Transcriptional and post-transcriptional regulation of a NAC1 transcription factor in Medicago truncatula roots.
New Phytol
; 191(3): 647-661, 2011 Aug.
Article
em En
| MEDLINE
| ID: mdl-21770944
ABSTRACT
⢠Legume roots develop two types of lateral organs, lateral roots and nodules. Nodules develop as a result of a symbiotic interaction with rhizobia and provide a niche for the bacteria to fix atmospheric nitrogen for the plant. ⢠The Arabidopsis NAC1 transcription factor is involved in lateral root formation, and is regulated post-transcriptionally by miRNA164 and by SINAT5-dependent ubiquitination. We analyzed in Medicago truncatula the role of the closest NAC1 homolog in lateral root formation and in nodulation. ⢠MtNAC1 shows a different expression pattern in response to auxin than its Arabidopsis homolog and no changes in lateral root number or nodulation were observed in plants affected in MtNAC1 expression. In addition, no interaction was found with SINA E3 ligases, suggesting that post-translational regulation of MtNAC1 does not occur in M. truncatula. Similar to what was found in Arabidopsis, a conserved miR164 target site was retrieved in MtNAC1, which reduced protein accumulation of a GFP-miR164 sensor. Furthermore, miR164 and MtNAC1 show an overlapping expression pattern in symbiotic nodules, and overexpression of this miRNA led to a reduction in nodule number. ⢠This work suggests that regulatory pathways controlling a conserved transcription factor are complex and divergent between M. truncatula and Arabidopsis.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
/
Fatores de Transcrição
/
Sinorhizobium meliloti
/
Medicago truncatula
Idioma:
En
Revista:
New Phytol
Assunto da revista:
BOTANICA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Bélgica