Extended Data Figure 6: Acetylated protein VII spectra from virus particles and analysis of total histone PTM changes upon protein VII expression.
From: A core viral protein binds host nucleosomes to sequester immune danger signals
a, Liquid chromatography-mass spectrometry (LC-MS) analysis of unmodified and modified chymotryptic peptide AKKRSDQHPVRVRGHY. On the left, nano-LC-MS-extracted ion chromatograms of protein VII peptides identified in the histone extracts of adenovirus infected cells (Inf) or viral particles (VP). The top left represents the modified form, while the bottom left represents the unmodified form. Non-modified forms were detected in both conditions for Inf and VP, while the acetylated form was unique for the infected sample only (Inf). On the right, full MS spectrum of the modified (top) and unmodified (bottom) peptide. Circled mass represents the monoisotopic signal of the peptide. b, Summary of post-translational modifications detected on protein VII. Peptides shown were identified during infection at various time points with the mature protein VII in the top row and preVII in the bottom row. The numbers in brackets for preVII indicate the location of the same moiety in mature protein VII. Acetylation sites were detected in approximately 3% of peptides for mature protein VII and 2% of peptides in preVII. Phosphorylation was detected in approximately 1% of peptides for mature protein VII and preVII. c, d, Quantification of histone H3 (c) and H4 (d) PTMs in protein-VII–HA-induced (+dox) and -uninduced (−dox) A549 cells from the analysis of crude histone mixtures (n = 3 biological replicates). Positions of PTMs are listed along the x axis. Modification type is indicated by colour as shown. y Axis represents the cumulative extent of PTMs relative to the total histone H3 or H4, respectively. e, Breakdown of the histone marks (H3K14ac, H3K27me1, H3K36me3, H4K20me1, H4K20me2 and H4K20me3) found to be significantly different (n = 3 biological replicates) in terms of relative abundance between the protein-VII–HA-induced and -uninduced states (<5% homoscedastic two-tailed t-test). Mean ± s.d.
