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 A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>