The EFF the effect of dietary restriction of MYC protooncogene expression in mice: A preliminary study

Abstract The effect of chronic dietary restriction on the expression of the c -myc protooncogene was determined in the livers of a hybrid mouse strain (C57B16 × C3H F1 hybrid) at three time points during a 24-h period: 1 h after lights on (1 HALO), 5 h prior to feeding (12 HALO), and 2 h after feeding (19 HALO). In addition, in whole animals studies, changes in core body temperature were monitored. In mice which had been subjected to a chronic diet restriction (60% of the intake of ad libitum controls), c -myc expression was significantly reduced at 1 HALO and 19 HALO compared to corresponding ad libitum animals. In addition, significant differences in c -myc expression were found between time points, in both the ad libitum and restricted groups, suggesting that myc protooncogene expression in the liver may be regulated in a circadian fashion. C -myc expression may correlate with body temperature, suggestng a possible association with metabolic output.