Glial cells of the nervous system, once thought to function strictly as support cells for neurons, are now thought to actively modulate them.
Providing further evidence in support of this theory, researchers at the Department of Neuroscience and the Center for Neuroscience Research (CNR) at Tufts University School of Medicine (TUSM) recently identified a specific population of glial cells that is required for the control of circadian behavior in Drosophila (the fruit fly). Their findings, which confirm and extend their earlier work, are published in the August 2, 2007, issue of Neuron.
"Our results suggest that an autonomous glial mechanism may drive circadian rhythms in the activity of a Drosophila protein known as Ebony," says F. Rob Jackson, PhD, director of the CNR and professor of neuroscience at TUSM. "Ebony activity and the glia containing that activity, explains Jackson, "function independently of, or in concert with, other brain cells (neurons) to control circadian behavior."
"Most organisms," says Jackson, "from Drosophila to humans, have the ability to adapt the timing of behavior or other processes to environmental cycles using an intrinsic time-keeping device called a circadian clock." While previous studies have suggested that glia may be required for normal circadian behavior, specific glial factors that are needed for this process had not been identified.