Genome-wide patterns of bracovirus chromosomal integration into multiple host tissues during parasitism

Bracoviruses are domesticated viruses found in parasitic wasp genomes. They are composed of genes of nudiviral origin involved in particle production and proviral segments encoding virulence genes necessary for parasitism success. During particle production, proviral segments are amplified and individually packaged as DNA circles in nucleocapsids. These particles are injected by parasitic waspstogether with their eggs into host larvae. Bracovirus circles of two wasp species were reported toundergo chromosomal integration in parasitized host hemocytes, through a conserved sequence named Host Integration Motif (HIM). Here, we used bulk Illumina sequencing to survey integrations of Cotesia typhae bracovirus circles in the DNA of its host, the maize corn borer ( Sesamia nonagrioides ) seven days after parasitism. First, assembly and annotation of a high-quality genome for C. typhae enabled us to characterize 27 proviral segments clustered in proviral loci. Using these data, we characterized large numbers of chromosomal integrations (from 12 to 85 events per host haploid genome) for all 16 bracovirus circles containing a HIM. Integrations were found in four S. nonagrioides tissues and in the body of a caterpillar in which parasitism had failed. The 12 remaining circles do not integrate but are maintained at high levels in host tissues. Surprisingly, we found that HIM-mediated chromosomal integration has occurred at least six times accidentally in thewasp germline during evolution. Overall, our study furthers our understanding of wasp-host genome interactions and supports HIM-mediated chromosomal integration as a possible mechanism ofhorizontal transfer from wasps to their hosts. Importance Bracoviruses are endogenous domesticated viruses of parasitoid wasps that are injected together with wasp eggs into wasp host larvae during parasitism. Several studies have shown that some DNA circles packaged into bracovirus particles become integrated into host somatic genomes during parasitism, but the phenomenon has never been studied using non-targeted approaches. Here we use bulk Illumina sequencing to systematically characterize and quantify bracovirus circle integrations that occur in four tissues of the Mediterranean corn borer ( Sesamia nonagrioides ) during parasitism by the Cotesia typhae wasp. Our analysis reveals that all circles containing a host integration motif (HIM) integrate at substantial levels (from 12 to 85 integrations per host cell in total) in all tissues while other circles do not integrate. In addition to shedding new light on wasp-bracovirus-host interaction, our study supports HIM-mediated chromosomal integration of bracovirus as a possible source of wasp-to-host horizontal transfer with long term evolutionary consequences.

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Native parasitoids and their potential to control the invasive leafminer,Cameraria ohridellaDESCH. & DIM. (Lep.: Gracillariidae)

Bulletin of Entomological Research ◽

10.1017/s0007485308005695 ◽

2008 ◽

Vol 98 (4) ◽

pp. 379-387 ◽

Cited By ~ 14

Author(s):

T. Klug ◽

R. Meyhöfer ◽

M. Kreye ◽

M. Hommes

Keyword(s):

Leaf Litter ◽

Parasitic Wasp ◽

Horse Chestnut ◽

Parasitoid Species ◽

Wasp Species ◽

Native Parasitoids ◽

Long Run ◽

The Moment ◽

Pnigalio Agraules ◽

Potential Efficiency

AbstractIn spite of the fact that since the end of the eighties, the horse chestnut leafminer,Cameraria ohridella, has established itself throughout Europe, native predators such as ants and birds are not attuned to this neozoic species. In contrast, several parasitic wasp species already started to exploit the invasive horse chestnut leafminer, but until now parasitation rates are quite low, mainly because of asynchrony in the lifecycles of parasitoids and host. Only the removal of leaf litter, in which pupae hibernate, is at the moment a strategy to reduce the infestation level in the next year. Unfortunately, not only hibernating horse chestnut leafminers but also parasitoids are removed, and important resources for biocontrol are unused. In the current study, we investigated the potential efficiency of the horse chestnut leafminer parasitoid complex extracted from leaf litter in defined environments. Parasitoids were released at different densities to investigate density dependence in parasitation rates.Although seven different species were released in our experiments, onlyPnigalio agraulesturned out to be responsible for biocontrol ofC. ohridella. We recorded parasitation rates of up to 35%. Overall, parasitation rates were independent of the leafminer density but increased fourfold if ten times more parasitoid individuals were released. Unfortunately, none of the parasitoid species could be established in the experimental units in the long run. Results are compared to other parasitoid-leafminer systems, and promotion of horse chestnut leafminer parasitoids to support natural selection and biological control of the horse chestnut leafminer is discussed.

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Macrophages as Emerging Key Players in Mitochondrial Transfers

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.747377 ◽

2021 ◽

Vol 9 ◽

Author(s):

Yidan Pang ◽

Changqing Zhang ◽

Junjie Gao

Keyword(s):

Cardiovascular Diseases ◽

Metabolic Regulation ◽

Inflammatory Diseases ◽

Negative Influence ◽

Immune Defense ◽

The Body ◽

Key Players ◽

Current Therapies ◽

Obesity And Cancer ◽

Host Tissues

Macrophages are a group of heterogeneous cells widely present throughout the body. Under the influence of their specific environments, via both contact and noncontact signals, macrophages integrate into host tissues and contribute to their development and the functions of their constituent cells. Mitochondria are essential organelles that perform intercellular transfers to regulate cell homeostasis. Our review focuses on newly discovered roles of mitochondrial transfers between macrophages and surrounding cells and summarizes emerging functions of macrophages in transmitophagy, metabolic regulation, and immune defense. We also discuss the negative influence of mitochondrial transfers on macrophages, as well as current therapies targeting mitochondria in macrophages. Regulation of macrophages through mitochondrial transfers between macrophages and their surrounding cells is a promising therapy for various diseases, including cardiovascular diseases, inflammatory diseases, obesity, and cancer.

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Response to conspecific and heterospecific semiochemicals by Sesamia nonagrioides (L.) (Lepidoptera: Noctuidae) gravid females

Bulletin of Entomological Research ◽

10.1017/s0007485315000206 ◽

2015 ◽

Vol 105 (3) ◽

pp. 347-354 ◽

Cited By ~ 4

Author(s):

D. Cruz ◽

M. Eizaguirre

Keyword(s):

Minor Component ◽

Pheromone Component ◽

Sesamia Nonagrioides ◽

Sexual Pheromone ◽

Electrophysiological Response ◽

Corn Borer ◽

Pheromone Components ◽

Gravid Females ◽

Electroantennogram Recordings ◽

Pheromone Blend

AbstractThe Mediterranean corn borer, Sesamia nonagrioides, occurs sympatrically in the northeast of Spain with other lepidopteran pests such as Ostrinia nubilalis and Mythimna unipuncta. In this study, we evaluated the electrophysiological and behavioural response of mated and unmated females and males of S. nonagrioides to their own complete pheromone blend, to its own four components separately, and to the pheromone components of the sympatric species O. nubilalis and M. unipuncta. Results of the electroantennogram recordings revealed that females of S. nonagrioides can detect their own pheromone blend and its individual components. Moreover, our results show that unmated females and males of S. nonagrioides are more sensitive to the female pheromone, showing higher electrophysiological response than the mated females and males. Electroantennogram recordings showed that males and females can detect the major sexual pheromone component of O. nubilalis (Z)-11-tetradecenyl acetate and the minor component of the pheromone of M. unipuncta (Z)-9-hexadecenyl acetate. When the sex pheromone stimulus was presented in the dual-choice assays, gravid females of S. nonagrioides were attracted to both their own complete pheromone blend and one of their own minor pheromone components, (Z)-11-hexadecenal, but the major sexual pheromone component of O. nubilalis acts as a behavioural antagonist to the females.

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Genetic Manipulation of Arterivirus Alternative mRNA Leader-Body Junction Sites Reveals Tight Regulation of Structural Protein Expression

Journal of Virology ◽

10.1128/jvi.74.24.11642-11653.2000 ◽

2000 ◽

Vol 74 (24) ◽

pp. 11642-11653 ◽

Cited By ~ 37

Author(s):

Alexander O. Pasternak ◽

Alexander P. Gultyaev ◽

Willy J. M. Spaan ◽

Eric J. Snijder

Keyword(s):

Rna Structure ◽

The Body ◽

Equine Arteritis Virus ◽

Site Directed Mutagenesis ◽

Structural Proteins ◽

Limiting Factors ◽

Progeny Virus ◽

Structural Protein ◽

Sequence Element ◽

Conserved Sequence

ABSTRACT To express its structural proteins, the arterivirus Equine arteritis virus (EAV) produces a nested set of six subgenomic (sg) RNA species. These RNA molecules are generated by a mechanism of discontinuous transcription, during which a common leader sequence, representing the 5′ end of the genomic RNA, is attached to the bodies of the sg RNAs. The connection between the leader and body parts of an mRNA is formed by a short, conserved sequence element termed the transcription-regulating sequence (TRS), which is present at the 3′ end of the leader as well as upstream of each of the structural protein genes. With the exception of RNA3, only one body TRS was previously assumed to be used to join the leader and body of each EAV sg RNA. Here we show that for the synthesis of two other sg RNAs, RNA4 and RNA5, alternative leader-body junction sites that differ substantially in transcriptional activity are used. By site-directed mutagenesis of an EAV infectious cDNA clone, the alternative TRSs used to generate RNA3, -4, and -5 were inactivated, which strongly influenced the corresponding RNA levels and the production of infectious progeny virus. The relative amounts of RNA produced from alternative TRSs differed significantly and corresponded to the relative infectivities of the virus mutants. This strongly suggested that the structural proteins that are expressed from these RNAs are limiting factors during the viral life cycle and that the discontinuous step in sg RNA synthesis is crucial for the regulation of their expression. On the basis of a theoretical analysis of the predicted RNA structure of the 3′ end of the EAV genome, we propose that the local secondary RNA structure of the body TRS regions is an important factor in the regulation of the discontinuous step in EAV sg mRNA synthesis.

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CREB expression in the brains of two closely related parasitic wasp species that differ in long-term memory formation

Insect Molecular Biology ◽

10.1111/j.1365-2583.2010.00997.x ◽

2010 ◽

Vol 19 (3) ◽

pp. 367-379 ◽

Cited By ~ 5

Author(s):

M. Van Den Berg ◽

P. Verbaarschot ◽

S. Hontelez ◽

L. E. M. Vet ◽

M. Dicke ◽

...

Keyword(s):

Parasitic Wasp ◽

Memory Formation ◽

Long Term Memory ◽

Wasp Species ◽

Term Memory

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UHPLC–MS Analysis of Juvenile Hormone II in Mediterranean Corn Borer (Sesamia nonagrioides) Hemolymph Using Various Ionization Techniques

Journal of Agricultural and Food Chemistry ◽

10.1021/jf204621h ◽

2012 ◽

Vol 60 (12) ◽

pp. 3020-3025 ◽

Cited By ~ 6

Author(s):

Francisca Vilaró ◽

Meritxell Pérez-Hedo ◽

Jordi Eras ◽

Ramon Canela ◽

Matilde Eizaguirre

Keyword(s):

Juvenile Hormone ◽

Sesamia Nonagrioides ◽

Corn Borer ◽

Ms Analysis

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Cadherin Characterization and Cytochrome Oxidase (COI) HRM Analysis in Different Geographical Populations of the Mediterranean Corn Borer, Sesamia nonagrioides

Journal of Agricultural Science ◽

10.5539/jas.v6n1p173 ◽

2013 ◽

Vol 6 (1) ◽

Author(s):

Aliki Kapazoglou ◽

Stefanos S. Andreadis ◽

Vicky Drossou ◽

Panagiotis Madesis ◽

Matilda Savopoulou-Soultani ◽

...

Keyword(s):

Cytochrome Oxidase ◽

Sesamia Nonagrioides ◽

Corn Borer ◽

Hrm Analysis ◽

Geographical Populations ◽

The Mediterranean

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Chromosomal resolution reveals symbiotic virus colonization of parasitic wasp genomes

10.1101/2020.03.19.994459 ◽

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.

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Effects of antioxidant activity of black maize in corn borer larval survival and growth

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2018161-11939 ◽

2018 ◽

Vol 16 (1) ◽

pp. e1004 ◽

Cited By ~ 1

Author(s):

Pedro Revilla ◽

Pilar Soengas ◽

Rosa A. Malvar

Keyword(s):

Antioxidant Activity ◽

Vitamin C ◽

Control Diet ◽

Control Treatment ◽

Sesamia Nonagrioides ◽

Maize Flour ◽

Corn Borer ◽

Positive Effects ◽

Other Substances ◽

Survival And Growth

Antioxidant activity (AA) of black maize kernels attributed mainly to polyphenols has potential effects on health and possible defense functions against pests. Our objective was to evaluate the effects of maize polyphenols and AA in survival and growth of larvae of the corn borer Sesamia nonagrioides. We carried out two bioassays with S. nonagrioides larvae grown in artificial diet with white and black maize flour and control. AA was tested spectrophotometrically on each of the diets using four methods. The different measurements of AA were strongly correlated, indicating that these measurements were highly reliable. The control diet, the white-maize-diet and black-maize-diet with vitamin C and without H2O2 had the highest antioxidant activity. The processing of the maize flour altered the AA of the polyphenols. The control treatment had the highest AA, and vitamin C had stronger AA than polyphenols. AA of vitamin C hides that of polyphenols probably due to environmental effects, dilution of polyphenols, or interactions with other substances. Larvae grew more in the control diet and the addition of H2O2 had not significant effects on weight. There was a weak rank correlation between AA and larval weight. Mortality was lowest for the control diet with or without H2O2 followed by white maize with or without H2O2 and black maize without H2O2. Effects of polyphenols depend on other substances that might interact with them. The results indicate that antioxidant activity has insecticide effects on young larvae and, as the larvae grow, antioxidants have positive effects on larvae.

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