Campoletis sonorensis is a hymenopteran endoparasitoid that has an obligate mutualism with a ichnovirus (CsIV). During parasitization, C.sonorensis injects CsIV virions, ovarian proteins, and venoms into Lepidopteran hosts to ensure survival of the developing hymenopteran larvae. After infection, CsIV synthesizes proteins in infected hemocytes and other tissues that suppress cellular immune responses, and inhibit humoral immune responses of the Lepidopteran host. The CsIV genome possesses a cysteine-rich motif gene family, designated by ten genes located on 7 proviral segments. Cys-motif genes Vhv1.1 and Vhv1.4 have been implicated in altering cytoskeletal shape of immunocytes (granulocytes & plasmocytes), post-translational inhibition of specific proteins, and delayed development of Lepidopteran host. All the cys-motif genes have structural similarities to another antimicrobial peptide, teratocyte secretory protein (TSP14), secreted by teratocytes associated with an endoparasitoid hymenopteran Microplitis croceipes larvae, which also harbors a bracovirus in its genome. During parasitization cys-motif genes, Vhv1.1, Vhv1.4, Whv1.0, Whv1.6 are expressed at high levels in parasitized Lepidopteran tissues and hemolymph. These genes were cloned into PKM24 vector that contains mirabias mosiac full-length transcript promoter (MMVflt), signal peptide, and kanamycin resistance gene for selection purposes. The genes were transformed through agromediated transformation into nicotiana tabacum tobacco species. Western blots were performed to confirm the presence of these proteins in tobacco and feeding bioassays using Heliothis virescens were performed to assess the antimicrobial affect of each gene.
Species 1: Hymenoptera Ichneumonidae Campoletis sonorensis
Species 2: Lepidoptera Noctuidae Heliothis virescens (Tobacco Budworm)
Species 3: Hymenoptera Braconidae Microplitis croceipes
Keywords: transgenic tobacco, teratocytes
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