Template disruptions and failure of double Holliday junction dissolution during double-strand break repair in Drosophila BLM mutants.

ABSTRACT: Previous biochemical studies of the BLM gene product have shown its ability in conjunction with topoisomerase IIIalpha to resolve double Holliday structures through a process called "dissolution." This process could prevent crossing over during repair of double-strand breaks. We report an analysis of the Drosophila BLM gene, DmBlm, in the repair of double-strand breaks in the premeiotic germ line of Drosophila males. With a repair reporter construct, Rr3, and other genetic tools, we show that DmBlm mutants are defective for homologous repair but show a compensating increase in single-strand annealing. Increases of 40- to 50-fold in crossing over and flanking deletions also were seen. Perhaps most significantly, the template used for homologous repair in DmBlm mutants is itself subject to d

SUBMITTER: Johnson-Schlitz D 

PROVIDER: S-EPMC1636541 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature