MYB20, MYB42, MYB43, and MYB85 Regulate Phenylalanine and Lignin Biosynthesis during Secondary Cell Wall Formation.
Plant Physiol
; 182(3): 1272-1283, 2020 03.
Article
em En
| MEDLINE
| ID: mdl-31871072
ABSTRACT
Lignin is a phenylpropanoid-derived polymer that functions as a major component of cell walls in plant vascular tissues. Biosynthesis of the aromatic amino acid Phe provides precursors for many secondary metabolites, including lignins and flavonoids. Here, we discovered that MYB transcription factors MYB20, MYB42, MYB43, and MYB85 are transcriptional regulators that directly activate lignin biosynthesis genes and Phe biosynthesis genes during secondary wall formation in Arabidopsis (Arabidopsis thaliana). Disruption of MYB20, MYB42, MYB43, and MYB85 resulted in growth development defects and substantial reductions in lignin biosynthesis. In addition, our data showed that these MYB proteins directly activated transcriptional repressors that specifically inhibit flavonoid biosynthesis, which competes with lignin biosynthesis for Phe precursors. Together, our results provide important insights into the molecular framework for the lignin biosynthesis pathway.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fenilalanina
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Fatores de Transcrição
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Parede Celular
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Arabidopsis
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Proteínas de Arabidopsis
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Lignina
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article