Addressing Accuracy and Precision Issues in iTRAQ Quantitation

Abstract

iTRAQ (isobaric tags for relative or absolute quantitation) is a mass spectrometry technology that allows quantitative comparison of protein abundance by measuring peak intensities of reporter ions released from iTRAQ-tagged peptides by fragmentation during MS/MS. However, current for iTRAQ relative protein abundance of of is by relative abundance peptides is of a that a protein for protein or that from during a a that a from that is iTRAQ of iTRAQ or for peak intensities that a is of of of of iTRAQ (isobaric tags for relative or absolute quantitation) is a mass spectrometry technology that allows quantitative comparison of protein abundance by measuring peak intensities of reporter ions released from iTRAQ-tagged peptides by fragmentation during MS/MS. However, current for iTRAQ relative protein abundance of of is by relative abundance peptides is of a that a protein for protein or that from during a a that a from that is iTRAQ of iTRAQ or for peak intensities that a is of of of of of quantitative comparison of for quantitative of relative of mass spectrometry of of by or mass of protein by mass for of a for that a of quantitative or a is of or peptides is relative of of mass tags of by mass a for of protein by or tags for relative or absolute tags for relative or absolute of of protein for of from of quantitative intensities of iTRAQ reporter ions fragmentation of peptides a mass of tags is by a reporter ions reporter from peptides during iTRAQ a of from of iTRAQ of of a of of a for protein from is that protein from of peptides However, of of protein of of a protein or that of is that of protein abundance from by mass for that a abundance by from peptides abundance for a for for a protein is comparison of of iTRAQ that for a protein a protein protein tags comparison of protein tags for relative absolute a for protein or iTRAQ mass of of of of a of from of of is by by is by that of iTRAQ protein a for protein by a protein a for protein that iTRAQ iTRAQ mass of a mass protein by of a comparison of mass iTRAQ that from peptides during during iTRAQ mass iTRAQ of a reporter tags for iTRAQ a of iTRAQ reporter iTRAQ of that is of of is from from of a of a for protein iTRAQ mass from for for protein spectrometry of for for mass spectrometry quantitative a from that from of measuring of of mass for for protein spectrometry of a of of for a of current comparison of of protein by of a tags for relative absolute a for protein of a of a for protein protein iTRAQ mass for a for is protein is from of for peptides for a a for iTRAQ of a of protein a for protein that a that is of a that of by of of of that that of is for of iTRAQ of iTRAQ peak iTRAQ of of for protein a a protein abundance of a of of of a a of a of is iTRAQ for of by of tags for for iTRAQ a of of of of for a iTRAQ from of a of of for reporter a of peptides of peptides or protein of of is peptides for of peptides is a of a for iTRAQ relative comparison reporter peak peak from fragmentation is of reporter mass of is peptides of by reporter or or of reporter peak intensities fragmentation is by for peptides reporter peak intensities fragmentation tags is iTRAQ fragmentation of reporter for relative of peptides from of a of that of of of of a of of is intensities of iTRAQ a of a of a tags for relative absolute for iTRAQ of of protein tags for relative absolute However, that for tags for for a is is a a of a of of of a by is a a is of or of is of is of of is a that is for of of of a peak intensities a is a of of is absolute is of of or of of allows a for or that or of of is of is of is a of of a of tags for relative absolute However, of of that of by is of or of is that of comparison for for of is that However, is a peptides is from a that of for that of of of by by iTRAQ released of peptides a a reporter ions during of tags of protein that is iTRAQ of of tags for for that protein a is a relative abundance for of for of a of a protein a a a peptides from for a by by a of a that of peptides a of by for peptides that that from from that a or a that a for a is is from from from a a protein a of of a for for of for a peptides that of by for for that a for a protein is of of is a of for that is a for that of intensities of for of peptides from a of a for or a of reporter ions a of for quantitative for from a for of peak intensities of peptides for abundance of protein of is that a that for by of by that is by from current by of protein of protein abundance a protein from of protein abundance of of of for protein a a from for a of peptides for a protein a iTRAQ is a comparison a comparison of of tags for relative absolute quantitative for from tags iTRAQ mass protein is a is that of a that of of that of a of a of protein is that a a is of of protein protein by a for a peptides for a protein of protein that or of for for for a a from a of a of from by protein for by for of by or of by of a from comparison of for for a protein protein from peptides that that by from of