title: A comprehensive differential proteomic study of nitrate deprivation in Arabidopsis reveals complex regulatory networks of plant nitrogen responses.
abstract: Nitrogen (N) is an important nutrient and signal for plant growth and development. However, to date, our knowledge of how plants sense and transduce the N signals is very limited. To better understand the molecular mechanisms of plant N responses, we took two-dimensional gel-based proteomic and phosphoproteomic approaches to profile the proteins with abundance and phosphorylation state changes during nitrate deprivation and recovery in the model plant Arabidopsis thaliana. After 7-day-old seedlings were N-deprived for up to 48 h followed by 24 h recovery, a total of 170 and 38 proteins were identified with significant changes in abundance and phosphorylation state, respectively. Bioinformatic analyses implicate these proteins in diverse cellular processes including N and protein metabolisms, photosynthesis, cytoskeleton, redox homeostasis, and signal transduction. Functional studies of the selected nitrate-responsive proteins indicate that the proteasome regulatory subunit RPT5a and the cytoskeleton protein Tubulin alpha-6 (TUA6) play important roles in plant nitrate responses by regulating plant N use efficiency (NUE) and low nitrate-induced anthocyanin biosynthesis, respectively. In conclusion, our study provides novel insights into plant responses to nitrate at the proteome level, which are expected to be highly useful for dissecting the N response pathways in higher plants and for improving plant NUE.
authors.affiliation: School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Bian
authors.forename: Kai
authors.initials: K
authors.lastname: Cheng
authors.forename: Hanfa
authors.initials: H
authors.lastname: Zou
authors.forename: Samuel Sai-Ming
authors.initials: SS
authors.lastname: Sun
authors.forename: Jun-Xian
authors.initials: JX
authors.lastname: He
mesh_terms: D017360:Arabidopsis / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000032:analysis / Q000378:metabolism*; D016000:Cluster Analysis; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D053263:Gene Regulatory Networks; D008954:Models, Biological; D009154:Mutation; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010641:Phenotype; D010750:Phosphoproteins / Q000032:analysis / Q000378:metabolism; D020543:Proteome / Q000032:analysis / Q000378:metabolism*; D040901:Proteomics / Q000379:methods; D015203:Reproducibility of Results; D013312:Stress, Physiological / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D009566:Nitrates; D010750:Phosphoproteins; D020543:Proteome; D009584:Nitrogen