The protein TIEG1 controls the Bmal1 gene to regulate the body’s internal clock

Diurnal variation of Tieg1 mRNA and nuclear TIEG1 protein levels was observed in the mouse liver, with peaks at day/night transition and midnight.

• The circadian clock regulates daily rhythms in various physiological processes and is influenced by external cues such as light and feeding.
• TIEG1, a transcriptional repressor, was found to bind to the Bmal1 gene promoter, inhibiting its transcriptional activity.
• The repression of Bmal1 by TIEG1 is additive to the repression exerted by REV-ERBalpha, another known repressor.
• Knock-down of TIEG1 using siRNA resulted in a shortening of cellular bioluminescence rhythms associated with Bmal1 and Per2.
• These observations suggest TIEG1 plays a significant role in regulating the normal oscillation of the circadian clock.

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