Open AccessEnrichment of Phosphoproteins and Phosphopeptide Derivatization Identify Universal Stress Proteins in Elicitor-Treated Arabidopsis
Author(s) -
Marit Lenman,
Carolin Sörensson,
Erik Andréasson
Publication year - 2008
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-21-10-1275
Subject(s) - phosphopeptide , phosphorylation , arabidopsis , chemistry , biochemistry , protein phosphorylation , population , derivatization , proteomics , mass spectrometry , chromatography , biology , mutant , protein kinase a , demography , sociology , gene
Protein phosphorylation is a key biological process that regulates reactions involved in plant-microbe interactions. The phosphorylated form of a protein often represents only a small fraction of the total population and can be problematic to analyze in a mass spectrometer. We demonstrate how a titanium dioxide (TiO(2)) resin can be employed for the enrichment of phosphoproteins, as well as a method to derivatize TiO(2)-purified phosphopeptides to facilitate determination of the exact site of phosphorylation. The use of these methods was exemplified by the identification of two plant proteins that were shown to be phosphorylated after the elicitation of Arabidopsis cells with Phytophthora infestans zoospores and xylanase. Both of the proteins that were identified, At5g54430.1 and At4g27320.1, were found to contain a universal stress protein domain with conserved residues for ATP binding.