Explorative analysis of noncanonical methylation sites.A, number of methyl-sites detected upon the reanalysis of the input MS data, grouped by residue. B, Gene Ontology terms, pathways, and complexes significantly enriched among proteins bearing methylations on non-K/R residues. C, UpSets plot representation of the co-occurrence of methylated residues on different proteins. D, MS/MS spectrum of the histone H3 27 to 40 peptide methylated on S28 and T32. MS, mass spectrometry.