Small protein B interacts with the large and the small subunits of a stalled ribosome during trans-translation.

Abstract : During trans-translation, stalled bacterial ribosomes are rescued by small protein B (SmpB) and by transfer-messenger RNA (tmRNA). Stalled ribosomes switch translation from the defective messages to a short internal reading frame on tmRNA that tags the nascent peptide chain for degradation and recycles the ribosomes. We present evidences that SmpB binds the large and small ribosomal subunits in vivo and in vitro. The binding between SmpB and the ribosomal subunits is very tight, with a dissociation constant of 1.7 x 10(-10) M, similar to its K(D) for the 70S ribosome or for tmRNA. tmRNA displaces SmpB from its 50S binding but not from the 30S. In vivo, SmpB is detected on the 50S when trans-translation is impaired by lacking tmRNA or a functional SmpB. SmpB contacts the large subunit transiently and early during the trans-translational process. The affinity of SmpB for the two ribosomal subunits is modulated by tmRNA in the course of trans-translation. It is the first example of two copies of the same protein interacting with two different functional sites of the ribosomes.
Type de document :
Article dans une revue
Nucleic Acids Research, Oxford University Press, 2006, 34 (6), pp.1935-43. 〈10.1093/nar/gkl097〉
Liste complète des métadonnées

Littérature citée [25 références]  Voir  Masquer  Télécharger

http://www.hal.inserm.fr/inserm-00713111
Contributeur : Annick Lefevre <>
Soumis le : vendredi 29 juin 2012 - 13:06:23
Dernière modification le : mercredi 16 mai 2018 - 11:23:16
Document(s) archivé(s) le : dimanche 30 septembre 2012 - 02:25:32

Fichier

nar_2006.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Collections

Citation

Marc Hallier, Jessie Desreac, Brice Felden. Small protein B interacts with the large and the small subunits of a stalled ribosome during trans-translation.. Nucleic Acids Research, Oxford University Press, 2006, 34 (6), pp.1935-43. 〈10.1093/nar/gkl097〉. 〈inserm-00713111〉

Partager

Métriques

Consultations de la notice

119

Téléchargements de fichiers

131