Abstract
Plants that have been wounded by insects or other herbivores may be more susceptible to infection by adventitious microbes. Wound-induced signal molecules, which serve to induce responses in the plant that retard further feeding, might also act to prepare a plant for possible pathogen attack. We have examined the effect of a wound-generated systemic messenger (systemin) on a pathogen-stimulated defense-response marker, the oxidative burst. We observed that neither systemin nor its inactive analog (A-17) was able to directly induce H2O2 biosynthesis in suspension-cultured tomato (Lycopersicon esculentum L.) cells, regardless of the duration of exposure of the cells to the two peptides. Similarly, neither systemin nor A-17 was capable of modifying an oligogalacturonide-elicited oxidative burst, as long as elicitor addition occurred within minutes of treatment with systemin or A-17. In contrast, preexposure of the cell cultures to systemin (but not to A-17) led to a time-dependent enhancement of the oligogalacturonide-elicited oxidative burst. By 12 h of exposure, the H2O2 biosynthetic capacity of systemin-treated cells exceeded that of the control cells by a factor of 16 +/- 2. A similar up-regulation by systemin of a mechanically stimulated oxidative burst was also observed. Because the systemin-induced augmentation in oxidant synthesis is quantitatively prevented by coincubation with 2 &mgr;M cycloheximide, and because the oxidative burst of oligogalacturonic acid-elicited control cells (no systemin exposure) is unaffected by preincubation with cycloheximide, we conclude that systemin enhancement of the tomato-cell oxidative burst requires protein synthesis.
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 8
Claim · model-written summary
Neither systemin nor A-17 directly induced peroxide biosynthesis.
- Taxon
- tomato
Solanum lycopersicume0 - Treatment
- systemin nor its inactive analog (A-17)e0
- Outcome
- H2O2 biosynthesise0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“neither systemin nor its inactive analog (A-17) was able to directly induce H2O2 biosynthesis in suspension-cultured tomato (Lycopersicon esculentum L.) cells”
Claim · model-written summary
Immediate systemin or A-17 treatment did not modify elicited oxidative bursts.
Not reportedTaxonComparatorDirection
Verbatim
e0“neither systemin nor A-17 was capable of modifying an oligogalacturonide-elicited oxidative burst”
Claim · model-written summary
Systemin preexposure enhanced elicited bursts over time.
- Treatment
- systemine0
- Outcome
- oligogalacturonide-elicited oxidative burste0
- Direction
- enhancemente0
- Comparator
- A-17e0
Not reportedTaxon
Verbatim
e0“preexposure of the cell cultures to systemin (but not to A-17) led to a time-dependent enhancement of the oligogalacturonide-elicited oxidative burst.”
Claim · model-written summary
By 12 hours, systemin treated cells had 16 ± 2 times control peroxide biosynthesis capacity.
- Treatment
- systemin-treatede0
- Outcome
- H2O2 biosynthetic capacitye0
- Direction
- exceedede0
- Value
- 16 +/- 2e0
- Comparator
- control cellse0
Not reportedTaxon
Verbatim
e0“By 12 h of exposure, the H2O2 biosynthetic capacity of systemin-treated cells exceeded that of the control cells by a factor of 16 +/- 2.”
Claim · model-written summary
Systemin increased mechanically stimulated oxidative burst.
Not reportedTaxonComparator
Verbatim
e0“A similar up-regulation by systemin of a mechanically stimulated oxidative burst was also observed.”
Claim · model-written summary
Cycloheximide prevented systemin enhanced oxidant synthesis.
- Treatment
- 2 &mgr;M cycloheximidee0
- Outcome
- systemin-induced augmentation in oxidant synthesise0
- Direction
- preventede0
Not reportedTaxonComparator
Verbatim
e0“systemin-induced augmentation in oxidant synthesis is quantitatively prevented by coincubation with 2 &mgr;M cycloheximide”
Claim · model-written summary
Control elicited bursts were unaffected by cycloheximide.
Not reportedTaxonComparator
Verbatim
e0“oxidative burst of oligogalacturonic acid-elicited control cells (no systemin exposure) is unaffected by preincubation with cycloheximide”
Claim · model-written summary
Authors infer protein synthesis is required for systemin enhancement.
- Taxon
- tomatoSolanum lycopersicume0
- Outcome
- oxidative burste0
- Qualifier
- protein synthesise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“systemin enhancement of the tomato-cell oxidative burst requires protein synthesis.”
The same questions in other papers
cycloheximide · molecular: metabolites · Solanum lycopersicum (tomato)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- positive
- no effect
- negative
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.