| Meiotic recombination increases genetic diversity and aids the proper segregation of homologous chromosomes through the formation of crossovers. Since improper crossing over can lead to non-disjunction and aneuploidy, the formation of crossovers is highly regulated and their distribution is non-random across the genome. My research has investigated the molecular mechanisms by which meiotic recombination occurs and the pathways involved in regulating this recombination. Through the course of my studies, I have used a combination of genetic, biochemical and evolutionary biological techniques to identify a novel complex of meiotic mini-chromosome maintenance proteins (mei-MCMs) that is essential for proper meiotic recombination in Drosophila melanogaster. I have found that this complex promotes crossover formation by antagonizing the anti-crossover protein BLM. In this manner, the mei-MCMs fill the functional niche of Msh4-Msh5, a protein complex that is absent in Drosophila but is necessary for interfering crossover formation in other organisms. In addition, I have discovered a role for the mei-MCMs in the regulation of crossover formation. In particular, I have shown that the mei-MCMs affect the number and distribution of crossovers. Collectively, these findings have provided insight into the pathways utilized in the regulation and formation of meiotic crossovers and have uncovered new avenues for future research in the meiotic recombination field. |
