Termination of pre-mRNA splicing requires that the ATPase and RNA unwindase Prp43p acts on the catalytic snRNA U6.
Genes Dev
; 33(21-22): 1555-1574, 2019 11 01.
Article
em En
| MEDLINE
| ID: mdl-31558568
ABSTRACT
The termination of pre-mRNA splicing functions to discard suboptimal substrates, thereby enhancing fidelity, and to release excised introns in a manner coupled to spliceosome disassembly, thereby allowing recycling. The mechanism of termination, including the RNA target of the DEAH-box ATPase Prp43p, remains ambiguous. We discovered a critical role for nucleotides at the 3' end of the catalytic U6 small nuclear RNA in splicing termination. Although conserved sequence at the 3' end is not required, 2' hydroxyls are, paralleling requirements for Prp43p biochemical activities. Although the 3' end of U6 is not required for recruiting Prp43p to the spliceosome, the 3' end cross-links directly to Prp43p in an RNA-dependent manner. Our data indicate a mechanism of splicing termination in which Prp43p translocates along U6 from the 3' end to disassemble the spliceosome and thereby release suboptimal substrates or excised introns. This mechanism reveals that the spliceosome becomes primed for termination at the same stage it becomes activated for catalysis, implying a requirement for stringent control of spliceosome activity within the cell.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA Nuclear Pequeno
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Splicing de RNA
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Spliceossomos
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Adenosina Trifosfatases
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Proteínas de Saccharomyces cerevisiae
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RNA Helicases DEAD-box
Idioma:
En
Revista:
Genes Dev
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos