Figure 4. DMH-specific Prdm13-knockout mice display sleep alterations observed in aged C57BL/6J mice.

(A) Breeding strategy to generate DMH-specific Prdm13-knockout (Prdm13-KO) mice. After crossing Prdm13 ^fl/f; Rosa26R^{ZsGreen/ZsGreen} mice and Nkx2-1^CreERT2/+; Prdm13 ^fl/fl mice, Prdm13 ^fl/fl; Nkx2-1^CreERT2/+; Rosa26R^ZsGreen/+ mice were used as Prdm13-KO mice and Prdm13 ^fl/fl; Nkx2-1^+/+; Rosa26R^ZsGreen/+ mice were used as control (Cont) mice. (B) Expression of Prdm13 in the DMH, tuberal nucleus (TN), and amygdala (Amg) of Prdm13-KO and Cont mice (n = 5). Values are shown as means ± S.E., **P < 0.01, ***P < 0.001, and non-significant (ns) by two-way ANOVA with Bonferroni’s post hoc test. (C, D) Number of episodes (C) or duration (D) of wakefulness (top), NREM sleep (middle), and REM sleep (bottom) every 3 h through a day (left) and during the light (L) and dark (D) periods (right) in Prdm13-KO and Cont mice. Shading indicates dark period (n = 6). Values are shown as means ± S.E., #P < 0.05 by repeated measures ANOVA, listed P-values and *P < 0.05 by repeated measures ANOVA with Bonferroni’s post hoc test (left) or unpaired t test (right). (E) Number of sleep attempts during SD from 6 am to 8 am (6–8), 8 am to 9 am (8–9), 9 am to 10 am (9–10), 10 am to 11 am (10–11), and 11 am to 12 pm (11–12) in Prdm13-KO and Cont mice (n = 13–14). Values are shown as means ± S.E., *P < 0.05, ***P < 0.001 by repeated measures ANOVA with Bonferroni’s post hoc test. (F) SWA during NREM sleep after SD. Normalized power is relative to the average of the 24-h baseline day each group (n = 6). Values are shown as means ± S.E. (G) EEG spectra of wakefulness (left), NREM sleep (middle), and REM sleep (right) during the light period (n = 5–6). Values are shown as means ± S.E. (H) Total amount of wakefulness, NREM sleep, and REM sleep during a 24-h period (24 h total), 12-h light period (12 h light) or 12-h dark period (12 h dark) (n = 6). Values are shown as means ± S.E.