Publications

discovery of protein-coding palindromic repeats in wolbachia.		2005	15936655
widespread prevalence of wolbachia in laboratory stocks and the implications for drosophila research.	wolbachia is an intracellular microbe harbored by a wide variety of arthropods (including drosophila) and filarial nematodes. employing several different strategies including male killing, induced parthenogenesis, cytoplasmic incompatibility, and feminization, and acting by as-yet-unknown mechanisms, wolbachia alters host reproduction to increase its representation within a population. wolbachia is closely associated with gametic incompatibility but also interacts with drosophila in other, littl ...	2005	15937134
generation of a novel wolbachia infection in aedes albopictus (asian tiger mosquito) via embryonic microinjection.	genetic strategies that reduce or block pathogen transmission by mosquitoes are being investigated as a means to augment current control measures. strategies of vector suppression and replacement are based upon intracellular wolbachia bacteria, which occur naturally in many insect populations. maternally inherited wolbachia have evolved diverse mechanisms to manipulate host insect reproduction and promote infection invasion. one mechanism is cytoplasmic incompatibility (ci) through which wolbach ...	2005	15944085
high divergence among drosophila simulans mitochondrial haplogroups arose in midst of long term purifying selection.	we characterize the type of selection acting within and among mitochondrial lineages in five closely related drosophila species. we focus on d. simulans, where three genetically distinct mitochondrial haplogroups show high interhaplogroup divergence and low intrahaplogroup polymorphism. using maximum likelihood models we find that the branches leading to these three distinct mitochondrial groups show a significantly reduced rate of nonsynonymous relative to synonymous substitution. this interhap ...	2005	15955513
anti-wolbachia treatment for lymphatic filariasis.		2005	15964428
macrofilaricidal activity after doxycycline treatment of wuchereria bancrofti: a double-blind, randomised placebo-controlled trial.	wolbachia endosymbionts of filarial nematodes are vital for larval development and adult-worm fertility and viability. this essential dependency on the bacterium for survival of the parasites has provided a new approach to treat filariasis with antibiotics. we used this strategy to investigate the effects of doxycycline treatment on the major cause of lymphatic filariasis, wuchereria bancrofti.	2005	15964448
effects of gamma radiation on brugia malayi infective larvae and their intracellular wolbachia bacteria.	prior studies have shown that irradiated filarial larvae are developmentally stunted but capable of inducing partial immunity to filariasis in animals. the mechanisms for these effects are poorly understood. recent studies suggest that intracellular wolbachia bacteria are necessary for the normal development, reproduction and survival of filarial nematodes. the purpose of this study was to examine the effects of irradiation on wolbachia in brugia malayi infective larvae (l3) and on l3 developmen ...	2005	15997407
lethal lps-independent side effects after microfilaricidal treatment in acanthocheilonema viteae-infected rodents.	mastomys coucha and jirds infected with acanthocheilonema viteae, a filarial species free of endosymbiontic bacteria of the genus wolbachia, suffer lethal side effects after effective microfilaricidal therapy with diethylcarbamazine and levamisole, whereas, m. coucha infected with the wolbachia-infested species brugia malayi or litomosoides carinii tolerate corresponding treatment. mortality in a. viteae infected, treated animals varied with microfilariae density in the blood. it was up to 100% ...	2005	15997410
new names for old strains? wolbachia wsim is actually wri.		2005	15998462
correction: serendipitous discovery of wolbachia genomes in multiple drosophila species.	a correction to serendipitous discovery of wolbachia genomes in multiple drosophila species by sl salzberg, jc dunning hotopp, al delcher, m pop, dr smith, mb eisen and wc nelson. genome biology 2005, 6:r23.	2005	15998463
parasite infiltrates fruitfly research.		2005	16001025
wolbachia genomes: insights into an intracellular lifestyle.	the genome sequence of the wolbachia endosymbiont that infects the nematode brugia malayi has recently been determined together with three partial wolbachia genomes from different drosophila species. these data along with the previously published wolbachia genome from drosophila melanogaster provide new insights into how this endosymbiont has managed to become so successful.	2005	16005284
entomology: incompatible mosquitoes.		2005	16015317
wolbachia variability and host effects on crossing type in culex mosquitoes.	wolbachia is a common maternally inherited bacterial symbiont able to induce crossing sterilities known as cytoplasmic incompatibility (ci) in insects. wolbachia-modified sperm are unable to complete fertilization of uninfected ova, but a rescue function allows infected eggs to develop normally. by providing a reproductive advantage to infected females, wolbachia can rapidly invade uninfected populations, and this could provide a mechanism for driving transgenes through pest populations. ci can ...	2005	16015330
distribution, expression, and motif variability of ankyrin domain genes in wolbachia pipientis.	the endosymbiotic bacterium wolbachia pipientis infects a wide range of arthropods, in which it induces a variety of reproductive phenotypes, including cytoplasmic incompatibility (ci), parthenogenesis, male killing, and reversal of genetic sex determination. the recent sequencing and annotation of the first wolbachia genome revealed an unusually high number of genes encoding ankyrin domain (ank) repeats. these ank genes are likely to be important in mediating the wolbachia-host interaction. in ...	2005	16030207
mosaic nature of the wolbachia surface protein.	lateral gene transfer and recombination play important roles in the evolution of many parasitic bacteria. here we investigate intragenic recombination in wolbachia bacteria, considered among the most abundant intracellular bacteria on earth. we conduct a detailed analysis of the patterns of variation and recombination within the wolbachia surface protein, utilizing an extensive set of published and new sequences from five main supergroups of wolbachia. analysis of nucleotide and amino acid seque ...	2005	16030235
can cytoplasmic incompatibility inducing wolbachia promote the evolution of mate preferences?	the maternally inherited bacterium, wolbachia pipientis, manipulates host reproduction by rendering uninfected females reproductively incompatible with infected males (cytoplasmic incompatibility, ci). hosts may evolve mechanisms, such as mate preferences, to avoid fitness costs of wolbachia infection. despite the potential importance of mate choice for wolbachia population dynamics, this possibility remains largely unexplored. here we model the spread of an allele encoding female mate preferenc ...	2005	16033569
sexual functionality of leptopilina clavipes (hymenoptera: figitidae) after reversing wolbachia-induced parthenogenesis.	females infected with parthenogenesis-inducing wolbachia bacteria can be cured from their infection by antibiotic treatment, resulting in male production. in most cases, however, these males are either sexually not fully functional, or infected females have lost the ability to reproduce sexually. we studied the decay of sexual function in males and females of the parasitoid leptopilina clavipes. in western europe, infected and uninfected populations occur allopatrically, allowing for an investig ...	2005	16033575
evidence for a global wolbachia replacement in drosophila melanogaster.	wolbachia are maternally inherited intracellular alpha-proteobacteria found in numerous arthropod and filarial nematode species. they influence the biology of their hosts in many ways. in some cases, they act as obligate mutualists and are required for the normal development and reproduction of the host. they are best known, however, for the various reproductive parasitism traits that they can generate in infected hosts. these include cytoplasmic incompatibility (ci) between individuals of diffe ...	2005	16085497
differential effects of diethylcarbamazine, tetracycline and the combination on brugia pahangi adult females in vitro.	anti-filarial effects of diethylcarbamazine (dec), tetracycline (tc) and the combination on brugia pahangi adult females were studied in 7-day cell-free culture, in terms of microfilaria release, parasite motility, mtt assay for parasite viability and embryogram. tc 50 microg/ml (tc50) effectively reduced microfilaria release from day 1 of culture. combined with dec 100 microg/ml (dec100) or dec 500 microg/ml (dec500), microfilaria release reduced further and synergistically. tc50 also reduced m ...	2005	16103005
detection and characterization of wolbachia infections in wuchereria bancrofti (spirurida: onchocercidae) var. pacifica and aedes (stegomyia) polynesiensis (diptera: culicidae).	despite control programs based on mass drug administration (mda) of microfilaricidal compounds, bancroftian lymphatic filariasis remains a problem in french polynesia. for an alternative strategy to mda, we investigated the potential role of wolbachia to control filarial transmission. wolbachia are intracellular alpha-proteobacteria endosymbionts that infect a broad range of insects and nematodes. these bacteria have a suspected role in the pathogenesis of filariasis. they also may be useful in ...	2005	16103603
wolbachia variant that induces two distinct reproductive phenotypes in different hosts.	wolbachia is an intracellular endosymbiont that induces a variety of reproductive alterations in diverse arthropods. the almond moth, cadra cautella, is double infected with two wolbachia variants, wcaua and wcaub, and expresses complete cytoplasmic incompatibility (ci). the individual contribution of wcaua and wcaub to the expression of ci are unclear, however, because the two variants have not been separated in this host. the effect of wcaua is of particular interest because it induces male ki ...	2005	16106260
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
pathogenesis and host responses in human onchocerciasis: impact of onchocerca filariae and wolbachia endobacteria.	onchocerca volvulus is a tissue-invasive parasitic nematode causing skin and eye pathology in human onchocerciasis. the filariae habour abundant intracellular wolbachia bacteria, now recognised as obligatory symbionts, and therefore emerging as a novel target for chemotherapy. recent research demonstrates that both the filariae and endobacteria contribute to the pathogenesis of onchocerciasis, and molecules have been identified that promote inflammatory or counter-inflammatory immune mechanisms, ...	2004	14738900
endosymbiosis: lessons in conflict resolution.		2004	15024418
phylogenomics of the reproductive parasite wolbachia pipientis wmel: a streamlined genome overrun by mobile genetic elements.	the complete sequence of the 1,267,782 bp genome of wolbachia pipientis wmel, an obligate intracellular bacteria of drosophila melanogaster, has been determined. wolbachia, which are found in a variety of invertebrate species, are of great interest due to their diverse interactions with different hosts, which range from many forms of reproductive parasitism to mutualistic symbioses. analysis of the wmel genome, in particular phylogenomic comparisons with other intracellular bacteria, has reveale ...	2004	15024419
wolbachia pipientis: intracellular infection and pathogenesis in drosophila.	wolbachia pipientis is a vertically transmitted, obligate intracellular symbiont of arthropods. the bacterium is best known for its ability to manipulate host reproductive biology where it can induce cytoplasmic incompatibility, parthenogenesis, feminization and male-killing. in addition to the various reproductive phenotypes it generates through interaction with host reproductive tissue it is also known to infect somatic tissues. however, relatively little is known about the consequences of inf ...	2004	15036143
mapping the presence of wolbachia pipientis on the phylogeny of filarial nematodes: evidence for symbiont loss during evolution.	wolbachia pipientis is a bacterial endosymbiont associated with arthropods and filarial nematodes. in filarial nematodes, w. pipientis has been shown to play an important role in the biology of the host and in the immuno-pathology of filariasis. several species of filariae, including the most important parasites of humans and animals (e.g. onchocerca volvulus, wuchereria bancrofti and dirofilaria immitis) have been shown to harbour these bacteria. other filarial species, including an important r ...	2004	15037105
natural wolbachia infections in the drosophila yakuba species complex do not induce cytoplasmic incompatibility but fully rescue the wri modification.	in this study, we report data about the presence of wolbachia in drosophila yakuba, d. teissieri, and d. santomea. wolbachia strains were characterized using their wsp gene sequence and cytoplasmic incompatibility assays. all three species were found infected with wolbachia bacteria closely related to the wau strain, found so far in d. simulans natural populations, and were unable to induce cytoplasmic incompatibility. we injected wri, a ci-inducing strain naturally infecting d. simulans, into t ...	2004	15238531
relationship of anti-microbial activity of tetracyclines to their ability to block the l3 to l4 molt of the human filarial parasite brugia malayi.	the nematode parasites wuchereria bancrofti, brugia malayi, and b. timori cause a human disease known as lymphatic filariasis, which afflicts approximately 120 million people worldwide. these organisms are known to contain endosymbiotic bacteria (wolbachia) that are related to rickettsiae. it has been previously reported that tetracycline blocks the l3 to l4 molt of the filarial parasite b. malayi, and suggested that this was related to their known anti-rickettsial activity. however, this interp ...	2004	15238684
fitness and life-history traits of the two major mitochondrial dna haplotypes of drosophila subobscura.	mitochondrial dna restriction site analyses on natural populations of drosophila subobscura have proved the existence of two common, coexisting haplotypes (i and ii), as well as a set of less frequent ones derived from them. to explain this distribution, experiments to date point practically to all possible genetic mechanisms being involved in the changes of gene frequencies (cytonuclear coadaptation, direct natural selection on mtdna and genetic drift). in an attempt to find differences that he ...	2004	15241444
impact of population age structure on wolbachia transgene driver efficacy: ecologically complex factors and release of genetically modified mosquitoes.	wolbachia symbionts hold theoretical promise as a way to drive transgenes into insect vector populations for disease prevention. for simplicity, current models of wolbachia dynamics and spread ignore ecologically complex factors such as the age structure of vector populations and overlapping vector generations. we developed a model including these factors to assess their impact on the process of wolbachia spread into populations of three mosquito species (anopheles gambiae, aedes aegypti and cul ...	2004	15242712
wolbachia and cytoplasmic incompatibility in mosquitoes.	wolbachia are maternally inherited bacteria that induce cytoplasmic incompatibility in mosquitoes, and are able to use these patterns of sterility to spread themselves through populations. for this reason they have been proposed as a gene drive system for mosquito genetic replacement, as well as for the reduction of population size or for modulating population age structure in order to reduce disease transmission. here, recent progress in the study of mosquito wolbachia is reviewed. we now have ...	2004	15242714
sexual differentiation traits in functional males with female genital apertures (male symbol fga) in the woodlice armadillidium vulgare latr. (isopoda, crustacea).	this study reports the results of examination of the gonadal morphology and ultrastructural features of the androgenic hormone (ah)-producing androgenic gland cells of laboratory stocks of functional male woodlice, armadillidium vulgare, with female genital apertures ( male symbol fga), with and without experimentally induced infections of the sex-ratio-distorting endobacterial parasite, wolbachia. males ( male symbol fga) have been reported in wild populations containing individuals infected wi ...	2004	15242750
reproductive effects and geographical distributions of two wolbachia strains infecting the neotropical beetle, chelymorpha alternans boh. (chrysomelidae, cassidinae).	wolbachia are maternally inherited endocellular bacteria known to alter insect host reproduction to facilitate their own transmission. multiple wolbachia infections are more common in tropical than temperate insects but few studies have investigated their dynamics in field populations. the beetle, chelymorpha alternans, found throughout the isthmus of panama, is infected with two strains of wolbachia, wcalt1 (99.2% of beetles) and wcalt2 (53%). populations infected solely by the wcalt1 strain we ...	2004	15245413
increased fecundity associated with infection by a cytophaga-like intracellular bacterium in the predatory mite, metaseiulus occidentalis.	the endosymbiont wolbachia has gained widespread notoriety over the past decade because of its high infection frequency among arthropods, and the unique heterogeneity of the host reproductive effects that it has been implicated as causing to enhance its own spread. recently, another endosymbiotic bacterium from the cytophaga-flavobacterium-bacteroides phylum has been shown to be widespread among arthropods and manipulate its hosts' reproduction to enhance its own spread. we show that infection b ...	2004	15252981
bacteriophage flux in endosymbionts (wolbachia): infection frequency, lateral transfer, and recombination rates.	the highly specialized genomes of bacterial endosymbionts typically lack one of the major contributors of genomic flux in the free-living microbial world-bacteriophages. this study yields three results that show bacteriophages have, to the contrary, been influential in the genome evolution of the most prevalent bacterial endosymbiont of invertebrates, wolbachia. first, we show that bacteriophage wo is more widespread in wolbachia than previously recognized, occurring in at least 89% (35/39) of t ...	2004	15254259
multiple displacement amplification in combination with high-fidelity pcr improves detection of bacteria from single females or eggs of metaseiulus occidentalis (nesbitt) (acari: phytoseiidae).	amplifying microbial dna by the polymerase chain reaction (pcr) from single phytoseiid mites has been difficult, perhaps due to the low titer of bacteria and to interference by the relatively larger amounts of mite genomic dna. in this paper we evaluate the efficiency of standard and high-fidelity pcr protocols subsequent to amplification of the whole genome by a multiple displacement amplification (mda) procedure developed by dean et al. dna from the phytoseiid phytoseiulus persimilis (athias-h ...	2004	15261775
life stages and reproductive components of the marmorkrebs (marbled crayfish), the first parthenogenetic decapod crustacean.	recently, we briefly reported on the first case of parthenogenesis in the decapod crustacea which was found in the marmorkrebs or marbled crayfish, a cambarid species of unknown geographic origin and species identity. curiously, this animal is known only from aquarium populations, where it explosively propagates. by means of light and electron microscopic techniques we have now investigated the reproductive components of this crayfish, using more than 100 specimens ranging from hatchling to repe ...	2004	15281058
population dynamics of wolbachia bacterial endosymbionts in brugia malayi.	the human filarial nematode brugia malayi contains an endosymbiotic bacterium, wolbachia. we used real-time quantitative polymerase chain reaction (qpcr) and microscopy to investigate the population dynamics of the bacterium-nematode association. two wolbachia (wsp and ftsz) and one nematode (gst) genes were amplified from all life-cycle stages of b. malayi and results expressed as gene copies per worm and as wolbachia/nematode ratios. since the genes were single copy and there was one genome pe ...	2004	15287587
wolbachia replication and host cell division in aedes albopictus.	wolbachia pipientis is an obligate intracellular endosymbiont of a range of arthropod species. the microbe is best known for its manipulations of host reproduction that include inducing cytoplasmic incompatibility, parthenogenesis, feminization, and male-killing. like other vertically transmitted intracellular symbionts, wolbachia's replication rate must not outpace that of its host cells if it is to remain benign. the mosquito aedes albopictus is naturally infected both singly and doubly with d ...	2004	15297923
variable fitness effects of wolbachia infection in drosophila melanogaster.	maternally inherited wolbachia bacteria are extremely widespread among insects and their presence is usually associated with parasitic modifications of host fitness. wolbachia pipientis infects drosophila melanogaster populations from all continents, but their persistence in this species occurs despite any strong parasitic effects. here, we have investigated the symbiosis between wolbachia and d. melanogaster and found that wolbachia infection can have significant survival and fecundity effects. ...	2004	15305172
[ultrastructural basis of interactions between prokaryotes and eukaryotes in different symbiotic models].	this paper reviews the author's contribution to the knowledge of the ultrastructural basis of the prokaryote-eukaryote interactions in different models assessed by an ultrastructural approach. in agreement with the hypothesis of the origin of eukaryotic cells, which are chimeras of several prokaryotes with different morpho-functional specializations, symbiosis had major consequence for evolution of life. in arthropods, one of the most successful lifestyles, the presence of endosymbiotic prokaryo ...	2004	15305681
multiple infection with wolbachia inducing different reproductive manipulations in the butterfly eurema hecabe.	wolbachia are rickettsial intracellular symbionts of arthropods and nematodes. in arthropods, they act as selfish genetic elements and manipulate host reproduction, including sex-ratio distortion and cytoplasmic incompatibility (ci). previous studies showed that infection of feminizing wolbachia and ci wolbachia sympatrically occurred in the butterfly eurema hecabe. we demonstrate that feminization-infecting individuals can rescue sperm modified by ci-infecting males. phylogenetic analysis revea ...	2004	15306297
use of wolbachia to drive nuclear transgenes through insect populations.	wolbachia is an inherited intracellular bacterium found in many insects of medical and economic importance. the ability of many strains to spread through populations using cytoplasmic incompatibility, involving sperm modification and rescue, provides a powerful mechanism for driving beneficial transgenes through insect populations, if such transgenes could be inserted into and expressed by wolbachia. however, manipulating wolbachia in this way has not yet been achieved. here, we demonstrate theo ...	2004	15306342
differential fitness of mitochondrial dna in perturbation cage studies correlates with global abundance and population history in drosophila simulans.	mitochondria are often referred to as the powerhouse of the cell. however, research linking intraspecific differences in organismal fitness with genotypic mitochondrial dna (mtdna) variation has been hampered by the lack of variation in experimentally tractable species. this study examines whether fly lines harbouring three distinct drosophila simulans mtdna types (sii, -ii and -iii) exhibit differential fitness in laboratory perturbation cages. comparison of the pre-perturbation and post-pertur ...	2004	15306370
molecular (sub) grouping of endosymbiont wolbachia infection among mosquitoes of taiwan.	wolbachia are maternally inherited bacteria that infect a wide range of arthropods as well as filarial worms. the infection usually results in reproductive distortions of the host, primarily cytoplasmic incompatibility, parthenogenesis, and feminization. this study showed that wolbachia infection (15/29; 51.72%) was prevalent among field-caught mosquitoes in taiwan. three mosquito species were identified as having wolbachia a infection, eight species as having wolbachia b, and four other species ...	2004	15311460
the bacterial catalase from filarial dna preparations derives from common pseudomonad contaminants and not from wolbachia endosymbionts.	wolbachia are obligatory endosymbionts in many species of filarial nematodes. certain bacterial molecules induce antibody responses in mammalian hosts infected with filariae, while others activate inflammatory responses that contribute to pathology. these findings, coupled with antibiotic studies demonstrating the dependence of filarial embryogenesis on the presence of wolbachia, have intensified research on wolbachia-nematode interactions, and the effects of wolbachia molecules on the mammalian ...	2004	15322925
cytogenetic mechanism and genetic consequences of thelytoky in the wasp trichogramma cacoeciae.	in hymenoptera, complete parthenogenesis, that is thelytoky, is a common phenomenon where virgin females produce only daughters. thelytoky is often induced by bacteria of the genus wolbachia, but can also be genetically determined by the insect itself, as in the genus trichogramma where both forms exist. in order to compare these two forms of thelytoky, chromosome behaviour analysis in young eggs and genetic analysis of microsatellite markers were carried out in the wasp trichogramma cacoeciae, ...	2004	15329666
parasites and sexual reproduction in psychid moths.	persistence of sexual reproduction among coexisting asexual competitors has been a major paradox in evolutionary biology. the number of empirical studies is still very limited, as few systems with coexisting sexual and strictly asexual lineages have been found. we studied the ecological mechanisms behind the simultaneous coexistence of a sexually and an asexually reproducing closely related species of psychid moth in central finland between 1999 and 2001. the two species compete for the same res ...	2004	15341153
heads or tails: host-parasite interactions in the drosophila-wolbachia system.	wolbachia strains are endosymbiotic bacteria typically found in the reproductive tracts of arthropods. these bacteria manipulate host reproduction to ensure maternal transmission. they are usually transmitted vertically, so it has been predicted that they have evolved a mechanism to target the host's germ cells during development. through cytological analysis we found that wolbachia strains display various affinities for the germ line of drosophila. different wolbachia strains show posterior, an ...	2004	15345422
a cost of wolbachia-induced sex reversal and female-biased sex ratios: decrease in female fertility after sperm depletion in a terrestrial isopod.	a number of parasites are vertically transmitted to new host generations via female eggs. in such cases, host reproduction is an intimate component of parasite fitness and no cost of the infection on host reproduction is expected to evolve. a number of these parasites distort host sex ratios towards females, thereby increasing either parasite fitness or the proportion of the host that transmit the parasite. in terrestrial isopods (woodlice), wolbachia bacteria are responsible for sex reversion a ...	2004	15347518
a new form of symbiotic bacteria wolbachia found in the endoplasmic reticulum of early embryos of drosophila melanogaster.		2004	15354833
coexistence of wolbachia with buchnera aphidicola and a secondary symbiont in the aphid cinara cedri.	intracellular symbiosis is very common in the insect world. for the aphid cinara cedri, we have identified by electron microscopy three symbiotic bacteria that can be characterized by their different sizes, morphologies, and electrodensities. pcr amplification and sequencing of the 16s ribosomal dna (rdna) genes showed that, in addition to harboring buchnera aphidicola, the primary endosymbiont of aphids, c. cedri harbors a secondary symbiont (s symbiont) that was previously found to be associat ...	2004	15375144
quantification of wolbachia bacteria in brugia malayi through the nematode lifecycle.		2004	15383308
wolbachia-induced neutrophil activation in a mouse model of ocular onchocerciasis (river blindness).	endosymbiotic wolbachia bacteria are abundant in the filarial nematodes that cause onchocerciasis (river blindness), including the larvae (microfilariae) that migrate into the cornea. using a mouse model of ocular onchocerciasis, we recently demonstrated that it is these endosymbiotic bacteria rather than the nematodes per se that induce neutrophil infiltration to the corneal stroma and loss of corneal clarity (saint andre et al., science 295:1892-1895, 2002). to better understand the role of wo ...	2004	15385467
wolbachia pipientis in australian spiders.	wolbachia pipientis is an endosymbiotic bacterium common to arthropods and filarial nematodes. this study presents the first survey and characterization of wolbachia pipientis that infect spiders. all spiders were collected from queensland, australia during 2002-2003 and screened for wolbachia infection using pcr approaches. the wolbachia strains present in the spiders are diverse, paraphyletic, and for the most part closely related to strains that infect insects. we have also identified several ...	2004	15386106
virulence, multiple infections and regulation of symbiotic population in the wolbachia-asobara tabida symbiosis.	the density and regulation of microbial populations are important factors in the success of symbiotic associations. high bacterial density may improve transmission to the next generation, but excessive replication could turn out to be costly to the host and result in higher virulence. moreover, differences in virulence may also depend on the diversity of symbionts. using the maternally transmitted symbiont wolbachia, we investigated how bacterial density and diversity are regulated and influence ...	2004	15454536
the genetic basis of male fertility in relation to haplodiploid reproduction in leptopilina clavipes (hymenoptera: figitidae).	traits under relaxed selection are expected to become reduced or disappear completely, a process called vestigialization. in parthenogenetic populations, traits historically involved in sexual reproduction are no longer under selection and potentially subject to such reduction. in leptopilina clavipes, thelytokous (parthenogenetic) populations are infected by wolbachia bacteria. arrhenotokous populations do not harbor wolbachia. when antibiotics are applied to infected females, they are cured fr ...	2004	15454547
wolbachia-induced cytoplasmic incompatibility as a means for insect pest population control.	biological control is the purposeful introduction of parasites, predators, and pathogens to reduce or suppress pest populations. wolbachia are inherited bacteria of arthropods that have recently attracted attention for their potential as new biocontrol agents. wolbachia manipulate host reproduction by using several strategies, one of which is cytoplasmic incompatibility (ci) [stouthamer, r., breeuwer, j. a. j. & hurst, g. d. d. (1999) annu. rev. microbiol. 53, 71-102]. we established wolbachia-i ...	2004	15469918
specific igg antibody response against antigens of dirofilaria immitis and its wolbachia endosymbiont bacterium in cats with natural and experimental infections.	sera from three groups of cats under different experimental conditions were studied by elisa to assess the host's immune response against synthetic peptides derived from dirofilaria immitis (dipp) and against the surface protein of its endosymbiont, wolbachia (wspr). in experimentally infected cats (group 1), an increase of igg antibody against both dipp and wspr was observed from 2 months post-infection until the end of the study, 6 months post-infection. in experimentally infected cats, treate ...	2004	15482887
wolbachia infection in the newly described ecuadorian sand flea, tunga trimamillata.	wolbachia pipientis is an intracellular endosymbiont producing reproductive alterations in its hosts. this bacterium have been reported in many arthropods and nematodes. by pcr amplification and sequencing of the 16s rdna and ftsz genes we have identified a wolbachia strain in the newly described sand-flea, tunga trimamillata. prevalence of this endosymbiont in the 26 individuals screened is equal to 35%. sympatric and allopatric specimens of the related species tunga penetrans were also analyse ...	2004	15491544
wolbachia effects in drosophila melanogaster: in search of fitness benefits.	insect endosymbionts often influence host nutrition but these effects have not been comprehensively investigated in wolbachia endosymbionts that are widespread in insects. using strains of drosophila melanogaster with the wmel wolbachia infection, we showed that wolbachia did not influence adult starvation resistance. wolbachia also had no effect on larval development time or the size of emerging adults from a low nutrition medium. while wolbachia may influence the expression of heat shock prote ...	2004	15491598
infection dynamics of different wolbachia-types within one host population.	wolbachia are widespread intracellular symbionts of arthropods which are known to cause several reproductive manipulations in their hosts, the commonest of which being cytoplasmic incompatibility (ci), male killing (mk), and the induction of parthenogenesis (pi). strains of endosymbionts inducing one of these effects can be referred to as 'wolbachia-types'. here, we try to ascertain whether two of these wolbachia-types can stably coexist within one population. we investigate this question by mea ...	2004	15501467
incipient evolution of wolbachia compatibility types.	cytoplasmic incompatibility (ci) is induced in arthropods by the maternally inherited bacterium wolbachia. when infected males mate with uninfected females or with females bearing a different wolbachia variant, paternal chromosomes behave abnormally and embryos die. this pattern can be interpreted as resulting from two bacterial effects: one (usually termed mod, for modification) would affect sperm and induce embryo death, unless wolbachia is also present in the egg, which implies the existence ...	2004	15521450
sequential evolution of a symbiont inferred from the host: wolbachia and drosophila simulans.	this study aims to unravel the biogeography of a model symbiont/host system by exploiting the prediction that a symbiont will leave a signature of infection on the host. specifically, a global sample of 1,442 drosophila simulans from 33 countries and 64 sampling localities was employed to infer the phylogeography of the maternally inherited alpha-proteobacteria wolbachia. phylogenetic analyses, from three symbiont genes and 24 mtdna genomes (excluding the a + t-rich region), showed that each of ...	2004	14660690
detection and phylogenetic analysis of wolbachia in collembola.	wolbachia are obligatory, cytoplasmatically inherited alpha-proteobacteria which are known for infecting the reproductive tissues of many arthropods. their prevalence in the large group of collembola, however, is not known, except for pcr detection in the parthenogenetically reproducing species folsomia candida (order: entomobryomorpha; family: isotomidae). in this study, fluorescence in situ hybridization on microscopic sections of f. candida specimens indicated that wolbachia-related bacteria ...	2004	14686939
most of the response elicited against wolbachia surface protein in filarial nematode infection is due to the infective larval stage.	immune responses to the intracellular wolbachia bacteria of filarial nematodes are thought to contribute to the pathologic process of filarial infection. here, we compare antibody responses of subjects living in an area where lymphatic filariasis is endemic with antibody responses elicited in a murine model of filarial infection, to provide evidence that the infective larval stage (l3), not adult nematodes, are the primary inducer of responses against wolbachia. in human subjects, antibody respo ...	2004	14702162
the role of endosymbiotic wolbachia bacteria in filarial disease.	in this review, we describe the pathogenic role of wolbachia endosymbiotic bacteria in filarial diseases, focusing on the host innate immune responses to filarial and wolbachia products. a description of the host pathogen recognition and early inflammatory responses including tlr4-mediated signalling, chemokine and cytokine responses and inflammatory cell recruitment is provided from human studies and from animal models of filarial disease. finally, the impact of the discovery and characterizati ...	2004	14706096
hierarchical scaffolding with bambus.	the output of a genome assembler generally comprises a collection of contiguous dna sequences (contigs) whose relative placement along the genome is not defined. a procedure called scaffolding is commonly used to order and orient these contigs using paired read information. this ordering of contigs is an essential step when finishing and analyzing the data from a whole-genome shotgun project. most recent assemblers include a scaffolding module; however, users have little control over the scaffol ...	2004	14707177
wolbachia transfer from rhagoletis cerasi to drosophila simulans: investigating the outcomes of host-symbiont coevolution.	wolbachia is an endosymbiont of diverse arthropod lineages that can induce various alterations of host reproduction for its own benefice. cytoplasmic incompatibility (ci) is the most common phenomenon, which results in embryonic lethality when males that bear wolbachia are mated with females that do not. in the cherry fruit fly, rhagoletis cerasi, wolbachia seems to be responsible for previously reported patterns of incompatibility between populations. here we report on the artificial transfer o ...	2004	14711652
intracellular symbionts and other bacteria associated with deer ticks (ixodes scapularis) from nantucket and wellfleet, cape cod, massachusetts.	the diversity of bacteria associated with the deer tick (ixodes scapularis) was assessed using pcr amplification, cloning, and sequencing of 16s rrna genes originating from seven ticks collected from nantucket island and wellfleet, cape cod, mass. the majority of sequences obtained originated from gram-negative proteobacteria. four intracellular bacteria were detected including strains of ehrlichia, rickettsia, and wolbachia and an organism related to intracellular insect symbionts from the cyto ...	2004	14711698
horizontal transmission of wolbachia by strepsipteran endoparasites? a response to noda et al., 2001.		2004	14717905
diversity, distribution and specificity of wo phage infection in wolbachia of four insect species.	the bacteriophage wo was recently characterized in wolbachia, a strictly intracellular bacterium that causes several reproductive alterations in its arthropod hosts. to gain insights into the phage-wolbachia relationships, we studied the phage presence among wolbachia infecting four insect species sharing several wolbachia strains, two drosophila and two of their parasitoid wasps. based on the phage sequence of orf7, we identified five different phages in six wolbachia strains. among these five ...	2004	15056362
opposite sex-specific effects of wolbachia and interference with the sex determination of its host ostrinia scapulalis.	in the adzuki bean borer, ostrinia scapulalis, the sex ratio in most progenies is 1 : 1. females from wolbachia-infected matrilines, however, give rise to all-female broods when infected and to all-male broods when cured of the infection. these observations had been interpreted as wolbachia-induced feminization of genetic males into functional females. here, we show that the interpretation is incorrect. females from both lines have a female karyotype with a wz sex-chromosome constitution while m ...	2004	15058435
cytology of wolbachia-induced parthenogenesis in leptopilina clavipes (hymenoptera: figitidae).	parthenogenesis induced by cytoplasmatically inherited wolbachia bacteria has been found in a number of arthropod species, mainly hymenoptera. previously, two different forms of diploidy restoration have been reported to underlie parthenogenesis induction in hymenoptera by wolbachia. both are a form of gamete duplication, but each differs in their timing. we investigated the cytology of the early embryonic development of a wolbachia-infected strain of the parasitoid wasp leptopilina clavipes and ...	2004	15060582
an initial survey for wolbachia (rickettsiales: rickettsiaceae) infections in selected california mosquitoes (diptera: culicidae).	knowledge of biogeographic variation in wolbachia infection rates and inferred susceptibility to infection among different mosquito taxa has fundamental implications for the design and successful application of wolbachia-based vector-borne disease control strategies. using a wolbachia-specific polymerase chain reaction assay, we tested 14 north american mosquito species in five genera (aedes, anopheles, culiseta, culex, and ochlerotatus) for wolbachia infection. wolbachia infections were only de ...	2004	15061286
genetic diversity and wolbachia infection of the drosophila parasitoid leptopilina clavipes in western europe.	wolbachia are maternally transmitted bacteria that alter their arthropod hosts' reproduction in various ways, including parthenogenesis induction (pi). wolbachia-induced parthenogenesis can have drastic effects on the genetic structure of its host because it potentially reduces populations to clones without genetic exchange. however, wolbachia-induced parthenogenesis does not inevitably result in a reduction of genetic variation of infected populations vs. uninfected populations, because the par ...	2004	15078450
persistence of an extreme sex-ratio bias in a natural population.	the sex ratio is a key parameter in the evolution and ecology of a species. selfish genetic elements that bias the sex ratio of affected individuals are well known and characterized, but their effect on populations has been considered limited, because either the element does not achieve high prevalence or the host rapidly evolves resistance to the distorting element, reducing its prevalence. we tested whether the host necessarily prevails by using a butterfly system where records from the early ...	2004	15087494
drosophila melanogaster, drosophila simulans: so similar yet so different.	during the last two decades, the two cosmopolitan species drosophila melanogaster and drosophila simulans have been compared with regard to numerous characteristics, ranging from their geographic distribution and ecology to their dna polymorphism. various traits have been compared, including morphology, physiology, sexual behavior, allozymes and other proteins, chromosomal inversions, mitochondrial and nuclear dna, transposable elements, wolbachia etc. such comparisons reveal similarities and di ...	2004	15088643
mitochondrial dna in the drosophila melanogaster complex.	mitochondrial dna in the complex drosophila melanogaster was among the first studied in metazoans. the variability of the molecule was extensively studied using restriction enzymes, gene sequence and recently sequence of the whole coding region. within the complex, seven major haplotypes have been described, one (me) in d. melanogaster, three in d. simulans (sii, siii, siiii), two in d. mauritiana (mai, maii), and one in d. sechellia (se). the molecular distance between the haplotypes is compris ...	2004	15088645
wolbachia infections in drosophila melanogaster and d. simulans: polymorphism and levels of cytoplasmic incompatibility.	wolbachia are endosymbiotic bacteria, widespread in terrestrial arthropods. they are mainly transmitted vertically, from mothers to offspring and induce various alterations of their hosts' sexuality and reproduction, the most commonly reported phenomenon being cytoplasmic incompatibility (ci), observed in drosophila melanogaster and d. simulans. basically, ci results in a more or less intense embryonic mortality, occurring in crosses between males infected by wolbachia and uninfected females. in ...	2004	15088646
isolation and characterization of the bacteriophage wo from wolbachia, an arthropod endosymbiont.	wolbachia is a group of obligate symbiotic bacteria found in many insects and other arthropods. the presence of wolbachia alters reproduction in the host, but the mechanisms are unknown. molecular biological studies of wolbachia have delayed significantly, and one of the reasons is the lack of transformation techniques of this bacterium. in the present study, bacteriophage particles were isolated from wolbachia for the first time. the purified phage had an isometric head that was approximately 4 ...	2004	15094394
construction of bacterial artificial chromosome libraries from the parasitic nematode brugia malayi and physical mapping of the genome of its wolbachia endosymbiont.	the parasitic nematode, brugia malayi, causes lymphatic filariasis in humans, which in severe cases leads to the condition known as elephantiasis. the parasite contains an endosymbiotic alpha-proteobacterium of the genus wolbachia that is required for normal worm development and fecundity and is also implicated in the pathology associated with infections by these filarial nematodes. bacterial artificial chromosome libraries were constructed from b. malayi dna and provide over 11-fold coverage of ...	2004	15111095
mechanisms of parasite-induced sex reversal in gammarus duebeni.	the amphipod gammarus duebeni is host to the feminising microsporidian parasite nosema granulosis that converts males into functional females. to test the hypothesis that the parasite acts through endocrine disruption we compared the morphology of the gonad and activity of the androgenic gland, which coordinates male sexual differentiation, in infected and uninfected animals. male gonad consisted of testis, seminal vesicle and vas deferens that was anchored to the genital papilla on segment 7. t ...	2004	15111096
fitness advantage and cytoplasmic incompatibility in wolbachia single- and superinfected aedes albopictus.	wolbachia are obligate, maternally inherited, intracellular bacteria that infect numerous insects and other invertebrates. wolbachia infections have evolved multiple mechanisms to manipulate host reproduction and facilitate invasion of naive host populations. one such mechanism is cytoplasmic incompatibility (ci) that occurs in many insect species, including aedes albopictus (asian tiger mosquito). the multiple wolbachia infections that occur naturally in a. albopictus make this mosquito a usefu ...	2004	15127087
natural interspecific and intraspecific horizontal transfer of parthenogenesis-inducing wolbachia in trichogramma wasps.	the intracellular bacterium wolbachia is one of the most common symbionts in arthropods and, because of its manipulative effects on host reproduction, is assumed to be an important factor in several evolutionary processes. these bacteria are mainly vertically transmitted from mother to daughter through the egg cytoplasm, and horizontal transmission is generally assumed to be rare. here, we show natural inter- and intraspecific horizontal transfer of parthenogenesis-inducing wolbachia between par ...	2004	15129961
evidence for a new feminizing wolbachia strain in the isopod armadillidium vulgare: evolutionary implications.	wolbachia are intracellular maternally inherited alpha-proteobacteria infecting a wide range of arthropods. in the common pill bug armadillidium vulgare, the known wolbachia strain is responsible for feminization of genetic males. we have investigated wolbachia diversity in 20 populations of a. vulgare from west and east europe, north africa and north america. a new wolbachia strain (wvulm) was identified through the variability of the wsp gene, distantly related to that previously known (wvulc) ...	2004	15138452
the sex ratio distortion in the human head louse is conserved over time.	at the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, pediculus humanus capitis, had been reported. a study by buxton in 1940 on the sex ratio of lice on prisoners in ceylon is still today the subject of reanalyses. this sex ratio distortion had been detected in ten different countries. in the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed ...	2004	15140268
pathogens and symbionts in ticks: prevalence of anaplasma phagocytophilum (ehrlichia sp.), wolbachia sp., rickettsia sp., and babesia sp. in southern germany.	tick-transmitted diseases like tick-borne encephalitis and lyme borreliosis have been well known in germany for decades. ongoing research now gives an additional focus to a broad range of other bacteria and parasites in ticks like anaplasma phagocytophilum, former ehrlichia sp., rickettsia sp. and babesia sp. knowledge about the prevalence of these infectious agents in ticks is an important prerequisite for risk assessment of human diseases. therefore nymphs and adult ixodes ricinus ticks were c ...	2004	15146989
wolbachia affects oviposition and mating behaviour of its spider mite host.	wolbachia bacteria are transmitted from mother to offspring via the cytoplasm of the egg. when mated to males infected with wolbachia bacteria, uninfected females produce unviable offspring, a phenomenon called cytoplasmic incompatibility (ci). current theory predicts that 'sterilization' of uninfected females by infected males confers a fitness advantage to wolbachia in infected females. when the infection is above a threshold frequency in a panmictic population, ci reduces the fitness of uninf ...	2004	15149411
strain-specific quantification of wolbachia density in aedes albopictus and effects of larval rearing conditions.	the density of the endosymbiont wolbachia can influence the expression of the crossing sterilities known as cytoplasmic incompatibility (ci), and also its rate of maternal transmission. aedes albopictus mosquitoes contain a superinfection with the wolbachia strains walba and walbb. a strain-specific real-time quantitative pcr assay was developed and used to quantify relative wolbachia strain densities within individual mosquitoes. the walbb strain was consistently found to be at higher density t ...	2004	15157232
new environments, versatile genomes.		2004	15181901
distribution of the bacterial symbiont cardinium in arthropods.	abstract 'candidatus cardinium', a recently described bacterium from the bacteroidetes group, is involved in diverse reproduction alterations of its arthropod hosts, including cytoplasmic incompatibility, parthenogenesis and feminization. to estimate the incidence rate of cardinium and explore the limits of its host range, 99 insect and mite species were screened, using primers designed to amplify a portion of cardinium 16s ribosomal dna (rdna). these arthropods were also screened for the presen ...	2004	15189221
the contribution by mitochondrially induced oxidative damage to aging in drosophila melanogaster.	strains of drosophila melanogaster have been generated that vary in the mitochondrial genome and have a common nuclear genome. tetracycline was used to cure the strains of the endocommensal bacteria, wolbachia, which is transmitted maternally. variation in the tetracycline responsive agent contributed substantially to variation in longevity and production of metabolic oxidants. changes in diurnal cycle of activity have been investigated: such changes should be responsive to metabolism-related da ...	2004	15190188
the major surface protein of wolbachia endosymbionts in filarial nematodes elicits immune responses through tlr2 and tlr4.	more than 150 million humans in tropical countries are infected by filarial nematodes which harbor intracellular bacterial endosymbionts of the genus wolbachia (rickettsiales). these bacteria have been implicated in adverse effects of drug treatment in filariasis. the present study provides evidence that purified major wolbachia surface protein (rwsp) acts as an inducer of the innate immune system through tlr2 and tlr4: 1) recombinant, stringently purified rwsp elicited the release of tnf-alpha, ...	2004	15210803
[structural organization and distribution of symbiotic bacteria wolbachia in early embryos and ovaries of drosophila melanogaster and d. simulans].	electron microscopic and morphometric analyses of wolbachia distribution in early embryos of drosophila flies have demonstrated that the number of bacteria in the embryo remains constant from fertilization to blastoderm, and that afterwards the symbionts could be observed only in the polar cells. each bacterium has a three-layer envelope, makes contacts with microtubules and moves through the cytoplasm following the actively dividing nuclei. it has been found for the first time that wolbachia co ...	2004	15214166
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
are filarial nematode wolbachia obligate mutualist symbionts?	the intracellular symbiotic bacteria of filarial nematodes have inspired new ideas for the control of disease using antibacterial drugs. for effective, long-term control, this requires that the bacteria are essential to their nematode hosts. two recent studies offer conflicting evidence: long, close coevolution between most filarial nematodes and their symbionts contrasts with many species having naturally lost them. an attempt to transfer symbionts to an uninfected host found that the bacteria ...	2004	16701248
analysis of sarcoptes scabiei finds no evidence of infection with wolbachia.	the endosymbiont wolbachia has been detected in a range of filarial nematodes and parasitic mites and is known to affect host reproductive compatibility and potentially evolutionary processes. pcr of wolbachia surface protein (wsp), ftsz and 16srrna genes from individual sarcoptes scabiei mites obtained from a series of individual hosts, and database searches of an s. scabiei var. hominis est library failed to detect wolbachia genes. therefore, wolbachia appears not to be involved in the genetic ...	2004	15710433