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Structures of the eukaryotic ribosome and its translational states in situ.

ABSTRACT: Ribosomes translate genetic information into primary structure. During translation, various cofactors transiently bind to the ribosome that undergoes prominent conformational and structural changes. Different translational states of ribosomes have been well characterized in vitro. However, to which extent the known translational states are representative of the native situation inside cells has thus far only been addressed in prokaryotes. Here, we apply cryo-electron tomography to cryo-FIB milled Dictyostelium discoideum cells combined with subtomogram averaging and classification. We obtain an in situ structure that is locally resolved up to 3 Angstrom, the distribution of eukaryotic ribosome translational states, and unique arrangement of rRNA expansion segments. Our work demonstrates the use of in situ structural biology techniques for identifying distinct ribosome states within the cellular environment.

SUBMITTER: Hoffmann PC

PROVIDER: S-EPMC9718845 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Structures of the eukaryotic ribosome and its translational states in situ.

Hoffmann Patrick C PC Kreysing Jan Philipp JP Khusainov Iskander I Tuijtel Maarten W MW Welsch Sonja S Beck Martin M

Nature communications 20221202 1

Ribosomes translate genetic information into primary structure. During translation, various cofactors transiently bind to the ribosome that undergoes prominent conformational and structural changes. Different translational states of ribosomes have been well characterized in vitro. However, to which extent the known translational states are representative of the native situation inside cells has thus far only been addressed in prokaryotes. Here, we apply cryo-electron tomography to cryo-FIB mille ...[more]

PMID: 36460643

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