perspective on the use of iTRAQ[superscript TM] reagent technology for protein complex and profiling studies

• Published in: Journal of experimental botany 2006-04, Vol.57 (7), p.1501-1508
• Main Author: Zieske, Lynn R
• Format: Article
• Language: English
• Subjects: Amines; Animals; biochemical pathways; Biological and medical sciences; biomarkers; Biomarkers, Tumor; Cell biochemistry; Cell culture techniques; Cell physiology; Drug interactions; Endometrial Neoplasms - metabolism; Endometrium; Female; Fundamental and applied biological sciences. Psychology; gene expression; Gene Expression Profiling - methods; Indicators and Reagents; isobaric reagents; isotope labeling; Isotope Labeling - methods; Isotopic labeling; iTRAQ reagents; Mass spectroscopy; multi-protein complexes; Multiprotein Complexes - analysis; new methods; Phosphorylation; Plant physiology and development; plant proteins; plants; protein binding; protein complexes; protein composition; Protein Interaction Mapping - methods; protein synthesis; protein-protein interactions; Proteins; Proteomics; Proteomics - methods; quantitative analysis; Reagents; signal transduction
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/erj168

Proteomic research includes the characterization of protein mixtures in order to understand complex biological systems and determine relationships between proteins, their function, and protein-protein interactions. Often the goal of such research is to monitor changes of proteins in perturbed systems, a type of study referred to as differential expression analysis. To perform these studies requires the ability to execute some type of differential comparison of a given protein state in reference to some type of a control. The iTRAQ[superscript TM] reagents are a set of isobaric reagents which are amine specific and allow for the identification and quantitation of up to four different samples simultaneously. The amine specificity of these reagents makes most peptides in a sample amenable to this labeling strategy with no loss of information from samples involving post-translational modifications, such as the scrutiny of signal transduction pathways that often involve phosphorylation phenomena. In addition, the multiplexing capacity of these reagents allows for information replication within certain LC-MS/MS experimental regimes, providing additional statistical validation within any given experiment. The results presented herein demonstrate a few examples of the wide variety of quantitative information that can be realized when undertaking such experimental approaches. These include temporal analysis of drug-induced-protein expression, discovery and elucidation of disease markers, and protein-protein interactions in multi-protein complexes.