The Replication Fork Barrier Site Forms a Unique Structure with Fob1p and Inhibits the Replication Fork
- 1 December 2003
- journal article
- research article
- Published by Taylor & Francis in Molecular and Cellular Biology
- Vol. 23 (24), 9178-9188
- https://doi.org/10.1128/mcb.23.24.9178-9188.2003
Abstract
The replication fork barrier site (RFB) is an ∼100-bp DNA sequence located near the 3′ end of the rRNA genes in the yeast Saccharomyces cerevisiae. The gene FOB1 is required for this RFB activity. FOB1 is also necessary for recombination in the ribosomal DNA (rDNA), including increase and decrease of rDNA repeat copy number, production of extrachromosomal rDNA circles, and possibly homogenization of the repeats. Despite the central role that Foblp plays in both replication fork blocking and rDNA recombination, the molecular mechanism by which Fob1p mediates these activities has not been determined. Here, I show by using chromatin immunoprecipitation, gel shift, footprinting, and atomic force microscopy assays that Fob1p directly binds to the RFB. Fob1p binds to two separated sequences in the RFB. A predicted zinc finger motif in Fob1p was shown to be essential for the RFB binding, replication fork blocking, and rDNA recombination activities. The RFB seems to wrap around Fob1p, and this wrapping structure may be important for function in the rDNA repeats.Keywords
This publication has 53 references indexed in Scilit:
- Transcription-dependent recombination and the role of fork collision in yeast rDNAGenes & Development, 2003
- In Exponentially Growing Saccharomyces cerevisiae Cells, rRNA Synthesis Is Determined by the Summed RNA Polymerase I Loading Rate Rather than by the Number of Active GenesMolecular and Cellular Biology, 2003
- A model of the replication fork blocking protein Fob1p based on the catalytic core domain of retroviral integrasesProtein Science, 2002
- hpr1Δ Affects Ribosomal DNA Recombination and Cell Life Span in Saccharomyces cerevisiaeMolecular and Cellular Biology, 2002
- Yeast RNA Polymerase I Enhancer Is Dispensable for Transcription of the Chromosomal rRNA Gene and Cell Growth, and Its Apparent Transcription Enhancement from Ectopic Promoters Requires Fob1 ProteinMolecular and Cellular Biology, 2001
- A yeast gene product, Fob1 protein, required for both replication fork blocking and recombinational hotspot activitiesGenes to Cells, 1996
- The arrest of replication forks in the rDNA of yeast occurs independently of transcriptionCell, 1992
- New yeast-Escherichia coli shuttle vectors constructed with in vitro mutagenized yeast genes lacking six-base pair restriction sitesGene, 1988
- The major promoter element of rRNA transcription in yeast lies 2 kb upstreamCell, 1984
- The 5′ ends of Drosophila heat shock genes in chromatin are hypersensitive to DNase INature, 1980