Abstract
Disease spread of Pseudocercospora fijiensis, causal agent of the black Sigatoka disease of banana, depends on ascospores produced through the sexual reproductive cycle. We used phylogenetic analysis to identify P. fijiensis homologs (PKS8-4 and Hybrid8-3) to the PKS4 polyketide synthases (PKS) from Neurospora crassa and Sordaria macrospora involved in sexual reproduction. These sequences also formed a clade with lovastatin, compactin, and betaenone-producing PKS sequences. Transcriptome analysis showed that both the P. fijiensis Hybrid8-3 and PKS8-4 genes have higher expression in infected leaf tissue compared to in culture. Domain analysis showed that PKS8-4 is more similar than Hybrid8-3 to PKS4. pPKS8-4:GFP transcriptional fusion transformants showed expression of GFP in flask-shaped structures in mycelial cultures as well as in crosses between compatible and incompatible mating types. Confocal microscopy confirmed expression in spermagonia in leaf substomatal cavities, consistent with a role in sexual reproduction. A disruption mutant of pks8-4 retained normal pathogenicity on banana, and no differences were observed in growth, conidial production, and spermagonia production. GC-MS profiling of the mutant and wild type did not identify differences in polyketide metabolites, but did identify changes in saturated fatty acid methyl esters and alkene and alkane derivatives. To our knowledge, this is the first report of a polyketide synthase pathway associated with spermagonia.
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Claims 11
Claim · model-written summary
Phylogenetic analysis identified P. fijiensis PKS8-4 and Hybrid8-3 homologs.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensis
Pseudocercospora fijiensist0pathogen - Outcome
- P. fijiensis homologs (PKS8-4 and Hybrid8-3)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“identify P. fijiensis homologs (PKS8-4 and Hybrid8-3) to the PKS4 polyketide synthases (PKS) from Neurospora crassa and Sordaria macrospora”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
The homologs clustered with lovastatin, compactin and betaenone producing PKS sequences.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- formed a clade with lovastatin, compactin, and betaenone-producing PKS sequencese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“These sequences also formed a clade with lovastatin, compactin, and betaenone-producing PKS sequences.”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
Hybrid8-3 expression was higher in infected leaves than in culture.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Gene
- P. fijiensis Hybrid8-3e0
- Outcome
- higher expressione0
- Direction
- highere0
- Comparator
- in culturee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both the P. fijiensis Hybrid8-3 and PKS8-4 genes have higher expression in infected leaf tissue compared to in culture”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
PKS8-4 expression was higher in infected leaves than in culture.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Gene
- PKS8-4e0
- Outcome
- higher expressione0
- Direction
- highere0
- Comparator
- in culturee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both the P. fijiensis Hybrid8-3 and PKS8-4 genes have higher expression in infected leaf tissue compared to in culture”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
PKS8-4 domains resembled PKS4 more than Hybrid8-3 domains did.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Gene
- PKS8-4e0
- Outcome
- more similar than Hybrid8-3 to PKS4e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PKS8-4 is more similar than Hybrid8-3 to PKS4”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
Reporter expression occurred in flask-shaped mycelial structures and in crosses.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- expression of GFP in flask-shaped structurese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“pPKS8-4:GFP transcriptional fusion transformants showed expression of GFP in flask-shaped structures in mycelial cultures as well as in crosses between compatible and incompatible mating types.”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
Expression was confirmed in spermagonia within leaf substomatal cavities.
- Taxon
- bananat0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- expression in spermagonia in leaf substomatal cavitiese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Confocal microscopy confirmed expression in spermagonia in leaf substomatal cavities”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
Disrupting pks8-4 did not change pathogenicity on banana.
- Taxon
- bananae0
- Treatment
- disruption mutant of pks8-4e0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- pathogenicity on bananae0
- Direction
- retained normale0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A disruption mutant of pks8-4 retained normal pathogenicity on banana”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
The mutant showed no differences in growth, conidial production or spermagonia production.
- Taxon
- bananae0
- Treatment
- disruption mutant of pks8-4e0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- growth, conidial production, and spermagonia productione0
- Direction
- no differencese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A disruption mutant of pks8-4 retained normal pathogenicity on banana, and no differences were observed in growth, conidial production, and spermagonia production.”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
The mutant and wild type showed no difference in polyketide metabolites.
- Taxon
- bananat0
- Treatment
- mutante0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- polyketide metabolitese0
- Direction
- did not identify differencese0
- Comparator
- wild typee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“GC-MS profiling of the mutant and wild type did not identify differences in polyketide metabolites”
t0“banana pathogen, Pseudocercospora fijiensis”
Claim · model-written summary
The mutant and wild type differed in saturated fatty acid methyl esters and alkene and alkane derivatives.
- Taxon
- bananat0
- Treatment
- mutante0
- Interactor
- Pseudocercospora fijiensisPseudocercospora fijiensist0pathogen
- Outcome
- saturated fatty acid methyl esters and alkene and alkane derivativese0
- Direction
- changese0
- Comparator
- wild typee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“GC-MS profiling of the mutant and wild type did not identify differences in polyketide metabolites, but did identify changes in saturated fatty acid methyl esters and alkene and alkane derivatives.”
t0“banana pathogen, Pseudocercospora fijiensis”
The same questions in other papers
loss of function · Pseudocercospora fijiensis · MusaPositive and negative results
1 in the opposite direction
- 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.