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Structure of the mammalian ribosomal pre-termination complex associated with eRF1.eRF3.GDPNP.

ABSTRACT: Eukaryotic translation termination results from the complex functional interplay between two release factors, eRF1 and eRF3, in which GTP hydrolysis by eRF3 couples codon recognition with peptidyl-tRNA hydrolysis by eRF1. Here, we present a cryo-electron microscopy structure of pre-termination complexes associated with eRF1•eRF3•GDPNP at 9.7 -Å resolution, which corresponds to the initial pre-GTP hydrolysis stage of factor attachment and stop codon recognition. It reveals the ribosomal positions of eRFs and provides insights into the mechanisms of stop codon recognition and triggering of eRF3's GTPase activity.

SUBMITTER: des Georges A

PROVIDER: S-EPMC3950680 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Structure of the mammalian ribosomal pre-termination complex associated with eRF1.eRF3.GDPNP.

des Georges Amédée A Hashem Yaser Y Unbehaun Anett A Grassucci Robert A RA Taylor Derek D Hellen Christopher U T CU Pestova Tatyana V TV Frank Joachim J

Nucleic acids research 20131211 5

Eukaryotic translation termination results from the complex functional interplay between two release factors, eRF1 and eRF3, in which GTP hydrolysis by eRF3 couples codon recognition with peptidyl-tRNA hydrolysis by eRF1. Here, we present a cryo-electron microscopy structure of pre-termination complexes associated with eRF1•eRF3•GDPNP at 9.7 -Å resolution, which corresponds to the initial pre-GTP hydrolysis stage of factor attachment and stop codon recognition. It reveals the ribosomal positions ...[more]

PMID: 24335085

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