Publications

a wolbachia symbiont in aedes aegypti limits infection with dengue, chikungunya, and plasmodium.	wolbachia are maternally inherited intracellular bacterial symbionts that are estimated to infect more than 60% of all insect species. while wolbachia is commonly found in many mosquitoes it is absent from the species that are considered to be of major importance for the transmission of human pathogens. the successful introduction of a life-shortening strain of wolbachia into the dengue vector aedes aegypti that halves adult lifespan has recently been reported. here we show that this same wolbac ...	2009	20064373
taxonomic boundaries, phylogenetic relationships and biogeography of the drosophila willistoni subgroup (diptera: drosophilidae).	the drosophila willistoni subgroup represents a complex with varying taxonomic levels. it encompasses d. willistoni and its five sibling species: d. equinoxialis, d. insularis, d. paulistorum, d. pavlovskiana and d. tropicalis. of these, d. equinoxialis, d. tropicalis and d. willistoni present differentiation at subspecific level, whereas d. paulistorum represents a superspecies, formed by six semispecies. despite this taxonomic and evolutionary complexity, many of these semi and subspecific tax ...	2010	20049511
hidden cytoplasmic incompatibility alters the dynamics of male-killer/host interactions.	wolbachia manipulate the reproduction of their arthropod hosts in a variety of ways. recent work has demonstrated that these bacteria may combine phenotypes - possessing a 'male killing' phenotype and, where males survive, induce cytoplasmic incompatibility (ci). we here develop a mathematical model to investigate the extent to which 'hidden' ci may affect the evolutionary dynamics of host genes that suppress male-killing activity. we observed that for high prevalence infections, ci drives both ...	2010	20040002
wolbachia: more than just a bug in insects genitals.	research on the intracellular bacterial symbiont wolbachia has grown on many levels, providing interesting insights on various aspects of the microbe's biology. although data from fully sequenced genomes of different wolbachia strains and from experimental studies of host-microbe interactions continue to arise, most of the molecular mechanisms employed by wolbachia to manipulate the host cytoplasmic machinery and to ensure vertical transmission are yet to be discovered. apart from the well-estab ...	2010	20036185
brugia malayi: in vitro effects of ivermectin and moxidectin on adults and microfilariae.	the effect of ivermectin and moxidectin on the motility of brugia malayi adults and microfilariae and on the fertility of b. malayi females was examined. motility was reduced in adults after exposure to both drugs and worms were non-motile and dead within eight days. the motility of microfilariae was significantly reduced at all drug concentrations and ceased at concentrations of 2500 and 5000mug/ml. the motility of microfilariae released by females was reduced after exposure to both drugs, howe ...	2010	20034492
transinfection of wolbachia in planthoppers: nymphal injection of cultured wolbachia and infection dynamics.	wolbachia species are intracellular symbionts that cause reproductive alterations in arthropods. transinfection experiments have been performed in many arthropod species to elucidate the interaction between wolbachia and a new host. to ease transinfection of this bacterium to new arthropod hosts, we introduced two techniques: nymphal injection instead of embryonic injection and the use of a cultured source of wolbachia instead of direct transfer from donors to recipients. wolbachia in the small ...	2009	20021758
human probing behavior of aedes aegypti when infected with a life-shortening strain of wolbachia.	mosquitoes are vectors of many serious pathogens in tropical and sub-tropical countries. current control strategies almost entirely rely upon insecticides, which increasingly face the problems of high cost, increasing mosquito resistance and negative effects on non-target organisms. alternative strategies include the proposed use of inherited life-shortening agents, such as the wolbachia bacterium. by shortening mosquito vector lifespan, wolbachia could potentially reduce the vectorial capacity ...	2009	20016848
phylogenetically distinct wolbachia gene and pseudogene sequences obtained from the african onchocerciasis vector simulium squamosum.	wolbachia are intracellular bacteria mostly found in a diverse range of arthropods and filarial nematodes. they have been classified into seven distinct 'supergroups' and other lineages on the basis of molecular phylogenetics. the arthropod-infecting wolbachia are usually regarded as reproductive parasites because they manipulate their host species' sexing system to enhance their own spread, and this has led to their investigation as potential agents of genetic control in medical entomology. we ...	2010	20005876
association between wolbachia and spiroplasma within drosophila neotestacea: an emerging symbiotic mutualism?	interspecific mutualism can evolve when specific lineages of different species tend to be associated with each other from one generation to the next. different maternally transmitted endosymbionts occurring within the same cytoplasmic lineage fulfil this requirement. drosophila neotestacea is infected with maternally transmitted wolbachia and spiroplasma, which are cotransmitted at high frequency in natural populations. molecular phylogenetic evidence indicates that both endosymbionts have been ...	2010	20002580
characterizing the aedes aegypti population in a vietnamese village in preparation for a wolbachia-based mosquito control strategy to eliminate dengue.	a life-shortening strain of the obligate intracellular bacteria wolbachia, called wmelpop, is seen as a promising new tool for the control of aedes aegypti. however, developing a vector control strategy based on the release of mosquitoes transinfected with wmelpop requires detailed knowledge of the demographics of the target population.	2009	19956588
serum antibody responses to wolbachia surface protein in patients with human lymphatic filariasis.	wolbachia surface protein (wsp), which is the most abundantly expressed protein of wolbachia from the human filarial parasite brugia malayi, was chosen for the present study. b-cell epitope prediction of the wsp protein sequence indicates a high antigenicity, surface probability and hydrophilicity by dna star software analysis. propred analysis suggests the presence of hla class ii binding regions in the wsp protein that contribute to t-cell responses and isotype reactivity. in order to validate ...	2009	19954456
transinfection and growth discrepancy of drosophila wolbachia strain wmel in cell lines of the mosquito aedes albopictus.	the wolbachia strain wmel can protect drosophila melanogaster against pathogenic rna viruses. to analyse the potential of this inhibitory effect against arboviruses vectorized by these mosquitoes, we here first transinfected the aedes albopictus aa23 and c6/36 cell lines with the wolbachia strain wmel and then monitored their infection dynamics.	2010	19951376
computational prediction of essential genes in an unculturable endosymbiotic bacterium, wolbachia of brugia malayi.	wolbachia (wbm) is an obligate endosymbiotic bacterium of brugia malayi, a parasitic filarial nematode of humans and one of the causative agents of lymphatic filariasis. there is a pressing need for new drugs against filarial parasites, such as b. malayi. as wbm is required for b. malayi development and fertility, targeting wbm is a promising approach. however, the lifecycle of neither b. malayi nor wbm can be maintained in vitro. to facilitate selection of potential drug targets we computationa ...	2009	19943957
symmetric and asymmetric mitotic segregation patterns influence wolbachia distribution in host somatic tissue.	wolbachia are maternally inherited bacterial endosymbionts that occupy many but not all tissues of adult insects. during the initial mitotic divisions in drosophila embryogenesis, wolbachia exhibit a symmetric pattern of segregation. wolbachia undergo microtubule-dependent and cell-cycle-regulated movement between centrosomes. symmetric segregation occurs during late anaphase when wolbachia cluster around duplicated and separating centrosomes. this centrosome association is microtubule-dependent ...	2009	19934219
identification and phylogenetic analysis of dirofilaria ursi (nematoda: filarioidea) from wisconsin black bears (ursus americanus) and its wolbachia endosymbiont.	dirofilaria ursi is a filarial nematode of american black bears (ursus americanus pallas, 1780) that is vectored by black flies (simuliidae) in many parts of the united states. in northwestern wisconsin, the prevalence of microfilaremic bears during the fall hunting season was 21% (n = 47). unsheathed blood microfilariae from wisconsin bears possess characters consistent with the original description of d. ursi, as do adult worms observed histologically and grossly. immunohistochemistry was used ...	2010	19916630
rapid spread of male-killing wolbachia in the butterfly hypolimnas bolina.	reproductive parasites such as wolbachia can spread through uninfected host populations by increasing the relative fitness of the infected maternal lineage. however, empirical estimates of how fast this process occurs are limited. here we use nucleotide sequences of male-killing wolbachia bacteria and co-inherited mitochondria to address this issue in the island butterfly hypolimnas bolina. we show that infected specimens scattered throughout the species range harbour the same wolbachia and mito ...	2010	19912450
variation in antiviral protection mediated by different wolbachia strains in drosophila simulans.	drosophila c virus (dcv) is a natural pathogen of drosophila and a useful model for studying antiviral defences. the drosophila host is also commonly infected with the widespread endosymbiotic bacteria wolbachia pipientis. when dcv coinfects wolbachia-infected d. melanogaster, virus particles accumulate more slowly and virus induced mortality is substantially delayed. considering that wolbachia is estimated to infect up to two-thirds of all insect species, the observed protective effects of wolb ...	2009	19911047
lateral phage transfer in obligate intracellular bacteria (wolbachia): verification from natural populations.	lateral transfer of mobile dna is a hallmark of bacteria with a free-living replicative stage; however, its significance in obligate intracellular bacteria and other heritable endosymbionts remains controversial. comparative sequence analyses from laboratory stocks infected with wolbachia pipientis provide some of the most compelling evidence that bacteriophage wo-b transfers laterally between infections of the same insect host. lateral transfer between coinfections, however, has been evaluated ...	2010	19906794
[population genetic analysis of drosophila melanogaster longevity: similar effects of endosymbiont wolbachia and tumor suppressor lgl under conditions of temperature stress].	before, it has been shown that keeping of drosophila wild populations under temperature stress leads to prevalence of deletion alleles of tumor suppressor lgl, and higher survival of heterozygous lgl(-)/+ females descendants (haploadaptivity). on the other hand, recent investigations have demonstrated that an additional dose of lgl gene in transgenic males has inadaptive effect--cytoplasmic incompatibility, caused by the gene, is similar to the effect caused by the widespread endosymbiont wolbac ...	2009	19891414
wolbachia interferes with ferritin expression and iron metabolism in insects.	wolbachia is an intracellular bacterium generally described as being a facultative reproductive parasite. however, wolbachia is necessary for oogenesis completion in the wasp asobara tabida. this dependence has evolved recently as a result of interference with apoptosis during oogenesis. through comparative transcriptomics between symbiotic and aposymbiotic individuals, we observed a differential expression of ferritin, which forms a complex involved in iron storage. iron is an essential element ...	2009	19851452
influence of continuous high temperature conditions on wolbachia infection frequency and the fitness of liposcelis tricolor (psocoptera: liposcelididae).	endosymbiotic bacteria that potentially influence reproduction and other fitness-related traits of their hosts are widespread in arthropods, and their appeal to researchers' interest is growing. in this study, the influence of continuous high temperature conditions on wolbachia infection frequency and the fitness of liposcelis tricolor (psocoptera: liposcelididae) was studied in a laboratory. the results showed that the wolbachia infection frequency was gradually decreased when l. tricolor was r ...	2009	19825290
filariasis and lymphoedema.	among the causes of lymphoedema (le), secondary le due to filariasis is the most prevalent. it affects only a minority of the 120 million people infected with the causative organisms of lymphatic filariasis (lf), wuchereria bancrofti and brugia malayi/timori, but is clustered in families, indicating a genetic basis for development of this pathology. the majority of infected individuals develop filarial-specific immunosuppression that starts even before birth in cases where mothers are infected a ...	2009	19825106
pathogenicity of life-shortening wolbachia in aedes albopictus after transfer from drosophila melanogaster.	maternally inherited wolbachia bacteria have evolved mechanisms to manipulate the reproduction of their invertebrate hosts, promoting infection spread. a high fitness cost to the host is maladaptive for obligate endosymbionts, and prior studies show rapid selection of new wolbachia associations toward commensal or mutualistic symbioses. here, wmelpop wolbachia is transferred from drosophila melanogaster into the mosquito aedes albopictus. characterization of the resulting strain provides an extr ...	2009	19820149
macrofilaricidal activity and amelioration of lymphatic pathology in bancroftian filariasis after 3 weeks of doxycycline followed by single-dose diethylcarbamazine.	in a placebo controlled trial, the effects of 21- and 10-day doxycycline treatments (200 mg/day) followed by single dose diethylcarbamazine (administered 4 months post treatment) on depletion of wolbachia endobacteria from wuchereria bancrofti, filaricidal activity, and amerlioration of scrotal lymph vessel dilation were studied in 57 men from orissa, india. the 21-day doxycycline course reduced wolbachia in w. bancrofti by 94% before diethylcarbamazine administration. after 12 months, all patie ...	2009	19815891
population dynamics and rapid spread of cardinium, a bacterial endosymbiont causing cytoplasmic incompatibility in encarsia pergandiella (hymenoptera: aphelinidae).	cytoplasmic incompatibility (ci) is a common phenotype of maternally inherited bacterial symbionts of arthropods; in its simplest expression, uninfected females produce few or no viable progeny when mated to infected males. infected females thus experience a reproductive advantage relative to that of uninfected females, with the potential for the symbiont to spread rapidly. ci population dynamics are predicted to depend primarily on the strength of incompatibility, the fitness cost of the infect ...	2010	19812617
mansonella perstans--the importance of an endosymbiont.		2009	19812409
a randomized trial of doxycycline for mansonella perstans infection.	mansonella perstans infection is common in areas of africa where wuchereria bancrofti, a causative agent of lymphatic filariasis, is endemic. m. perstans is refractory to standard antifilarial therapies. the recent discovery of bacterial endosymbionts (e.g., wolbachia) in most filarial species, including m. perstans, provides new therapeutic options for reducing microfilaremia.	2009	19812401
brugia malayi gene expression in response to the targeting of the wolbachia endosymbiont by tetracycline treatment.	brugia malayi, like most human filarial parasite species, harbors an endosymbiotic bacterium of the genus wolbachia. elimination of the endosymbiont leads to sterilization of the adult female. previous biochemical and genetic studies have established that communication with its endobacterium is essential for survival of the worm.	2009	19806204
first isolation of enterobacter, enterococcus, and acinetobacter spp. as inhabitants of the tsetse fly (glossina palpalis palpalis) midgut.	this paper reports the first evidence of the presence of bacteria, other than the three previously described as symbionts, wigglesworthia glossinidia, wolbachia, and sodalis glossinidius, in the midgut of glossina palpalis palpalis, the tsetse fly, a vector of the chronic form of human african trypanosomiasis in sub-saharan african countries. based on the morphological, nutritional, physiological, and phylogenetic results, we identified enterobacter, enterococcus, and acinetobacter spp. as inhab ...	2009	19800031
immune activation by life-shortening wolbachia and reduced filarial competence in mosquitoes.	wolbachia strain wmelpop reduces the longevity of its drosophila melanogaster host and, when introduced into the mosquito aedes aegypti, halves its life span. we show that wmelpop induces up-regulation of the mosquito's innate immune system and that its presence inhibits the development of filarial nematodes in the mosquito. these data suggest that wmelpop could be used in the global effort to eliminate lymphatic filariasis and possibly for the control of other mosquito-borne parasites where imm ...	2009	19797660
drosophila-parasitoid communities as model systems for host-wolbachia interactions.	wolbachia bacteria are cytoplasmic endosymbionts that infect a wide range of arthropod and nematode hosts. they are transmitted from mother to offspring via the eggs (vertical transmission) and enhance their transmission to the next generation by manipulating the reproductive system of their hosts. these manipulations occur in many forms, such as the induction of cytoplasmic incompatibility, feminization, male killing and parthenogenesis induction. wolbachia is estimated to occur in up to 66% of ...	2009	19773076
characterization and evolution of two bacteriome-inhabiting symbionts in cixiid planthoppers (hemiptera: fulgoromorpha: pentastirini).	like other plant sap-sucking insects, planthoppers within the family cixiidae (insecta: hemiptera: fulgoromorpha) host a diversified microbiota. we report the identification and first molecular characterization of symbiotic bacteria in cixiid planthoppers (tribe: pentastirini). using universal eubacterial primers we first screened the eubacterial 16s rrna sequences in pentastiridius leporinus (linnaeus) with pcr amplification, cloning, and restriction fragment analysis. we identified three main ...	2009	19758348
newly acquired onchocerca volvulus filariae after doxycycline treatment.	despite successful mass drug administration and vector control programs, the nematode onchocerca volvulus is far from being eradicated. therefore, new long-term sterilizing or macrofilaricidal drugs are needed. the depletion of wolbachia endobacteria using doxycycline leads to long-term sterilizing effects and macrofilaricidal activity against female filariae of more than 60%. the worms die or degenerate 18-27 months after doxycycline. however, during this time patients may be exposed to new inf ...	2009	19756742
wolbachia infection reduces blood-feeding success in the dengue fever mosquito, aedes aegypti.	the mosquito aedes aegypti was recently transinfected with a life-shortening strain of the endosymbiont wolbachia pipientis (wmelpop) as the first step in developing a biocontrol strategy for dengue virus transmission. in addition to life-shortening, the wmelpop-infected mosquitoes also exhibit increased daytime activity and metabolic rates. here we sought to quantify the blood-feeding behaviour of wolbachia-infected females as an indicator of any virulence or energetic drain associated with wol ...	2009	19753103
rapidly shifting sex ratio across a species range.	sex ratios are subject to distortion by a range of inherited parasites. although it has been predicted that the presence of these elements will result in spatial and temporal variation in host sex ratio, testing of this hypothesis has been constrained by availability of historical data. we here determine spatial and temporal variation in sex ratio in a interaction between a butterfly and male-killing wolbachia bacteria by assaying infection presence in museum specimens, and from this inferring i ...	2009	19747825
distribution of wolbachia infection in chorthippus parallelus populations within and beyond a pyrenean hybrid zone.	two subspecies of the meadow grasshopper chorthippus parallelus meet in a secondary hybrid zone in the pyrenees. we have recently detected wolbachia infection in this extensively studied species. c. p. parallelus (cpp) and c. p. erythropus (cpe) harbour bacteria from the b and f supergroups, but they differ noticeably in the incidence and type of infection present in their populations. we can distinguish different regional infection patterns that are associated with the distribution of pure and ...	2010	19738635
prevalence of cardinium bacteria in planthoppers and spider mites and taxonomic revision of "candidatus cardinium hertigii" based on detection of a new cardinium group from biting midges.	cardinium bacteria, members of the phylum cytophaga-flavobacterium-bacteroides (cfb), are intracellular bacteria in arthropods that are capable of inducing reproductive abnormalities in their hosts, which include parasitic wasps, mites, and spiders. a high frequency of cardinium infection was detected in planthoppers (27 out of 57 species were infected). a high frequency of cardinium infection was also found in spider mites (9 out of 22 species were infected). frequencies of double infection by ...	2009	19734338
hidden wolbachia diversity in field populations of the european cherry fruit fly, rhagoletis cerasi (diptera, tephritidae).	the european cherry fruit fly rhagoletis cerasi has been a field model for cytoplasmic incompatibility since the mid 1970s. two wolbachia strains were detected in this tephritid species and wcer2 was described as the ci inducing agent dividing european populations into two unidirectional incompatible groups, i.e. southern females produce viable offspring with northern males, whereas the reciprocal cross results in incompatibility. we detected three new wolbachia strains by sequencing a multitude ...	2009	19732336
effect of intracellular wolbachia on interspecific crosses between drosophila melanogaster and drosophila simulans.	wolbachia are bacteria that live inside the cells of a large number of invertebrate hosts and are transmitted from infected females to their offspring. their presence is associated with cytoplasmic incompatibility in several species of drosophila. cytoplasmic incompatibility results when the sperm of infected males fertilize eggs of uninfected females, causing more or less intense embryonic mortality (unidirectional incompatibility). this phenomenon also appears in crosses between populations in ...	2009	19731208
tetracycline treatment targeting wolbachia affects expression of an array of proteins in brugia malayi parasite.	wolbachia is an intracellular endosymbiont of brugia malayi parasite whose presence is essential for the survival of the parasite. treatment of b. malayi-infected jirds with tetracycline eliminates wolbachia, which affects parasite survival and fitness. in the present study we have tried to identify parasite proteins that are affected when wolbachia is targeted by tetracycline. for this wolbachia depleted parasites (b. malayi) were obtained by tetracycline treatment of infected mongolian jirds ( ...	2009	19722191
what is new about animal and human dirofilariosis?	dirofilaria immitis and d. repens, the causal agents of cardiopulmonary and subcutaneous dirofilariosis, respectively, affect canine, feline and human populations with an increasing incidence in temperate and tropical areas of the world. in the past decade outstanding advances in the knowledge of dirofilariosis have been achieved. nevertheless, questions such as the impact of climate change in the transmission and distribution of dirofilariosis, as well as a profound evaluation of both the role ...	2009	19720566
diversity of bacteria associated with collembola - a cultivation-independent survey based on pcr-amplified 16s rrna genes.	the bacterial communities found in eight different soil-inhabiting microarthropod species of the class collembola (springtails) were analyzed by analysis of pcr-amplified 16s rrna genes obtained without cultivation from total dna. to characterize the bacteria associated with the parthenogenetically-reproducing folsomia candida, the almost complete 16s rrna genes were amplified with three universal primers, i.e., the forward primer f27 and the reverse primer r1492 or r1525. with the reverse prime ...	2004	19712416
reproductive compensation favours male-killing wolbachia in a live-bearing host.	wolbachia are maternally inherited, cellular endosymbionts that can enhance their fitness by biasing host sex ratio in favour of females. male killing (mk) is an extreme form of sex-ratio manipulation that is selectively advantageous if the self-sacrifice of wolbachia in males increases transmission through females. in live-bearing hosts, females typically produce more embryos than can be carried to term, and reproductive compensation through maternal resource reallocation from dead males to fem ...	2009	19710065
unexplained split sex ratios in the neotropical plant-ant, allomerus octoarticulatus var. demerarae (myrmicinae): a test of hypotheses.	we investigated sex allocation in the neotropical ant allomerus octoarticulatus var. demerarae. because allomerus is a plant symbiont, we could make geographically extensive collections of complete colonies and of foundresses in saplings, allowing us to estimate not only population- and colony-level sex allocation but also colony resource levels and the relatedness of competing ant foundresses. this species exhibits a strongly split sex ratio, with 80% of mature colonies producing >or=90% of one ...	2010	19703224
superinfection of five wolbachia in the alnus ambrosia beetle, xylosandrus germanus (blandford) (coleoptera: curuculionidae).	wolbachia bacteria are among the most common endosymbionts in insects. in wolbachia research, the wolbachia surface protein (wsp) gene has been used as a phylogenetic tool, but relationships inferred by single-locus analysis can be unreliable because of the extensive genome recombination among wolbachia strains. therefore, a multilocus sequence typing (mlst) method for wolbachia, which relies upon a set of five conserved genes, is recommended. in this study, we examined whether the alnus ambrosi ...	2010	19698196
antibiotic treatment leads to the elimination of wolbachia endosymbionts and sterility in the diplodiploid collembolan folsomia candida.	wolbachia is an extremely widespread bacterial endosymbiont of arthropods and nematodes that causes a variety of reproductive peculiarities. parthenogenesis is one such peculiarity but it has been hypothesised that this phenomenon may be functionally restricted to organisms that employ haplodiploid sex determination. using two antibiotics, tetracycline and rifampicin, we attempted to eliminate wolbachia from the diplodiploid host folsomia candida, a species of springtail which is a widely used s ...	2009	19698188
the endosymbiont wolbachia increases insulin/igf-like signalling in drosophila.	insulin/igf-like signalling (iis) is an evolutionarily conserved pathway that has diverse functions in multi-cellular organisms. mutations that reduce iis can have pleiotropic effects on growth, development, metabolic homeostasis, fecundity, stress resistance and lifespan. iis is also modified by extrinsic factors. for instance, in the fruitfly drosophila melanogaster, both nutrition and stress can alter the activity of the pathway. here, we test experimentally the hypothesis that a widespread e ...	2009	19692410
longicorn beetle that vectors pinewood nematode carries many wolbachia genes on an autosome.	monochamus alternatus is the longicorn beetle notorious as a vector of the pinewood nematode that causes the pine wilt disease. when two populations of m. alternatus were subjected to diagnostic polymerase chain reaction (pcr) detection of four wolbachia genes, only the ftsz gene was detected from one of the populations. the wolbachia ftsz gene persisted even after larvae were fed with a tetracycline-containing diet for six weeks. the inheritance of the ftsz gene was not maternal but biparental, ...	2009	19692404
effects of crowding and temperature on wolbachia infection density among life cycle stages of aedes albopictus.	species of the genus wolbachia are a group of rickettsia-like, maternally-inherited bacteria (gram negative), which cause various reproductive alterations in their arthropod and nematode hosts including cytoplasmic incompatibility (ci), male-killing, parthenogenesis and feminization. they can be divided into supergroups such as a and b based on phylogenetic analysis of 16s rdna sequences. in this study, we examined the relative infection densities of wolbachia strains among life cycle stages in ...	2009	19686755
cytoplasmic incompatibility in populations with overlapping generations.	many insects and other arthropods harbor maternally inherited bacteria inducing "cytoplasmic incompatibility" (ci), reduced egg hatch when infected males mate with uninfected females. ci-causing infections produce a frequency-dependent reproductive advantage for infected females. however, many such infections impose fitness costs that lead to unstable equilibrium frequencies below which the infections tend to be eliminated. to understand the unstable equilibria produced by reduced lifespan or le ...	2010	19686264
integration of irradiation with cytoplasmic incompatibility to facilitate a lymphatic filariasis vector elimination approach.	abstract:	2009	19682363
huge symbiotic organs in giant scale insects of the genus drosicha (coccoidea: monophlebidae) harbor flavobacterial and enterobacterial endosymbionts.	giant scale insects (drosicha: coccoldea: monophlebidae) were investigated for their symbiotic organs and bacterial endosymbionts. two types of bacterial 16s rrna gene sequences, flavobacterial and enterobacterial, were consistently detected in d. corpulenta and d. pinicola. the former sequences formed a compact clade in the bacteroidetes, allied to the symbionts of cushion and armored scales. the latter sequences formed a robust clade in the gamma-proteobacteria, allied to enteric bacteria like ...	2009	19663639
effects of parthenogenesis and geographic isolation on female sexual traits in a parasitoid wasp.	population divergence in sexual traits is affected by different selection pressures, depending on the mode of reproduction. in allopatric sexual populations, aspects of sexual behavior may diverge due to sexual selection. in parthenogenetic populations, loss-of-function mutations in genes involved in sexual functionality may be selectively neutral or favored by selection. we assess to what extent these processes have contributed to divergence in female sexual traits in the parasitoid wasp leptop ...	2009	19659591
functional conservation of the lipid ii biosynthesis pathway in the cell wall-less bacteria chlamydia and wolbachia: why is lipid ii needed?	cell division and cell wall biosynthesis in prokaryotes are driven by partially overlapping multiprotein machineries whose activities are tightly controlled and co-ordinated. so far, a number of protein components have been identified and acknowledged as essential for both fundamental cellular processes. genes for enzymes of both machineries have been found in the genomes of the cell wall-less genera chlamydia and wolbachia, raising questions as to the functionality of the lipid ii biosynthesis ...	2009	19656295
rapid evolution of wolbachia density in insecticide resistant culex pipiens.	the maternally inherited symbiotic wolbachia have been previously shown to have much greater densities in insecticide-resistant culex pipiens mosquitoes than in insecticide-susceptible individuals. these high densities were shown to be at least partially responsible for the costs related to insecticide resistance in this species. we report here the rapid evolution, on the order of 50 generations, of bacterial densities both in laboratory and field populations. along with other recently published ...	2010	19654607
maintenance of adaptive differentiation by wolbachia induced bidirectional cytoplasmic incompatibility: the importance of sib-mating and genetic systems.	bacteria of the genus wolbachia are reproductive parasites widespread among arthropods. the most common effect arising from the presence of wolbachia in a population is cytoplasmic incompatibility (ci), whereby postmating reproductive isolation occurs in crosses between an infected male and an uninfected female, or when a male is infected with a different strain of wolbachia to that of the female (bidirectional ci). previous theoretical models have demonstrated that bidirectional ci can contribu ...	2009	19653892
pcr analysis for wolbachia in human and canine demodex mites.	in many skin diseases such as demodex folliculitis, rosacea- or steroid-induced rosacea demodex mites are present in abundance and are at least partially held responsible for causing these disorders. although it is known that these diseases respond well to tetracyclines, it is unclear if this is due to the antiinflammatory effects of the antibiotics or to an antibacterial effect on so far unknown bacteria within the demodex mites. as in filariasis, where the response to doxycycline can be explai ...	2009	19652990
variation in sex peptide expression in d. melanogaster.	male drosophila melanogaster transfers many accessory-gland proteins to females during copulation. sex peptide (sp) is one of these and one of its main effects is to decrease female remating propensity. to date, there has been no investigation of genetic variation in sp-gene expression levels, or if such potential variation directly influences female remating behaviour. we assessed both these possibilities and found significant variation in expression levels of the sp gene across d. melanogaster ...	2009	19640319
persistent wolbachia and cultivable bacteria infection in the reproductive and somatic tissues of the mosquito vector aedes albopictus.	commensal and symbiotic microbes have a considerable impact on the behavior of many arthropod hosts, including hematophagous species that transmit pathogens causing infectious diseases to human and animals. little is known about the bacteria associated with mosquitoes other than the vectorized pathogens. this study investigated wolbachia and cultivable bacteria that persist through generations in ae. albopictus organs known to host transmitted arboviruses, such as dengue and chikungunya.	2009	19633721
[paradigm shift in bancroftian filariasis].	the way a particular subject is understood changes over time as a result of scientific research. in most cases, these changes are minor, with limited effect on the overall knowledge on the subject. sometimes, however, revolutionary changes occur and not only modify the understanding of the subject but open perspectives that can trigger new interpretations and new ways for expansion of scientific knowledge. the studies of gregor johann mendel were a good example. they led to discovery of the laws ...	2009	19629359
discover the microbes within! the hhmi wolbachia project.		2009	19603576
the heme biosynthetic pathway of the obligate wolbachia endosymbiont of brugia malayi as a potential anti-filarial drug target.	filarial parasites (e.g., brugia malayi, onchocerca volvulus, and wuchereria bancrofti) are causative agents of lymphatic filariasis and onchocerciasis, which are among the most disabling of neglected tropical diseases. there is an urgent need to develop macro-filaricidal drugs, as current anti-filarial chemotherapy (e.g., diethylcarbamazine [dec], ivermectin and albendazole) can interrupt transmission predominantly by killing microfilariae (mf) larvae, but is less effective on adult worms, whic ...	2009	19597542
molecular phylogeography of culex quinquefasciatus mosquitoes in central bangladesh.	mosquitoes in the culex pipiens complex are a major vector of numerous parasitic and arboviral diseases. here we report the phylogeography of a prevalent culex mosquito, cx. quinquefasciatus, from three locations in bangladesh: dhaka, savar and mymensingh. sequence analysis of the genes encoding mitochondrial cytochrome oxidase subunit ii, nuclear elongation factor-1 alpha, and acetylcholinesterase-2 revealed the lack of a population genetic structure among the three locations. moreover, the hig ...	2009	19595661
complete wo phage sequences reveal their dynamic evolutionary trajectories and putative functional elements required for integration into the wolbachia genome.	wolbachia endosymbionts are ubiquitously found in diverse insects including many medical and hygienic pests, causing a variety of reproductive phenotypes, such as cytoplasmic incompatibility, and thereby efficiently spreading in host insect populations. recently, wolbachia-mediated approaches to pest control and management have been proposed, but the application of these approaches has been hindered by the lack of genetic transformation techniques for symbiotic bacteria. here, we report the geno ...	2009	19592535
microbial modification of host long-distance dispersal capacity.	dispersal plays a key role in shaping biological and ecological processes such as the distribution of spatially-structured populations or the pace and scale of invasion. here we have studied the relationship between long-distance dispersal behaviour of a pest-controlling money spider, erigone atra, and the distribution of maternally acquired endosymbionts within the wider meta-population. this spider persists in heterogeneous environments because of its ability to recolonise areas through active ...	2009	19545353
molecular systematics of filarial parasites, with an emphasis on groups of medical and veterinary importance, and its relevance for epidemiology.	filarial parasites are members of the phylum nemata that comprise several species of medical and veterinary importance. among the human diseases caused by members of this group of nematodes are river blindness and lymphatic filariasis, which afflict millions of people in the tropics. these diseases not only have an impact on the health of the people affected but also bear a great socioeconomic burden. despite their relevance, the systematics of the filarial parasites is not well understood yet, ...	2009	19539785
infection by wolbachia bacteria and its influence on the reproduction of the stored-product psocid, liposcelis tricolor.	wolbachia are maternally inherited intracellular bacteria that infect a wide range of arthropods and nematodes and are associated with various reproductive abnormalities in their hosts. the infection by wolbachia of the psocid, liposcelis tricolor (psocoptera: liposcelididae), was investigated using long pcr amplification of the wsp gene that codes for a wolbachia surface protein. the results showed that l. tricolor was positive for wolbachia . phylogenetic analysis showed that the wolbachia fou ...	2006	19537991
wolbachia in anastrepha fruit flies (diptera: tephritidae).	endosymbiotic bacteria of the genus wolbachia are widespread among arthropods and cause a variety of reproductive abnormalities, such as cytoplasmic incompatibility, thelytokous parthenogenesis, male-killing, and host feminization. in this study, we used three sets of wolbachia-specific primers (16s rdna, ftsz, and wsp) in conjunction with the polymerase chain reaction (pcr), cloning and sequencing to study the infection of fruit flies (anastrepha spp. and ceratitis capitata) by wolbachia. the f ...	2009	19536597
the differential interaction of brucella and ochrobactrum with innate immunity reveals traits related to the evolution of stealthy pathogens.	during evolution, innate immunity has been tuned to recognize pathogen-associated molecular patterns. however, some alpha-proteobacteria are stealthy intracellular pathogens not readily detected by this system. brucella members follow this strategy and are highly virulent, but other brucellaceae like ochrobactrum are rhizosphere inhabitants and only opportunistic pathogens. to gain insight into the emergence of the stealthy strategy, we compared these two phylogenetically close but biologically ...	2009	19529776
wolbachia induces strong cytoplasmic incompatibility in the predatory bug macrolophus pygmaeus.	macrolophus pygmaeus is a heteropteran predator that is widely used in european glasshouses for the biological control of whiteflies, aphids, thrips and spider mites. we have demonstrated that the insect is infected with the endosymbiotic bacterium wolbachia pipientis. several gene fragments of the endosymbiont were sequenced and subsequently used for phylogenetic analysis, revealing that it belongs to the wolbachia supergroup b. the endosymbiont was visualized within the ovarioles using immunol ...	2009	19523069
the effect of sibmating on the infection dynamics of male-killing bacteria.	male-killing (mk) bacteria are vertically transmitted endosymbionts that selectively kill the male offspring of their hosts. simple mathematical models describe the infection dynamics using two parameters, the bacterial transmission rate and a fitness compensation for siblings of killed males. these models cannot explain two phenomena that have been observed in nature: the persistence of extreme mk causing all-female broods, and the coexistence of two different strains of mk bacteria in the same ...	2009	19519634
a new case of wolbachia dependence in the genus asobara: evidence for parthenogenesis induction in asobara japonica.	wolbachia is a maternally inherited bacterium that is widely distributed among arthropods, in which it manipulates the reproduction of its hosts. although generally facultative for its hosts, wolbachia has recently become obligatory in asobara tabida (hymenoptera: braconidae) in which it is required for the completion of oogenesis. here, we describe a new wolbachia strain (wajap) that is associated with the genus asobara and infects asobara japonica. wajap was detected in all female-biased popul ...	2009	19513092
essential but unhelpful wasp wolbachia.		2009	19513090
[influence of drosophila melanogaster genotype on biological effects of endocymbiont wolbachia (stamm wmelpop)].	comparative analyses of symbiotic bacteria wolbachia (stamm wmelpop reducing lifespan of flies) morphology in normal and mutant strains of drosophila melanogaster as well as the influence of wolbachia on the host cell ultrastructure have been done. wolbachia infected d. melanogaster mutation strains trithorax-like -- trl362/tm3, sb1 ser y+ and trlen82/tm3, sb1 ser y+ have been received by special flies crossing. uninfected strain d. melanogaster white-1118 (w1118) have been obtained by antibioti ...	2009	19505052
an endosymbiotic bacterium in a plant-parasitic nematode: member of a new wolbachia supergroup.	wolbachia is an endosymbiotic bacterium widely present in arthropods and animal-parasitic nematodes. despite previous efforts, it has never been identified in plant-parasitic nematodes. random sequencing of genes expressed by the burrowing nematode radopholus similis resulted in several sequences with similarity to wolbachia genes. the presence of a wolbachia-like endosymbiont in this plant-parasitic nematode was investigated using both morphological and molecular approaches. transmission electr ...	2009	19504759
the popcorn wolbachia infection of drosophila melanogaster: can selection alter wolbachia longevity effects?	wolbachia popcorn (wmelpop), a life-shortening strain of wolbachia, has been proposed as an agent for suppressing transmission of dengue fever following infection of the vectoring mosquito aedes aegypti. however, evolutionary changes in the host and wolbachia genomes might attenuate any life span effects mediated by wmelpop. here we test for attenuation by selecting strains of drosophila melanogaster infected with wmelpop for early and late reproduction in three independent outcrossed population ...	2009	19500146
wolbachia infection and resource competition effects on immature aedes albopictus (diptera: culicidae).	wolbachia pipientis hertig and wolbach (rickettsiales: rickettsiaceae) are intracellular alpha-proteobacteria that occur naturally in aedes albopictus (skuse) (diptera: culicidae) and numerous other invertebrates. these endosymbionts can invade host populations by manipulating host reproduction. wolbachia infections have been shown to impart both costs and benefits to hosts in terms of development, survival, and fecundity. here, we monitor intraspecific competition among independent cohorts of i ...	2009	19496412
variable incidence of spiroplasma infections in natural populations of drosophila species.	spiroplasma is widespread as a heritable bacterial symbiont in insects and some other invertebrates, in which it sometimes acts as a male-killer and causes female-biased sex ratios in hosts. besides wolbachia, it is the only heritable bacterium known from drosophila, having been found in 16 of over 200 drosophila species screened, based on samples of one or few individuals per species. to assess the extent to which spiroplasma infection varies within and among species of drosophila, intensive sa ...	2009	19492088
the effect of gene drive on containment of transgenic mosquitoes.	mosquito-borne diseases such as malaria and dengue fever continue to be a major health problem through much of the world. several new potential approaches to disease control utilize gene drive to spread anti-pathogen genes into the mosquito population. prior to a release, these projects will require trials in outdoor cages from which transgenic mosquitoes may escape, albeit in small numbers. most genes introduced in small numbers are very likely to be lost from the environment; however, gene dri ...	2009	19490857
further evidence for the absence of bacteria in horsehair worms (nematomorpha: gordiidae).	we used molecular techniques to characterize bacteria associated with the nematomorph gordius robustus (leidy). this worm is a parasite of the fall field cricket, gryllus pennsylvanicus (burmeister), which is infected with the symbiotic bacteria, wolbachia. because of this close association, our a priori expectation was that g. robustus may be similarly infected. however, results of denaturing gradient gel electrophoresis and sequencing of amplified 16s rdna failed to detect any bacteria (symbio ...	2009	19489671
conservation of the type iv secretion system throughout wolbachia evolution.	the type iv secretion system (t4ss) is an efficient pathway with which bacteria can mediate the transfer of dna and/or proteins to eukaryotic cells. in wolbachia pipientis, a maternally inherited obligate endosymbiont of arthropods and nematodes, two operons of vir genes, virb3-b6 and virb8-d4, encoding a t4ss were previously identified and characterized at two separate genomic loci. using the largest data set of wolbachia strains studied so far, we show that vir gene sequence and organization a ...	2009	19486895
current practices in the management of lymphatic filariasis.	lymphatic filariasis is a major cause of acute and chronic morbidity in 81 countries. the availability of safe treatment regimens along with rapid diagnostic tools resulted in a global program to eliminate the disease. the two main objectives of the global elimination program are to interrupt transmission of the parasites and to provide care for those with the disease. the strategy for transmission interruption is preventive chemotherapy through mass drug administration. this article reviews the ...	2009	19485799
susceptibility to insecticides in the q biotype of bemisia tabaci is correlated with bacterial symbiont densities.	the presence of symbiotic microorganisms may influence an insect's ability to tolerate natural and artificial stress agents such as insecticides. the authors have previously shown that rickettsia in the b biotype of the whitefly bemisia tabaci (gennadius) (homoptera: aleyrodidae) increases this insect's susceptibility to several insecticidal compounds. this communication reports a comparison of the susceptibilities of three isofemale strains of the q biotype of b. tabaci harbouring different bac ...	2009	19479746
reduction in levels of plasma vascular endothelial growth factor-a and improvement in hydrocele patients by targeting endosymbiotic wolbachia sp. in wuchereria bancrofti with doxycycline.	the treatment for hydrocele is expensive, invasive surgery-hydrocelectomy. a drug that could prevent or improve this condition could replace or supplement hydrocelectomy. in ghana, 42 hydrocele patients participated in a double-blind, placebo-controlled trial of a six-week regimen of doxycycline, 200 mg/day. four months after doxycycline treatment, patients received 150 mug/kg of ivermectin and 400 mg of albendazole, which is used for mass chemotherapy in this area. patients were monitored for l ...	2009	19478258
wolbachia lipoprotein stimulates innate and adaptive immunity through toll-like receptors 2 and 6 to induce disease manifestations of filariasis.	wolbachia endosymbiotic bacteria have been implicated in the inflammatory pathogenesis of filariasis. inflammation induced by brugia malayi female worm extract (bmfe) is dependent on toll-like receptors 2 and 6 (tlr2/6) with only a partial requirement for tlr1. removal of wolbachia, lipids, or proteins eliminates all inflammatory activity. wolbachia bacteria contain the lipoprotein biosynthesis genes ltg and lspa but not lnt, suggesting wolbachia proteins cannot be triacylated, accounting for re ...	2009	19458089
the nematode parasite onchocerca volvulus generates the transforming growth factor-beta (tgf-beta).	transforming growth factor-beta (tgf-beta) is a highly conserved cytokine that has a well-known regulatory role in immunity, but also in organ development of most animal species including helminths. homologous tgf-b genes and mrna have been detected in the filaria brugia malayi. the in situ protein expression is unknown for filariae. therefore, we examined several filariae for the expression and localization of latent (stable) tgf-beta in adult and larval stages. a specific goat anti-human laten ...	2009	19452170
identification of immunoreactive proteins from the dog heartworm (dirofilaria immitis) differentially recognized by the sera from dogs with patent or occult infections.	heartworm disease caused by dirofilaria immitis affects canine and feline hosts. moreover, the parasite can infect humans, causing pulmonary dirofilariosis. most affected dogs have patent infections with circulating microfilariae in peripheral blood, although infected dogs sometimes develop occult infections characterized by the absence of microfilariae. microfilaremic infections (mf+) are associated with a predominant th2-type immune response, whereas a th1-type response predominates in amicrof ...	2009	19450730
cytoplasmic incompatibility and host population structure.	many arthropod species are infected by maternally inherited bacteria that induce cytoplasmic incompatibility (ci). ci causes embryonic mortality in offspring when infected males mate with either uninfected females or with females that are infected with a different strain of bacteria. here, we review theoretical and empirical studies concerning the infection dynamics of ci-inducing bacteria, focusing in particular on the impact of the host population structure on the spread of ci. as different th ...	2009	19436325
improved efficacy of tetracycline by acaciasides on dirofilaria immitis.	the discovery of wolbachia, a bacterial endosymbiont that occurs in the filarial parasite and its sensitivity to tetracycline, has fostered a new initiative in the development of suitable antifilarial drugs. the present study is an attempt to investigate whether adding acaciasides (saponins from acacia auriculiformis) to the standard dose of tetracycline would further improve the efficacy of tetracycline treatment against dirofilaria immitis microfilariae in vivo. treatment of microfilaremic adu ...	2009	19430817
wolbachia as populations within individual insects: causes and consequences of density variation in natural populations.	the population-level dynamics of maternally transmitted endosymbionts, including reproductive parasites, depends primarily on the fitness effects and transmission fidelity of these infections. although experimental laboratory studies have shown that within-host endosymbiont density can affect both of these factors, the existence of such effects in natural populations has not yet been documented. using quantitative pcr, we survey the density of male-killing wolbachia in natural populations of dro ...	2009	19419989
gene conversion maintains nonfunctional transposable elements in an obligate mutualistic endosymbiont.	long-term bacterial endosymbionts typically exhibit reduced genomes, lack genes encoding recombination functions and transposable elements, such as insertion sequences (iss). in sharp contrast, i found that iss constitute 2.4% of the genome of the obligate mutualistic endosymbiont wolbachia wbm. although no is copy is transpositionally functional, i show that iss persist in wbm because of frequent recombinational gene conversion (gc) homogenizing homologous is sequences. these results not only i ...	2009	19414524
increased locomotor activity and metabolism of aedes aegypti infected with a life-shortening strain of wolbachia pipientis.	a virulent strain of the obligate intracellular bacterium wolbachia pipientis that shortens insect lifespan has recently been transinfected into the primary mosquito vector of dengue virus, aedes aegypti l. the microbe's ability to shorten lifespan and spread through host populations under the action of cytoplasmic incompatibility means it has the potential to be used as a biocontrol agent to reduce dengue virus transmission. wolbachia is present in many host tissues and may have local effects o ...	2009	19411536
extensive genomic diversity of closely related wolbachia strains.	using microarray-based comparative genome hybridization (mcgh), the genomic content of wolbachia pipientis wmel from drosophila melanogaster was compared to the closely related wolbachia from d. innubila (winn), d. santomea (wsan), and three strains from d. simulans (wau, wri, wsim). a large number of auxiliary genes are identified in these five strains, with most absent/divergent genes being unique to a given strain. each strain caused an average of approximately 60 genes to be removed from the ...	2009	19389774
cytological detection of wolbachia in squashed and paraffin embedded insect tissues.	wolbachia localization in situ is essential for accurate analysis of the infection and its consequences. whole cell hybridization is proposed as an easy and rapid method for detecting wolbachia cells in paraffin embedded tissues or testis squashes of chorthippus parallelus (orthoptera). wolbachia is found in whole gonads and other adjacent tissues. a higher bacterial density, however, is observed in ovarioles and testis. small independent bacteria with strictly cytoplasmic distribution are displ ...	2009	19384745
evidence for low-titre infections in insect symbiosis: wolbachia in the bark beetle pityogenes chalcographus (coleoptera, scolytinae).	wolbachia are obligatory endosymbiotic alpha-proteobacteria found in many insect species. they are maternally transmitted and often exhibit reproductive phenotypes like cytoplasmic incompatibility. pityogenes chalcographus is a bark beetle causing severe damage in spruce stands. its european populations are divided into several mitochondrial clades separated by partial crossing barriers. in this study, we tested a large sample set covering the natural range of the beetle in europe for the presen ...	2009	19383035
wolbachia and bacteriophage wo-b density of wolbachia a-infected aedes albopictus mosquito.	wolbachia are maternally inherited symbiotic bacteria capable of inducing an extensive range of reproductive abnormalities in their hosts, including cytoplasmic incompatibility (ci). its density (concentration) is likely to influence the penetrance of ci in incompatible crosses. the variations of wolbachia density could also be linked with phage wo density. we determined the relative density (relative concentration) of prophage wo orf7 and wolbachia (phage-to-bacteria ratio) during early develop ...	2009	19381483
new insights into the biology of filarial infections.	recent successes in the control of lymphatic filariasis and onchocerciasis need continuing research in order to sustain the achievements and to develop further tools to tackle the new questions that arise when only reduced infection prevalences prevail. in this regard, in a symposium held at the xth european multicolloquium of parasitology (august 2008, paris) questions such as the impact of filarial immunosuppression, and its lack following filarial control, on the outcome of co-infections were ...	2009	19379544
composition of bacterial communities associated with natural and laboratory populations of asobara tabida infected with wolbachia.	asobara tabida wasps are fly endoparasitoids that naturally harbor three wolbachia strains, which induce cytoplasmic incompatibility and control oogenesis. to investigate whether other bacteria play a role in wasp biology, we surveyed the bacterial communities of wild a. tabida populations originating from different regions of france and of laboratory colonies using pcr-denaturing gradient gel electrophoresis and culture methods. proteobacteria and firmicutes were found to be the main phyla repr ...	2009	19376923
no sex in fungus-farming ants or their crops.	asexual reproduction imposes evolutionary handicaps on asexual species, rendering them prone to extinction, because asexual reproduction generates novel genotypes and purges deleterious mutations at lower rates than sexual reproduction. here, we report the first case of complete asexuality in ants, the fungus-growing ant mycocepurus smithii, where queens reproduce asexually but workers are sterile, which is doubly enigmatic because the clonal colonies of m. smithii also depend on clonal fungi fo ...	2009	19369264
unravelling the wolbachia evolutionary role: the reprogramming of the host genomic imprinting.	environmental factors can induce significant epigenetic changes that may also be inherited by future generations. the maternally inherited symbiont of arthropods wolbachia pipientis is an excellent candidate as an 'environmental' factor promoting trans-generational epigenetic changes: by establishing intimate relationships with germ-line cells, epigenetic effects of wolbachia symbiosis would be manifested as a 'maternal effect', in which infection of the mother modulates the offspring phenotype. ...	2009	19364731