Abstract
Polyphenol oxidases (PPOs) play a pivotal role in plant immune responses by catalysing the oxidation of phenolic compounds into cytotoxic quinones and melanin and contributing to the fortification of cell walls. Despite their biological significance, the high expression of PPOs in potatoes is not desirable due to their promotion of tuber browning. This study elucidates the relationship between PPO activity and defense mechanisms against the diverse pathogens Ralstonia solanacearum (Rs) and Phytophthora infestans (Pi) while mitigating enzymatic browning. CRISPR/Cas-mediated editing of the tuber- and root-specific PPO genes in the 'Désirée' and 'Balatoni Rózsa' potato cultivars considerably reduced enzymatic activity and browning. Among four PPO-edited mutant lines, three exhibited increased susceptibility to Rs while responses to Pi remained unchanged, underscoring the importance of PPOs in resistance to Rs. The PPO knockouts resulted in significant shifts in metabolite and hormone profiles characterized by elevated levels of dihydrokaempferol, coniferyl alcohol and taxifolin among other metabolites in the roots of Rs-susceptible mutants. Additionally, reduced PPO activity in these lines correlated with increased concentrations of salicylic acid, jasmonic acid and several antimicrobial compounds and alterations in flavonoid regulation. These findings highlight the complex role of PPOs in plant defense, establishing a positive correlation between PPO activity and resistance to Rs, while offering insights into the trade-offs associated with PPO gene editing in potatoes.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. 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
PPO gene editing reduced enzymatic activity and browning in two potato cultivars.
- Taxon
- potato
Solanum tuberosume0 - Material
- 'Désirée' and 'Balatoni Rózsa'e0
- Treatment
- CRISPR/Cas-mediated editinge0
- Gene
- PPO genese0
- Outcome
- enzymatic activity and browninge0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“CRISPR/Cas-mediated editing of the tuber- and root-specific PPO genes in the 'Désirée' and 'Balatoni Rózsa' potato cultivars considerably reduced enzymatic activity and browning”
Claim · model-written summary
Three of four PPO-edited lines became more susceptible to Ralstonia solanacearum.
- Taxon
- potatoSolanum tuberosumt0
- Material
- PPO-edited mutant linese0
- Treatment
- PPO-editede0
- Interactor
- Ralstonia solanacearum
Ralstonia solanacearume1pathogen - Outcome
- susceptibility to Rse0
- Direction
- increasede0
- Value
- threee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“Among four PPO-edited mutant lines, three exhibited increased susceptibility to Rs while responses to Pi remained unchanged”
e1“Ralstonia solanacearum (Rs)”
Claim · model-written summary
PPO-edited lines showed unchanged responses to Phytophthora infestans.
- Taxon
- potatoSolanum tuberosumt0
- Treatment
- PPO-editede2
- Interactor
- Phytophthora infestans
Phytophthora infestanse1pathogen - Outcome
- responses to Pie0
- Direction
- unchangede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“responses to Pi remained unchanged”
e1“Phytophthora infestans (Pi)”
e2“Among four PPO-edited mutant lines, three exhibited increased susceptibility to Rs while responses to Pi remained unchanged”
Claim · model-written summary
PPO knockouts shifted metabolite and hormone profiles in roots of Rs-susceptible mutants.
- Taxon
- potatoSolanum tuberosumt0
- Organ / stage
- rootse0
- Treatment
- PPO knockoutse0
- Interactor
- Rse0pathogen
- Outcome
- metabolite and hormone profilese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“The PPO knockouts resulted in significant shifts in metabolite and hormone profiles characterized by elevated levels of dihydrokaempferol, coniferyl alcohol and taxifolin among other metabolites in the roots of Rs-susceptible mutants”
Claim · model-written summary
PPO knockouts elevated dihydrokaempferol, coniferyl alcohol and taxifolin levels in roots of Rs-susceptible mutants.
- Taxon
- potatoSolanum tuberosumt0
- Organ / stage
- rootse0
- Treatment
- PPO knockoutse0
- Interactor
- Rse0pathogen
- Outcome
- levels of dihydrokaempferol, coniferyl alcohol and taxifoline0
- Direction
- elevatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“The PPO knockouts resulted in significant shifts in metabolite and hormone profiles characterized by elevated levels of dihydrokaempferol, coniferyl alcohol and taxifolin among other metabolites in the roots of Rs-susceptible mutants”
Claim · model-written summary
Reduced PPO activity correlated with increased salicylic acid, jasmonic acid and antimicrobial compound concentrations.
- Taxon
- potatoSolanum tuberosumt0
- Gene
- PPOe0
- Outcome
- concentrations of salicylic acid, jasmonic acid and several antimicrobial compoundse0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“reduced PPO activity in these lines correlated with increased concentrations of salicylic acid, jasmonic acid and several antimicrobial compounds”
Claim · model-written summary
Reduced PPO activity correlated with alterations in flavonoid regulation.
- Taxon
- potatoSolanum tuberosumt0
- Gene
- PPOe0
- Outcome
- alterations in flavonoid regulatione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“reduced PPO activity in these lines correlated with increased concentrations of salicylic acid, jasmonic acid and several antimicrobial compounds and alterations in flavonoid regulation”
Claim · model-written summary
PPO activity was positively correlated with resistance to Rs.
- Taxon
- potatoSolanum tuberosumt0
- Interactor
- Ralstonia solanacearumRalstonia solanacearume1pathogen
- Gene
- PPOe0
- Outcome
- resistance to Rse0
- Direction
- positivee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“potato”
e0“establishing a positive correlation between PPO activity and resistance to Rs”
e1“Ralstonia solanacearum (Rs)”
The same questions in other papers
loss of function · physiology: enzyme activity · Solanum tuberosum (potato)Results agree
3 papers in the same direction as this paper
- positive
- 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.