Horacio de la Iglesia first got hooked on biology as an undergraduate in Argentina when he happened to notice a natural phenomenon: at certain times of the day crabs hid into their sand-plugged burrows, and at other times of the day they were all out on the beach.  His interest was piqued.  What drove their behavior?  Was there a method to their madness?  A mentor's interest in scientific research inspired Horacio to "value experimental evidence as a way of gathering information."  Equipped with this new philosophy, Horacio began to bring crabs into the lab and study their behavior.  The rest, as they say, is history…

Horacio joined the UW Department of Biology in 2003 after receiving a Ph.D. from the University of Massachusetts at Amherst and completing a post-doc at the University of Massachusetts Medical School. He continues to research how intertidal organisms synchronize their biology to the tides, but now spends most of his time researching circadian rhythms in mammals.

Research on mammalian circadian rhythms finds practical application in the biomedical sciences.  For example, Horacio's lab investigates the physiological effects of jet lag using the rat as a model organism.  In short, when normal circadian rhythms are challenged, say by jet lag, the body becomes "internally desynchronized" meaning normally tightly correlated cycles become decoupled.  For instance, your body's temperature fluctuates and it is normally at its minimum while you sleep.  Likewise, different hormones are secreted at certain times and in different quantities during the sleep-wake cycle.  However, when a body is internally desynchronized, these changes in temperature or hormone secretion may actually occur out of synch from your sleep-wake cycle.  Such an outcome wrecks havoc on the body leaving people tired, moody, and suffering from insomnia.

Though the short-term effects of being internally desynchronized are debilitating in their own right, the long-term effects can be quite serious: increased likelihood of reproductive anomalies such as shortened pregnancies and an increased risk of depression, cardiovascular disease, and cancer.  Why being internally desynchronized for long periods of time raises the risk of such maladies is still largely a mystery.  Most of us are internally desynchronized rarely, say from the occasional flight across time zones, but it is a chronic condition for people in more extreme situations: trans-meridian flight pilots are perpetually jet-lagged; night-shift workers are often internally desynchronized for the length of their employment; submariners live in artificial light/dark environments for months at a time, typically working 18-hour days.

Interestingly, circadian rhythms change naturally throughout an organism's life cycle.  For example, teenagers are actually programmed to stay up later and wake up later.  However, in order to attend morning classes, teenagers have to wake up earlier than their circadian clock dictates, causing them to become internally desynchronized.  Fortunately, within the last several years many school districts have started delaying high school start times in response to this discovery.  The results appear promising: participating schools have reported a significant decrease in drop out rates and an increase in average grades (particularly in early morning classes), and students have reported feeling less depressed.

Presently Horacio's lab is investigating the neural basis of circadian rhythms. The identification, by other labs, of the genes that constitute the gears of circadian clocks was the first step towards finding a remedy for people who are regularly internally desynchronized.  Several genes controlling circadian rhythm have been identified in mammals.  Mutations of these genes are known to cause alterations in circadian rhythms, or, more seriously, complete loss of circadian rhythmicity.  Horacio knows where and when in the brain these genes are expressed; the next step is to determine how these patterns of expression are affected by challenges that induce internal desynchronization.

For more information on Horacio's research visit his lab website, which can be found through the Department of Biology's website: http://www.biology.washington.edu.  In addition, Horacio will be attending the Biology Alumni Reunion Event on April 28th.  Please visit our website for more information on registering for that event.