Extended Data Fig. 2: Exo1 promotes Apollo-independent processing of telomere overhang in absence of DNA-PKcs.
From: DNA-PK and the TRF2 iDDR inhibit MRN-initiated resection at leading-end telomeres
(a), (b) Telomeric overhang assay and quantification on SV40-LT-immortalized ApolloF/F Lig4+/+ and ApolloF/F Lig4−/− MEFs 96 h after Cre-mediated deletion of endogenous Apollo for three independent experiments. Statistical analysis by two-way ANOVA. (c) Targeting of the mouse XRCC6/KU70 locus. The Xrcc6 genomic locus, the KOMP-derived targeted allele with the LacZ/Neo insert and the floxed allele are indicated. The LoxP sites are represented as triangles. (d) Immunoblots for mouse Ku70 in SV40-LT-immortalized Ku70F/+ or Ku70F/F without any treatment or 108 h after viral transduction with Hit & Run Cre as analyzed in Fig. 2e,f. (e) Quantification of leading end telomere fusions in ApolloF/F DNA-PKcs−/− MEFs 108 h after Cre-mediated deletion of endogenous Apollo and/or depletion of Exo1 for two independent experiments. Bars represent median of 20 metaphases (10 per experiment). Statistical analysis by Kruskal-Wallis one-way ANOVA for multiple comparisons. (f), (g) Telomeric overhang assay and quantification on SV40-LT-immortalized ApolloF/F DNA-PKcs−/− MEFs 108 h after Cre-mediated deletion of endogenous Apollo and/or depletion of Exo1 for four independent experiments. Statistical analysis by unpaired t-test.
