HEK293 cell were transfected with Flag-tagged SIRT6 and extracts were immunoprecipitated with anti-Flag.

The proteins extracted from the anti-Flag/Protein G agarose beads were run on an SDS-PAGE and the gel Coomassie stained (Figure 8 lane 2). The three major bands were excised and analysed by MALDI-TOF Mass Spectrometry. Mass spectra were collected and individual peptide ions were selected for fragmentation analysis by LIFT-MS/MS sequencing. Spectra were interpreted as described and the data searched against protein sequence databases using the Mascot programme. The table shows the detected ion, the corresponding peptide and the name of the protein in which that sequence is found and the Mascot E value reflecting confidence of the assignment. M = Methionine oxidised.