9723360 Szauter Meiosis is a complex cellular process common to all sexually reproducing eukaryotes. The first division of meiosis has two unique features: recombination and the reductional segregation of homologous chromosomes. These processes are related, in that chiasmata are the result of recombination and are required for proper chromosome segregation. They are held together by a structure called the synaptonemal complex A mutation which eliminates recombination and synaptonemal complex assembly was found in Drosophila melanogaster and the chromosome region containing the mutation, c(3)G, was isolated. The gene will be localized within the cloned region and tested by complementation. When isolated, the gene will be sequenced. A working hypothesis, that c(3)G is a DNA repair gene, if confirmed will support the model which suggests that the formation of recombination intermediates is a prerequisite for synapsis in Drosophila. Despite extensive studies of meiosis in Drosophila, the underlying mechanism(s) involved is still not known. Drosophila has a life cycle more closely resembling those of other sexually reproducing multicellular eukaryotes than does yeast, (which is the other model organism for this process) and so information gained from this system may be more generally applicable to higher organisms.
