How does a male moth find the right sort of female for mating, when there are two similar types luring him with their pheromones? In many species, differences in the antenna used by the male to smell these perfumes are responsible for his choice. But in the European Corn Borer, changes in the male's brain seem to dictate his choice between two types of available females, as shown by researchers from the University of Amsterdam, the Swedish University of Agricultural Sciences, and the Max Planck Institute for Chemical Ecology.
Female moths produce a sex pheromone, a different blend of chemicals for each species, which attracts males from a distance. Males detect these chemicals with exquisitely sensitive hair-like structures in the antenna. These hairs contain specialized neurons, nerve cells that express pheromone receptors which are activated when they bind to individual pheromone components.
Different species have different pheromone receptors, and so the ability to most accurately smell females of the same species prevents attraction to other females. Solving the puzzle of why a certain pheromone receptor is activated only by a specific chemical has motivated much past research.
"Our previous work in mapping the pheromone receptors of the European Corn Borer convinced us that this species doesn't fit the mold, and so we took another approach," says lead author Fotini Koutroumpa.
The European Corn Borer uses a simple pheromone with only two isomeric compounds, identical except for the orientation of a double bond. The two "pheromone strains" of this species produce them in different proportions. E-strain females make mostly the E isomer with traces of the Z isomer, which is highly attractive to E-strain males. Z-strain females release the opposite ratio, attracting Z-strain males.
In both cases, both components are absolutely necessary for attraction, and males of both strains can smell both, with similar or identical antennal structures and pheromone receptors. So what difference among the E and Z males could explain their opposite preferences? "We decided to look for a difference at the genetic level", says co-author Astrid Groot.
By crossing the E and Z strains in the laboratory and mapping the gene governing male preference, the researchers found that the pheromone receptors had little or no effect. Instead, a chromosomal region containing genes involved in neuronal development explained most of the male behavioral response. "This result fits with our previous work showing that E and Z males have different connections between the brain and the neurons containing pheromone receptors," explains co-author Teun Dekker.
This suggests that females of the E or Z strain smell the same to both E and Z males, while their preferences are controlled not by their noses but instead by their brains. "This result will point future research towards the tiny but complex moth brain, and shed light on how the diverse pheromone systems of the thousands of moth species has changed throughout evolution," concludes co-author David Heckel. [DGH]
Koutroumpa, F. A., Groot, A. T., Dekker, T., Heckel, D. G. (2016). Genetic mapping of male pheromone response in the European Corn Borer identifies candidate genes regulating neurogenesis. Proceedings of the National Academy of Sciences of the United States of America (Early Edition), DOI: 10.1073/pnas.1610515113
David G. Heckel, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07743 Jena, Germany, +49 3641 57 1500, firstname.lastname@example.org
Contact and Media Requests:
Angela Overmeyer M.A., Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07743 Jena, +49 3641 57-2110, E-Mail email@example.com
Download high-resolution images via http://www.ice.mpg.de/ext/downloads2016.html
Angela Overmeyer | Max-Planck-Institut für chemische Ökologie
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy