Abstract
Tomato plants overexpressing a prosystemin gene that encodes the precursor of a mobile wound signal called systemin have been shown previously to constitutively synthesize extraordinarily high levels of two defensive proteinase inhibitor proteins in leaves in the absence of wounding. We herein report that leaves of these transgenic plants possess enhanced levels of another defensive protein, polyphenol oxidase (PPO) at levels that are up to 70-fold higher than levels found in leaves of wild-type plants. Supplying young wild-type tomato plants with systemin through cut stems induced PPO activity in leaves, and wounding lower leaves of young tomato plants induced PPO activity in both wounded and unwounded leaves to levels equal to those induced by systemin. Exposing young tomato plants to methyl jasmonate vapor caused an increase in PPO activity equivalent to levels found in plants overexpressing the prosystemin gene. The data indicate that PPO and proteinase inhibitor genes are coactivated systemically by wounding via the octadecanoid signal transduction pathway and that systemin has a much broader role in signaling plant defensive genes than was previously known.
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Claims 6
Claim · model-written summary
Leaves of prosystemin-overexpressing tomato plants have polyphenol oxidase levels up to 70-fold higher than wild-type leaves.
- Taxon
- tomato
Solanum lycopersicumt0 - Treatment
- overexpressing a prosystemin genee0
- Gene
- prosystemine0
- Outcome
- polyphenol oxidase (PPO)e1
- Direction
- highere1
- Value
- 70-folde1
- Comparator
- wild-type plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e0“Tomato plants overexpressing a prosystemin gene”
e1“leaves of these transgenic plants possess enhanced levels of another defensive protein, polyphenol oxidase (PPO) at levels that are up to 70-fold higher than levels found in leaves of wild-type plants”
Claim · model-written summary
Systemin supplied through cut stems to young wild-type tomato plants induced PPO activity in leaves.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- systemin through cut stemse2
- Outcome
- PPO activitye2
- Direction
- inducede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e2“Supplying young wild-type tomato plants with systemin through cut stems induced PPO activity in leaves”
Claim · model-written summary
Wounding lower leaves of young tomato plants induced PPO activity in wounded and unwounded leaves to levels equal to those induced by systemin.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- wounding lower leavese3
- Outcome
- PPO activitye3
- Direction
- inducede3
- Qualifier
- to levels equal to those induced by systemine3
- Comparator
- systemine3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e3“wounding lower leaves of young tomato plants induced PPO activity in both wounded and unwounded leaves to levels equal to those induced by systemin”
Claim · model-written summary
Methyl jasmonate vapor increased PPO activity in young tomato plants to levels equivalent to prosystemin-overexpressing plants.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- methyl jasmonate vapore4
- Outcome
- PPO activitye4
- Direction
- increasee4
- Comparator
- plants overexpressing the prosystemin genee4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e4“Exposing young tomato plants to methyl jasmonate vapor caused an increase in PPO activity equivalent to levels found in plants overexpressing the prosystemin gene”
Claim · model-written summary
PPO and proteinase inhibitor genes are coactivated systemically by wounding via the octadecanoid signal transduction pathway.
- Taxon
- tomatoSolanum lycopersicumt0
- Treatment
- woundinge5
- Gene
- PPO and proteinase inhibitor genese5
- Outcome
- coactivatede5
- Qualifier
- via the octadecanoid signal transduction pathwaye5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e5“PPO and proteinase inhibitor genes are coactivated systemically by wounding via the octadecanoid signal transduction pathway”
Claim · model-written summary
Systemin has a broader role in signalling plant defensive genes than previously known.
- Taxon
- tomatoSolanum lycopersicumt0
- Compound
- systemine6
- Outcome
- signaling plant defensive genese6
- Qualifier
- than was previously knowne6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tomato leaf polyphenol oxidase”
e6“systemin has a much broader role in signaling plant defensive genes than was previously known”
The same questions in other papers
mechanical · physiology: antioxidant enzymes · Solanum lycopersicum (tomato)Results agree
2 papers in the same direction as this paper
- positive
- positive
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.