TABLE 2.
Summary of Acr-modified H4 peptides isolated from BEAS-2B cells exposed to Acr by LC-MS/MSa
| Peptide no. | Sequence | ΔMb (Da) | Protein name |
|---|---|---|---|
| 1 | 4GK(A)GGK(MP)GLGKGGAK(D)16 | +38, +76 | H4 |
| 2 | 0MSGRGK(A)GGK(MP)GLGK12 | +38, +76 | H4 |
| 3 | 9GLGK(FDP)GGAK(A)R17 | +94, +38 | H4 |
a
The ∼55-kDa gel band in the FDP-K IP lane in Fig. 2A was excised and digested with trypsin, and the resultant peptides were extracted and subjected to LC-MS/MS analysis. The aldimine (A)-, MP-, and FDP-modified peptides were identified. Peptides 1 to 3 show the identification of lysine modifications by Acr at the N terminus of H4, demonstrating that both H4K5 and H4K12, two lysine residues critical for histone nuclear import, are modified by Acr in vivo. D, dimethyl.
b
ΔM, mass difference.