Light-illumination effects on the cellular concentration of photolyase molecules in yeast

Abstract

The effects of light-illumination in the absence or presence of cycloheximide (CHX) on the number of photoreactivating enzyme molecules per haploid cell ofSaccharomyces cerevisiae (N _PRE) were investigated.N _PRE increased, when the cells were held in buffer in light in the absence of CHX for 24 or 48 h before UV-irradiation (buffer-holding). The increase ofN _PRE was clearly observed in cells, whoseN _PRE before bufferholding was small, that is, in stationary growth phase cells grown at 37° C and in logarithmic growing cells incubated at 30° C. In the case of buffer-holding in light in the presence of CHX or in the dark in the absence or presence of CHX, the increase ofN _PRE was small or not observed.