title: Identification of embryo proteins associated with seed germination and seedling establishment in germinating rice seeds.
abstract: Seed germination is a critical phase in the plant life cycle, but the mechanism of seed germination is still poorly understood. In the present study, rice (Oryza sativa L. cv. Peiai 64S) seeds were sampled individually when they reached different germination stages, quiescent, germinated sensu stricto, germinated completely and seedling, and were used to study the changes in the embryo proteome. A total of 88 protein spots showed a significant change in abundance during germination in water, and the results showed an activation of metabolic processes. Cell division, cell wall synthesis, and secondary metabolism were activated at late seed germination and during preparation for subsequent seedling establishment. Cycloheximide (CHX) at 70μM inhibited seedling establishment without an apparent negative effect on seed germination, while CHX at 500μM completely blocked seed germination. We used this observation to identify the potentially important proteins involved in seed germination (coleoptile protrusion) and seedling establishment (coleoptile and radicle protrusion). Twenty-six protein spots, mainly associated with sugar/polysaccharide metabolism and energy production, showed a significant difference in abundance during seed germination. Forty-nine protein spots, mainly involved in cell wall biosynthesis, proteolysis as well as cell defense and rescue, were required for seedling establishment. The results help improve our understanding of the key events (proteins) involved in germination and seedling development.
authors.affiliation: Key Laboratory of Plant Resources and Beijing Botanical Garden, 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 and Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Heng-Heng
authors.initials: HH
authors.lastname: Xu
authors.affiliation: Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Wei-Qing
authors.initials: WQ
authors.lastname: Wang
authors.affiliation: Hunan Hybrid Rice Research Center/State Key Laboratory of Hybrid Rice, Changsha 410125, China.
authors.forename: Ni
authors.initials: N
authors.lastname: Li
authors.affiliation: Hunan Hybrid Rice Research Center/State Key Laboratory of Hybrid Rice, Changsha 410125, China.
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Wang
authors.affiliation: Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Department of Molecular Biology and Genetics, Aarhus University, Flakkebjerg, Slagelse, DK-4200, Denmark.
authors.forename: Ian Max
authors.initials: IM
authors.lastname: Møller
authors.affiliation: Key Laboratory of Plant Resources and Beijing Botanical Garden, 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: D003513:Cycloheximide / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D018525:Germination / Q000187:drug effects*; D012275:Oryza / Q000235:genetics / Q000254:growth & development*; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D020543:Proteome; D036226:Seedlings / Q000235:genetics / Q000254:growth & development; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000254:growth & development
chemical_list: D010940:Plant Proteins; D011500:Protein Synthesis Inhibitors; D020543:Proteome; D003513:Cycloheximide
keywords: Embryo; Oryza sativa; Proteome analysis; Seed germination; Seedling establishment