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1.
Viruses ; 13(6)2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199957

RESUMO

Viruses, and in particular the deformed wing virus (DWV), are considered as one of the main antagonists of honey bee health. The 'suppressed in ovo virus infection' trait (SOV) described for the first time that control of a virus infection can be achieved from genetically inherited traits and that the virus state of the eggs is indicative for this. This research aims to explore the effect of the SOV trait on DWV infections in queens descending from both SOV-positive (QDS+) and SOV-negative (QDS-) queens. Twenty QDS+ and QDS- were reared from each time four queens in the same starter-finisher colony. From each queen the head, thorax, ovaries, spermatheca, guts and eviscerated abdomen were dissected and screened for the presence of the DWV-A and DWV-B genotype using qRT-PCR. Queens descending from SOV-positive queens showed significant lower infection loads for DWV-A and DWV-B as well as a lower number of infected tissues for DWV-A. Surprisingly, differences were less expressed in the reproductive tissues, the ovaries and spermatheca. These results confirm that selection on the SOV trait is associated with increased virus resistance across viral genotypes and that this selection drives DWV towards an increased tissue specificity for the reproductive tissues. Further research is needed to explore the mechanisms underlying the interaction between the antiviral response and DWV.


Assuntos
Doenças dos Animais/virologia , Abelhas/virologia , Cruzamento , Resistência à Doença/genética , Interações Hospedeiro-Patógeno/genética , Infecções por Vírus de RNA/veterinária , Vírus de RNA/fisiologia , Doenças dos Animais/genética , Animais , Carga Viral
2.
BMC Vet Res ; 17(1): 179, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931072

RESUMO

BACKGROUND: The varroa mite is one of the main causes of honey bee mortality. An important mechanism by which honey bees increase their resistance against this mite is the expression of suppressed mite reproduction. This trait describes the physiological inability of mites to produce viable offspring and was found associated with eight genomic variants in previous research. RESULTS: This paper presents the development and validation of high-throughput qPCR assays with dual-labeled probes for discriminating these eight single-nucleotide variants. Amplicon sequences used for assay validation revealed additional variants in the primer/probe binding sites in four out of the eight assays. As for two of these the additional variants interfered with the genotyping outcome supplementary primers and/or probes were developed. Inclusion of these primers and probes in the assay mixes allowed for the correct genotyping of all eight variants of interest within our bee population. CONCLUSION: These outcomes underline the importance of checking for interfering variants in designing qPCR assays. Ultimately, the availability of this assay allows genotyping for the suppressed mite reproduction trait and paves the way for marker assisted selection in breeding programs.


Assuntos
Abelhas/genética , Abelhas/parasitologia , Interações Hospedeiro-Parasita/genética , Animais , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Reação em Cadeia da Polimerase em Tempo Real , Reprodução/fisiologia , Varroidae
3.
Viruses ; 12(11)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33121140

RESUMO

Metagenomics studies have accelerated the discovery of novel or divergent viruses of the honey bee. However, most of these studies predominantly focused on RNA viruses, and many suffer from the relatively low abundance of viral nucleic acids in the samples (i.e., compared to that of the host). Here, we explored the virome of the Ethiopian honey bee, Apis mellifera simensis, using an unbiased metagenomic approach in which the next-generation sequencing step was preceded by an enrichment protocol for viral particles. Our study revealed five well-known bee viruses and 25 atypical virus species, most of which have never been found in A. mellifera before. The viruses belong to Iflaviridae, Dicistroviridae, Secoviridae, Partitiviridae, Parvoviridae, Potyviridae, and taxonomically unclassified families. Fifteen of these atypical viruses were most likely plant-specific, and the remaining ten were presumed to be insect-specific. Apis mellifera filamentous virus (AmFV) was found in one sampling site out of 10. Two samples contained high read counts of a virus similar to Diatraea saccharales densovirus (DsDNV), which is a virus that causes high mortality in the sugarcane borer. AmFV and the DsDNV-like virus were the only DNA viruses found. Three viruses that primarily infect Drosophila spp. were also discovered: La Jolla virus (LJV), Kilifi virus (KiV), and Thika virus. Our study suggests that phoretic varroa mites are involved in the transmission of LJV and KiV and that both viruses replicate in mites and adult bees. We also found an overwhelming dominance of the deformed wing virus type B variant, which fits well with the apparently harmless infestation by Varroa destructor. It was suggested that Ethiopian bees have developed tolerance against virus infections as the result of natural selection.


Assuntos
Abelhas/virologia , Metagenômica/métodos , Virologia/métodos , Viroses/veterinária , Vírus/classificação , Animais , Etiópia , Sequenciamento de Nucleotídeos em Larga Escala , Metagenoma , Filogenia , Varroidae/virologia , Viroma , Viroses/transmissão , Vírus/isolamento & purificação
4.
Sci Rep ; 10(1): 14310, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868870

RESUMO

Honey bees are under pressure due to abnormal high colony death rates, especially during the winter. The infestation by the Varroa destructor mite and the viruses that this ectoparasite transmits are generally considered as the bees' most important biological threats. Almost all efforts to remedy this dual infection have so far focused on the control of the Varroa mite alone and not on the viruses it transmits. In the present study, the sanitary control of breeding queens was conducted on eggs taken from drone brood for 4 consecutive years (2015-2018). The screening was performed on the sideline of an ongoing breeding program, which allowed us to estimate the heritabilities of the virus status of the eggs. We used the term 'suppressed in ovo virus infection' (SOV) for this novel trait and found moderate heritabilities for the presence of several viruses simultaneously and for the presence of single viral species. Colonies that expressed the SOV trait seemed to be more resilient to virus infections as a whole with fewer and less severe Deformed wing virus infections in most developmental stages, especially in the male caste. The implementation of this novel trait into breeding programs is recommended.


Assuntos
Abelhas/genética , Abelhas/imunologia , Animais , Abelhas/parasitologia , Abelhas/virologia , Resistência à Doença/genética , Feminino , Masculino , Característica Quantitativa Herdável , Varroidae/virologia
5.
Sci Rep ; 9(1): 7794, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31127129

RESUMO

Host-parasite co-evolution history is lacking when parasites switch to novel hosts. This was the case for Western honey bees (Apis mellifera) when the ectoparasitic mite, Varroa destructor, switched hosts from Eastern honey bees (Apis cerana). This mite has since become the most severe biological threat to A. mellifera worldwide. However, some A. mellifera populations are known to survive infestations, largely by suppressing mite population growth. One known mechanism is suppressed mite reproduction (SMR), but the underlying genetics are poorly understood. Here, we take advantage of haploid drones, originating from one queen from the Netherlands that developed Varroa-resistance, whole exome sequencing and elastic-net regression to identify genetic variants associated with SMR in resistant honeybees. An eight variants model predicted 88% of the phenotypes correctly and identified six risk and two protective variants. Reproducing and non-reproducing mites could not be distinguished using DNA microsatellites, which is in agreement with the hypothesis that it is not the parasite but the host that adapted itself. Our results suggest that the brood pheromone-dependent mite oogenesis is disrupted in resistant hosts. The identified genetic markers have a considerable potential to contribute to a sustainable global apiculture.


Assuntos
Abelhas/parasitologia , Infestações por Ácaros/veterinária , Varroidae/fisiologia , Animais , Abelhas/genética , Abelhas/fisiologia , Feminino , Frequência do Gene , Variação Genética , Interações Hospedeiro-Parasita , Masculino , Infestações por Ácaros/genética , Infestações por Ácaros/parasitologia , Reprodução , Varroidae/genética , Sequenciamento Completo do Exoma
6.
Toxicon ; 150: 198-206, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29842867

RESUMO

Honeybee (Apis mellifera) venom (HBV) represents an ideal model to study the role of particular venom components in allergic reactions in sensitized individuals as well as in the eusociality of Hymenoptera species. The aim of this study was to further characterize the HBV components C1q-like protein (C1q) and PDGF/VEGF-like factor 1 (PVF1). C1q and PVF1 were produced as recombinant proteins in insect cells. Their allergenic properties were examined by determining the level of specific IgE antibodies in the sera of HBV-allergic patients (n = 26) as well as by their capacity to activate patients' basophils (n = 11). Moreover, the transcript heterogeneity of PVF1 was analyzed. It could be demonstrated that at least three PVF1 variants are present in the venom gland, which all result from alternative splicing of one transcript. Additionally, recombinant C1q and PVF1 from Spodoptera frugiperda insect cells exhibited specific IgE reactivity with approximately 38.5% of sera of HBV-allergic patients. Interestingly, both proteins were unable to activate basophils of the patients, questioning their role in the context of clinically relevant sensitization. Recombinant C1q and PVF1 can build the basis for a deeper understanding of the molecular mechanisms of Hymenoptera venoms. Moreover, the conflicting results between IgE sensitization and lack of basophil activation, might in the future contribute to the identification of factors that determine the allergenic potential of proteins.


Assuntos
Venenos de Abelha/química , Abelhas/fisiologia , Hipersensibilidade , Proteínas de Insetos/química , Proteínas de Insetos/toxicidade , Alérgenos/química , Alérgenos/toxicidade , Animais , Baculoviridae , Clonagem Molecular , Regulação da Expressão Gênica , Humanos , Mordeduras e Picadas de Insetos , Células Sf9
7.
Eur J Protistol ; 61(Pt A): 13-19, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28826077

RESUMO

The microsporidium Nosema neumanni n. sp., a new parasite of the honeybee Apis mellifera is described based on its ultra-structural and molecular characteristics. Structures resembling microsporidian spores were found by microscopic examination of honeybees from Uganda. Molecular confirmation failed when PCR primers specific for Nosema apis and Nosema ceranae were used, but was successful with primers covering the whole family of Nosematidae. We performed transmission electron microscopy and found typical microsporidian spores which were smaller (length: 2.36±0.14µm and width: 1.78±0.06µm; n=6) and had fewer polar filament coils (10-12) when compared to those of known species infecting honeybees. The entire 16S SSU rRNA region was amplified, cloned and sequenced and was found to be unique with the highest resemblance (97% identity) to N. apis. The incidence of N. neumanni n. sp. in Ugandan honeybees was found to be much higher than of the two other Nosema species.


Assuntos
Abelhas/parasitologia , Nosema/classificação , Animais , Microscopia Eletrônica de Transmissão , Nosema/genética , Nosema/ultraestrutura , RNA Ribossômico 16S/genética , Especificidade da Espécie , Uganda
8.
Proc Biol Sci ; 284(1848)2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28148747

RESUMO

Several studies have suggested that covert stressors can contribute to bee colony declines. Here we provide a novel case study and show using radiofrequency identification tracking technology that covert deformed wing virus (DWV) infections in adult honeybee workers seriously impact long-term foraging and survival under natural foraging conditions. In particular, our experiments show that adult workers injected with low doses of DWV experienced increased mortality rates, that DWV caused workers to start foraging at a premature age, and that the virus reduced the workers' total activity span as foragers. Altogether, these results demonstrate that covert DWV infections have strongly deleterious effects on honeybee foraging and survival. These results are consistent with previous studies that suggested DWV to be an important contributor to the ongoing bee declines in Europe and the USA. Overall, our study underlines the strong impact that covert pathogen infections can have on individual and group-level performance in bees.


Assuntos
Comportamento Apetitivo , Abelhas/virologia , Vírus de Insetos/patogenicidade , Asas de Animais/virologia , Animais
9.
PLoS One ; 12(2): e0171529, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28182641

RESUMO

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period of 40 days. Next to these variables, a laboratory-field comparison was conducted. The influence of the chronic exposure on gene expression levels was determined using an in-house developed microarray targeting different immunity-related and detoxification genes to determine stress-related gene expression changes. Increased levels of the detoxification genes encoding, CYP9Q3 and CYT P450, were detected in imidacloprid-exposed honey bees. The different context-dependent effects of imidacloprid exposure on honey bees were confirmed physiologically by decreased hypopharyngeal gland sizes. Honey bees exposed to imidacloprid in laboratory cages showed a general immunosuppression and no detoxification mechanisms were triggered significantly, while honey bees in-field showed a resilient response with an immune stimulation at later time points. However, the treated colonies had a brood and population decline tendency after the first brood cycle in the field. In conclusion, this study highlighted the different context-dependent effects of imidacloprid exposure on the honey bee response. These findings warn for possible pitfalls concerning the generalization of results based on specific experiments with short exposure times. The increased levels of CYT P450 and CYP9Q3 combined with an immune response reaction can be used as markers for bees which are exposed to pesticides in the field.


Assuntos
Abelhas/efeitos dos fármacos , Imidazóis/toxicidade , Proteínas de Insetos/genética , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Estresse Fisiológico , Animais , Abelhas/genética , Abelhas/crescimento & desenvolvimento , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Proteínas de Insetos/metabolismo , Inseticidas/administração & dosagem , Inseticidas/farmacologia , Neonicotinoides , Nitrocompostos/administração & dosagem , Nitrocompostos/farmacologia
10.
PLoS One ; 11(12): e0168456, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28006002

RESUMO

The diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, Apis mellifera. Using a deliberate RNA shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, Bombus terrestris and Bombus pascuorum, and two solitary bee hosts, Osmia cornuta and Andrena vaga. Ion Torrent semiconductor sequencing generated approximately 3.8 million high quality reads. The most significant eukaryote associations were two protozoan, Apicystis bombi and Crithidia bombi, and one nematode parasite Sphaerularia bombi in bumble bees. The trypanosome protozoan C. bombi was also found in the solitary bee O. cornuta. Next to the identification of three honey bee viruses Black queen cell virus, Sacbrood virus and Varroa destructor virus-1 and four plant viruses, we describe two novel RNA viruses Scaldis River bee virus (SRBV) and Ganda bee virus (GABV) based on their partial genomic sequences. The novel viruses belong to the class of negative-sense RNA viruses, SRBV is related to the order Mononegavirales whereas GABV is related to the family Bunyaviridae. The potential biological role of both viruses in bees is discussed in the context of recent advances in the field of arthropod viruses. Further, fragmentary sequence evidence for other undescribed viruses is presented, among which a nudivirus in O. cornuta and an unclassified virus related to Chronic bee paralysis virus in B. terrestris. Our findings extend the current knowledge of wild bee parasites in general and addsto the growing evidence of unexplored arthropod viruses in valuable insects.


Assuntos
Abelhas/genética , Eucariotos/genética , Metagenômica , Parasitos/genética , Vírus de RNA/genética , Animais , Abelhas/classificação , Abelhas/parasitologia , Abelhas/virologia
11.
Microb Biotechnol ; 9(6): 772-781, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27365124

RESUMO

American Foulbrood, caused by Paenibacillus larvae, is the most severe bacterial disease of honey bees (Apis mellifera). To perform genotyping of P. larvae in an epidemiological context, there is a need of a fast and cheap method with a high resolution. Here, we propose Multiple Locus Variable number of tandem repeat Analysis (MLVA). MLVA has been used for typing a collection of 209 P. larvae strains from which 23 different MLVA types could be identified. Moreover, the developed methodology not only permits the identification of the four Enterobacterial Repetitive Intergenic Consensus (ERIC) genotypes, but allows also a discriminatory subdivision of the most dominant ERIC type I and ERIC type II genotypes. A biogeographical study has been conducted showing a significant correlation between MLVA genotype and the geographical region where it was isolated.


Assuntos
Técnicas de Genotipagem/métodos , Repetições Minissatélites , Tipagem Molecular/métodos , Paenibacillus larvae/classificação , Paenibacillus larvae/genética , Paenibacillus larvae/isolamento & purificação , Filogeografia
12.
Exp Appl Acarol ; 68(4): 497-508, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26801158

RESUMO

Varroa mites are ecto-parasites of honeybees and are a threat to the beekeeping industry. We identified the haplotype of Varroa mites and evaluated potential factors that influence their prevalence and infestation levels in the eastern and western highland agro-ecological zones of Uganda. This was done by collecting samples of adult worker bees between December 2014 and September 2015 in two sampling moments. Samples of bees were screened for Varroa using the ethanol wash method and the mites were identified by molecular techniques. All DNA sequences obtained from sampled mite populations in the two zones were 100 % identical to the Korean Haplotype (AF106899). Mean mite prevalence in the apiaries was 40 and 53 % for the western and eastern zones, respectively, during the first sampling. Over the second sampling, mean mite prevalence increased considerably in the western (59 %) but not in the eastern (51 %) zone. Factors that were associated with Varroa mite infestation levels include altitude, nature of apiary slope and apiary management practices during the first sampling. Our results further showed that Varroa mites were spreading from lower to higher elevations. Feral colonies were also infested with Varroa mites at infestation levels not significantly different from those in managed colonies. Colony productivity and strength were not correlated to mite infestation levels. We recommend a long-term Varroa mite monitoring strategy in areas of varying landscape and land use factors for a clear understanding of possible changes in mite infestation levels among African honeybees for informed decision making.


Assuntos
Abelhas/parasitologia , Varroidae/fisiologia , Animais , Criação de Abelhas , Prevalência , Uganda
13.
J Invertebr Pathol ; 130: 21-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26146231

RESUMO

Trypanosomatids infecting honey bees have been poorly studied with molecular methods until recently. After the description of Crithidia mellificae (Langridge and McGhee, 1967) it took about forty years until molecular data for honey bee trypanosomatids became available and were used to identify and describe a new trypanosomatid species from honey bees, Lotmaria passim (Evans and Schwarz, 2014). However, an easy method to distinguish them without sequencing is not yet available. Research on the related bumble bee parasites Crithidia bombi and Crithidia expoeki revealed a fragment length polymorphism in the internal transcribed spacer 1 (ITS1), which enabled species discrimination. In search of fragment length polymorphisms for differential diagnostics in honey bee trypanosomatids, we studied honey bee trypanosomatid cell cultures of C. mellificae and L. passim. This research resulted in the identification of fragment length polymorphisms in ITS1 and ITS1-2 markers, which enabled us to develop a diagnostic method to differentiate both honey bee trypanosomatid species without the need for sequencing. However, the amplification success of the ITS1 marker depends probably on the trypanosomatid infection level. Further investigation confirmed that L. passim is the dominant species in Belgium, Japan and Switzerland. We found C. mellificae only rarely in Belgian honey bee samples, but not in honey bee samples from other countries. C. mellificae was also detected in mason bees (Osmia bicornis and Osmia cornuta) besides in honey bees. Further, the characterization and comparison of additional markers from L. passim strain SF (published as C. mellificae strain SF) and a Belgian honey bee sample revealed very low divergence in the 18S rRNA, ITS1-2, 28S rRNA and cytochrome b sequences. Nevertheless, a variable stretch was observed in the gp63 virulence factor.


Assuntos
Abelhas/parasitologia , Crithidia/parasitologia , Diagnóstico Diferencial , Trypanosomatina/parasitologia , Sequência de Aminoácidos , Animais , Genes de Protozoários , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
14.
BMC Vet Res ; 11: 61, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25889959

RESUMO

BACKGROUND: The Member States of European Union are encouraged to improve the general conditions for the production and marketing of apicultural products. In Belgium, programmes on the restocking of honey bee hives have run for many years. Overall, the success ratio of this queen breeding programme has been only around 50%. To tackle this low efficacy, we organized sanitary controls of the breeding queens in 2012 and 2014. RESULTS: We found a high quantity of viruses, with more than 75% of the egg samples being infected with at least one virus. The most abundant viruses were Deformed Wing Virus and Sacbrood Virus (≥40%), although Lake Sinai Virus and Acute Bee Paralysis Virus were also occasionally detected (between 10-30%). In addition, Aphid Lethal Paralysis Virus strain Brookings, Black Queen Cell Virus, Chronic Bee Paralysis Virus and Varroa destructor Macula-like Virus occurred at very low prevalences (≤5%). Remarkably, we found Apis mellifera carnica bees to be less infected with Deformed Wing Virus than Buckfast bees (p < 0.01), and also found them to have a lower average total number of infecting viruses (p < 0.001). This is a significant finding, given that Deformed Wing Virus has earlier been shown to be a contributory factor to winter mortality and Colony Collapse Disorder. Moreover, negative-strand detection of Sacbrood Virus in eggs was demonstrated for the first time. CONCLUSIONS: High pathogen loads were observed in this sanitary control program. We documented for the first time vertical transmission of some viruses, as well as significant differences between two honey bee races in being affected by Deformed Wing Virus. Nevertheless, we could not demonstrate a correlation between the presence of viruses and queen breeding efficacies.


Assuntos
Abelhas/virologia , Vírus de Insetos , Criação de Animais Domésticos/métodos , Animais , Bélgica , Colapso da Colônia/prevenção & controle , Colapso da Colônia/virologia , Transmissão Vertical de Doenças Infecciosas/veterinária , Vírus de Insetos/patogenicidade
15.
Virus Res ; 201: 67-72, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25725149

RESUMO

Honey bees (Apis mellifera) are susceptible to a wide range of pathogens, including a broad set of viruses. Recently, next-generation sequencing has expanded the list of viruses with, for instance, two strains of Lake Sinai Virus. Soon after its discovery in the USA, LSV was also discovered in other countries and in other hosts. In the present study, we assemble four almost complete LSV genomes, and show that there is remarkable sequence heterogeneity based on the Orf1, RNA-dependent RNA polymerase and capsid protein sequences in comparison to the previously identified LSV 1 and 2 strains. Phylogenetic analyses of LSV sequences obtained from single honey bee specimens further revealed that up to three distinctive clades could be present in a single bee. Such superinfections have not previously been identified for other honey bee viruses. In a search for the putative routes of LSV transmission, we were able to demonstrate the presence of LSV in pollen pellets and in Varroa destructor mites. However, negative-strand analyses demonstrated that the virus only actively replicates in honey bees and mason bees (Osmia cornuta) and not in Varroa mites.


Assuntos
Abelhas/virologia , Proteínas do Capsídeo/genética , Polimorfismo Genético , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , RNA Polimerase Dependente de RNA/genética , Animais , Bélgica , Análise por Conglomerados , Ácaros/virologia , Dados de Sequência Molecular , Filogenia , Pólen/virologia , Vírus de RNA/genética , Análise de Sequência de DNA , Homologia de Sequência
16.
Mol Immunol ; 63(2): 449-55, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25451974

RESUMO

Api m 10 has recently been established as novel major allergen that is recognized by more than 60% of honeybee venom (HBV) allergic patients. Previous studies suggest Api m 10 protein heterogeneity which may have implications for diagnosis and immunotherapy of HBV allergy. In the present study, RT-PCR revealed the expression of at least nine additional Api m 10 transcript isoforms by the venom glands. Two distinct mechanisms are responsible for the generation of these isoforms: while the previously known variant 2 is produced by an alternative splicing event, novel identified isoforms are intragenic chimeric transcripts. To the best of our knowledge, this is the first report of the identification of chimeric transcripts generated by the honeybee. By a retrospective proteomic analysis we found evidence for the presence of several of these isoforms in the venom proteome. Additionally, we analyzed IgE reactivity to different isoforms by protein array technology using sera from HBV allergic patients, which revealed that IgE recognition of Api m 10 is both isoform- and patient-specific. While it was previously demonstrated that the majority of HBV allergic patients display IgE reactivity to variant 2, our study also shows that some patients lacking IgE antibodies for variant 2 display IgE reactivity to two of the novel identified Api m 10 variants, i.e. variants 3 and 4.


Assuntos
Alérgenos/imunologia , Venenos de Abelha/imunologia , Abelhas/imunologia , Imunoglobulina E/imunologia , Análise Serial de Proteínas/métodos , Alérgenos/química , Alérgenos/genética , Sequência de Aminoácidos , Animais , Éxons/genética , Regulação da Expressão Gênica , Humanos , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Proteômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência
17.
J Invertebr Pathol ; 122: 55-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25196470

RESUMO

Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens.


Assuntos
Abelhas/microbiologia , Animais
18.
Vet Res ; 45: 40, 2014 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-24708344

RESUMO

Necrotic enteritis in broiler chickens is associated with netB positive Clostridium perfringens type A strains. It is known that C. perfringens strains isolated from outbreaks of necrotic enteritis are more capable of secreting factors inhibiting growth of other C. perfringens strains than strains isolated from the gut of healthy chickens. This characteristic could lead to extensive and selective presence of a strain that contains the genetic make-up enabling to secrete toxins that cause gut lesions. This report describes the discovery, purification, characterization and recombinant expression of a novel bacteriocin, referred to as perfrin, produced by a necrotic enteritis-associated netB-positive C. perfringens strain. Perfrin is a 11.5 kDa C-terminal fragment of a 22.9 kDa protein and showed no sequence homology to any currently known bacteriocin. The 11.5 kDa fragment can be cloned into Escherichia coli, and expression yielded an active peptide. PCR detection of the gene showed its presence in 10 netB-positive C. perfringens strains of broiler origin, and not in other C. perfringens strains tested (isolated from broilers, cattle, sheep, pigs, and humans). Perfrin and NetB are not located on the same genetic element since NetB is plasmid-encoded and perfrin is not. The bacteriocin has bactericidal activity over a wide pH-range but is thermolabile and sensitive to proteolytic digestion (trypsin, proteinase K). C. perfringens bacteriocins, such as perfrin, can be considered as an additional factor involved in the pathogenesis of necrotic enteritis in broilers.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Bacteriocinas/genética , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Doenças das Aves Domésticas/microbiologia , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Bacteriocinas/isolamento & purificação , Bacteriocinas/metabolismo , Sequência de Bases , Southern Blotting/veterinária , Infecções por Clostridium/microbiologia , Clostridium perfringens/genética , Eletroforese em Gel de Campo Pulsado/veterinária , Enterite/microbiologia , Enterite/veterinária , Enterotoxinas/genética , Enterotoxinas/metabolismo , Dados de Sequência Molecular , Necrose/microbiologia , Necrose/veterinária , Reação em Cadeia da Polimerase/veterinária , Homologia de Sequência
19.
PLoS One ; 9(2): e89175, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586572

RESUMO

Paenibacillus larvae, the causal agent of American Foulbrood disease (AFB), affects honey bee health worldwide. The present study investigates the effect of bodily fluids from honey bee larvae on growth velocity and transcription for this Gram-positive, endospore-forming bacterium. It was observed that larval fluids accelerate the growth and lead to higher bacterial densities during stationary phase. The genome-wide transcriptional response of in vitro cultures of P. larvae to larval fluids was studied by microarray technology. Early responses of P. larvae to larval fluids are characterized by a general down-regulation of oligopeptide and sugar transporter genes, as well as by amino acid and carbohydrate metabolic genes, among others. Late responses are dominated by general down-regulation of sporulation genes and up-regulation of phage-related genes. A theoretical mechanism of carbon catabolite repression is discussed.


Assuntos
Abelhas/metabolismo , Líquidos Corporais/metabolismo , Genoma Bacteriano/genética , Paenibacillus/crescimento & desenvolvimento , Paenibacillus/genética , Transcrição Genética , Animais , Abelhas/microbiologia , Ontologia Genética , Larva/metabolismo , Fenótipo , Fatores de Virulência/genética
20.
PLoS One ; 8(8): e72443, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991113

RESUMO

Since the last decade, unusually high honey bee colony losses have been reported mainly in North-America and Europe. Here, we report on a comprehensive bee pathogen screening in Belgium covering 363 bee colonies that were screened for 18 known disease-causing pathogens and correlate their incidence in summer with subsequent winter mortality. Our analyses demonstrate that, in addition to Varroa destructor, the presence of the trypanosomatid parasite Crithidia mellificae and the microsporidian parasite Nosema ceranae in summer are also predictive markers of winter mortality, with a negative synergy being observed between the two in terms of their effects on colony mortality. Furthermore, we document the first occurrence of a parasitizing phorid fly in Europe, identify a new fourth strain of Lake Sinai Virus (LSV), and confirm the presence of other little reported pathogens such as Apicystis bombi, Aphid Lethal Paralysis Virus (ALPV), Spiroplasma apis, Spiroplasma melliferum and Varroa destructor Macula-like Virus (VdMLV). Finally, we provide evidence that ALPV and VdMLV replicate in honey bees and show that viruses of the LSV complex and Black Queen Cell Virus tend to non-randomly co-occur together. We also noticed a significant correlation between the number of pathogen species and colony losses. Overall, our results contribute significantly to our understanding of honey bee diseases and the likely causes of their current decline in Europe.


Assuntos
Abelhas/parasitologia , Crithidia/patogenicidade , Estações do Ano , Animais , Bélgica , Interações Hospedeiro-Parasita , Humanos
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