title: Glycinebetaine enhances the tolerance of tomato plants to high temperature during germination of seeds and growth of seedlings.
abstract: Tomato (Lycopersicon esculentum cv. 'Moneymaker') was transformed with a codA gene, from Arthrobacter globiformis, for choline oxidase that had been modified to allow targeting to both chloroplasts and the cytosol. Glycinebetaine (GB) accumulated in seeds of transformed plants up to 1 µmol g(-1) dry weight (DW), while no detectable GB was found in wild-type (WT) seeds. The codA-transgenic seeds germinated faster and at higher frequency than WT seeds with high temperature treatment. After heat stress, levels of expression of a mitochondrial small heat-shock protein (MT-sHSP), heat-shock protein 70 (HSP70) and heat-shock cognate 70 (HSC70) were higher in transgenic seeds than in WT seeds during heat stress, and the accumulation of HSP70 was more prominent in codA-transgenic seeds than in WT seeds. Addition of GB to the germination medium or imbibition of seeds in a solution of GB enhanced the tolerance of WT seeds to high temperatures. WT seeds treated with exogenous GB also expressed heat-shock genes at elevated levels and accumulated more HSP70 than controls. Our results suggest that GB, either applied exogenously or accumulated in vivo in codA-transgenic seeds, enhanced the expression of heat-shock genes in and improved the tolerance to high temperature of tomato seeds during germination.
authors.affiliation: College of Life Science, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong, China.
authors.forename: Shufen
authors.initials: S
authors.lastname: Li
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Jianwei
authors.initials: J
authors.lastname: Wang
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.forename: Qingwei
authors.initials: Q
authors.lastname: Meng
authors.forename: Tony H H
authors.initials: TH
authors.lastname: Chen
authors.forename: Norio
authors.initials: N
authors.lastname: Murata
authors.forename: Xinghong
authors.initials: X
authors.lastname: Yang
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000429:Alcohol Oxidoreductases / Q000235:genetics / Q000378:metabolism; D001173:Arthrobacter / Q000201:enzymology; D001622:Betaine / Q000378:metabolism* / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006358:Hot Temperature; D018551:Solanum lycopersicum / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D014170:Transformation, Genetic / Q000187:drug effects; D019076:Transgenes / Q000235:genetics
chemical_list: D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; D001622:Betaine; D000429:Alcohol Oxidoreductases; C019888:choline oxidase