ISOLATION AND CHARACTERIZATION OF NEOMYCIN-SENSITIVE MUTANTS IN SACCHAROMYCES-CEREVISIAE

Thirty-three neomycin- and temperature-sensitive mutants of Saccharomyces cerevisiae were isolated and characterized. The mutation fell into 29 complementation groups of neomycin sensitive mutations (nes). At the restrictive temperature (37°C), ten mutants arrested at specific stages in the cell division cycle: four at early G1 stage, two at late G1 stage, one at S phase, and three at G2 stage. None of the G1-arresting mutants isolated in this experiment appeared to be allelic with cdc mutants examined, suggesting that these are new cdc mutants. The nes mutants were further characterized by determining their cross-sensitivity to G418, cycloheximide, LiCl and CaCl2.