A role for human Dicer in pre-RISC loading of siRNAs.
Nucleic Acids Res
; 39(4): 1510-25, 2011 Mar.
Article
em En
| MEDLINE
| ID: mdl-20972213
ABSTRACT
RNA interference is a powerful mechanism for sequence-specific inhibition of gene expression. It is widely known that small interfering RNAs (siRNAs) targeting the same region of a target-messenger RNA can have widely different efficacies. In efforts to better understand the siRNA features that influence knockdown efficiency, we analyzed siRNA interactions with a high-molecular weight complex in whole cell extracts prepared from two different cell lines. Using biochemical tools to study the nature of the complex, our results demonstrate that the primary siRNA-binding protein in the whole cell extracts is Dicer. We find that Dicer is capable of discriminating highly functional versus poorly functional siRNAs by recognizing the presence of 2-nt 3' overhangs and the thermodynamic properties of 2-4 bp on both ends of effective siRNAs. Our results suggest a role for Dicer in pre-selection of effective siRNAs for handoff to Ago2. This initial selection is reflective of the overall silencing potential of an siRNA.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Complexo de Inativação Induzido por RNA
/
RNA Interferente Pequeno
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Interferência de RNA
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Ribonuclease III
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article