Quantitative Phosphoproteomic Analysis of Arabidopsis in Response to Salt and Hydrogen Peroxide Stresses

摘要

Salinity and oxidative stresses are major factors in affecting and limiting the productivity of agricultural crops.The study of biochemical and molecular responses of plants in response to those stresses is important for crop genetics and breeding.Extensive evidence shows that reversible protein phosphorylation plays a central role in mediating stress-regulated physiological responses,but little is known about its extent and function.Mass spectrometry provides a powerful tool for the in-depth analysis of systems biology.In this study,we performed a global quantitative analysis of the Arabidopsis phosphoproteomics in response to a time course of stress treatments using 15N-metabolic labeling and subcellular fractionation approaches.In total,we found 176 phosphoproteins showed to be regulated under stresses.Nine SnRK2 kinases identified to be differentially phosphorylated at multiple serine/threonine residues in their kinase domains following stress treatments,demonstrating different temporal phosphorylation induction of the various isoforms.K+ and Na+ transporters showed coordinated phosphorylation regulation under salt stress.In particular,nuclear proteins and protein kinases have high phosphorylation site occupancy in response to stress treatment.This suggests that the wide range of signaling and cellular processes that are modulated in this study.