The homologous chromosome is an effective template for the repair of mitotic DNA double-strand breaks in Drosophila.
In recombinational DNA double-strand break repair a homologous template for gene conversion may be located at several different genomic positions: on the homologous chromosome in diploid organisms, on the sister chromatid after DNA replication, or at an ectopic position. The use of the homologous chromosome in mitotic gene conversion is thought to be limited in the yeast Saccharomyces cerevisiae and mammalian cells. In contrast, by studying the repair of double-strand breaks generated by the I-SceI rare-cutting endonuclease, we find that the homologous chromosome is frequently used in Drosophila melanogaster, which we suggest is attributable to somatic pairing of homologous chromosomes in mitotic cells of Drosophila. We also find that Drosophila mitotic cells of the germ line, like yeast, employ the homologous recombinational repair pathway more often than imperfect nonhomologous end joining.
Rong
Yikang S
YS
Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA. rongy@mail.nih.gov
Golic
Kent G
KG
D000818:Animals; D030801:Animals, Genetically Modified; D002875:Chromosomes / Q000235:genetics*; D003433:Crosses, Genetic; D004247:DNA / Q000378:metabolism*; D004249:DNA Damage; D004260:DNA Repair; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D008297:Male; D008938:Mitosis; D011995:Recombination, Genetic; D029701:Saccharomyces cerevisiae Proteins; D015398:Signal Transduction; D013698:Templates, Genetic
D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; C037725:SCEI protein, S cerevisiae; D015252:Deoxyribonucleases, Type II Site-Specific