Abstract
Systemin is a wound-signaling peptide that mediates defenses of tomato plants against herbivorous insects. Perception of systemin by the membrane-bound receptor SR160 results in activation of MAPKs, synthesis of jasmonic acid (JA), and expression of defense genes. To test the function of MAPKs in the response to systemin, we used virus-induced gene silencing (VIGS) in plants that overexpress the systemin precursor prosystemin (35S::prosys plants). These transgenic plants accumulate high levels of defense proteins and exhibit increased resistance to herbivorous insects. Cosilencing of the MAPKs MPK1 and MPK2 reduced MPK1/2 kinase activity, JA biosynthesis, and expression of JA-dependent defense genes. Application of methyl-JA restored the full defense response. These data show that MPK1 and MPK2 are essential components of the systemin signaling pathway and most likely function upstream of JA biosynthesis. MPK1 and MPK2 are 95% identical at the amino acid level. Specific VIGS of only MPK1 or MPK2 resulted in the same reduction of defense gene expression as cosilencing of MPK1 and MPK2, indicating that gene dosage effects may be important for MPK signaling. In addition, VIGS of the closely related MPK3 also reduced systemin-induced defense responses. The function of MPK1/2 and orthologs in pathogen-induced defenses is well established. Here we show that cosilencing of MPK1 and MPK2 compromised prosystemin-mediated resistance to Manduca sexta (Lepidoptera) herbivory, demonstrating that MPK1 and MPK2 are also required for successful defenses against herbivorous insects.
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 11
Claim · model-written summary
Prosystemin overexpressing tomato plants accumulated high defense protein levels.
- Taxon
- Tomato
Solanum lycopersicumt0 - Material
- These transgenic plantse0
- Outcome
- high levels of defense proteinse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“These transgenic plants accumulate high levels of defense proteins”
Claim · model-written summary
Prosystemin overexpressing tomato plants had increased resistance to herbivorous insects.
- Taxon
- TomatoSolanum lycopersicumt0
- Interactor
- herbivorous insectse0herbivore
- Outcome
- resistance to herbivorous insectse0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“exhibit increased resistance to herbivorous insects”
Claim · model-written summary
Cosilencing MPK1 and MPK2 reduced MPK1/2 kinase activity in tomato.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Cosilencing of the MAPKs MPK1 and MPK2e0
- Gene
- MPK1 and MPK2e0
- Outcome
- MPK1/2 kinase activitye0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Cosilencing of the MAPKs MPK1 and MPK2 reduced MPK1/2 kinase activity”
Claim · model-written summary
Cosilencing MPK1 and MPK2 reduced JA biosynthesis in tomato.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Cosilencing of the MAPKs MPK1 and MPK2e0
- Gene
- MPK1 and MPK2e0
- Outcome
- JA biosynthesise0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Cosilencing of the MAPKs MPK1 and MPK2 reduced MPK1/2 kinase activity, JA biosynthesis”
Claim · model-written summary
Cosilencing MPK1 and MPK2 reduced expression of JA dependent defense genes in tomato.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Cosilencing of the MAPKs MPK1 and MPK2e0
- Gene
- MPK1 and MPK2e0
- Outcome
- expression of JA-dependent defense genese0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Cosilencing of the MAPKs MPK1 and MPK2 reduced MPK1/2 kinase activity, JA biosynthesis, and expression of JA-dependent defense genes”
Claim · model-written summary
Methyl JA application restored the full tomato defense response.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Application of methyl-JAe0
- Outcome
- full defense responsee0
- Direction
- restorede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Application of methyl-JA restored the full defense response”
Claim · model-written summary
MPK1 and MPK2 were 95% identical at the amino acid level.
- Taxon
- TomatoSolanum lycopersicumt0
- Gene
- MPK1 and MPK2e0
- Outcome
- identical at the amino acid levele0
- Value
- 95%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“MPK1 and MPK2 are 95% identical at the amino acid level”
Claim · model-written summary
Silencing MPK1 alone reduced defense gene expression to the same extent as cosilencing.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Specific VIGS of only MPK1e0
- Gene
- MPK1e0
- Outcome
- defense gene expressione0
- Direction
- reductione0
- Comparator
- cosilencing of MPK1 and MPK2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Specific VIGS of only MPK1 or MPK2 resulted in the same reduction of defense gene expression as cosilencing of MPK1 and MPK2”
Claim · model-written summary
Silencing MPK2 alone reduced defense gene expression to the same extent as cosilencing.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- MPK2e0
- Gene
- MPK2e0
- Outcome
- defense gene expressione0
- Direction
- reductione0
- Comparator
- cosilencing of MPK1 and MPK2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“Specific VIGS of only MPK1 or MPK2 resulted in the same reduction of defense gene expression as cosilencing of MPK1 and MPK2”
Claim · model-written summary
MPK3 silencing reduced systemin induced defense responses.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- VIGS of the closely related MPK3e0
- Gene
- MPK3e0
- Outcome
- systemin-induced defense responsese0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“VIGS of the closely related MPK3 also reduced systemin-induced defense responses”
Claim · model-written summary
MPK1 and MPK2 cosilencing compromised resistance to Manduca sexta herbivory.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- cosilencing of MPK1 and MPK2e0
- Interactor
- Manduca sexta
Manduca sextae0herbivore - Gene
- MPK1 and MPK2e0
- Outcome
- prosystemin-mediated resistance to Manduca sexta (Lepidoptera) herbivorye0
- Direction
- compromisede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tomato”
e0“cosilencing of MPK1 and MPK2 compromised prosystemin-mediated resistance to Manduca sexta (Lepidoptera) herbivory”
The same questions in other papers
loss of function · molecular: expression · Solanum lycopersicum (tomato)Positive and negative results
59 papers in the same direction as this paper · 20 in the opposite direction
- positive
- negative
- no effect
76 papers more in this group
See all 80 papers →loss of function · disease · Solanum lycopersicum (tomato)Positive and negative results
91 papers in the same direction as this paper · 63 in the opposite direction
- positive
- negative
- negative
151 papers more in this group
See all 155 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.