Abstract
A ferredoxin-NADP+ oxidoreductase (FNR) cDNA from tobacco (Nicotiana tabacum cv. Samsun) was cloned and sequenced. Comparison of the deduced amino acid sequence revealed high identity to FNR proteins from Capsicum annuum, Pisum sativum, Spinacia oleracea and Vicia faba. Transgenic tobacco plants were generated that constitutively express the FNR cDNA in reverse orientation between the CaMV 35S promoter and the polyadenylation signal of the octopine synthase gene. Plants expressing the FNR antisense gene showed lower levels of FNR mRNA and protein accumulation, which was paralleled by a decrease in FNR activity. As a consequence, NADPH levels declined whereas NADP+ levels increased, leading to an unaltered NADP(H) pool. Growth rates, chlorophyll content and net CO2 uptake rates at high and low irradiances were strongly reduced in FNR antisense tobacco plants. These changes were accompanied by an over-reduced state of P700 as estimated by absorption changes at 820 nm. FNR control coefficients determined for the photosynthetic rate at saturating (C(R) = 0.94) and limiting (C(R) = 0.70) light conditions revealed a prominent role of this reductase in the regulation of photosynthesis.
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Claims 11
Claim · model-written summary
Tobacco FNR cDNA was cloned and sequenced.
- Taxon
- tobacco
Nicotiana tabacume0 - Material
- Nicotiana tabacum cv. Samsune0
- Gene
- ferredoxin-NADP+ oxidoreductase (FNR)e0
- Outcome
- cloned and sequencede0
Not reportedComparatorValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A ferredoxin-NADP+ oxidoreductase (FNR) cDNA from tobacco (Nicotiana tabacum cv. Samsun) was cloned and sequenced.”
Claim · model-written summary
The deduced tobacco FNR amino acid sequence had high identity to proteins from four other plants.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Gene
- FNRe0
- Outcome
- high identity to FNR proteinse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Comparison of the deduced amino acid sequence revealed high identity to FNR proteins from Capsicum annuum, Pisum sativum, Spinacia oleracea and Vicia faba.”
t0“tobacco plants”
Claim · model-written summary
FNR antisense plants had lower FNR mRNA and protein accumulation.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Treatment
- FNR antisense genee0
- Gene
- FNRe0
- Outcome
- FNR mRNA and protein accumulatione0
- Direction
- lowere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants expressing the FNR antisense gene showed lower levels of FNR mRNA and protein accumulation”
t0“tobacco plants”
Claim · model-written summary
FNR activity decreased in antisense plants.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Treatment
- FNR antisensee1
- Gene
- FNRe0
- Outcome
- FNR activitye0
- Direction
- decreasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“which was paralleled by a decrease in FNR activity.”
t0“transgenic tobacco plants”
e1“FNR antisense tobacco plants”
Claim · model-written summary
NADPH levels declined in FNR antisense plants.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Treatment
- FNR antisensee1
- Outcome
- NADPH levelse0
- Direction
- declinede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“NADPH levels declined whereas NADP+ levels increased”
t0“transgenic tobacco plants”
e1“FNR antisense tobacco plants”
Claim · model-written summary
NADP+ levels increased in FNR antisense plants.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Treatment
- FNR antisensee1
- Outcome
- NADP+ levelse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“NADPH levels declined whereas NADP+ levels increased”
t0“transgenic tobacco plants”
e1“FNR antisense tobacco plants”
Claim · model-written summary
The NADP(H) pool remained unaltered.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Treatment
- FNR antisensee1
- Outcome
- NADP(H) poole0
- Direction
- unalterede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“leading to an unaltered NADP(H) pool.”
t0“transgenic tobacco plants”
e1“FNR antisense tobacco plants”
Claim · model-written summary
Growth rates, chlorophyll content and net CO2 uptake rates were strongly reduced in FNR antisense tobacco plants.
- Taxon
- tobacco plantsNicotiana tabacume0
- Treatment
- FNR antisensee0
- Outcome
- Growth rates, chlorophyll content and net CO2 uptake ratese0
- Direction
- strongly reducede0
- Qualifier
- high and low irradiancese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Growth rates, chlorophyll content and net CO2 uptake rates at high and low irradiances were strongly reduced in FNR antisense tobacco plants.”
Claim · model-written summary
P700 was over-reduced in FNR antisense plants.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Gene
- P700e0
- Outcome
- over-reduced state of P700e0
- Direction
- over-reducede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“These changes were accompanied by an over-reduced state of P700 as estimated by absorption changes at 820 nm.”
t0“transgenic tobacco plants”
Claim · model-written summary
FNR had a photosynthetic control coefficient of 0.94 at saturating light.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Gene
- FNRe0
- Outcome
- control coefficients determined for the photosynthetic ratee0
- Value
- C(R) = 0.94e0
- Qualifier
- saturatinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“FNR control coefficients determined for the photosynthetic rate at saturating (C(R) = 0.94) and limiting (C(R) = 0.70) light conditions”
t0“tobacco plants”
Claim · model-written summary
FNR had a photosynthetic control coefficient of 0.70 at limiting light.
- Taxon
- tobacco plantsNicotiana tabacumt0
- Gene
- FNRe0
- Outcome
- control coefficients determined for the photosynthetic ratee0
- Value
- C(R) = 0.70e0
- Qualifier
- limitinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“FNR control coefficients determined for the photosynthetic rate at saturating (C(R) = 0.94) and limiting (C(R) = 0.70) light conditions”
t0“tobacco plants”
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Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.