Structural basis for the transition from translation initiation to elongation by an 80S-eIF5B complex.
Nat Commun
; 11(1): 5003, 2020 10 06.
Article
in En
| MEDLINE
| ID: mdl-33024099
ABSTRACT
Recognition of a start codon by the initiator aminoacyl-tRNA determines the reading frame of messenger RNA (mRNA) translation by the ribosome. In eukaryotes, the GTPase eIF5B collaborates in the correct positioning of the initiator Met-tRNAiMet on the ribosome in the later stages of translation initiation, gating entrance into elongation. Leveraging the long residence time of eIF5B on the ribosome recently identified by single-molecule fluorescence measurements, we determine the cryoEM structure of the naturally long-lived ribosome complex with eIF5B and Met-tRNAiMet immediately before transition into elongation. The structure uncovers an unexpected, eukaryotic specific and dynamic fidelity checkpoint implemented by eIF5B in concert with components of the large ribosomal subunit.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Peptide Chain Elongation, Translational
/
Peptide Chain Initiation, Translational
/
Eukaryotic Initiation Factors
/
Ribosome Subunits, Large
Type of study:
Prognostic_studies
Language:
En
Journal:
Nat Commun
Journal subject:
BIOLOGIA
/
CIENCIA
Year:
2020
Document type:
Article
Affiliation country:
United States