Structural insights into the evolution of late steps of translation initiation in the three domains of life

Ramy Kazan (1) , Gabrielle Bourgeois (1) , Christine Lazennec-Schurdevin (1) , Pierre-Damien Coureux (1) , Yves Mechulam (1) , Emmanuelle Schmitt (1)

1 BIOC - Laboratoire de Biologie Structurale de la Cellule

In eukaryotes and in archaea late steps of translation initiation involve the two initiation factors e/aIF5B and e/aIF1A. These two factors are also orthologous to the bacterial IF2 and IF1 proteins, respectively. Recent cryo-EM studies showed how e/aIF5B and e/aIF1A cooperate on the small ribosomal subunit to favor the binding of the large ribosomal subunit and the formation of a ribosome competent for elongation. In this review, pioneering studies and recent biochemical and structural results providing new insights into the role of a/eIF5B in archaea and eukaryotes will be presented. Recent structures will also be compared to orthologous bacterial initiation complexes to highlight domain-specific features and the evolution of initiation mechanisms.

Mots clés: Initiator tRNA; Late steps of initiation; Ribosome; eIF1A; eIF5B

Domaines: Biologie cellulaire; Biologie moléculaire

Ramy Kazan, Gabrielle Bourgeois, Christine Lazennec-Schurdevin, Pierre-Damien Coureux, Yves Mechulam, et al.. Structural insights into the evolution of late steps of translation initiation in the three domains of life. Biochimie, In press, pp.S0300-9084(23)00030-5. ⟨10.1016/j.biochi.2023.02.002⟩. ⟨hal-04058214⟩