A single subunit, Dis3, is essentially responsible for yeast exosome core activity

Andrzej Dziembowski; Esben Lorentzen; Elena Conti; Bertrand Séraphin

doi:10.1038/nsmb1184

A single subunit, Dis3, is essentially responsible for yeast exosome core activity

Nat Struct Mol Biol. 2007 Jan;14(1):15-22. doi: 10.1038/nsmb1184. Epub 2006 Dec 17.

Authors

Andrzej Dziembowski¹, Esben Lorentzen, Elena Conti, Bertrand Séraphin

Affiliation

¹ Equipe labellisée La Ligue, Centre de Genetique Moleculaire, Centre National de la Recherche Scientifique UPR2167, associée à l'Université Pierre et Marie Curie, Avenue de la Terrasse, 91198 Gif sur Yvette Cedex, France. andrzejd@ibb.waw.pl

PMID: 17173052
DOI: 10.1038/nsmb1184

Abstract

The conserved core of the exosome, the major eukaryotic 3' --> 5' exonuclease, contains nine subunits that form a ring similar to the phosphorolytic bacterial PNPase and archaeal exosome, as well as Dis3. Dis3 is homologous to bacterial RNase II, a hydrolytic enzyme. Previous studies have suggested that all subunits are active 3' --> 5' exoRNases. We show here that Dis3 is responsible for exosome core activity. The purified exosome core has a hydrolytic, processive and Mg(2+)-dependent activity with characteristics similar to those of recombinant Dis3. Moreover, a catalytically inactive Dis3 mutant has no exosome core activity in vitro and shows in vivo RNA degradation phenotypes similar to those resulting from exosome depletion. In contrast, mutations in Rrp41, the only subunit carrying a conserved phosphorolytic site, appear phenotypically not different from wild-type yeast. We observed that the yeast exosome ring mediates interactions with protein partners, providing an explanation for its essential function.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adaptor Proteins, Signal Transducing
Exoribonucleases / chemistry*
Exoribonucleases / genetics
Exoribonucleases / metabolism*
Exosome Multienzyme Ribonuclease Complex
Fungal Proteins / genetics
Fungal Proteins / metabolism*
Magnesium Chloride / metabolism
Multienzyme Complexes / metabolism
Mutation
RNA Stability*
RNA, Messenger / metabolism
RNA, Ribosomal / metabolism
RNA, Ribosomal, 5.8S / metabolism
Saccharomyces cerevisiae / chemistry*
Saccharomyces cerevisiae / genetics
Saccharomyces cerevisiae / metabolism
Saccharomyces cerevisiae Proteins / genetics
Saccharomyces cerevisiae Proteins / metabolism

Substances

Adaptor Proteins, Signal Transducing
Fungal Proteins
Multienzyme Complexes
RNA, Messenger
RNA, Ribosomal
RNA, Ribosomal, 5.8S
SKI6 protein, S cerevisiae
SKI7 protein, S cerevisiae
Saccharomyces cerevisiae Proteins
Magnesium Chloride
Exoribonucleases
Exosome Multienzyme Ribonuclease Complex
DIS3 protein, S cerevisiae
RRP6 protein, S cerevisiae