Jeffrey Hall, Michael Rosbash, and Michael Young have won the Nobel Prize for Physiology or Medicine for their research on the circadian rhythm. This is what makes you get tired at night and wake up in the morning. It’s your biological clock. It not only affects your own sleep patterns, but large parts of our society: work schedules, school performance, peak traffic times – they are all based on the fact that our circadian rhythms are all pretty much the same.
Several genes determine our internal biological clock. The circadian rhythm researchers were awarded the Nobel Prize for the discovery of the period gene. This gene produces the protein PER which inhibits its own production. This causes the level of PER protein to cycle continuously: When levels are high, it stops more PER being formed, until levels are low, and it starts producing more again. This all happens over a period (hence the name!) of about 24 hours. Although it was discovered in fruit flies, we all have a similar biological mechanism that runs our biological clock.
There are other genes involved as well, all collaborating to make sure that we wake up when the day starts, and go to bed at night. It doesn’t always work perfectly. Some people have a shorter circadian rhythm, others a longer one. Teenagers tend to wake up much later than either children or adults, just at the time in their life when teachers expect them to be wide awake for a 9AM science class. Some people are natural morning people, other’s night owls.
I just messed with my own biological clock this weekend by returning from a transatlantic trip. Jet lag is caused by the body’s circadian rhythm not catching up fast enough with the change in daylight. It takes a while to adjust. So on Monday morning, when I was still jetlagged while watching the Nobel Prize announcement, I was already very aware of circadian rhythms even before I even heard who won!
Hall, Rosbash and Young were the first Nobel Laureates to be announced this year. They will receive their prize in Stockholm in December, together with the winners of the other prizes announced over the course of this week.