To verify that neural signals from the retina to SVS neurons and

To verify that neural signals from the retina to SVS neurons and the SCN core are functional, we measured induction of the immediate early gene c-fos in Sox14gfp/gfp and control mice before and after acute light exposure (aL) ( Figures S3A and S3B). During the dark period,

the SCN and the SVS do not express c-Fos, but the gene is strongly upregulated 1 hr after light exposure during the subjective dark phase ( Figure S3B). We could detect no major differences in c-Fos levels between Sox14gfp/gfp and control mice upon acute light exposure ( Figure S3B). We conclude that Sox14gfp/gfp mice have not lost the ability to transduce signals from the retina to their diencephalic targets. To assess whether Sox14gfp/gfp mice have a functional SCN capable of generating an endogenous circadian rhythm, we measured the period of three well-known Panobinostat circadian behaviors and physiological responses that are controlled by the SCN: motor activity, feeding episodes, and core body temperature. The intrinsic period of

the clock becomes apparent under constant dark (DD) conditions. As expected, wild-type mice show a free-running circadian period shorter than 24 hr for all three parameters recorded. Sox14gfp/gfp mice displayed circadian behaviors with a free-running period similar to control mice ( Figures selleck chemical 7A–7C) (ambulations: wild-type 23.8, Sox14gfp/gfp 23.6; feeding episodes: wild-type 23.7, Sox14gfp/gfp 23.4; core body temperature: wild-type 23.7, Sox14gfp/gfp 23.5; median). We then reintroduced the light variable with the normal 12 hr light and 12 hr dark (LD) cycle. Under these conditions, both control mice and Sox14gfp/gfp mice adjusted their circadian rhythms in motor activity, feeding, and core body temperature,

giving periods very close to 24 hr ( Figures 7A–7C) (ambulations: wild-type Mephenoxalone 24.0, Sox14gfp/gfp 24.0; feeding episodes: wild-type 24.0, Sox14gfp/gfp 24.0; core body temperature: wild-type 23.8, Sox14gfp/gfp 24.0; median). The retained ability of Sox14gfp/gfp mice to respond to environmental light changes was also shown under a 6 hr LD phase advance experiment ( Figure S5B). Strikingly though, in Sox14gfp/gfp mice, the phase of all three circadian outputs did not align to the phase of the light cycle ( Figures 7E, 7G, 7I, and S5A–S5C). As a consequence of their advanced phase onset, mutant mice displayed increased ambulations during the L phase and decreased ambulations in the D phase compared to controls ( Figure 7D) (percentage, daily average ambulations in L phase: wild-type 14.9% ± 0.6%; Sox14gfp/gfp 47.1% ± 1.8%; average ± SEM). Similarly, both the onset of feeding and elevation of body temperature were phase advanced. This is shown in Figure 7, which compares feeding ( Figure 7F) and body temperature ( Figure 7H) in the 2 hr before D onset and the 2 hr before L onset for each genotype (percentage of daily average feeding: wild-type L 4.6% ± 0.6%, D 10.0% ± 1.

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