Quantitative comparison of selected histone PTMs in euchromatin (d0-labeled) and heterochromatin (d5-labeled).

(a.) Full mass spectrum for the 2+ charge state of an intrinsically unmodified H3.1 peptide (aa 41–49), (b.) Full mass spectrum for the 2+ charge state of a monoacetylated H3.1 peptide (aa 18–26, H3K18), (c.) Full mass spectrum for the 3+ charge state of the H3.1 dimethylated peptide (aa 27–40, H3K36), (d.) Full mass spectrum for the 2+ charge state of a diacetylated H4 peptide (aa 4–17) Labels specify the fraction represented by each peak. m/z values are indicated for each peak.