The fission yeast mitotic activator cdc25 and sucrose induce early flowering synergistically in the day-neutral Nicotiana tabacum cv. Samsun.
Here, the tobacco (Nicotiana tabacum) day-neutral (DN) cv. Samsun transformed with the Schizosaccharomyces pombe mitotic activator gene Spcdc25 was used to study the onset of flowering. Wild type (WT) and cdc25 plants were grown from seeds in vitro until they were 20 cm high. Apical and basal nodes were then subcultured repeatedly and the regenerated plants were used to document time to flowering and the number of leaves formed before flowering. Three sucrose treatments (3, 5 or 7% (weight/volume)) were used and measurements of leaf endogenous soluble carbohydrates were performed. In the 3% treatment, cdc25 plants flowered but WT plants did not. The higher sucrose treatments enabled WT flowering; two-thirds of the plants flowered at 5%, while all plants flowered at 7% sucrose. However, in all treatments, cdc25 plants exhibited significantly earlier flowering and fewer leaves compared with wild type. Remarkably, a typical acropetal flowering gradient in WT plants did not occur in cdc25 plants. In cdc25 leaves, there were significantly higher amounts of endogenous sugars with a higher proportion of sucrose compared with WT. Our data demonstrate that Spcdc25 expression and sucrose act synergistically to induce precocious flowering.
Teichmanová
Martina
M
Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic.
Mašková
Petra
P
Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic.
Vojvodová
Petra
P
Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic.
Krekule
Jan
J
Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Karlovce 1, 160 00, Prague 6, Czech Republic.
Francis
Dennis
D
School of Biosciences, Cardiff University, PO Box 915, Cardiff CF10 3TL, UK.
Lipavská
Helena
H
Department of Plant Physiology, Faculty of Science, Charles University, Viničná 5, 128 44, Prague 2, Czech Republic.
D050260:Carbohydrate Metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000187:drug effects* / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D018517:Plant Roots / Q000254:growth & development; D030821:Plants, Genetically Modified; D012568:Schizosaccharomyces / Q000235:genetics; D013395:Sucrose / Q000494:pharmacology*; D013997:Time Factors; D014026:Nicotiana / Q000187:drug effects* / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D020666:ras-GRF1 / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D020666:ras-GRF1; D013395:Sucrose