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PubMed · 9390555

The exosome: a conserved eukaryotic RNA processing complex containing multiple 3'-->5' exoribonucleases.

P Mitchell·E Petfalski·A Shevchenko·M Mann·D Tollervey
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Abstract

We identified a complex in S. cerevisiae, the "exosome," consisting of the five essential proteins Rrp4p, Rrp41p, Rrp42p, Rrp43p, and Rrp44p (Dis3p). Remarkably, four of these proteins are homologous to characterized bacterial 3'-->5' exoribonucleases; Rrp44p is homologous to RNase II, while Rrp41p, Rrp42p, and Rrp43p are related to RNase PH. Recombinant Rrp4p, Rrp44p, and Rrp41p are 3'-->5' exoribonucleases in vitro that have distributive, processive, and phosphorolytic activities, respectively. All components of the exosome are required for 3' processing of the 5.8S rRNA. Human Rrp4p is found in a comparably sized complex, and expression of the hRRP4 gene in yeast complements the rrp4-1 mutation. We conclude that the exosome constitutes a highly conserved eukaryotic RNA processing complex.

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Amino Acid SequenceExoribonucleasesFungal ProteinsGenetic Complementation TestHeLa CellsHumansMolecular Sequence DataMolecular WeightMultienzyme ComplexesMutationRNA Processing, Post-TranscriptionalRNA, Ribosomal, 5.8SRecombinant Fusion ProteinsSaccharomyces cerevisiaeSaccharomyces cerevisiae ProteinsJournal ArticleResearch Support, Non-U.S. Gov't

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P Mitchell, E Petfalski, A Shevchenko, M Mann, D Tollervey. 1997-11-14. The exosome: a conserved eukaryotic RNA processing complex containing multiple 3'-->5' exoribonucleases.. https://doi.org/10.1016/s0092-8674(00)80432-8

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