TY - JOUR
T1 - Analysis of histone modifications from tryptic peptides of deuteroacetylated isoforms
AU - Hersman, Elisabeth
AU - Nelson, Dwella M.
AU - Griffith, Wendell P.
AU - Jelinek, Christine
AU - Cotter, Robert J.
N1 - Funding Information:
This project was supported by grant U54 RR020839 from the National Institutes of Health , contract NHLBI N01HV28180 from the National Heart Lung and Blood Institute , and by NIH grant R01GM48646 to K.L.W. The LTQ-Orbitrap mass spectrometer used in this study was purchased through grant S10 RR023025 from the NIH High End Instrumentation Program to R.J.C. Analyses were carried out at the Middle Atlantic Mass Spectrometry Laboratory.
PY - 2012/2/15
Y1 - 2012/2/15
N2 - The in vitro deuteroacetylation of histones obtained from biological sources has been used previously in bottom-up mass spectrometry analyses to quantitate the percent of endogenous acetylation of specific lysine sites and/or peptides. In this report, derivatization of unmodified lysine residues on histones is used in combination with high performance mass spectrometry, including combined HPLC MS/MS, to distinguish and quantitate endogenously acetylated isoforms occurring within the same tryptic peptide sequence and to extend this derivatization strategy to other post-translational modifications, specifically methylation, dimethylation and trimethylation. The in vitro deuteroacetylation of monomethylated lysine residues is observed, though dimethylated or trimethylated residues are not derivatised. Comparison of the relative intensities ascribed to the deuteroacetylated and monomethylated species with the deuteroacetylated but unmethylated analog, provides an opportunity to estimate the percent of methylation at that site. In addition to the observed fragmentation patterns, the very high mass accuracy available on the Orbitrap mass spectrometer can be used to confirm the structural isoforms, and in particular to distinguish between trimethylated and acetylated species.
AB - The in vitro deuteroacetylation of histones obtained from biological sources has been used previously in bottom-up mass spectrometry analyses to quantitate the percent of endogenous acetylation of specific lysine sites and/or peptides. In this report, derivatization of unmodified lysine residues on histones is used in combination with high performance mass spectrometry, including combined HPLC MS/MS, to distinguish and quantitate endogenously acetylated isoforms occurring within the same tryptic peptide sequence and to extend this derivatization strategy to other post-translational modifications, specifically methylation, dimethylation and trimethylation. The in vitro deuteroacetylation of monomethylated lysine residues is observed, though dimethylated or trimethylated residues are not derivatised. Comparison of the relative intensities ascribed to the deuteroacetylated and monomethylated species with the deuteroacetylated but unmethylated analog, provides an opportunity to estimate the percent of methylation at that site. In addition to the observed fragmentation patterns, the very high mass accuracy available on the Orbitrap mass spectrometer can be used to confirm the structural isoforms, and in particular to distinguish between trimethylated and acetylated species.
KW - Acetylation
KW - Histones
KW - Methylation
KW - Orbitrap
KW - Proteomics
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U2 - 10.1016/j.ijms.2011.04.006
DO - 10.1016/j.ijms.2011.04.006
M3 - Article
C2 - 22389584
AN - SCOPUS:84857043850
VL - 312
SP - 5
EP - 16
JO - International Journal of Mass Spectrometry and Ion Processes
JF - International Journal of Mass Spectrometry and Ion Processes
SN - 1387-3806
ER -