Molecular and General Genetics MGG

, Volume 262, Issue 3, pp 508–514

Mechanism of transcription termination: PTRF interacts with the largest subunit of RNA polymerase I and dissociates paused transcription complexes from yeast and mouse

Authors

  • P. Jansa
    • Division of Molecular Biology of the Cell II, German Cancer Research Center, D-69120 Heidelberg, Germany e-mail: cI.Grummt@DKFZ-Heidelberg.de Tel.: +49-6221-423 423; Fax: +49-6221-423 404
  • I. Grummt
    • Division of Molecular Biology of the Cell II, German Cancer Research Center, D-69120 Heidelberg, Germany e-mail: cI.Grummt@DKFZ-Heidelberg.de Tel.: +49-6221-423 423; Fax: +49-6221-423 404
ORIGINAL PAPER

DOI: 10.1007/s004380051112

Cite this article as:
Jansa, P. & Grummt, I. Mol Gen Genet (1999) 262: 508. doi:10.1007/s004380051112

Abstract

Transcription termination by RNA polymerase I (Pol I) is a stepwise process. First the elongating RNA polymerase is forced to pause by DNA-bound transcription termination factor (TTF-I). Then the ternary transcription complex is dissociated by PTRF, a novel factor that promotes release of both nascent transcripts and Pol I from the template. In this study we have investigated the ability of PTRF to liberate transcripts from ternary transcription complexes isolated from yeast and mouse. Using immobilized, tailed templates that contain terminator sequences from Saccharomyces cerevisiae and mouse, respectively, we demonstrate that PTRF promotes release of terminated transcripts, irrespective of whether mouse Pol I has interacted with the murine termination factor TTF-I or its yeast homolog Reb1p. In contrast, mouse Pol I paused by the lac repressor remains bound to the template both in the presence and absence of PTRF. We demonstrate that PTRF interacts with the largest subunit of murine Pol I, with TTF-I and Reb1p, but not the lac repressor. The results imply that Pol I transcription termination in yeast and mouse is mediated by conserved interactions between Pol I, Reb1p/TTF-I and PTRF.

Key words RNA polymerase ITranscription terminationTranscript releasePTRFYeast

Copyright information

© Springer-Verlag Berlin Heidelberg 1999