Abstract
cDNAs encoding a high-affinity sulfate transporter and an adenosine 5'-phosphosulfate reductase from potato (Solanum tuberosum L. cv Desiree) have been cloned and used to examine the hypothesis that sulfate uptake and assimilation is transcriptionally regulated and that this is mediated via intracellular O-acetylserine (OAS) pools. Gas chromotography coupled to mass spectrometry was used to quantify OAS and its derivative, N-acetylserine. Treatment with external OAS increased sulfate transporter and adenosine 5'-phosphosulfate reductase gene expression consistent with a model of transcriptional induction by OAS. To investigate this further, the Escherichia coli gene cysE (serine acetyltransferase EC 2.3.1.30), which synthesizes OAS, has been expressed in potato to modify internal metabolite pools. Transgenic lines, with increased cysteine and glutathione pools, particularly in the leaves, had increased sulfate transporter expression in the roots. However, the small increases in the OAS pools were not supportive of the hypothesis that this molecule is the signal of sulfur (S) nutritional status. In addition, although during S starvation the content of S-containing compounds decreased (consistent with derepression as a mechanism of regulation), OAS pools increased only following extended starvation, probably as a consequence of the S starvation. Taken together, expression of these genes may be induced by a demand-driven model, via a signal from the shoots, which is not OAS. Rather, the signal may be the depletion of intermediates of the sulfate assimilation pathway, such as sulfide, in the roots. Finally, sulfate transporter activity did not increase in parallel with transcript and protein abundance, indicating additional posttranslational regulatory mechanisms.
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 7
Claim · model-written summary
External OAS increased sulfate transporter and reductase gene expression.
- Taxon
- potato
Solanum tuberosume1 - Treatment
- external OASe0
- Outcome
- sulfate transporter and adenosine 5'-phosphosulfate reductase gene expressione0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatment with external OAS increased sulfate transporter and adenosine 5'-phosphosulfate reductase gene expression consistent with a model of transcriptional induction by OAS.”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
Transgenic lines had increased cysteine and glutathione pools, especially in leaves.
- Taxon
- potatoSolanum tuberosume1
- Material
- Transgenic linese0
- Organ / stage
- leavese0
- Outcome
- cysteine and glutathione poolse0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transgenic lines, with increased cysteine and glutathione pools, particularly in the leaves, had increased sulfate transporter expression in the roots.”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
Transgenic lines showed increased root sulfate transporter expression.
- Taxon
- potatoSolanum tuberosume1
- Material
- Transgenic linese0
- Organ / stage
- rootse0
- Outcome
- sulfate transporter expressione0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Transgenic lines, with increased cysteine and glutathione pools, particularly in the leaves, had increased sulfate transporter expression in the roots.”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
OAS pools increased only slightly in the transgenic lines.
- Taxon
- potatoSolanum tuberosume1
- Outcome
- OAS poolse0
- Direction
- small increasese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“However, the small increases in the OAS pools were not supportive of the hypothesis that this molecule is the signal of sulfur (S) nutritional status.”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
Sulfur starvation decreased sulfur-containing compound content.
- Taxon
- potatoSolanum tuberosume1
- Treatment
- S starvatione0
- Outcome
- content of S-containing compoundse0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“during S starvation the content of S-containing compounds decreased”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
OAS pools increased only after extended sulfur starvation.
- Taxon
- potatoSolanum tuberosume1
- Treatment
- extended starvatione0
- Outcome
- OAS poolse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“OAS pools increased only following extended starvation”
e1“potato (Solanum tuberosum L. cv Desiree)”
Claim · model-written summary
Sulfate transporter activity failed to rise in parallel with transcript and protein abundance.
- Taxon
- potatoSolanum tuberosume1
- Gene
- sulfate transportere0
- Outcome
- sulfate transporter activitye0
- Direction
- did not increasee0
- Qualifier
- transcript and protein abundancee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“sulfate transporter activity did not increase in parallel with transcript and protein abundance”
e1“potato (Solanum tuberosum L. cv Desiree)”
The same questions in other papers
sulfur atom · molecular: metabolites · Solanum tuberosum (potato)Results agree
6 papers in the same direction as this paper
This paper is about lacking the nutrient, so it counts the other way round here.
- positive
- positive
- positive
3 papers more in this group
See all 7 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.