Transcriptional control of gene expression by microRNAs.
Cell
; 140(1): 111-22, 2010 Jan 08.
Article
em En
| MEDLINE
| ID: mdl-20085706
ABSTRACT
MicroRNAs (miRNAs) control gene expression in animals and plants. Like another class of small RNAs, siRNAs, they affect gene expression posttranscriptionally. While siRNAs in addition act in transcriptional gene silencing, a role of miRNAs in transcriptional regulation has been less clear. We show here that in moss Physcomitrella patens mutants without a DICER-LIKE1b gene, maturation of miRNAs is normal but cleavage of target RNAs is abolished and levels of these transcripts are drastically reduced. These mutants accumulate miRNAtarget-RNA duplexes and show hypermethylation of the genes encoding target RNAs, leading to gene silencing. This pathway occurs also in the wild-type upon hormone treatment. We propose that initiation of epigenetic silencing by DNA methylation depends on the ratio of the miRNA and its target RNA.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação da Expressão Gênica
/
RNA de Plantas
/
Bryopsida
/
MicroRNAs
Idioma:
En
Revista:
Cell
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Alemanha