Plant Proteomics

The proteome is defined as the set of all expressed proteins in a cell, tissue or organism. At present, two techniques are absolutely central for proteomic analyses: (1) two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), which can separate thousands of proteins, and (2) mass spectrometry (MS) for the identification of proteins and their post-translational modifications. Proteomic analysis of protein mixtures can be subdivided into four essential steps involving sample preparation (step 1), protein separation in combination with differential analysis of the resulting protein patterns (step 2), proteolytic digestion of the target proteins (step 3), followed by protein identification via peptide mass fingerprinting (PMF((step 4), followed by database searching of the resulting peptide masses. Since proteins serve as important components of major signaling and biochemical pathways, studies at protein levels are essential to reveal molecular mechanisms underlying plant growth, development, and interactions with the environment. Proteomic analyses of plant organs or tissues were applied to monitor developmental changes or the influence of environmental stimuli on protein patterns. In this review, proteomics technique and its applications on plant researches will be outlined.