title: Phosphoproteomic analysis of the response of maize leaves to drought, heat and their combination stress.
abstract: Drought and heat stress, especially their combination, greatly affect crop production. Many studies have described transcriptome, proteome and phosphoproteome changes in response of plants to drought or heat stress. However, the study about the phosphoproteomic changes in response of crops to the combination stress is scare. To understand the mechanism of maize responses to the drought and heat combination stress, phosphoproteomic analysis was performed on maize leaves by using multiplex iTRAQ-based quantitative proteomic and LC-MS/MS methods. Five-leaf-stage maize was subjected to drought, heat or their combination, and the leaves were collected. Globally, heat, drought and the combined stress significantly changed the phosphorylation levels of 172, 149, and 144 phosphopeptides, respectively. These phosphopeptides corresponded to 282 proteins. Among them, 23 only responded to the combined stress and could not be predicted from their responses to single stressors; 30 and 75 only responded to drought and heat, respectively. Notably, 19 proteins were phosphorylated on different sites in response to the single and combination stresses. Of the seven significantly enriched phosphorylation motifs identified, two were common for all stresses, two were common for heat and the combined stress, and one was specific to the combined stress. The signaling pathways in which the phosphoproteins were involved clearly differed among the three stresses. Functional characterization of the phosphoproteins and the pathways identified here could lead to new targets for the enhancement of crop stress tolerance, which will be particularly important in the face of climate change and the increasing prevalence of abiotic stressors.
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Liuji
authors.initials: L
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Feiyun
authors.initials: F
authors.lastname: Zhao
authors.affiliation: Jiangsu Academy of Agricultural Sciences Institute of Biotechnology Nanjing, China.
authors.forename: Dayong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Nana
authors.initials: N
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University Guangzhou, China.
authors.forename: Guohui
authors.initials: G
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Chaohao
authors.initials: C
authors.lastname: Li
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Life Science, Henan Agricultural University Zhengzhou, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
keywords: drought and heat; iTRAQ labeling; maize; phosphoproteins; phosphoproteomics