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Bruce A. Webb – 1st expert on this subject based on the ideXlab platform
analysis of gene transcription and relative abundance of the cys motif gene family from Campoletis sonorensis ichnovirus csiv and further characterization of the most abundant cys motif protein whv1 6Insect Molecular Biology, 2013Co-Authors: Torrence A Gill, Bruce A. WebbAbstract:
The cys-motif gene family associated with Campoletis sonorensis ichnovirus contains 10 members, WHv1.6, WHv1.0, VHv1.1, VHv1.4, AHv1.0, A’Hv0.8, FHv1.4, LHv2.8, UHv0.8, and UHv0.8a. The results of this study indicated that, within the encapsidated virion, WHv1.6 is the most abundant cys-motif gene, while the combined AHv genes are the least abundant. During parasitization of Heliothis virescens by Campoletis sonorenis, WHv1.6 transcripts were the mostly highly expressed, while the combined UHv genes had the lowest expression. Further proteomic analysis of WHv1.6 showed that it accumulates at high levels in parasitized plasma by 6 h, and is detectable in the haemocytes, fat body, malpighian tubules, nerve cord and epidermis by 2 days after parasitization. Localization experiments led us to conclude that WHv1.6 interacts with the cell membrane along with other organelles within a virus-infected cell and prevents immunocytes from spreading or adhering to a foreign surface. Similarly to VHv1.4 and VHv1.1, WHv1.6 is able to inhibit the translation of haemocyte and Malpighian tubule RNAs. Our results showed that the expression of cys-motif genes during parasitization is related to the gene copy number of each gene within the encapsidated virion and may also be dependent upon cis-regulatory element activity in different target tissues. In addition, WHv1.6 plays a major role in inhibiting the cellular encapsulation response by H. virescens.
the Campoletis sonorensis ichnovirus vankyrin protein p vank 1 inhibits apoptosis in insect sf9 cellsInsect Molecular Biology, 2009Co-Authors: Angelika Fathgoodin, Jeremy A Kroemer, Bruce A. WebbAbstract:
: The Campoletis sonorensis ichnovirus (CsIV) vankyrin genes encode proteins containing truncated ankyrin repeat domains with sequence homology to the inhibitory domains of NF-kappaB transcription factor inhibitors, IkappaBs. The CsIV vankyrin proteins are thought to be involved in the suppression of NF-kappaB activity during immune response and/or developmental events in the parasitized host. Here we report that when P-vank-1 was expressed stably from Sf9 cells, prolonged survival of these cells was observed after baculovirus infection, UV irradiation, and treatment with the apoptosis-inducing chemical camptothecin compared to untransformed Sf9 cells. Furthermore, P-vank-1 inhibited nuclear and internucleosomal degradation and caspase activity after induction of apoptosis in Sf9 cells stably expressing P-vank-1. This is the first report of a polydnavirus protein with anti-apoptotic function.
quantitative analysis of hemocyte morphological abnormalities associated with Campoletis sonorensis parasitizationJournal of Insect Science, 2004Co-Authors: Matthew W Turnbull, Stacy B Martin, Bruce A. WebbAbstract:
Abstract Endoparasitoids of arthropods evoke host cellular immune responses that result in hemocytic encapsulation of the endoparasitoid, unless these responses are disrupted by the parasite. Our interest has focused on mutualistic viruses found in some hymenopteran endoparasitoids that disrupt hemocyte function and prevent encapsulation. Specifically, the Campoletis sonorensis polydnavirus interacts with wasp factors to suppress immunity via expression of intracellular and secreted viral proteins. To study the roles of specific parasitization-associated factors on immunocyte morphology, fluorescence microscopy was used to visualize the actin cytoskeleton in infected and uninfected cells, or after treatment with C. sonorensis ovarian proteins or plasma from infected larvae. The titer and distribution of F- and G-actin were altered in hemocytes from parasitized insects relative to control cells, with plasma from parasitized larvae having an intermediate effect. This suggests that intracellular and secreted…
Ted C J Turlings – 2nd expert on this subject based on the ideXlab platform
isolation and characterization of polymorphic microsatellite loci in two primary parasitoids of the noctuid spodoptera frugiperda chelonus insularis and Campoletis sonorensis hymenopteraMolecular Ecology Resources, 2009Co-Authors: Violaine Jourdie, Nadir Alvarez, Ted C J Turlings, Pierre FranckAbstract:
Fifteen and 13 microsatellite loci were isolated, respectively, from Campoletis sonorensis Cameron and from Chelonus insularis Cresson. These two parasitic Hymenoptera are primary parasitoids of Lepidoptera in North, Central and South America, including the important agricultural pest Spodoptera frugiperda. Allelic diversity and heterozygosity were quantified in samples from Mexico. Each locus was polymorphic, with the number of alleles ranging from two to 16 in C. sonorensis and from four to 18 in C. insularis. Heterozygosity ranged from 0.088 to 0.403 in C. sonorensis and from 0.106 to 0.458 in C. insularis.
antennal electrophysiological responses of three parasitic wasps to caterpillar induced volatiles from maize zea mays mays cotton gossypium herbaceum and cowpea vigna unguiculataJournal of Chemical Ecology, 2005Co-Authors: Sandrine Gouinguene, J A Pickett, L J Wadhams, Michael A Birkett, Ted C J TurlingsAbstract:
Many parasitic wasps are attracted to volatiles that are released by plants when attacked by potential hosts. The attractiveness of these semiochemicals from damaged plants has been demonstrated in many tritrophic systems, but the physiological mechanisms underlying the insect responses are poorly understood. We recorded the antennal perception by three parasitoids (Cotesia marginiventris, Microplitis rufiventris, and Campoletis sonorensis) to volatiles emitted by maize, cowpea, and cotton plants after attack by the common caterpillar pest Spodoptera littoralis. Gas chromatography-electroantennography (GC-EAG) recordings showed that wasps responded to many, but not all, of the compounds present at the physiologically relevant levels tested. Interestingly, some minor compounds, still unidentified, elicited strong responses from the wasps. These results indicate that wasps are able to detect many odorant compounds released by the plants. It remains to be determined how this information is processed and leads to the specific behavior of the parasitoids.
Howard J. Williams – 3rd expert on this subject based on the ideXlab platform
host selection behavior of Campoletis sonorensis a model systemBiological Control, 1991Co-Authors: Bradleigh S Vinson, Howard J. WilliamsAbstract:
Abstract Plants play a role in the host selection strategy of Campoletis sonorensis , an ichneumonid parasitoid that attacks the larval stages of a number of plant-feeding lepidoptera. We examine the early host selection behavior of C. sonorensis in response to plants and the herbivores that serve as hosts. We bring together some new data and organize the published information to provide an overview of the host selection behavior of Campoletis . We also compare the results of our studies utilizing C. sonorensis , a generalist, to published data concerning two specialists, Microplitis croceipes , a braconid with the same host system, and Diadromus pulchellus , an ichneumonid specializing in both the plant and the hosts it attacks.
stimuli influencing host microhabitat location in the parasitoid Campoletis sonorensisEntomologia Experimentalis Et Applicata, 1991Co-Authors: Heather J. Mcauslane, S B Vinson, Howard J. WilliamsAbstract:
The host microhabitat location behavior of females of the generalist parasitoid Campoletis sonorensis (Cameron) (Hymenoptera: Ichneumonidae) was studied in a wind tunnel. Visual cues associated with the host plant cotton, Gossypium hirsutum L., were important and significantly more parasitoids completed flights to a damaged 4-leaf cotton plant bearing a Heliothis virescens (F.) (Lepidoptera: Noctuidae) larva and frass than to a similarly damaged single leaf with frass and a larva. This difference in completed flights was not due to differences in amounts of volatiles released by the two stimuli, Both naive and experienced parasitoids responded differently to an undamaged cotton leaf, a mechanically damaged leaf, a naturally damaged leaf with the host removed and a naturally damaged leaf with a host larva. Parasitoids completed significantly fewer flights to the undamaged sources of volatiles than to damaged sources of volatiles. Experienced females responded strongly to all types of damage. The number of flights completed by naive females to the three types of damage differed but not significantly and was less than the number completed by experienced females. Components of the preflight experience were varied to determine which factors were responsible for the higher response of experienced females to the host/plant complex. Oviposition was the most important component of this experience. Contact with host frass or plant damage followed by oviposition did not increase the response over that exhibited by females allowed oviposition only. When frass or damaged plant material were contacted without subsequent oviposition, females completed fewer flights than naive females.
Effect of host diet on flight behavior of the parasitoid Campoletis sonorensis (Hymenoptera: Ichneumonidae).Journal of Entomological Science, 1990Co-Authors: Heather J. Mcauslane, S. Bradleigh Vinson, Howard J. WilliamsAbstract:
The effect of larval host diet on the flight behavior and microhabitat preference of the parasitoid, Campoletis sonorensis (Cameron), was studied in a wind tunnel bioassay. Campoletis sonorensis wa…