The apple WD40 protein MdTTG1 interacts with bHLH but not MYB proteins to regulate anthocyanin accumulation.
J Plant Physiol
; 169(7): 710-7, 2012 May 01.
Article
em En
| MEDLINE
| ID: mdl-22405592
ABSTRACT
The abundance of anthocyanins and proanthocyanins in apples is tightly regulated by three classes of regulatory factors, MYB, bHLH and WD40 proteins, only some of which have been previously identified. In this study, we identified an apple WD40 protein (MdTTG1) that promotes the accumulation of anthocyanins. The biosynthetic genes required downstream in the flavonoid pathway were up-regulated when MdTTG1 was over-expressed in Arabidopsis. Consistent with its role as a transcriptional regulator, an MdTTG1-GFP fusion protein was observed only in the nucleus. We assayed the expression patterns of this gene in different organs and found that they were positively correlated with anthocyanin accumulation in the apple. Yeast two-hybrid and bimolecular fluorescence complementation assays demonstrated that MdTTG1 interacted with bHLH transcription factors (TFs) but not MYB protein, whereas bHLH was known to interact with MYB in apples. However, based on a ChIP assay, MdTTG1 does not appear to bind to the promoter of the anthocyanin biosynthetic genes MdDFR and MdUFGT. Taken together, these results suggest that the apple WD40 protein MdTTG1 interacts with bHLH but not MYB proteins to regulate anthocyanin accumulation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
/
Fatores de Transcrição
/
Regulação da Expressão Gênica de Plantas
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Malus
/
Antocianinas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Plant Physiol
Ano de publicação:
2012
Tipo de documento:
Article