Combined pulsed-Q dissociation and electron transfer dissociation for identification and quantification of iTRAQ-labeled phosphopeptides.
Here, we report a new approach that integrates pulsed Q dissociation (PQD) and electron transfer dissociation (ETD) techniques for confident and quantitative identification of iTRAQ-labeled phosphopeptides. The use of isobaric tags for relative and absolute quantification enables a high-throughput quantification of peptides via reporter ion signals in the low m/z range of tandem mass spectra. PQD, a form of ion trap collision activated dissociation, allows for detection of low mass-to-charge fragment ions, and electron transfer dissociation is especially useful for sequencing peptides that contain post-translational modifications. Analysis of the phosphoproteome of human fibroblast cells using a sensitive linear ion trap mass spectrometer demonstrated that this hybrid approach improves both identification and quantification of phosphopeptides. ETD improved phosphopeptide identification, while PQD provides improved quantification of iTRAQ-labeled phosphopeptides.
Yang
Feng
F
Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Wu
Si
S
Stenoien
David L
DL
Zhao
Rui
R
Monroe
Matthew E
ME
Gritsenko
Marina A
MA
Purvine
Samuel O
SO
Polpitiya
Ashoka D
AD
Tolić
Nikola
N
Zhang
Qibin
Q
Norbeck
Angela D
AD
Orton
Daniel J
DJ
Moore
Ronald J
RJ
Tang
Keqi
K
Anderson
Gordon A
GA
Pasa-Tolić
Ljiljana
L
Camp
David G
DG
Smith
Richard D
RD
D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004579:Electron Transport; D007202:Indicators and Reagents; D010748:Phosphopeptides / Q000032:analysis*; D011499:Protein Processing, Post-Translational; D053719:Tandem Mass Spectrometry / Q000379:methods*
D007202:Indicators and Reagents; D010748:Phosphopeptides