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1.
PLoS Genet ; 17(11): e1009880, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748554

RESUMO

In order to thrive in constantly changing environments, animals must adaptively respond to threatening events. Noxious stimuli are not only processed according to their absolute intensity, but also to their context. Adaptation processes can cause animals to habituate at different rates and degrees in response to permanent or repeated stimuli. Here, we used a forward genetic approach in Caenorhabditis elegans to identify a neuropeptidergic pathway, essential to prevent fast habituation and maintain robust withdrawal responses to repeated noxious stimuli. This pathway involves the FRPR-19A and FRPR-19B G-protein coupled receptor isoforms produced from the frpr-19 gene by alternative splicing. Loss or overexpression of each or both isoforms can impair withdrawal responses caused by the optogenetic activation of the polymodal FLP nociceptor neuron. Furthermore, we identified FLP-8 and FLP-14 as FRPR-19 ligands in vitro. flp-14, but not flp-8, was essential to promote withdrawal response and is part of the same genetic pathway as frpr-19 in vivo. Expression and cell-specific rescue analyses suggest that FRPR-19 acts both in the FLP nociceptive neurons and downstream interneurons, whereas FLP-14 acts from interneurons. Importantly, genetic impairment of the FLP-14/FRPR-19 pathway accelerated the habituation to repeated FLP-specific optogenetic activation, as well as to repeated noxious heat and harsh touch stimuli. Collectively, our data suggest that well-adjusted neuromodulation via the FLP-14/FRPR-19 pathway contributes to promote nociceptive signals in C. elegans and counteracts habituation processes that otherwise tend to rapidly reduce aversive responses to repeated noxious stimuli.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Neuropeptídeos/metabolismo , Nociceptividade , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Reação de Fuga , Genes de Helmintos , Temperatura Alta , Neurônios/metabolismo , Neuropeptídeos/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
2.
Nat Commun ; 12(1): 6706, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795249

RESUMO

Hox genes are highly conserved transcription factors renowned for their roles in the segmental patterning of the embryonic anterior-posterior (A/P) axis. We report functions for Hox genes in A/P tissue segmentation and transverse fission behavior underlying asexual reproduction in adult planarian flatworms, Schmidtea mediterranea. Silencing of each of the Hox family members identifies 5 Hox genes required for asexual reproduction. Among these, silencing of hox3 genes results in supernumerary fission segments, while silencing of post2b eliminates segmentation altogether. The opposing roles of hox3 and post2b in segmentation are paralleled in their respective regulation of fission behavior. Silencing of hox3 increases the frequency of fission behavior initiation while silencing of post2b eliminates fission behavior entirely. Furthermore, we identify a network of downstream effector genes mediating Hox gene functions, providing insight into their respective mechanisms of action. In particular, we resolve roles for post2b and effector genes in the functions of the marginal adhesive organ in fission behavior regulation. Collectively, our study establishes adult stage roles for Hox genes in the regulation of tissue segmentation and behavior associated with asexual reproduction.


Assuntos
Padronização Corporal/genética , Regulação da Expressão Gênica no Desenvolvimento , Genes de Helmintos/genética , Genes Homeobox/genética , Planárias/genética , Animais , Proteínas de Homeodomínio/genética , Hibridização in Situ Fluorescente , Microscopia Confocal , Microscopia Eletrônica de Varredura , Planárias/crescimento & desenvolvimento , Planárias/ultraestrutura , Interferência de RNA , RNA-Seq/métodos , Reprodução Assexuada/genética , Fatores de Transcrição/genética
3.
Nat Commun ; 12(1): 6181, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702841

RESUMO

The rhesus macaque provides a unique model of acquired immunity against schistosomes, which afflict >200 million people worldwide. By monitoring bloodstream levels of parasite-gut-derived antigen, we show that from week 10 onwards an established infection with Schistosoma mansoni is cleared in an exponential manner, eliciting resistance to reinfection. Secondary challenge at week 42 demonstrates that protection is strong in all animals and complete in some. Antibody profiles suggest that antigens mediating protection are the released products of developing schistosomula. In culture they are killed by addition of rhesus plasma, collected from week 8 post-infection onwards, and even more efficiently with post-challenge plasma. Furthermore, cultured schistosomula lose chromatin activating marks at the transcription start site of genes related to worm development and show decreased expression of genes related to lysosomes and lytic vacuoles involved with autophagy. Overall, our results indicate that enhanced antibody responses against the challenge migrating larvae mediate the naturally acquired protective immunity and will inform the route to an effective vaccine.


Assuntos
Schistosoma mansoni/fisiologia , Esquistossomose mansoni/imunologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Anticorpos Anti-Helmínticos/farmacologia , Antígenos de Helmintos/imunologia , Modelos Animais de Doenças , Epigênese Genética/efeitos dos fármacos , Feminino , Genes de Helmintos/genética , Granulócitos/imunologia , Histonas/metabolismo , Interações Hospedeiro-Parasita/imunologia , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Linfócitos/imunologia , Macaca mulatta/imunologia , Macaca mulatta/parasitologia , Masculino , Contagem de Ovos de Parasitas , Reinfecção/imunologia , Esquistossomose mansoni/parasitologia
4.
Genes (Basel) ; 12(8)2021 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-34440303

RESUMO

Trematode parthenitae have long been believed to form clonal populations, but clonal diversity has been discovered in this asexual stage of the lifecycle. Clonal polymorphism in the model species Himasthla elongata has been previously described, but the source of this phenomenon remains unknown. In this work, we traced cercarial clonal diversity using a simplified amplified fragment length polymorphism (SAFLP) method and characterised the nature of fragments in diverse electrophoretic bands. The repetitive elements were identified in both the primary sequence of the H. elongata genome and in the transcriptome data. Long-interspersed nuclear elements (LINEs) and long terminal repeat retrotransposons (LTRs) were found to represent an overwhelming majority of the genome and the transposon transcripts. Most sequenced fragments from SAFLP pattern contained the reverse transcriptase (RT, ORF2) domains of LINEs, and only a few sequences belonged to ORFs of LTRs and ORF1 of LINEs. A fragment corresponding to a CR1-like (LINE) spacer region was discovered and named CR1-renegade (CR1-rng). In addition to RT-containing CR1 transcripts, we found short CR1-rng transcripts in the redia transcriptome and short contigs in the mobilome. Probes against CR1-RT and CR1-rng presented strikingly different pictures in FISH mapping, despite both being fragments of CR1. In silico data and Southern blotting indicated that CR1-rng is not tandemly organised. CR1 involvement in clonal diversity is discussed.


Assuntos
Elementos de DNA Transponíveis , Heterocromatina/genética , Trematódeos/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Genes de Helmintos , Elementos Nucleotídeos Longos e Dispersos , Fases de Leitura Aberta , RNA Mensageiro/genética , Retroelementos , Transcriptoma
5.
Genes (Basel) ; 12(8)2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34440335

RESUMO

The nematode Caenorhabditis elegans has been a versatile model for understanding the molecular responses to abiotic stress and pathogens. In particular, the response to heat stress and virus infection has been studied in detail. The Orsay virus (OrV) is a natural virus of C. elegans and infection leads to intracellular infection and proteostatic stress, which activates the intracellular pathogen response (IPR). IPR related gene expression is regulated by the genes pals-22 and pals-25, which also control thermotolerance and immunity against other natural pathogens. So far, we have a limited understanding of the molecular responses upon the combined exposure to heat stress and virus infection. We test the hypothesis that the response of C. elegans to OrV infection and heat stress are co-regulated and may affect each other. We conducted a combined heat-stress-virus infection assay and found that after applying heat stress, the susceptibility of C. elegans to OrV was decreased. This difference was found across different wild types of C. elegans. Transcriptome analysis revealed a list of potential candidate genes associated with heat stress and OrV infection. Subsequent mutant screens suggest that pals-22 provides a link between viral response and heat stress, leading to enhanced OrV tolerance of C. elegans after heat stress.


Assuntos
Caenorhabditis elegans/virologia , Resposta ao Choque Térmico , Nodaviridae/patogenicidade , Infecções por Vírus de RNA/imunologia , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/imunologia , Suscetibilidade a Doenças , Genes de Helmintos
6.
Vet Parasitol ; 298: 109556, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34419708

RESUMO

Trichinellosis is a very important food-borne parasitic disease, that seriously endangers animal husbandry and food safety. Therefore, it is necessary to develop a safe and effective vaccine against Trichinella spiralis infection. In this experiment, invasive Lactobacillus plantarum carrying the FnBPA gene served as a live bacterial vector to deliver nucleic acids to the host to produce a novel oral nucleic acid vaccine. Coexpression of the T. spiralis cathepsin F-like protease 1 gene (TsCPF1) and murine IL-4 (mIL-4) by the nucleic acid vaccine was constructed and subsequently delivered to intestinal epithelial cells via invasive L. plantarum. Thirty-seven days after the first immunization, the experimental mice were challenged with 350 T. spiralis infective larvae by oral gavage. The results showed that mice orally immune-stimulated with invasive L. plantarum pValac-TsCPF1/pSIP409-FnBPA not only produce anti-TsCPF1-specific IgG antibodies, sIgA, Th1/Th2 cytokine distinctly increased but also intestinal damage and worm burden relieved compare to non-invasive TsCPF1 group (pValac-TsCPF1/pSIP409). Most notably, experimental mice immunized with invasive L. plantarum coexpressing TsCPF1 and mIL-4 (pValac-TsCPF1-IL-4/pSIP409-FnBPA) exhibited the highest protection efficiency against T. spiralis infection. The above results reveal that invasive L. plantarum-expressing the FnBPA protein improved mucosal and cellular immunity and enhanced resistance to T. spiralis. The nucleic acid vaccine delivered by invasive L. plantarum described in this study offers a novel idea for the prevention of T. spiralis.


Assuntos
Genes de Helmintos , Imunidade , Lactobacillus plantarum , Trichinella spiralis , Triquinelose , Vacinas de DNA , Animais , Genes de Helmintos/genética , Genes de Helmintos/imunologia , Interleucina-4/imunologia , Lactobacillus plantarum/genética , Lactobacillus plantarum/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Trichinella spiralis/imunologia , Triquinelose/prevenção & controle , Triquinelose/veterinária , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia
7.
Infect Genet Evol ; 95: 105035, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34384934

RESUMO

Equines were over decades considered to be infected by two morphologically virtually indistinguishable ascarid species, Parascaris univalens and Parascaris equorum. Reliable species discrimination is only possible using enzyme isoelectric focussing and karyotyping with P. univalens having one and P. equorum two chromosome pairs. However, presumably the complexity of both methods prevented their routine use in nearly all previous studies about prevalence and drug resistance of Parascaris spp. These have barely been performed on the species level although most studies stated presence of one or the other species. Recently, only P. univalens has been identified by karyotyping and the last published study identifying P. equorum dates back to 1989. In order to improve species-specific detection, molecular markers are required. Here, partial 12S rRNA, cytochrome oxidase I (COI) and complete internal transcribed spacer (ITS)-1 and - 2 sequences were obtained from 24 karyotyped Parascaris specimens from Poland and 6 German specimens (not karyotyped) and used in phylogenetic analyses with orthologous sequences from GenBank. All karyotyped specimens were identified as P. univalens. In the phylogenetic analysis, they formed very homogenous clusters for all target genes and in a multi-locus analysis. Within this cluster, almost all sequences from GenBank were also included, no matter if they had been assigned to P. univalens or P. equorum. However, a small number of P. univalens ITS and COI sequences originating from donkeys from a single farm in China formed a highly supported sister cluster suggesting that they might represent another Parascaris genotype or species. Our data also strongly suggest that nearly all ITS and COI sequences previously deposited in GenBank and assigned to P. equorum actually represent P. univalens. The fact that significantly different sequences can be found in Parascaris spp. suggests that PCR-based species diagnosis will be possible once molecular markers have been identified for P. equorum from karyotyped specimens.


Assuntos
Ascaridoidea/genética , Genes de Helmintos , Variação Genética , Animais , Genes Mitocondriais , Alemanha , Filogenia , Polônia
8.
Int J Mol Sci ; 22(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199120

RESUMO

Molting is essential for arthropods to grow. As one of the important arthropod pests in agriculture, key spider mite species (Tetranychus and Panonychus) can normally molt three times from the larva to adult stage within a week. This physiological strategy results in the short lifecycle of spider mites and difficulties in their control in the field. Long non-coding RNAs (lncRNAs) regulate transcriptional editing, cellular function, and biological processes. Thus, analysis of the lncRNAs in the spider mite molting process may provide new insights into their roles in the molting mechanism. For this purpose, we used high-throughput RNA-seq to examine the expression dynamics of lncRNAs and mRNAs in the molting process of different development stages in Panonychus citri. We identified 9199 lncRNAs from 18 transcriptomes. Analysis of the lncRNAs suggested that they were shorter and had fewer exons and transcripts than mRNAs. Among these, 356 lncRNAs were differentially expressed during three molting processes: late larva to early protonymph, late protonymph to early deutonymph, and late deutonymph to early adult. A time series profile analysis of differentially expressed lncRNAs showed that 77 lncRNAs were clustered into two dynamic expression profiles (Pattern a and Pattern c), implying that lncRNAs were involved in the molting process of spider mites. Furthermore, the lncRNA-mRNA co-expression networks showed that several differentially expressed hub lncRNAs were predicted to be functionally associated with typical molting-related proteins, such as cuticle protein and chitin biosynthesis. These data reveal the potential regulatory function of lncRNAs in the molting process and provide datasets for further analysis of lncRNAs and mRNAs in spider mites.


Assuntos
Genoma Helmíntico , Estudo de Associação Genômica Ampla , Muda/genética , RNA Longo não Codificante/genética , Tetranychidae/fisiologia , Animais , Biologia Computacional/métodos , Genes de Helmintos , Transcriptoma
9.
Gene ; 793: 145748, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34077775

RESUMO

The rice root-knot nematode Meloidogyne graminicola is a major biotic stress for the rice crop under upland, rain-fed lowland and irrigated cultivation conditions. Here, we present an improved draft genome assembly of M. graminicola IARI strain using the long-read sequencing approach (PacBio Sequel platform). The assembled genome size was 36.86 Mb with 514 contigs and N50 value of 105 kb. BUSCO estimated the genome to be 88.6% complete. Meloidogyne graminicola genome contained 17.83% repeat elements and showed 14,062 protein-coding gene models, 4,974 conserved orthologous genes, 561 putative secreted proteins, 49 RNAi pathway genes, 1,853 proteins involved in pathogen-host interactions, 1,575 carbohydrate-active enzymes, and 32,138 microsatellites. Five of the carbohydrate-active enzymes were found only in M. graminicola genome and were not present in any other analysed root-knot nematode genome. Together with the previous two genome assemblies, this improved genome assembly would facilitate comparative and functional genomics for M. graminicola.


Assuntos
Genes de Helmintos , Genoma Helmíntico , Proteínas de Helminto/genética , Oryza/parasitologia , Tylenchoidea/genética , Animais , Ontologia Genética , Tamanho do Genoma , Proteínas de Helminto/classificação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites , Anotação de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/parasitologia , Tylenchoidea/classificação
10.
Parasitol Int ; 84: 102398, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34087475

RESUMO

Tremiorchis is a monotypic genus of digenetic trematode (Plagiorchiidae: Plagiorchiinae), infecting the frogs Rana tigrina (Hoplobatrachus tigerinus) and R. cyanophlyctis (Euphlyctis cyanophlyctis). Metacercaria use to infect Rana tigrina (Hoplobatrachus tigerinus) and R. cyanophlyctis (Euphlyctis cyanophlyctis) as intermediate hosts, while the cercaria stage found from apple snail, Pila virens. Adults of T. ranarum harbor mature frogs of H. tigerinus and E. cyanophlyctis. Besides the frequent infection of Tremiorchis, no DNA sequence data are currently available for this monotypic genus. The present communication, deals with the sequence data for nuclear ribosomal genes, 18S, small internal transcribed spacers (ITS1-5.8S-ITS2) and 28S to molecularly characterize T. ranarum. Besides this, phylogenetic relationship among the members of the Plagiorchiida is also discussed in detail. An attempt has also been made to provide detailed molecular affinities of T. ranarum with other trematode genera.


Assuntos
Genes de Helmintos , RNA de Helmintos/análise , Trematódeos/classificação , Animais , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análise , Trematódeos/genética
11.
J Microbiol Methods ; 187: 106258, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34082051

RESUMO

The superfamily Opisthorchioidea encompasses the families Cryptogonimidae, Opisthorchiidae and Heterophyidae. These parasites depend on the aquatic environment and include marine and freshwater species. Some species, such as Clonorchis sinensis and Opisthorchis viverrini, have a high impact on public health with millions of infected people worldwide and have thus been the object of many studies and tool developments. However, for many species, tools for identification and detection are scarce. Although morphological descriptions have been used and are still important, they are often not efficient on the immature stages of these parasites. Thus, during the past few decades, molecular approaches for parasite identification have become commonplace. These approaches are efficient, quick and reliable. Nonetheless, for some parasites of the superfamily Opisthorchioidea, reference genomic data are limited. This study reviews available genetic data and molecular tools for the identification and/or the detection of this superfamily. Molecular data on this superfamily are mostly based on mitochondrial and ribosomal gene sequence analyses, especially on the cytochrome c oxidase subunit 1 gene and internal transcribed spacer regions respectively.


Assuntos
DNA de Helmintos/genética , Parasitologia/métodos , Trematódeos/classificação , Animais , Primers do DNA , DNA de Helmintos/análise , DNA Mitocondrial/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/análise , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Helmintos , Heterophyidae/classificação , Heterophyidae/genética , Heterophyidae/isolamento & purificação , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Opisthorchidae/classificação , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Técnica de Amplificação ao Acaso de DNA Polimórfico , Trematódeos/genética , Trematódeos/isolamento & purificação
12.
Folia Parasitol (Praha) ; 682021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33938815

RESUMO

Cats are important hosts for different zoonotic parasites that can be hazardous to human health. To date, few studies have attempted to identify the factors affecting parasitic infections in shelter animals. This study aims to analyse the presence of endoparasites in shelter cats in Tartu, Estonia, and identify factors affecting endoparasite prevalence and intensity. The risk factors considered were age, location (urban vs rural cats) and time spent in shelter. In total, 290 faecal samples were collected from cats at an animal shelter in 2015-2016 and investigated for endoparasites using the concentration flotation technique. In total, 138 shelter cats (47.6%) were infected with endoparasites and their overall prevalence was: Toxocara cati (36.6%), Cystoisospora spp. (12.4%), Taeniidae gen. sp. (4.1%), Toxoplasma gondii/Hammondia hammondi (3.4%), Eucoleus aerophilus (2.1%), Cryptosporidium spp. (2.1%), Ancylostoma sp. (0.7%) and Giardia sp. (0.7%). Coinfections occurred in 38 cats (13.1%) most frequently of T. cati and Cystoisospora spp. (4.5%), Cystoisospora spp. and T. gondii/H. hammondi (2.1%). Where species identification of cestode and nematode samples was not possible according to morphology, genetic analysis of the mitochondrial cox1 gene was carried out. DNA was successfully analysed for 6 out of 13 samples that required genetic identification, revealing Ancylostoma tubaeforme in one nematode sample and Hydatigera taeniaeformis in five cestode samples. Cats from rural areas had significantly higher endoparasite prevalence than cats from urban areas. Helminth prevalence decreased to some extent due to anthelmintic treatment in cats available for adoption (held ≥15 days in the shelter), whereas the prevalence of infection with protists increased significantly in these animals. It is important to note that the analysis revealed lower infection intensity for quarantine cats (held 1-14 days in the shelter) compared with cats available for adoption. The relatively high prevalence of endoparasites (including zoonotic) in shelter cats ready for adoption suggests that current anthelminthic procedures require improvements.


Assuntos
Gatos/parasitologia , Parasitos , Toxocara/isolamento & purificação , Fatores Etários , Ancylostoma/isolamento & purificação , Animais , Cestoides/isolamento & purificação , Coccídios/isolamento & purificação , Cryptosporidium/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Estônia/epidemiologia , Fezes/parasitologia , Genes de Helmintos , Giardia/isolamento & purificação , Giardíase , Helmintos , Nematoides/isolamento & purificação , Parasitos/classificação , Parasitos/isolamento & purificação , Parasitos/patogenicidade , Prevalência , Fatores de Risco , Toxoplasma/isolamento & purificação , Zoonoses/parasitologia
13.
Folia Parasitol (Praha) ; 682021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33871382

RESUMO

Two new species of philometrid nematodes (Philometridae) from needlefishes (Belonidae) in Florida are described based on morphological and genetic characteristics: Philometra aequispiculata sp. n. (males and females) collected from the ovary of Strongylura marina (Walbaum) (type host) and Strongylura notata (Poey), and Philometra notatae sp. n. (females) from the swimbladder of S. notata. Both species are described and illustrated based on light and scanning electron microscopical examinations. Morphologically, P. aequispiculata sp. n. differs from all congeners mainly in the unique structure of the distal tip of the gubernaculum, whereas P. notatae sp. n. is mainly characterised by the presence of eight markedly large cephalic papillae of the outer circle in gravid and subgravid females, the body length of the gravid female (54 mm) and by the absence of caudal projections. Molecular characterisation of the new species was assessed from phylogenetic analysis of mitochondrial cytochrome c oxidase I (COI) and SSU rRNA small-subunit ribosomal RNA (SSU) sequences among closely related philometrids by way of Bayesian inference. Phylogenetic reconstructions based on COI and SSU sequences show each of the new species comprise discrete ancestor-descendent lineages.


Assuntos
Beloniformes/parasitologia , Nematoides , Sacos Aéreos/parasitologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Estuários , Feminino , Florida , Genes de Helmintos , Masculino , Microscopia Eletrônica de Varredura , Nematoides/anatomia & histologia , Nematoides/genética , Nematoides/isolamento & purificação , Ovário/parasitologia , Filogenia , RNA Ribossômico/genética , Especificidade da Espécie
14.
Parasitology ; 148(9): 1019-1029, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33896429

RESUMO

Echinococcus granulosus sensu lato (s.l.) is a zoonotic parasite that causes cystic echinococcosis (CE) in humans. However, E. granulosus sensu stricto (s.s.) is considered the predominant species in CE infections worldwide. According to the population genetic diversity and structure of E. granulosus s.l., gene flow can explain the parasite drift among the neighbouring countries of Pakistan. The mitochondrial (mt) co1 (n = 47), nadh1 (n = 37) and cytb (n = 35) nucleotide sequences of E. granulosus s.l. isolates from Pakistan, Iran, China and India were retrieved from the National Centre for Biotechnology Information database to determine the genealogical relationships. The sequences were grouped as the mt-co1 (genotypes G1 and G3, G6-G7), mt-cytb (genotypes G1 and G3), and mt-nadh1(genotypes G1 and G3). The data were analysed using bioinformatic tools. A total of 19 polymorphic sites for the mt-co1 sequence (374 bp) were observed of which 31.6% (6/19) were parsimony-informative sites. Unique singleton haplotypes within the E. granulosus s.s. haplotype network based on the mt-co1 gene were highly prevalent (68.4%; 13/19) in Pakistani isolates followed by Chinese, Indian and Iranian isolates; four polymorphic sites were detected in the E. canadensis (G6/G7). In E. canadensis mt-co1 haplotype network, 75% (3/4) unique singleton haplotypes were from the Iranian isolates. Twelve polymorphic sites were found using the mt-cytb sequence (547 bp); 25% (3/12) were parsimony-informative and there were 66.7% (8/12) unique singleton haplotypes within the mt-cytb haplotype network in E. granulosus s.s. with the most reported from Pakistan followed by Iran and China. 20 polymorphic sites were detected in E. granulosus s.s. mt-nadh1 sequences (743 bp); 20% (4/20) were parsimony-informative. There were 66.7% (8/12) main single haplotypes within the mt-nadh1 haplotype network, with the most reported from Pakistan followed by that from India, Iran and China. The sequence analyses show low nucleotide diversity and high haplotype diversity in general.


Assuntos
Citocromos b/genética , Echinococcus granulosus/crescimento & desenvolvimento , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Helmintos , Genes Mitocondriais , Proteínas de Helminto/genética , NAD/genética , Animais , China , Haplótipos , Índia , Irã (Geográfico) , Paquistão
15.
Folia Parasitol (Praha) ; 682021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33847601

RESUMO

South African clinids are a major component of the temperate intertidal regions that are also known to participate in life cycles and transmission of several groups of parasites. However, the knowledge of trematode diversity of these fishes is incomplete. In this study, two species of Clinus Cuvier, the super klipfish Clinus superciliosus (Linnaeus) and the bluntnose klipfish Clinus cottoides Valenciennes, were collected from six localities along the South African coast and examined for the presence of trematodes. Metacercariae of Cardiocephaloides Sudarikov, 1959 were found in the eye vitreous humour and brain of C. superciliosus and in the eye vitreous humour of C. cottoides. Detailed analyses integrating morphological and molecular sequence data (28S rDNA, ITS2 rDNA-region, and COI mtDNA) revealed that these belong to two species, Cardiocephaloides physalis (Lutz, 1926) and an unknown species of Cardiocephaloides. This study provides the first report of clinid fishes serving as intermediate hosts for trematodes, reveals that the diversity of Cardiocephaloides in South Africa is higher than previously recorded, and highlights the need for further research to elucidate the life cycles of these trematode species. The broad geographical distribution of Cardiocephaloides spp. was confirmed in the present study based on molecular sequence data. The host-parasite interactions between clinid fishes and metacercariae of Cardiocephaloides are yet to be explored.


Assuntos
Perciformes/parasitologia , Trematódeos , Animais , DNA Ribossômico/genética , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Genes de Helmintos , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Metacercárias/anatomia & histologia , Metacercárias/classificação , Metacercárias/genética , Metacercárias/isolamento & purificação , Filogenia , África do Sul , Trematódeos/anatomia & histologia , Trematódeos/classificação , Trematódeos/genética , Trematódeos/isolamento & purificação , Infecções por Trematódeos/parasitologia
16.
Parasitol Res ; 120(6): 2077-2086, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33864104

RESUMO

We report on the genetic identity of 36 Echinococcus cysts that were collected during a recent slaughterhouse survey of 810 locally bred camels (dromedaries) in the Eastern Province of the Kingdom of Saudi Arabia. Analysis of a partial nad1 gene sequence showed that the majority (n = 29) belonged to E. granulosus sensu stricto, four to E. canadensis G6/7, and three to E. ortleppi. Eight of the 29 E. granulosus s.s. cysts contained protoscoleces; all other cysts were calcified and non-viable. This is the first report of the presence E. ortleppi from the Arabian Peninsula, a parasite that is typically transmitted via cattle. The results indicate widespread infection of camels with CE in eastern Saudi Arabia and an active role of camels in the lifecycles of at least E. granulosus s.s.. Complete cox1 haplotype analysis of 21 E. granulosus s.s. isolates shows that the majority of variants circulating in eastern Saudi Arabia is distinct from but closely related to haplotypes from neighboring countries in the Middle East, which indicates the presence of this parasite in KSA for a longer period of time. All isolates of E. granulosus s.s. in this study belonged to the G1 cluster, although the G3 genotype has previously also been reported from the Middle East.


Assuntos
Camelus/parasitologia , Equinococose/veterinária , Echinococcus granulosus/genética , Matadouros , Animais , DNA de Helmintos/genética , Equinococose/parasitologia , Echinococcus granulosus/classificação , Echinococcus granulosus/isolamento & purificação , Genes de Helmintos/genética , Variação Genética , Genótipo , Haplótipos , Filogenia , Arábia Saudita
17.
Sci Rep ; 11(1): 8254, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859232

RESUMO

The human and canine parasitic nematode Strongyloides stercoralis utilizes an XX/XO sex determination system, with parasitic females reproducing by mitotic parthenogenesis and free-living males and females reproducing sexually. However, the genes controlling S. stercoralis sex determination and male development are unknown. We observed precocious development of rhabditiform males in permissive hosts treated with corticosteroids, suggesting that steroid hormones can regulate male development. To examine differences in transcript abundance between free-living adult males and other developmental stages, we utilized RNA-Seq. We found two clusters of S. stercoralis-specific genes encoding predicted transmembrane proteins that are only expressed in free-living males. We additionally identified homologs of several genes important for sex determination in Caenorhabditis species, including mab-3, tra-1, fem-2, and sex-1, which may have similar functions. However, we identified three paralogs of gld-1; Ss-qki-1 transcripts were highly abundant in adult males, while Ss-qki-2 and Ss-qki-3 transcripts were highly abundant in adult females. We also identified paralogs of pumilio domain-containing proteins with sex-specific transcripts. Intriguingly, her-1 appears to have been lost in several parasite lineages, and we were unable to identify homologs of tra-2 outside of Caenorhabditis species. Together, our data suggest that different mechanisms control male development in S. stercoralis and Caenorhabditis species.


Assuntos
Caenorhabditis/genética , Genes de Helmintos/genética , Genes de Helmintos/fisiologia , Proteínas de Helminto/genética , Proteínas de Helminto/fisiologia , Processos de Determinação Sexual/genética , Strongyloides stercoralis/genética , Transcrição Genética , Animais , Caenorhabditis/fisiologia , Feminino , Hormônios Esteroides Gonadais/fisiologia , Masculino , Modelos Genéticos , Strongyloides stercoralis/fisiologia
18.
J Virol ; 95(12)2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33827942

RESUMO

Host-pathogen interactions play a major role in evolutionary selection and shape natural genetic variation. The genetically distinct Caenorhabditis elegans strains, Bristol N2 and Hawaiian CB4856, are differentially susceptible to the Orsay virus (OrV). Here, we report the dissection of the genetic architecture of susceptibility to OrV infection. We compare OrV infection in the relatively resistant wild-type CB4856 strain to the more susceptible canonical N2 strain. To gain insight into the genetic architecture of viral susceptibility, 52 fully sequenced recombinant inbred lines (CB4856 × N2 RILs) were exposed to OrV. This led to the identification of two loci on chromosome IV associated with OrV resistance. To verify the two loci and gain additional insight into the genetic architecture controlling virus infection, introgression lines (ILs) that together cover chromosome IV, were exposed to OrV. Of the 27 ILs used, 17 had an CB4856 introgression in an N2 background, and 10 had an N2 introgression in a CB4856 background. Infection of the ILs confirmed and fine-mapped the locus underlying variation in OrV susceptibility, and we found that a single nucleotide polymorphism in cul-6 may contribute to the difference in OrV susceptibility between N2 and CB4856. An allele swap experiment showed the strain CB4856 became as susceptible as the N2 strain by having an N2 cul-6 allele, although having the CB4856 cul-6 allele did not increase resistance in N2. In addition, we found that multiple strains with nonoverlapping introgressions showed a distinct infection phenotype from the parental strain, indicating that there are punctuated locations on chromosome IV determining OrV susceptibility. Thus, our findings reveal the genetic complexity of OrV susceptibility in C. elegans and suggest that viral susceptibility is governed by multiple genes.IMPORTANCE Genetic variation determines the viral susceptibility of hosts. Yet, pinpointing which genetic variants determine viral susceptibility remains challenging. Here, we have exploited the genetic tractability of the model organism Caenorhabditis elegans to dissect the genetic architecture of Orsay virus infection. Our results provide novel insight into natural determinants of Orsay virus infection.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/virologia , Cromossomos/genética , Proteínas Culina/genética , Variação Genética , Nodaviridae/patogenicidade , Locos de Características Quantitativas , Animais , Genes de Helmintos , Predisposição Genética para Doença , Interações Hospedeiro-Patógeno , Herança Multifatorial , Nodaviridae/fisiologia , Polimorfismo de Nucleotídeo Único , Carga Viral
19.
Zootaxa ; 4963(1): zootaxa.4963.1.13, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33903573

RESUMO

García Coy (1994) described the hystrignathid nematode Longior alius García Coy, 1994 parasitizing the passalid beetle Antillanax pertyi (Kaup, 1869) from Guantánamo province, Eastern Cuba. Morffe García (2011) continued the studies on Cuban Longior and described L. longior Morffe García, 2011. Morffe et al. (2018) redescribed L. longior with the aid of SEM and molecular techniques. In their research the authors studied Longior individuals from the same host species and a locality close to the type locality of L. alius and compared their morphology, measurements and DNA markers with other material of L. longior. As a result of this analysis Morffe et al. (2018) concluded that L. alius and L. longior are conspecific and proposed L. alius as a synonym of L. longior.


Assuntos
Besouros , Oxyurida , Animais , Besouros/parasitologia , Cuba , Genes de Helmintos/genética , Microscopia Eletrônica de Varredura , Oxyurida/classificação , Oxyurida/genética , Oxyurida/ultraestrutura , Especificidade da Espécie
20.
Parasitol Int ; 83: 102357, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33901678

RESUMO

It is estimated that one billion people globally are infected by parasitic nematodes, with children, pregnant women, and the elderly particularly susceptible to morbidity from infection. Control methods are limited to de-worming, which is hampered by rapid re-infection and the inevitable development of anthelmintic resistance. One family of proteins that has been implicated in nematode anthelmintic resistance are the ATP binding cassette (ABC) transporters. ABC transporters are characterized by a highly conserved ATP-binding domain and variable transmembrane regions. A growing number of studies have associated ABC transporters in anthelmintic resistance through a protective mechanism of drug efflux. Genetic deletion of P glycoprotein type ABC transporters in Caenorhabditis elegans demonstrated increased sensitivity to anthelmintics, while in the livestock parasite, Haemonchus contortus, anthelmintic use has been shown to increase the expression of ATP transporter genes. These studies as well as others, provide evidence for a potential role of ABC transporters in drug resistance in nematodes. In order to understand more about the family of ABC transporters, we used hidden Markov models to predict ABC transporter proteins from 108 species across the phylum Nematoda and use these data to analyze patterns of diversification and loss in diverse nematode species. We also examined temporal patterns of expression for the ABC transporter family within the filarial nematode Brugia malayi and identify cases of differential expression across diverse life-cycle stages. Taken together, our data provide a comprehensive overview of ABC transporters in diverse nematode species and identify examples of gene loss and diversification in nematodes based on lifestyle and taxonomy.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Genes de Helmintos/genética , Variação Genética , Nematoides/genética , Animais
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