Extended Data Figure 2: Protein VII associates tightly with chromatin and binds DNA and nucleosomes in vitro.
From: A core viral protein binds host nucleosomes to sequester immune danger signals
a, Western blot analysis showing protein VII in histone extracts from infected HeLa cells at 24 hpi. b, Chromatin fractionation of lysates from A549 cells that were uninfected (mock) or infected for 24 h with Ad5. Viral and cellular proteins were detected by western blotting with various antibodies as indicated. c, Agarose gel analysis of DNA extracted from nuclear fractionation experiments, indicating that the size of DNA is between 100 and 200 bp and elutes predominantly in the higher-salt fractions. d, Chromatin fractionation of cells induced to express protein VII, indicating that protein VII is present in the highest-salt fraction from the first day of induction. e, f, Recombinant protein-VII–His binds DNA. Incubating increasing molar amounts of protein VII with 195 bp DNA results in shifts by native gel electrophoresis, indicating protein-VII–DNA complex formation. Staining with either ethidium bromide (e) or Coomassie (f) are shown to verify the presence of DNA and protein, respectively. g, Ethidium bromide staining shows DNA content of nucleosome shifts from gel in Fig. 1f.
