1887

Abstract

Lamellocytes are specialized larval blood cells of that carry out encapsulation of metazoan pathogens such as parasitoid wasps. Large virus-like particles (VLPs) from two closely related virulent parasitoid wasp species, and , suppress the host encapsulation response by promoting lysis of lamellocytes. The molecular basis of VLP–lamellocyte interaction and lamellocyte lysis is not understood. Here, it was shown that mature VLPs are composed of at least four major proteins. Polyclonal antisera against the most abundant VLP protein, p40, cross-reacted with the most abundant VLP protein, p47.5. Immuno-electron microscopy (EM) of the long gland–reservoir complex revealed that p40 was expressed early in VLP biogenesis and was detected along with VLP precursors within the long gland cells and lumen. In the reservoir, VLPs had an angular core, resembled mature particles and p40 was detected outside the VLP cores. Immuno-EM staining of mature VLPs from both species localized the p40 and p47.5 proteins largely to the periphery of the VLPs and along the VLP spike-like projections. p40 staining was observed in VLP-treated host haemocytes. , anti-p40 antibody almost completely blocked the ability of VLPs to promote lamellocyte lysis. Anti-p40 antibody blocked lysis by VLPs by >50 %. It is proposed that the VLP surface proteins p40 and p47.5 share antigenic determinants and significantly contribute to the strong virulence of their Hymenopteran hosts.

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2006-02-01
2019-11-21
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References

  1. Ashburner, M. ( 1989; ). Drosophila. A Laboratory Handbook. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
  2. Bodian, D. L., Leung, S., Chiu, H. & Govind, S. ( 2004; ). Cytokines in Drosophila hematopoiesis and cellular immunity. Prog Mol Subcell Biol 34, 27–46.
    [Google Scholar]
  3. Bradford, M. M. ( 1976; ). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein–dye binding. Anal Biochem 72, 248–254.[CrossRef]
    [Google Scholar]
  4. Brennan, C. A. & Anderson, K. V. ( 2004; ). Drosophila: the genetics of innate immune recognition and response. Annu Rev Immunol 22, 457–483.[CrossRef]
    [Google Scholar]
  5. Carton, Y. & Nappi, A. J. ( 1997; ). Drosophila cellular immunity against parasitoids. Parasitol Today 13, 218–227.[CrossRef]
    [Google Scholar]
  6. Chiu, H. & Govind, S. ( 2002; ). Natural infection of D. melanogaster by virulent parasitic wasps induces apoptotic depletion of hematopoietic precursors. Cell Death Differ 9, 1379–1381.[CrossRef]
    [Google Scholar]
  7. Dawson, B. & Trapp, R. G. ( 2004; ). Basic and Clinical Biostatistics, 4th edn. New York: McGraw Hill.
  8. Dupas, S., Brehelin, M., Frey, F. & Carton, Y. ( 1996; ). Immune suppressive virus-like particles in a Drosophila parasitoid: significance of their intraspecific morphological variations. Parasitology 113, 207–212.[CrossRef]
    [Google Scholar]
  9. Hanratty, W. P. & Dearolf, C. R. ( 1993; ). The Drosophila Tumorous-lethal hematopoietic oncogene is a dominant mutation in the hopscotch locus. Mol Gen Genet 238, 33–37.
    [Google Scholar]
  10. Labrosse, C., Carton, Y., Dubuffet A., Drezen, J. M. & Poirie, M. ( 2003; ). Active suppression of D. melanogaster immune response by long gland products of the parasitic wasp Leptopilina boulardi. J Insect Physiol 49, 513–522.[CrossRef]
    [Google Scholar]
  11. Laemmli, U. K. ( 1970; ). Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227, 680–685.[CrossRef]
    [Google Scholar]
  12. Lanot, R., Zachary, D., Holder, F. & Meister, M. ( 2001; ). Postembryonic hematopoiesis in Drosophila. Dev Biol 230, 243–257.[CrossRef]
    [Google Scholar]
  13. Merril, C. R., Goldman, D., Sedman, S. A. & Ebert, M. H. ( 1981; ). Ultrasensitive stain for proteins in polyacrylamide gels shows regional variation in cerebrospinal fluid proteins. Science 211, 1437–1438.[CrossRef]
    [Google Scholar]
  14. Morales, J. ( 2005; ). Immune suppression by parasitoid wasps of Drosophila: studies on virus-like particles, virulence, and genome-wide expression analysis. PhD thesis, The City University of New York, USA.
  15. Morales, J., Chiu, H., Oo, T., Plaza, R., Hoskins, S. & Govind, S. ( 2005; ). Biogenesis, structure, and immune suppressive effects of virus-like particles of a Drosophila parasitoid, Leptopilina victoriae. J Insect Physiol 51, 181–195.[CrossRef]
    [Google Scholar]
  16. Newman, G. R., Jasani, B. & Williams, E. D. ( 1982; ). The preservation of ultrastructure and antigenicity. J Microsc 127, RP5–RP6.
    [Google Scholar]
  17. Rizki, T. M. & Rizki, R. M. ( 1984a; ). The cellular defense system of Drosophila melanogaster. In Insect Ultrastructure, vol. 2, pp. 579–604. Edited R. C. King & H. Akai. New York: Plenum.
  18. Rizki, R. M. & Rizki, T. M. ( 1984b; ). Selective destruction of a host blood cell type by a parasitoid wasp. Proc Natl Acad Sci U S A 81, 6154–6158.[CrossRef]
    [Google Scholar]
  19. Rizki, R. M. & Rizki, T. M. ( 1990; ). Parasitoid virus-like particles destroy Drosophila cellular immunity. Proc Natl Acad Sci U S A 87, 8388–8392.[CrossRef]
    [Google Scholar]
  20. Rizki, T. M. & Rizki, R. M. ( 1994; ). Parasitoid-induced cellular immune deficiency in Drosophila. Ann N Y Acad Sci 712, 178–194.[CrossRef]
    [Google Scholar]
  21. Russo, J., Dupas, S., Frey, F., Carton, Y. & Brehelin, M. ( 1996; ). Insect immunity: early events in the encapsulation process of parasitoid (Leptopilina boulardi) eggs in resistant and susceptible strains of Drosophila. Parasitology 112, 135–142.[CrossRef]
    [Google Scholar]
  22. Sambrook, J., Fritsch, E. F. & Maniatis, T. ( 1989; ). Molecular Cloning: a Laboratory Manual. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
  23. Schilthuizen, M., Nordlander, G., Stouthamer, R. & van Alphen, J. J. M. ( 1998; ). Morphological and molecular phylogenetics in the genus Leptopilina (Hymenoptera: Cynipoidea: Eucoilidae). Syst Entomol 23, 253–264.[CrossRef]
    [Google Scholar]
  24. Schmidt, O., Theopold, U. & Strand, M. ( 2001; ). Innate immunity and its evasion and suppression by hymenopteran endoparasitoids. Bioessays 23, 344–351.[CrossRef]
    [Google Scholar]
  25. Sorrentino, R. P., Carton, Y. & Govind, S. ( 2002; ). Cellular immune response to parasite infection in the Drosophila lymph gland is developmentally regulated. Dev Biol 243, 65–80.[CrossRef]
    [Google Scholar]
  26. Vass, E. & Nappi, A. J. ( 2000; ). Developmental and immunological aspects of Drosophila–parasitoid relationships. J Parasitol 86, 1259–1270.
    [Google Scholar]
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