Extended Data Fig. 4: Proteomic identification and abundance of H4K5acme in cells.
From: Acetyl-methyllysine marks chromatin at active transcription start sites
a, Extracted ion chromatograms for targeted ions from histones extracted from HEK293T cells (endogenous, m/z 775.9543), the isotopically labelled synthetic H4K5acme peptide (m/z 780.9857), and their mixture. b, MS spectra for the extracted ion chromatograms in a. c, Extracted ion chromatograms of diagnostic ion 157.1335 for H4K5acme from a synthetic standard (left) and endogenous HEK293T histones (right). d-h, MS/MS spectra of endogenous targeted peptides. See Table S2 for target ions and Tables S5–S7 for calculated and observed y- and b-ions. i, Standard curves of extracted ion chromatogram peak areas of diagnostic ions for synthetic H4K5acme (270.1812 and 157.1335) and H4Kpr (140.1070) peptide standards. Points show the mean for three independent replicates, and error bars show standard deviation. Note that peptides were processed with standard propionylation methods. d10 indicates peptide isotopically labeled with deuterated leucine.
