Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-26T17:02:51.778Z Has data issue: false hasContentIssue false
  • English
  • Français

Immune suppressive virus-like particles in a Drosophila parasitoid: significance of their intraspecific morphological variations

Published online by Cambridge University Press:  06 April 2009

S. Dupas ,
M. Brehelin ,
F. Frey  and
Y. Carton
S. Dupas*
Affiliation:
Laboratoire Populations, Genetique et Evolution, CNRS 91198 Gif-sur-Yvette CEDEX, France
M. Brehelin
Affiliation:
INRA-CNRS URA 1184, Pl E. Bataillon, 34095 Montpellier, France
F. Frey
Affiliation:
Laboratoire Populations, Genetique et Evolution, CNRS 91198 Gif-sur-Yvette CEDEX, France
Y. Carton
Affiliation:
Laboratoire Populations, Genetique et Evolution, CNRS 91198 Gif-sur-Yvette CEDEX, France
*
* Corresponding author. Tel: 69823714. Fax: 69824448. E-mail: [email protected].
Get access Rights & Permissions [Opens in a new window]

Summary

The Eucoilid parasitoid Leptopilina boulardi is able to suppress its host Drosophila melanogaster immune reaction. Some strains, however, are non-immune suppressive to that host. Virus-like particles (VLPs) responsible for the immune suppressive ability were investigated in different strains of L, boulardi with histochemical and ultrastructural techniques. Membrane-bound particles containing vesicles were observed in the reservoir of the long gland and also in the egg canal of the ovipositor. These particles are homologous with the immune suppressive VLPs already described in the reservoir of L. heterotoma. Similarities were also observed with the L2 particles described previously around the chorion of the parasitoid egg after infestation. A weak positive DNA specific histochemical reaction was observed inside the reservoir and at the ultrastructural level. Feulgen-derived techniques demonstrated that the reaction was localized inside the particles. The morphology of the particles as well as the immune suppressive ability varied between strains. Two morphotypes of VLPs are described; the ‘Is’ morphotype (always observed in immune suppressive or Is strains) and the ‘NIs’ morphotype (observed in the non-immune suppressive or NIs strain). The hybrids between Is and NIs strains produce a third type of particle, the ‘His’morphotype with half-immune suppressive ability and intermediate morphology. The origin of the particles' immune suppressive activity against D. melanogaster is discussed within the scope of host specificity.

Keywords

Leptopilina boulardivirus-like particlesimmune suppressive abilityintraspecific variability
Type
Research Article
Information
Parasitology , Volume 113 , Issue 3 , September 1996 , pp. 207 - 212
Copyright
Copyright © Cambridge University Press 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Ashburner, M. (1989). Drosophila, a Laboratory Manual. Cold Spring Harbor Laboratory Press, New York.Google Scholar
Carton, Y. & Kitano, H. (1981). Evolutionary relationships to parasitism by seven species of the Drosophila melanogaster subgroup. Biological Journal of the Linnean Society 16, 350–362.CrossRefGoogle Scholar
Carton, Y., Frey, F. & Nappi, A. (1992). Genetic determinism of the cellular immune reaction in Drosophila melanogaster. Heredity 69, 393–399.CrossRefGoogle ScholarPubMed
Edson, K. M., Vinson, S. B., Stoltz, D. B. & Summers, M. D. (1981). Virus in a parasitoid wasp: suppression of the cellular immune response in the parasitoid's host. Science 211, 582–583.CrossRefGoogle Scholar
Federici, B. A. (1991). Viewing polydnaviruses as gene vectors of endoparasitic hymenoptera. Redia 74, 387–392.Google Scholar
Martoja, R. & Martoja-Pierson, M. (1967). Initiation aux Techniques de l'Histologie Animale. Massen: Paris.Google Scholar
Moyne, G. (1973). Feulgen-derived techniques for electron microscopical cytochemistry of DNA. Journal of Ultratructural Research 45, 102–123.CrossRefGoogle ScholarPubMed
Ratcliffe, N. A. & King, P. E. (1967). The venom system of Nasonia vitripenis (Walker) (Hymenoptera: Pteromalidae). Proceedings of the Royal Entomological Society of London, A 42, 49–61.CrossRefGoogle Scholar
Rizki, R. M. & Rizki, T. M. (1990). Parasitoid virus-like particles destroy Drosophila cellular immunity. Proceedings of the National Academy of Sciences, USA 87, 8388–8392.CrossRefGoogle ScholarPubMed
Russo, J., Dupas, S., Frey, F., Carton, Y. & Brehelin, M. (1996). Insect immunity: early events in encapsulation process of parasitoid (Leptopilina boulardi) eggs in reactive and non-reactive strain of Drosophila. Parasitology 112, 135–142.CrossRefGoogle Scholar
Stoltz, D. B. (1994). The polydnavirus life-cycle. In Parasites and Pathogens of Insects, Vol. 2. (ed. Beckage, N. E., Thompson, S. N. & Federici, B. A.), pp. 167–187. Academic Press, San Diego.Google Scholar
Stoltz, D. B. & Whitfield, J. B. (1992). Viruses and virus-like entities in the parasitic hymenoptera. Journal of Hymenopteran Research 1, 125–139.Google Scholar
Stoltz, D. B. & xu, D. (1990). Polymorphism in polydnavirus genome. Canadian Journal of Microbiology 36, 538–543.CrossRefGoogle Scholar