Peroxiredoxin protein chemical cycles and their role in keeping time without gene activity

Circadian oscillations in the redox status of peroxiredoxins are conserved across organisms from archaea to animals.

• Genetic analyses have identified gene expression feedback loops as critical for circadian clock mechanisms.
• Post-translational modifications are increasingly recognized as important in regulating circadian timekeeping.
• Cellular metabolism, particularly redox homeostasis, is linked to the functioning of the circadian clock.
• Redox rhythms in peroxiredoxins occur independently of traditional circadian gene expression pathways.
• The findings suggest a potential noncanonical aspect of circadian timekeeping related to cellular redox status.

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