Auxiliary downstream elements are required for efficient polyadenylation of mammalian pre-mRNAs.
Nucleic Acids Res
; 26(12): 2891-8, 1998 Jun 15.
Article
em En
| MEDLINE
| ID: mdl-9611233
ABSTRACT
We have previously identified a G-rich sequence (GRS) as an auxiliary downstream element (AUX DSE) which influences the processing efficiency of the SV40 late polyadenylation signal. We have now determined that sequences downstream of the core U-rich element (URE) form a fundamental part of mammalian polyadenylation signals. These novel AUX DSEs all influenced the efficiency of 3'-end processing in vitro by stabilizing the assembly of CstF on the core downstream URE. Three possible mechanisms by which AUX DSEs mediate efficient in vitro 3'-end processing have been explored. First, AUX DSEs can promote processing efficiency by maintaining the core elements in an unstructured domain which allows the general polyadenylation factors to efficiently assemble on the RNA substrate. Second, AUX DSEs can enhance processing by forming a stable structure which helps focus binding of CstF to the core downstream URE. Finally, the GRS element, but not the binding site for the bacteriophage R17 coat protein, can substitute for the auxiliary downstream region of the adenovirus L3 polyadenylation signal. This suggests that AUX DSE binding proteins may play an active role in stimulating 3'-end processing by stabilizing the association of CstF with the RNA substrate. AUX DSEs, therefore, serve as a integral part of the polyadenylation signal and can affect signal strength and possibly regulation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
RNA Mensageiro
/
Precursores de RNA
/
Sequências Reguladoras de Ácido Nucleico
/
Processamento Pós-Transcricional do RNA
/
Proteínas de Ligação a RNA
/
Proteínas do Capsídeo
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Estados Unidos