Publications

sex determination in the hymenoptera.	the dominant and ancestral mode of sex determination in the hymenoptera is arrhenotokous parthenogenesis, in which diploid females develop from fertilized eggs and haploid males develop from unfertilized eggs. we discuss recent progress in the understanding of the genetic and cytoplasmic mechanisms that make arrhenotoky possible. the best-understood mode of sex determination in the hymenoptera is complementary sex determination (csd), in which diploid males are produced under conditions of inbre ...	2008	17803453
haploid females in the parasitic wasp nasonia vitripennis.	the insect order of hymenoptera (ants, bees, sawflies, and wasps) consists almost entirely of haplodiploid species. under haplodiploidy, males develop from unfertilized eggs and are haploid, whereas females develop from fertilized eggs and are diploid. although diploid males commonly occur, haploid females have never been reported. in analyzing the phenomenon of gynandromorphism in the parasitoid wasp nasonia vitripennis, we found a line that generates complete phenotypic females from unfertiliz ...	2007	17218519
characterization of phenoloxidase activity in venom from the ectoparasitoid nasonia vitripennis (walker) (hymenoptera: pteromalidae).	crude venom isolated from the ectoparasitic wasp nasonia vitripennis was found to possess phenoloxidase (po) activity. enzyme activity was detected by using a modified dot blot analysis approach in which venom samples were applied to nylon membranes and incubated with either l-dopa or dopamine. dot formation was most intense with dopamine as the substrate and no activators appeared to be necessary to evoke a melanization reaction. no melanization occurred when venom was incubated in schneider's ...	2007	17054979
wasps, beetles and the beginning of the ends.	recent papers investigating the genes regulating early embryogenesis in the wasp nasonia vitripennis and the beetle tribolium castaneum have provided us with important clues as to how early development is controlled in insects other than higher dipterans such as drosophila melanogaster. the results of these studies demonstrate that in insects that do not have bicoid, anterior patterning is regulated by a combination of maternal orthodenticle and hunchback. furthermore, during the evolution of lo ...	2006	16850399
[synanthropic flies (diptera: cyclorrapha) and their microhymenoptera parasitoids (insecta: hymenoptera) at monte mor poultry production system, são paulo, brazil].	a survey of synanthropic flies and their microhymenopteran parasitoids was conducted at the capuavinha poultry farm, municipality of monte mor, state of são paulo, brazil, from 1991 to 1992. bird manure samples were collected biweekly for examined and selected by the following methods: flotation in water, dissected pupae, and sentinel pupae. the species of flies more abundant were: chrysomya putoria (wiedeman) (41.2% - calliphoridae), muscidae: muscina stabulans( fallén) (27.3%), musca domestica ...	2006	16834896
the tripartite associations between bacteriophage, wolbachia, and arthropods.	by manipulating arthropod reproduction worldwide, the heritable endosymbiont wolbachia has spread to pandemic levels. little is known about the microbial basis of cytoplasmic incompatibility (ci) except that bacterial densities and percentages of infected sperm cysts associate with incompatibility strength. the recent discovery of a temperate bacteriophage (wo-b) of wolbachia containing ankyrin-encoding genes and virulence factors has led to intensifying debate that bacteriophage wo-b induces ci ...	2006	16710453
the origin of centrosomes in parthenogenetic hymenopteran insects.	a longstanding enigma has been the origin of maternal centrosomes that facilitate parthenogenetic development in hymenopteran insects. in young embryos, hundreds of microtubule-organizing centers (mtocs) are assembled completely from maternal components. two of these mtocs join the female pronucleus to set up the first mitotic spindle in unfertilized embryos and drive their development. these mtocs appear to be canonical centrosomes because they contain gamma-tubulin, cp190, and centrioles and t ...	2006	16631588
additional evidence for the genomic imprinting model of sex determination in the haplodiploid wasp nasonia vitripennis: isolation of biparental diploid males after x-ray mutagenesis.	the primary sex-determining signal in the haplodiploid wasp nasonia vitripennis is not known. in haplodiploid reproduction, unfertilized eggs typically develop into uniparental haploid males and fertilized eggs into biparental diploid females. although this reproductive strategy is common to all hymenoptera, sex-determination is not strictly specified by the number of genome copies inherited. furthermore, primary sex-determining signals differ among haplodiploid species. in the honeybee, for exa ...	2006	16552430
comparative venom toxicity between pteromalus puparum and nasonia vitripennis (hymenoptera: pteromalidae) toward the hemocytes of their natural hosts, non-target insects and cultured insect cells.	crude venoms from two parasitoid species, pteromalus puparum and nasonia vitripennis (hymenoptera: pteromalidae) were assayed for biological activities toward hemocytes from two species of their natural hosts and eight species of their non-natural hosts as well as two lines of cultured lepidoptera cells, respectively. by inhibiting the spreading and viability of insect hemocytes, the venom from p. puparum displayed significantly higher activities toward plasmatocytes and granular cells from both ...	2005	16026808
disruption of pupariation and eclosion behavior in the flesh fly, sarcophaga bullata parker (diptera: sarcophagidae), by venom from the ectoparasitic wasp nasonia vitripennis (walker) (hymenoptera: pteromalidae).	the action of venom from the ectoparasitic wasp, nasonia vitripennis, was monitored by examining alterations in patterned muscular movements characteristic of pupariation and eclosion behavior in the flesh fly, sarcophaga bullata. venom injected into larvae prior to pupariation caused a dose-dependent delay in pupariation. eventually, such larvae did pupariate, but puparia were abnormally formed. barographic records revealed that all elements of pupariation behavior were present in venom-injecte ...	2004	15378569
winter survival of nuisance fly parasitoids (hymenoptera: pteromalidae) in canada and denmark.	independent studies were performed in canada and in denmark to assess the survival of parasitic wasps (hymenoptera: pteromalidae) wintering in puparia of house fly, musca domestica linnaeus (diptera: muscidae). data in canada were collected for muscidifurax raptorgirault & saunders, m. raptorellus kogan & legner, m. zaraptor kogan & legner, nasonia vitripennis(walker), spalangia cameroni perkins, trichomalopsis sarcophagae (gahan) and urolepis rufipes (ashmead) in three microsites at an outdoor ...	2004	15301698
bacteriophage flux in endosymbionts (wolbachia): infection frequency, lateral transfer, and recombination rates.	the highly specialized genomes of bacterial endosymbionts typically lack one of the major contributors of genomic flux in the free-living microbial world-bacteriophages. this study yields three results that show bacteriophages have, to the contrary, been influential in the genome evolution of the most prevalent bacterial endosymbiont of invertebrates, wolbachia. first, we show that bacteriophage wo is more widespread in wolbachia than previously recognized, occurring in at least 89% (35/39) of t ...	2004	15254259
[parasitoids of chrysomya megacephala (fabricius) collected in itumbiara, goias, brazil].	this study determined the species of parasitoids associated with chrysomya megacephala, collected on bovine kidney baits, in itumbiara, state of goias, brazil. the pupae were obtained by flotation. they were individually placed in gelatin capsules until the emergence of the adult flies or their parasitoids. the overall prevalence of parasitism was 18.6%. brachymeria podagrica, nasonia vitripennis and pachycrepoideus vindemiae presented frequencies of 8.6%, 8.6% and 1.4%, respectively. this work ...	2004	15122391
[microhimenopteran parasitoids of chrysomya megacephala found in brazil].	the study was carried out with the purpose of identifying the main parasitoids of chrysomya megacephala in the city of rio de janeiro, brazil, given the importance of these flies as vectors of pathogenic agents in the urban environment. samplings were conducted every week from august 1999 to july 2000. the substrate used to grow fly pupae and to trap parasitoids was decomposing meat. it was identified three species of microhimenopterans: tachinaephagus zealandicus (encyrtidae), pachycrepoideus v ...	2003	14666314
temperature-related development of the parasitoid wasp nasonia vitripennis as forensic indicator.	development times of the forensically significant parasitic wasp nasonia vitripennis (walker) (hymenoptera: pteromalidae) from oviposition to pupation, and from oviposition to adult emergence, were studied in the laboratory at temperatures of 15-35 degrees c using host pupae of the blowfly protophormia terraenovae (robineau-desvoidy) (diptera: calliphoridae). total developmental time of n. vitripennis from oviposition to adult emergence (mean+/-sd) was 43.5+/-2.4, 22.5+/-1.1, 14.8+/-1.7 and 11.3 ...	2003	12941009
cold hardiness of the fly pupal parasitoid nasonia vitripennis is enhanced by its host sarcophaga crassipalpis.	supercooling points (scps) and low temperature survival were determined for diapausing and nondiapausing larvae of the ectoparasitoid nasonia vitripennis. neither nondiapausing nor diapausing larvae could survive tissue freezing. the scp profiles were nearly identical for nondiapause-destined (-27 degrees c) and diapausing larvae (-25 degrees c), but these values were not indicative of the lower limits of tolerance in either type of larvae: larvae were killed by chilling at temperatures well abo ...	2000	12770263
the ectoparasitic wasp nasonia vitripennis (walker) (hymenoptera: pteromalidae) differentially affects cells mediating the immune response of its flesh fly host, sarcophaga bullata parker (diptera: sarcophagidae).	in this study, we examined cellular immune responses in the flesh fly, sarcophaga bullata, when parasitized by the ectoparasitoid nasonia vitripennis. in unparasitized, young pharate adults and third instar, wandering larvae of s. bullata, four main hemocyte types were identified by light microscopy: plasmatocytes, granular cells, oenocytoids, and pro-hemocytes. parasitism of young pharate adults had a differential effect on host hemocytes; oenocytoids and pro-hemocytes appeared to be unaltered ...	2002	12770028
the jewel wasp nasonia: querying the genome with haplo-diploid genetics.	the jewel wasp nasonia vitripennis is considered the "drosophila melanogaster of the hymenoptera." this diminutive wasp offers insect geneticists a means for applying haplo-diploid genetics to the analysis of developmental processes. as in bees, haploid males develop from unfertilized eggs, while diploid females develop from fertilized eggs. nasonia's advantageous combination of haplo-diploid genetics and ease of handling in the laboratory facilitates screening the entire genome for recessive mu ...	2003	12640624
upregulation of transcripts encoding select heat shock proteins in the flesh fly sarcophaga crassipalpis in response to venom from the ectoparasitoid wasp nasonia vitripennis.		2002	12054789
role of delayed nuclear envelope breakdown and mitosis in wolbachia-induced cytoplasmic incompatibility.	the bacterium wolbachia manipulates reproduction in millions of insects worldwide; the most common effect is cytoplasmic incompatibility (ci). we found that ci resulted from delayed nuclear envelope breakdown of the male pronucleus in nasonia vitripennis. this caused asynchrony between the male and female pronuclei and, ultimately, loss of paternal chromosomes at the first mitosis. when wolbachia were present in the egg, synchrony was restored, which explains suppression of ci in these crosses. ...	2002	12004132
reciprocal inheritance of centrosomes in the parthenogenetic hymenopteran nasonia vitripennis.	in the majority of animals, the centrosome-the microtubule-organizing center of the cell-is assembled from components of both the sperm and the egg. how the males of the insect order hymenoptera acquire centrosomes is a mystery, as they originate from virgin birth.	2000	11102802
do wolbachia influence fecundity in nasonia vitripennis?	this paper reports the influence of a vertically transmitted symbiont, wolbachia, on host fitness in the parasitic wasp, nasonia vitripennis. we measured fecundities of uninfected strains and strains infected with either two wolbachia variants (wav,wbv) or one (wav or wbv). preliminary tests suggested that double-infected females produce more offspring on average than uninfected females. however, further studies failed to yield consistent fitness effects. to control for host genetic effects, the ...	2000	10692011
in vitro analysis of venom from the wasp nasonia vitripennis: susceptibility of different cell lines and venom-induced changes in plasma membrane permeability.	the lethal effects of crude venom prepared from the ectoparasitic wasp nasonia vitripennis were examined with cultured cells from six insect and two vertebrate species. venom caused cells from sarcophaga peregrina (nih sape4), drosophila melanogaster (crl 1963), trichoplusia ni (tn-368 and bti-tn-5b1-4), spodoptera frugiperda (sf-21ae), and lymantria dispar (ipl-ldfbc1) to round up, swell, and eventually die. despite similar sensitivities and overlapping lc50 values [0.0004-0.0015 venom reservoi ...	1999	10475265
extensive zygotic control of the anteroposterior axis in the wasp nasonia vitripennis.	insect axis formation is best understood in drosophila melanogaster, where rapid anteroposterior patterning of zygotic determinants is directed by maternal gene products. the earliest zygotic control is by gap genes, which determine regions of several contiguous segments and are largely conserved in insects. we have asked genetically whether early zygotic patterning genes control similar anteroposterior domains in the parasitoid wasp nasonia vitripennis as in drosophila. nasonia is advantageous ...	1999	9895318
effects of a and b wolbachia and host genotype on interspecies cytoplasmic incompatibility in nasonia.	wolbachia endosymbionts cause postmating reproductive isolation between the sibling species nasonia vitripennis and n. giraulti. most nasonia are doubly infected with a representative from each of the two major wolbachia groups (a and b). this study investigates the role of single (a or b) and double (a and b) wolbachia infections in interspecies cytoplasmic incompatibility (ci) and host genomic influences on the incompatibility phenotype. results show that the single a wolbachia harbored in n. ...	1998	9560398
in vitro culture and phylogenetic analysis of "candidatus arsenophonus triatominarum," an intracellular bacterium from the triatomine bug, triatoma infestans.	an intracellular symbiotic bacterium was isolated from the hemolymph of triatoma infestans and cultured in an aedes albopictus cell line. 16s ribosomal dna sequence analysis revealed that the bacterium was a member of the gamma-3 subgroup of the class proteobacteria, having 96.2% sequence identity with the most closely related bacterium, arsenophonus nasoniae, the causative agent of the son-killer trait in the parasitoid wasp nasonia vitripennis. these bacteria share morphological features and a ...	1997	9336921
pupal parasitoids (hymenoptera:pteromalidae) of filth flies (diptera:muscidae, calliphoridae) breeding in refuse and poultry and livestock manure in south korea.	five species of hymenopterous parasitoids were found parasitizing pupae of house flies, musca domestica l., in poultry and livestock facilities, refuse dump sites, and garbage dumpsters: spalangia nigroaenea curtis, s. nigra (latrielle), muscidifurax raptor girault & sanders, pachycrepoideus vindemiae (rondani), and nasonia vitripennis (walker). four hymenopterous parasitoids (s. nigroaenea, s. nigra, m. raptor and p. vindemiae) were recovered from the pupae of stable flies, stomoxys calcitrans ...	1997	9086716
distribution, prevalence and host associations of hymenoptera parasitic on calliphoridae occurring in flystrike in new zealand.	between 1920 and 1930, four species of parasitoid hymenoptera (tachinaephagus zealandicus, alysia manducator, nasonia vitripennis and brachymeria ucalegon) were imported to new zealand as an aid in the control of the blowflies causing myiasis in sheep (flystrike). their long-term effects have never been investigated and the extent to which they were successful in establishing and enlarging their ranges has been given scant regard over the last 60 years. a long-term epidemiological study of flyst ...	1996	8994139
single and double infections with wolbachia in the parasitic wasp nasonia vitripennis: effects on compatibility.	wolbachia are cytoplasmically inherited bacteria responsible for reproductive incompatibility in a wide range of insects. there has been little exploration, however, of within species wolbachia polymorphisms and their effects on compatibility. here we show that some strains of the parasitic wasp nasonia vitripennis are infected with two distinct bacterial strains (a and b) whereas others are singly infected (a or b). double and single infections are confirmed by both pcr amplification and southe ...	1996	8725242
studies on chrysomyia albiceps (wiedemann) one of the most important carrion flies in egypt.	chrysomyia albiceps often feeds to repletion and then regurgitates a portion of the food, a behaviour that heightens its importance as a mechanical vector of enteric pathogens. pupae of this fly are susceptible to the attack of the parasitic wasp, nasonia vitripennis in the laboratory as well as in nature at different underground depths where they pupate. the fly needs to feed on proteinaceous meals to start and complete its ovarian development. liver, beef, camel, chicken, rabbit and fish meat ...	1995	8586857
sequence relationship of retrotransposable elements r1 and r2 within and between divergent insect species.	r1 and r2 are retrotransposable elements that integrate at specific sites in the 28s ribosomal rna (rrna) genes of bombyx mori and drosophila melanogaster. we have previously shown that most insect species contain insertions in their 28s genes at the r1 and/or r2 site. we have sequenced the 3' half of r1 and r2 elements from three additional insect species: the fungus gnat, sciara coprophila (diptera); the japanese beetle, popillia japonica (colleoptera); and the parasitic wasp, nasonia vitripen ...	1993	8383793
toxicity of the venom from nasonia vitripennis (hymenoptera: pteromalidae) toward fly hosts, nontarget insects, different developmental stages, and cultured insect cells.	a venom preparation from nasonia vitripennis, a wasp ectoparasitoid of fly pupae, was assayed for lethality in different stages of insects representing ten different orders and in cultured insect cells. in most cases, the motor activity of the injected insects remained completely normal for 1-2 days after the injection and displayed none of the symptoms of paralysis commonly reported for venoms of the hymenoptera. a natural host, the flesh fly sarcophaga bullata, was highly sensitive in the pupa ...	1993	8342173
[the occurrence of puparium parasitoids as natural enemies of house flies].	investigations on the pupal parasitoid complex of the house fly musca domestica l. and its seasonal occurrence were carried out, mainly in the land brandenburg, during 1987-1990. samples of about 500-1,500 puparia were collected at irregular from composted calf dung at ruhlsdorf, a pig farm at wittbrietzen, and from straw calf bedding at beelitz. the rates of parasitism varied considerably between seasons and years, as well as stable types and dung managements. the highest level of parasitism wa ...	1994	8173583
a prokaryotic dnaa sequence in drosophila melanogaster: wolbachia infection and cytoplasmic incompatibility among laboratory strains.	using oligonucleotide primers derived from the aligned polypeptide sequences of several prokaryotic dnaa genes, we amplified from drosophila melanogaster dna a 557 bp fragment containing a single open reading frame. the predicted peptide sequence shows a significant similarity to previously characterized protein sequences that are encoded by the dnaa genes of several prokaryotes. the dnaa sequences are also detectable by pcr in dna from drosophila simulans and nasonia vitripennis flies which are ...	1994	7894745
sequence analysis of the d1 and d2 regions of 28s rdna in the hornet (vespa crabro) (hymenoptera, vespinae).	the two variable domains d1 and d2 near the 5' end of the 28s ribosomal rna gene (large subunit rrna) have been sequenced for vespa crabro. the sequence was aligned to corresponding rdna regions of the wasp species nasonia vitripennis, melittobia digitata and the fruit fly drosophila melanogaster. we analysed the nucleotide composition and sequence similarity for the different regions of the investigated sequences and present the inferred secondary structure of vespa crabro.	1994	7704312
induction of paternal genome loss by the paternal-sex-ratio chromosome and cytoplasmic incompatibility bacteria (wolbachia): a comparative study of early embryonic events.	paternal genome loss (pgl) during early embryogenesis is caused by two different genetic elements in the parasitoid wasp, nasonia vitripennis. paternal sex ratio (psr) is a paternally inherited supernumerary chromosome that disrupts condensation of the paternal chromosomes by the first mitotic division of fertilized eggs. bacteria belonging to the genus wolbachia are present in nasonia eggs and also disrupt paternal chromosome condensation in crosses between cytoplasmically incompatible strains. ...	1995	7598906
host-feeding and oviposition on musca domestica by spalangia cameroni, nasonia vitripennis, and muscidifurax raptor (hymenoptera: pteromalidae) influences their longevity and fecundity.		1967	6025086
paternal transmission of an extrachromosomal factor in a wasp: evolutionary implications.	females of the haplodiploid wasp, nasonia vitripennis, lay both fertilised eggs (= female) and unfertilised eggs (= male) following matings with ordinary males. matings with males that carry the extrachromosomal paternal-sex-ratio (psr) factor result in the production of all-male broods. these male offspring are haploid and inherit only the maternal genome, yet some also inherit the psr factor. the proportion of males inheriting psr is highly correlated with the proportion of eggs fertilised in ...	2013	3610659
susceptibility of house flies (diptera: muscidae) and five pupal parasitoids (hymenoptera: pteromalidae) to abamectin and seven commercial insecticides.	assays of five commercial insecticides applied as residual sprays at label rates to plywood indicated the most toxic insecticide overall for pteromalid parasitoids of house flies, musca domestica l., was atroban (permethrin), followed by ciodrin (crotoxyphos), rabon (tetrachlorvinphos), ectrin (fenvalerate), and cygon (dimethoate). insecticide-susceptible house flies were susceptible to all five insecticides (mortality, 62-100%). flies that were recently colonized from populations on dairy farms ...	1992	1593014
effects of deletions on mitotic stability of the paternal-sex-ratio (psr) chromosome from nasonia.	paternal-sex-ratio (psr) is a b chromosome that causes all-male offspring in the parasitoid wasp nasonia vitripennis. it is only transmitted via sperm of carrier males and destroys the other paternal chromosomes during the first mitotic division of the fertilized egg. because of haplodiploidy, the effect of psr is to convert diploid (female) eggs into haploid eggs that develop into psr-bearing males. the psr chromosome was previously found to contain several families of repetitive dna, which app ...	2005	1291226
the effect of diet on the ultrastructure of the mid-gut cells of nasonia vitripennis (walk.) (insecta: hymenoptera) at various ages.	the ultrastructure of mid-gut cells of female nasonia fed on a diet of 10% sterile sucrose is described. there are extensive alterations in cell organelles, particularly the mitochondria, rough endoplasmic reticulum (r.e.r.) and lipid inclusions, when compared to similar insects fed a normal diet of dipteran pupae. a proportion of the mitochondria found in the apical cell region are enlarged in size and contain electron-dense granules. the remaining mitochondria are smaller, but also contain ele ...	1994	201382