Browse by author
Lookup NU author(s): Dr Claudia SchneiderORCiD, Eileen Leung, Dr Jeremy Brown
Nuclear and cytoplasmic forms of the yeast exosome share 10 components, of which only Rrp44/Dis3 is believed to possess 3' exonuclease activity. We report that expression only of Rrp44 lacking 3'-exonuclease activity (Rrp44-exo) supports growth in S288c-related strains (BY4741). In BY4741, rrp44-exo was synthetic-lethal with loss of the cytoplasmic 5'-exonuclease Xrn1, indicating block of mRNA turnover, but not with loss of the nuclear 3'-exonuclease Rrp6. The RNA processing phenotype of rrp44-exo was milder than that seen on Rrp44 depletion, indicating that Rrp44-exo retains important functions. Recombinant Rrp44 was shown to possess manganese-dependent endonuclease activity in vitro that was abolished by four point mutations in the putative metal binding residues of its N-terminal PIN domain. Rrp44 lacking both exonuclease and endonuclease activity failed to support growth in strains depleted of endogenous Rrp44. Strains expressing Rrp44-exo and Rrp44-endo-exo exhibited different RNA processing patterns in vivo suggesting Rrp44-dependent endonucleolytic cleavages in the 5'-ETS and ITS2 regions of the pre-rRNA. Finally, the N-terminal PIN domain was shown to be necessary and sufficient for association with the core exosome, indicating its dual function as a nuclease and structural element.
Author(s): Schneider C, Leung E, Brown J, Tollervey D
Publication type: Article
Publication status: Published
Journal: Nucleic Acids Research
Year: 2009
Volume: 37
Issue: 4
Pages: 1127-1140
Date deposited: 06/04/2010
ISSN (print): 0305-1048
ISSN (electronic): 1362-4962
Publisher: Oxford University Press
URL: http://dx.doi.org/10.1093/nar/gkn1020
DOI: 10.1093/nar/gkn1020
PubMed id: 19129231
Notes: Biotechnology and Biological Sciences Research Council/United Kingdom Wellcome Trust/United Kingdom Research Support, Non-U.S. Gov't England
Altmetrics provided by Altmetric