Journal of Molecular Imaging & Dynamics
Acesso livre

Abstrato

Gene expression of the clock gene in moving mice in multiple tissues

Francesco Clerici

In animals, a master clock in the Supra Chiasmatic Nucleus (SCN) regulates circadian rhythms in physiology and behaviour (SCN). Clock genes play an important role in the expression of cellular circadian rhythms, which are principally controlled by a cell-autonomous molecular feedback loop1. Clock gene expression is not restricted to the SCN, as it can be seen in a wide range of organs. However, outside of the SCN, the expression pattern of clock genes is poorly understood, partly due to a lack of tools for simultaneously monitoring circadian clock gene rhythms in specific tissues and detecting output functions in the absence of physical limitations. The bioluminescent reporter enzyme firefly luciferase (luc) and its substrate D-luciferin (luciferin) have been successfully adapted to whole-body imaging of clock genes in anaesthetized mice using a charge-coupled device (CCD) camera, and have been used to generate optical imaging signals with high sensitivity in living animals. Anaesthesia, on the other hand, has been shown to change the expression of the clock gene. Saini used a CCD camera outside the body to assess rhythmic bmal1 expression solely in the liver of a freely moving mouse.