Isolation of temperature-sensitive (ts-) mutants defective in the progression of the cell division cycle in Schizosaccharomyces pombe

Abstract

he temperature sensitive (ts~) mutants of Schizosaccharomyces pombe defective in cell cycle progression were isolated by EMS mutagenesis, and characteristics of these mutants were examined by their morphological changes, histochemical examination of cytoskeletal structure, and DNA content analysis by flow cytometry at a restrictive temperature of 37 °C. Out of 181 ts~ mutants obtained from the 2.5 父 10s mutagenized S. pombe cells, 51 mutant cells were shown to have defects in cell cycle progression. The DNA content analysis of the mutants enabled us to classify 20 mutants to be Gi or Gi/S phase defective mutants, 6 mutants to be S phase defective mutants, and 25 mutants to be Gj/M phase defective mutants. Thus, these new cell cycle stage specific mutants will in S. pombe.