Molecular Links Between the Body’s Internal Clock and the Immune System

The immune system is influenced by the circadian clock through multiple molecular interactions.

• Circadian rhythms in the immune system are linked to direct interactions between circadian clock components and immune system components.
• Circadian clock proteins function as transcription factors, regulating the expression or repression of immune genes.
• Histone modifications, such as acetylation and methylation, are involved in circadian control of gene transcription and inflammatory proteins.
• Circadian clock proteins can physically interact with key inflammatory pathways, including members of the NFκB protein family.
• The immune system may also influence circadian clock function, indicating a reciprocal relationship between the two systems.

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