Abstract
Mannitol, a sugar alcohol that appears to serve as an osmoprotectant/compatible solute to cope with salt stress, is synthesized in celery ( Apium graveolens L.) via the action of a NADPH dependent mannose-6-phosphate reductase (M6PR). To evaluate the abiotic stress effects of mannitol biosynthesis, we transformed celery with an antisense construct of the celery leaf M6PR gene under control of the CaMV 35S promoter. Unlike wild type (WT) celery, independent antisense M6PR transformants did not accumulate significant amounts of mannitol in any tissue, with or without salt stress. In the absence of NaCl, and despite the lack of any significant accumulation of mannitol that is normally the major photosynthetic product, antisense transformants were mostly phenotypically similar to the WT celery. However, in the presence of NaCl, mature antisense transgenic plants were significantly less salt-tolerant, with reduced growth and photosynthetic rates, and some transformant lines were killed at 200 mM NaCl, a concentration that WT celery can normally withstand. Although mannitol biosynthesis is normally enhanced in salt-treated WT celery, no such increase was observed in the antisense transformants. Like our previous gain of function results showing enhanced salt tolerance in Arabidopsis plants transgenic for a sense M6PR construct, these loss of function results, using an antisense construct in celery, demonstrate a major role for mannitol biosynthesis in developing salt-tolerant plants.
Abstract from the paper’s OpenAlex record; open copy licensed public-domain. 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 8
Claim · model-written summary
Antisense M6PR celery lines did not accumulate significant mannitol with or without salt stress.
- Taxon
- celery
%2C_Elswick%2C_Northumberland_4.jpg?width=60)
Apium graveolens Dulce Groupe0 - Material
- antisense M6PR transformantse0
- Treatment
- antisense M6PRe0
- Gene
- M6PRe0
- Outcome
- amounts of mannitole0
- Direction
- did not accumulatee0
- Qualifier
- with or without salt stresse0
- Comparator
- wild type (WT) celerye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
%2C_Elswick%2C_Northumberland_4.jpg?width=500)
Verbatim
e0“Unlike wild type (WT) celery, independent antisense M6PR transformants did not accumulate significant amounts of mannitol in any tissue, with or without salt stress.”
Claim · model-written summary
Without NaCl, antisense M6PR celery lines were mostly phenotypically similar to wild type.
- Taxon
- celeryApium graveolens Dulce Groupe0
- Treatment
- antisense transformantse0
- Gene
- M6PRe1
- Outcome
- phenotypically similare0
- Qualifier
- In the absence of NaCle0
- Comparator
- WT celerye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the absence of NaCl, and despite the lack of any significant accumulation of mannitol that is normally the major photosynthetic product, antisense transformants were mostly phenotypically similar to the WT celery.”
e1“antisense M6PR transformants”
Claim · model-written summary
Under NaCl, mature antisense celery lines were significantly less salt tolerant than wild type.
- Taxon
- celeryApium graveolens Dulce Groupe1
- Treatment
- antisense transgenic plantse0
- Outcome
- salt-tolerante0
- Direction
- lesse0
- Qualifier
- in the presence of NaCle0
- Comparator
- WT celerye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the presence of NaCl, mature antisense transgenic plants were significantly less salt-tolerant”
e1“a concentration that WT celery can normally withstand”
Claim · model-written summary
Under NaCl, antisense celery plants showed reduced growth.
- Taxon
- celeryApium graveolens Dulce Groupe1
- Treatment
- antisense transgenic plantse0
- Outcome
- growthe0
- Direction
- reducede0
- Qualifier
- in the presence of NaCle0
- Comparator
- WT celerye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the presence of NaCl, mature antisense transgenic plants were significantly less salt-tolerant, with reduced growth and photosynthetic rates”
e1“WT celery can normally withstand”
Claim · model-written summary
Under NaCl, antisense celery plants showed reduced photosynthetic rates.
- Taxon
- celeryApium graveolens Dulce Groupe1
- Treatment
- antisense transgenic plantse0
- Outcome
- photosynthetic ratese0
- Direction
- reducede0
- Qualifier
- in the presence of NaCle0
- Comparator
- WT celerye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the presence of NaCl, mature antisense transgenic plants were significantly less salt-tolerant, with reduced growth and photosynthetic rates”
e1“WT celery can normally withstand”
Claim · model-written summary
Some antisense celery lines were killed at 200 mM NaCl, which wild type normally withstands.
- Taxon
- celeryApium graveolens Dulce Groupe0
- Material
- transformant linese0
- Treatment
- 200 mM NaCle0
- Outcome
- transformant lines were killede0
- Comparator
- WT celerye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“some transformant lines were killed at 200 mM NaCl, a concentration that WT celery can normally withstand.”
Claim · model-written summary
Salt treatment enhanced mannitol biosynthesis in wild-type celery.
- Taxon
- celeryApium graveolens Dulce Groupe0
- Treatment
- salt-treatede0
- Outcome
- mannitol biosynthesise0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“mannitol biosynthesis is normally enhanced in salt-treated WT celery”
Claim · model-written summary
Salt treatment did not enhance mannitol biosynthesis in antisense celery lines.
- Taxon
- celeryApium graveolens Dulce Groupe0
- Material
- antisense transformantse0
- Treatment
- salt-treatede0
- Outcome
- mannitol biosynthesise0
- Direction
- no such increasee0
- Comparator
- WT celerye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Although mannitol biosynthesis is normally enhanced in salt-treated WT celery, no such increase was observed in the antisense transformants.”