The pre-mRNA 5' cap determines whether U6 small nuclear RNA succeeds U1 small nuclear ribonucleoprotein particle at 5' splice sites.
Mol Cell Biol
; 18(12): 7510-20, 1998 Dec.
Article
em En
| MEDLINE
| ID: mdl-9819436
ABSTRACT
Efficient splicing of the 5'-most intron of pre-mRNA requires a 5' m7G(5')ppp(5')N cap, which has been implicated in U1 snRNP binding to 5' splice sites. We demonstrate that the cap alters the kinetic profile of U1 snRNP binding, but its major effect is on U6 snRNA binding. With two alternative wild-type splice sites in an adenovirus pre-mRNA, the cap selectively alters U1 snRNA binding at the site to which cap-independent U1 snRNP binding is stronger and that is used predominantly in splicing; with two consensus sites, the cap acts on both, even though one is substantially preferred for splicing. However, the most striking quantitative effect of the 5' cap is neither on U1 snRNP binding nor on the assembly of large complexes but on the replacement of U1 snRNP by U6 snRNA at the 5' splice site. Inhibition of splicing by a cap analogue is correlated with the loss of U6 interactions at the 5' splice site and not with any loss of U1 snRNP binding.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Capuzes de RNA
/
Precursores de RNA
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RNA Nuclear Pequeno
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Splicing de RNA
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Ribonucleoproteína Nuclear Pequena U1
Limite:
Humans
Idioma:
En
Ano de publicação:
1998
Tipo de documento:
Article