Labeling of primary amines on peptides with reagents containing stable isotopes is a commonly used technique in quantitative mass spectrometry. Isobaric labeling techniques such as iTRAQ™ or TMT™ allow for relative quantification of peptides based on ratios of reporter ions in the low m/z region of spectra produced by precursor ion fragmentation. In contrast, nonisobaric labeling with mTRAQ™ yi...

Isobaric tags for absolute and relative quantitation (iTRAQ) allow for simultaneous relative quantification of peptides from up to eight different samples. Typically peptides labeled with 8-plex iTRAQ tags are pooled and fragmented using beam-type collision activated dissociation (CAD) which, in addition to cleaving the peptide backbone bonds, cleaves the tag to produce reporter ions. The relat...

A commercial reagent, known as the isobaric tag for relative and absolute quantification (iTRAQ), makes it possible to analyze multiple samples simultaneously. The ability of iTRAQ to compare relative protein abundances across as many as eight samples is a significant advantage over other stable isotope strategies, such as stable isotope labeling by amino acids in cell culture (SILAC) and isoto...

Both isobaric tags for relative and absolute quantitation (iTRAQ) and label-free methods are widely used for quantitative proteomics. Here, we provide a detailed evaluation of these proteomics approaches based on large datasets from biological samples. iTRAQ-label-based and label-free quantitations were compared using protein lysate samples from noninfected human lung epithelial A549 cells and ...

Cotton is an important economic crop, used mainly for the production of textile fiber. Using a space mutation breeding technique, a novel photosensitive genetic male sterile mutant CCRI9106 was isolated from the wild-type upland cotton cultivar CCRI040029. To study the male sterile mechanisms of CCRI9106, histological and iTRAQ-facilitated proteomic analyses of anthers were performed. This data...

In mass spectrometry(MS-) based quantitative proteomics research, the emerging iTRAQ (isobaric tag for relative and absolute quantitation) and TMT (tandem mass tags) techniques have been widely adopted for high throughput protein profiling. In a typical iTRAQ/TMT proteomics study, samples are grouped into batches and each batch is processed by one multiplex experiment, in which the abundances o...