The Nobel Prize in Physiology or Medicine was awarded this morning to Jeffrey C. Hall, Michael Rosbash, and Michael W. Young, all American scientist that have worked to unravel the biomolecular underpinnings of our circadian rhythms.
Circadian rhythms are biological patterns that tell your body when to sleep and when to eat, when to raise your blood pressure and when to lower your body temperature.
These are ancient mechanisms exhibited, in some way, by all life. Even single-celled organisms like bacteria set up these internal cycles to respond to their changing environments.
It has been known that there is some kind of internal clockwork in living things since 1729, when French astronomer Jean Jacques d’Ortous de Mairan noticed a mimosa plant opening and closing its leaves as if it were welcoming the sun even though he kept the plant in a dark room.
How these rhythms are maintained was a mystery until Hall, Rosbash, and Young emerged on the scene. Working in tandem across two labs, the trio identified genes in mutant flies that seemed to govern their sleep patterns.
After further research, they developed a theory called the Transcription-Translation Feedback Loop (TTFL), in which a cascade of genes with fun names like period, timeless, and clock pump out proteins that interact with each other and other molecules to keep track of time. There are also some proteins in the system that react to sunlight, which keeps the TTFL synced up to a day-night cycle.
All these interactions loop back around and affect the rate the genes create these proteins in the first place, which sets up an internal clock other mechanisms within the cell can use for reference.
Circadian rhythms are crucial to maintaining a healthy and happy life. Disrupting them can prove disastrous: circadian rhythm mix ups are likely carcinogenic and research subjects who lived in dark caves for months at a timespeak of emotional distress. Messing with circadian rhythms by keeping people awake for extended periods of time is considered torture, and is in fact illegal by UN proclamation.
This award, as many do, came as a surprise. Hall, Rosbash, and Young were not on our prediction list–we’ll see tomorrow if we get one right for the Physics Nobel announcement.