Engineers studying biological clock of fruit flies

8/31/04

The biological clocks that in humans are responsible for maintaining sleep cycles and other daily rhythms -- as well as the curse of jet lag -- are common to many creatures.

UCSB engineers and colleagues in Germany have been looking at how the clock is maintained in the fruit fly for lessons on how biological systems work at the cellular level.

The fly's biological clock is set by the sun. When it peeks over the horizon, the sun affects light-sensitive neurons in the fly's brain, setting off protein reactions. The rate of the reactions varies according to the brightness of the light.

It's these reactions that set the biological clock, and it's not easily disrupted.

Engineers at UCSB's Institute for Collaborative Biotechnologies and the Max Planck Institute for Dynamics of Complex Technical Systems in Germany are trying to figure out what makes this control system so robust -- "to unravel design principles in a complex biological system," said co-author Frank Doyle, a chemical engineer at UCSB.

In work described in this week's issue of the journal Proceedings of the National Academy of Sciences, the engineers took mathematical information from the copious literature on fruit flies -- one of the most commonly studied organisms in science -- to perform their computations and figure out how the clock system works.

They tweaked the model to find the weak links in the system -- an approach that might be a way to show that disease is a breakdown of a robust system, the authors said. It could also help in the design of treatments for such ailments -- and for jet-lagged travelers.

-- Anna Davison