Jet lag: almost everyone has suffered from it at one time or another. It happens when a person's interior, biological clocks become out-of-sync with the environment. Biological clocks control a number of different important processes, such as the wake-sleep cycle and when our stomach begins growling. Despite its importance, these clocks remain a major mystery. Scientists are just beginning to figure out how they work and why they are so important. Now, a research team headed by Carl Johnson from Vanderbilt has taken a major step forward in understanding what makes biological clocks tick. They have determined the basic structure of a biological clock protein for the first time. This protein comes from a species of blue-green algae - better known as green pond scum - which is the simplest organism known that has an internal clock.

By David F. Salisbury
December 13, 2002