Cryo-EM structure of the hibernating Thermus thermophilus 100S ribosome reveals a protein-mediated dimerization mechanism.
Fiche publication
Date publication
octobre 2018
Journal
Nature communications
Auteurs
Membres identifiés du Cancéropôle Est :
Dr YUSUPOV Marat
Tous les auteurs :
Flygaard RK, Boegholm N, Yusupov M, Jenner LB
Lien Pubmed
Résumé
In response to cellular stresses bacteria conserve energy by dimerization of ribosomes into inactive hibernating 100S ribosome particles. Ribosome dimerization in Thermus thermophilus is facilitated by hibernation-promoting factor (TtHPF). In this study we demonstrate high sensitivity of Tt100S formation to the levels of TtHPF and show that a 1:1 ratio leads to optimal dimerization. We report structures of the T. thermophilus 100S ribosome determined by cryo-electron microscopy to average resolutions of 4.13 Å and 4.57 Å. In addition, we present a 3.28 Å high-resolution cryo-EM reconstruction of a 70S ribosome from a hibernating ribosome dimer and reveal a role for the linker region connecting the TtHPF N- and C-terminal domains in translation inhibition by preventing Shine-Dalgarno duplex formation. Our work demonstrates that species-specific differences in the dimerization interface govern the overall conformation of the 100S ribosome particle and that for Thermus thermophilus no ribosome-ribosome interactions are involved in the interface.
Mots clés
Bacterial Proteins, metabolism, Cryoelectron Microscopy, DNA-Directed RNA Polymerases, metabolism, Dimerization, Models, Molecular, Protein Domains, Protein Subunits, chemistry, Ribosomes, metabolism, Thermus thermophilus, metabolism
Référence
Nat Commun. 2018 Oct 9;9(1):4179