Coupling between snoRNP assembly and 3' processing controls box C/D snoRNA biosynthesis in yeast

EMBO J. 2004 Jun 16;23(12):2392-401. doi: 10.1038/sj.emboj.7600254. Epub 2004 May 27.


RNA polymerase II transcribes genes encoding proteins and a large number of small stable RNAs. While pre-mRNA 3'-end formation requires a machinery ensuring tight coupling between cleavage and polyadenylation, small RNAs utilize polyadenylation-independent pathways. In yeast, specific factors required for snRNA and snoRNA 3'-end formation were characterized as components of the APT complex that is associated with the core complex of the cleavage/polyadenylation machinery (core-CPF). Other essential factors were identified as independent components: Nrd1p, Nab3p and Sen1p. Here we report that mutations in the conserved box D of snoRNAs and in the snoRNP-specific factor Nop1p interfere with transcription and 3'-end formation of box C/D snoRNAs. We demonstrate that Nop1p is associated with box C/D snoRNA genes and that it interacts with APT components. These data suggest a mechanism of quality control in which efficient transcription and 3'-end formation occur only when nascent snoRNAs are successfully assembled into functional particles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA Primers
  • Mutation
  • Plasmids
  • Ribonucleoproteins, Small Nucleolar / metabolism*
  • Saccharomyces cerevisiae / metabolism*


  • DNA Primers
  • Ribonucleoproteins, Small Nucleolar