The circadian clock has the extraordinary ability to run according to a periodicity of approximately 24 hours in 1 day, related to the earth’s rotation. The body clock controls all bodily rhythms, including sleep, blood pressure, and body temperature. In one extremely limited region of the mammalian brain (the suprachiasmatic nucleus or SCN), there are groups of 16-thousand cells that act as master clocks, creating circadian rhythms. There are also secondary clocks throughout the mammalian body, which are controlled by the master clocks. These clocks produce a rhythm by working together like a conductor and the orchestral players. If the rhythm breaks down, the body experiences circadian rhythm abnormalities that produce both psychological and physical disorders. Such circadian rhythm abnormalities are a major problem for society.

The Institute Molecular and Cell Biology at the National Institute of Advanced Industrial Science and Technology (AIST) has established a method to manipulate the functional molecules of the biological clock. This research may provide clues to curing circadian rhythm abnormalities. Using restriction enzymes that cut genetic material, the researchers cut out a portion of the period gene to create the deleted gene, and transferred the artificial gene into a cell so that the cell was able to produce that mutant molecule. Through this simple procedure, the researchers were able to destroy the clock function.

As well as contributing to future research to solve circadian rhythm abnormalities, these results should enable the development of useful animal models whose biological rhythms can be manipulated.

The results of this research were published in the journal Molecular and Cell Biology (October 21, volume 21, issue 19).