Fig. 5.

Calorie restriction reduces rDNA recombination. The rDNA silencing reporter parent strain, JS128, the control JS122 strain, and isogenic fob1Δ and sir2Δ strains were serially cultured in YP media containing the indicated glucose concentrations for approximately 120 generations. These were then spread onto YPD plates and then replica plated onto both SC and −ura plates. Marker loss per generation was calculated by dividing the number of colonies that did not grow on −ura plates by the total number of colonies on replica SC plates and dividing this value by the total number of generations. In total, 73 000 colonies were counted for (A) and 69 000 colonies for (B). Each graph represents pooled data normalized to the appropriate JS128 parent 2% glucose control value, expressed as mean + standard error of the mean. Statistical analysis was performed using Student’s t-tests (*P<0.05).