Abstract
Ribosome-driven protein biosynthesis is comprised of four phases: initiation, elongation, termination and recycling. In bacteria, ribosome recycling requires ribosome recycling factor and elongation factor G, and several structures of bacterial recycling complexes have been determined. In the eukaryotic and archaeal kingdoms, however, recycling involves the ABC-type ATPase ABCE1 and little is known about its structural basis. Here we present cryo-electron microscopy reconstructions of eukaryotic and archaeal ribosome recycling complexes containing ABCE1 and the termination factor paralogue Pelota. These structures reveal the overall binding mode of ABCE1 to be similar to canonical translation factors. Moreover, the iron-sulphur cluster domain of ABCE1 interacts with and stabilizes Pelota in a conformation that reaches towards the peptidyl transferase centre, thus explaining how ABCE1 may stimulate peptide-release activity of canonical termination factors. Using the mechanochemical properties of ABCE1, a conserved mechanism in archaea and eukaryotes is suggested that couples translation termination to recycling, and eventually to re-initiation.
Publication types
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Research Support, N.I.H., Extramural
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Research Support, Non-U.S. Gov't
MeSH terms
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ATP-Binding Cassette Transporters / chemistry
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ATP-Binding Cassette Transporters / metabolism
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Cell Cycle Proteins / chemistry
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Cell Cycle Proteins / metabolism
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Cryoelectron Microscopy
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Endoribonucleases / chemistry
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Endoribonucleases / metabolism
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Evolution, Molecular*
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Iron-Sulfur Proteins / chemistry
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Iron-Sulfur Proteins / metabolism
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Models, Molecular
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Movement
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Multiprotein Complexes / chemistry
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Multiprotein Complexes / metabolism
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Nuclear Proteins / chemistry
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Nuclear Proteins / metabolism
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Peptide Termination Factors / chemistry
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Peptide Termination Factors / metabolism
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Protein Binding
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Protein Stability
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Protein Structure, Tertiary
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Pyrococcus furiosus / chemistry*
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Pyrococcus furiosus / metabolism
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Ribosomes / chemistry*
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Ribosomes / metabolism*
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Ribosomes / ultrastructure
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Saccharomyces cerevisiae / chemistry*
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Saccharomyces cerevisiae / metabolism
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Saccharomyces cerevisiae Proteins / chemistry
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Saccharomyces cerevisiae Proteins / metabolism
Substances
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ATP-Binding Cassette Transporters
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Cell Cycle Proteins
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Iron-Sulfur Proteins
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Multiprotein Complexes
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Nuclear Proteins
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Peptide Termination Factors
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RLI1 protein, S cerevisiae
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Saccharomyces cerevisiae Proteins
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Dom34 protein, S cerevisiae
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Endoribonucleases