title: Comparative venomics of Psyttalia lounsburyi and P. concolor, two olive fruit fly parasitoids: a hypothetical role for a GH1 β-glucosidase.
abstract: Venom composition of parasitoid wasps attracts increasing interest - notably molecules ensuring parasitism success on arthropod pests - but its variation within and among taxa is not yet understood. We have identified here the main venom proteins of two braconid wasps, Psyttalia lounsburyi (two strains from South Africa and Kenya) and P. concolor, olive fruit fly parasitoids that differ in host range. Among the shared abundant proteins, we found a GH1 β-glucosidase and a family of leucine-rich repeat (LRR) proteins. Olive is extremely rich in glycoside compounds that are hydrolyzed by β-glucosidases into defensive toxic products in response to phytophagous insect attacks. Assuming that Psyttalia host larvae sequester ingested glycosides, the injected venom GH1 β-glucosidase could induce the release of toxic compounds, thus participating in parasitism success by weakening the host. Venom LRR proteins are similar to truncated Toll-like receptors and may possibly scavenge the host immunity. The abundance of one of these LRR proteins in the venom of only one of the two P. lounsburyi strains evidences intraspecific variation in venom composition. Altogether, venom intra- and inter-specific variation in Psyttalia spp. were much lower than previously reported in the Leptopilina genus (Figitidae), suggesting it might depend upon the parasitoid taxa.
authors: Université Côte d'Azur, INRA, CNRS, ISA, France.
authors: Hugo
authors: H
authors: Mathé-Hubert
authors: Université Côte d'Azur, INRA, CNRS, ISA, France.
authors: Dominique
authors: D
authors: Colinet
authors: Université Côte d'Azur, INRA, CNRS, ISA, France.
authors: Emeline
authors: E
authors: Deleury
authors: CNRS, Aix-Marseille Université, UMR 7286, CRN2M, Centre d'Analyses Protéomiques de Marseille (CAPM), Faculté de Médecine, Marseille, France.
authors: Maya
authors: M
authors: Belghazi
authors: INRA, Univ. Montpellier, UMR 1333 « Microorganism &Insect Diversity, Genomes &Interactions » (DGIMI), CC101, Montpellier Cedex 34095, France.
authors: Marc
authors: M
authors: Ravallec
authors: Commissariat à l'Energie Atomique (CEA), Institut de Génomique (IG), Génoscope, 91000, Evry, France.
authors: Julie
authors: J
authors: Poulain
authors: Commissariat à l'Energie Atomique (CEA), Institut de Génomique (IG), Génoscope, 91000, Evry, France.
authors: Carole
authors: C
authors: Dossat
authors: Université Côte d'Azur, INRA, CNRS, ISA, France.
authors: Marylène
authors: M
authors: Poirié
authors: Université Côte d'Azur, INRA, CNRS, ISA, France.
authors: Jean-Luc
authors: JL
authors: Gatti
mesh_terms: D000818:Animals; D019476:Insect Proteins / Q000032:analysis*; D007630:Kenya; D000090263:Leucine-Rich Repeat Proteins; D011506:Proteins / Q000032:analysis*; D020543:Proteome / Q000032:analysis; D013019:South Africa; D014862:Wasp Venoms / Q000737:chemistry* / Q000201:enzymology*; D014863:Wasps; D001617:beta-Glucosidase / Q000032:analysis*
chemical_list: D019476:Insect Proteins; D000090263:Leucine-Rich Repeat Proteins; D011506:Proteins; D020543:Proteome; D014862:Wasp Venoms; D001617:beta-Glucosidase