title: Over-expression of an arabidopsis family A sucrose phosphate synthase (SPS) gene alters plant growth and fibre development.
abstract: The objective of this study was to manipulate the intracellular pools of sucrose by differentially expressing exogenous sucrose phosphate synthase (SPS) and investigating its role in regulating plant growth and fibre development. Tobacco (Nicotiana tabacum cv. Xanthi) plants were transformed with an arabidopsis SPS gene under the regulation of the ubiquitously expressed tandem repeat of the 35S cauliflower mosaic virus promoter, and subject to growth trials and fibre characterization. It was apparent that over-expression of SPS resulted in substantially elevated concentrations of sink sucrose pools compared to wild-type plants, while source tissue sucrose pools remained the same. All transformed plants had significantly increased stem height, which was ascribed to internode elongation, and greater stem diameters, longer fibers and increased total dry biomass relative to the control plants. Difference in the chemical composition of either the storage or structural carbohydrates of the wild-type and SPS transgenic lines were only minor. The correlation between increased stem sucrose content and plant phenotypes with elevated SPS gene expression confirm a role for sucrose availability in controlling plant growth and fibre elongation.
authors.affiliation: Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, Canada, V6T 1Z4.
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Park
authors.forename: Thomas
authors.initials: T
authors.lastname: Canam
authors.forename: Kyu-Young
authors.initials: KY
authors.lastname: Kang
authors.forename: David D
authors.initials: DD
authors.lastname: Ellis
authors.forename: Shawn D
authors.initials: SD
authors.lastname: Mansfield
mesh_terms: D029681:Arabidopsis Proteins / Q000235:genetics*; D018533:Biomass; D002473:Cell Wall / Q000737:chemistry; D018506:Gene Expression Regulation, Plant; D005964:Glucosyltransferases / Q000235:genetics*; D010641:Phenotype; D018547:Plant Stems / Q000166:cytology / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics*; D012313:RNA; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013395:Sucrose / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D012333:RNA, Messenger; D013395:Sucrose; D012313:RNA; D005964:Glucosyltransferases; C022698:sucrose-phosphate synthase