Mammalian 5'-capped microRNA precursors that generate a single microRNA.
Cell
; 155(7): 1568-80, 2013 Dec 19.
Article
em En
| MEDLINE
| ID: mdl-24360278
ABSTRACT
MicroRNAs (miRNAs) are short RNA gene regulators typically produced from primary transcripts that are cleaved by the nuclear microprocessor complex, with the resulting precursor miRNA hairpins exported by exportin 5 and processed by cytoplasmic Dicer to yield two (5p and 3p) miRNAs. Here, we document microprocessor-independent 7-methylguanosine (m(7)G)-capped pre-miRNAs, whose 5' ends coincide with transcription start sites and 3' ends are most likely generated by transcription termination. By establishing a small RNA Cap-seq method that employs the cap-binding protein eIF4E, we identified a group of murine m(7)G-capped pre-miRNAs genome wide. The m(7)G-capped pre-miRNAs are exported via the PHAX-exportin 1 pathway. After Dicer cleavage, only the 3p-miRNA is efficiently loaded onto Argonaute to form a functional microRNP. This unusual miRNA biogenesis pathway, which differs in pre-miRNA synthesis, nuclear-cytoplasmic transport, and guide strand selection, enables the development of shRNA expression constructs that produce a single 3p-siRNA.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Capuzes de RNA
/
MicroRNAs
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article