Publications

diversity of wolbachia isolated from the cubitermes sp. affinis subarquatus complex of species (termitidae), revealed by multigene phylogenies.	wolbachia are endosymbiotic bacteria that may alter the reproductive mechanisms of arthropod hosts. eusocial termites provide considerable scope for wolbachia studies owing to their ancient origin, their great diversity and their considerable ecological, biological and behavioral plasticity. this article describes the phylogenetic distribution of wolbachia infecting termites of the cubitermes genus, which are particularly abundant soil-feeders in equatorial africa. fourteen colonies of the cubit ...	2007	17663704
male development time influences the strength of wolbachia-induced cytoplasmic incompatibility expression in drosophila melanogaster.	cytoplasmic incompatibility (ci) is the most widespread reproductive modification induced in insects by the maternally inherited intracellular bacteria, wolbachia. expression of ci in drosophila melanogaster is quite variable. published papers typically show that ci expression is weak and often varies between different drosophila lines and different labs reporting the results. the basis for this variability is not well understood but is often considered to be due to unspecified host genotype int ...	2007	17660578
absence of wolbachia in nonfilariid worms parasitizing arthropods.	wolbachia are strictly intracellular maternally inherited alpha-proteobacteria, largely widespread among arthropods and filariids (i.e., filarial nematodes). wolbachia capacities to infect new host species have been greatly evidenced and the transfer of wolbachia between arthropods and filariids has probably occurred more than once. interestingly, among nematode species, wolbachia infection was found in filariids but not in closely related lineages. their occurrence in filariids has been suppose ...	2007	17657540
biotype-dependent secondary symbiont communities in sympatric populations of bemisia tabaci.	the sweet potato whitefly, bemisia tabaci, harbors portiera aleyrodidarum, an obligatory symbiotic bacterium, as well as several secondary symbionts including rickettsia, hamiltonella, wolbachia, arsenophonus, cardinium and fritschea, the function of which is unknown. bemisia tabaci is a species complex composed of numerous biotypes, which may differ from each other both genetically and biologically. only the b and q biotypes have been reported from israel. secondary symbiont infection frequenci ...	2007	17645822
the role of wolbachia bacteria in the pathogenesis of onchocerciasis and prospects for control of the disease.	onchocerciasis, a non-fatal disease, is a major public health problem especially in sub-saharan africa causing disfigurement, severe itching, skin depigmentation, vision impairment and eventually blindness. the discovery of wolbachia intracellular bacteria in the filarial nematodes has contributed a lot to the understanding of host's immune response to the bacteria and its role in the pathogenesis of onchocericiasis. lipopolysaccharide molecules (lps) associated with the bacteria are responsible ...	2007	17642180
proinflammatory cytokine gene expression by murine macrophages in response to brugia malayi wolbachia surface protein.	wolbachia, an endosymbiotic bacterium found in most species of filarial parasites, is thought to play a significant role in inducing innate inflammatory responses in lymphatic filariasis patients. however, the wolbachia-derived molecules that are recognized by the innate immune system have not yet been identified. in this study, we exposed the murine macrophage cell line raw 264.7 to a recombinant form of the major wolbachia surface protein (rwsp) to determine if wsp is capable of innately induc ...	2007	17641731
extraordinary flux in sex ratio.	the ratio of males to females in a species is often considered to be relatively constant, at least over ecological time. hamilton noted that the spread of "selfish" sex ratio-distorting elements could be rapid and produce a switch to highly biased population sex ratios. selection against a highly skewed sex ratio should promote the spread of mutations that suppress the sex ratio distortion. we show that in the butterfly hypolimnas bolina the suppression of sex biases occurs extremely fast, with ...	2007	17626876
cytonuclear disequilibrium in chrysochus hybrids is not due to patterns of mate choice.	we investigated patterns of cytonuclear disequilibrium between nuclear allozyme loci and partial mitochondrial coi and coii restriction fragment length polymorphism patterns within a population of hybridizing chrysomelid beetles and assessed to what degree the genotype frequencies of f1 hybrids were consistent with patterns of mate choice or endosymbiont infection. we document that in this population, > or = 50% of the heterospecific pairs at a given time are composed of chrysochus auratus femal ...	2007	17621589
selection in the absence of males does not affect male-female conflict in the parasitoid wasp leptopilina clavipes (hymenoptera: figitidae).	divergent reproductive interests of males and females can lead to sexually antagonistic coevolution (sac). in the absence of males, adaptations evolved under sac are released from selection and expected to deteriorate. in this study, we investigated this prediction using two populations of the parasitoid wasp leptopilina clavipes, one arrhenotokous and one thelytokous. thelytokous females were induced to produce sons by curing them of their wolbachia-infection. we examined whether thelytokous ma ...	2007	17588599
new criteria for selecting the origin of dna replication in wolbachia and closely related bacteria.	the annotated genomes of two closely related strains of the intracellular bacterium wolbachia pipientis have been reported without the identifications of the putative origin of replication (ori). identifying the ori of these bacteria and related alpha-proteobacteria as well as their patterns of sequence evolution will aid studies of cell replication and cell density, as well as the potential genetic manipulation of these widespread intracellular bacteria.	2007	17584494
no influence of indy on lifespan in drosophila after correction for genetic and cytoplasmic background effects.	to investigate whether alterations in mitochondrial metabolism affect longevity in drosophila melanogaster, we studied lifespan in various single gene mutants, using inbred and outbred genetic backgrounds. as positive controls we included the two most intensively studied mutants of indy, which encodes a drosophila krebs cycle intermediate transporter. it has been reported that flies heterozygous for these indy mutations, which lie outside the coding region, show almost a doubling of lifespan. we ...	2007	17571923
molecular evidence for the endosymbiont wolbachia in a non-filaroid nematode, angiostrongylus cantonensis.	wolbachia harbored by most filarial parasites, is critical to both embryogenesis and microfilarial development, and may lead to inflammation and pathogenesis in infected hosts. based on alignment of the sequences from the wsp, ftsz, and 16s rrna genes, wolbachia was demonstrated to exist in angiostrongylus cantonensis, a non-filaroid nematode. although the wsp gene may not be the best candidate for evolutionary analysis of wolbachia, this gene has been sequenced from a broader coverage of the ho ...	2007	17562224
incidence of the endosymbionts wolbachia, cardinium and spiroplasma in phytoseiid mites and associated prey.	endosymbiotic bacteria that potentially influence reproduction and other fitness-related traits of their hosts are widespread in insects and mites and their appeal to researchers' interest is still increasing. we screened 20 strains of 12 agriculturally relevant herbivorous and predatory mite species for infection with wolbachia, cardinium and spiroplasma by the use of pcr. the majority of specimens originated from austria and were field collected or mass-reared. eight out of 20 strains (40%) te ...	2007	17554631
revisiting wolbachia supergroup typing based on wsp: spurious lineages and discordance with mlst.	the obligate intracellular bacteria wolbachia are taxonomically subdivided into eight supergroups (named a-h). supergroup typing of strains has been mostly based on phylogenetic inference of the wolbachia surface protein (wsp), a gene that recently has been shown to experience high rates of recombination. this brings into question its suitability not only for microtaxonomy, but also for supergroup classification of the genus. a multilocus sequence typing (mlst) scheme for wolbachia has recently ...	2007	17551786
maternal transmission of wolbachia in phlebotomus papatasi (scopoli).	attempts have been made to transfer wolbachia from infected to uninfected, laboratory-reared phlebotomus papatasi, through mating, and to determine whether the incompatibility phenotype could be expressed through crosses between infected and uninfected flies. in order to test for the intraspecific transmission of wolbachia in crosses between infected females and uninfected males, or those between uninfected females and infected males, a pcr based on wolbachia -specific wsp primers was used to te ...	2007	17550649
a natural population of the butterfly eurema hecabe with wolbachia-induced female-biased sex ratio not by feminization.	in butterflies, the adult sex ratio observed in the field is usually male-biased, although the sex ratio of their progeny is 1:1. this is due to the higher motility and larger behavioral range of males than females. as expected, the sex ratio of eurema hecabe butterflies collected at 6 localities throughout japan was male-biased. however, in tsukuba, located in the central part of japan, the sex ratio was found to be biased toward females. their progeny reared in the laboratory also exhibited a ...	2007	17546095
wolbachia-host interactions: connecting phenotype to genotype.	the long-established view of wolbachia as reproductive parasites of insects is becoming complicated as an increasing number of papers describe a richer picture of wolbachia-mediated phenotypes in insects. the search for the molecular basis for this phenotypic variability has been greatly aided by the recent sequencing of several wolbachia genomes. these studies have revealed putative genes and pathways that are likely to be involved in the host-symbiont interaction. whereas significant progress ...	2007	17537669
evidence for recombination between feminizing wolbachia in the isopod genus armadillidium.	wolbachia are maternally inherited endosymbiotic alpha-proteobacteria infecting a wide range of arthropods. wolbachia induce feminization in many terrestrial isopod species, particularly in the genus armadillidium (crustacea, oniscidea). the diversity of wolbachia strains infecting armadillidium species was examined. results reveal that natural populations of a. vulgare contain three different wolbachia strains (wvulc, wvulm and wvulp). the wsp gene and its 3'-adjacent region show evidence that ...	2007	17537593
bidirectional incompatibility among divergent wolbachia and incompatibility level differences among closely related wolbachia in nasonia.	most insect groups harbor obligate bacterial symbionts from the alpha-proteobacterial genus wolbachia. these bacteria alter insect reproduction in ways that enhance their cytoplasmic transmission. one of the most common alterations is cytoplasmic incompatibility (ci) - a post-fertilization modification of the paternal genome that renders embryos inviable or unable to complete diploid development in crosses between infected males and uninfected females or infected females harboring a different st ...	2007	17519968
influence of aging on cytoplasmic incompatibility, sperm modification and wolbachia density in culex pipiens mosquitoes.	wolbachia are maternally inherited endocellular bacteria, widespread in invertebrates and capable of altering several aspects of host reproduction. cytoplasmic incompatibility (ci) is commonly found in arthropods and induces hatching failure of eggs from crosses between wolbachia-infected males and uninfected females (or females infected by incompatible strains). several factors such as bacterial and host genotypes or bacterial density contribute to ci strength and it has been proposed, mostly f ...	2007	17519957
naturally occurring single and double infection with wolbachia strains in the butterfly eurema hecabe: transmission efficiencies and population density dynamics of each wolbachia strain.	wolbachia belonging to alphaproteobacteria are transovarially transmitted bacteria responsible for reproductive alterations in a wide range of arthropods. in natural populations of the butterfly eurema hecabe, there are two different types of wolbachia-infected individuals. individuals singly infected with wolbachia strain whecci exhibit strong cytoplasmic incompatibility, whereas those doubly infected with whecci and whecfem exhibit feminization. here, we examined the infection frequencies and ...	2007	17506822
unexpected mechanism of symbiont-induced reversal of insect sex: feminizing wolbachia continuously acts on the butterfly eurema hecabe during larval development.	when the butterfly eurema hecabe is infected with two different strains (whecci2 and whecfem2) of the bacterial endosymbiont wolbachia, genetic males are transformed into functional females, resulting in production of all-female broods. in an attempt to understand how and when the wolbachia endosymbiont feminizes genetically male insects, larval insects were fed an antibiotic-containing diet beginning at different developmental stages until pupation. when the adult insects emerged, strikingly, m ...	2007	17496135
prevalence of wolbachia infection in bemisia tabaci.	wolbachia are obligate intracellular bacteria present in reproductive tissues of many arthropod species. it has been reported that few silverleafing populations of bemisia tabaci were positive for wolbachia, whereas non-silverleafing populations were more likely infected with wolbachia and all that infect b. tabaci are wolbachia belonging to supergroup b. however, current detection methods were shown to be not sensitive enough to uncover all infections. herein, a protocol based on polymerase cha ...	2007	17487529
dna barcoding cannot reliably identify species of the blowfly genus protocalliphora (diptera: calliphoridae).	in dna barcoding, a short standardized dna sequence is used to assign unknown individuals to species and aid in the discovery of new species. a fragment of the mitochondrial gene cytochrome c oxidase subunit 1 is emerging as the standard barcode region for animals. however, patterns of mitochondrial variability can be confounded by the spread of maternally transmitted bacteria that cosegregate with mitochondria. here, we investigated the performance of barcoding in a sample comprising 12 species ...	2007	17472911
diversifying selection and host adaptation in two endosymbiont genomes.	the endosymbiont wolbachia pipientis infects a broad range of arthropod and filarial nematode hosts. these diverse associations form an attractive model for understanding host:symbiont coevolution. wolbachia's ubiquity and ability to dramatically alter host reproductive biology also form the foundation of research strategies aimed at controlling insect pests and vector-borne disease. the wolbachia strains that infect nematodes are phylogenetically distinct, strictly vertically transmitted, and r ...	2007	17470297
variability and expression of ankyrin domain genes in wolbachia variants infecting the mosquito culex pipiens.	wolbachia strains are maternally inherited endosymbiotic bacteria that infect many arthropod species and have evolved several different ways of manipulating their hosts, the most frequent way being cytoplasmic incompatibility (ci). ci leads to embryo death in crosses between infected males and uninfected females as well as in crosses between individuals infected by incompatible wolbachia strains. the mosquito culex pipiens exhibits the highest crossing type variability reported so far. our cross ...	2007	17449622
wolbachia-induced cytoplasmic incompatibility in japanese populations of tetranychus urticae (acari: tetranychidae).	intracellular bacteria of the genus wolbachia (alpha proteobacteria) induce cytoplasmic incompatibility (ci) in many arthropod species, including spider mites, but not all wolbachia cause ci. in spider mites ci becomes apparent by a reduced egg hatchability and a lower daughter:son ratio: ci in haplodiploid organisms in general was expected to produce all-male offspring or a male-biased sex ratio without any death of eggs. in a previous study of japanese populations of tetranychus urticae, two o ...	2007	17447012
from parasite to mutualist: rapid evolution of wolbachia in natural populations of drosophila.	wolbachia are maternally inherited bacteria that commonly spread through host populations by causing cytoplasmic incompatibility, often expressed as reduced egg hatch when uninfected females mate with infected males. infected females are frequently less fecund as a consequence of wolbachia infection. however, theory predicts that because of maternal transmission, these "parasites" will tend to evolve towards a more mutualistic association with their hosts. drosophila simulans in california provi ...	2007	17439303
wolbachia: invasion biology in south pacific butterflies.	wolbachia ensdosymbionts are well known for their ability to manipulate the population biology and development of their hosts. one of the less studied outcomes of wolbachia infection with this symbiont is the selective killing of male embryos. recent work on butterflies living on different south pacific islands is beginning to help us understand the complexity of the co-evolutionary interactions between these partners.	2007	17371764
presence of wolbachia in insect eggs containing antimicrobially active anthraquinones.	wolbachia are obligatory, cytoplasmatically inherited alpha-proteobacteria, which are common endosymbionts in arthropods where they may cause reproductive abnormalities. many insects are well known to protect themselves from deleterious microorganisms by antibiotic components. in this study, we addressed the question whether wolbachia are able to infect insects containing antimicrobial anthraquinones and anthrones, and if so, whether these genotypes of wolbachia comprise a monophyletic cluster w ...	2007	17364245
genetic diversity of costa rican populations of the rice planthopper tagosodes orizicolus (homoptera: delphacidae).	tagosodes orizicolus (homoptera: delphacidae) is one of the main constraints of the rice production in the neotropics. this planthopper produces severe damages as a phloem feeder, causes mechanical injury during oviposition and vectors the rice hoja blanca virus (rhbv). the main objective of this study was to determine the genetic diversity of t. orizicolus populations from three rice growing regions of costa rica, using rapds. individuals from guanacaste, parrita, san carlos and cali-colombia, ...	2004	17361572
molecular evidence and phylogenetic affiliations of wolbachia in cockroaches.		2007	17350292
taxonomic status of the intracellular bacterium wolbachia pipientis.	wolbachia pipientis is a maternally inherited, intracellular bacterium found in more than 20 % of all insects, as well as numerous other arthropods and filarial nematodes. it has been the subject of a growing number of studies in recent decades, because of the remarkable effects it has on its arthropod hosts, its potential as a tool for biological control of arthropods of agricultural and medical importance and its use as a target for treatment of filariasis. w. pipientis was originally discover ...	2007	17329802
brugia malayi wolbachia hsp60 igg antibody and isotype reactivity in different clinical groups infected or exposed to human bancroftian lymphatic filariasis.	wolbachia, an endosymbiotic bacterium in filarial parasites, comes into contact with the host immune system upon parasite death. here, we analyzed, total igg and isotype antibody responses to wolbachia hsp60 in individuals from an area endemic for wuchereria bancrofti. wolbachia derived hsp60 gene was cloned and the recombinant protein was used to determine the igg and isotype reactivity by western blotting and elisa. all individuals from the endemic area generated antibody responses to brugia m ...	2007	17306254
wolbachia-induced unidirectional cytoplasmic incompatibility and the stability of infection polymorphism in parapatric host populations.	wolbachia are intracellular, maternally inherited bacteria that are widespread among arthropods and commonly induce a reproductive incompatibility between infected male and uninfected female hosts known as unidirectional cytoplasmic incompatibility (ci). if infected and uninfected populations occur parapatrically, ci acts as a post-zygotic isolation barrier. we investigate the stability of such infection polymorphisms in a mathematical model with two populations linked by migration. we determine ...	2007	17305835
the evolution of endosymbiont density in doubly infected host species.	multiple infection of individual hosts with several species or strains of maternally inherited endosymbionts is commonly observed in animals, especially insects. here, we address theoretically the effect of co-infection on the optimal density of the endosymbionts in doubly infected hosts. our analysis is based on the observation that a maternally inherited double infection is only stable if doubly infected females produce more doubly infected daughters than singly infected or uninfected females ...	2007	17305834
disruption of the wolbachia surface protein gene wspb by a transposable element in mosquitoes of the culex pipiens complex (diptera, culicidae).	culex pipiens quinquefasciatus say and culex pipiens pipiens linnaeus are sibling species incriminated as important vectors of emerging and re-emerging infectious diseases worldwide. the two forms differ little morphologically and are differentiated mainly based upon ecological, behavioural, physiological and genetic traits. within the north american zone of sympatry, populations of cx. p. quinquefasciatus and cx. p. pipiens undergo extensive introgression and hybrid forms have been reported in ...	2007	17298560
correcting base-assignment errors in repeat regions of shotgun assembly.	accurate base-assignment in repeat regions of a whole genome shotgun assembly is an unsolved problem. since reads in repeat regions cannot be easily attributed to a unique location in the genome, current assemblers may place these reads arbitrarily. as a result, the base-assignment error rate in repeats is likely to be much higher than that in the rest of the genome. we developed an iterative algorithm, euler-air, that is able to correct base-assignment errors in finished genome sequences in pub ...	2007	17277413
male-killing bacteria trigger a cycle of increasing male fatigue and female promiscuity.	sex-ratio distorters are found in numerous species and can reach high frequencies within populations. here, we address the compelling, but poorly tested, hypothesis that the sex ratio bias caused by such elements profoundly alters their host's mating system. we compare aspects of female and male reproductive biology between island populations of the butterfly hypolimnas bolina that show varying degrees of female bias, because of a male-killing wolbachia infection. contrary to expectation, female ...	2007	17276921
fighting back against male-killers.	male-killing endosymbionts create a genetic black hole into which host nuclear genes vanish. in a recent paper, hornett et al. transferred male-killing wolbachia between different strains of the butterfly hypolimnas bolina through hybridization and backcrossing. their results provide unambiguous evidence of genetic variation for resistance to male-killers. a possible consequence of such variation is that male-killing might appear and disappear quickly on an evolutionary timescale.	2007	17276538
onchocerca volvulus, wolbachia and river blindness.	chronic infection with filarial nematodes results in development of a suppressive response to an immense parasite burden, thereby limiting pathological and clinical manifestations. however, pro-inflammatory responses to dead and degenerating onchocerca volvulus worms and release of endosymbiotic wolbachia bacteria result in corneal opacification, sacrification and visual impairment. this review discusses host and parasite factors implicated in maintaining this balance of pro- an anti-inflammator ...	2007	17264501
lack of resistance after re-exposure of cattle cured of onchocerca ochengi infection with oxytetracycline.	although vector control and ivermectin chemotherapy have led to a dramatic reduction in the incidence of river blindness (onchocerciasis), there is a consensus that additional control tools are required to sustain and extend this success. the recognition of endosymbiotic bacteria (wolbachia) in filariae and their targeting by antibiotics constitutes the most significant and practicable opportunity for a macrofilaricidal therapy in the short-to-medium-term. using onchocerca ochengi in cattle, an ...	2007	17255232
wolbachia in filarial parasites: targets for filarial infection and disease control.	lymphatic filariasis and onchocerciasis are debilitating diseases caused by parasitic filarial nematodes. these nematodes have evolved a mutualistic symbiosis with intracellular bacteria of the genus wolbachia, which are required for nematode embryogenesis and survival. the essential role of these bacteria in the biology of the nematode and their demonstrated involvement in the pathogenesis of filariasis make wolbachia a promising novel chemotherapeutic target for the control of filarial infecti ...	2007	17254505
disrupting the timing of wolbachia-induced male-killing.	several lineages of maternally inherited symbionts have evolved the ability to kill infected females' sons, a phenomenon known as male-killing. male-killing varies in its timing, from early (death during embryogenesis) to late (mortality of late larval instars). following the observation that treatment of male-killer infected adult females hypolimnas bolina with tetracycline, a bacteriostatic antibiotic, produces a delay in the timing of male death, we hypothesized that early male-killers posses ...	2007	17251127
interaction between host genotype and environmental conditions affects bacterial density in wolbachia symbiosis.	regulation of microbial population density is a necessity in stable symbiotic interactions. in wolbachia symbiosis, both bacterial and host genotypes are involved in density regulation, but environmental factors may also affect bacterial population density. here, we studied the interaction between three strains of wolbachia in two divergent homozygous lines of the wasp leptopilina heterotoma at two different temperatures. wolbachia density varied between the two host genotypes at only one temper ...	2007	17251124
wolbachia surface protein (wsp) inhibits apoptosis in human neutrophils.	polymorphonuclear cells (pmns) are essential for the innate immune response against invading bacteria. at the same time, modulation of pmns' apoptosis or cell death by bacteria has emerged as a mechanism of pathogenesis. wolbachia bacteria are gram-negative endosymbionts of filarial nematodes and arthropods, phylogenetically related to the genera anaplasma, ehrlichia and neorickettsia (family anaplasmataceae). although several pathogens are known to interfere with apoptosis, there is only limite ...	2007	17241395
symbiotic bacteria in oocyte and ovarian cell mitochondria of the tick ixodes ricinus: biology and phylogenetic position.	under natural conditions, eukaryote cells may contain bacteria. arthropods such as ticks, insects or mites are a group particularly favoured by the obligate intracellular bacteria. while arthropods are vectors for some of them, other bacteria inhabit invertebrate host cells having entered mutualistic interactions. such endosymbionts dwell usually in the host cell vacuoles or cytoplasm but have been also reported from tick oocyte mitochondria. the microorganisms contribute to mitochondria degrada ...	2007	17226040
molecular phylogeography of two sibling species of eurema butterflies.	the common yellow butterfly eurema hecabe is widely distributed in east asia, and is one of the most burdensome species for taxonomists due to the numerous geographic and seasonal wing colour patterns. moreover, within this species, individuals with a yellow wing fringe that occur in temperate regions of japan (y type) proved to be biologically different from others that occur widely in subtropical regions of japan and all over east asia (b type). to unveil the genetic variation within and betwe ...	2007	17216550
immunopathology of dirofilaria immitis infection.	heartworm disease caused by dirofilaria immitis affects canine and feline hosts, with infections occasionally being reported in humans. studies have shown that both dirofilarial antigens and those derived from its bacterial endosymbiont wolbachia, interact with the host organism during canine, feline and human infections and participate in the development of the pathology and in the regulation of the host's immune response. both innate and acquired immune responses are observed and the developme ...	2007	17216316
innate immune responses to endosymbiotic wolbachia bacteria in brugia malayi and onchocerca volvulus are dependent on tlr2, tlr6, myd88, and mal, but not tlr4, trif, or tram.	the discovery that endosymbiotic wolbachia bacteria play an important role in the pathophysiology of diseases caused by filarial nematodes, including lymphatic filariasis and onchocerciasis (river blindness) has transformed our approach to these disabling diseases. because these parasites infect hundreds of millions of individuals worldwide, understanding host factors involved in the pathogenesis of filarial-induced diseases is paramount. however, the role of early innate responses to filarial a ...	2007	17202370
parasitic inhibition of cell death facilitates symbiosis.	symbiotic microorganisms have had a large impact on eukaryotic evolution, with effects ranging from parasitic to mutualistic. mitochondria and chloroplasts are prime examples of symbiotic microorganisms that have become obligate for their hosts, allowing for a dramatic extension of suitable habitats for life. out of the extraordinary diversity of bacterial endosymbionts in insects, most are facultative for their hosts, such as the ubiquitous wolbachia, which manipulates host reproduction. some e ...	2007	17190825
competing selfish genetic elements in the butterfly hypolimnas bolina.	maternally inherited selfish genetic elements are common in animals . whereas host genetics and ecology are recognized as factors that may limit the incidence of these parasites , theory suggests one further factor-interference with other selfish elements-that could affect their prevalence . in this paper, we show that spatial heterogeneity in the occurrence of the male-killing wolbachia wbol1 in the tropical butterfly hypolimnas bolina is caused by a second infection that can exclude the male-k ...	2006	17174921
phylogenetic diversity of the intracellular symbiont wolbachia in termites.		2007	17174110
intergenomic epistasis for fitness: within-population interactions between cytoplasmic and nuclear genes in drosophila melanogaster.	the symbiotic relationship between the mitochondrial and nuclear genomes coordinates metabolic energy production and is fundamental to life among eukaryotes. consequently, there is potential for strong selection to shape interactions between these two genomes. substantial research attention has focused on the possibility that within-population sequence polymorphism in mitochondrial dna (mtdna) is maintained by mitonuclear fitness interactions. early theory predicted that selection will often eli ...	2007	17151264
the impact of male-killing bacteria on host evolutionary processes.	male-killing bacteria are maternally inherited endosymbionts that selectively kill male offspring of their arthropod hosts. using both analytical techniques and computer simulations, we studied the impact of these bacteria on the population genetics of their hosts. in particular, we derived and corroborated formulas for the fixation probability of mutant alleles, mean times to fixation and fixation or extinction, and heterozygosity for varying male-killer prevalence. our results demonstrate that ...	2007	17151259
infection density of wolbachia endosymbiont affected by co-infection and host genotype.	infection density is among the most important factors for understanding the biological effects of wolbachia and other endosymbionts on their hosts. to gain insight into the mechanisms of infection density regulation, we investigated the adzuki bean beetles callosobruchus chinensis and their wolbachia endosymbionts. double-infected, single-infected and uninfected host strains with controlled nuclear genetic backgrounds were generated by introgression, and infection densities in these strains were ...	2005	17148240
inos expression is stimulated by the major surface protein (rwsp) from wolbachia bacterial endosymbiont of dirofilaria immitis following subcutaneous injection in mice.	the bacterial endosymbiont wolbachia of several species of filarial nematodes plays an important role in the inflammatory pathology of filariasis. nitric oxide (no) production has also been implicated in the immune response during filarial infections. here we present data indicating that a recombinant wolbachia surface protein (rwsp) induces inos mrna expression and no production, as well as ifn-gamma and a th1-type antibody response, in inoculated balb/c mice. this effect is not observed when m ...	2007	17126589
effects of wolbachia in the uzifly, exorista sorbillans, a parasitoid of the silkworm, bombyx mori.	the uzifly, exorista sorbillans (diptera: tachinidae), a parasitoid of the silkworm, bombyx mori l. (lepidoptera: bombycidae), harbours wolbachia (rickettsia) endosymbionts. administration of 0.05 mg/ml oxytetracycline to the adult uziflies removed wolbachia endosymbionts and resulted in different reproductive disorders, such as i) reduction in fecundity of uninfected females, ii) cytoplasmic incompatibility in crosses between infected males and uninfected females, iii) sterility in the crosses ...	2005	17119612
a niche for wolbachia.	wolbachia are endosymbionts of arthropods and filarial nematodes. arthropods infected with these endobacteria display altered reproductive phenotypes, including cytoplasmic incompatibility and sex-ratio distortion. in nematodes, the endobacteria are essential for embryogenesis and worm survival. wolbachia are transmitted vertically from mother to progeny, and frydman et al. recently showed that, after transfer to uninfected drosophila, wolbachia rapidly accumulate in the somatic stem cell niche. ...	2007	17113827
evolution and invasion dynamics of multiple infections with wolbachia investigated using matrix based models.	endosymbiotic bacteria are often transmitted vertically from one host generation to the next via oocytes cytoplasm. the generally small number of colonizing bacteria in the oocytes leads to a bottleneck at each generation, resulting in genetic homogenization of the symbiotic population. nevertheless, in many of the species infected by wolbachia (maternally transmitted bacteria), individuals do sometimes simultaneously harbor several bacterial strains, owing to the fact that wolbachia induces cyt ...	2007	17112544
a survey of the bacteriophage wo in the endosymbiotic bacteria wolbachia.	bacteriophages are common viruses infecting prokaryotes. in addition to their deadly effect, phages are also involved in several evolutionary processes of bacteria, such as coding functional proteins potentially beneficial to them, or favoring horizontal gene transfer through transduction. the particular lifestyle of obligatory intracellular bacteria usually protects them from phage infection. however, wolbachia, an intracellular alpha-proteobacterium, infecting diverse arthropod and nematode sp ...	2007	17095536
co-cladogenesis spanning three phyla: leafhoppers (insecta: hemiptera: cicadellidae) and their dual bacterial symbionts.	endosymbioses are a major form of biological complexity affecting the ecological and evolutionary diversification of many eukaryotic groups. these associations are exemplified by nutritional symbioses of insects for which phylogenetic studies have demonstrated numerous cases of long-term codiversification between a bacterial and a host lineage. some insects, including most leafhoppers (insecta: hemiptera: cicadellidae), have more than one bacterial symbiont within specialized host cells, raising ...	2006	17054511
supergroup f wolbachia bacteria parasitise lice (insecta: phthiraptera).	we studied six species of lice from three of the four suborders of lice. these lice were infected with wolbachia bacteria from supergroups a and f. this is the first report of an infection of supergroup f wolbachia in lice. to date, wolbachia from supergroup f have been found in filarial nematodes, mansonella spp., and, rarely, in insects. we inferred the phylogeny of the wolbachia from lice and representatives of all wolbachia supergroups, with nucleotide sequences from the small subunit riboso ...	2007	17048002
effects of temephos and temperature on wolbachia load and life history traits of aedes albopictus.	maternally inherited wolbachia (gram-negative bacteria) often affect the reproductive fitness of their arthropod hosts and may cause cytoplasmic incompatibility (ci). comparing wolbachia-infected and uninfected strains of the mosquito aedes albopictus (skuse) (diptera: culicidae), we assessed the effects on fitness of two stressors: temperature elevation (25 degrees c vs. 37 degrees c) and exposure to temephos insecticide (concentration range 0.0017-0.0167 mg/l) during larval development. fitnes ...	2006	17044881
doxycycline reduces plasma vegf-c/svegfr-3 and improves pathology in lymphatic filariasis.	lymphatic filariasis is a disease of considerable socioeconomic burden in the tropics. presently used antifilarial drugs are able to strongly reduce transmission and will thus ultimately lower the burden of morbidity associated with the infection, however, a chemotherapeutic principle that directly induces a halt or improvement in the progression of the morbidity in already infected individuals would constitute a major lead. in search of such a more-effective drug to complement the existing ones ...	2006	17044733
deep mtdna divergences indicate cryptic species in a fig-pollinating wasp.	figs and fig-pollinating wasps are obligate mutualists that have coevolved for ca. 90 million years. they have radiated together, but do not show strict cospeciation. in particular, it is now clear that many fig species host two wasp species, so there is more wasp speciation than fig speciation. however, little is known about how fig wasps speciate.	2006	17040562
increased male mating rate in drosophila is associated with wolbachia infection.	the maternally inherited bacterium wolbachia pipientis infects 25-75% of arthropods and manipulates host reproduction to improve its transmission. one way wolbachia achieves this is by inducing cytoplasmic incompatibility (ci), where crosses between infected males and uninfected females are inviable. infected males suffer reduced fertility through ci and reduced sperm production. however, wolbachia induce lower levels of ci in nonvirgin males. we examined the impact of wolbachia on mating behavi ...	2006	17040394
phylogenetic relationships of the wolbachia of nematodes and arthropods.	wolbachia are well known as bacterial symbionts of arthropods, where they are reproductive parasites, but have also been described from nematode hosts, where the symbiotic interaction has features of mutualism. the majority of arthropod wolbachia belong to clades a and b, while nematode wolbachia mostly belong to clades c and d, but these relationships have been based on analysis of a small number of genes. to investigate the evolution and relationships of wolbachia symbionts we have sequenced o ...	2006	17040125
toward a wolbachia multilocus sequence typing system: discrimination of wolbachia strains present in drosophila species.	among the diverse maternally inherited symbionts in arthropods, wolbachia are the most common and infect over 20% of all species. in a departure from traditional genotyping or phylogenetic methods relying on single wolbachia genes, the present study represents an initial multilocus sequence typing (mlst) analysis to discriminate closely related wolbachia pipientis strains, and additional data on sequence diversity in wolbachia. we report a new phylogenetic characterization of four genes (aspc, a ...	2006	17036209
cardinium symbionts cause cytoplasmic incompatibility in spider mites.	intracellular symbiotic bacteria belonging to the cytophaga-flavobacterium-bacteroides lineage have recently been described and are widely distributed in arthropod species. the newly discovered bacteria, named cardinium sp, cause the expression of various reproductive alterations in their arthropod hosts, including cytoplasmic incompatibility (ci), induction of parthenogenesis and feminization of genetic males. we detected 16s ribosomal dna sequences similar to those of cardinium from seven popu ...	2007	17035954
asymmetrical reinforcement and wolbachia infection in drosophila.	reinforcement refers to the evolution of increased mating discrimination against heterospecific individuals in zones of geographic overlap and can be considered a final stage in the speciation process. one the factors that may affect reinforcement is the degree to which hybrid matings result in the permanent loss of genes from a species' gene pool. matings between females of drosophila subquinaria and males of d. recens result in high levels of offspring mortality, due to interspecific cytoplasm ...	2006	17032063
can anopheles gambiae be infected with wolbachia pipientis? insights from an in vitro system.	wolbachia pipientis are maternally inherited endosymbionts associated with cytoplasmic incompatibility, a potential mechanism to drive transgenic traits into anopheles populations for malaria control. w. pipientis infections are common in many mosquito genera but have never been observed in any anopheles species, leading to the hypothesis that anopheles mosquitoes are incapable of harboring infection. we used an in vitro system to evaluate the ability of anopheles gambiae cells to harbor diverse ...	2006	17028229
high levels of serum thromboxane b2 are generated during human pulmonary dirofilariosis.	the canine parasite dirofilaria immitis can infect humans. patients with pulmonary dirofilariosis develop significantly higher thromboxane b2 levels than healthy individuals living in areas where dirofilariosis is endemic and in areas where dirofilariosis is not endemic. the possible role of wolbachia bacteria in the appearance of this eicosanoid is discussed.	2006	17028222
eosinophils contribute to killing of adult onchocerca ochengi within onchocercomata following elimination of wolbachia.	many filarial nematodes, including onchocerca volvulus (the cause of human 'river blindness'), have a mutually dependent relationship with wolbachia bacteria. there has been much interest in wolbachia as a chemotherapeutic target, since there are no macrofilaricidal drugs (i.e., lethal to adult worms) of low toxicity. using the bovine parasite o. ochengi, we previously demonstrated that combined intensive and intermittent (com) oxytetracycline treatment induces a sustained depletion of wolbachia ...	2006	16962357
interspecific transfer of bacterial endosymbionts between tsetse fly species: infection establishment and effect on host fitness.	tsetse flies (glossina spp.) can harbor up to three distinct species of endosymbiotic bacteria that exhibit unique modes of transmission and evolutionary histories with their host. two mutualist enterics, wigglesworthia and sodalis, are transmitted maternally to tsetse flies' intrauterine larvae. the third symbiont, from the genus wolbachia, parasitizes developing oocytes. in this study, we determined that sodalis isolates from several tsetse fly species are virtually identical based on a phylog ...	2006	16950907
survival of wolbachia pipientis in cell-free medium.	wolbachia pipientis is an obligate intracellular bacterium found in a wide range of invertebrate taxa. while over ecological timescales wolbachia infections are maintained by strict maternal inheritance, horizontal transfer events are common over evolutionary time. to be horizontally transferred between organisms, wolbachia bacteria must pass through and survive an extracellular phase. we used baclight live-dead staining, pcr, and fluorescence in situ hybridization to assess the ability for puri ...	2006	16950898
multilocus sequence typing system for the endosymbiont wolbachia pipientis.	the eubacterial genus wolbachia comprises one of the most abundant groups of obligate intracellular bacteria, and it has a host range that spans the phyla arthropoda and nematoda. here we developed a multilocus sequence typing (mlst) scheme as a universal genotyping tool for wolbachia. internal fragments of five ubiquitous genes (gatb, coxa, hcpa, fbpa, and ftsz) were chosen, and primers that amplified across the major wolbachia supergroups found in arthropods, as well as other divergent lineage ...	2006	16936055
evolution of male-killer suppression in a natural population.	male-killing bacteria are widespread in arthropods, and can profoundly alter the reproductive biology of their host species. here we detail the first case of complete suppression of a male killer. the nymphalid butterfly hypolimnas bolina is infected with a strain of the bacterium wolbachia, wbol1, which kills male host embryos in polynesian populations, but does not do so in many areas of southeast asia, where both males and female adults are naturally infected, and wbol1-infected females produ ...	2006	16933972
feminizing wolbachia in zyginidia pullula (insecta, hemiptera), a leafhopper with an xx/x0 sex-determination system.	zyginidia pullula is a grass-dwelling leafhopper characterized by a bisexual reproduction mode. in this species, some females collected in northern italy, when mated with males, gave origin to an exclusively female brood. here, we demonstrated that in these lineages an infection by a new strain of wolbachia pipientis-designated as wzygpul-was detected by amplifying and sequencing the wsp and 16s rrna genes. about half of the female progeny were characterized by intersexual phenotypes, i.e. showi ...	2006	16928646
f supergroup wolbachia in bush crickets: what do patterns of sequence variation reveal about this supergroup and horizontal transfer between nematodes and arthropods?	wolbachia pipientis, an intracellular, alpha-proteobacterium, is commonly found in arthropods and filarial nematodes. most infected insects are known to harbor strains of wolbachia from supergroups a or b, whereas supergroups c and d occur only in filarial nematodes. here, we present molecular evidence from two genes (ftsz and 16s rdna) that 2 orthopterans (the bush cricket species orocharis saltator and hapithus agitator; gryllidae: eneopterinae) are infected with wolbachia from the f supergrou ...	2007	16924406
paternal chromosome segregation during the first mitotic division determines wolbachia-induced cytoplasmic incompatibility phenotype.	the most common wolbachia-induced phenotype in insects is cytoplasmic incompatibility (ci), which occurs when sperm from infected males fertilize eggs from uninfected females. ci produces distinct phenotypes in three closely related haplo-diploid species of the genus nasonia: mortality in n. longicornis and n. giraulti, and conversion to male development in n. vitripennis. we demonstrate that the majority of ci-induced mortality occurs during embryogenesis and that the pattern of paternal chromo ...	2006	16912076
tracking factors modulating cytoplasmic incompatibilities in the mosquito culex pipiens.	wolbachia are maternally inherited endosymbiotic bacteria that infect many arthropod species and may induce cytoplasmic incompatibility (ci), resulting in abortive embryonic development. one wolbachia host, culex pipiens complex mosquitoes, displays high levels of variability in both ci crossing types (cytotypes) and dna markers. we report here an analysis of 14 mosquito strains, containing 13 wolbachia variants, and with 13 different cytotypes. cytotypes were wolbachia-dependent, as antibiotic ...	2006	16911221
the emerging diversity of rickettsia.	the best-known members of the bacterial genus rickettsia are associates of blood-feeding arthropods that are pathogenic when transmitted to vertebrates. these species include the agents of acute human disease such as typhus and rocky mountain spotted fever. however, many other rickettsia have been uncovered in recent surveys of bacteria associated with arthropods and other invertebrates; the hosts of these bacteria have no relationship with vertebrates. it is therefore perhaps more appropriate t ...	2006	16901827
cardinium symbionts induce haploid thelytoky in most clones of three closely related brevipalpus species.	bacterial symbionts that manipulate the reproduction of their host to increase their own transmission are widespread. most of these bacteria are wolbachia, but recently a new bacterium, named cardinium, was discovered that is capable of the same manipulations. in the host species brevipalpus phoenicis (acari: tenuipalpidae) this bacterium induces thelytoky by feminizing unfertilized haploid eggs. the related species b. obovatus and b. californicus are thelytokous too, suggesting that they reprod ...	2006	16900311
wolbachia transinfection in aedes aegypti: a potential gene driver of dengue vectors.	the endosymbiotic bacteria in the genus wolbachia are capable of inducing a wide range of reproductive abnormalities in their hosts, including cytoplasmic incompatibility (ci), which could lead to the replacement of uninfected host populations with infected ones. because of this, wolbachia have attracted considerable interest as a potential mechanism for spreading disease-blocking transgenes through vector populations. here we report the establishment of double wolbachia transinfection by direct ...	2006	16895998
parallel infection of japanese encephalitis virus and wolbachia within cells of mosquito salivary glands.	the endosymbiont wolbachia usually causes cytoplasmic incompatibility in dipteran hosts, including mosquitoes. however, some important arbovirus-transmitting mosquitoes such as aedes aegypti (l.) are not heritably infected by wolbachia. in wolbachia-harboring mosquito armigeres subalbatus coquillett, colocalization of wolbachia and inoculated japanese encephalitis virus (family flaviviridae, genus flavivirus, jev) in salivary gland (sg) cells was shown by electron microscopy. the infection rate ...	2006	16892635
geographic distribution of wolbachia infections in cimex lectularius (heteroptera: cimicidae).	endosymbiotic wolbachia bacteria have been previously shown to infect laboratory colonies of the human bed bug, cimex lectularius l. (heteroptera: cimicidae), but little information exists regarding the extent of infection in natural populations. we assayed c. lectularius populations from five north american regions (california, connecticut, florida, new york, and toronto, canada) and one african region (macha, zambia) for wolbachia infection by the polymerase chain reaction (pcr). wolbachia inf ...	2006	16892626
wolbachia effects on aedes albopictus (diptera: culicidae) immature survivorship and development.	wolbachia bacteria manipulate the reproduction of mosquito hosts via a form of sterility known as cytoplasmic incompatibility (ci), promoting the spread of infections into host populations. the rate at which an infection invades is affected by host fitness costs associated with the wolbachia infection. here, we examine for an effect of wolbachia infection on the immature fitness of the asian tiger mosquito aedes albopictus (skuse) (diptera: culicidae). in two experiments, we examine for a wolbac ...	2006	16892625
isolation of wuchereria bancrofti microfilariae from archived stained blood slides for use in genetic studies and amplification of parasite and endosymbiont genes.	information on change in genetic diversity of wuchereria bancrofti is important in view of the launching of the global lymphatic filariasis elimination programme, as it may have important consequences on the control operations and on the potential resurgence after their withdrawal. since attention was not paid to generate such information when the programme was launched, use of archived parasite material will provide an opportunity to derive this information in a prospective manner. in this pape ...	2006	16860767
fitness effects of wolbachia and spiroplasma in drosophila melanogaster.	maternally inherited endosymbionts that manipulate the reproduction of their insect host are very common. aside from the reproductive manipulation they produce, the fitness of these symbionts depends in part on the direct impact they have on the female host. although this parameter has commonly been investigated for single infections, it has much more rarely been established in dual infections. we here establish the direct effect of infection with two different symbionts exhibiting different rep ...	2006	16850225
bacteriophage wo-b and wolbachia in natural mosquito hosts: infection incidence, transmission mode and relative density.	bacteriophages of wolbachia bacteria have been proposed as a potential transformation tool for genetically modifying mosquito vectors. in this study, we report the presence of the wo-b class of wolbachia-associated phages among natural populations of several mosquito hosts. eighty-eight percent (22/25) of wolbachia-infected mosquito species surveyed were found to contain wo-b phages. wo-b phage orf7 sequence analysis suggested that a single strain of wo-b phage was found in most singly (23/24) o ...	2006	16842419
asymmetrical interactions between wolbachia and spiroplasma endosymbionts coexisting in the same insect host.	we investigated the interactions between the endosymbionts wolbachia pipientis strain wmel and spiroplasma sp. strain nsro coinfecting the host insect drosophila melanogaster. by making use of antibiotic therapy, temperature stress, and hemolymph microinjection, we established the following strains in the same host genetic background: the sw strain, infected with both spiroplasma and wolbachia; the s strain, infected with spiroplasma only; and the w strain, infected with wolbachia only. the infe ...	2006	16820474
wolbachia endosymbiotic bacteria of brugia malayi mediate macrophage tolerance to tlr- and cd40-specific stimuli in a myd88/tlr2-dependent manner.	lymphatic filarial nematodes are able to down-regulate parasite-specific and nonspecific responses of lymphocytes and apc. lymphatic filariae are reliant on wolbachia endosymbiotic bacteria for development and survival. we tested the hypothesis that repeated exposure to wolbachia endosymbionts would drive macrophage tolerance in vitro and in vivo. we pre-exposed murine peritoneal-elicited macrophages to soluble extracts of brugia malayi female worms (bmfe) before restimulating with bmfe or tlr a ...	2006	16818783
the infective larva of litomosoides yutajensis guerrero et al., 2003 (nematoda: onchocercidae), a wolbachia-free filaria from bat.	the infective larva of litomosoides yutajensis guerrero et al., 2003, a parasite of the bat pteronotus pamellii, is described; it is distinct from congeneric infective larvae by the absence of caudal lappets. the life cycles of five other species of litomosoides are known; three are parasites of rodents, one of a marsupial and one of a bat. as with these species, the experimental vector of l. yutoajensis used was the macronyssid mite ornithonyssus bacoti. in nature, the main vectors are probably ...	2006	16800120
heritable endosymbionts of drosophila.	although heritable microorganisms are increasingly recognized as widespread in insects, no systematic screens for such symbionts have been conducted in drosophila species (the primary insect genetic models for studies of evolution, development, and innate immunity). previous efforts screened relatively few drosophila lineages, mainly for wolbachia. we conducted an extensive survey of potentially heritable endosymbionts from any bacterial lineage via pcr screens of mature ovaries in 181 recently ...	2006	16783009
wolbachia infection reduces sperm competitive ability in an insect.	the maternally inherited bacterium wolbachia pipientis imposes significant fitness costs on its hosts. one such cost is decreased sperm production resulting in reduced fertility of male drosophila simulans infected with cytoplasmic incompatibility (ci) inducing wolbachia. we tested the hypothesis that wolbachia infection affects sperm competitive ability and found that wolbachia infection is indeed associated with reduced success in sperm competition in non-virgin males. in the second male role, ...	2006	16777737
a wolbachia-associated fitness benefit depends on genetic background in drosophila simulans.	the alpha-proteobacteria wolbachia infect a number of insect species and influence host reproduction to favour the spread of infected females through a population. the fitness effect of this infection is important in understanding the spread and maintenance of wolbachia within and among host populations. however, a full elucidation of fitness effect requires careful control of host genetic background. here, i transferred a single clone of wolbachia (the wha strain) into three genetically distinc ...	2006	16777731
interspecific transfer of wolbachia into the mosquito disease vector aedes albopictus.	intracellular wolbachia bacteria are obligate, maternally inherited endosymbionts found frequently in insects and other invertebrates. the evolutionary success of wolbachia is due in part to an ability to manipulate reproduction. in mosquitoes and many other insects, wolbachia causes a form of sterility known as cytoplasmic incompatibility (ci). wolbachia-induced ci has attracted interest as a potential agent for affecting medically important disease vectors. however, application of the approach ...	2006	16777718
evolutionary history of a mosquito endosymbiont revealed through mitochondrial hitchhiking.	due to cytoplasmic inheritance, spread of maternally inherited wolbachia symbionts can result in reduction of mitochondrial variation in populations. we examined sequence diversity of the mitochondrial nadh dehydrogenase subunit 4 (nd4) gene in wolbachia-infected (south africa (sa), california and thailand) and uninfected (sa) culex pipiens complex populations. in total, we identified 12 haplotypes (a-l). in infected populations, 99% of individuals had haplotype k. in the uninfected sa populatio ...	2006	16769630
coffee berry borer hypothenemus hampei (coleoptera: curculionidae): searching for sustainable control strategies.	the coffee berry borer hypothenemus hampei (ferrari) is the most serious pest of the world's most valuable tropical export crop. since the last review on this insect was published six years ago, many new studies have contributed to an improved insight into the biology and ecology of the beetle, and have indicated new avenues for integrated and biological control. the latest developments in research, both laboratory and field, on the pest, its natural enemies and their implications for integrated ...	2006	16768810