RNA polymerase V transcription guides ARGONAUTE4 to chromatin.
Nat Genet
; 41(5): 630-4, 2009 May.
Article
em En
| MEDLINE
| ID: mdl-19377477
ABSTRACT
Retrotransposons and repetitive DNA elements in eukaryotes are silenced by small RNA-directed heterochromatin formation. In Arabidopsis, this process involves 24-nt siRNAs that bind to ARGONAUTE4 (AGO4) and facilitate the targeting of complementary loci via unknown mechanisms. Nuclear RNA polymerase V (Pol V) is an RNA silencing enzyme recently shown to generate noncoding transcripts at loci silenced by 24-nt siRNAs. We show that AGO4 physically interacts with these Pol V transcripts and is thereby recruited to the corresponding chromatin. We further show that DEFECTIVE IN MERISTEM SILENCING3 (DMS3), a structural maintenance of chromosomes (SMC) hinge-domain protein, functions in the assembly of Pol V transcription initiation or elongation complexes. Collectively, our data suggest that AGO4 is guided to target loci through base-pairing of associated siRNAs with nascent Pol V transcripts.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Transcrição Gênica
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RNA Polimerases Dirigidas por DNA
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Cromatina
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Proteínas de Arabidopsis
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article