Abstract
Pentavalent methylated arsenic (As) species such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)] are used as herbicides or pesticides, and can also be synthesized by soil microorganisms or algae through As methylation. The mechanism of MMA(V) and DMA(V) uptake remains unknown. Recent studies have shown that arsenite is taken up by rice (Oryza sativa) roots through two silicon transporters, Lsi1 (the aquaporin NIP2;1) and Lsi2 (an efflux carrier). Here we investigated whether these two transporters also mediate the uptake of MMA(V) and DMA(V). MMA(V) was partly reduced to trivalent MMA(III) in rice roots, but only MMA(V) was translocated to shoots. DMA(V) was stable in plants. The rice lsi1 mutant lost about 80% and 50% of the uptake capacity for MMA(V) and DMA(V), respectively, compared with the wild-type rice, whereas Lsi2 mutation had little effect. The short-term uptake kinetics of MMA(V) can be described by a Michaelis-Menten plus linear model, with the wild type having 3.5-fold higher V(max) than the lsi1 mutant. The uptake kinetics of DMA(V) were linear with the slope being 2.8-fold higher in the wild type than the lsi1 mutant. Heterologous expression of Lsi1 in Xenopus laevis oocytes significantly increased the uptake of MMA(V) but not DMA(V), possibly because of a very limited uptake of the latter. Uptake of MMA(V) and DMA(V) by wild-type rice was increased as the pH of the medium decreased, consistent with an increasing proportion of the undissociated species. The results demonstrate that Lsi1 mediates the uptake of undissociated methylated As in rice roots.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 13
Claim · model-written summary
MMA(V) was partly reduced to MMA(III) in rice roots.
- Taxon
- rice
Oryza sativae0 - Organ / stage
- rootse0
- Outcome
- MMA(V) was partly reduced to trivalent MMA(III) in rice rootse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“MMA(V) was partly reduced to trivalent MMA(III) in rice roots, but only MMA(V) was translocated to shoots.”
Claim · model-written summary
Only MMA(V) was translocated to shoots.
- Taxon
- riceOryza sativae0
- Organ / stage
- shootse0
- Outcome
- MMA(V) was translocated to shootse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“MMA(V) was partly reduced to trivalent MMA(III) in rice roots, but only MMA(V) was translocated to shoots.”
Claim · model-written summary
DMA(V) was stable in plants.
- Taxon
- RiceOryza sativat0
- Outcome
- DMA(V) was stable in plantse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Rice”
e0“DMA(V) was stable in plants.”
Claim · model-written summary
The lsi1 mutant lost about 80% of MMA(V) uptake versus wild type.
- Taxon
- riceOryza sativae0
- Material
- rice lsi1 mutante0
- Treatment
- lsi1 mutante0
- Gene
- lsi1e0
- Outcome
- uptake capacity for MMA(V)e0
- Direction
- loste0
- Value
- about 80%e0
- Comparator
- wild-type ricee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The rice lsi1 mutant lost about 80% and 50% of the uptake capacity for MMA(V) and DMA(V), respectively, compared with the wild-type rice, whereas Lsi2 mutation had little effect.”
Claim · model-written summary
The lsi1 mutant lost 50% of DMA(V) uptake versus wild type.
- Taxon
- riceOryza sativae0
- Material
- rice lsi1 mutante0
- Treatment
- lsi1 mutante0
- Gene
- lsi1e0
- Outcome
- DMA(V)e0
- Direction
- loste0
- Value
- 50%e0
- Comparator
- wild-type ricee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The rice lsi1 mutant lost about 80% and 50% of the uptake capacity for MMA(V) and DMA(V), respectively, compared with the wild-type rice, whereas Lsi2 mutation had little effect.”
Claim · model-written summary
Lsi2 mutation had little effect on methylated arsenic uptake.
- Taxon
- riceOryza sativae0
- Treatment
- Lsi2 mutatione0
- Gene
- Lsi2e0
- Outcome
- uptake capacity for MMA(V) and DMA(V)e0
- Direction
- little effecte0
- Comparator
- wild-type ricee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The rice lsi1 mutant lost about 80% and 50% of the uptake capacity for MMA(V) and DMA(V), respectively, compared with the wild-type rice, whereas Lsi2 mutation had little effect.”
Claim · model-written summary
Wild type had 3.5-fold higher V(max) for MMA(V) uptake than lsi1.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The short-term uptake kinetics of MMA(V) can be described by a Michaelis-Menten plus linear model, with the wild type having 3.5-fold higher V(max) than the lsi1 mutant.”
t0“Rice”
Claim · model-written summary
DMA(V) uptake slope was 2.8-fold higher in wild type than lsi1.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The uptake kinetics of DMA(V) were linear with the slope being 2.8-fold higher in the wild type than the lsi1 mutant.”
t0“Rice”
Claim · model-written summary
Lsi1 expression in oocytes increased MMA(V) uptake.
- Taxon
- RiceOryza sativat0
- Treatment
- Heterologous expression of Lsi1 in Xenopus laevis oocytese0
- Gene
- Lsi1e0
- Outcome
- uptake of MMA(V)e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Rice”
e0“Heterologous expression of Lsi1 in Xenopus laevis oocytes significantly increased the uptake of MMA(V) but not DMA(V), possibly because of a very limited uptake of the latter.”
Claim · model-written summary
Lsi1 expression in oocytes did not significantly increase DMA(V) uptake.
- Taxon
- RiceOryza sativat0
- Treatment
- Heterologous expression of Lsi1 in Xenopus laevis oocytese0
- Gene
- Lsi1e0
- Outcome
- DMA(V)e0
- Qualifier
- possibly because of a very limited uptake of the lattere0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Rice”
e0“Heterologous expression of Lsi1 in Xenopus laevis oocytes significantly increased the uptake of MMA(V) but not DMA(V), possibly because of a very limited uptake of the latter.”
Claim · model-written summary
Lower medium pH increased MMA(V) uptake in wild-type rice.
- Taxon
- riceOryza sativae0
- Material
- wild-type ricee0
- Treatment
- pH of the medium decreasede0
- Outcome
- Uptake of MMA(V)e0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Uptake of MMA(V) and DMA(V) by wild-type rice was increased as the pH of the medium decreased, consistent with an increasing proportion of the undissociated species.”
Claim · model-written summary
Lower medium pH increased DMA(V) uptake in wild-type rice.
- Taxon
- riceOryza sativae0
- Material
- wild-type ricee0
- Treatment
- pH of the medium decreasede0
- Outcome
- DMA(V)e0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Uptake of MMA(V) and DMA(V) by wild-type rice was increased as the pH of the medium decreased, consistent with an increasing proportion of the undissociated species.”
Claim · model-written summary
Lsi1 mediates uptake of undissociated methylated arsenic in rice roots.
- Taxon
- riceOryza sativae0
- Gene
- Lsi1e0
- Outcome
- uptake of undissociated methylated As in rice rootse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results demonstrate that Lsi1 mediates the uptake of undissociated methylated As in rice roots.”
The same questions in other papers
overexpression · nutrient: content · Oryza sativa (rice)Positive and negative results
4 papers in the same direction as this paper · 1 in the opposite direction
- no effect
- positive
- positive
2 papers more in this group
See all 6 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.