A RhoGAP protein as a main immune suppressive factor in the Leptopilina boulardi (Hymenoptera, Figitidae)-Drosophila melanogaster interaction

Insect Biochem Mol Biol. 2005 Feb;35(2):93-103. doi: 10.1016/j.ibmb.2004.10.004.


To protect its eggs, the endoparasitoid wasp Leptopilina boulardi injects immune suppressive factors into Drosophila melanogaster host larvae. These factors are localized in the female long gland and reservoir. We analyzed the protein content of these tissues and found that it strongly differed between virulent and avirulent parasitoid strains. Four protein bands present in virulent long glands were eluted and their immune suppressive effect was assessed in vivo, allowing demonstrating a major effect of one of these proteins. The corresponding cDNA encodes a predicted 30 kDa subunit containing a Ras homologous GTPase Activating Protein (RhoGAP) domain, suggesting a possible involvement in the regulation of actin cytoskeleton changes. Using Western-blot experiments, we showed that this protein is abundant in virulent female long glands but is undetectable in virulent females deprived of long glands or in long glands from avirulent wasps. Its potential role in modifying the morphology and the adhesive properties of the host lamellocytes, involved in Drosophila cellular immune responses, is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Conserved Sequence
  • Drosophila melanogaster / immunology
  • Drosophila melanogaster / parasitology*
  • Female
  • GTPase-Activating Proteins / chemistry
  • GTPase-Activating Proteins / physiology*
  • Host-Parasite Interactions
  • Hymenoptera / chemistry
  • Hymenoptera / physiology*
  • Immune Tolerance
  • Insect Proteins / chemistry
  • Insect Proteins / physiology*
  • Larva / physiology
  • Molecular Sequence Data
  • Ovum
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Virulence / physiology


  • GTPase-Activating Proteins
  • Insect Proteins
  • rho GTPase-activating protein