Star-shaped cells called astrocytes, long considered boring, “support cells,” are finally coming into their own. To everyone’s surprise they even play an important role in the body’s master clock, which schedules everything from the release of hormones to the onset of sleepiness.
A small molecule called VIP, known to synchronize time-keeping neurons in the brain’s biological clock, has the startling effect of desynchronizing them at higher dosages, says a research team at Washington University in St. Louis. Neurons knocked for a loop by a burst of VIP are better able to re-synchronize to abrupt shifts in the light-dark cycle like those that make jet lag or shift work so miserable.
In the June 5 issue of Neuron, WUSTL biologist Erik Herzog and his colleagues report the discovery of a crucial part of the biological clock: the wiring that sets its accuracy to within a few minutes out of the 1440 minutes per day. This wiring uses the neurotransmitter, GABA, to connect the individual cells of the biological clock in a fast network that changes strength with time of day.
Eric ChouTesting the wake-sleep cycleA biologist at Washington University in St. Louis and his collaborators have identified the factor in mammalian brain cells that keeps cells in synchrony so that functions like the wake-sleep cycle, hormone secretion and loco motor behaviors are coordinated daily.
“I smell a rat!” Researchers have found that the sense of smelling in mice is affected by a biological clock devoted entirely to olfaction — smelling stuff, like sleeping and waking, is on a daily cycle.Biologists at Washington University in St. Louis have discovered a large biological clock in the smelling center of mice brains and have revealed that the sense of smell for mice is stronger at night, peaking in evening hours and waning during day light hours. A team led by Erik Herzog, Ph.D., Washington University associate professor of Biology in Arts & Sciences, discovered the clock in the olfactory bulb, the brain center that aids the mouse in detecting odors. More…
Photo by David Kilper / WUSTL PhotoHimadri Pakrasi explains the photobioreactor in his Rebstock Hall laboratory.The United States Department of Energy (DOE) has devoted $1.6 million to sequencing the DNA of six photosynthetic bacteria that Washington University in St. Louis biologists will examine for their potential as one of the nextgreat sources of biofuel that can run our cars and warm our houses. That’s a lot of power potential from microscopic cyanobacteria (blue-green algae) that capture sunlight and then do a variety of biochemical processes. One potential process, the clean production of ethanol, is a high priority for DOE. Himadri Pakrasi, Ph.D., Washington University Professor of Biology in Arts & Sciences, and Professor of Energy in the School of Engineering and Applied Science, will head a team of biologists at Washington University and elsewhere in the analysis of the genomes of six related strains of Cyanothece bacteria. More…
Photo by David Kilper/WUSTL PhotoErik Herzog, Ph.D., and graduate student Rachel Huckfeldt attach electrodes to a multielectrode array.Getting over jet lag may be as simple as changing the temperature —your brain temperature, that is. That’s a theory proposed by Erik Herzog, Ph.D. assistant professor of biology in Arts & Sciences at Washington University in St. Louis. Herzog has found that the biological clocks of rats and mice respond directly to temperature changes.