The Molecular Organization of Chromosome I: Control of Meiotic Recombination

The molecular mechanism of interference (the reduction of the rate of crossing over between some chromosomes) is not known. It has been suggested that the meiotic synaptonemal complex (SC) is involved in mediating interference. Therefore, a better understanding of the mechanism of interference might be gained by investigating the yeast S. cerevisiae SC. This project will examine the dynamics of SC formation in wild type and ndt80 mutant cells and identify the proteins and genes encoding these proteins. SC will be labeled using a functional, fluorescent ZIP1-GFP hybrid protein constructed in the principal investigator's laboratory. The structure and dynamics of fluorescent SC will be examined using optical sections and fluorescent cinema-microscopy. Fluorescent SC will be purified and proteins contained in these structures extracted and identified by tandem mass spectroscopy. Genes corresponding to each gene product will be identified and ultimately mutated so their role in SC formation, crossover interference and other aspects of meiotic recombination and pairing can be tested.