Researchers at the Institute of Molecular Pathology (IMP) in Vienna present novel method to study the activity of specific brain regions in moving flies.
In a joint effort with collaboration partners from the Vienna University of Technology and a lab in the USA, the team of Andrew Straw at the IMP developed a special device for the thermogenetic control of flies. This tool, called FlyMAD, enabled the scientists to target light or heat to specific body regions of flies in motion and to analyse the animals‘ brain cells. Compared to other techniques, FlyMAD allows highly improved temporal resolution. Using the new technology, Straw and his colleagues got new insight into the role of two neuronal cell types in courtship behavior of flies. The results of the study will be published online in Nature Methods on May 25 (doi 10.1038/nmeth.2973).
This composite image shows a laser being aimed at a walking fly using the FlyMAD system.
Matt Staley and Dan Bath, JFRC, HHMI
A male Drosophila raises a wing and ‘sings’ due to neuronal activation of song neurons.
Dan Bath, JFRC, HHMI
The fruit fly Drosophila Melanogaster represents an ideal experimental system to analyse circuit functions of brain cells (neurons). In the past, it was not possible to specifically control the activity of neurons in moving flies. Andrew Straw and his team have now overcome this barrier.
Rapid mind alteration in moving flies
Straw and his co-workers are interested in the mechanisms underlying cell circuits in the fly brain. Straw’s group concentrates on the control of complex behaviors such as courtship. In order to better understand how different neuronal circuits work together, Straw and his team developed FlyMAD (“Fly Mind Altering Device”), an apparatus using a video camera to track the flies‘ motion in a box. FlyMAD allows simultaneous observation of several flies and targeted irradiation of specific body regions of these animals. By combining the sensitive methods of optogenetics and thermogenetics, the researchers were able to specifically alter neural pathways in the fly brain with FlyMAD.
The novel technology of thermogenetics uses genetically modified, temperature-sensitive flies. Upon irradiation with infrared light and the concomitant rise in temperature to 30 degrees Celsius, these animals change certain aspects of their behavior. This does not happen at a control temperature of 24 degrees Celsius. Compared to other commonly used methods, FlyMAD applies a highly improved temporal resolution. Infrared-induced activation or repression of specific neurons and the following change in the animals‘ behavior occur within the fraction of a second.
The application of visible light to certain genetically engineered flies can also induce alterations of their brain. FlyMAD thus represents an absolute novelty for fly research, as optogenetics has been restricted to mice so far.
New insight into courtship behavior of flies
Straw and his co-workers tested FlyMAD by analyzing already known reactions of genetically modified flies to light and heat. As this proof-of-principle showed that FlyMAD worked reliably – for example by making the flies “moonwalk” - the researchers went on to use their method to tackle new scientific questions. In a thermogenetic set up, they investigated a certain type of neurons that had been linked to the flies’ courtship song in earlier experiments. Taking advantage of the better temporal resolution of FlyMAD, the scientists were able to characterize the role of two neuronal cell types in the brain in more detail. They could show that activity of one type of neurons correlated with a persistent state of courtship, whereas the other cell type was important for the action of “singing”. In the experiment this became obvious when males tried to mate with a ball of wax, circled it and started vibrating their wings after stimulation with the laser beam.
FlyMAD allows combination of optogenetics and thermogenetics
In the future, Straw wants to combine the activation of flies both by light and by heat in one experiment – that is feasible with FlyMAD. This would allow the activation or repression of different genetic elements in one fly. „FlyMAD offers the fantastic opportunity to address many of our questions. We could, for example, analyze how single neurons function in a cascade within the neuronal circuit“, Straw emphasizes the potential of his work. Ultimately, new insight into the function of the fly brain can also be applied to the network of cells in the mammalian brain.
Daniel E. Bath, John R. Stowers, Dorothea Hörmann, Andreas Poehlmann, Barry J. Dickson and Andrew D. Straw. FlyMAD: Rapid thermogenetic control of neuronal activity in freely-walking Drosophila. Nature Methods, doi 10.1038/nmeth.2973, 2014
This work was funded by a postgraduate scholarship from Canada, an ERC starting grant, a WWTF grant, an ERC Advanced Grant and by IMP core funding.
Illustrations to be used free of charge in connection with this press release can be downloaded from the IMP website: www.imp.ac.at/pressefoto-flymad
About Andrew Straw
Andrew Straw studied biology in Los Angeles, USA, and obtained his PhD in Adelaide in 2004 for his dissertation in the field of neurobiology. He worked as a Postdoc and Senior Postdoc at Caltech in Pasadena, USA, and became Senior Research Fellow there in 2010. Since 2010, Straw holds a position as Research Fellow at the IMP in Vienna where he has his own independent research group. His work is partly funded by an ERC Starting grant.
About the IMP
The Research Institute of Molecular Pathology (IMP) in Vienna is a basic biomedical research institute largely sponsored by Boehringer Ingelheim. With over 200 scientists from 37 nations, the IMP is committed to scientific discovery of fundamental molecular and cellular mechanisms underlying complex biological phenomena. Research areas include cell and molecular biology, neurobiology, disease mechanisms and computational biology.
Andrew Straw, PhD
Dr. Heidemarie Hurtl
Phone: +43 (0)664 8247910
Mag. Evelyn Devuyst, MAS
Phone: +43 1 79044 3626
Phone: +43 1 79730 3824
Dr. Heidemarie Hurtl | idw - Informationsdienst Wissenschaft
MACC1 Gene Is an Independent Prognostic Biomarker for Survival in Klatskin Tumor Patients
31.08.2015 | Max-Delbrück-Centrum für Molekulare Medizin in der Helmholtz-Gemeinschaft
Fish Oil-Diet Benefits May be Mediated by Gut Microbes
28.08.2015 | University of Gothenburg
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.
These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...
Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.
For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
31.08.2015 | Awards Funding
31.08.2015 | Materials Sciences
31.08.2015 | Materials Sciences