Cryo-EM structure of the highly atypical cytoplasmic ribosome of Euglena gracilis.

ABSTRACT: Ribosomal RNA is the central component of the ribosome, mediating its functional and architectural properties. Here, we report the cryo-EM structure of a highly divergent cytoplasmic ribosome from the single-celled eukaryotic alga Euglena gracilis. The Euglena large ribosomal subunit is distinct in that it contains 14 discrete rRNA fragments that are assembled non-covalently into the canonical ribosome structure. The rRNA is substantially enriched in post-transcriptional modifications that are spread far beyond the catalytic RNA core, contributing to the stabilization of this highly fragmented ribosome species. A unique cluster of five adenosine base methylations is found in an expansion segment adjacent to the protein exit tunnel, such that it is positioned for interaction with the nascen

SUBMITTER: Matzov D 

PROVIDER: S-EPMC7672448 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature