Circadian clock like an orchestra with many conductors

March 27, 2014

Science Daily/University of Michigan

You've switched to the night shift and your weight skyrockets, or you wake at 7 a.m. on weekdays but sleep until noon on weekends -- a social jet lag can fog your Saturday and Sunday. Life runs on rhythms driven by circadian clocks, and disruption of these cycles is associated with serious physical and emotional problems.

"The finding shows that instead of the entire orchestra following a single conductor, part of the orchestra is following a different conductor or not listening at all," Shafer said. The findings suggest that instead of a group of master pacemaker neurons, the clock network consists of many independent clocks, each of which drives rhythms in activity. Shafer and Yao suspect that a similar organization will be found in mammals, as well.

"A better understanding of the circadian clock mechanisms will be critical for attempts to alleviate the adverse effects associated with circadian disorders," Yao said.

Disrupting the circadian clock through shift work is associated with diabetes, obesity, stress, heart disease, mood disorders and cancer, among other disorders, Yao says. The International Agency for Research on Cancer classified shift work that disrupts circadian rhythms as a human carcinogen equal to cancer-causing ultraviolet radiation.

http://www.sciencedaily.com/releases/2014/03/140327142443.htm