Circadian Clock’s Inner Gears
It was largely known that circadian clocks or the biochemical oscillators control many bodily processes such as physiology, metabolism, and behavior on a 24-hr cycle, but the molecular mechanisms which run these clock systems were not known. A Research team from Harvard Medical School led by Dr. Charles Weitz found that a set of important clock proteins shape up themselves into molecular machines to control the exact working structure of circadian rhythms. The results were published in the journal Molecular Cell.
The key proteins (molecular machines) involved in the clock system include 3 different period proteins (PER); 2 different cryptochrome proteins (CRY) and casein kinase-1 (CK1) and these proteins bind to other protein called CLOCK-BMAL1. There is a feedback loop formed that is the production of PER and CRY and these get attached to CLOCK-BMAL1 and the shut down of PER and CRY production in order that the whole process can start again, where this whole process takes about 24hrs. Along with these 6 clock proteins, there were 30 other adjunct proteins. The 6 proteins-complex is also called the upper complex also had a 7th protein GAPVD1, whose role was unknown earlier but it also plays an important role in the clock.
Dr. Weitz said, “The circadian clock is a very deep timing system that controls a large part of the physiology and behavior of all cells in the body to shape multiple processes. The more we learn about it, the more links we’ll get to certain kinds of disease states that aren’t easily amenable to treatment today. Now that we understand how these molecular machines are built, we can start asking questions about how they work”.