"Identification of yeast genes important for chromosome transmission"

Accurate transmission of chromosomes during cell division requires that chromosomes are fully replicated and free of damage prior to cell division. Furthermore, cellular processes that separate chromosomes must be functional. As part of an effort to identify proteins important for chromosome transmission, we implemented a genetic screen in the yeast Saccharomyces ceresisiae that allows for visual detection of mutants with an increase in the loss of an ADE2-marked yeast artificial chromosome (YAC). This screen resulted in 132 YAC stability in mitosis (ysm) mutants. In addition to genetic characterization of these mutants, subsets of the ysm's were analyzed for YAC loss rate, sporulation efficiency, forward mutation frequency, and cell morphology. Mutants were also tested for sensitivity to high salt, caffeine, hydroxyurea, and benomyl. The results elucidated mutant phenotypes that will facilitate cloning the wild-type genes that are altered in these mutants. To this end, high copy suppressors of ysm83 and ysm84 have recently been isolated.Drake University, College of Arts and Sciences, Department of Biology