A Nobel prize for medicine for the understanding of body clocks
This year, three of the prize-winners may be particularly appreciative of that, for they are some of the scientists who have helped to explain why jet lag exists in the first place.
.. Jeffrey Hall, Michael Rosbash and Michael Young are, between them, responsible for working out how the endogenous clocks of fruit flies—and, by extension, of other organisms—run what is known as the circadian rhythm. This is the internal cycle (circa is the Latin for “about” and dies the Latin for “day”) that matches the body’s physiology to the alternation of light and darkness caused by Earth’s rotation. In human beings it controls, among many other things, sleep patterns.
.. Between them, studying mutated fruit flies, they put together an explanation of what is going on at a molecular level.
..Their first step, in 1984, was the isolation within the fruit-fly genome of a gene called period, which had previously been found to be important in controlling circadian rhythms
.. Dr Hall and Dr Rosbach then went on to measure the concentration in fly brains of the protein this gene encodes. They discovered that the protein’s concentration cycles predictably over the course of 24 hours, peaking at night. They also measured levels of the messenger molecule, produced by period genes, which carries the recipe for the protein to a cell’s protein-making machinery. That, too, cycles daily—peaking a few hours before concentration of the protein itself is at its highest.
.. The crucial part of the story is that the protein inhibits the action of periodgenes. The more of the protein there is, the less active the genes are. That reduces production of the messenger molecule, which reduces production of the protein, which permits the gene to reactivate. And so on.