Circadian gene expression in the SCN of <i>Cry1^-/-</i> and <i>Cry2^-/-</i> mice.

<p>Relative mRNA expression profiles of core clock genes <i>Bmal1</i> (A) and <i>Per2</i> (B) and the clock-controlled genes <i>Dbp</i> (C) and <i>Pk2</i> (D) in the SCN of light entrained (LD) wild type (black), <i>Cry1^-/-</i> (green) and <i>Cry2^-/-</i> (red) mice, as measured by RT-qPCR. For each genotype, mRNA levels (mean ± s.e.m) are expressed relative to the peak of expression (set at 100%) and fitted with a wave curve. The two-way ANOVA test revealed a significant effect of genotype and time interaction (*p<0.05). Data at ZT0 and ZT24 are double-plotted for easier visualization of daily expression. The bar above panels indicates time of light on and off.