Drosophila

IMAGE OF AN ADULT FLY BRAIN:Courtesy of Diane O'DowdO'Dowd's team measured neuronal activity from the central brain region, which is flanked on either side by the visual lobes and eyes (red).Drosophila, the winged workhorse of biology, has reached another milestone. Recently several labs have recorded electrophysiological data from the fly's central nervous system (CNS) neurons. "Drosophila is one of the most powerful neurobiological model systems around. The only thing it lacked was direct acce

Karen Heyman
Mar 14, 2004
<p>IMAGE OF AN ADULT FLY BRAIN:</p>

Courtesy of Diane O'Dowd

O'Dowd's team measured neuronal activity from the central brain region, which is flanked on either side by the visual lobes and eyes (red).

Drosophila, the winged workhorse of biology, has reached another milestone. Recently several labs have recorded electrophysiological data from the fly's central nervous system (CNS) neurons. "Drosophila is one of the most powerful neurobiological model systems around. The only thing it lacked was direct access to neurons of the CNS," says Leslie Griffith of Brandeis University, Waltham, Mass., where she has been recording from both larval and adult intact central nervous systems.1"I think that it was time for this technical barrier to fall."

Rachel Wilson and Glenn Turner, postdoctoral researchers in the lab of Gilles Laurent at California Institute of Technology, published a paper in Science based on their recordings in adult flies.2...

PICKING OUT BRAINS

Victor Huaiyu Gu, a microsurgeon in his native China and currently a postdoc in the laboratory of Drosophila CNS pioneer O'Dowd, uses surgical needles to open a fly's head. While his speed is impressive, what he puts on the slide is even more so: Floating in the saline is the brain that Gu has just removed – it's the size of a dust mote.

O'Dowd has moved on from her original work in cultured cells to record from whole brains surgically removed from adult flies.3 At the UCLA Learning and Memory Symposium in June of 2003, when she announced that she was recording from cells as small as 1.5 microns, there were audible gasps in the audience. But O'Dowd points to work in equally small mammalian dendrites as her own inspiration. "The size of individual neurons wasn't the barrier. Electrophysiologists overcame the technical limitations of recording from small cells 10 years before. The barrier was the size of the organism."

O'Dowd, who will detail her approach in an upcoming paper on synaptic transmission in memory mutants, says that her biggest challenge was to minimize disruption to the neurons. "We can now take the whole brain out and put it in a recording chamber, a preparation in between a slice and an intact animal," she says. With the connections between neurons largely intact, it is possible to assess synaptic transmission at the level of single cells in a functioning network.

Griffith adds that such work can be combined with functional genomics data to help researchers better understand Drosophila behavior. "We know an incredible amount about the genes and proteins that are used to control behavior in flies. Getting information about how neurons are functioning in intact circuits is going to provide powerful tools for taking behavior apart and understanding it in an integrated fashion," she says. "Hopefully this will also get the poor fly a bit more respect – vertebrate chauvinists beware!"

- Karen Heyman

Interested in reading more?

Become a Member of

Receive full access to digital editions of The Scientist, as well as TS Digest, feature stories, more than 35 years of archives, and much more!
Already a member?