title: The proteome and phosphoproteome of maize pollen uncovers fertility candidate proteins.
abstract: Maize is unique since it is both monoecious and diclinous (separate male and female flowers on the same plant). We investigated the proteome and phosphoproteome of maize pollen containing modified proteins and here we provide a comprehensive pollen proteome and phosphoproteome which contain 100,990 peptides from 6750 proteins and 5292 phosphorylated sites corresponding to 2257 maize phosphoproteins, respectively. Interestingly, among the total 27 overrepresented phosphosite motifs we identified here, 11 were novel motifs, which suggested different modification mechanisms in plants compared to those of animals. Enrichment analysis of pollen phosphoproteins showed that pathways including DNA synthesis/chromatin structure, regulation of RNA transcription, protein modification, cell organization, signal transduction, cell cycle, vesicle transport, transport of ions and metabolisms, which were involved in pollen development, the following germination and pollen tube growth, were regulated by phosphorylation. In this study, we also found 430 kinases and 105 phosphatases in the maize pollen phosphoproteome, among which calcium dependent protein kinases (CDPKs), leucine rich repeat kinase, SNF1 related protein kinases and MAPK family proteins were heavily enriched and further analyzed. From our research, we also uncovered hundreds of male sterility-associated proteins and phosphoproteins that might influence maize productivity and serve as targets for hybrid maize seed production. At last, a putative complex signaling pathway involving CDPKs, MAPKs, ubiquitin ligases and multiple fertility proteins was constructed. Overall, our data provides new insight for further investigation of protein phosphorylation status in mature maize pollen and construction of maize male sterile mutants in the future.
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Chao
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China.
authors.forename: Zhi-Fang
authors.initials: ZF
authors.lastname: Gao
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China.
authors.forename: Yue-Feng
authors.initials: YF
authors.lastname: Wang
authors.affiliation: The State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.affiliation: Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Xia-He
authors.initials: XH
authors.lastname: Huang
authors.affiliation: Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Wang
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China.
authors.forename: Ying-Chang
authors.initials: YC
authors.lastname: Mei
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China.
authors.forename: Biligen-Gaowa
authors.initials: BG
authors.lastname: Zhao
authors.affiliation: Institute of Crop Cultivation and Farming, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.affiliation: Institute of Crop Cultivation and Farming, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China.
authors.forename: Yu-Bo
authors.initials: YB
authors.lastname: Jiang
authors.affiliation: Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Beijing, 100093, China. wangbc@ibcas.ac.cn.
authors.forename: Bai-Chen
authors.initials: BC
authors.lastname: Wang
mesh_terms: D005298:Fertility / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics* / Q000502:physiology; D010766:Phosphorylation; D010940:Plant Proteins / Q000235:genetics* / Q000502:physiology; D011058:Pollen / Q000235:genetics*; D020543:Proteome / Q000235:genetics*; D003313:Zea mays / Q000235:genetics*
chemical_list: D010750:Phosphoproteins; D010940:Plant Proteins; D020543:Proteome
keywords: Kinase; Maize pollen; Male sterile; Motif; Phosphoproteome; Proteome