Molecular Basis for the Single-Nucleotide Precision of Primary microRNA Processing.
Mol Cell
; 73(3): 505-518.e5, 2019 02 07.
Article
em En
| MEDLINE
| ID: mdl-30554947
ABSTRACT
Microprocessor, composed of DROSHA and its cofactor DGCR8, initiates microRNA (miRNA) biogenesis by processing the primary transcripts of miRNA (pri-miRNAs). Here we investigate the mechanism by which Microprocessor selects the cleavage site with single-nucleotide precision, which is crucial for the specificity and functionality of miRNAs. By testing â¼40,000 pri-miRNA variants, we find that for some pri-miRNAs the cleavage site is dictated mainly by the mGHG motif embedded in the lower stem region of pri-miRNA. Structural modeling and deep-sequencing-based complementation experiments show that the double-stranded RNA-binding domain (dsRBD) of DROSHA recognizes mGHG to place the catalytic center in the appropriate position. The mGHG motif as well as the mGHG-recognizing residues in DROSHA dsRBD are conserved across eumetazoans, suggesting that this mechanism emerged in an early ancestor of the animal lineage. Our findings provide a basis for the understanding of miRNA biogenesis and rational design of accurate small-RNA-based gene silencing.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Processamento Pós-Transcricional do RNA
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MicroRNAs
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Ribonuclease III
/
Motivos de Nucleotídeos
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article