Researchers have created the first Per2LUC transgenic Syrian hamster, enabling real-time bioluminescence imaging of circadian clock function across multiple tissues, according to a study published in the Journal of Biological Rhythms.
The Per2LUC model expresses a PER2::luciferase fusion protein, producing measurable bioluminescence rhythms that reflect the molecular state of the circadian clock in living tissue. While Per2LUC mice have been a cornerstone of circadian research for nearly two decades, the Syrian hamster (Mesocricetus auratus) offers distinct advantages for studying circadian physiology, including a well-characterized circadian phenotype and the historically important tau mutation that shortens the endogenous period.
What they found. The team, led by Yanan Liu, Jennifer A. Evans and Eric L. Bittman, characterized behavioral rhythms and ex vivo bioluminescence rhythms from multiple tissues in the new model. Properties of bioluminescence rhythms varied by tissue type in the Per2LUC hamster, but the overall pattern was similar to that displayed by tissues from the Per2LUC mouse. This cross-species consistency validates the model while offering a new platform for circadian research in a species with unique genetic and physiological tools.
Why it matters. The Syrian hamster has been central to circadian biology since the discovery of the tau mutant in 1985, the first mammalian circadian mutant identified. However, the lack of genetic reporters for real-time clock monitoring in hamsters has limited mechanistic studies. The Per2LUC hamster fills this gap, enabling investigators to track circadian dynamics at the molecular level across tissues (SCN, liver, lung, etc.) in a species that naturally displays robust behavioral rhythms and is amenable to surgical and pharmacological manipulations that are difficult in mice.
Bottom line. The Per2LUC Syrian hamster extends the bioluminescent reporter toolkit to a second rodent species, providing a platform for studying circadian clock dynamics in a model with unique advantages for reproductive, photoperiodic, and seasonal rhythm research.
Source. Liu Y, Roszkowski E, Li R, Sisson C, Landman E, Weaver DR, Wang Z, Evans JA, Bittman EL. “Circadian Behavioral and Bioluminescence Rhythms in the Per2LUC Syrian Hamster.” Journal of Biological Rhythms. 2026. doi:10.1177/07487304261459487.