scholarly journals Polydnavirus replication: the EP1 segment of the parasitoid wasp Cotesia congregata is amplified within a larger precursor molecule

2002 ◽  
Vol 83 (8) ◽  
pp. 2035-2045 ◽  
Author(s):  
F. Pasquier-Barre ◽  
C. Dupuy ◽  
E. Huguet ◽  
F. Monteiro ◽  
A. Moreau ◽  
...  
Keyword(s):  
Adult Development ◽  
Genomic Dna ◽  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Precursor Molecule ◽  
Molecular Analyses ◽  
Virus Particles ◽  
Cotesia Congregata ◽  
Virus Sequence ◽  
Shed Light

Polydnaviruses are unique viruses: they are essential for successful parasitism by tens of thousands of species of parasitoid wasps. These viruses are obligatorily associated with the wasps and are injected into the host during oviposition. Molecular analyses have shown that each virus sequence in the segmented polydnavirus genome is present in the wasp DNA in two forms: a circular form found in the virus particles and an integrated form found in the wasp chromosomes. Recent studies performed on polydnaviruses from braconid wasps suggested that the circular forms were excised from the chromosome. The different forms of the EP1 circle of Cotesia congregata polydnavirus during the pupal–adult development of the parasitoid wasp were analysed. Unexpectedly, an off-size fragment formerly used to diagnose the integration of the EP1 sequence into wasp genomic DNA was found to be amplified in female wasps undergoing virus replication. The EP1 sequence is amplified within a larger molecule comprising at least two virus segments. The amplified molecule is different from the EP1 chromosomally integrated form and is not encapsidated into virus particles. These findings shed light on a new step towards EP1 circle production: the amplification of virus sequences preceding individual circle excision.

scholarly journals Cotesia congregata Bracovirus Circles Encoding PTP and Ankyrin Genes Integrate into the DNA of Parasitized Manduca sexta Hemocytes

2018 ◽  
Vol 92 (15) ◽  
Author(s):  
Germain Chevignon ◽  
Georges Periquet ◽  
Gabor Gyapay ◽  
Nathalie Vega-Czarny ◽  
Karine Musset ◽  
...  
Keyword(s):  
Manduca Sexta ◽  
High Throughput Sequencing ◽  
Particle Production ◽  
Parasitoid Wasp ◽  
Gene Families ◽  
Parasitoid Wasps ◽  
Content Type ◽  
Virulence Proteins ◽  
Cotesia Congregata ◽  
Dividing Cells

ABSTRACT Polydnaviruses (PDVs) are essential for the parasitism success of tens of thousands of species of parasitoid wasps. PDVs are present in wasp genomes as proviruses, which serve as the template for the production of double-stranded circular viral DNA carrying virulence genes that are injected into lepidopteran hosts. PDV circles do not contain genes coding for particle production, thereby impeding viral replication in caterpillar hosts during parasitism. Here, we investigated the fate of PDV circles of Cotesia congregata bracovirus during parasitism of the tobacco hornworm, Manduca sexta, by the wasp Cotesia congregata. Sequences sharing similarities with host integration motifs (HIMs) of Microplitis demolitor bracovirus (MdBV) circles involved in integration into DNA could be identified in 12 CcBV circles, which encode PTP and VANK gene families involved in host immune disruption. A PCR approach performed on a subset of these circles indicated that they persisted in parasitized M. sexta hemocytes as linear forms, possibly integrated in host DNA. Furthermore, by using a primer extension capture method based on these HIMs and high-throughput sequencing, we could show that 8 out of 9 circles tested were integrated in M. sexta hemocyte genomic DNA and that integration had occurred specifically using the HIM, indicating that an HIM-mediated specific mechanism was involved in their integration. Investigation of BV circle insertion sites at the genome scale revealed that certain genomic regions appeared to be enriched in BV insertions, but no specific M. sexta target site could be identified. IMPORTANCE The identification of a specific and efficient integration mechanism shared by several bracovirus species opens the question of its role in braconid parasitoid wasp parasitism success. Indeed, results obtained here show massive integration of bracovirus DNA in somatic immune cells at each parasitism event of a caterpillar host. Given that bracoviruses do not replicate in infected cells, integration of viral sequences in host DNA might allow the production of PTP and VANK virulence proteins within newly dividing cells of caterpillar hosts that continue to develop during parasitism. Furthermore, this integration process could serve as a basis to understand how PDVs mediate the recently identified gene flux between parasitoid wasps and Lepidoptera and the frequency of these horizontal transfer events in nature.

scholarly journals Sight of parasitoid wasps accelerates sexual behavior and upregulates a micropeptide gene in Drosophila

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shimaa A. M. Ebrahim ◽  
Gaëlle J. S. Talross ◽  
John R. Carlson
Keyword(s):  
Gene Expression ◽  
Nervous System ◽  
Sexual Behavior ◽  
Behavioral Response ◽  
Mutational Analysis ◽  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Wasp Species ◽  
Defensive Responses ◽  
Vast Range

AbstractParasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression.

scholarly journals Apomictic parthenogenesis in a parasitoid waspMeteorus pulchricornis, uncommon in the haplodiploid order Hymenoptera

2014 ◽  
Vol 104 (3) ◽  
pp. 307-313 ◽  
Author(s):  
Y. Tsutsui ◽  
K. Maeto ◽  
K. Hamaguchi ◽  
Y. Isaki ◽  
Y. Takami ◽  
...  
Keyword(s):  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Genetic Studies ◽  
Insect Order ◽  
Egg Maturation ◽  
Polar Bodies ◽  
Lepidopteran Larvae ◽  
Apomictic Parthenogenesis ◽  
Meteorus Pulchricornis ◽  
New Type

AbstractAlthough apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid waspMeteorus pulchricornis(Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvaeSpodoptera litura(Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.

scholarly journals Functional endogenous viral elements in the genome of the parasitoid wasp Cotesia congregata : insights into the evolutionary dynamics of bracoviruses

2013 ◽  
Vol 368 (1626) ◽  
pp. 20130047 ◽  
Author(s):  
Annie Bézier ◽  
Faustine Louis ◽  
Séverine Jancek ◽  
Georges Periquet ◽  
Julien Thézé ◽  
...  
Keyword(s):  
Virulence Genes ◽  
Evolutionary Dynamics ◽  
Genomic Organization ◽  
Parasitoid Wasp ◽  
Comparative Genomic ◽  
Conserved Synteny ◽  
Closely Related Species ◽  
Cotesia Congregata ◽  
Genomic Analyses ◽  
Endogenous Viral Elements

Bracoviruses represent the most complex endogenous viral elements (EVEs) described to date. Nudiviral genes have been hosted within parasitoid wasp genomes since approximately 100 Ma. They play a crucial role in the wasp life cycle as they produce bracovirus particles, which are injected into parasitized lepidopteran hosts during wasp oviposition. Bracovirus particles encapsidate multiple dsDNA circles encoding virulence genes. Their expression in parasitized caterpillars is essential for wasp parasitism success. Here, we report on the genomic organization of the proviral segments (i.e. master sequences used to produce the encapsidated dsDNA circles) present in the Cotesia congregata parasitoid wasp genome. The provirus is composed of a macrolocus, comprising two-thirds of the proviral segments and of seven dispersed loci, each containing one to three segments. Comparative genomic analyses with closely related species gave insights into the evolutionary dynamics of bracovirus genomes. Conserved synteny in the different wasp genomes showed the orthology of the proviral macrolocus across different species. The nudiviral gene odv-e66-like1 is conserved within the macrolocus, suggesting an ancient co-localization of the nudiviral genome and bracovirus proviral segments. By contrast, the evolution of proviral segments within the macrolocus has involved a series of lineage-specific duplications.

Parasitization of Manduca sexta larvae by the parasitoid wasp Cotesia congregata induces an impaired host immune response

2005 ◽  
Vol 51 (5) ◽  
pp. 505-512 ◽  
Author(s):  
Kevin E. Amaya ◽  
Sassan Asgari ◽  
Richard Jung ◽  
Melissa Hongskula ◽  
Nancy E. Beckage
Keyword(s):  
Immune Response ◽  
Manduca Sexta ◽  
Parasitoid Wasp ◽  
Host Immune Response ◽  
Cotesia Congregata ◽  
Manduca Sexta Larvae

scholarly journals Comprehensive Transcriptome of the Maize Stalk Borer, Busseola fusca, from Multiple Tissue Types, Developmental Stages, and Parasitoid Wasp Exposures

2020 ◽  
Vol 12 (12) ◽  
pp. 2554-2560
Author(s):  
Keyword(s):  
Target Genes ◽  
Developmental Stages ◽  
Management Strategies ◽  
Busseola Fusca ◽  
Parasitoid Wasp ◽  
Sub Saharan Africa ◽  
Biological Research ◽  
Parasitoid Wasps ◽  
Pest Species ◽  
Stalk Borer

Abstract Busseola fusca (Fuller) (Lepidoptera: Noctuidae), the maize stalk borer, is a widespread crop pest in sub-Saharan Africa that has been the focus of biological research and intensive management strategies. Here, we present a comprehensive annotated transcriptome of B. fusca (originally collected in the Western Province of Kenya) based on ten pooled libraries including a wide array of developmental stages, tissue types, and exposures to parasitoid wasps. Parasitoid wasps have been used as a form of biocontrol to try and reduce crop losses with variable success, in part due to differential infectivities and immune responses among wasps and hosts. We identified a number of loci of interest for pest management, including genes potentially involved in chemoreception, immunity, and response to insecticides. The comprehensive sampling design used expands our current understanding of the transcriptome of this species and deepens the list of potential target genes for future crop loss mitigation, in addition to highlighting candidate loci for differential expression and functional genetic analyses in this important pest species.

scholarly journals Chromosomal resolution reveals symbiotic virus colonization of parasitic wasp genomes

2020 ◽  
Author(s):  
Jérémy Gauthier ◽  
Hélène Boulain ◽  
Joke J.F.A. van Vugt ◽  
Lyam Baudry ◽  
Emma Persyn ◽  
...  
Keyword(s):  
Particle Production ◽  
Parasitic Wasp ◽  
Viral Gene Expression ◽  
Parasitoid Wasp ◽  
Viral Gene ◽  
Parasitoid Wasps ◽  
Genomic Comparison ◽  
Immune Genes ◽  
Endogenous Viruses ◽  
First Time

AbstractMost endogenous viruses, an important proportion of eukaryote genomes, are doomed to slowly decay. Little is known, however, on how they evolve when they confer a benefit to their host. Bracoviruses are essential for the parasitism success of parasitoid wasps, whose genomes they integrated ~103 million years ago. Here we show, from the assembly of a parasitoid wasp genome, for the first time at a chromosomal scale, that symbiotic bracovirus genes spread to and colonized all the chromosomes. Moreover, large viral clusters are stably maintained suggesting strong evolutionary constraints. Genomic comparison with another wasps revealed that this organization was already established ~53 mya. Transcriptomic analyses highlight temporal synchronization of viral gene expression, leading to particle production. Immune genes are not induced, however, indicating the virus is not perceived as foreign by the wasp. This recognition suggests that no conflicts remain between symbiotic partners when benefits to them converge.

scholarly journals Variation in the diversity and richness of parasitoid wasps based on sampling effort

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4642 ◽  
Author(s):  
Thomas E. Saunders ◽  
Darren F. Ward
Keyword(s):  
Species Richness ◽  
Austral Summer ◽  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Sampling Effort ◽  
Summer Period ◽  
Wasp Species ◽  
The Cost ◽  
Number Of Individuals ◽  
The Relationship

Parasitoid wasps are a mega-diverse, ecologically dominant, but poorly studied component of global biodiversity. In order to maximise the efficiency and reduce the cost of their collection, the application of optimal sampling techniques is necessary. Two sites in Auckland, New Zealand were sampled intensively to determine the relationship between sampling effort and observed species richness of parasitoid wasps from the family Ichneumonidae. Twenty traps were deployed at each site at three different times over the austral summer period, resulting in a total sampling effort of 840 Malaise-trap-days. Rarefaction techniques and non-parametric estimators were used to predict species richness and to evaluate the variation and completeness of sampling. Despite an intensive Malaise-trapping regime over the summer period, no asymptote of species richness was reached. At best, sampling captured two-thirds of parasitoid wasp species present. The estimated total number of species present depended on the month of sampling and the statistical estimator used. Consequently, the use of fewer traps would have caught only a small proportion of all species (one trap 7–21%; two traps 13–32%), and many traps contributed little to the overall number of individuals caught. However, variation in the catch of individual Malaise traps was not explained by seasonal turnover of species, vegetation or environmental conditions surrounding the trap, or distance of traps to one another. Overall the results demonstrate that even with an intense sampling effort the community is incompletely sampled. The use of only a few traps and/or for very short periods severely limits the estimates of richness because (i) fewer individuals are caught leading to a greater number of singletons; and (ii) the considerable variation of individual traps means some traps will contribute few or no individuals. Understanding how sampling effort affects the richness and diversity of parasitoid wasps is a useful foundation for future studies.

scholarly journals Strong selective pressure by parasitoids mitigates the costs of consuming chemically defended plants

2021 ◽  
Author(s):  
Deidra J. Jacobsen
Keyword(s):  
Manduca Sexta ◽  
Natural Enemies ◽  
Developmental Stages ◽  
Parasitoid Wasp ◽  
Field Measurements ◽  
Secondary Compounds ◽  
List Type ◽  
Plant Secondary Compounds ◽  
Defensive Compounds ◽  
Cotesia Congregata

AbstractCo-evolutionary interactions between plants and herbivores have led to a range of plant defenses that minimize insect damage and a suite of counter-adaptations that allow herbivores to feed on defended plants. Consumption of plant secondary compounds results in herbivore growth and developmental costs but can be beneficial if eating these secondary compounds results in deterrence or harm to natural enemies.To test the role of secondary compounds on herbivore fitness in the context of natural enemies, I combined field measurements of the prevalence of a parasitoid wasp (Cotesia congregata) with detailed measurements of the costs of plant secondary compounds on growth, immune, and fitness traits across developmental stages in the herbivore Manduca sexta. When M. sexta larvae consume defended plants, Cotesia congregata are known to have reduced success. However, this anti-enemy benefit to the M. sexta host must be considered in relationship to parasitoid abundance and the type and strength of the fitness costs M. sexta incurs feeding on plant secondary compounds.I found that Cotesia congregata parasitoids exert large negative selective pressures, killing 31-57% of M. sexta larvae in the field. Manduca sexta developed fastest during the instars most at risk for parasitoid oviposition but growth was slowed by consumption of plant secondary compounds (nicotine and rutin). These negative size effects at the larval stage carried over to influence adult traits associated with flight and mating but there were no immune, survival, or fecundity costs of consuming plant defensive compounds as larvae.Synthesis. These results suggest that the developmental costs experienced by M. sexta herbivores consuming defensive compounds may be outweighed by a survival benefit in the face of abundant enemy pressures.

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