Chemical footprinting reveals conformational changes of 18S and 28S rRNAs at different steps of translation termination on the human ribosome.
RNA
; 22(2): 278-89, 2016 Feb.
Article
en En
| MEDLINE
| ID: mdl-26655225
Translation termination in eukaryotes is mediated by release factors: eRF1, which is responsible for stop codon recognition and peptidyl-tRNA hydrolysis, and GTPase eRF3, which stimulates peptide release. Here, we have utilized ribose-specific probes to investigate accessibility of rRNA backbone in complexes formed by association of mRNA- and tRNA-bound human ribosomes with eRF1â¢eRF3â¢GMPPNP, eRF1â¢eRF3â¢GTP, or eRF1 alone as compared with complexes where the A site is vacant or occupied by tRNA. Our data show which rRNA ribose moieties are protected from attack by the probes in the complexes with release factors and reveal the rRNA regions increasing their accessibility to the probes after the factors bind. These regions in 28S rRNA are helices 43 and 44 in the GTPase associated center, the apical loop of helix 71, and helices 89, 92, and 94 as well as 18S rRNA helices 18 and 34. Additionally, the obtained data suggest that eRF3 neither interacts with the rRNA ribose-phosphate backbone nor dissociates from the complex after GTP hydrolysis. Taken together, our findings provide new information on architecture of the eRF1 binding site on mammalian ribosome at various translation termination steps and on conformational rearrangements induced by binding of the release factors.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Terminación de la Cadena Péptídica Traduccional
/
ARN Mensajero
/
ARN Ribosómico 18S
/
ARN Ribosómico 28S
/
Aminoacil-ARN de Transferencia
/
Factores de Terminación de Péptidos
Límite:
Female
/
Humans
/
Pregnancy
Idioma:
En
Revista:
RNA
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2016
Tipo del documento:
Article
País de afiliación:
Rusia
Pais de publicación:
Estados Unidos