Local chromatin structure at the ribosomal DNA causes replication fork pausing and genome instability in the absence of the S. cerevisiae DNA helicase Rrm3p

  1. Jorge Z. Torres1,
  2. Jessica B. Bessler1, and
  3. Virginia A. Zakian2
  1. Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544-1014, USA

Abstract

Lack of the yeast Rrm3p DNA helicase causes replication defects at multiple sites within ribosomal DNA (rDNA), includingat the replication fork barrier (RFB). These defects were unaltered in rrm3 sir2 cells. When the RFB binding Fob1p was deleted, rrm3-generated defects at the RFB were eliminated, but defects at other rDNA sites were not affected. Thus, specific protein–DNA complexes make replication Rrm3p-dependent. Because rrm3-induced increases in recombination and cell cycle length were only partially suppressed in rrm3 fob1 cells, which still required checkpoint and fork restart activities for viability, non-RFB rrm3-induced defects contribute to rDNA fragility and genome instability.

Keywords

Footnotes

  • Article and publication are at http://www.genesdev.org/cgi/doi/10.1101/gad.1154704.

  • 1 These authors contributed equally to this work.

  • 2 Corresponding author.

    2 E-MAIL vzakian{at}molbio.princeton.edu; FAX (609) 258-1701.

    • Accepted February 3, 2004.
    • Received September 24, 2003.
| Table of Contents

Life Science Alliance