Proteasomal ATPases are associated with rDNA: the ubiquitin proteasome system plays a direct role in RNA polymerase I transcription

Biochim Biophys Acta. 2008 Dec;1779(12):850-9. doi: 10.1016/j.bbagrm.2008.08.010. Epub 2008 Sep 6.


Significant amount of data have accumulated in the last several years pointing to the essential role of the ubiquitin proteasome system in the regulation of RNA polymerase II transcription; however, its involvement in RNA polymerase I transcription has remained largely unexplored. In this study, we demonstrate that proteasome activity is required for pre-rRNA synthesis. We can detect the association of proteasomal ATPases with both the rDNA promoter and coding region. Additionally, we show that the RNA polymerase I associated transcription factor, TIF-IA interacts with proteasomal ATPases, representing a potential link via which proteasomes and/or proteasome related complexes are recruited to rRNA genes. In summary, our findings suggest that the ubiquitin proteasome system is directly involved in RNA polymerase I transcription in analogy to the RNA polymerase II system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Adenosine Triphosphatases / physiology*
  • Animals
  • DNA, Ribosomal / metabolism*
  • Fluorescent Antibody Technique, Indirect
  • Humans
  • Mice
  • Models, Biological
  • Models, Genetic
  • NIH 3T3 Cells
  • Proteasome Endopeptidase Complex / metabolism*
  • RNA Polymerase I / metabolism*
  • RNA Polymerase II / metabolism
  • RNA, Ribosomal / metabolism
  • Transcription, Genetic*
  • Ubiquitin / chemistry*


  • DNA, Ribosomal
  • RNA, Ribosomal
  • RNA, ribosomal, 19S
  • Ubiquitin
  • RNA Polymerase II
  • RNA Polymerase I
  • Proteasome Endopeptidase Complex
  • Adenosine Triphosphatases