Cryo-EM study of an archaeal 30S initiation complex gives insights into evolution of translation initiation - École polytechnique Accéder directement au contenu
Article Dans Une Revue Communications Biology Année : 2020

Cryo-EM study of an archaeal 30S initiation complex gives insights into evolution of translation initiation

Résumé

Archaeal translation initiation occurs within a macromolecular complex containing the small ribosomal subunit (30S) bound to mRNA, initiation factors aIF1, aIF1A and the ternary complex aIF2:GDPNP:Met-tRNAiMet. Here, we determine the cryo-EM structure of a 30S:mRNA:aIF1A:aIF2:GTP:Met-tRNAiMet complex from Pyrococcus abyssi at 3.2 Å resolution. It highlights archaeal features in ribosomal proteins and rRNA modifications. We find an aS21 protein, at the location of eS21 in eukaryotic ribosomes. Moreover, we identify an N-terminal extension of archaeal eL41 contacting the P site. We characterize 34 N4-acetylcytidines distributed throughout 16S rRNA, likely contributing to hyperthermostability. Without aIF1, the 30S head is stabilized and initiator tRNA is tightly bound to the P site. A network of interactions involving tRNA, mRNA, rRNA modified nucleotides and C-terminal tails of uS9, uS13 and uS19 is observed. Universal features and domain-specific idiosyncrasies of translation initiation are discussed in light of ribosomal structures from representatives of each domain of life.
Fichier principal
Vignette du fichier
s42003-020-0780-0(1).pdf (2.1 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-02493692 , version 1 (27-11-2020)

Identifiants

Citer

Pierre-Damien Coureux, Christine Lazennec-Schurdevin, Sophie Bourcier, Yves Mechulam, Emmanuelle Schmitt. Cryo-EM study of an archaeal 30S initiation complex gives insights into evolution of translation initiation. Communications Biology, 2020, 3 (1), ⟨10.1038/s42003-020-0780-0⟩. ⟨hal-02493692⟩
265 Consultations
73 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More