Fig. 3.

Mapping the H3K36 sensing site using photo-cross-linking MS. (A) In the experimental workflow, a diazirine-containing probe peptide is incubated with PRC2 and the mixture is UV-irradiated. Following enrichment and digestion, MS is used to map the H3K36 sensing site. Details of probe synthesis are provided in SI Appendix, Fig. S9. (B) Representative MS/MS spectrum corresponding to a cross-link between the probe peptide and the EZH2 subunit. (SI Appendix, Table S1 identifies all cross-links.)