Mechanistic model of the Rrm3p helicase durin replication through non-nucleosomal protein complexes

• Antragstellerin: Professorin Dr. Katrin Paeschke
• Fachliche Zuordnung: Allgemeine Genetik und funktionelle Genomforschung
• Förderung: Förderung von 2007 bis 2009
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 50377307

DNA helicases are important to maintain genomic integrity during DNA replication, transcription, recombination and repair. The Saccharomyces cerevisiae helicase Rrm3p is required for normal replication fork progression through stable protein-DNA complexes. When replication proceeds in the absence of Rrm3p, replication forks stall and often break at over 1000 specific sites scattered throughout the genome. The goal of this research proposal is to understand the mechanism by which the DNA helicase Rrm3p promotes genomic stability, using both in vivo and in vitro approaches. First, I will test if the affinity of a protein complex for its binding site determines the extent of Rrm3p dependence during replication through that site. Replication through natural, low affinity and high affinity ORC-DNA binding complexes will be compared in the presence or absence of Rrm3p using neutral-neutral two dimensional gel electrophoresis. These studies will establish if forks pause more often or for longer periods of time at high affinity binding sites. Second, I will purify full length Rrm3p with the goal of determining its in vitro properties. In addition to standard helicase assays, I will test whether Rrm3p is able to remove specific protein-complexes from DNA. Since all eukaryotes face the problem of replicating through stable protein-DNA complexes in each S-phase, these studies are likely to be relevant to understanding genome integrity in diverse organisms.

• DFG-Verfahren: Forschungsstipendien
• Internationaler Bezug: USA
• Gastgeberin: Professorin Dr. Virginia Zakian