Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sex discrimination in parasitoid wasps

16.06.2005


Dutch researcher Joke van Vugt investigated extremely selfish chromosomes which ensure only male offspring in two species of parasitoid wasps. She discovered that the discriminating chromosomes in the two species are not genetically similar, even though they have exactly the same effect.



Parasitoid wasps are haplodiploid. This means that the male wasps develop from unfertilised eggs and only have one set of chromosomes, namely those of their mother. Female wasps develop from fertilised eggs and have two sets of chromosomes: one from their mother and one from their father.

A special egoistic B chromosome is present in some males of the parasitoid wasp species Trichogramma kaykai and Nasonia vitripennis. Although this chromosome has the same effect and a similar structure in both wasps, Van Vugt demonstrated that both chromosomes do not share any DNA sequence homology. From this she concluded that both types of the chromosome have a different origin. Therefore the existence of more such B chromosomes in other insect species seems likely. This could also point to a simple molecular mechanism of these chromosomes which has developed more than once during the course of evolution.


More males due to selfish chromosome

The B chromosome ensures that only male offspring develop. In eggs fertilised with sperm from these males, the complete genome from the father is destroyed during the first nuclear division. However, the B chromosome remains intact and is incorporated into the chromosome set of the mother. Such fertilised eggs develop into males with the B chromosome. Accordingly this chromosome is only inherited from father to son.

This selfish chromosome is called the Paternal Sex Ratio (PSR) chromosome and was first discovered in N. vitripennis. At the end of 1997 a second PSR chromosome was discovered in the unrelated parasitoid wasp T. kaykai. This made a comparative study of PSR chromosomes possible.

PSR chromosomes can easily cross species boundaries and might therefore be useful for the control of insect pests, such as the Argentine ant. The introduction of these chromosomes would lead to increasingly less females developing. And without females such insect populations quickly perish.

Dr Joke J.F.A. van Vugt | alfa
Further information:
http://www.nwo.nl/nwohome.nsf/pages/NWOP_6CVFCV_Eng

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht 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

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

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...

Im Focus: Quantum Particles Form Droplets

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...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

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,...

Im Focus: Molecules change shape when wet

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...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>