RNase Y is responsible for uncoupling the expression of translation factor IF3 from that of the ribosomal proteins L35 and L20 in Bacillus subtilis.
Mol Microbiol
; 81(6): 1526-41, 2011 Sep.
Article
em En
| MEDLINE
| ID: mdl-21843271
ABSTRACT
RNase Y is a novel endoribonuclease affecting global mRNA metabolism. We show that this nuclease affects the expression of the Bacillus subtilis infC-rpmI-rplT operon, encoding translation initiation factor IF3 and the ribosomal proteins L35 and L20. This operon is autoregulated by a complex L20-dependent transcription attenuation mechanism. L20 binds to a phylogenetically conserved domain on the 5' untranslated region of the infC mRNA which mimics the L20 binding sites on 23S rRNA. We have identified a second promoter (P1) upstream of the previously identified promoter (P2). The P1, but not the P2, readthrough transcript is stabilized in a strain depleted for RNase Y. However, under these conditions infC biosynthesis is repressed threefold. We show that the unprocessed P1 transcript is non-functional for IF3 translation but fully competent to express the co-transcribed ribosomal protein genes. RNase Y cleavage of the P1 transcript creates an entry site for the 5'-3' exonucleolytic activity of RNase J1 which degrades the infC mRNA when translation initiation efficiency is low. A second RNase Y cleavage is crucial for initiating degradation of the prematurely terminated infC leader RNAs, including the L20 operator complex, which permits efficient recycling of the L20 protein.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ribonucleases
/
Proteínas Ribossômicas
/
Bacillus subtilis
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Biossíntese de Proteínas
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Regulação Bacteriana da Expressão Gênica
/
Fator de Iniciação 3 em Procariotos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Mol Microbiol
Assunto da revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
França