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.
Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Feng
F
Yang
Si
S
Wu
David L
DL
Stenoien
Rui
R
Zhao
Matthew E
ME
Monroe
Marina A
MA
Gritsenko
Samuel O
SO
Purvine
Ashoka D
AD
Polpitiya
Nikola
N
Tolić
Qibin
Q
Zhang
Angela D
AD
Norbeck
Daniel J
DJ
Orton
Ronald J
RJ
Moore
Keqi
K
Tang
Gordon A
GA
Anderson
Ljiljana
L
Pasa-Tolić
David G
DG
Camp
Richard D
RD
Smith
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