Submitted to: In Vitro Diagnostic Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/11/2002
Publication Date: 9/20/2002
Citation: TABATABAI, L.B. USING PROTEOMICS IN DIAGNOSTICS. IN VITRO DIAGNOSTIC TECHNOLOGY. 2002. v. 8(7). p.37-48.
Interpretive Summary: Proteomics (protein and genomics) is a relatively new technology that employs two-dimensional electrophoresis (2-DE) for protein sample (proteome) separation, followed by mass spectrometry of the in-gel trypsin-digested protein fragments for protein identification. Alternative methods introduced to circumvent the initial drawbacks of the 2-DE method include the following technologies: (a) differential protein fractionation and chromatography, prior to mass spectrometry; (b) labeling cysteinyl residues of proteins with a stable isotope-coded affinity label, followed by trypsin digestion, affinity purification, and mass spectrometry; (c) biomolecular interaction isolation of proteins, followed by mass spectrometry, including protein microarray technology. Advantages, limitations, and applications were discussed.
Technical Abstract: Proteomics or analysis of the proteome (protein and genome coined by Wilkins et al.) offers a relatively new approach to protein expression profiling and cellular or tissue protein identification from samples obtained under various specified conditions. Proteome analysis allows the investigator to obtain information on protein identity, protein/protein interaction, level of protein expression and protein expression profiling, protein trafficking and turnover, protein variants, and protein post-translational modifications. This relatively new approach combines two-dimensional electrophoresis (2-DE), a high-resolution protein separation technique, with mass spectrometry, either matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF) or electrospray ionization (ESI) mass spectrometry or hybrid instrumentation. The 2-DE technique, however, has inherent limitations. Developments in 2-DE procedures and new techniques in sample preparation have overcome most of the obstacles due to low protein abundance, dynamic range of proteins to be separated, and solubilization of integral membrane proteins. Because of the need to fully automate the entire proteome analysis process, new approaches have been explored to proteome analysis. Nevertheless, the 2-DE technique seems to remain one of the highest-resolution methodologies that can provide a "snapshot" of the cell's protein expression status. For clinical and other biological research applications, the 2-DE technique will remain most likely the premier protein separation technique until new methodologies are introduced for direct protein expression profiling and identification.