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RNA channelling by the eukaryotic exosome.

ABSTRACT: The eukaryotic exosome is a key nuclease for the degradation, processing and quality control of a wide variety of RNAs. Here, we report electron microscopic reconstructions and pseudo-atomic models of the ten-subunit Saccharomyces cerevisiae exosome in the unbound and RNA-bound states. In the RNA-bound structures, extra density that is visible at the entry and exit sites of the exosome channel indicates that a substrate-threading mechanism is used by the eukaryotic exosome. This channelling mechanism seems to be conserved in exosome-like complexes from all domains of life, and might have been present in the most recent common ancestor.

SUBMITTER: Malet H

PROVIDER: S-EPMC2999861 | biostudies-other | 2010 Dec

REPOSITORIES: biostudies-other

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RNA channelling by the eukaryotic exosome.

Malet Hélène H Topf Maya M Clare Daniel K DK Ebert Judith J Bonneau Fabien F Basquin Jerome J Drazkowska Karolina K Tomecki Rafal R Tomecki Rafal R Dziembowski Andrzej A Conti Elena E Saibil Helen R HR Lorentzen Esben E

EMBO reports 20101112 12

The eukaryotic exosome is a key nuclease for the degradation, processing and quality control of a wide variety of RNAs. Here, we report electron microscopic reconstructions and pseudo-atomic models of the ten-subunit Saccharomyces cerevisiae exosome in the unbound and RNA-bound states. In the RNA-bound structures, extra density that is visible at the entry and exit sites of the exosome channel indicates that a substrate-threading mechanism is used by the eukaryotic exosome. This channelling mech ...[more]

PMID: 21072061

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