A conformational switch in PRP8 mediates metal ion coordination that promotes pre-mRNA exon ligation.
Nat Struct Mol Biol
; 20(6): 728-34, 2013 Jun.
Article
em En
| MEDLINE
| ID: mdl-23686287
ABSTRACT
Splicing of pre-mRNAs in eukaryotes is catalyzed by the spliceosome, a large RNA-protein metalloenzyme. The catalytic center of the spliceosome involves a structure comprising the U2 and U6 snRNAs and includes a metal bound by U6 snRNA. The precise architecture of the splicesome active site, however, and the question of whether it includes protein components, remains unresolved. A wealth of evidence places the protein PRP8 at the heart of the spliceosome through assembly and catalysis. Here we provide evidence that the RNase H domain of PRP8 undergoes a conformational switch between the two steps of splicing, rationalizing yeast prp8 alleles that promote either the first or second step. We also show that this switch unmasks a metal-binding site involved in the second step. Together, these data establish that PRP8 is a metalloprotein that promotes exon ligation within the spliceosome.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
/
Precursores de RNA
/
Ribonucleoproteína Nuclear Pequena U5
/
Ribonucleoproteína Nuclear Pequena U4-U6
/
Proteínas de Saccharomyces cerevisiae
/
Íons
/
Metais
Idioma:
En
Revista:
Nat Struct Mol Biol
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Canadá