528 / 2019-03-04 22:28:45

A new redox proteomics technology reveals role of a lipid transfer protein in plant stomatal defense

cysTMTRAQ, redox proteomics, lipid transfer protein, stomtal defense

全体主题 > Omics& New Technology

Redox-based post-translational modifications (PTMs) involving protein cysteine residues as redox sensors are important to various physiological processes. However, little is known about redox-sensitive proteins in guard cells and their functions in stomatal immunity. In this study, we developed a poweful integrative protein labeling technology cysTMTRAQ, which allows quantification of thiol-redox changes and protein level changes simultaneously. Using this new technology, we have identified guard cell proteins that were altered by thiol PTMs in response to a bacterial flagellin peptide flg22. In total, eight, seven and 20 potential redox-responsive proteins were identified in guard cells treated with flg22 for 15, 30 and 60 min, respectively. The proteins fall into several functional groups including photosynthesis, lipid binding, oxidation-reduction process, and defense. Among the proteins, a lipid transfer protein LTP-II was confirmed to be redox responsive and involved in plant resistance to Pseudomonas syringe pv. tomato DC3000. This study not only creates an inventory of potential redox proteins in flg22 signal transduction in guard cells and highlights the relevance of the lipid transfer protein in plant defense against the bacterial pathogen, but also shows the utility of cysTMTRAQ in broad application to studying protein thiol-redox changes in many areas of biological research.