Carbon metabolism in leaves of transgenic tobacco (Nicotiana tabacum L.) containing elevated fructose 2,6-bisphosphate levels.

Journal article

The aim of this work was to investigate the role of fructose 2,6-bisphosphate (Fru 2,6-P2) during photosynthesis. The level of Fru 2,6-P2 in tobacco plants was elevated by the introduction of a modified mammalian gene encoding 6-phosphofructo-2-kinase (6-PF-2-K). Estimates of the metabolite control coefficient (C) for Fru 2,6-P2 levels in response to increased 6-PF-2-K activity, suggest that small increases in 6-PF-2-K activity have little effect upon steady-state Fru 2,6-P2 levels (C = +0.08 for a 0-58% increase in 6-PF-2-K activity). However, larger changes resulted in dramatic rises in Fru 2,6-P2 levels (C = +3.35 for 206-268% increase in 6-PF-2-K activity). Transgenic plants contained Fru 2,6-P2 levels in the dark that ranged from 104 to 230% of the level in wild-type tobacco. Plants with altered levels of Fru 2,6-P2 were used to determine the effects of this signal metabolite upon carbohydrate metabolism during the initial phase of the light period. Here we provide direct evidence that Fru 2,6-P2 contributes to the regulation of carbon partitioning in tobacco leaves by inhibiting sucrose synthesis.

Authors: Scott, P; Lange, A; Pilkis, S; Kruger, N

• Publication status: Published
• Journal: Plant journal : for cell and molecular biology
• Volume: 7
• Issue: 3
• Pages: 461-469
• Publication date: 1995-03-01
• DOI: 10.1046/j.1365-313x.1995.7030461.x
• EISSN: 1365-313X
• ISSN: 0960-7412
• Language: English
• Keywords: Phosphotransferases (Alcohol Group Acceptor); Plants, Genetically Modified; Animals; Molecular Sequence Data; Liver; Plants, Toxic; DNA Primers; Carbohydrate Metabolism; Rats; Carbon; Tobacco; Base Sequence; Genes, Plant; Fructosediphosphates; Phosphofructokinase-2