title: Increase in the activity of fructose-1,6-bisphosphatase in cytosol affects sugar partitioning and increases the lateral shoots in tobacco plants at elevated CO2 levels.
abstract: We generated transgenic tobacco plants with high levels of fructose-1,6-bisphosphatase expressing cyanobacterialfructose-1,6-/sedoheptulose-1,7-bisphosphatase in the cytosol. At ambient CO(2) levels (360 ppm), growth, photosynthetic activity, and fresh weight were unchanged but the sucrose/hexose/starch ratio was slightly altered in the transgenic plants compared with wild-type plants. At elevated CO(2) levels (1200 ppm), lateral shoot, leaf number, and fresh weight were significantly increased in the transgenic plants. Photosynthetic activity was also increased. Hexose accumulated in the upper leaves in the wild-type plants, while sucrose and starch accumulated in the lower leaves and lateral shoots in the transgenic plants. These findings suggest that cytosolic fructose-1,6-bisphosphatase contributes to the efficient conversion of hexose into sucrose, and that the change in carbon partitioning affects photosynthetic capacity and morphogenesis at elevated CO(2) levels.
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara, 631-8505, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tamoi
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Hiramatsu
authors.forename: Shigeki
authors.initials: S
authors.lastname: Nedachi
authors.forename: Kumi
authors.initials: K
authors.lastname: Otori
authors.forename: Noriaki
authors.initials: N
authors.lastname: Tanabe
authors.forename: Takanori
authors.initials: T
authors.lastname: Maruta
authors.forename: Shigeru
authors.initials: S
authors.lastname: Shigeoka
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D002245:Carbon Dioxide / Q000378:metabolism*; D000458:Cyanobacteria / Q000201:enzymology / Q000235:genetics; D003600:Cytosol / Q000201:enzymology; D006597:Fructose-Bisphosphatase / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006601:Hexoses / Q000032:analysis / Q000378:metabolism; D018527:Hydroponics; D010641:Phenotype; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis; D018515:Plant Leaves / Q000254:growth & development; D018517:Plant Roots / Q000254:growth & development; D018520:Plant Shoots / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D013213:Starch / Q000032:analysis / Q000378:metabolism; D013395:Sucrose / Q000032:analysis / Q000378:metabolism; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D006601:Hexoses; D002245:Carbon Dioxide; D013395:Sucrose; D013213:Starch; D006597:Fructose-Bisphosphatase; D010744:Phosphoric Monoester Hydrolases; C022627:sedoheptulose-bisphosphatase