Circadian rhythm clocks in different animals

We have circadian rhythms for all kinds of body functions and behaviors. Not only us, but animals and insects do too. It’s on a bigger scale than just environmental, although that definitely plays a role. Many scientists have studied this on a molecular level and have discovered many interesting things that seem to be common findings across several experiments. 

In the research article “Central and Peripheral Clock Control of Circadian Feeding Rhythms”, Dr. Cavanaugh and his colleagues researched the different types of circadian rhythms in Drosophila fruit flies. They realized that there were different circadian clocks for different functions that were located in various parts of the body. Some of these clocks depend on various environmental factors; for example when it’s constantly dark out, the fat body gene in the Drosophila becomes under the control of the central clock. They concluded that there are central brain clocks that control feeding, courtship/mating, learning/memory, etc, that are supported by peripheral clocks that can regulate feeding behavior. 

In the article “Integration of feeding behavior by the liver circadian clock reveals network dependency of metabolic rhythms”, Greco et al. researched the effects of BMAL 1 and its transcription factor CEBPB, and found that when the two work together they regulate the functions of daily liver metabolic transcription programs. They discovered this by separating the interaction between the feeding and liver clock. 

These discoveries are interesting because Greco proved Cavanaugh’s idea that there are different circadian clocks in different parts of the body. By spending more time researching the way similar clocks work in different specimens, we might be able to use the data from one study as the baseline information for another experiment or be able to fix an issue in one of those clocks in another animal.