An OPR3-independent pathway uses 4,5-didehydrojasmonate for jasmonate synthesis.
Nat Chem Biol
; 14(2): 171-178, 2018 02.
Article
em En
| MEDLINE
| ID: mdl-29291349
ABSTRACT
Biosynthesis of the phytohormone jasmonoyl-isoleucine (JA-Ile) requires reduction of the JA precursor 12-oxo-phytodienoic acid (OPDA) by OPDA reductase 3 (OPR3). Previous analyses of the opr3-1 Arabidopsis mutant suggested an OPDA signaling role independent of JA-Ile and its receptor COI1; however, this hypothesis has been challenged because opr3-1 is a conditional allele not completely impaired in JA-Ile biosynthesis. To clarify the role of OPR3 and OPDA in JA-independent defenses, we isolated and characterized a loss-of-function opr3-3 allele. Strikingly, opr3-3 plants remained resistant to necrotrophic pathogens and insect feeding, and activated COI1-dependent JA-mediated gene expression. Analysis of OPDA derivatives identified 4,5-didehydro-JA in wounded wild-type and opr3-3 plants. OPR2 was found to reduce 4,5-didehydro-JA to JA, explaining the accumulation of JA-Ile and activation of JA-Ile-responses in opr3-3 mutants. Our results demonstrate that in the absence of OPR3, OPDA enters the ß-oxidation pathway to produce 4,5-ddh-JA as a direct precursor of JA and JA-Ile, thus identifying an OPR3-independent pathway for JA biosynthesis.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Doenças das Plantas
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Arabidopsis
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Ciclopentanos
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Oxilipinas
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Resistência à Doença
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Isoleucina
Limite:
Animals
Idioma:
En
Revista:
Nat Chem Biol
Assunto da revista:
BIOLOGIA
/
QUIMICA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Espanha