June 6, 2007 -- Herman Wijnen, assistant professor of biology, recently won a $50,000 Fund for Excellence in Science and Technology (FEST) Distinguished Young Investigator grant for his research into the effects of environmental temperature on circadian rhythms.

 This FEST grant program is administered through the Office of the Vice President for Research and Graduate Studies and aims to reward faculty in their first three years at U.Va. with funding for their pioneering research proposals.
 
“Herman is one of our most promising young scientists,” notes Douglas Taylor, chair of the Department of Biology, in a letter of support for Wijnen’s FEST proposal.  “He is doing cutting edge research, applying the most modern genomic methods to the study of biological rhythms, a field of timely importance to the betterment of the human condition.”

Most living beings contain internal timekeeping mechanisms or biological clocks that regulate behaviors on about a 24-hour—or circadian—time cycle.  Circadian rhythms are commonly referenced in conjunction with human sleep patterns, but they affect many more physiological parameters, including blood pressure and body temperature.  “A fundamental property of circadian rhythms is that they persist if you take away external cues [such as light and darkness],” Wijnen explains.

Wijnen studies the molecular basis for circadian rhythms in the Drosophila, or fruit fly.  The fruit fly is a valuable model organism for such research not only because of the ease and convenience with which it is studied, but also because its genome is well understood and highly applicable to the human genome.  “If we look at the genes that govern the biological clock in fruit flies, they are very similar to the genes that govern the clock in humans,” notes Wijnen.  The clock genes of both humans and flies function in brain cells to govern sleep/wake rhythms, but they are also found in many other parts of the body, where they may control other overt rhythms. “One of the key problems that we are trying to solve is how clock gene activity in the brain connects to the sleep/wake cycle," says Wijnen.

Wijnen’s FEST project will investigate the complex relationship between clocks and environmental temperatures.  “Clocks are one of the few biological systems that run at the same speed over a wide range of temperatures,” notes Wijnen “yet they retain the ability to synchronize with daily cycles in environmental temperature.” 

A system of state-of-the-art monitors that is highly reliable, yet simple allows Wijnen to track fruit fly activity.  The system includes glass vials that each house individual flies and fit into a tray equipped with infrared beams and photosensors.  The tray is hooked up to a computer so that each time a fly crosses the beam, its movement is catalogued.   With this equipment, Wijnen can track the activity patterns of many as 1000 flies at a given time, and he can easily manipulate parameters such as temperature, light, and humidity for a variety of experimental conditions.   The FEST funding will be used towards related lab equipment and part of a lab technician’s salary.

“This behavioral assay has added a lot of power to our research,” says Wijnen.  “Using this assay we can randomly introduce mutations in fly DNA and screen for those genes that affect clock function.” 

Wijnen’s group has already identified fly strains that differ in their behavioral response to daily variations in temperature.  Now he plans to develop and use these reagents to isolate genes responsible for the entrainment of the flies’ clock to temperature, which will spawn a whole host of other research possibilities and potentially attract National Institutes of Health or National Science Foundation funding.  Such basic research is significant because it will not only advance our understanding of how biological clocks work, but will shed light on how they respond to seasonal changes in temperature—which may become especially pertinent in the wake of global warming.

Wijnen joined the strong set of research groups dedicated to the study of biological timing at U.Va. in December of 2004.  The recent hire of Joseph Takahashi, one of the world’s leading investigators in circadian biology, will further reinforce this area.  Takahashi will head a new Center for Circadian and Systems Biology at U.Va. beginning in September of 2008.

Written by Melissa Maki, research communications coordinator for the Office of the Vice President for Research and Graduate Studies.