The nuclear exosome and adenylation regulate posttranscriptional tethering of yeast GAL genes to the nuclear periphery

Mol Cell. 2008 Jul 11;31(1):104-13. doi: 10.1016/j.molcel.2008.05.015.

Abstract

GAL genes and other activated yeast genes remain tethered to the nuclear periphery even after transcriptional shutoff. To identify factors that affect this tethering, we designed a plasmid-based visual screen. Although many factors affected GAL tethering during transcription, fewer specifically affected posttranscriptional tethering. Tw o of these, Rrp6p and Lrp1p, are nuclear exosome components known to contribute to RNA retention near transcription sites (dot RNA). Moreover, these exosome mutations lead to a substantial posttranscriptional increase in polyadenylated GAL1 3' ends. This accompanies a loss of unadenylated (pA-) GAL1 RNA and a loss of posttranscriptional gene-periphery tethering, as well as a decrease in dot RNA levels. This suggests that the exosome inhibits adenylation of some GAL1 transcripts, which results in the accumulation of pA- RNA adjacent to the GAL1 gene. We propose that this dot RNA, probably via RNP proteins, contributes to the physical tether linking the GAL1 gene to the nuclear periphery.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Biological Assay
  • Cell Nucleus / genetics*
  • Exoribonucleases
  • Exosome Multienzyme Ribonuclease Complex
  • Galactokinase / genetics*
  • Galactokinase / metabolism
  • Gene Expression Regulation, Fungal
  • Genes, Fungal*
  • Genes, Reporter
  • Green Fluorescent Proteins / metabolism
  • Molecular Sequence Data
  • Mutation / genetics
  • Plasmids / genetics
  • Poly A / metabolism
  • Polyadenylation / genetics*
  • RNA, Catalytic / metabolism
  • RNA, Fungal / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins / genetics*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Substrate Specificity
  • Transcription, Genetic*
  • Transcriptional Activation / genetics

Substances

  • RNA, Catalytic
  • RNA, Fungal
  • RNA, Messenger
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • Green Fluorescent Proteins
  • Poly A
  • GAL1 protein, S cerevisiae
  • Galactokinase
  • Exoribonucleases
  • Exosome Multienzyme Ribonuclease Complex
  • RRP6 protein, S cerevisiae