Brain And Muscle Arnt-Like Protein-1 (BMAL1) Controls Circadian Cell Proliferation And Susceptibility To UVB-Induced DNA Damage In The Epidermis

July 2012 in “ Proceedings of the National Academy of Sciences of the United States of America ”

Mikhail Geyfman, Vivek Kumar, Qiang Liu, Rolando Ruiz, William Gordon, Francisco Espitia, Éric Le Cam, Sarah E. Millar, Padhraic Smyth, Alexander Ihler, Joseph S. Takahashi, Bogi Andersen

BMAL1 circadian clock cell proliferation UVB-induced DNA damage epidermis DNA repair UVB radiation circadian rhythms skin health environmental stressors UVB damage

TLDR BMAL1 controls skin cell growth and UV damage risk, peaking at night.

The study demonstrated that the circadian clock protein BMAL1 played a crucial role in regulating cell proliferation and the skin's susceptibility to UVB-induced DNA damage. Researchers found that BMAL1 controlled the timing of cell division in the epidermis, which affected the skin's vulnerability to UVB radiation. Mice lacking BMAL1 showed increased DNA damage and reduced repair capacity when exposed to UVB light, highlighting the importance of circadian rhythms in skin health and protection against environmental stressors.