Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Parasite wasps have practiced gene therapy for a hundred million years

18.02.2009
Braconid parasite wasps and their caterpillar hosts form a unique host-parasite model: the wasps lay their eggs inside the caterpillars and simultaneously inject some viral particles to get around the host's defenses and control its physiology.

The genes from these viral particles have now been identified in the wasp's own genome by a team at the Institut de recherche sur la biologie de l'insecte (CNRS/Université François-Rabelais Tours), in collaboration with a laboratory at University of Berne and Genoscope d'Evry.

These genes came from a virus captured by a common ancestor of these wasps 100 million years ago. These results, published in Science 13 February 2009, could provide new means of designing transfer vectors for gene therapy.

Wasps of the family Braconidae reproduce by laying their eggs in caterpillars, which then serve as food for the developing wasp larvae (1). However, the body of a caterpillar is a hostile environment, with an efficient defense system that forms a capsule of immune cells around foreign objects. To get around these defenses, when the wasp lays her eggs in the caterpillar, she also injects some special particles made in her ovaries. These particles enter the caterpillar's cells where they induce immunosuppression and control development, allowing the wasp larvae to survive.

Although many examples of symbiotic bacteria are known, the present case of a parasitic species using a virus to control its host's physiology is unique. To improve our understanding of the phenomenon, researchers at the Institut de recherche sur la biologie de l'insecte (CNRS/Université François-Rabelais Tours) are studying these viral particles in detail. In previous work, they had questioned whether the particles were truly viral, as they found that the particle genome lacked the necessary machinery for replication usually found in viruses.

Their most recent findings, published in Science, show that the particles are indeed viral in nature, but that their components lie within the wasp's own genome. More that twenty different genes coding for characteristic components of nudiviruses - insect viruses often used in biological pest control - are expressed in the wasps' ovaries. Furthermore, these genes are conserved in the different kinds of wasp that make these particles.

The results indicate that the ancestor of the braconid wasps integrated the genome of a nudivirus into its own genome. Although these genes continue to produce viral particles, the particles now deliver the wasp's own virulence genes into the parasitized host.

The wasps have therefore "domesticated" a virus to turn it into a vector for transferring their genes. Study of this phenomenon is particularly interesting for the development of new vectors for gene therapy, a therapeutic technique that consists of inserting genes into an individual's cells or tissues to treat an illness. Genes are delivered using a deactivated virus as a vector. The particles from parasite wasps are in fact true "natural" vectors, selected over 100 million years to perform this function and capable of transferring large quantities of genetic material (more than 150 genes). Understanding how they work could therefore be very useful for the design of new therapeutic vectors.

(1) The wasp pierces the caterpillar's skin with a sort of stylet, called an auger. It then lays its eggs inside the body, and the wasp larvae then develop in the caterpillar's blood, on which they feed

Julien Guillaume | alfa
Further information:
http://www.cnrs.fr

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 >>>