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1.
PLoS Genet ; 15(11): e1008452, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710597

RESUMO

Trypanosomatid parasites are causative agents of important human and animal diseases such as sleeping sickness and leishmaniasis. Most trypanosomatids are transmitted to their mammalian hosts by insects, often belonging to Diptera (or true flies). These are called dixenous trypanosomatids since they infect two different hosts, in contrast to those that infect just insects (monoxenous). However, it is still unclear whether dixenous and monoxenous trypanosomatids interact similarly with their insect host, as fly-monoxenous trypanosomatid interaction systems are rarely reported and under-studied-despite being common in nature. Here we present the genome of monoxenous trypanosomatid Herpetomonas muscarum and discuss its transcriptome during in vitro culture and during infection of its natural insect host Drosophila melanogaster. The H. muscarum genome is broadly syntenic with that of human parasite Leishmania major. We also found strong similarities between the H. muscarum transcriptome during fruit fly infection, and those of Leishmania during sand fly infections. Overall this suggests Drosophila-Herpetomonas is a suitable model for less accessible insect-trypanosomatid host-parasite systems such as sand fly-Leishmania.


Assuntos
Interações Hospedeiro-Parasita/genética , Leishmania/genética , Psychodidae/parasitologia , Trypanosomatina/genética , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/parasitologia , Infecções por Euglenozoa/genética , Infecções por Euglenozoa/parasitologia , Infecções por Euglenozoa/transmissão , Humanos , Insetos Vetores/genética , Leishmania/patogenicidade , Leishmaniose/genética , Leishmaniose/parasitologia , Leishmaniose/transmissão , Psychodidae/genética , Trypanosomatina/patogenicidade
2.
PLoS Pathog ; 11(8): e1005127, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26317207

RESUMO

The co-infection cases involving dixenous Leishmania spp. (mostly of the L. donovani complex) and presumably monoxenous trypanosomatids in immunocompromised mammalian hosts including humans are well documented. The main opportunistic parasite has been identified as Leptomonas seymouri of the sub-family Leishmaniinae. The molecular mechanisms allowing a parasite of insects to withstand elevated temperature and substantially different conditions of vertebrate tissues are not understood. Here we demonstrate that L. seymouri is well adapted for the environment of the warm-blooded host. We sequenced the genome and compared the whole transcriptome profiles of this species cultivated at low and high temperatures (mimicking the vector and the vertebrate host, respectively) and identified genes and pathways differentially expressed under these experimental conditions. Moreover, Leptomonas seymouri was found to persist for several days in two species of Phlebotomus spp. implicated in Leishmania donovani transmission. Despite of all these adaptations, L. seymouri remains a predominantly monoxenous species not capable of infecting vertebrate cells under normal conditions.


Assuntos
Coinfecção/microbiologia , Infecções por Euglenozoa/genética , Leishmaniose Visceral/parasitologia , Trypanosomatina/genética , Adaptação Fisiológica/fisiologia , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Genes de Protozoários , Leishmania donovani , Estágios do Ciclo de Vida , Reação em Cadeia da Polimerase , Psychodidae/microbiologia , Transcriptoma , Trypanosomatina/crescimento & desenvolvimento
3.
J Fish Dis ; 37(9): 771-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23952070

RESUMO

Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no details on specific cellular and humoral reactions have been presented. By applying gene expression methods and immunohistochemical techniques, further details of immune processes in the affected skin can be presented. A population of I. necator was established in the laboratory and used to induce an experimental infection of juvenile rainbow trout. The course of infection was followed by sampling for parasite enumeration, immunohistochemistry (IHC) and quantitative PCR (qPCR) on days 0, 5, 9 and 14 post-infection. IHC showed a significant increase in the occurrence of IgM-positive cells in the skin of the infected fish, whereas IgT-positive cells were eliminated and the number of CD8-positive cells declined. qPCR studies supported the IHC findings showing a significant increase in IgM and a decrease in the CD8 gene expression. In addition, genes encoding innate immune genes such as lysozyme, SAA and cathelicidin 2 were up-regulated. Expression of cytokines (IL-1ß, IL-4/13A, IL-6, IL-8, IL-10), the cell marker CD4 and the transcription factor GATA3 showed a significant increase after infection. Cytokine profiling including up-regulation of IL-4/13A and IL-10 genes and transcription factor GATA3 connected to the proliferation of IgM producing lymphocytes suggests a partial shift towards a Th2 response associated with the I. necator infection.


Assuntos
Citocinas/genética , Infecções por Euglenozoa/veterinária , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica , Kinetoplastida/fisiologia , Oncorhynchus mykiss , Animais , Linfócitos T CD8-Positivos , Citocinas/metabolismo , Epiderme/imunologia , Epiderme/parasitologia , Infecções por Euglenozoa/genética , Infecções por Euglenozoa/imunologia , Infecções por Euglenozoa/parasitologia , Doenças dos Peixes/genética , Doenças dos Peixes/parasitologia , Imunoglobulina M/genética , Imunoglobulina M/metabolismo , Imuno-Histoquímica/veterinária , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária
4.
J Endocrinol ; 218(3): 287-97, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23814015

RESUMO

Despite clear physiological duress, rainbow trout (Oncorhynchus mykiss) infected with the pathogenic haemoflagellate Cryptobia salmositica do not appear to mount a cortisol stress response. Therefore, we hypothesized that the infection suppresses the stress response by inhibiting the key effectors of the hypothalamic-pituitary-interrenal (HPI) axis. To test this, we characterized the basal activity of the HPI axis and the cortisol response to air exposure in saline- and parasite-injected fish. All fish were sampled at 4 and 6 weeks post-injection (wpi). While both the treatment groups had resting plasma cortisol levels, the parasite-infected fish had lower levels of plasma ACTH than the control fish. Relative to the control fish, the infected fish had higher mRNA levels of brain pre-optic area corticotrophin-releasing factor (CRF) and pituitary CRF receptor type 1, no change in pituitary POMC-A1, -A2 and -B gene expression, higher and lower head kidney melanocortin 2 receptor mRNA levels at 4 and 6 wpi respectively and reduced gene expression of key proteins regulating interrenal steroidogenesis: StAR, cytochrome P450scc and 11ß-hydroxylase. The parasite-infected fish also had a reduced plasma cortisol response to a 60-s air exposure stressor. Superfusion of the head kidney tissues of the parasite-infected fish led to significantly lower ACTH-stimulated cortisol release rates than that observed in the control fish. These novel findings show that infection of rainbow trout with C. salmositica results in complex changes in the transcriptional activity of both central and peripheral regulators of the HPI axis and in a reduction in the interrenal capacity to synthesize cortisol.


Assuntos
Infecções por Euglenozoa/veterinária , Doenças dos Peixes/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Glândula Inter-Renal/metabolismo , Kinetoplastida/fisiologia , Oncorhynchus mykiss/parasitologia , Hormônio Adrenocorticotrópico/metabolismo , Animais , Hormônio Liberador da Corticotropina/metabolismo , Infecções por Euglenozoa/genética , Infecções por Euglenozoa/metabolismo , Infecções por Euglenozoa/parasitologia , Doenças dos Peixes/genética , Doenças dos Peixes/parasitologia , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Rim Cefálico/metabolismo , Hidrocortisona/metabolismo , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/metabolismo , Receptor Tipo 2 de Melanocortina/genética , Receptor Tipo 2 de Melanocortina/metabolismo , Estresse Fisiológico
5.
PLoS One ; 7(3): e33746, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22448269

RESUMO

Euglenids are a group of protists that comprises species with diverse feeding modes. One distinct and diversified clade of euglenids is photoautotrophic, and its members bear green secondary plastids. In this paper we present the plastid genome of the euglenid Eutreptiella, which we assembled from 454 sequencing of Eutreptiella gDNA. Comparison of this genome and the only other available plastid genomes of photosynthetic euglenid, Euglena gracilis, revealed that they contain a virtually identical set of 57 protein coding genes, 24 genes fewer than the genome of Pyramimonas parkeae, the closest extant algal relative of the euglenid plastid. Searching within the transcriptomes of Euglena and Eutreptiella showed that 6 of the missing genes were transferred to the nucleus of the euglenid host while 18 have been probably lost completely. Euglena and Eutreptiella represent the deepest bifurcation in the photosynthetic clade, and therefore all these gene transfers and losses must have happened before the last common ancestor of all known photosynthetic euglenids. After the split of Euglena and Eutreptiella only one additional gene loss took place. The conservation of gene content in the two lineages of euglenids is in contrast to the variability of gene order and intron counts, which diversified dramatically. Our results show that the early secondary plastid of euglenids was much more susceptible to gene losses and endosymbiotic gene transfers than the established plastid, which is surprisingly resistant to changes in gene content.


Assuntos
Evolução Biológica , Euglênidos/genética , Infecções por Euglenozoa/patologia , Genomas de Plastídeos , Plastídeos/genética , Simbiose/fisiologia , Infecções por Euglenozoa/genética , Filogenia
6.
Dev Comp Immunol ; 34(7): 705-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20144650

RESUMO

Social bees and other insects are frequently parasitized by a large range of different microorganisms. Among these is Crithidia bombi (Kinetoplastida: Trypanosomatidae), a common gut parasite of bumblebees, Bombus spp. (Insecta: Apidae). Bumblebees are important pollinators in commercial and natural environments. There are clear detrimental effects of C. bombi infections on the fitness of bumblebees. However, little has been known about how the bee's immune system responds to infections with trypanosome parasites. Here, we study the immune response of Bombus terrestris on infection by C. bombi. We measured the expression of four immune-related genes (Hemomucin, MyD88, Relish, and TEP7) using RT-qPCR in adult B. terrestris workers that were either healthy or infected with the trypanosome parasite C. bombi. The potential recognition gene Hemomucin was significantly upregulated in the infected bees. Further, there was substantial and significant variation in all four genes among different bumblebee colonies irrespective of infection status.


Assuntos
Abelhas/parasitologia , Crithidia/fisiologia , Infecções por Euglenozoa/veterinária , Animais , Abelhas/genética , Abelhas/imunologia , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Crithidia/genética , Crithidia/imunologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Infecções por Euglenozoa/genética , Infecções por Euglenozoa/imunologia , Infecções por Euglenozoa/parasitologia , Interações Hospedeiro-Parasita , Mucinas/genética , Mucinas/imunologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , RNA de Protozoário/química , RNA de Protozoário/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição , Transcrição Gênica
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