Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie

Purpose

Shelf life

CAS and PHP session cookies

Login credentials, session security

Session

Tarteaucitron

Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie

Purpose

Shelf life

atid

Trace the visitor's route in order to establish visit statistics.

13 months

atuserid

Store the anonymous ID of the visitor who starts the first time he visits the site

13 months

atidvisitor

Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at cil-dpo@inrae.fr or by post at :

INRAE

24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu INRAE LOGO_MUSE

Home page

In parallel, we are also interested in the diversity of virus-ichneumonid wasp associations

Below are two examples of our work illustrating this diversity ...
Identification of an ichnoviral machinery in a beetle parasitoid producing atypical particles

In the literature, ichnoviruses are described as being associated with parasitoids of lepidopteran larvae. Species of the genus Bathyplectes, which are campoplegine ichneumonids that parasitize larvae of the alfalfa pest Hypera postica (Coleoptera: Curculionidae), also produce virus particles in their ovaries. However, these particles are atypical compared to classical ichnovirus particles (Figure 4). This raised the question of their nature.

Figure 4

Figure 4. Electron microscopic view of virus particles produced in Bathyplectes sp. (diam. ~200 nm) and Hyposoter sp. (length ~300 nm). Figure taken from the team's publication DOI: 10.1016/j.virusres.2019.02.001.

To find out the nature of these atypical particles, the transcriptome of Bathyplectes anurus ovaries was analyzed (Robin et al, 2019). We were able to identify a total of 28 homologs to genes of the ichnoviral machinery, as well as a few sequences corresponding to genes of the repeat element family, characteristic of the segments encapsidated in the ichnovirus particles of campoplegines. The atypical particles of this parasitoid are therefore related to ichnoviruses.

This work shows the diversity of particles that can be produced by the machinery that derives a priori from a single event of integration of an ancestor viral genome.

Loss of ichnovirus and exaptation of a nudivirus in the lineage of the parasitoid Venturia canescens

Venturia canescens is a campoplegine that parasites stored food pests (e.g. Ephestia kuehniella). This species, although phylogenetically close to ichnovirus-associated species, produces DNA-free particles called virus-like particles (VLPs) (Figure 5). VLPs mainly contain proteins encoded by wasp genes. They associate with the eggs in the lumen of the oviducts and protect the eggs from destruction by the host immune system. Our work has shown that VLPs are derived from the incorporation of an alphanudivirus genome (Pichon et al, 2015). The analysis of the wasp genome also identified deeply reshuffled ichnovirus sequences. This indicates that the ancestor of this wasp was indeed associated with an ichnovirus and that the incorporation of the nudivirus resulted in a viral symbiont replacement. This is the first described example of the replacement of an endogenous virus playing a functional role in the life cycle of the organism that hosts it.

Figure 5

Figure 5. Electron microscopic view of VLPs produced in Venturia canescens. Figure taken from the team's publication DOI: 10.1051/medsci/20163208013.

The V. canescens genome contains 51 functional nudiviral genes, including many nudivirus core genes but no genes encoding capsid proteins or involved in viral DNA packaging, which is consistent with the absence of DNA in VLPs. Further analysis of the V. canescens genome revealed that the genes involved in viral DNA replication and packaging are present as pseudogenes (Leobold et al 2018). This supports the hypothesis that an entire nudivirus genome was initially integrated into a wasp chromosome.

Bracoviruses, the other PDV genus, also derive from the integration of a nudivirus, but different from the one at the origin of VLPs. Thus, our work shows that two independent events of capture of nudivirus genomes in two lineages of parasitoid wasps have led to two modalities of evolution of endogenous viral sequences that result in different strategies of control of host physiology, since bracoviruses allow the transfer of genes whereas VLPs the transfer of proteins towards the parasitoid host.