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John H. Werren - One of the best experts on this subject based on the ideXlab platform.
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genome report whole genome sequence and annotation of the parasitoid jewel wasp Nasonia giraulti laboratory strain rv2x u
G3: Genes Genomes Genetics, 2020Co-Authors: Xiaozhu Wang, John H. Werren, Jeremy A. Lynch, Ellen O. Martinson, Yogeshwar D Kelkar, Xiao Xiong, Chao Zhang, Xu WangAbstract:Jewel wasps in the genus of Nasonia are parasitoids with haplodiploidy sex determination, rapid development and are easy to culture in the laboratory. They are excellent models for insect genetics, genomics, epigenetics, development, and evolution. Nasonia vitripennis (Nv) and N. giraulti (Ng) are closely-related species that can be intercrossed, particularly after removal of the intracellular bacterium Wolbachia, which serve as a powerful tool to map and positionally clone morphological, behavioral, expression and methylation phenotypes. The Nv reference genome was assembled using Sanger, PacBio and Nanopore approaches and annotated with extensive RNA-seq data. In contrast, Ng genome is only available through low coverage resequencing. Therefore, de novo Ng assembly is in urgent need to advance this system. In this study, we report a high-quality Ng assembly using 10X Genomics linked-reads with 670X sequencing depth. The current assembly has a genome size of 259,040,977 bp in 3,160 scaffolds with 38.05% G-C and a 98.6% BUSCO completeness score. 97% of the RNA reads are perfectly aligned to the genome, indicating high quality in contiguity and completeness. A total of 14,777 genes are annotated in the Ng genome, and 72% of the annotated genes have a one-to-one ortholog in the Nv genome. We reported 5 million Ng-Nv SNPs which will facility mapping and population genomic studies in Nasonia. In addition, 42 Ng-specific genes were identified by comparing with Nv genome and annotation. This is the first de novo assembly for this important species in the Nasonia model system, providing a useful new genomic toolkit.
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Allele-Specific Transcriptome and Methylome Analysis Reveals Stable Inheritance and Cis-Regulation of DNA Methylation in Nasonia.
PLoS biology, 2016Co-Authors: Xu Wang, John H. Werren, Andrew G. ClarkAbstract:Gene expression divergence between closely related species could be attributed to both cis- and trans- DNA sequence changes during evolution, but it is unclear how the evolutionary dynamics of epigenetic marks are regulated. In eutherian mammals, biparental DNA methylation marks are erased and reset during gametogenesis, resulting in paternal or maternal imprints, which lead to genomic imprinting. Whether DNA methylation reprogramming exists in insects is not known. Wasps of the genus Nasonia are non-social parasitoids that are emerging as a model for studies of epigenetic processes in insects. In this study, we quantified allele-specific expression and methylation genome-wide in Nasonia vitripennis and Nasonia giraulti and their reciprocal F1 hybrids. No parent-of-origin effect in allelic expression was found for >8,000 covered genes, suggesting a lack of genomic imprinting in adult Nasonia. As we expected, both significant cis- and trans- effects are responsible for the expression divergence between N. vitripennis and N. giraulti. Surprisingly, all 178 differentially methylated genes are also differentially methylated between the two alleles in F1 hybrid offspring, recapitulating the parental methylation status with nearly 100% fidelity, indicating the presence of strong cis-elements driving the target of gene body methylation. In addition, we discovered that total and allele-specific expression are positively correlated with allele-specific methylation in a subset of the differentially methylated genes. The 100% cis-regulation in F1 hybrids suggests the methylation machinery is conserved and DNA methylation is targeted by cis features in Nasonia. The lack of genomic imprinting and parent-of-origin differentially methylated regions in Nasonia, together with the stable inheritance of methylation status between generations, suggests either a cis-regulatory motif for methylation at the DNA level or highly stable inheritance of an epigenetic signal in Nasonia.
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Nasonia vitripennis venom causes targeted gene expression changes in its fly host.
Molecular ecology, 2014Co-Authors: Ellen O. Martinson, David A. Wheeler, Jeremy Wright, Mrinalini, Aisha Siebert, John H. WerrenAbstract:Parasitoid wasps are diverse and ecologically important insects that use venom to modify their host’s metabolism for the benefit of the parasitoid’s offspring. Thus, the effects of venom can be considered an ‘extended phenotype’ of the wasp. The model parasitoid wasp Nasonia vitripennis has approximately 100 venom proteins, 23 of which do not have sequence similarity to known proteins. Envenomation by N. vitripennis has previously been shown to induce developmental arrest, selective apoptosis and alterations in lipid metabolism in flesh fly hosts. However, the full effects of Nasonia venom are still largely unknown. In this study, we used high throughput RNA sequencing (RNA-Seq) to characterize global changes in Sarcophaga bullata (Diptera) gene expression in response to envenomation by N. vitripennis. Surprisingly, we show that Nasonia venom targets a small subset of S. bullata loci, with ~2% genes being differentially expressed in response to envenomation. Strong upregulation of enhancer of split complex genes provides a potential molecular mechanism that could explain the observed neural cell death and developmental arrest in envenomated hosts. Significant increases in antimicrobial peptides and their corresponding regulatory genes provide evidence that venom could be selectively activating certain immune responses of the hosts. Further, we found differential expression of genes in several metabolic pathways, including glycolysis and gluconeogenesis that may be responsible for the decrease in pyruvate levels found in envenomated hosts. The targeting of Nasonia venom effects to a specific and limited set of genes provides insight into the interaction between the ectoparasitoid wasp and its host.
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cuticular hydrocarbon divergence in the jewel wasp Nasonia evolutionary shifts in chemical communication channels
Journal of Evolutionary Biology, 2013Co-Authors: Jan Buellesbach, John H. Werren, Rhitoban Raychoudhury, Leo W Beukeboom, Jürgen Gadau, Thomas Schmitt, Felix EchingerAbstract:The evolution and maintenance of intraspecific communication channels constitute a key feature of chemical signalling and sexual communication. However, how divergent chemical communication channels evolve while maintaining their integrity for both sender and receiver is poorly understood. In this study, we compare male and female cuticular hydrocarbon (CHC) profiles in the jewel wasp genus Nasonia, analyse their chemical divergence and investigate their role as species-specific sexual signalling cues. Males and females of all four Nasonia species showed unique, nonoverlapping CHC profiles unambiguously separating them. Surprisingly, male and female phylogenies based on the chemical distances between their CHC profiles differed dramatically, where only male CHC divergence parallels the molecular phylogeny of Nasonia. In particular, N. giraulti female CHC profiles were the most divergent from all other species and very different from its most closely related sibling species N. oneida. Furthermore, although our behavioural assays indicate that female CHC profiles can generally be perceived as sexual cues attracting males in Nasonia, this function has apparently been lost in the highly divergent female N. giraulti CHC profiles. Curiously, N. giraulti males are still attracted to heterospecific, but not to conspecific female CHC profiles. We suggest that this striking discrepancy has been caused by an extensive evolutionary shift in female N. giraulti CHC profiles, which are no longer used as conspecific recognition cues. Our study constitutes the first report of an apparent abandonment of a sexual recognition cue that the receiver did not adapt to.
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Function and Evolution of DNA Methylation in Nasonia vitripennis
PLoS genetics, 2013Co-Authors: Xu Wang, Jeonghyeon Choi, John K Colbourne, Amanda Avery, Andrew G. Clark, David A. Wheeler, Alfredo Rago, John H. WerrenAbstract:The parasitoid wasp Nasonia vitripennis is an emerging genetic model for functional analysis of DNA methylation. Here, we characterize genome-wide methylation at a base-pair resolution, and compare these results to gene expression across five developmental stages and to methylation patterns reported in other insects. An accurate assessment of DNA methylation across the genome is accomplished using bisulfite sequencing of adult females from a highly inbred line. One-third of genes show extensive methylation over the gene body, yet methylated DNA is not found in non-coding regions and rarely in transposons. Methylated genes occur in small clusters across the genome. Methylation demarcates exon-intron boundaries, with elevated levels over exons, primarily in the 5' regions of genes. It is also elevated near the sites of translational initiation and termination, with reduced levels in 5' and 3' UTRs. Methylated genes have higher median expression levels and lower expression variation across development stages than non-methylated genes. There is no difference in frequency of differential splicing between methylated and non-methylated genes, and as yet no established role for methylation in regulating alternative splicing in Nasonia. Phylogenetic comparisons indicate that many genes maintain methylation status across long evolutionary time scales. Nasonia methylated genes are more likely to be conserved in insects, but even those that are not conserved show broader expression across development than comparable non-methylated genes. Finally, examination of duplicated genes shows that those paralogs that have lost methylation in the Nasonia lineage following gene duplication evolve more rapidly, show decreased median expression levels, and increased specialization in expression across development. Methylation of Nasonia genes signals constitutive transcription across developmental stages, whereas non-methylated genes show more dynamic developmental expression patterns. We speculate that loss of methylation may result in increased developmental specialization in evolution and acquisition of methylation may lead to broader constitutive expression.
Leo W Beukeboom - One of the best experts on this subject based on the ideXlab platform.
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Development of a Nasonia vitripennis outbred laboratory population for genetic analysis
Molecular ecology resources, 2013Co-Authors: Louis Van De Zande, Leo W Beukeboom, Steven Ferber, Ammerins De Haan, Joost Van Heerwaarden, Bart A. PannebakkerAbstract:The parasitoid wasp genus Nasonia has rapidly become a genetic model system for developmental and evolutionary biology. The release of its genome sequence led to the development of high-resolution genomic tools, for both interspecific and intraspecific research, which has resulted in great advances in understanding Nasonia biology. To further advance the utility of Nasonia vitripennis as a genetic model system and to be able to fully exploit the advantages of its fully sequenced and annotated genome, we developed a genetically variable and well-characterized experimental population. In this study, we describe the establishment of the genetically diverse HVRx laboratory population from strains collected from the field in the Netherlands. We established a maintenance method that retains genetic variation over generations of culturing in the laboratory. As a characterization of its genetic composition, we provide data on the standing genetic variation and estimate the effective population size (Ne) by microsatellite analysis. A genome-wide description of polymorphism is provided through pooled resequencing, which yielded 417 331 high-quality SNPs spanning all five Nasonia chromosomes. The HVRx population and its characterization are freely available as a community resource for investigators seeking to elucidate the genetic basis of complex trait variation using the Nasonia model system.
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cuticular hydrocarbon divergence in the jewel wasp Nasonia evolutionary shifts in chemical communication channels
Journal of Evolutionary Biology, 2013Co-Authors: Jan Buellesbach, John H. Werren, Rhitoban Raychoudhury, Leo W Beukeboom, Jürgen Gadau, Thomas Schmitt, Felix EchingerAbstract:The evolution and maintenance of intraspecific communication channels constitute a key feature of chemical signalling and sexual communication. However, how divergent chemical communication channels evolve while maintaining their integrity for both sender and receiver is poorly understood. In this study, we compare male and female cuticular hydrocarbon (CHC) profiles in the jewel wasp genus Nasonia, analyse their chemical divergence and investigate their role as species-specific sexual signalling cues. Males and females of all four Nasonia species showed unique, nonoverlapping CHC profiles unambiguously separating them. Surprisingly, male and female phylogenies based on the chemical distances between their CHC profiles differed dramatically, where only male CHC divergence parallels the molecular phylogeny of Nasonia. In particular, N. giraulti female CHC profiles were the most divergent from all other species and very different from its most closely related sibling species N. oneida. Furthermore, although our behavioural assays indicate that female CHC profiles can generally be perceived as sexual cues attracting males in Nasonia, this function has apparently been lost in the highly divergent female N. giraulti CHC profiles. Curiously, N. giraulti males are still attracted to heterospecific, but not to conspecific female CHC profiles. We suggest that this striking discrepancy has been caused by an extensive evolutionary shift in female N. giraulti CHC profiles, which are no longer used as conspecific recognition cues. Our study constitutes the first report of an apparent abandonment of a sexual recognition cue that the receiver did not adapt to.
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Circadian rhythms differ between sexes and closely related species of Nasonia wasps.
PloS one, 2013Co-Authors: Rinaldo C. Bertossa, Leo W Beukeboom, Jeroen Van Dijk, Wenwen Diao, David Saunders, Domien G. M. BeersmaAbstract:Activity rhythms in 24 h light-dark cycles, constant darkness, and constant light conditions were analyzed in four different Nasonia species for each sex separately. Besides similarities, clear differences are evident among and within Nasonia species as well as between sexes. In all species, activity in a light-dark cycle is concentrated in the photophase, typical for diurnal organisms. Contrary to most diurnal insect species so far studied, Nasonia follows Aschoff's rule by displaying long (>24 h) internal rhythms in constant darkness but short (
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circadian rhythms differ between sexes and closely related species of Nasonia wasps
PLOS ONE, 2013Co-Authors: Rinaldo C. Bertossa, Leo W Beukeboom, Jeroen Van Dijk, Wenwen Diao, David Saunders, Domien G. M. BeersmaAbstract:Activity rhythms in 24 h light-dark cycles, constant darkness, and constant light conditions were analyzed in four different Nasonia species for each sex separately. Besides similarities, clear differences are evident among and within Nasonia species as well as between sexes. In all species, activity in a light-dark cycle is concentrated in the photophase, typical for diurnal organisms. Contrary to most diurnal insect species so far studied, Nasonia follows Aschoff's rule by displaying long (>24 h) internal rhythms in constant darkness but short (<24 h) in constant light. In constant light, N. vitripennis males display robust circadian activity rhythms, whereas females are usually arrhythmic. In contrast to other Nasonia species, N. longicornis males display anticipatory activity, i.e. activity shortly before light-on in a light-dark cycle. As expected, N. oneida shows activity patterns similar to those of N. giraulti but with important differences in key circadian parameters. Differences in circadian activity patterns and parameters between species may reflect synchronization of specific life-history traits to environmental conditions. Scheduling mating or dispersion to a specific time of the day could be a strategy to avoid interspecific hybridization in Nasonia species that live in sympatry.
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Data from: Development of a Nasonia vitripennis outbred laboratory population for genetic analysis
2013Co-Authors: L. Van De Zande, Leo W Beukeboom, Steven Ferber, Ammerins De Haan, Joost Van Heerwaarden, Bart A. PannebakkerAbstract:The parasitoid wasp genus Nasonia has rapidly become a genetic model system for developmental and evolutionary biology. The release of its genome sequence led to the development of high-resolution genomic tools, for both interspecific and intraspecific research, which has resulted in great advances in understanding Nasonia biology. To further advance the utility of Nasonia vitripennis as a genetic model system and to be able to fully exploit the advantages of its fully sequenced and annotated genome, we developed a genetically variable and well-characterized experimental population. In this study, we describe the establishment of the genetically diverse HVRx laboratory population from strains collected from the field in the Netherlands. We established a maintenance method that retains genetic variation over generations of culturing in the laboratory. As a characterization of its genetic composition, we provide data on the standing genetic variation and estimate the effective population size (Ne) by microsatellite analysis. A genome-wide description of polymorphism is provided through pooled resequencing, which yielded 417 331 high-quality SNPs spanning all five Nasonia chromosomes. The HVRx population and its characterization are freely available as a community resource for investigators seeking to elucidate the genetic basis of complex trait variation using the Nasonia model system.
Gregory D D Hurst - One of the best experts on this subject based on the ideXlab platform.
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the hypercomplex genome of an insect reproductive parasite highlights the importance of lateral gene transfer in symbiont biology
Mbio, 2020Co-Authors: Crystal L. Frost, Alistair C Darby, Kayla C. King, Stefanos Siozios, Pol Nadaljimenez, Michael A Brockhurst, Gregory D D HurstAbstract:Mobile elements-plasmids and phages-are important components of microbial function and evolution via traits that they encode and their capacity to shuttle genetic material between species. We here report the unusually rich array of mobile elements within the genome of Arsenophonus Nasoniae, the son-killer symbiont of the parasitic wasp Nasonia vitripennis This microbe's genome has the highest prophage complement reported to date, with over 50 genomic regions that represent either intact or degraded phage material. Moreover, the genome is predicted to include 17 extrachromosomal genetic elements, which carry many genes predicted to be important at the microbe-host interface, derived from a diverse assemblage of insect-associated gammaproteobacteria. In our system, this diversity was previously masked by repetitive mobile elements that broke the assembly derived from short reads. These findings suggest that other complex bacterial genomes will be revealed in the era of long-read sequencing.IMPORTANCE The biology of many bacteria is critically dependent on genes carried on plasmid and phage mobile elements. These elements shuttle between microbial species, thus providing an important source of biological innovation across taxa. It has recently been recognized that mobile elements are also important in symbiotic bacteria, which form long-lasting interactions with their host. In this study, we report a bacterial symbiont genome that carries a highly complex array of these elements. Arsenophonus Nasoniae is the son-killer microbe of the parasitic wasp Nasonia vitripennis and exists with the wasp throughout its life cycle. We completed its genome with the aid of recently developed long-read technology. This assembly contained over 50 chromosomal regions of phage origin and 17 extrachromosomal elements within the genome, encoding many important traits at the host-microbe interface. Thus, the biology of this symbiont is enabled by a complex array of mobile elements.
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Genetic manipulation allows in vivo tracking of the life cycle of the son-killer symbiont, Arsenophonus Nasoniae, and reveals patterns of host invasion, tropism and pathology
'Wiley', 2019Co-Authors: Nadal-jimenez Pol, Frost, Crystal L., Griffin, Joanne S, Davies Lianne, Marcello Marco, Gregory D D HurstAbstract:Maternally heritable symbionts are common in arthropods and represent important partners and antagonists. A major impediment to understanding the mechanistic basis of these symbioses has been lack of genetic manipulation tools, for instance, those enabling transgenic GFP expression systems for in vivo visualization. Here, we transform the ‘son‐killer’ reproductive parasite Arsenophonus Nasoniae that infects the parasitic wasp Nasonia vitripennis with the plasmid pOM1‐gfp, re‐introduce this strain to N. vitripennis and then used this system to track symbiont life history in vivo. These data revealed transfer of the symbiont into the fly pupa by N. vitripennis during oviposition and N. vitripennis larvae developing infection over time through feeding. A strong tropism of A. Nasoniae to the N. vitripennis ovipositor developed during wasp pupation, which aids onward transmission. The symbiont was also visualized in diapause larvae. Occasional necrotic diapause larvae were observed which displayed intense systemic infection alongside widespread melanotic nodules indicative of an active but failed immune response. Our results provide the foundation for the study of this symbiosis through in vivo tracking of the fate of symbionts through host development, which is rarely achieved in heritable microbe/insect interactions
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Disentangling a Holobiont - Recent Advances and Perspectives in Nasonia Wasps
Frontiers in microbiology, 2016Co-Authors: Jessica Dittmer, J. Dylan Shropshire, Edward J. Van Opstal, Seth R Bordenstein, Gregory D D Hurst, Robert M BruckerAbstract:The parasitoid wasp genus Nasonia (Hymenoptera: Chalcidoidea) is a well-established model organism for insect development, evolutionary genetics, speciation and symbiosis. The host-microbiota assemblage which constitutes the Nasonia holobiont (a host together with all its associated microbes) consists of viruses, two heritable bacterial symbionts and a bacterial community dominated in abundance by a few taxa in the gut. In the wild, all four Nasonia species are systematically infected with the obligate intracellular bacterium Wolbachia and can additionally be co-infected with Arsenophonus Nasoniae. These two reproductive parasites have different transmission modes and host manipulations (cytoplasmic incompatibility vs. male-killing, respectively). Pioneering studies on Wolbachia in Nasonia demonstrated that closely-related Nasonia species harbor multiple and mutually incompatible Wolbachia strains, resulting in strong symbiont-mediated reproductive barriers that evolved early in the speciation process. Moreover, research on host-symbiont interactions and speciation has recently broadened from its historical focus on heritable symbionts to the entire microbial community. In this context, each Nasonia species hosts a distinguishable community of gut bacteria that experiences a temporal succession during host development and members of this bacterial community cause strong hybrid lethality during larval development. In this review, we present the Nasonia species complex as a model system to experimentally investigate questions regarding: (i) the impact of different microbes, including (but not limited to) heritable endosymbionts, on the extended phenotype of the holobiont, (ii) the establishment and regulation of a species-specific microbiota, (iii) the role of the microbiota in speciation, and (iv) the resilience and adaptability of the microbiota in wild populations subjected to different environmental pressures. We discuss the potential for easy microbiota manipulations in Nasonia as a promising experimental approach to address these fundamental aspects.
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Superparasitism Drives Heritable Symbiont Epidemiology and Host Sex Ratio in a Wasp
2016Co-Authors: Steven R. Parratt, Gregory D D Hurst, Crystal L. Frost, Martijn A. Schenkel, Annabel Rice, Kayla C. KingAbstract:Heritable microbial symbionts have profound impacts upon the biology of their arthropod hosts. Whilst our current understanding of the dynamics of these symbionts is typically cast within a framework of vertical transmission only, horizontal transmission has been observed in a number of cases. For instance, several symbionts can transmit horizontally when their parasitoid hosts share oviposition patches with uninfected conspecifics, a phenomenon called superparasitism. Despite this, horizontal transmission, and the host contact structures that facilitates it, have not been considered in heritable symbiont epidemiology. Here, we tested for the importance of host contact, and resulting horizontal transmission, for the epidemiology of a male-killing heritable symbiont (Arsenophonus Nasoniae) in parasitoid wasp hosts. We observed that host contact through superparasitism is necessary for this symbiont’s spread in populations of its primary host Nasonia vitripennis, such that when superparasitism rates are high, A. Nasoniae almost reaches fixation, causes highly female biased population sex ratios and consequently causes local host extinction. We further tested if natural interspecific variation in superparasitism behaviours predicted symbiont dynamics among parasitoid species. We found that A. Nasoniae was maintained in laboratory populations of a closely related set of Nasonia species, but declined in other, more distantly related pteromalid hosts. The natural proclivity of a species to superparasitise was the primary factor determining symbiont persistence. Our results thus indicate that host contact behaviour is a key factor for heritable microbe dynamics when horizontal transmission is possible, and that ‘reproductive parasite’ phenotypes, such as male-killing, may be of secondary importance in the dynamics of such symbiont infections.
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the draft genome sequence of arsenophonus Nasoniae son killer bacterium of Nasonia vitripennis reveals genes associated with virulence and symbiosis
Insect Molecular Biology, 2010Co-Authors: Timothy E Wilkes, John H. Werren, Alistair C Darby, Jeonghyeon Choi, John K Colbourne, Gregory D D HurstAbstract:Four percent of female Nasonia vitripennis carry the son-killer bacterium Arsenophonus Nasoniae, a microbe with notably different biology from other inherited parasites and symbionts. In this paper, we examine a draft genome sequence of the bacterium for open reading frames (ORFs), structures and pathways involved in interactions with its insect host. The genome data suggest that A. Nasoniae carries multiple type III secretion systems, and an array of toxin and virulence genes found in Photorhabdus, Yersinia and other gammaproteobacteria. Of particular note are ORFs similar to those known to affect host innate immune functioning in other bacteria, and four ORFs related to pro-apoptotic exotoxins. The genome sequences for both A. Nasoniae and its Nasonia host are useful tools for examining functional genomic interactions of microbial survival in hostile immune environments, and mechanisms of passage through gut epithelia, in a whole organism context.
Juergen Gadau - One of the best experts on this subject based on the ideXlab platform.
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Genetics of cuticular hydrocarbon differences between males of the parasitoid wasps Nasonia giraulti and Nasonia vitripennis.
Heredity, 2010Co-Authors: Oliver Niehuis, Thomas Schmitt, Andrea K. Judson, J. Büllesbach, Juergen GadauAbstract:Many insects rely on cuticular hydrocarbons (CHCs) as major recognition signals between individuals. Previous research on the genetics of CHCs has focused on Drosophila in which the roles of three desaturases and one elongase were highlighted. Comparable studies in other insect taxa have not been conducted so far. Here, we explore the genetics of CHCs in hybrids of the jewel wasps Nasonia giraulti and Nasonia vitripennis. We analyzed the CHC profiles of pure strain and of F2 hybrid males using gas chromatography coupled with mass spectrometry and distinguished 54 peaks, of which we identified 52 as straight-chain, monounsaturated, or methyl-branched CHCs. The latter compound class proved to be particularly abundant and diverse in Nasonia. Quantitative trait locus (QTL) analysis suggests fixed genetic differences between the two strains in 42 of the 54 studied traits, making Nasonia a promising genetic model for identifying genes involved in CHC biosynthesis. QTL for methyl-branched CHCs partly clustered in genomic regions with high recombination rate: a possible indication for pleiotropic genes that control their biosynthesis, which is largely unexplored so far. Finally, we identified and mapped genes in the Nasonia genome with high similarity to genes that have been implicated in alkene biosynthesis in Drosophila and discuss those that match in their position with predicted QTL for alkenes.
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the insect chemoreceptor superfamily of the parasitoid jewel wasp Nasonia vitripennis
Insect Molecular Biology, 2010Co-Authors: Hugh M Robertson, Juergen Gadau, Kevin W WannerAbstract:Chemoreception is important for locating food, mates and other resources in many insects, including the parasitoid jewel wasp Nasonia vitripennis. In the insect chemoreceptor superfamily, Nasonia has 58 gustatory receptor (Gr) genes, of which 11 are pseudogenes, leaving 47 apparently intact proteins encoded. No carbon dioxide receptors, two candidate sugar receptors, a DmGr43a orthologue, and several additional Gr lineages were identified, including significant gene subfamily expansions related to the 10 Grs found in the honey bee Apis mellifera. Nasonia has a total of 301 odorant receptor (Or) genes, of which 76 are pseudogenes, leaving 225 apparently intact Ors. Phylogenetic comparison with the 174 honey bee Ors reveals differential gene subfamily expansion in each hymenopteran lineage, along with a few losses from each species. The only simple orthologous relationship is the expected single DmOr83b orthologue. The large number of Nasonia Ors is the result of several major subfamily expansions, including one of 55 genes. Nasonia does not have the elaborate social chemical communication of honey bees, nor the diversity of floral odours honey bees detect, however, Nasonia wasps might need to detect a diversity of odours to find potential mates and hosts or avoid harmful substances in its environment.
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Phylogeography of Nasonia vitripennis (Hymenoptera) indicates a mitochondrial– Wolbachia sweep in North America
Heredity, 2010Co-Authors: Rhitoban Raychoudhury, John H. Werren, Bernd K. Grillenberger, Rudolf Bijlsma, Louis Van De Zande, Juergen Gadau, Leo W BeukeboomAbstract:Phylogeography of Nasonia vitripennis (Hymenoptera) indicates a mitochondrial– Wolbachia sweep in North America
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A comparison of recombination frequencies in intraspecific versus interspecific mapping populations of Nasonia
Heredity, 2010Co-Authors: Leo W Beukeboom, L. Van De Zande, Oliver Niehuis, Bart A. Pannebakker, T. Koevoets, Joshua D. Gibson, David M. Shuker, Juergen GadauAbstract:We present the first intraspecific linkage map for Nasonia vitripennis based on molecular markers. The map consists of 36 new microsatellite markers, extracted from the Nasonia genome sequence, and spans 515 cM. The five inferred linkage groups correspond to the five chromosomes of Nasonia. Comparison of recombination frequencies of the marker intervals spread over the whole genome (N=33 marker intervals) between the intraspecific N. vitripennis map and an interspecific N. vitripennis x N. giraulti map revealed a slightly higher (1.8%) recombination frequency in the intraspecific cross. We further considered an N. vitripennis x N. longicornis map with 29 microsatellite markers spanning 430 cM. Recom-bination frequencies in the two interspecific crosses differed neither between reciprocal crosses nor between mapping populations of embryos and adults. No major chromosomal rearrangements were found for the analyzed genomic segments. The observed differential F(2) hybrid male mortality has no significant effect on the genome-wide recombination frequency in Nasonia. We conclude that interspecific crosses between the different Nasonia species, a hallmark of Nasonia genetics, are generally suitable for mapping quantitative and qualitative trait loci for species differences. Heredity (2010) 104, 302-309; doi:10.1038/hdy.2009.185; published online 20 January 2010
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The distribution of microsatellites in the Nasonia parasitoid wasp genome
Insect Molecular Biology, 2010Co-Authors: Bart A. Pannebakker, Juergen Gadau, Oliver Niehuis, A. Hedley, David M. ShukerAbstract:Microsatellites are important molecular markers used in numerous genetic contexts. Despite this widespread use, the evolutionary processes governing microsatellite distribution and diversity remain controversial. Here, we present results on the distribution of microsatellites of three species in the parasitic wasp genus Nasonia generated by an in silico data-mining approach. Our results show that the overall microsatellite density in Nasonia is comparable to that of the honey bee, but much higher than in eight non-Hymenopteran arthropods. Across the Nasonia vitripennis genome, microsatellite density varied both within and amongst chromosomes. In contrast to other taxa, dinucleotides are the most abundant repeat type in all four species of Hymenoptera studied. Whether the differences between the Hymenoptera and other taxa are of functional significance remains to be determined.
Rhitoban Raychoudhury - One of the best experts on this subject based on the ideXlab platform.
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Asymmetric Assortative Mating Behaviour Reflects Incomplete Pre‐zygotic Isolation in the Nasonia Species Complex
Ethology, 2014Co-Authors: Jan Buellesbach, Rhitoban Raychoudhury, Christopher Greim, Thomas SchmittAbstract:Preference of con- over heterospecific mates leading to assortative mating can substantially contribute to pre-zygotic reproductive isolation and prevent fitness losses if post-zygotic hybridization barriers already exist. The jewel wasp genus Nasonia displays quite strong and well-studied post-zygotic reproductive isolation due to a ubiquitous Wolbachia infection causing cytoplasmic incompatibility between different species. Pre-zygotic isolation, however, has received far less research attention in this model organism, especially concerning the mechanisms and criteria of mate choice. In the present study, we analysed mate rejection and mate acceptance rates in cross-comparisons between all four Nasonia species. We put emphasis on observing which sex is more likely to interrupt interspecific matings and how discriminatory behaviour varies across the different species in all possible combinations. We found an asymmetric distribution of assortative mating among the four Nasonia species that appears to be highly influenced by the respective combinations of sex and species. Females appeared to be the main discriminators against heterospecific mating partners, but interestingly, we could also detect mate discrimination and rejection behaviour in males, a widely neglected factor in research on mating behaviour in general and on Nasonia in particular. Moreover, the asymmetry in the assortative mating behaviour was partially reflective of sym- or allopatric distributions of natural Nasonia populations.
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cuticular hydrocarbon divergence in the jewel wasp Nasonia evolutionary shifts in chemical communication channels
Journal of Evolutionary Biology, 2013Co-Authors: Jan Buellesbach, John H. Werren, Rhitoban Raychoudhury, Leo W Beukeboom, Jürgen Gadau, Thomas Schmitt, Felix EchingerAbstract:The evolution and maintenance of intraspecific communication channels constitute a key feature of chemical signalling and sexual communication. However, how divergent chemical communication channels evolve while maintaining their integrity for both sender and receiver is poorly understood. In this study, we compare male and female cuticular hydrocarbon (CHC) profiles in the jewel wasp genus Nasonia, analyse their chemical divergence and investigate their role as species-specific sexual signalling cues. Males and females of all four Nasonia species showed unique, nonoverlapping CHC profiles unambiguously separating them. Surprisingly, male and female phylogenies based on the chemical distances between their CHC profiles differed dramatically, where only male CHC divergence parallels the molecular phylogeny of Nasonia. In particular, N. giraulti female CHC profiles were the most divergent from all other species and very different from its most closely related sibling species N. oneida. Furthermore, although our behavioural assays indicate that female CHC profiles can generally be perceived as sexual cues attracting males in Nasonia, this function has apparently been lost in the highly divergent female N. giraulti CHC profiles. Curiously, N. giraulti males are still attracted to heterospecific, but not to conspecific female CHC profiles. We suggest that this striking discrepancy has been caused by an extensive evolutionary shift in female N. giraulti CHC profiles, which are no longer used as conspecific recognition cues. Our study constitutes the first report of an apparent abandonment of a sexual recognition cue that the receiver did not adapt to.
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Phylogeography of Nasonia vitripennis (Hymenoptera) indicates a mitochondrial– Wolbachia sweep in North America
Heredity, 2010Co-Authors: Rhitoban Raychoudhury, John H. Werren, Bernd K. Grillenberger, Rudolf Bijlsma, Louis Van De Zande, Juergen Gadau, Leo W BeukeboomAbstract:Phylogeography of Nasonia vitripennis (Hymenoptera) indicates a mitochondrial– Wolbachia sweep in North America
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Behavioral and genetic characteristics of a new species of Nasonia
Heredity, 2010Co-Authors: Rhitoban Raychoudhury, Bernd K. Grillenberger, Leo W Beukeboom, Christopher A. Desjardins, Jan Buellesbach, David W. Loehlin, Thomas Schmitt, John H. WerrenAbstract:Nasonia (Hymenoptera: Pteromalidae) is a genus of parasitoid wasps, which is fast emerging as a model system for evolutionary, genetic, developmental and host–endosymbiont interaction studies. In this study, we report a new species, Nasonia oneida, distinguish its behavioral, genetic and morphological features, and characterize its pre-mating and post-mating isolation with the other Nasonia species. Phylogenetic analyses indicate that N. oneida is the sister species to Nasonia giraulti with its own uniquely distinct cuticular hydrocarbon profiles, behavioral characteristics and subtle morphological differences. An important characteristic of N. oneida is the strong mate discrimination shown by the females against all the other Nasonia species. A genetic analysis of this phenotype by interspecies hybridization indicates that this strong discriminating phenotype is recessive. A formal species description of N. oneida Raychoudhury & Desjardins is also provided.
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rapidly evolving mitochondrial genome and directional selection in mitochondrial genes in the parasitic wasp Nasonia hymenoptera pteromalidae
Molecular Biology and Evolution, 2008Co-Authors: Deodoro C S G Oliveira, Rhitoban Raychoudhury, Dennis V. Lavrov, John H. WerrenAbstract:We sequenced the nearly complete mtDNA of 3 species of parasitic wasps, Nasonia vitripennis (2 strains), Nasonia giraulti, and Nasonia longicornis, including all 13 protein-coding genes and the 2 rRNAs, and found unusual patterns of mitochondrial evolution. The Nasonia mtDNA has a unique gene order compared with other insect mtDNAs due to multiple rearrangements. The mtDNAs of these wasps also show nucleotide substitution rates over 30 times faster than nuclear protein-coding genes, indicating among the highest substitution rates found in animal mitochondria (normally <10 times faster). A McDonald and Kreitman test shows that the between-species frequency of fixed replacement sites relative to silent sites is significantly higher compared with within-species polymorphisms in 2 mitochondrial genes of Nasonia, atp6 and atp8, indicating directional selection. Consistent with this interpretation, the Ka/Ks (nonsynonymous/synonymous substitution rates) ratios are higher between species than within species. In contrast, cox1 shows a signature of purifying selection for amino acid sequence conservation, although rates of amino acid substitutions are still higher than for comparable insects. The mitochondrial-encoded polypeptides atp6 and atp8 both occur in F0F1ATP synthase of the electron transport chain. Because malfunction in this fundamental protein severely affects fitness, we suggest that the accelerated accumulation of replacements is due to beneficial mutations necessary to compensate mild-deleterious mutations fixed by random genetic drift or Wolbachia sweeps in the fast evolving mitochondria of Nasonia. We further propose that relatively high rates of amino acid substitution in some mitochondrial genes can be driven by a “Compensation-Draft Feedback”; increased fixation of mildly deleterious mutations results in selection for compensatory mutations, which lead to fixation of additional deleterious mutations in nonrecombining mitochondrial genomes, thus accelerating the process of amino acid substitutions.
