Structural basis for processivity and single-strand specificity of RNase II.
Mol Cell
; 24(1): 149-56, 2006 Oct 06.
Article
em En
| MEDLINE
| ID: mdl-16996291
ABSTRACT
RNase II is a member of the widely distributed RNR family of exoribonucleases, which are highly processive 3'-->5' hydrolytic enzymes that play an important role in mRNA decay. Here, we report the crystal structure of E. coli RNase II, which reveals an architecture reminiscent of the RNA exosome. Three RNA-binding domains come together to form a clamp-like assembly, which can only accommodate single-stranded RNA. This leads into a narrow, basic channel that ends at the putative catalytic center that is completely enclosed within the body of the protein. The putative path for RNA agrees well with biochemical data indicating that a 3' single strand overhang of 7-10 nt is necessary for binding and hydrolysis by RNase II. The presence of the clamp and the narrow channel provides an explanation for the processivity of RNase II and for why its action is limited to single-stranded RNA.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA Mensageiro
/
Escherichia coli
/
Exorribonucleases
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Estados Unidos