Cryo-EM structures of the human Elongator complex at work.

ABSTRACT: tRNA modifications affect ribosomal elongation speed and co-translational folding dynamics. The Elongator complex is responsible for introducing 5-carboxymethyl at wobble uridine bases (cm⁵U₃₄) in eukaryotic tRNAs. However, the structure and function of human Elongator remain poorly understood. In this study, we present a series of cryo-EM structures of human ELP123 in complex with tRNA and cofactors at four different stages of the reaction. The structures at resolutions of up to 2.9 Å together with complementary functional analyses reveal the molecular mechanism of the modification reaction. Our results show that tRNA binding exposes a universally conserved uridine at position 33 (U₃₃), which triggers acetyl-CoA hydrolysis. We identify a series of conserve

SUBMITTER: Abbassi NE 

PROVIDER: S-EPMC11096365 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature