Abstract
Cytosolic GS1 (Gln synthetase) is central for ammonium assimilation in plants. High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis (Arabidopsis thaliana) shoots. Under the same conditions, the expression of the high-affinity low-capacity isoform Gln-1;1 was reduced. The expression of Gln-1;3 did not respond to ammonium treatment while Gln-1;4 and Gln-1;5 isogenes in all cases were expressed at a very low level. Gln-2 was highly expressed in shoots but only at a very low level in roots. To investigate the specific functions of the two isogenes Gln-1;1 and Gln-1;2 in shoots for ammonium detoxification, single and double knock-out mutants were grown under standard N supply or with high ammonium provision. Phenotypes of the single mutant gln1;1 were similar to the wild type, while growth of the gln1;2 single mutant and the gln1;1:gln1;2 double mutant was significantly impaired irrespective of N regime. GS1 activity was significantly reduced in both gln1;2 and gln1;1:gln1;2 Along with this, the ammonium content increased while that of Gln decreased, showing that Gln-1;2 was essential for ammonium assimilation and amino acid synthesis. We conclude that Gln-1;2 is the main isozyme contributing to shoot GS1 activity in vegetative growth stages and can be up-regulated to relieve ammonium toxicity. This reveals, to our knowledge, a novel shoot function of Gln-1;2 in Arabidopsis shoots.
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
High ammonium enhanced Gln-1;2 expression in Arabidopsis shoots.
- Taxon
- Arabidopsis
Arabidopsise0 - Treatment
- High ammonium treatmente0
- Gene
- Gln-1;2e0
- Outcome
- expression of the GS1 isogene Gln-1;2e0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis (Arabidopsis thaliana) shoots.”
Claim · model-written summary
High ammonium reduced Gln-1;1 expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- same conditionse0
- Gene
- Gln-1;1e0
- Outcome
- expression of the high-affinity low-capacity isoform Gln-1;1e0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under the same conditions, the expression of the high-affinity low-capacity isoform Gln-1;1 was reduced.”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
Gln-1;3 expression did not respond to ammonium treatment.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- ammonium treatmente0
- Gene
- Gln-1;3e0
- Outcome
- expression of Gln-1;3e0
- Direction
- did not responde0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The expression of Gln-1;3 did not respond to ammonium treatment”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
Gln-1;4 and Gln-1;5 expression remained very low.
- Taxon
- ArabidopsisArabidopsist0
- Gene
- Gln-1;4 and Gln-1;5e0
- Outcome
- expressed at a very low levele0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Gln-1;4 and Gln-1;5 isogenes in all cases were expressed at a very low level.”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
Gln-2 expression was high in shoots and very low in roots.
- Taxon
- ArabidopsisArabidopsist0
- Gene
- Gln-2e0
- Outcome
- highly expressed in shoots but only at a very low level in rootse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Gln-2 was highly expressed in shoots but only at a very low level in roots.”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
The gln1;1 mutant resembled wild type.
- Taxon
- ArabidopsisArabidopsist0
- Material
- gln1;1e0
- Outcome
- Phenotypese0
- Comparator
- wild typee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Phenotypes of the single mutant gln1;1 were similar to the wild type”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
The gln1;2 mutant had significantly impaired growth irrespective of nitrogen regime.
- Taxon
- ArabidopsisArabidopsist0
- Material
- gln1;2 single mutante0
- Outcome
- growthe0
- Direction
- impairede0
- Qualifier
- irrespective of N regimee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“growth of the gln1;2 single mutant and the gln1;1:gln1;2 double mutant was significantly impaired irrespective of N regime.”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
The gln1;1:gln1;2 double mutant had significantly impaired growth irrespective of nitrogen regime.
- Taxon
- ArabidopsisArabidopsist0
- Material
- gln1;1:gln1;2 double mutante0
- Outcome
- growthe0
- Direction
- impairede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“growth of the gln1;2 single mutant and the gln1;1:gln1;2 double mutant was significantly impaired irrespective of N regime.”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
GS1 activity was significantly reduced in both gln1;2 mutant types.
- Taxon
- ArabidopsisArabidopsist0
- Material
- gln1;2 and gln1;1:gln1;2e0
- Gene
- GS1e0
- Outcome
- GS1 activitye0
- Direction
- reducede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“GS1 activity was significantly reduced in both gln1;2 and gln1;1:gln1;2”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
Ammonium content increased in the mutants.
- Taxon
- ArabidopsisArabidopsist0
- Outcome
- ammonium contente0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the ammonium content increased while that of Gln decreased”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
Claim · model-written summary
Gln content decreased in the mutants.
- Taxon
- ArabidopsisArabidopsist0
- Outcome
- that of Glne0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the ammonium content increased while that of Gln decreased”
t0“High ammonium treatment enhanced the expression of the GS1 isogene Gln-1;2 encoding a low-affinity high-capacity GS1 protein in Arabidopsis”
The same questions in other papers
nitrogen · molecular: expression · ArabidopsisPositive and negative results
5 papers in the same direction as this paper · 12 in the opposite direction
- no effect
- negative
- no effect
14 papers more in this group
See all 18 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.