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Deteção e caracterização molecular das estirpes de Wolbachia nos afídeos

Moreira, Marta Abreu
Fonte: Universidade da Madeira Publicador: Universidade da Madeira
Tipo: Dissertação de Mestrado
Publicado em /09/2014 POR
Relevância na Pesquisa
37.56%
A Wolbachiapertence a um grupo de bactérias intracelulares, transmitidas maternalmente, que se encontram amplamente distribuídas nos artrópodes. Estes endossimbiontes encontram-se normalmente nos tecidos do sistema reprodutor dos artrópodes e têm a capacidade manipular a sua reproduçãode modo a garantir a sua transmissão à descendência e rápida dispersão na população.A capacidade de manipulação reprodutiva da Wolbachia tornou-a o alvo de diversos estudos para uma maior e melhor perceção da sua implicação em processos biológicos e evolutivos e por acreditar-se que esta bactéria é uma promissora ferramenta no controlo de populações de insetos que são pragas agrícolas. Os afídeos são um grupo de insetos associados às plantas que podem ter um efeito devastador nas culturas agrícolas e hortícolas pois não só retiram nutrientes às plantas como podem ser vetores de doenças. Embora durante muito tempo se pensasse que estes insetos não albergavam a Wolbachia estudos recentes mostram que são várias as espécies de afídeos infetados com esta bactéria. O principal objetivo deste trabalho é estudar a prevalência de infeção por Wolbachia assim como a caracterização das suas estirpes em amostras de afídeos dos Arquipélagos da Madeira e dos Açores. Neste estudo foram analisadas 545 amostras de afídeos...

Wolbachia in Anastrepha Fruit Flies (Diptera: Tephritidae)

COSCRATO, Virginia E.; BRAZ, Antonio S. K.; PERONDINI, Andre L. P.; SELIVON, Denise; MARINO, Celso L.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.53%
Endosymbiotic bacteria of the genus Wolbachia are widespread among arthropods and cause a variety of reproductive abnormalities, such as cytoplasmic incompatibility, thelytokous parthenogenesis, male-killing, and host feminization. In this study, we used three sets of Wolbachia-specific primers (16S rDNA, ftsZ, and wsp) in conjunction with the polymerase chain reaction (PCR), cloning and sequencing to study the infection of fruit flies (Anastrepha spp. and Ceratitis capitata) by Wolbachia. The flies were collected at several localities in Brazil and at Guayaquil, Ecuador. All of the fruit flies studied were infected with Wolbachia supergroup A, in agreement with the high prevalence of this group in South America. Phylogenetic analysis showed that the wsp gene was the most sensitive gene for studying the relationships among Wolbachia strains. The Wolbachia sequences detected in these fruit flies were similar to those such as wMel reported for other fruit flies. These results show that the infection of Anastrepha fruit flies by Wolbachia is much more widespread than previously thought.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[03/02693-4]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[03/00069-9]

Análise comparativa de Culex quinquefasciatus infectados e não infectados por Wolbachia pipientis.; Comparative analysis of Culex quinquefasciatus infected and non-infected by Wolbachia pipientis.

Almeida, Fabio de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/06/2008 PT
Relevância na Pesquisa
37.53%
Wolbachia é uma bactéria intracelular obrigatória, de transmissão vertical, encontrada em tecidos reprodutivos de muitos artrópodes e nematóides. Ela manipula o ciclo reprodutivo de seus hospedeiros, induzindo partenogênese, feminização, morte de machos e incompatibilidade citoplasmática. No intuito de verificar a existência de alterações reprodutivas em mosquitos Culex quinquefasciatus infectados por Wolbachia (cepa B), tratamos com antibiótico uma colônia infectada e obtivemos uma colônia livre da infecção. Os mosquitos de nossas colônias apresentam o fenômeno de incompatibilidade citoplasmática. Paralelamente, a infecção causa redução do número de ovos e diminui a mortalidade de larvas e pupas, fazendo com que o número de adultos emergidos seja estatisticamente igual entre os animais infectados e não infectados. Além disso, observamos que mosquitos coletados na natureza, na cidade de São Paulo, Brasil, estão infectados pela mesma cepa da bactéria.; Wolbachia is an obligatory intracellular bacterium, maternally inherited, found in reproductive tissues of many arthropods and nematodes. It manipulates the reproductive behavior of their hosts, inducing parthenogenesis, feminization, male-killing and cytoplasmic incompatibility. In order to verify the existence of reproductive manipulation in Culex quinquefasciatus mosquitoes infected with Wolbachia (B strain)...

Primeiro registro de Wolbachia (Proteobacteria, Rickettsiales) em isópodos terrestres na América do Sul : prevalência, aspectos filogenéticos de suas linhagens e seu possível impacto sobre a estrutura populacional estimada através de um loco mitocondrial em duas espécies do gênero Balloniscus (Crustacea: Oniscidea)

Almerão, Maurício Pereira
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
37.73%
Embora muitos aspectos sobre a história de vida dos isópodos terrestres na América do Sul tenham sido investigados, alguns ainda são desconhecidos. Entre estes, está a relação simbiótica entre os isópodos terrestres e Wolbachia pipientis, uma espécie de alpha-proteobactéria, considerada um parasito intracelular obrigatório que infecta espécies de nematóides e praticamente todos os grupos de artrópodos, incluindo os isópodos terrestres (Oniscidea). Apesar de contestada, a filogenia mais aceita inclui as linhagens de Wolbachia em oito supergrupos (A-H), a partir da qual a transmissão horizontal (entre taxons) é corroborada. Wolbachia está presente em vários tecidos do hospedeiro, principalmente em tecidos reprodutivos e propaga-se por via materna para a prole, utilizando como estratégia de disseminação, a produção de fêmeas ao longo das gerações. Esse aumento na proporção de fêmeas surge como consequência dos fenótipos induzidos gerados pela interação Wolbachia-hospedeiro. A cotransmissão de Wolbachia e outros elementos presentes no citoplasma (p. ex. mitocôndrias) gera um desequilíbrio de ligação entre os mesmos. Este fenômeno juntamente com a taxa de transmissão vertical, competição entre linhagens e ancestralidade da invasão são fatores que podem contribuir para alterações na estruturação do mtDNA nas populações hospedeiras. Todas essas características fazem de Wolbachia um fator que pode estar envolvido no processo de especiação. O presente trabalho descreve o primeiro registro de Wolbachia em espécies de isópodos terrestres endêmicas da América do Sul...

Aspectos da relação simbiótica entre as bactérias Wolbachia (Alphaproteobacteria, Rickettsiales) e os isópodos terrestres (Crustacea, Oniscidea)

Zimmermann, Bianca Laís
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.65%
Wolbachia é uma alfaproteobactéria que apresenta simbiose com uma variedade de artrópodos e nematoides, estando entre os mais abundantes gêneros de bactérias intracelulares já descobertos. Na região Neotropical, os estudos sobre tais bactérias e seus hospedeiros, em especial isópodos terrestres, ainda são incipientes. O presente trabalho teve como objetivos: investigar as espécies de isópodos terrestres neotropicais infectados por Wolbachia; analisar a prevalência de infecção, variação genética e relações filogenéticas das linhagens presentes nessas espécies; investigar a simbiose de Wolbachia em nematoides parasitos de tatuzinhos-de-jardim e inferir sobre as possíveis rotas de transmissão horizontal da bactéria entre os isópodos terrestres e os invertebrados que possuam associações ecológicas com os mesmos. A detecção da bactéria foi realizada através de PCRs diagnósticas, utilizando-se o gene 16S rDNA. A infecção pelo simbionte foi registrada pela primeira vez em Atlantoscia floridana e Burmoniscus meeusei. As linhagens de Wolbachia que infectam as espécies nativas de isópodos terrestres, ao contrário das introduzidas, são muito diversas e não se agrupam dentro do Oniclado. Já as sequências presentes em B. meeusei não são relacionadas a nenhuma outra linhagem presente em crustáceos...

First record of Wolbachia in South American terrestrial isopods : prevalence and diversity in two species of Balloniscus (Crustacea, Oniscidea)

Almerão, Maurício Pereira; Fagundes, Nelson Jurandi Rosa; Araujo, Paula Beatriz de; Verne, Sébastien; Grandjean, Frédéric; Bouchon, Didier; Araujo, Aldo Mellender de
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
37.6%
Wolbachia are endosymbiotic bacteria that commonly infect arthropods, inducing certain phenotypes in their hosts. So far, no endemic South American species of terrestrial isopods have been investigated for Wolbachia infection. In this work, populations from two species of Balloniscus (B. sellowii and B. glaber) were studied through a diagnostic PCR assay. Fifteen new Wolbachia 16S rDNA sequences were detected. Wolbachia found in both species were generally specific to one population, and five populations hosted two different Wolbachia 16S rDNA sequences. Prevalence was higher in B. glaber than in B. sellowii, but uninfected populations could be found in both species. Wolbachia strains from B. sellowii had a higher genetic variation than those isolated from B. glaber. AMOVA analyses showed that most of the genetic variance was distributed among populations of each species rather than between species, and the phylogenetic analysis suggested that Wolbachia strains from Balloniscus cluster within Supergroup B, but do not form a single monophyletic clade, suggesting multiple infections for this group. Our results highlight the importance of studying Wolbachia prevalence and genetic diversity in Neotropical species and suggest that South American arthropods may harbor a great number of diverse strains...

Presence and distribution of the endosymbiont Wolbachia among Solenopsis spp. (Hymenoptera: Formicidae) from Brazil and its evolutionary history

Martins, Cíntia; Souza, Rodrigo Fernando; Bueno, Odair Correa
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 287-296
ENG
Relevância na Pesquisa
37.44%
Wolbachia are intracellular bacteria that commonly infect arthropods. Its prevalence among ants of the genus Solenopsis is high. In the present study, the presence and distribution of these endosymbionts was examined among populations of Solenopsis spp. from Brazil. A phylogenetic analysis based on the wsp gene was conducted to infer the evolutionary history of Wolbachia infections within the populations surveyed. A high frequency of Wolbachia bacteria was observed among the genus Solenopsis, 51% of the colonies examined were infected. Incidence was higher in populations from southern Brazil. However, little genetic variability was found among different Wolbachia strains within supergroups A and B. Our findings also suggest that horizontal transmission events can occur through the social parasite S. daguerrei. © 2012 Elsevier Inc..

Identificação da bactéria endossimbionte Wolbachia em populações de moscas-das-frutas do complexo Anastrepha fraterculus (Diptera: Tephritidae)

Marcon, Helena Sanches
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 110 f.
POR
Relevância na Pesquisa
37.68%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Pós-graduação em Ciências Biológicas (Genética) - IBB; Wolbachia é uma bactéria endossimbionte comumente encontrada nos tecidos reprodutores de invertebrados, sendo herdada vertical e horizontalmente. Esta bactéria é desencadeadora de inúmeras alterações reprodutivas, dentre elas a incompatibilidade citoplasmática. Bactéria Wolbachia apresenta oito diferentes tipos de genoma, identificados de A a H. Dentre os hospedeiros da Wolbachia estão as moscas-das-frutas do gênero Anastrepha, que são um importante inseto-praga causador de inúmeras perdas na fruticultura de vários países na América. Neste estudo, foram utilizados os primers 16S rDNA, ftsZ e wsp na detecção da Wolbachia e identificação do supergrupo em três populações de Anastrepha do complexo fraterculus, de diferentes regiões do estado de São Paulo. Em todas as amostras de moscas foi detectada a presença da Wolbachia do supergrupo A, através da utilização dos primers 16S rDNA e wsp, visto que o ftsZ apresentou baixa sensibilidade na detecção desta bactéria em Anastrepha. Comparações das sequências do gene wsp dos 62 indivíduos no Genebank possibilitaram a identificação de duas linhagens de Wolbachia...

Produtividade em espécies de Drosophila do subgrupo saltans (grupo saltans, subgênero Sophophora): efeitos da infecção por Wolbachia em linhagens normais e introgredidas

Patarro, Thais de França
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Tese de Doutorado Formato: 76 f. : il. color., mapas, estampas
POR
Relevância na Pesquisa
37.56%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Pós-graduação em Genética - IBILCE; Reproductive isolation mechanisms are agents that prevent or decrease the exchange of genes between species or populations of the same species that are in process of speciation. These mechanisms are comprised of a series of processes operating at different levels of reproduction, ranging from pre-zygotic to post-zygotic barriers. In recent decades, studies have indicated that the absence of progeny can also be promoted by interactions of symbiont microorganisms and their hosts. Presently, the most known endosymbionts capable of interact with the insects, interfering in the reproductive process, are the alphaproteobacteria of the genus Wolbachia. In the present study, we investigated the Wolbachia effects on reproduction, focusing the parameter productivity (number of progeny) in crosses involving four strains of Drosophila saltans and D. prosaltans (close species belonging to the saltans group, Sophophora subgenus) and two introgressed strains started with F1 hybrids of these two species. Preliminary tests for screening Wolbachia showed that each of the six strains was infected with one strain of the symbiont. The results on productivity were obtained from intra and intercrosses of the strains in the conditions infected or uninfected. The elimination of Wolbachia was performed by treatment of the strains with the antibiotics tetracycline. The main mechanism resulting from the interaction symbiont-host described in the literature is called cytoplasmatic incompatibility (CI) and occurs in the intercrosses of uninfected females with infected males. It is considered that...

Natural occurrence of Wolbachia-infected and uninfected Trichogramma species in tomato fields in Portugal.

Gonçalves, Catarina I.; Huigens, Martinus E.; Verbaarschot, Patrick; Duarte, Sónia; Mexia, António; Tavares, João
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2006 ENG
Relevância na Pesquisa
37.56%
Copyright © 2005 Elsevier Inc. All rights reserved.; Minute egg parasitoids of the genus Trichogramma (Hymenoptera; Trichogrammatidae) are promising candidates for biological control of lepidopteran pests in tomato in Portugal. This certainly applies to native Trichogramma strains that have thelytokous reproduction, i.e., produce only daughters. In Trichogramma wasps, thelytoky is mostly induced by the intracellular bacterium Wolbachia. In this study, we carried out a field survey of native Trichogramma species in four locations in Ribatejo, the main processing tomato region of Portugal, and determined the prevalence of Wolbachia in those species. Five Trichogramma species were found to emerge from lepidopteran eggs collected in the field, namely Trichogramma bourarache, Trichogramma cordubensis, Trichogramma evanescens, Trichogramma pintoi, and Trichogramma turkestanica. T. evanescens and T. pintoi were by far the dominating species representing, respectively, 64.9 and 26.4% of the trichogrammatids collected. Total natural parasitism rates of the collected lepidopteran eggs by Trichogramma wasps ranged from 28.2 to 64.6%. Three Trichogramma species were found to be infected with Wolbachia, namely T. cordubensis, T. evanescens, and T. turkestanica. All the wasp broods belonging to T. cordubensis were infected...

Detection and characterization of Wolbachia infections in natural populations of aphids: is the hidden diversity fully unraveled?

Augustinos, Antonis A.; Santos-Garcia, Diego; Dionyssopoulou, Eva; Moreira, Marta; Papapanagiotou, Aristeidis; Scarvelakis, Marios; Doudoumis, Vangelis; Ramos, Silvia; Aguiar, António F.; Borges, Paulo A. V.; Khadem, Manhaz; Latorre, Amparo; Tsiamis, Geo
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em /12/2011 ENG
Relevância na Pesquisa
37.49%
Copyright © 2011 Augustinos et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.; Aphids are a serious threat to agriculture, despite being a rather small group of insects. The about 4,000 species worldwide engage in highly interesting and complex relationships with their microbial fauna. One of the key symbionts in arthropods is Wolbachia, an a-Proteobacterium implicated in many important biological processes and believed to be a potential tool for biological control. Aphids were thought not to harbour Wolbachia; however, current data suggest that its presence in aphids has been missed, probably due to the low titre of the infection and/or to the high divergence of the Wolbachia strains of aphids. The goal of the present study is to map the Wolbachia infection status of natural aphids populations, along with the characterization of the detected Wolbachia strains. Out of 425 samples from Spain, Portugal, Greece, Israel and Iran, 37 were found to be infected. Our results, based mainly on 16S rRNA gene sequencing, indicate the presence of two new Wolbachia supergroups prevailing in aphids...

Detection of Wolbachia pipientis, including a new strain containing the wsp gene, in two sister species of Paraphlebotomus sandflies, potential vectors of zoonotic cutaneous leishmaniasis

Parvizi,Parviz; Bordbar,Ali; Najafzadeh,Narmin
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
Relevância na Pesquisa
37.49%
Individual, naturally occurring Phlebotomus mongolensis and Phlebotomus caucasicus from Iran were screened for infections with the maternally inherited intracellular Rickettsia-like bacterium Wolbachia pipientis via targeting a major surface protein gene (wsp). The main objective of this study was to determine if W. pipientis could be detected in these species. The sandflies were screened using polymerase chain reaction to amplify a fragment of the Wolbachia surface protein gene. The obtained sequences were edited and aligned with database sequences to identify W. pipientis haplotypes. Two strains of Wolbachia were found. Strain Turk 54 (accession EU780683) is widespread and has previously been reported in Phlebotomus papatasi and other insects. Strain Turk 07 (accession KC576916) is a novel strain, found for first time in the two sister species. A-group strains of W. pipientis occur throughout much of the habitat of these sandflies. It is possible that Wolbachia is transferred via horizontal transmission. Horizontal transfer could shed light on sandfly control because Wolbachia is believed to drive a deleterious gene into sandflies that reduces their natural population density. With regard to our findings in this study, we can conclude that one species of sandfly can be infected with different Wolbachia strains and that different species of sandflies can be infected with a common strain.

First record of Wolbachia in South American terrestrial isopods: prevalence and diversity in two species of Balloniscus (Crustacea, Oniscidea)

Almerão,Mauricio Pereira; Fagundes,Nelson Jurandi Rosa; Araújo,Paula Beatriz de; Verne,Sébastien; Grandjean,Frédéric; Bouchon,Didier; Araújo,Aldo Mellender
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
37.58%
Wolbachia are endosymbiotic bacteria that commonly infect arthropods, inducing certain phenotypes in their hosts. So far, no endemic South American species of terrestrial isopods have been investigated for Wolbachia infection. In this work, populations from two species of Balloniscus (B. sellowii and B. glaber) were studied through a diagnostic PCR assay. Fifteen new Wolbachia 16S rDNA sequences were detected. Wolbachia found in both species were generally specific to one population, and five populations hosted two different Wolbachia 16S rDNA sequences. Prevalence was higher in B. glaber than in B. sellowii, but uninfected populations could be found in both species. Wolbachia strains from B. sellowii had a higher genetic variation than those isolated from B. glaber. AMOVA analyses showed that most of the genetic variance was distributed among populations of each species rather than between species, and the phylogenetic analysis suggested that Wolbachia strains from Balloniscus cluster within Supergroup B, but do not form a single monophyletic clade, suggesting multiple infections for this group. Our results highlight the importance of studying Wolbachia prevalence and genetic diversity in Neotropical species and suggest that South American arthropods may harbor a great number of diverse strains...

Detection and characterization of Wolbachia infection in silkworm

Zha,Xingfu; Zhang,Wenji; Zhou,Chunyan; Zhang,Liying; Xiang,Zhonghuai; Xia,Qingyou
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
Relevância na Pesquisa
37.53%
Wolbachia naturally infects a wide variety of arthropods, where it plays important roles in host reproduction. It was previously reported that Wolbachia did not infect silkworm. By means of PCR and sequencing we found in this study that Wolbachia is indeed present in silkworm. Phylogenetic analysis indicates that Wolbachia infection in silkworm may have occurred via transfer from parasitic wasps. Furthermore, Southern blotting results suggest a lateral transfer of the wsp gene into the genomes of some wild silkworms. By antibiotic treatments, we found that tetracycline and ciprofloxacin can eliminate Wolbachia in the silkworm and Wolbachia is important to ovary development of silkworm. These results provide clues towards a more comprehensive understanding of the interaction between Wolbachia and silkworm and possibly other lepidopteran insects.

Wolbachia and cytoplasmic-nuclear conflict in Drosophila melanogaster

Karmally, Jennifer
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
37.53%
The cytoplasm and the nucleus of a cell are likely to be adapted to one another. Disrupting this coadaptation can cause conflict between cytoplasmic and nuclear elements. Experimentally evolved fast developing (ACO) and slow developing (CO) lines of Drosophila melanogaster were crossed such that the nucleus of one line was embedded within the cytoplasm of the other (CS treatment). While cyto-nuclear conflict was observed, a Wolbachia infection was detected. Wolbachia is an endosymbiont that favours female function over male function, which can lead to cytoplasmic interference in D melanogaster. Cytoplasmic inteference is a form of cytoplasmic nuclear conflict and the effects are indistinguishable from mitochondrial nuclear conflict. To test for the effects of Wolbachia on cytoplasmic-nuclear interactions, post-copulatory success for populations cured of Wolbachia with tetracycline, and populations infected with Wolbachia were assessed in a sperm competition experiment. Curing the Wolbachia infection had no influence on sperm competitive ability. This suggests that Wolbachia had no effect on previous observations of cyto-nuclear conflict. Populations with a CO nucleus had higher sperm competitive ability than populations with an ACO nucleus across all analyses and populations with CO cytoplasm had a higher sperm competitive ability than populations with ACO cytoplasm...

PROTEOMIC ANALYSIS OF WOLBACHIA SYMBIOSIS WITHIN THE DROSOPHILA OVARY

Perez, Ricardo
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
37.58%
Wolbachia pipientis are bacterial endosymbionts carried by millions of invertebrate species, including ~40% of insect species and some filarial nematodes. In insects, basic Wolbachia research has potential applications in controlling vector borne disease. Conversely, Wolbachia of filarial nematodes are causative agents of neglected tropical diseases such as lymphatic filariasis and African river blindness. However, remarkably little is known about how Wolbachia interact with their hosts at the molecular level. Understanding this is important to inform the basis for symbiosis and help prevent human disease. I used a high-throughput proteomics approach to study how Drosophila host cells are modified by Wolbachia infection. This analysis identified 23 Drosophila proteins that significantly changed in amount as a result of Wolbachia infection. A subset of differentially abundant host proteins were consistent with Wolbachia-associated phenotypes reported previously. This study also provides the first ever discovery-based evidence for a Wolbachia-associated change in maternal germline histone loads, which has possible implications in Rescue of a common Wolbachia-induced reproductive manipulation known as Cytoplasmic Incompatibility.

Mutualism Breakdown by Amplification of Wolbachia Genes

Chrostek, Ewa; Teixeira, Luis
Fonte: PLOS Publicador: PLOS
Tipo: Artigo de Revista Científica
Publicado em 10/02/2015 ENG
Relevância na Pesquisa
37.56%
Most insect species are associated with vertically transmitted endosymbionts. Because of the mode of transmission, the fitness of these symbionts is dependent on the fitness of the hosts. Therefore, these endosymbionts need to control their proliferation in order to minimize their cost for the host. The genetic bases and mechanisms of this regulation remain largely undetermined. The maternally inherited bacteria of the genus Wolbachia are the most common endosymbionts of insects, providing some of them with fitness benefits. In Drosophila melanogaster, Wolbachia wMelPop is a unique virulent variant that proliferates massively in the hosts and shortens their lifespan. The genetic bases of wMelPop virulence are unknown, and their identification would allow a better understanding of how Wolbachia levels are regulated. Here we show that amplification of a region containing eight Wolbachia genes, called Octomom, is responsible for wMelPop virulence. Using Drosophila lines selected for carrying Wolbachia with different Octomom copy numbers, we demonstrate that the number of Octomom copies determines Wolbachia titers and the strength of the lethal phenotype. Octomom amplification is unstable, and reversion of copy number to one reverts all the phenotypes. Our results provide a link between genotype and phenotype in Wolbachia and identify a genomic region regulating Wolbachia proliferation. We also prove that these bacteria can evolve rapidly. Rapid evolution by changes in gene copy number may be common in endosymbionts with a high number of mobile elements and other repeated regions. Understanding wMelPop pathogenicity and variability also allows researchers to better control and predict the outcome of releasing mosquitoes transinfected with this variant to block human vector-borne diseases. Our results show that transition from a mutualist to a pathogen may occur because of a single genomic change in the endosymbiont. This implies that there must be constant selection on endosymbionts to control their densities.; FCT PhD fellowship: (SFRH/BD/51625/2011).

The Impact of Host Diet on Wolbachia Titer in Drosophila

Serbus, Laura R.; White, Pamela M.; Silva, Jessica Pintado; Rabe, Amanda; Teixeira, Luis; Albertson, Roger; Sullivan, William
Fonte: PLOS Publicador: PLOS
Tipo: Artigo de Revista Científica
Publicado em 31/03/2015 ENG
Relevância na Pesquisa
37.56%
While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.; Florida International University, National Institutes of Health...

Symbionts commonly provide broad spectrum resistance to viruses in insects: a comparative analysis of Wolbachia strains

Martinez, Julien; Longdon, Ben; Bauer, Simone; Chan, Yuk-Sang; Miller, Wolfgang J; Bourtzis, Kostas; Teixeira, Luis; Jiggins, Francis M
Fonte: PLOS Publicador: PLOS
Tipo: Artigo de Revista Científica
Publicado em 18/09/2014 ENG
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37.56%
In the last decade, bacterial symbionts have been shown to play an important role in protecting hosts against pathogens. Wolbachia, a widespread symbiont in arthropods, can protect Drosophila and mosquito species against viral infections. We have investigated antiviral protection in 19 Wolbachia strains originating from 16 Drosophila species after transfer into the same genotype of Drosophila simulans. We found that approximately half of the strains protected against two RNA viruses. Given that 40% of terrestrial arthropod species are estimated to harbour Wolbachia, as many as a fifth of all arthropods species may benefit from Wolbachia-mediated protection. The level of protection against two distantly related RNA viruses--DCV and FHV--was strongly genetically correlated, which suggests that there is a single mechanism of protection with broad specificity. Furthermore, Wolbachia is making flies resistant to viruses, as increases in survival can be largely explained by reductions in viral titer. Variation in the level of antiviral protection provided by different Wolbachia strains is strongly genetically correlated to the density of the bacteria strains in host tissues. We found no support for two previously proposed mechanisms of Wolbachia-mediated protection--activation of the immune system and upregulation of the methyltransferase Dnmt2. The large variation in Wolbachia's antiviral properties highlights the need to carefully select Wolbachia strains introduced into mosquito populations to prevent the transmission of arboviruses.; Wellcome Trust grant WT094664MA...

Dynamics of Wolbachia pipientis gene expression across the Drosophila melanogaster life cycle

Florence Gutzwiller; Catarina R. Carmo; Danny E. Miller; Danny W. Rice; Irene L. Newton; R. Scott Hawley; Luis Teixeira; Casey M. Bergman
Fonte: Genetics Society of America Publicador: Genetics Society of America
Tipo: Artigo de Revista Científica
Publicado em 23/10/2015 ENG
Relevância na Pesquisa
37.56%
Symbiotic interactions between microbes and their multicellular hosts have manifold impacts on molecular, cellular and organismal biology. To identify candidate bacterial genes involved in maintaining endosymbiotic associations with insect hosts, we analyzed genome-wide patterns of gene expression in the alpha-proteobacteria Wolbachia pipientis across the life cycle of Drosophila melanogaster using public data from the modENCODE project that was generated in a Wolbachia-infected version of the ISO1 reference strain. We find that the majority of Wolbachia genes are expressed at detectable levels in D. melanogaster across the entire life cycle, but that only 7.8% of 1195 Wolbachia genes exhibit robust stage- or sex-specific expression differences when studied in the "holo-organism" context. Wolbachia genes that are differentially expressed during development are typically up-regulated after D. melanogaster embryogenesis, and include many bacterial membrane, secretion system and ankyrin-repeat containing proteins. Sex-biased genes are often organised as small operons of uncharacterised genes and are mainly up-regulated in adult males D. melanogaster in an age-dependent manner suggesting a potential role in cytoplasmic incompatibility. Our results indicate that large changes in Wolbachia gene expression across the Drosophila life-cycle are relatively rare when assayed across all host tissues...