Complex of transfer-messenger RNA and elongation factor Tu. Unexpected modes of interaction.
J Biol Chem
; 276(50): 47702-8, 2001 Dec 14.
Article
en En
| MEDLINE
| ID: mdl-11595738
Transfer-messenger RNA (tmRNA) is a stable RNA in bacteria of 360 +/- 40 nucleotides that can be charged with alanine and can function as both tRNA and mRNA. Ribosomes that are stalled either in a coding region of mRNA or at the 3' end of an mRNA fragment lacking a stop codon are rescued by replacing their mRNA for tmRNA. Here we demonstrate that the interaction of tmRNA with the elongation factor Tu shows unexpected features. Deacylated tmRNA can form a complex with either EF-Tu.GDP or EF-Tu.GTP, the association constants are about one order of magnitude smaller than that of an Ala-tRNA.EF-Tu.GTP complex. tmRNA as well as Ala-tmRNA can be efficiently cross-linked with EF-Tu.GDP using a zero-length cross-link. The efficiency of cross-linking in the case of deacylated tmRNA does not depend on an intact CCA-3' end and is about the same, regardless whether protein mixtures such as the post-ribosomal supernatant (S100 enzymes) or purified EF-Tu are present. Two cross-linking sites with EF-Tu.GDP have been identified that are located outside the tRNA part of tmRNA, indicating an unusual interaction of tmRNA with EF-Tu.GDP.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ARN Mensajero
/
Factor Tu de Elongación Peptídica
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
J Biol Chem
Año:
2001
Tipo del documento:
Article
País de afiliación:
Rusia
Pais de publicación:
Estados Unidos