Positioning of CCA-arms of the A- and the P-tRNAs towards the 28S rRNA in the human ribosome.
Biochimie
; 95(2): 195-203, 2013 Feb.
Article
en En
| MEDLINE
| ID: mdl-23023194
Nucleotides of 28S rRNA involved in binding of the human 80S ribosome with acceptor ends of the A site and the P site tRNAs were determined using two complementary approaches, namely, cross-linking with application of tRNA(Asp) analogues substituted with 4-thiouridine in position 75 or 76 and hydroxyl radical footprinting with the use of the full sized tRNA and the tRNA deprived of the 3'-terminal trinucleotide CCA. In general, these 28S rRNA nucleotides are located in ribosomal regions homologous to the A, P and E sites of the prokaryotic 50S subunit. However, none of the approaches used discovered interactions of the apex of the large rRNA helix 80 with the acceptor end of the P site tRNA typical with prokaryotic ribosomes. Application of the results obtained to available atomic models of 50S and 60S subunits led us to a conclusion that the A site tRNA is actually present in both A/A and A/P states and the P site tRNA in the P/P and P/E states. Thus, the present study gives a biochemical confirmation of the data on the structure and dynamics of the mammalian ribosomal pretranslocation complex obtained with application of cryo-electron microscopy and single-molecule FRET [Budkevich et al., 2011]. Moreover, in our study, particular sets of 28S rRNA nucleotides involved in oscillations of tRNAs CCA-termini between their alternative locations in the mammalian 80S ribosome are revealed.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ribosomas
/
Tiouridina
/
Biosíntesis de Proteínas
/
ARN de Transferencia de Aspártico
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Biochimie
Año:
2013
Tipo del documento:
Article
País de afiliación:
Rusia
Pais de publicación:
Francia