Phosphoproteomics in Plants

Reversible modification of proteins by phosphorylation is crucial in regulating signal transduction in plants and other organisms. Research on protein phosphorylation has greatly benefitted from recent developments in mass spectrometry (MS)-based technology. In combination with this technology, different, highly specific phosphopeptide purification methods have been explored to determine hundreds to thousands of phosphorylation sites. Using accurate mass spectrometers, researchers are now able to quantitatively determine phosphopeptide concentrations from different samples on a large scale. Contrasting with studies on yeast and animal systems, phosphoproteomic research on plants has concentrated mainly on the identification of novel phosphorylation sites. Here, we describe recent MS-based approaches that will enable the elucidation of dynamic changes in plant phosphoproteomes induced by environmental signals.