Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fruit Fly Pheromone Receptor First Ever Discovered Linked to Specific Sexual Behavior

11.09.2003


Hubert Amrein, Ph.D., Assistant professor of genetics and microbiology


For the first time in any animal, Duke University Medical Center researchers have linked a single pheromone receptor in the fruit fly to a specific sexual behavior.

Pheromones are chemical signals exuded by many animals -- including humans -- that serve as stimuli to evoke behavioral responses in other individuals of the same species. Pheromones often attract members of the opposite sex and provide important cues during courtship and mating.

Yet little is known about pheromone receptors, which are the protein switches nestled in cell membranes that trigger responses to pheromones, said Duke Medical Center geneticist Hubert Amrein, Ph.D., senior author of the study.



Now, he and co-author Steven Bray, also of Duke, report that male Drosophila fruit flies lacking one type of taste receptor have difficulty recognizing females. Although the males initiate the courtship ritual, the flies’ mating dance stalls when they apparently fail to detect the proper chemical cue from females. The sexually aberrant flies otherwise behaved normally, the researchers report in the Sept. 11, 2003, issue of Neuron.

"Scientists have been chasing pheromone receptors in animals for a long time with little success," Amrein said, noting that although putative receptors have been found, tying those to specific behaviors had remained a major challenge. "Now, we have identified a receptor and a very specific aspect of courtship for which it is required."

The work was funded by a grant from the National Institutes of Health.

Like mammals, insects display complex mating behaviors, many of which are triggered automatically in response to pheromones or other stimuli, Amrein said. Although the same principles likely underlie the behavior in all animals, he added, flies’ simpler nervous system makes them an ideal model for study.

Courtship in Drosophila includes a regular sequence of behaviors, which are critical for mating, Amrein explained. First, a male identifies a female visually. The male then approaches the female and touches her with his forelegs -- which contain one of the flies’ taste organs -- in a behavior known as tapping. After detecting pheromones from the female, the male produces a courtship song through rapid wing vibrations. The receptive female slows, allowing the male to investigate further with his labellum, the fly equivalent of a tongue. Finally, the male fly begins bending its abdomen as required for copulation, and the two mate.

In their search for pheromone receptor genes, the researchers explored the location of some 25 of 70 known taste receptors on the fly’s body. They found that one such candidate pheromone receptor, encoded by a gene called Gr68a, showed up only on the forelegs that males use in the tapping stage of courtship. Also, found the researchers, the activity of the Gr68a gene was governed by a gene that controls many aspects of sexual differentiation in flies.

The researchers found that male flies lacking the neurons that express the Gr68a receptor spent less time courting females and, as a result, mated significantly less often than normal flies did. Those deficient flies that did mate successfully took twice as long to do so in comparison to intact males.

Also, found the researchers, males lacking the Gr68a-expressing neurons initiated courtship more often than normal but the ritual stalled after the tapping stage, when males apparently failed to receive the pheromone cue from females. Flies lacking only Gr68a showed the same dysfunction as those lacking the neurons completely, a result which links the behavior directly to the taste receptor, Amrein said.

"It’s quite remarkable that a single gene receptor, expressed in just a few cells of the entire male fly, plays such a crucial role in the courtship process," Amrein said. "When you knock out the function of the gene, the flies show a serious mating deficit."

Although an earlier study found that mice lacking 16 genes thought to include pheromone receptors exhibited abnormal sexual and aggressive behavior, this is the first study to clearly link a single pheromone receptor to a specific mating behavior, Amrein said.

Besides chemical sensing, courtship in flies involves visual and auditory cues. Therefore, Amrein said, the finding in fruit flies is a step toward understanding how the brain integrates different kinds of sensory input and translates those signals into complex behaviors critical to reproduction and survival.

Kendall Morgan | Duke Med News
Further information:
http://dukemednews.org/news/article.php?id=7022

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>