Fig. 1. ORF8 associates with chromatin.

a, ORF8 contains an ARKS motif at amino acid 50 that matches the histone H3 tail. b, Lamin A/C staining of HEK293T cells transfected to express Strep–ORF8. c, ORF8 and lamin A/C staining of SARS-CoV-2-infected A549^ACE2 cells at MOI = 1, 48 h after infection. d, Sequential salt extraction of HEK293T cells expressing ORF8 or ORF8^ΔARKSAP. e, Gene tracks for ORF8 ChIP–seq normalized to input controls. f, Targeted mass spectrometry analysis of trypsin-digested ORF8 showing that ORF8 is acetylated at lysine 52. The intact peptide or precursor at 879.9508 m/z with a 2+ charge was isolated and fragmented. Tandem mass spectrometry spectra show unfragmented precursor (green) with matching product ions within a mass error of 10 ppm. Fragment intensity is relative to that for the ion with the highest intensity across the m/z range. The colour, letter and number for each fragment indicate the sequence that fragment contains within the larger peptide (top). y (red) and b (blue) fragments indicate C- and N-terminus-matched fragments, respectively. g, ORF8 expression results in decreased levels of KAT2A. Scale bars, 10 μm. For gel source data, see Supplementary Fig. 1b,l.