Abstract
Protease inhibitors (PIs) function in the precise regulation of proteases, and are thus involved in diverse biological processes in many organisms. Here, we studied the functions of the Arabidopsis UNUSUAL SERINE PROTEASE INHIBITOR (UPI) gene, which encodes an 8.8 kDa protein of atypical sequence relative to other PIs. Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni. Further, ectopic expression conferred increased resistance to B. cinerea and T. ni. In contrast, the mutant has wild-type responses to virulent, avirulent and non-pathogenic strains of Pseudomonas syringae, thus limiting the defense function of UPI to necrotrophic fungal infection and insect herbivory. Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression. The upi mutant also shows significantly delayed flowering, associated with decreased SOC1 expression and elevated levels of MAF1, two regulators of floral transition. Recombinant UPI strongly inhibits the serine protease chymotrypsin but also weakly blocks the cysteine protease papain. Interestingly, jasmonate induces intra- and extracellular UPI accumulation, suggesting a possible role in intercellular or extracellular functions. Overall, our results show that UPI is a dual-specificity PI that functions in plant growth and defense, probably through the regulation of endogenous proteases and/or those of biotic invaders.
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Claims 18
Claim · model-written summary
Arabidopsis UPI encodes an atypical 8.8 kDa protein.
- Taxon
- Arabidopsis
Arabidopsise0 - Gene
- UNUSUAL SERINE PROTEASE INHIBITORe0
- Outcome
- protein of atypical sequencee0
- Value
- 8.8 kDae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Here, we studied the functions of the Arabidopsis UNUSUAL SERINE PROTEASE INHIBITOR (UPI) gene, which encodes an 8.8 kDa protein of atypical sequence relative to other PIs.”
Claim · model-written summary
UPI loss increased susceptibility to Botrytis cinerea.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- loss-of-function UPI allelee0
- Interactor
- Botrytis cinerea
Botrytis cinereae0pathogen - Outcome
- susceptibilitye0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni.”
t0“Arabidopsis”
Claim · model-written summary
UPI loss increased susceptibility to Alternaria brassicicola.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- loss-of-function UPI allelee0
- Interactor
- Alternaria brassicicola
Alternaria brassicicolae0pathogen - Outcome
- susceptibilitye0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni.”
t0“Arabidopsis”
Claim · model-written summary
UPI loss increased susceptibility to Trichoplusia ni.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- loss-of-function UPI allelee0
- Interactor
- Trichoplusia ni
Trichoplusia nie0herbivore - Outcome
- susceptibilitye0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni.”
t0“Arabidopsis”
Claim · model-written summary
Ectopic UPI expression increased resistance to B. cinerea.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- ectopic expressione0
- Interactor
- B. cinereaBotrytis cinereae0pathogen
- Outcome
- resistancee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Further, ectopic expression conferred increased resistance to B. cinerea and T. ni.”
t0“Arabidopsis”
Claim · model-written summary
Ectopic UPI expression increased resistance to T. ni.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- ectopic expressione0
- Interactor
- T. nie0herbivore
- Outcome
- resistancee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Further, ectopic expression conferred increased resistance to B. cinerea and T. ni.”
t0“Arabidopsis”
Claim · model-written summary
The mutant responded like wild type to all reported Pseudomonas syringae strain categories.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- mutante0
- Interactor
- Pseudomonas syringae
Pseudomonas syringaee0pathogen - Outcome
- responsese0
- Direction
- wild-typee0
- Qualifier
- virulent, avirulent and non-pathogenic strainse0
- Comparator
- wild-typee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In contrast, the mutant has wild-type responses to virulent, avirulent and non-pathogenic strains of Pseudomonas syringae, thus limiting the defense function of UPI to necrotrophic fungal infection and insect herbivory.”
t0“Arabidopsis”
Claim · model-written summary
Jasmonate significantly induced UPI expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- jasmonatee0
- Gene
- UPIe0
- Outcome
- Expression of UPIe0
- Direction
- inducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression.”
t0“Arabidopsis”
Claim · model-written summary
Salicylic acid significantly induced UPI expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- salicylic acide0
- Gene
- UPIe0
- Outcome
- Expression of UPIe0
- Direction
- inducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression.”
t0“Arabidopsis”
Claim · model-written summary
Abscisic acid significantly induced UPI expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- abscisic acide0
- Gene
- UPIe0
- Outcome
- Expression of UPIe0
- Direction
- inducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression.”
t0“Arabidopsis”
Claim · model-written summary
Ethylene repressed UPI expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- ethylenee0
- Gene
- UPIe0
- Outcome
- Expression of UPIe0
- Direction
- repressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression.”
t0“Arabidopsis”
Claim · model-written summary
The upi mutant showed significantly delayed flowering.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- upi mutante0
- Outcome
- floweringe0
- Direction
- delayede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The upi mutant also shows significantly delayed flowering, associated with decreased SOC1 expression and elevated levels of MAF1, two regulators of floral transition.”
t0“Arabidopsis”
Claim · model-written summary
Delayed flowering was associated with decreased SOC1 expression.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- upi mutante0
- Gene
- SOC1e0
- Outcome
- SOC1 expressione0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The upi mutant also shows significantly delayed flowering, associated with decreased SOC1 expression and elevated levels of MAF1, two regulators of floral transition.”
t0“Arabidopsis”
Claim · model-written summary
Delayed flowering was associated with elevated MAF1 levels.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- upi mutante0
- Gene
- MAF1e0
- Outcome
- levels of MAF1e0
- Direction
- elevatede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The upi mutant also shows significantly delayed flowering, associated with decreased SOC1 expression and elevated levels of MAF1, two regulators of floral transition.”
t0“Arabidopsis”
Claim · model-written summary
Recombinant UPI strongly inhibited chymotrypsin.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- Recombinant UPIe0
- Gene
- chymotrypsine0
- Outcome
- serine protease chymotrypsine0
- Direction
- inhibitse0
- Qualifier
- stronglye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Recombinant UPI strongly inhibits the serine protease chymotrypsin but also weakly blocks the cysteine protease papain.”
t0“Arabidopsis”
Claim · model-written summary
Recombinant UPI weakly blocked papain.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- Recombinant UPIe0
- Gene
- papaine0
- Outcome
- cysteine protease papaine0
- Direction
- blockse0
- Qualifier
- weaklye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Recombinant UPI strongly inhibits the serine protease chymotrypsin but also weakly blocks the cysteine protease papain.”
t0“Arabidopsis”
Claim · model-written summary
Jasmonate induced intracellular and extracellular UPI accumulation.
- Taxon
- ArabidopsisArabidopsist0
- Treatment
- jasmonatee0
- Gene
- UPIe0
- Outcome
- intra- and extracellular UPI accumulatione0
- Direction
- inducese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Interestingly, jasmonate induces intra- and extracellular UPI accumulation, suggesting a possible role in intercellular or extracellular functions.”
t0“Arabidopsis”
Claim · model-written summary
UPI probably functions in growth and defense by regulating endogenous or invader proteases.
- Taxon
- ArabidopsisArabidopsist0
- Gene
- UPIe0
- Outcome
- plant growth and defensee0
- Qualifier
- probably through the regulation of endogenous proteases and/or those of biotic invaderse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Overall, our results show that UPI is a dual-specificity PI that functions in plant growth and defense, probably through the regulation of endogenous proteases and/or those of biotic invaders.”
t0“Arabidopsis”
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