CONTACT: GARY GALLUZZO
100 Old Public Library
Iowa City IA 52242
(319) 384-0009; fax (319) 384-0024
Release: Feb. 7, 2000
UI researcher studies love song of fruit fly
IOWA CITY, Iowa -- Dan Eberl is always on the lookout for love songs, but
not the kind played on the radio or in a Las Vegas lounge act.
That's because Eberl, a University of Iowa biology professor, is interested
in a very special kind of song -- the "love song" of the fruit fly.
Although it may seem an odd choice, the fruit fly and its love song are
very effective tools for learning about the molecular and cellular mechanisms
involved in hearing in other insects and in animals. In fact, says Eberl in
an article published in a recent issue of the journal Current Opinion in Neurobiology,
studying the fruit fly may one day help scientists to better understand human
Funded by a three-year, $225,000 grant from the Whitehall Foundation, Eberl
is trying to identify the genes involved in the various molecular processes
that enable fruit flies to hear their love song.
"My job is to identify the genes responsible for hearing in fruit flies.
The whole field of identifying genes related to deafness and hearing has blossomed
in the last five years," says Eberl, who spent one year at SUNY, Stony
Brook and five years at Harvard Medical School before coming to the UI last
year. "Fruit flies use antennas for hearing. The cells that detect the
antennal vibrations appear to share molecular mechanisms with bristles used
for the sense of touch. The receptors for hearing in vertebrates (including
humans) are structurally halfway between the two types. This means that insect
hearing may be related to human hearing."
The fruit fly love song plays a pivotal role in helping Eberl separate fruit
flies into two groups -- hearing and non-hearing -- so that he can compare
and contrast the genes responsible for hearing. It begins with the fruit fly
courting ritual. The male extends one wing and vibrates it in such a way as
to create the love song. Most females and males hear the song and respond
in a sex-specific manner, however some flies fail to respond and are thought
to be deaf. Eberl implants electrodes into the antennas of the unresponsive
flies, as well as a group of normal flies, and records the voltages the receptor
cells generate as the flies listen to the love song. By comparing the electrical
impulses generated by the normal flies to those generated by unresponsive
flies that are believed to be deaf, Eberl is able to distinguish the truly
deaf flies from those who may be able to hear but for some other reason fail
Within this group of truly deaf fruit flies, Eberl found several mutants
lacking genes needed to hear the love song. For example, he identified one
fly strain, nicknamed Beethoven, having a genetic mutation that disrupts the
structure and function of the hearing organ in the fruit fly antenna.
"Identifying the gene product of Beethoven and other such genes and
examining their functional roles in hearing will provide new insights into
auditory mechanisms, not only in fruit flies, but perhaps in humans, as well,"