Figure 9. Ty1 reduces the reproductive potential of dividing cells. (A) Proportion of His+ cells in NQ or Q cell populations regrown in fresh medium at 30˚C overnight expressed as a percentage of the proportion of His+ cells in the populations prior to regrowth. (B) Relative decrease in the frequency of His+ cells per cell doubling in the populations regrown overnight for the data in panel A. (C) Plating efficiencies for mid-exponential (Exp, two days) and early stationary phase (Stat, four days) populations of S. paradoxus strains with zero, one to three (low), or about 20 (high) chromosomal copies of Ty1 grown at 20˚C and normalized to the values for the zero copy strain. Data are from five to nine trials. Three low copy and three high copy strains were used. (D) Percentages of cells with buds in strains with the indicated Ty1 copy number grown at 20˚C for seven days, determined by light microscopy. Buds less than or more than 50% the size of the mother cells were scored as small or large, respectively. Three low copy and three high copy strains were used and results are from five to six trials. All data are mean values with standard deviation. Single or triple asterisks indicate p<0.05 or 0.001, respectively.