Proteome and Proteomics: From Single Protein To Whole Body - Proteome and Proteomics: From Single Protein To Whole Body - Open Access Pub

DOI10.14302/issn.2326-0793.jpgr-sp1-edt-1 Proteome is the entire set of proteins produced by a cellular system or an organism. Proteomics is the large-scale study of a proteome, which practically means an analysis of many proteins in parallel. Recently, it was proposed to separate Proteomics into Expression and Functional or Interaction (Cell Map) Proteomics which is the global analysis of protein expression and study of protein complexes and signaling pathways (virtually, protein interaction) accordingly 1. Protein analysis started after Laemmli created the technique for protein separation by electrophoresis in SDS-polyacrylamide gel 2. The next step, which allows the identification of the proteins, became Towbin’s Western blotting which is when proteins are transferred to the nitrocellulose (or PVDF) membrane following detection with a specific antibody 3. Another important method (Functional Proteomics) became the protein microarray for the identification of many proteins using the microchip, a solid support (glass slide, nitrocellulose membrane, beads, microtitre plate) to which an array of capture proteins is bound. The detection is usually performed with a specific probe which is labeled with a fluorescent dye following registration by a laser scanner 4. Expression Proteomics is based on 2-dimensional (2-D) gel electrophoresis and mass spectrometry. 2-D gel electrophoresis allows the separation of thousands of proteins by isoelectrofocusing followed by electrophoresis in gradient polyacrylamide gel 5. Another useful technique is Differential In-Gel Electrophoresis (DIGE) which is when proteins labeled with up to three different fluorescent dyes, run on the same 2-D gel and are individually scanned at appropriate fluorescent wavelengths 6. Mass spectrometry (MS) appeared with the great possibility of identifying and quantifying proteins in complex mixtures using a minimal amount of biological specimens 7. In fact, MS has a long history which started more than a century ago with the experiments of J.J.Thomson on ray particles. But the first analysis of amino acids and peptides using MS was performed by C.O. Anderson in 1958. The modern technique of MS is conditioned by the findings of A.J. Dempster, F.W.Aston, H.Dehmelt, W.Paul, J.B.Fenn, M.Karas, F. Hillenkamp, and K.Tanaka who developed the ion trap method, electrospray ionization, matrix-assisted laser desorption ionization and soft laser desorption. Mass spectrometry is a powerful and sensitive technique which is used to detect, identify and quantitate molecules by measuring the mass-to-charge