Correlation among turnover of nucleic acids, ribonuclease activity and sporulation ability of Saccharomyces cerevisiae.

The turnover of nucleic acids and changes in ribonuclease activity during sporulation of Saccharomyces cerevisiae were studied. In the sporulating strains, 37-58% of vegatatively synthesized RNA were degraded during the sporulation process. The degree of degradation of vegetative RNA was proportional to the sporulation ability. In the non-sporulating strains, the degradation of vegetative RNA was less than 28% in the sporulation medium. Accompanied by the degradation of vegetative RNA, a ribonuclease activity increased several times during sporulation. We have found a close relation among the sporulation rate, the degree of the degradation of vegetative RNA and the increase in ribonuclease activity in the sporulation medium, using cells of which sporulation ability was repressed by changing the age or carbon source in various degrees.