Our circadian clock is the part of our brain the regulates our body's cycle, making sure that we sleep, eat and act in concordance with the twenty-four-hour day.
Even though we know it's there and what it does, picking apart the mechanisms of its action has been a long and laborious process for scientists. New research has unlocked one more part of this biohorological puzzle.
There's an ongoing negative feedback loop occurring in our body which the circadian rhythm relies on. The group of proteins known as PER complex inhibit the activity of a transcription factor, called CLOCK-BMAL1. Once inhibited, this represses the expression of the PER proteins, and the cycle sways again.
http://io9.com/5812724/sleep-scientists-are-tinkering-with-our-circadian-clocks