecipitation. Lysates were adjusted on the basis of XPF and ERCC1 protein levels. The amount of co-immunoprecipitated ERCC1 was quantified by ImageJ and normalized to immunoprecipitated XPF. Data represent means ± SEM from three independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001, One-way ANOVA with Dunnett’s Multiple Comparison test. b XPF and ERCC1 levels were quantified by ImageJ. Data represent means ± SEM from three independent experiments. ***P < 0.001, Two-way ANOVA with Bonferroni post-tests. c, d HeLa cells were treated with MG149 (100 μM) or NU9056 (20 μM) or infected with SIRT1 shRNAs. Data represent means ± SEM from three independent experiments. ***P < 0.001, Two-way ANOVA with Bonferroni post-tests. e The amount of co-immunoprecipitated ERCC1 was quantified by ImageJ and normalized to immunoprecipitated XPF. Data represent means ± SEM from three independent experiments. ns not significant, ***P < 0.001, One-way ANOVA with Bonferroni’s Multiple Comparison test. f Arrangement of XPF-ERCC1 residues near Lys911 based on NMR structure (PDB:1z00, model01). XPF is shown in cyan, ERCC1 is shown in pink, gray dashed lines indicate the distance (2.8 Å) between the ε-nitrogen atom in Lys911 and the carbonyl oxygen atom in Glu907. The numbering in the NMR structure is off by 11 compared with the sequence used in this study (shown in parentheses). Figure was generated by the PyMOL Molecular Graphics System (Version 2.1.0 Open-Source) (Http://www.pymol.org). g, h The amount of co-immunoprecipitated ERCC1 was quantified by ImageJ and normalized to immunoprecipitated XPF. Data represent means ± SEM from three independent experiments. ns not significant, **P < 0.01, ***P < 0.001, One-way ANOVA with Bonferroni’s Multiple Comparison test. i Nonacetylated or acetylated peptides were conjugated to Sepharose beads and incubated with HEK293T cell lysates. j The amount of co-immunoprecipitated XPF was quantified by ImageJ and normalized to immunoprecipitated ERCC1. Data represent means ± SEM from three independent experiments. ns not significant, **P < 0.01, ***P < 0.001, One-way ANOVA with Bonferroni’s Multiple Comparison test. Source data are provided as a Source Data file.