Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fighting like a girl or boy determined by gene in fruit flies

21.11.2006
Fighting like a girl or fighting like a boy is hardwired into fruit fly neurons, according to a study in the Nov. 19 Nature Neuroscience advance online publication by a research team from Harvard Medical School and the Institute of Molecular Pathology in Vienna.

The results confirm that a gene known as "fruitless" is a key factor underlying sexual differences in behavior. The findings mark a milestone in an unlikely new animal model for understanding the biology of aggression and how the nervous system gives rise to different behaviors.

"Aggression is a very serious problem in society, and it's a problem with a biological and genetic component," said co-author Edward Kravitz, the George Packer Berry professor of neurobiology at HMS, who developed the fruit fly fighting model used. "We want to understand that. I can't think of a better system to study than fruit flies. And no one gets hurt."

The fruitless gene is known for its role in male courtship. The large gene makes a set of male-specific proteins found exclusively in the nervous system of fruit flies, in about 2 percent of neurons. The proteins are necessary for normal courting. Males missing the proteins do not court females, and they sometimes court males, other research groups have shown. Females with a male version of the gene perform the male courting ritual with other females.

The same gene directs another sex-specific behavior – fighting patterns, the new study shows. Female fighting, for example, largely involves head butts and some shoving. Males prefer lunges; they rear up on their back legs and snap their forelegs down hard – sometimes nailing an opponent that is slow to retreat.

The flies undergo a major role reversal when the male and female gene versions are switched. With a feminine fruitless gene, male flies adopt more ladylike tactics, mostly the head butt and some shoving. With the masculine fruitless gene, females instinctively lunge to the exclusion of their usual maneuvers.

The gender-bending fruit flies were first developed to study courtship in the Austrian lab of co-author Barry Dickson, director of the Institute of Molecular Pathology. Dickson created male flies with the female version of the gene and female flies with the male version.

In Dickson's courtship studies, male fruit flies with the female fruitless gene were not acting like males, but it wasn't clear that they were acting like females, either. (Ultimately, courtship behavior is constrained by pheromones and anatomy, which do not change.) He contacted Kravitz, hoping that aggression studies would resolve the lingering question of male behavior changes.

Meanwhile, co-author Steven Nilsen, a postdoctoral fellow in Kravitz's lab, had similar questions and was staging contests between another line of mutant fruitless flies without such clear brain-switching genetics. So Austrian postdoctoral fellow Eleftheria Vrontou, the lead author, packed up their flies and took them to the Boston fruit fly fight club.

For the past five years, researchers in Kravitz's lab have been methodically scoring fruit fly fights to determine the normal aggression patterns with the long-term goal of documenting how genes and molecules change those patterns. They stage male fights on bottle-cap-sized food cups decorated with a headless female (a live female will fly away, leaving males nothing to fight over). Female flies fight over an extra dab of fresh yeast paste – their version of dark chocolate, Kravitz said. The flies are videotaped. The movies are replayed in slow motion to record each move and countermove.

"Ed has systematically developed reproducibly aggressive behavior in flies and paved the way for serious analysis," said Laurie Tompkins, program director at the National Institute of General Medical Sciences, which funds the work. The fruit fly aggression model is part of a new trend to use fruit flies as models to study complex behaviors, including sleep and responses to painful stimuli, Tompkins said. "Drosophila have marvelous advantages in terms of genetic tricks," she said, "and flies in many respects behave and respond similarly to humans."

The findings provide a welcome guidepost to help enable future research to track down the underlying neural circuitry, said Bruce Baker, a biology professor at Stanford who first linked the fruitless gene to male-specific courtship behavior. "That's a pretty big thing," Baker said. "We can think about understanding in molecular detail how we go from the initial genes and the proteins they encode to the nervous system that causes our body to respond in certain ways." More generally, he said, such studies form a potential bridge between systems neuroscience studies of behavior and modern molecular neuroscience research into individual neurons and synapses.

John Lacey | EurekAlert!
Further information:
http://www.hms.harvard.edu

Further reports about: Aggression behavior courtship fruit flies proteins studies

More articles from Life Sciences:

nachricht Study shines light on brain cells that coordinate movement
26.06.2017 | University of Washington Health Sciences/UW Medicine

nachricht New insight into a central biological dogma on ion transport
26.06.2017 | Aarhus University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>