Charting DENR-dependent translation reinitiation uncovers predictive uORF features and links to circadian timekeeping via Clock.
Nucleic Acids Res
; 47(10): 5193-5209, 2019 06 04.
Article
em En
| MEDLINE
| ID: mdl-30982898
ABSTRACT
The non-canonical initiation factor DENR promotes translation reinitiation on mRNAs harbouring upstream open reading frames (uORFs). Moreover, DENR depletion shortens circadian period in mouse fibroblasts, suggesting involvement of uORF usage and reinitiation in clock regulation. To identify DENR-regulated translation events transcriptome-wide and, in particular, specific core clock transcripts affected by this mechanism, we have used ribosome profiling in DENR-deficient NIH3T3 cells. We uncovered 240 transcripts with altered translation rate, and used linear regression analysis to extract 5' UTR features predictive of DENR dependence. Among core clock genes, we identified Clock as a DENR target. Using Clock 5' UTR mutants, we mapped the specific uORF through which DENR acts to regulate CLOCK protein biosynthesis. Notably, these experiments revealed an alternative downstream start codon, likely representing the bona fide CLOCK N-terminus. Our findings provide insights into uORF-mediated translational regulation that can regulate the mammalian circadian clock and gene expression at large.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fases de Leitura Aberta
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Ritmo Circadiano
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Fatores de Iniciação em Eucariotos
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Proteínas CLOCK
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Fibroblastos
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article