ZmMYB31 directly represses maize lignin genes and redirects the phenylpropanoid metabolic flux.
Plant J
; 64(4): 633-44, 2010 Nov.
Article
em En
| MEDLINE
| ID: mdl-21070416
ABSTRACT
Few regulators of phenylpropanoids have been identified in monocots having potential as biofuel crops. Here we demonstrate the role of the maize (Zea mays) R2R3-MYB factor ZmMYB31 in the control of the phenylpropanoid pathway. We determined its in vitro consensus DNA-binding sequence as ACC(T)/(A) ACC, and chromatin immunoprecipitation (ChIP) established that it interacts with two lignin gene promoters in vivo. To explore the potential of ZmMYB31 as a regulator of phenylpropanoids in other plants, its role in the regulation of the phenylpropanoid pathway was further investigated in Arabidopsis thaliana. ZmMYB31 downregulates several genes involved in the synthesis of monolignols and transgenic plants are dwarf and show a significantly reduced lignin content with unaltered polymer composition. We demonstrate that these changes increase cell wall degradability of the transgenic plants. In addition, ZmMYB31 represses the synthesis of sinapoylmalate, resulting in plants that are more sensitive to UV irradiation, and induces several stress-related proteins. Our results suggest that, as an indirect effect of repression of lignin biosynthesis, transgenic plants redirect carbon flux towards the biosynthesis of anthocyanins. Thus, ZmMYB31 can be considered a good candidate for the manipulation of lignin biosynthesis in biotechnological applications.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Parede Celular
/
Regiões Promotoras Genéticas
/
Regulação da Expressão Gênica de Plantas
/
Zea mays
/
Lignina
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Plant J
Assunto da revista:
BIOLOGIA MOLECULAR
/
BOTANICA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Espanha