February 17, 2005
Title: Role of Mus81-Eme1 During Homologous Recombination in
Abstract: Homologous recombinaion is an important process in DNA metabolism during meiosis. It is required for accurate segregation of chromosomes, promotes DNA repair and generates genetic diversity (Wyman et al, 2004). Often, there are alterations that prevent recombination from oncoming. It is important that these obstacles can be overcome to maintain efficient DNA synthesis and with it, genome stability (Ahn et al, 2005). Genome instability can cause recombination between repetitive DNA elements, which then result in the expansion and contraction of tanlem arrays, or translocations between different chromosomes. These events can be hallmarks of some diseases such as Bloom’s Syndrome, Werner’s syndrome, Ataxia-telangiectasia and predisposition to cancer. Many of the models for homologous recombination during meiosis provide insights into the cleavage of Holliday junctions explaining crossing over. The endonuclease Mus81-Eme1 in fission yeast and humans is believed to cleave Holliday junctions, but leaves the physiological substrate undetermined. The findings here, suggest that crossing over, but not gene conversion is reduced in S. pombe Mus81-Eme1 mutants.