title: The role of nitrogen in leaf senescence of summer maize and analysis of underlying mechanisms using comparative proteomics.
abstract: Leaf senescence is associated with fundamental changes on the level of the proteome and it can be modulated by nitrogen. To determine the precise regulatory mechanisms underlying these effects, we conducted a comparative proteomics study using 2-dimensional gel electrophoresis and MALDI-TOF/TOF MS. Based on our study of the maize leaf proteome, leaf senescence induces complex responses including the degradation of 32 senescence-associated proteins that are involved in many biological processes, especially energy, metabolism and cell rescue, defense and virulence pathways. Although similar conclusions have been highlighted in other crops, this study filled the knowledge gap in maize leaf senescence. Moreover, we discovered, for the first time, 29 "nitrogen-regulated senescence proteins" had significant (P≤0.05) interaction term for nitrogen×stage. Although further study of nitrogen-related senescence proteins, such as 30S ribosomal protein, will be required to fully elucidate their complex functions, the surprising results in our study provide a new vision to research the relationship between nitrogen and senescence.
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Jiwang
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China.
authors.forename: Geng
authors.initials: G
authors.lastname: Li
authors.affiliation: State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai-an, Shandong 271018, PR China. Electronic address: stdong@sdau.edu.cn.
authors.forename: Shuting
authors.initials: S
authors.lastname: Dong
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D013058:Mass Spectrometry; D009584:Nitrogen / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020543:Proteome; D040901:Proteomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D020543:Proteome; D009584:Nitrogen
keywords: Comparative proteomics; Maize leaf; Nitrogen; Senescence