Turnover of aberrant pre-40S pre-ribosomal particles is initiated by a novel endonucleolytic decay pathway.
Nucleic Acids Res
; 46(9): 4699-4714, 2018 05 18.
Article
em En
| MEDLINE
| ID: mdl-29481617
Ribosome biogenesis requires more than 200 trans-acting factors to achieve the correct production of the two mature ribosomal subunits. Here, we have identified Efg1 as a novel, nucleolar ribosome biogenesis factor in Saccharomyces cerevisiae that is directly linked to the surveillance of pre-40S particles. Depletion of Efg1 impairs early pre-rRNA processing, leading to a strong decrease in 18S rRNA and 40S subunit levels and an accumulation of the aberrant 23S rRNA. Using Efg1 as bait, we revealed a novel degradation pathway of the 23S rRNA. Co-immunoprecipitation experiments showed that Efg1 is a component of 90S pre-ribosomes, as it is associated with the 35S pre-rRNA and U3 snoRNA, but has stronger affinity for 23S pre-rRNA and its novel degradation intermediate 11S rRNA. 23S is cleaved at a new site, Q1, within the 18S sequence by the endonuclease Utp24, generating 11S and 17S' rRNA. Both of these cleavage products are targeted for degradation by the TRAMP/exosome complexes. Therefore, the Q1 site defines a novel endonucleolytic cleavage site of ribosomal RNA exclusively dedicated to surveillance of pre-ribosomal particles.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Nucleares
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RNA Ribossômico 23S
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Processamento Pós-Transcricional do RNA
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Proteínas de Saccharomyces cerevisiae
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Subunidades Ribossômicas Menores de Eucariotos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
França
País de publicação:
Reino Unido