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bioRxiv · 10.1101/2020.07.25.221101

The sleep-wake distribution contributes to the peripheral rhythms in PERIOD-2

Hoekstra, M. M. B.·Jan, M.·Emmenegger, Y.·Franken, P.
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Abstract

In the mouse, Period-2 (Per2) expression in tissues peripheral to the suprachiasmatic nuclei (SCN) increases during sleep deprivation and at times of the day when animals are predominantly awake spontaneously, suggesting that the circadian sleep-wake distribution directly contributes to the daily rhythms in Per2. We found support for this hypothesis by recording sleep-wake state alongside PER2 bioluminescence in freely behaving mice, demonstrating that PER2 increases during spontaneous waking and decreases during sleep. The temporary reinstatement of PER2 rhythmicity in behaviorally arrhythmic SCN-lesioned mice submitted to daily recurring sleep deprivations substantiates our hypothesis. Mathematical modelling revealed that PER2 dynamics can be described by a damped harmonic oscillator driven by two forces: a sleep-wake-dependent force and a SCN-independent circadian force. Our work underscores the notion that in peripheral tissues the clock gene circuitry integrates sleep-wake information and could thereby contribute to behavioral adaptability to respond to homeostatic requirements.

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Hoekstra, M. M. B., Jan, M., Emmenegger, Y., Franken, P.. 2020-07-26. The sleep-wake distribution contributes to the peripheral rhythms in PERIOD-2. https://doi.org/10.1101/2020.07.25.221101

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