The internal, biological clock helps people, animals and plants to anticipate and adapt to the regular rhythm of the day.
"This years Nobel laureates have... solved the mystery of how an inner clock, in most of our cells in our inner bodies, can anticipate daily fluctuations between night and day, to optimise our behaviour and physiology," said Thomas Perlmann, the chairman of the Nobel Committee at the Karolinska Instiute, as he announced the winners.
The laureates studied fruit flies, and managed to isolate a gene that controls the daily biological rhythm. According to a statement from the Nobel Assembly at the Karolinska Institute, the laureates have "showed that this gene encodes a protein that accumulates in the cell during the night, and is then degraded during the day. Subsequently, they identified additional protein components of this machinery, exposing the mechanism governing the self-sustaining clockwork inside the cell."
This biological clock regulates for example behaviour, hormone levels, sleep, body temperature and metabolism. For us humans, the well-being is affected when our own internal clock does not match with the external environment, like when we travelling across time zones and experience jet lag.
"There are also indications that chronic misalignment between our lifestyle and the rhythm dictated by our inner timekeeper is associated with increased risk for various diseases," the Nobel Assembly wrote in its statement.
All three of the laureates of this year's Medicine Prize are Americans. Jeffrey C. Hall works at the University of Maine, Michael Rosbash at Brandeis University in Massachusetts and Michael W. Young at Rockefeller University in New York.