Abstract
Phosphoenolpyruvate carboxylase (PEPC) plays a pivotal role in the photosynthetic CO2 fixation of C4 plants. However, the functions of PEPCs in C3 plants are less well characterized, particularly in relation to low atmospheric CO2 levels. Of the four genes encoding PEPC in Arabidopsis, PPC2 is considered as the major leaf PEPC gene. Here we show that the ppc2 mutants suffered a growth arrest when transferred to low atmospheric CO2 conditions, together with decreases in the maximum efficiency of PSII (Fv/Fm) and lower levels of leaf abscisic acid (ABA) and carbohydrates. The application of sucrose, malate, or ABA greatly rescued the growth of ppc2 lines under low CO2 conditions. Metabolite profiling analysis revealed that the levels of glycine and serine were increased in ppc2 leaves, while the abundance of photosynthetic metabolites was decreased under these conditions. The transcript levels of encoding enzymes involved in glycine or serine metabolism was decreased in ppc2 in an ABI5-dependent manner. Like the ppc2 mutants, abi5-1 mutants had lower photosynthetic rates and Fv/Fm compared with the wild type under photorespiratory conditions (i.e. low CO2 availability). However, the growth of these mutants was similar to that of the wild type under non-photorespiratory (low O2) conditions. The constitutive expression of ABI5 prevented the growth arrest of ppc2 lines under low CO2 conditions. These findings demonstrate that PPC2 plays an important role in the acclimation of Arabidopsis plants to low CO2 availability by linking photorespiratory metabolism to primary metabolism, and that this is mediated, at least in part, through ABA- and ABI5-dependent processes.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 11
Claim · model-written summary
ppc2 mutants arrested growth under low CO2.
- Taxon
- Arabidopsis
Arabidopsise1 - Material
- ppc2 mutantse0
- Outcome
- growth arreste0
- Setting
- low atmospheric CO2 conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ppc2 mutants suffered a growth arrest when transferred to low atmospheric CO2 conditions”
e1“in Arabidopsis”
Claim · model-written summary
ppc2 mutants had decreased Fv/Fm, ABA, and carbohydrates under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Outcome
- maximum efficiency of PSII (Fv/Fm) and lower levels of leaf abscisic acid (ABA) and carbohydratese0
- Direction
- decreasese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“decreases in the maximum efficiency of PSII (Fv/Fm) and lower levels of leaf abscisic acid (ABA) and carbohydrates”
e1“in Arabidopsis”
Claim · model-written summary
Sucrose rescued ppc2 growth under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Treatment
- sucrosee0
- Outcome
- growth of ppc2 linese0
- Direction
- rescuede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“application of sucrose, malate, or ABA greatly rescued the growth of ppc2 lines under low CO2 conditions”
e1“in Arabidopsis”
Claim · model-written summary
Malate rescued ppc2 growth under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Treatment
- malatee0
- Outcome
- growth of ppc2 linese0
- Direction
- rescuede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“application of sucrose, malate, or ABA greatly rescued the growth of ppc2 lines under low CO2 conditions”
e1“in Arabidopsis”
Claim · model-written summary
ABA rescued ppc2 growth under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Treatment
- ABAe0
- Outcome
- growth of ppc2 linese0
- Direction
- rescuede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“application of sucrose, malate, or ABA greatly rescued the growth of ppc2 lines under low CO2 conditions”
e1“in Arabidopsis”
Claim · model-written summary
Glycine and serine rose in ppc2 leaves.
- Taxon
- ArabidopsisArabidopsise1
- Outcome
- levels of glycine and serinee0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“levels of glycine and serine were increased in ppc2 leaves”
e1“in Arabidopsis”
Claim · model-written summary
Photosynthetic metabolite abundance decreased under these conditions.
- Taxon
- ArabidopsisArabidopsise1
- Outcome
- abundance of photosynthetic metabolitese0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“abundance of photosynthetic metabolites was decreased under these conditions”
e1“in Arabidopsis”
Claim · model-written summary
Transcripts for glycine or serine metabolism enzymes decreased in ppc2 in an ABI5-dependent manner.
- Taxon
- ArabidopsisArabidopsise1
- Gene
- ABI5e0
- Outcome
- transcript levels of encoding enzymes involved in glycine or serine metabolisme0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“transcript levels of encoding enzymes involved in glycine or serine metabolism was decreased in ppc2 in an ABI5-dependent manner”
e1“in Arabidopsis”
Claim · model-written summary
abi5-1 mutants had lower photosynthetic rates and Fv/Fm than wild type under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Material
- abi5-1 mutantse0
- Outcome
- photosynthetic rates and Fv/Fme0
- Direction
- lowere0
- Comparator
- wild typee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“abi5-1 mutants had lower photosynthetic rates and Fv/Fm compared with the wild type under photorespiratory conditions (i.e. low CO2 availability)”
e1“in Arabidopsis”
Claim · model-written summary
These mutants grew similarly to wild type under low O2.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“growth of these mutants was similar to that of the wild type under non-photorespiratory (low O2) conditions”
e1“in Arabidopsis”
Claim · model-written summary
Constitutive ABI5 expression prevented ppc2 growth arrest under low CO2.
- Taxon
- ArabidopsisArabidopsise1
- Treatment
- constitutive expression of ABI5e0
- Gene
- ABI5e0
- Outcome
- growth arrest of ppc2 linese0
- Direction
- preventede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“constitutive expression of ABI5 prevented the growth arrest of ppc2 lines under low CO2 conditions”
e1“in Arabidopsis”
The same questions in other papers
malate · growth · ArabidopsisPositive and negative results
1 in the opposite direction
- no effect
sucrose · growth · ArabidopsisPositive and negative results
8 papers in the same direction as this paper · 8 in the opposite direction
- negative
- negative
- negative
13 papers more in this group
See all 17 papers →(+)-abscisic acid · growth · ArabidopsisPositive and negative results
12 papers in the same direction as this paper · 13 in the opposite direction
- negative
- negative
- negative
22 papers more in this group
See all 26 papers →overexpression · growth · ArabidopsisPositive and negative results
70 papers in the same direction as this paper · 38 in the opposite direction
- negative
- negative
- negative
105 papers more in this group
See all 109 papers →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.