Brain control of the liver’s daily biological clock

Microarray analysis has shown that many genes, including clock genes, exhibit a circadian rhythm in the liver.

• Clock genes are expressed not only in the suprachiasmatic nucleus (SCN) but also in various brain regions and peripheral tissues.
• The liver shows a clear circadian rhythm in the expression of clock genes.
• Clock genes may play a critical role in the molecular mechanisms of both the SCN and the liver.
• The SCN controls the oscillation of clock genes in the liver through circadian clock mechanisms.
• Communication between the SCN and peripheral tissues involves the autonomic nervous system.
• Further studies are necessary to clarify the resetting signals affecting liver clock function.

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