title: Proteome analysis reveals an energy-dependent central process for Populus×canadensis seed germination.
abstract: Poplar (Populus×canadensis) seeds rapidly germinated in darkness at 10, 15, and 20°C and reached 50% seed germination after about 22, 4.5, and 3.5h, respectively. Germination of poplar seeds was markedly inhibited by abscisic acid (ABA) at 50μM and cycloheximide (CHX) at 100μM, and these inhibitive roles were temperature-dependent. In the present study, mature poplar seeds were used to investigate the differentially changed proteome of seeds germinating in water, ABA, and CHX. A total of 130 protein spots showed a significant change (1.5-fold increase/decrease, P<0.05) in abundance, and 101 protein spots were successfully identified. Most of the proteins were associated with cell defense and rescue (21%), storage proteins (21%), protein synthesis and destination (20%), metabolism (16%), and energy (14%). The germination of poplar seeds is closely related with the increase in those proteins involved in amino acid and lipid metabolism, the tricarboxylic acid cycle and pentose phosphate pathway, protein synthesis and destination, cell defense and rescue, and degradation of storage proteins. ABA and CHX inhibit the germination of poplar seeds by decreasing the protein abundance associated with protein proteolysis, protein folding, and storage proteins. We conclude that poplar seed germination is an energy-dependent active process, and is accompanied by increasing amino acid activation, protein synthesis and destination, as well as cell defense and rescue, and degradation of storage proteins.
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China.
authors.forename: Ke-Xin
authors.initials: KX
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Wei-Qing
authors.initials: WQ
authors.lastname: Wang
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Shu-Jun
authors.initials: SJ
authors.lastname: Liu
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China. Electronic address: sqsong@ibcas.ac.cn.
authors.forename: Song-Quan
authors.initials: SQ
authors.lastname: Song
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D003513:Cycloheximide / Q000378:metabolism; D018525:Germination / Q000502:physiology*; D010940:Plant Proteins / Q000378:metabolism; D032107:Populus / Q000378:metabolism* / Q000502:physiology*; D020543:Proteome / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism / Q000502:physiology
chemical_list: D010940:Plant Proteins; D020543:Proteome; D000040:Abscisic Acid; D003513:Cycloheximide
keywords: ABA; Cycloheximide; Germination; Poplar seed; Proteome