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Cryo-EM structure of the mammalian eukaryotic release factor eRF1-eRF3-associated termination complex.

ABSTRACT: Eukaryotic translation termination results from the complex functional interplay between two eukaryotic release factors, eRF1 and eRF3, and the ribosome, in which GTP hydrolysis by eRF3 couples codon recognition with peptidyl-tRNA hydrolysis by eRF1. Here, using cryo-electron microscopy (cryo-EM) and flexible fitting, we determined the structure of eRF1-eRF3-guanosine 5'-[?,?-imido]triphosphate (GMPPNP)-bound ribosomal pretermination complex (pre-TC), which corresponds to the initial, pre-GTP hydrolysis stage of factor attachment. Our results show that eukaryotic translation termination involves a network of interactions between the two release factors and the ribosome. Our structure provides mechanistic insight into the coordination between GTP hydrolysis by eRF3 and subsequent peptide release by eRF1.

SUBMITTER: Taylor D

PROVIDER: S-EPMC3494903 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Cryo-EM structure of the mammalian eukaryotic release factor eRF1-eRF3-associated termination complex.

Taylor Derek D Unbehaun Anett A Li Wen W Das Sanchaita S Lei Jianlin J Liao Hstau Y HY Grassucci Robert A RA Pestova Tatyana V TV Frank Joachim J

Proceedings of the National Academy of Sciences of the United States of America 20121022 45

Eukaryotic translation termination results from the complex functional interplay between two eukaryotic release factors, eRF1 and eRF3, and the ribosome, in which GTP hydrolysis by eRF3 couples codon recognition with peptidyl-tRNA hydrolysis by eRF1. Here, using cryo-electron microscopy (cryo-EM) and flexible fitting, we determined the structure of eRF1-eRF3-guanosine 5'-[β,γ-imido]triphosphate (GMPPNP)-bound ribosomal pretermination complex (pre-TC), which corresponds to the initial, pre-GTP hy ...[more]

PMID: 23091004

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Distinct eRF3 requirements suggest alternate eRF1 conformations mediate peptide release during eukaryotic translation termination.

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Cryo-EM visualization of the ribosome in termination complex with apo-RF3 and RF1.

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