, Volume 49, Issue 3, pp 447-456,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 16 Jun 2010

Saccharomyces cerevisiae-based system for studying clustered DNA damages

Abstract

DNA-damaging agents can induce clustered lesions or multiply damaged sites (MDSs) on the same or opposing DNA strands. In the latter, attempts to repair MDS can generate closely opposed single-strand break intermediates that may convert non-lethal or mutagenic base damage into double-strand breaks (DSBs). We constructed a diploid S. cerevisiae yeast strain with a chromosomal context targeted by integrative DNA fragments carrying different damages to determine whether closely opposed base damages are converted to DSBs following the outcomes of the homologous recombination repair pathway. As a model of MDS, we studied clustered uracil DNA damages with a known location and a defined distance separating the lesions. The system we describe might well be extended to assessing the repair of MDSs with different compositions, and to most of the complex DNA lesions induced by physical and chemical agents.

This manuscript is based on a contribution given at the “Heavy Ions in Therapy and Space Symposium 2009,” July 6–10, 2009, Cologne, Germany.
A week before the submission of this article, Betsy Sutherland passed away. The Biology Department of Brookhaven National Laboratory and the worldwide community of scientists who are focused on DNA damage and repair have lost a friend and a colleague, a critical discussion partner, and an innovative thinker. Her loss leaves a void that it will take a while to fill.