Light-sensitive Neuropsin controls daily clock genes and light-based timing in mouse skin

Light exposure can phase shift skin circadian rhythms, which requires Opn5 gene function.

• Nearly all mammalian tissues possess autonomous circadian clocks that need synchronization to a 24-hour day.
• Melanocyte precursor cells in hair and vibrissal follicles express a photopigment called neuropsin (OPN5).
• Organotypic cultures of murine skin can entrain to light-dark cycles, relying on a specific chromophore and the Opn5 gene.
• Short-wavelength light can significantly alter skin clock rhythms in a manner dependent on Opn5.
• In specific mice unable to behaviorally synchronize to light-dark cycles, skin clock gene expression remains aligned with the light-dark cycle, while other clocks do not.

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