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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 of the Parasitoid Wasp diachasma alloeum an emerging model for ecological speciation and transitions to asexual reproduction
Genome Biology and Evolution, 2019Co-Authors: John H Werren, Eric S Tvedte, Kimberly K O Walden, Kyle E Mcelroy, Andrew A Forbes, Glen R Hood, John M Logsdon, Jeffrey L Feder, Hugh M RobertsonAbstract:Parasitoid Wasps are among the most speciose animals, yet have relatively few available genomic resources. We report a draft genome assembly of the Wasp Diachasma alloeum (Hymenoptera: Braconidae), a host-specific Parasitoid of the apple maggot fly Rhagoletis pomonella (Diptera: Tephritidae), and a developing model for understanding how ecological speciation can "cascade" across trophic levels. Identification of gene content confirmed the overall quality of the draft genome, and we manually annotated ∼400 genes as part of this study, including those involved in oxidative phosphorylation, chemosensation, and reproduction. Through comparisons to model hymenopterans such as the European honeybee Apis mellifera and Parasitoid Wasp Nasonia vitripennis, as well as a more closely related braconid Parasitoid Microplitis demolitor, we identified a proliferation of transposable elements in the genome, an expansion of chemosensory genes in Parasitoid Wasps, and the maintenance of several key genes with known roles in sexual reproduction and sex determination. The D. alloeum genome will provide a valuable resource for comparative genomics studies in Hymenoptera as well as specific investigations into the genomic changes associated with ecological speciation and transitions to asexuality.
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Parasitoid Wasp venom elevates sorbitol and alters expression of metabolic genes in human kidney cells
Toxicon, 2019Co-Authors: Aisha L Siebert, Luticha A Doucette, Patricia J Simpsonhaidaris, John H WerrenAbstract:Venom from the Parasitoid Wasp Nasonia vitripennis dramatically elevates sorbitol levels in its natural fly hosts. In humans, sorbitol elevation is associated with complications of diabetes. Here we demonstrate that venom also induces this disease-relevant phenotype in human cells, and investigate possible pathways involved. Key findings are that (a) low doses of Nasonia venom elevate sorbitol levels in human renal mesangial cells (HRMCs) without changing glucose or fructose levels; (b) venom is a much more potent inducer of sorbitol elevation than glucose; (c) low venom doses significantly alter expression of genes involved in sterol and alcohol metabolism, transcriptional regulation, and chemical/stimulus response; (d) although venom treatment does not alter expression of the key sorbitol pathway gene aldose reductase (AR); (e) venom elevates expression of a related gene implicated in diabetes complications (AKR1C3) as well as the fructose metabolic gene (GFPT2). Although elevated sorbitol is accepted as a major contributor to secondary complications of diabetes, the molecular mechanism of sorbitol regulation and its contribution to diabetes complications are not fully understood. Our findings suggest that genes other than AR could contribute to sorbitol regulation, and more broadly illustrate the potential of Parasitoid venoms for medical application.
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phylogeny of cytoplasmic incompatibility microorganisms in the Parasitoid Wasp genus nasonia hymenoptera pteromalidae based on 16s ribosomal dna sequences
Insect Molecular Biology, 1992Co-Authors: J A J Breeuwer, William G Weisburg, Richard Stouthamer, Susan M Barns, Dale A Pelletier, John H WerrenAbstract:Cytoplasmic incompatibility results in embryo mortality in diploids, or all male offspring in haplodiploids, when individuals carrying different cytoplasmic factors are crossed. Cytoplasmic factors have been identified as intracellular micro-organisms. Microbeinduced cytoplasmic incompatibility is found in many insect taxa and may play a role in reproductive isolation between populations. Such micro-organisms cause bidirectional incompatibility between species of the Parasitoid Wasp genus Nasonia. The phylogenetic relationship of cytoplasmic incompatibility microorganisms (CIM) of different Nasonia species was analysed using their 16S ribosomal DNA (rDNA) sequence. Two 16S rDNA operons were detected in the CIM of each Nasonia species. Sequence analysis indicates that the Nasonia CIM are closely related and belong to the alpha group of the Proteobacteria.
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phylogeny of cytoplasmic incompatibility micro organisms in the Parasitoid Wasp genus nasonia hymenoptera pteromalidae based on 16s ribosomal dna sequences
Insect Molecular Biology, 1992Co-Authors: J A J Breeuwer, William G Weisburg, Richard Stouthamer, Susan M Barns, Dale A Pelletier, John H WerrenAbstract:Cytoplasmic incompatibility results in embryo mortality in diploids, or all male offspring in haplodiploids, when individuals carrying different cytoplasmic factors are crossed. Cytoplasmic factors have been identified as intracellular micro-organisms. Microbeinduced cytoplasmic incompatibility is found in many insect taxa and may play a role in reproductive isolation between populations. Such micro-organisms cause bidirectional incompatibility between species of the Parasitoid Wasp genus Nasonia. The phylogenetic relationship of cytoplasmic incompatibility microorganisms (CIM) of different Nasonia species was analysed using their 16S ribosomal DNA (rDNA) sequence. Two 16S rDNA operons were detected in the CIM of each Nasonia species. Sequence analysis indicates that the Nasonia CIM are closely related and belong to the alpha group of the Proteobacteria.
Todd A Schlenke - One of the best experts on this subject based on the ideXlab platform.
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Parasitoid Wasp venom serca regulates drosophila calcium levels and inhibits cellular immunity
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Nathan T. Mortimer, Jeremy Goecks, Balint Z Kacsoh, Gregory J Bowersock, James A. Mobley, James Taylor, Todd A SchlenkeAbstract:Because parasite virulence factors target host immune responses, identification and functional characterization of these factors can provide insight into poorly understood host immune mechanisms. The fruit fly Drosophila melanogaster is a model system for understanding humoral innate immunity, but Drosophila cellular innate immune responses remain incompletely characterized. Fruit flies are regularly infected by Parasitoid Wasps in nature and, following infection, flies mount a cellular immune response culminating in the cellular encapsulation of the Wasp egg. The mechanistic basis of this response is largely unknown, but Wasps use a mixture of virulence proteins derived from the venom gland to suppress cellular encapsulation. To gain insight into the mechanisms underlying Wasp virulence and fly cellular immunity, we used a joint transcriptomic/proteomic approach to identify venom genes from Ganaspis sp.1 (G1), a previously uncharacterized Drosophila Parasitoid species, and found that G1 venom contains a highly abundant sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. Accordingly, we found that fly immune cells termed plasmatocytes normally undergo a cytoplasmic calcium burst following infection, and that this calcium burst is required for activation of the cellular immune response. We further found that the plasmatocyte calcium burst is suppressed by G1 venom in a SERCA-dependent manner, leading to the failure of plasmatocytes to become activated and migrate toward G1 eggs. Finally, by genetically manipulating plasmatocyte calcium levels, we were able to alter fly immune success against G1 and other Parasitoid species. Our characterization of Parasitoid Wasp venom proteins led us to identify plasmatocyte cytoplasmic calcium bursts as an important aspect of fly cellular immunity.
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Parasitoid Wasp venom serca regulates drosophila calcium levels and inhibits cellular immunity
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Nathan T. Mortimer, Jeremy Goecks, Balint Z Kacsoh, Gregory J Bowersock, James A. Mobley, James Taylor, Todd A SchlenkeAbstract:Because parasite virulence factors target host immune responses, identification and functional characterization of these factors can provide insight into poorly understood host immune mechanisms. The fruit fly Drosophila melanogaster is a model system for understanding humoral innate immunity, but Drosophila cellular innate immune responses remain incompletely characterized. Fruit flies are regularly infected by Parasitoid Wasps in nature and, following infection, flies mount a cellular immune response culminating in the cellular encapsulation of the Wasp egg. The mechanistic basis of this response is largely unknown, but Wasps use a mixture of virulence proteins derived from the venom gland to suppress cellular encapsulation. To gain insight into the mechanisms underlying Wasp virulence and fly cellular immunity, we used a joint transcriptomic/proteomic approach to identify venom genes from Ganaspis sp.1 (G1), a previously uncharacterized Drosophila Parasitoid species, and found that G1 venom contains a highly abundant sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. Accordingly, we found that fly immune cells termed plasmatocytes normally undergo a cytoplasmic calcium burst following infection, and that this calcium burst is required for activation of the cellular immune response. We further found that the plasmatocyte calcium burst is suppressed by G1 venom in a SERCA-dependent manner, leading to the failure of plasmatocytes to become activated and migrate toward G1 eggs. Finally, by genetically manipulating plasmatocyte calcium levels, we were able to alter fly immune success against G1 and other Parasitoid species. Our characterization of Parasitoid Wasp venom proteins led us to identify plasmatocyte cytoplasmic calcium bursts as an important aspect of fly cellular immunity.
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defence strategies against a Parasitoid Wasp in drosophila fight or flight
Biology Letters, 2012Co-Authors: Thierry Lefevre, Balint Z Kacsoh, Jacobus C De Roode, Todd A SchlenkeAbstract:Hosts may defend themselves against parasitism through a wide variety of defence mechanisms, but due to finite resources, investment in one defence mechanism may trade-off with investment in another mechanism. We studied resistance strategies against the Parasitoid Wasp Leptopilina boulardi in two Drosophila species. We found that D. melanogaster had significantly lower physiological resistance against L. boulardi than D. simulans , and hypothesized that D. melanogaster might instead invest more heavily in other forms of defence, such as behavioural defence. We found that when given a choice between clean oviposition sites and sites infested with Wasps, both D. melanogaster and D. simulans detected and avoided infested sites, which presumably limits later exposure of their offspring to infection. Unlike D. simulans , however, D. melanogaster laid significantly fewer eggs than controls in the forced presence of Wasps. Our findings suggest that D. melanogaster relies more heavily on behavioural avoidance as defence against Wasp parasitism than D. simulans , and that this may compensate for a lack of physiological defence.
David M. Shuker - One of the best experts on this subject based on the ideXlab platform.
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genomics of sex allocation in the Parasitoid Wasp nasonia vitripennis
BMC Genomics, 2020Co-Authors: Nicola Cook, Joost Van Den Heuvel, David M. ShukerAbstract:Whilst adaptive facultative sex allocation has been widely studied at the phenotypic level across a broad range of organisms, we still know remarkably little about its genetic architecture. Here, we explore the genome-wide basis of sex ratio variation in the Parasitoid Wasp Nasonia vitripennis, perhaps the best studied organism in terms of sex allocation, and well known for its response to local mate competition. We performed a genome-wide association study (GWAS) for single foundress sex ratios using iso-female lines derived from the recently developed outbred N. vitripennis laboratory strain HVRx. The iso-female lines capture a sample of the genetic variation in HVRx and we present them as the first iteration of the Nasonia vitripennis Genome Reference Panel (NVGRP 1.0). This panel provides an assessment of the standing genetic variation for sex ratio in the study population. Using the NVGRP, we discovered a cluster of 18 linked SNPs, encompassing 9 annotated loci associated with sex ratio variation. Furthermore, we found evidence that sex ratio has a shared genetic basis with clutch size on three different chromosomes. Our approach provides a thorough description of the quantitative genetic basis of sex ratio variation in Nasonia at the genome level and reveals a number of inter-related candidate loci underlying sex allocation regulation.
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genomics of sex allocation in the Parasitoid Wasp nasonia vitripennis
bioRxiv, 2020Co-Authors: Nicola Cook, Joost Van Den Heuvel, David M. ShukerAbstract:Background: Whilst adaptive facultative sex allocation has been widely studied at the phenotypic level across a broad range of organisms, we still know remarkably little about its genetic architecture. Here, we explore the genome-wide basis of sex ratio variation in the Parasitoid Wasp Nasonia vitripennis, perhaps the best studied organism in terms of sex allocation, and well known for its response to local mate competition (LMC). Results: We performed a genome-wide association study (GWAS) for single foundress sex ratios using iso-female lines derived from the recently developed outbred N. vitripennis laboratory strain HVRx. The iso-female lines capture a sample of the genetic variation in HVRx and we present them as the first iteration of the Nasonia vitripennis Genome Reference Panel (NVGRP 1.0). This panel provides an assessment of the standing genetic variation for sex ratio in the study population. Using the NVGRP, we discovered a cluster of 18 linked SNPs, encompassing 9 annotated loci associated with sex ratio variation. Furthermore, we found evidence that sex ratio has a shared genetic basis with clutch size on three different chromosomes. Conclusions: Our approach provides a thorough description of the quantitative genetic basis of sex ratio variation in Nasonia at the genome level and reveals a number of inter-related candidate loci underlying sex allocation regulation.
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the transcriptomic basis of oviposition behaviour in the Parasitoid Wasp nasonia vitripennis
PLOS ONE, 2013Co-Authors: Urmi Trivedi, Mark Blaxter, Rebekah Watt, David M. ShukerAbstract:Linking behavioural phenotypes to their underlying genotypes is crucial for uncovering the mechanisms that underpin behaviour and for understanding the origins and maintenance of genetic variation in behaviour. Recently, interest has begun to focus on the transcriptome as a route for identifying genes and gene pathways associated with behaviour. For many behavioural traits studied at the phenotypic level, we have little or no idea of where to start searching for “candidate” genes: the transcriptome provides such a starting point. Here we consider transcriptomic changes associated with oviposition in the Parasitoid Wasp Nasonia vitripennis. Oviposition is a key behaviour for Parasitoids, as females are faced with a variety of decisions that will impact offspring fitness. These include choosing between hosts of differing quality, as well as making decisions regarding clutch size and offspring sex ratio. We compared the whole-body transcriptomes of resting or ovipositing female Nasonia using a “DeepSAGE” gene expression approach on the Illumina sequencing platform. We identified 332 tags that were significantly differentially expressed between the two treatments, with 77% of the changes associated with greater expression in resting females. Oviposition therefore appears to focus gene expression away from a number of physiological processes, with gene ontologies suggesting that aspects of metabolism may be down-regulated during egg-laying. Nine of the most abundant differentially expressed tags showed greater expression in ovipositing females though, including the genes purity-of-essence (associated with behavioural phenotypes in Drosophila) and glucose dehydrogenase (GLD). The GLD protein has been implicated in sperm storage and release in Drosophila and so provides a possible candidate for the control of sex allocation by female Nasonia during oviposition. Oviposition in Nasonia therefore clearly modifies the transcriptome, providing a starting point for the genetic dissection of oviposition.
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Sexual selection on male development time in the Parasitoid Wasp Nasonia vitripennis.
Journal of evolutionary biology, 2011Co-Authors: A. M. Moynihan, David M. ShukerAbstract:Mating systems are shaped by a species’ ecology, which sets the stage for sexual selection. Males of the gregarious Parasitoid Wasp Nasonia vitripennis compete to mate virgin females at the natal site, before females disperse. Males could increase their fitness by being larger and monopolizing female emergence sites or by emerging earlier pre-empting access to females. We consider sexual selection on male body size and development time in Nasonia, and a potential trade-off between the two traits. We explored sex-specific patterns of larval and pupal development, finding that smaller Wasps developed slower than their host-mates. Using competition experiments between brothers, we found that earlier eclosing males mated more females independently of absolute and relative body size. Our data explain the lack of relationship between fitness and body size in male Nasonia and reinforce the importance of protandry in mating systems where access to mates is time-limited.
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Effects of Spontaneous Mutation Accumulation on Sex Ratio Traits in a Parasitoid Wasp
Evolution; international journal of organic evolution, 2008Co-Authors: Bart A. Pannebakker, David M. Shuker, Daniel L Halligan, K. Tracy Reynolds, Gavin A. Ballantyne, Nicholas H. Barton, Stuart A. WestAbstract:Sex allocation theory has proved extremely successful at predicting when individuals should adjust the sex of their offspring in response to environmental conditions. However, we know rather little about the underlying genetics of sex ratio or how genetic architecture might constrain adaptive sex-ratio behavior. We examined how mutation influenced genetic variation in the sex ratios produced by the Parasitoid Wasp Nasonia vitripennis. In a mutation accumulation experiment, we determined the mutability of sex ratio, and compared this with the amount of genetic variation observed in natural populations. We found that the mutability (h(2)(m)) ranges from 0.001 to 0.002, similar to estimates for life-history traits in other organisms. These estimates suggest one mutation every 5-60 generations, which shift the sex ratio by approximately 0.01 (proportion males). In this and other studies, the genetic variation in N. vitripennis sex ratio ranged from 0.02 to 0.17 (broad-sense heritability, H(2)). If sex ratio is maintained by mutation-selection balance, a higher genetic variance would be expected given our mutational parameters. Instead, the observed genetic variance perhaps suggests additional selection against sex-ratio mutations with deleterious effects on other fitness traits as well as sex ratio (i.e., pleiotropy), as has been argued to be the case more generally.
J A J Breeuwer - One of the best experts on this subject based on the ideXlab platform.
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phylogeny of cytoplasmic incompatibility microorganisms in the Parasitoid Wasp genus nasonia hymenoptera pteromalidae based on 16s ribosomal dna sequences
Insect Molecular Biology, 1992Co-Authors: J A J Breeuwer, William G Weisburg, Richard Stouthamer, Susan M Barns, Dale A Pelletier, John H WerrenAbstract:Cytoplasmic incompatibility results in embryo mortality in diploids, or all male offspring in haplodiploids, when individuals carrying different cytoplasmic factors are crossed. Cytoplasmic factors have been identified as intracellular micro-organisms. Microbeinduced cytoplasmic incompatibility is found in many insect taxa and may play a role in reproductive isolation between populations. Such micro-organisms cause bidirectional incompatibility between species of the Parasitoid Wasp genus Nasonia. The phylogenetic relationship of cytoplasmic incompatibility microorganisms (CIM) of different Nasonia species was analysed using their 16S ribosomal DNA (rDNA) sequence. Two 16S rDNA operons were detected in the CIM of each Nasonia species. Sequence analysis indicates that the Nasonia CIM are closely related and belong to the alpha group of the Proteobacteria.
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phylogeny of cytoplasmic incompatibility micro organisms in the Parasitoid Wasp genus nasonia hymenoptera pteromalidae based on 16s ribosomal dna sequences
Insect Molecular Biology, 1992Co-Authors: J A J Breeuwer, William G Weisburg, Richard Stouthamer, Susan M Barns, Dale A Pelletier, John H WerrenAbstract:Cytoplasmic incompatibility results in embryo mortality in diploids, or all male offspring in haplodiploids, when individuals carrying different cytoplasmic factors are crossed. Cytoplasmic factors have been identified as intracellular micro-organisms. Microbeinduced cytoplasmic incompatibility is found in many insect taxa and may play a role in reproductive isolation between populations. Such micro-organisms cause bidirectional incompatibility between species of the Parasitoid Wasp genus Nasonia. The phylogenetic relationship of cytoplasmic incompatibility microorganisms (CIM) of different Nasonia species was analysed using their 16S ribosomal DNA (rDNA) sequence. Two 16S rDNA operons were detected in the CIM of each Nasonia species. Sequence analysis indicates that the Nasonia CIM are closely related and belong to the alpha group of the Proteobacteria.
Nathan T. Mortimer - One of the best experts on this subject based on the ideXlab platform.
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Parasitoid Wasp venom serca regulates drosophila calcium levels and inhibits cellular immunity
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Nathan T. Mortimer, Jeremy Goecks, Balint Z Kacsoh, Gregory J Bowersock, James A. Mobley, James Taylor, Todd A SchlenkeAbstract:Because parasite virulence factors target host immune responses, identification and functional characterization of these factors can provide insight into poorly understood host immune mechanisms. The fruit fly Drosophila melanogaster is a model system for understanding humoral innate immunity, but Drosophila cellular innate immune responses remain incompletely characterized. Fruit flies are regularly infected by Parasitoid Wasps in nature and, following infection, flies mount a cellular immune response culminating in the cellular encapsulation of the Wasp egg. The mechanistic basis of this response is largely unknown, but Wasps use a mixture of virulence proteins derived from the venom gland to suppress cellular encapsulation. To gain insight into the mechanisms underlying Wasp virulence and fly cellular immunity, we used a joint transcriptomic/proteomic approach to identify venom genes from Ganaspis sp.1 (G1), a previously uncharacterized Drosophila Parasitoid species, and found that G1 venom contains a highly abundant sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. Accordingly, we found that fly immune cells termed plasmatocytes normally undergo a cytoplasmic calcium burst following infection, and that this calcium burst is required for activation of the cellular immune response. We further found that the plasmatocyte calcium burst is suppressed by G1 venom in a SERCA-dependent manner, leading to the failure of plasmatocytes to become activated and migrate toward G1 eggs. Finally, by genetically manipulating plasmatocyte calcium levels, we were able to alter fly immune success against G1 and other Parasitoid species. Our characterization of Parasitoid Wasp venom proteins led us to identify plasmatocyte cytoplasmic calcium bursts as an important aspect of fly cellular immunity.
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Parasitoid Wasp venom serca regulates drosophila calcium levels and inhibits cellular immunity
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Nathan T. Mortimer, Jeremy Goecks, Balint Z Kacsoh, Gregory J Bowersock, James A. Mobley, James Taylor, Todd A SchlenkeAbstract:Because parasite virulence factors target host immune responses, identification and functional characterization of these factors can provide insight into poorly understood host immune mechanisms. The fruit fly Drosophila melanogaster is a model system for understanding humoral innate immunity, but Drosophila cellular innate immune responses remain incompletely characterized. Fruit flies are regularly infected by Parasitoid Wasps in nature and, following infection, flies mount a cellular immune response culminating in the cellular encapsulation of the Wasp egg. The mechanistic basis of this response is largely unknown, but Wasps use a mixture of virulence proteins derived from the venom gland to suppress cellular encapsulation. To gain insight into the mechanisms underlying Wasp virulence and fly cellular immunity, we used a joint transcriptomic/proteomic approach to identify venom genes from Ganaspis sp.1 (G1), a previously uncharacterized Drosophila Parasitoid species, and found that G1 venom contains a highly abundant sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. Accordingly, we found that fly immune cells termed plasmatocytes normally undergo a cytoplasmic calcium burst following infection, and that this calcium burst is required for activation of the cellular immune response. We further found that the plasmatocyte calcium burst is suppressed by G1 venom in a SERCA-dependent manner, leading to the failure of plasmatocytes to become activated and migrate toward G1 eggs. Finally, by genetically manipulating plasmatocyte calcium levels, we were able to alter fly immune success against G1 and other Parasitoid species. Our characterization of Parasitoid Wasp venom proteins led us to identify plasmatocyte cytoplasmic calcium bursts as an important aspect of fly cellular immunity.
