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1.
Nature ; 625(7996): 788-796, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029793

RESUMO

The expansion of the neocortex, a hallmark of mammalian evolution1,2, was accompanied by an increase in cerebellar neuron numbers3. However, little is known about the evolution of the cellular programmes underlying the development of the cerebellum in mammals. In this study we generated single-nucleus RNA-sequencing data for around 400,000 cells to trace the development of the cerebellum from early neurogenesis to adulthood in human, mouse and the marsupial opossum. We established a consensus classification of the cellular diversity in the developing mammalian cerebellum and validated it by spatial mapping in the fetal human cerebellum. Our cross-species analyses revealed largely conserved developmental dynamics of cell-type generation, except for Purkinje cells, for which we observed an expansion of early-born subtypes in the human lineage. Global transcriptome profiles, conserved cell-state markers and gene-expression trajectories across neuronal differentiation show that cerebellar cell-type-defining programmes have been overall preserved for at least 160 million years. However, we also identified many orthologous genes that gained or lost expression in cerebellar neural cell types in one of the species or evolved new expression trajectories during neuronal differentiation, indicating widespread gene repurposing at the cell-type level. In sum, our study unveils shared and lineage-specific gene-expression programmes governing the development of cerebellar cells and expands our understanding of mammalian brain evolution.


Assuntos
Cerebelo , Evolução Molecular , Mamíferos , Neurogênese , Animais , Humanos , Camundongos , Linhagem da Célula/genética , Cerebelo/citologia , Cerebelo/embriologia , Cerebelo/crescimento & desenvolvimento , Feto/citologia , Feto/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Neurogênese/genética , Neurônios/citologia , Neurônios/metabolismo , Gambás/embriologia , Gambás/crescimento & desenvolvimento , Células de Purkinje/citologia , Células de Purkinje/metabolismo , Análise da Expressão Gênica de Célula Única , Especificidade da Espécie , Transcriptoma , Mamíferos/embriologia , Mamíferos/crescimento & desenvolvimento
2.
Cell ; 150(1): 29-38, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22770213

RESUMO

Regulatory T (Treg) cells, whose differentiation and function are controlled by X chromosome-encoded transcription factor Foxp3, are generated in the thymus (tTreg) and extrathymically (peripheral, pTreg), and their deficiency results in fatal autoimmunity. Here, we demonstrate that a Foxp3 enhancer, conserved noncoding sequence 1 (CNS1), essential for pTreg but dispensable for tTreg cell generation, is present only in placental mammals. CNS1 is largely composed of mammalian-wide interspersed repeats (MIR) that have undergone retrotransposition during early mammalian radiation. During pregnancy, pTreg cells specific to a model paternal alloantigen were generated in a CNS1-dependent manner and accumulated in the placenta. Furthermore, when mated with allogeneic, but not syngeneic, males, CNS1-deficient females showed increased fetal resorption accompanied by increased immune cell infiltration and defective remodeling of spiral arteries. Our results suggest that, during evolution, a CNS1-dependent mechanism of extrathymic differentiation of Treg cells emerged in placental animals to enforce maternal-fetal tolerance.


Assuntos
Tolerância Imunológica , Mamíferos/imunologia , Placenta/citologia , Placenta/imunologia , Gravidez/imunologia , Linfócitos T Reguladores/imunologia , Animais , Elementos Facilitadores Genéticos , Feminino , Feto/imunologia , Fatores de Transcrição Forkhead/genética , Humanos , Masculino , Mamíferos/genética , Camundongos , Gambás
3.
Proc Natl Acad Sci U S A ; 121(42): e2310047121, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39378090

RESUMO

In the first live-bearing mammals, pregnancy was likely short and ended with a brief period of inflammatory maternal-fetal interaction. This mode of reproduction has been retained in many marsupials. While inflammation is key to successful implantation in eutherians, a key innovation in eutherians is the ability to switch off this inflammation after it has been initiated. This extended period, in which inflammation is suppressed, likely allowed for an extended period of placentation. Extended placentation has evolved independently in one lineage of marsupials, the macropodids (wallabies and kangaroos), with placentation lasting beyond the 2 to 4 d seen in other marsupial taxa, which allows us to investigate the role of inflammation response after attachment in the extension of placentation in mammals. By comparing gene expression changes at attachment in three marsupial species, the tammar wallaby, opossum, and fat-tailed dunnart, we show that inflammatory attachment is an ancestral feature of marsupial implantation. In contrast to eutherians, where attachment-related (quasi-) inflammatory reaction is even involved in epitheliochorial placentation (e.g., pig), this study found no evidence of a distinct attachment-related reaction in wallabies. Instead, only a small number of inflammatory genes are expressed at distinct points of gestation, including IL6 before attachment, LIF throughout placentation, and prostaglandins before birth. During parturition, a more distinct inflammatory reaction is detectable, likely involved in precipitating the parturition cascade similar to eutherians. We suggest that in wallaby, extended gestation became possible by avoiding an inflammatory attachment reaction, which is a different strategy than seen in eutherians.


Assuntos
Evolução Biológica , Inflamação , Macropodidae , Placentação , Animais , Feminino , Gravidez , Macropodidae/genética , Inflamação/genética , Placenta/metabolismo , Implantação do Embrião/genética , Gambás
4.
Nature ; 588(7839): 642-647, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33177713

RESUMO

Gene-expression programs define shared and species-specific phenotypes, but their evolution remains largely uncharacterized beyond the transcriptome layer1. Here we report an analysis of the co-evolution of translatomes and transcriptomes using ribosome-profiling and matched RNA-sequencing data for three organs (brain, liver and testis) in five mammals (human, macaque, mouse, opossum and platypus) and a bird (chicken). Our within-species analyses reveal that translational regulation is widespread in the different organs, in particular across the spermatogenic cell types of the testis. The between-species divergence in gene expression is around 20% lower at the translatome layer than at the transcriptome layer owing to extensive buffering between the expression layers, which especially preserved old, essential and housekeeping genes. Translational upregulation specifically counterbalanced global dosage reductions during the evolution of sex chromosomes and the effects of meiotic sex-chromosome inactivation during spermatogenesis. Despite the overall prevalence of buffering, some genes evolved faster at the translatome layer-potentially indicating adaptive changes in expression; testis tissue shows the highest fraction of such genes. Further analyses incorporating mass spectrometry proteomics data establish that the co-evolution of transcriptomes and translatomes is reflected at the proteome layer. Together, our work uncovers co-evolutionary patterns and associated selective forces across the expression layers, and provides a resource for understanding their interplay in mammalian organs.


Assuntos
Evolução Molecular , Mamíferos/genética , Biossíntese de Proteínas , Transcriptoma/genética , Animais , Encéfalo/metabolismo , Galinhas/genética , Feminino , Genes Ligados ao Cromossomo X/genética , Humanos , Fígado/metabolismo , Macaca/genética , Masculino , Camundongos , Gambás/genética , Especificidade de Órgãos/genética , Ornitorrinco/genética , Biossíntese de Proteínas/genética , RNA-Seq , Ribossomos/metabolismo , Cromossomos Sexuais/genética , Especificidade da Espécie , Espermatogênese/genética , Testículo/metabolismo , Regulação para Cima
5.
Nature ; 571(7766): 505-509, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31243369

RESUMO

The evolution of gene expression in mammalian organ development remains largely uncharacterized. Here we report the transcriptomes of seven organs (cerebrum, cerebellum, heart, kidney, liver, ovary and testis) across developmental time points from early organogenesis to adulthood for human, rhesus macaque, mouse, rat, rabbit, opossum and chicken. Comparisons of gene expression patterns identified correspondences of developmental stages across species, and differences in the timing of key events during the development of the gonads. We found that the breadth of gene expression and the extent of purifying selection gradually decrease during development, whereas the amount of positive selection and expression of new genes increase. We identified differences in the temporal trajectories of expression of individual genes across species, with brain tissues showing the smallest percentage of trajectory changes, and the liver and testis showing the largest. Our work provides a resource of developmental transcriptomes of seven organs across seven species, and comparative analyses that characterize the development and evolution of mammalian organs.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Organogênese/genética , Transcriptoma/genética , Animais , Evolução Biológica , Galinhas/genética , Feminino , Humanos , Macaca mulatta/genética , Masculino , Camundongos , Gambás/genética , Coelhos , Ratos
6.
Nature ; 571(7766): 510-514, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31243368

RESUMO

Although many long noncoding RNAs (lncRNAs) have been identified in human and other mammalian genomes, there has been limited systematic functional characterization of these elements. In particular, the contribution of lncRNAs to organ development remains largely unexplored. Here we analyse the expression patterns of lncRNAs across developmental time points in seven major organs, from early organogenesis to adulthood, in seven species (human, rhesus macaque, mouse, rat, rabbit, opossum and chicken). Our analyses identified approximately 15,000 to 35,000 candidate lncRNAs in each species, most of which show species specificity. We characterized the expression patterns of lncRNAs across developmental stages, and found many with dynamic expression patterns across time that show signatures of enrichment for functionality. During development, there is a transition from broadly expressed and conserved lncRNAs towards an increasing number of lineage- and organ-specific lncRNAs. Our study provides a resource of candidate lncRNAs and their patterns of expression and evolutionary conservation across mammalian organ development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Especificidade de Órgãos/genética , Organogênese/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Especificidade da Espécie , Animais , Atlas como Assunto , Galinhas/genética , Evolução Molecular , Feminino , Humanos , Macaca mulatta/genética , Masculino , Camundongos , Gambás/genética , Proteínas/genética , RNA Longo não Codificante/análise , Coelhos , Ratos
7.
Nucleic Acids Res ; 51(22): 12508-12521, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37971311

RESUMO

Cellular DNA is subject to damage from a multitude of sources and repair or bypass of sites of damage utilize an array of context or cell cycle dependent systems. The recognition and removal of oxidatively damaged bases is the task of DNA glycosylases from the base excision repair pathway utilizing two structural families that excise base lesions in a wide range of DNA contexts including duplex, single-stranded and bubble structures arising during transcription. The mammalian NEIL2 glycosylase of the Fpg/Nei family excises lesions from each of these DNA contexts favoring the latter two with a preference for oxidized cytosine products and abasic sites. We have determined the first liganded crystal structure of mammalian NEIL2 in complex with an abasic site analog containing DNA duplex at 2.08 Å resolution. Comparison to the unliganded structure revealed a large interdomain conformational shift upon binding the DNA substrate accompanied by local conformational changes in the C-terminal domain zinc finger and N-terminal domain void-filling loop necessary to position the enzyme on the DNA. The detailed biochemical analysis of NEIL2 with an array of oxidized base lesions indicates a significant preference for its lyase activity likely to be paramount when interpreting the biological consequences of variants.


Assuntos
DNA Glicosilases , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Gambás , Animais , Humanos , DNA/química , Dano ao DNA , DNA Glicosilases/química , DNA Glicosilases/metabolismo , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/química , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Mamíferos/genética , Dedos de Zinco , Conformação Proteica
8.
PLoS Genet ; 18(2): e1010040, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35130272

RESUMO

During meiotic prophase I, homologous chromosomes pair, synapse and recombine in a tightly regulated process that ensures the generation of genetically variable haploid gametes. Although the mechanisms underlying meiotic cell division have been well studied in model species, our understanding of the dynamics of meiotic prophase I in non-traditional model mammals remains in its infancy. Here, we reveal key meiotic features in previously uncharacterised marsupial species (the tammar wallaby and the fat-tailed dunnart), plus the fat-tailed mouse opossum, with a focus on sex chromosome pairing strategies, recombination and meiotic telomere homeostasis. We uncovered differences between phylogroups with important functional and evolutionary implications. First, sex chromosomes, which lack a pseudo-autosomal region in marsupials, had species specific pairing and silencing strategies, with implications for sex chromosome evolution. Second, we detected two waves of γH2AX accumulation during prophase I. The first wave was accompanied by low γH2AX levels on autosomes, which correlated with the low recombination rates that distinguish marsupials from eutherian mammals. In the second wave, γH2AX was restricted to sex chromosomes in all three species, which correlated with transcription from the X in tammar wallaby. This suggests non-canonical functions of γH2AX on meiotic sex chromosomes. Finally, we uncover evidence for telomere elongation in primary spermatocytes of the fat-tailed dunnart, a unique strategy within mammals. Our results provide new insights into meiotic progression and telomere homeostasis in marsupials, highlighting the importance of capturing the diversity of meiotic strategies within mammals.


Assuntos
Pareamento Cromossômico/fisiologia , Cromossomos Sexuais/fisiologia , Telômero/fisiologia , Animais , Macropodidae/genética , Marsupiais/genética , Meiose/genética , Meiose/fisiologia , Prófase Meiótica I/fisiologia , Gambás/genética , Cromossomos Sexuais/genética , Telômero/genética , Cromossomo X/genética , Cromossomo Y/genética
9.
Mol Biol Evol ; 40(2)2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36721950

RESUMO

Genomic imprinting is a parent-of-origin-specific expression phenomenon that plays fundamental roles in many biological processes. In animals, imprinting is only observed in therian mammals, with ∼200 imprinted genes known in humans and mice. The imprinting pattern in marsupials has been minimally investigated by examining orthologs to known eutherian imprinted genes. To identify marsupial-specific imprinting in an unbiased way, we performed RNA-seq studies on samples of fetal brain and placenta from the reciprocal cross progeny of two laboratory opossum stocks. We inferred allele-specific expression for >3,000 expressed genes and discovered/validated 13 imprinted genes, including three previously known imprinted genes, Igf2r, Peg10, and H19. We estimate that marsupials imprint ∼60 autosomal genes, which is a much smaller set compared with eutherians. Among the nine novel imprinted genes, three noncoding RNAs have no known homologs in eutherian mammals, while the remaining genes have important functions in pluripotency, transcription regulation, nucleolar homeostasis, and neural differentiation. Methylation analyses at promoter CpG islands revealed differentially methylated regions in five of these marsupial-specific imprinted genes, suggesting that differential methylation is a common mechanism in the epigenetic regulation of marsupial imprinting. Clustering and co-regulation were observed at marsupial imprinting loci Pou5f3-Npdc1 and Nkrfl-Ipncr2, but eutherian-type multi-gene imprinting clusters were not detected. Also differing from eutherian mammals, the brain and placenta imprinting profiles are remarkably similar in opossums, presumably due to the shared origin of these organs from the trophectoderm. Our results contribute to a fuller understanding of the origin, evolution, and mechanisms of genomic imprinting in therian mammals.


Assuntos
Marsupiais , Gravidez , Humanos , Feminino , Animais , Camundongos , Marsupiais/genética , Metilação de DNA , Epigênese Genética , Duplicação Gênica , Impressão Genômica , Gambás/genética , Mamíferos , Eutérios/genética
10.
Parasitology ; 151(7): 637-649, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38682282

RESUMO

A total of 32 taxa of helminths were recovered from 52 individuals corresponding to 17 species of didelphiomorph marsupials collected across Bolivia. From these, 20 taxa are registered for the first time in this landlocked South American country, including the cestode Mathevotaenia bivittata, and the nematodes Moennigia sp., Travassostrongylus callis, Viannaia didelphis, V. hamata, V. metachirops, V. minispicula, V. philanderi, V. simplicispicula, V. skrjabini, V. viannai, Cruzia tentaculata, Monodelphoxyuris dollmeiri, Neohilgertia venusti, Pterygodermatites elegans, Pterygodermatites jeagerskioldi, Spirura guianensis, Gongylonemoides marsupialis, Turgida turgida and Trichuris reesali. We report for the first time parasites for Marmosops bishopi, Monodelphis emiliae, Monodeplhis glirina, Monodelphis sanctarosae, Monodelphis peruviana and Thylamys sponsorius and document 38 new records of parasites infecting marsupials. Twenty-six taxa of helminths infect 2 or more species of didelphiomorph marsupials, with the exception of Travassostrongylus callis, Viannaia didelphis, V. hamata, V. minispicula and V. hamate, which infected individuals of a single species.


Assuntos
Helmintíase Animal , Helmintos , Animais , Bolívia/epidemiologia , Helmintíase Animal/parasitologia , Helmintíase Animal/epidemiologia , Helmintos/classificação , Helmintos/isolamento & purificação , Gambás/parasitologia , Masculino , Feminino , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/epidemiologia , Prevalência
11.
Exp Appl Acarol ; 92(3): 463-477, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38361037

RESUMO

Ticks are hematophagous arthropods and, during feeding, may transmit pathogens to vertebrate hosts, including humans. This study aimed to investigate the presence of Rickettsia spp. in ticks collected between 2010 and 2013 from free-ranging capybaras (Hydrochoerus hydrochaeris) and opossums (Didelphis albiventris) that inhabit Sabiá Park in Uberlândia, Brazil. Overall, 1,860 ticks were collected: 1,272 (68.4%) from capybaras (487 of the species Amblyomma sculptum, 475 adults and 12 nymphs; 778 Amblyomma dubitatum, 727 adults and 51 nymphs; and seven larva clusters of the genus Amblyomma); and 588 (31.6%) from opossums (21 A. sculptum, one adult and 20 nymphs; 79 A. dubitatum, all nymphs; 15 Ixodes loricatus, 12 adults and three nymphs; 457 Amblyomma sp. larva clusters; 15 Ixodes sp. larva clusters; and one Argasidae larva cluster). Out of 201 DNA samples tested for the presence of Rickettsia spp. DNA using polymerase chain reaction (PCR) 12 showed amplification of a gtlA gene segment that was specific to Rickettsia bellii, a bacterium non-pathogenic to humans. As there has been a report showing serological evidence of infections caused by Rickettsia species of the spotted fever group (SFG) in capybaras and opossums in the park, including Rickettsia rickettsii, the etiological agent of Brazilian spotted fever, and considering the presence of A. sculptum ticks, which are aggressive to humans, as well as these vertebrate hosts, which are amplifiers of R. rickettsii, it is important to monitor the presence of SFG rickettsiae in the Sabiá Park, which is visited daily by thousands of people.


Assuntos
Didelphis , Ixodidae , Larva , Ninfa , Rickettsia , Animais , Brasil , Rickettsia/isolamento & purificação , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia , Larva/microbiologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ixodidae/microbiologia , Ixodidae/crescimento & desenvolvimento , Ixodidae/fisiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/epidemiologia , Feminino , Parques Recreativos , Amblyomma/microbiologia , Amblyomma/crescimento & desenvolvimento , Masculino , Roedores/parasitologia , Gambás/parasitologia
12.
Emerg Infect Dis ; 29(12): 2541-2545, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37987590

RESUMO

Opossums are considered resistant to rabies. Nonhematophagous bats are reservoirs of rabies in urban areas of South America. We analyzed bats and opossums tested for rabies during 2021 in a highly urbanized city in Brazil to understand spillover in an urban setting. Wildlife surveillance is necessary to prevent rabies in humans and domestic animals.


Assuntos
Didelphis , Raiva , Animais , Brasil/epidemiologia , Quirópteros , Gambás , Raiva/epidemiologia , Raiva/veterinária
13.
Mol Biol Evol ; 39(7)2022 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-35723968

RESUMO

Opossums in the tribe Didelphini are resistant to pit viper venoms and are hypothesized to be coevolving with venomous snakes. Specifically, a protein involved in blood clotting (von Willebrand factor [vWF] which is targeted by snake venom C-type lectins [CTLs]) has been found to undergo rapid adaptive evolution in Didelphini. Several unique amino acid changes in vWF could explain their resistance; however, experimental evidence that these changes disrupt binding to venom CTLs was lacking. Furthermore, without explicit testing of ancestral phenotypes to reveal the mode of evolution, the assertion that this system represents an example of coevolution rather than noncoevolutionary adaptation remains unsupported. Using expressed vWF proteins and purified venom CTLs, we quantified binding affinity for vWF proteins from all resistant taxa, their venom-sensitive relatives, and their ancestors. We show that CTL-resistant vWF is present in opossums outside clade Didelphini and likely across a wider swath of opossums (family Didelphidae) than previously thought. Ancestral reconstruction and in vitro testing of vWF phenotypes in a clade of rapidly evolving opossums reveal a pattern consistent with trench warfare coevolution between opossums and their venomous snake prey.


Assuntos
Venenos de Crotalídeos , Crotalinae , Animais , Venenos de Crotalídeos/genética , Gambás/metabolismo , Venenos de Serpentes/metabolismo , Serpentes/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
14.
Trop Med Int Health ; 28(9): 689-698, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37488635

RESUMO

OBJECTIVE: To analyse acute Chagas disease (CD) outbreaks through a qualitative systematic review and discuss the determinants for its prevention and control. METHODS: Review of studies in which clinical cases of oral transmission were confirmed by parasitological and/or serological tests that included an epidemiological investigation of sources of infection, vectors and reservoirs. RESULTS: Thirty-two outbreaks (1965-2022) were analysed. The main foods involved in oral transmission outbreaks are homemade fruit juices. Different species of vectors were identified. Reservoirs were mainly dogs, rodents and large American opossums (didelphids). CONCLUSION: Under a One Health approach, environmental changes are one of the factors responsible of the rise of oral transmission of CD. Entomological surveillance of vectors and control of the changes in wild and domestic reservoirs and reinforcement of hygiene measures around food in domestic and commercial sites are needed.


Assuntos
Doença de Chagas , Saúde Única , Trypanosoma cruzi , Animais , Cães , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Reservatórios de Doenças/veterinária , Genótipo , Gambás
15.
Med Vet Entomol ; 37(2): 396-406, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36632712

RESUMO

The present study, carried out in the municipality of Gentio do Ouro, Bahia, Brazil aimed to evaluate which wild mammals may be involved in the transmission of T. cruzi and which are the blood sources for triatomines collected in the study area. PCR analysis of 31 wild mammals captured revealed T. cruzi infection in 6.4% (2/31): one specimen of the opossum Didelphis albiventris (1/3) and one of the rodent Kerodon rupestris (1/5); despite being more frequent in the area, no specimen of the rodent Thrichomys sp. (0/23) was infected. A total of 169 triatomines were captured. The conclusive detection of food sources was possible only for Triatoma sherlocki Papa et al., 2002 (n = 56), with evidence for: K. rupestris (35.7%), Gallus (17.9%), D. albiventris (14.3%), Homo sapiens (14.3%), Tropidurus hispidus (7.1%), Leopardus geoffroyi (5.3%), Conepatus semistriatus (1.8%), Thrichomys inermis (1.8%) and Rattus norvegicus (1.8%). Triatomines of the species T. sherlocki showed food eclecticism, including feeding on humans, with some of them being captured at dwellings. These facts make this triatomine a potential link for the transmission of T. cruzi between wild and anthropic environments, highlighting a latent risk of the reemergence of Chagas disease outbreaks.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Humanos , Animais , Ratos , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Roedores , Gambás , Mamíferos
16.
Parasitol Res ; 122(5): 1151-1158, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36890298

RESUMO

Procyonids are reservoirs of many zoonotic infectious diseases, including tick-borne pathogens. The role of coatis (Nasua nasua) in the epidemiology of piroplasmids and Rickettsia has not been fully addressed in Brazil. To molecularly study these agents in coatis and associated ticks, animals were sampled in two urban areas in Midwestern Brazil. Blood (n = 163) and tick (n = 248) DNA samples were screened by PCR assays targeting the 18S rRNA and gltA genes of piroplasmids and Rickettsia spp., respectively. Positive samples were further molecularly tested targeting cox-1, cox-3, ß-tubulin, cytB, and hsp70 (piroplasmid) and ompA, ompB, and htrA 17-kDa (Rickettsia spp.) genes, sequenced and phylogenetically analyzed. All coatis' blood samples were negative for piroplasmids, whereas five pools of ticks (2%) were positive for two different sequences of Babesia spp.. The first from Amblyomma sculptum nymphs was close (i.e., ≥ 99% nucleotide identity) to a Babesia sp. previously found in capybaras (Hydrochoerus hydrochaeris); the second from Amblyomma dubitatum nymphs and Amblyomma spp. larvae was identical (100% nucleotide identity) to a Babesia sp. detected in opossums (Didelphis albiventris) and associated ticks. Four samples (0.8%) were positive by PCR to two different Rickettsia spp. sequences, being the first from Amblyomma sp. larva identical to Rickettsia belli and the second from A. dubitatum nymph identical to Rickettsia species from Spotted Fever Group (SFG). The detection of piroplasmids and SFG Rickettsia sp. highlights the importance of Amblyomma spp. in the maintenance of tick-borne agents in urban parks where humans and wild and domestic animals are living in sympatry.


Assuntos
Babesia , Ixodidae , Procyonidae , Rickettsia , Carrapatos , Humanos , Animais , Rickettsia/genética , Babesia/genética , Brasil/epidemiologia , Roedores , Gambás , Amblyomma , Ixodidae/microbiologia
17.
Int J Mol Sci ; 24(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068946

RESUMO

The p53 protein is a transcriptional regulatory factor and many of its functions require that it forms a tetrameric structure. Although the tetramerization domain of mammalian p53 proteins (p53TD) share significant sequence similarities, it was recently shown that the tree shrew p53TD is considerably more thermostable than the human p53TD. To determine whether other mammalian species display differences in this domain, we used biophysical, functional, and structural studies to compare the properties of the p53TDs from six mammalian model organisms (human, tree shrew, guinea pig, Chinese hamster, sheep, and opossum). The results indicate that the p53TD from the opossum and tree shrew are significantly more stable than the human p53TD, and there is a correlation between the thermostability of the p53TDs and their ability to activate transcription. Structural analysis of the tree shrew and opossum p53TDs indicated that amino acid substitutions within two distinct regions of their p53TDs can dramatically alter hydrophobic packing of the tetramer, and in particular substitutions at positions corresponding to F341 and Q354 of the human p53TD. Together, the results suggest that subtle changes in the sequence of the p53TD can dramatically alter the stability, and potentially lead to important changes in the functional activity, of the p53 protein.


Assuntos
Proteína Supressora de Tumor p53 , Animais , Cobaias , Humanos , Gambás/metabolismo , Ovinos , Proteína Supressora de Tumor p53/metabolismo , Tupaia/metabolismo
18.
J Helminthol ; 97: e58, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37476963

RESUMO

Marmosa constantiae is a species of marsupial restricted to the central portion of South America. In Brazil, it occurs in the northwestern region including five states of the Amazon, Cerrado, and Pantanal biomes. However, there is no study of the helminth fauna or helminth community structure for this marsupial. The aims of this study were to describe the species composition and to analyse the structure of the helminthic community of M. constantiae in an area of the Amazon Arc in Sinop, north of the state of Mato Grosso, Brazil. Parasites were searched in 53 specimens of this marsupial, among which 44 were infected with at least one helminth species. Parasitic helminths were counted and identified. Nine species were collected: seven nematodes, one cestode, and one acanthocephalan. The most abundant species were Gracilioxyuris agilisis, Travassostrongylus scheibelorum, Pterygodermatites sinopiensis, and Subulura eliseae. These species were the only dominant ones in the component community. No significant differences were observed in the abundance and prevalence of helminths between male and female hosts. Host body size significantly influenced helminth abundance in males. The pattern of community structure considering the infracommunities in this locality indicated more species replacement than species loss along the environmental gradient. This is the first study to report the helminth fauna and the helminth community structure of M. constantiae.


Assuntos
Helmintíase Animal , Helmintos , Marsupiais , Feminino , Masculino , Camundongos , Animais , Brasil/epidemiologia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Gambás/parasitologia
19.
Mol Biol Evol ; 38(3): 1060-1074, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33185661

RESUMO

Mammalian pregnancy evolved in the therian stem lineage, that is, before the common ancestor of marsupials and eutherian (placental) mammals. Ancestral therian pregnancy likely involved a brief phase of attachment between the fetal and maternal tissues followed by parturition-similar to the situation in most marsupials including the opossum. In all eutherians, however, embryo attachment is followed by implantation, allowing for a stable fetal-maternal interface and an extended gestation. Embryo attachment induces an attachment reaction in the uterus that is homologous to an inflammatory response. Here, we elucidate the evolutionary mechanism by which the ancestral inflammatory response was transformed into embryo implantation in the eutherian lineage. We performed a comparative uterine transcriptomic and immunohistochemical study of three eutherians, armadillo (Dasypus novemcinctus), hyrax (Procavia capensis), and rabbit (Oryctolagus cuniculus); and one marsupial, opossum (Monodelphis domestica). Our results suggest that in the eutherian lineage, the ancestral inflammatory response was domesticated by suppressing one of its modules detrimental to pregnancy, namely, neutrophil recruitment by cytokine IL17A. Further, we propose that this suppression was mediated by decidual stromal cells, a novel cell type in eutherian mammals. We tested a prediction of this model in vitro and showed that decidual stromal cells can suppress the production of IL17A from helper T cells. Together, these results provide a mechanistic understanding of early stages in the evolution of eutherian pregnancy.


Assuntos
Evolução Biológica , Implantação do Embrião , Eutérios/genética , Interleucina-17/metabolismo , Gambás/metabolismo , Útero/metabolismo , Animais , Decídua/citologia , Eutérios/embriologia , Feminino , Expressão Gênica , Modelos Biológicos , Infiltração de Neutrófilos , Coelhos , Células Estromais
20.
Ecol Appl ; 32(7): e2647, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35535608

RESUMO

To mitigate human-wildlife conflict it is imperative to know where and when conflict occurs. However, standard methods used to predict the occurrence of human-wildlife conflict often fail to recognize how a species distribution likely limits where and when conflict may happen. As such, methods that predict human-wildlife conflict could be improved if they could identify where conflict will occur relative to species' underlying distribution. To this end, we used an integrated species distribution model that combined presence-only wildlife complaints with data from a systematic camera trapping survey throughout Chicago, Illinois. This model draws upon both data sources to estimate a latent distribution of species; in addition, the model can estimate where conflict is most likely to occur within that distribution. We modeled the occupancy and conflict potential of coyote (Canis latrans), Virginia opossum (Didelphis virginiana), and raccoon (Procyon lotor) as a function of urban intensity, per capita income, and home vacancy rates throughout Chicago. Overall, the distribution of each species constrained the spatiotemporal patterns of conflict throughout the city of Chicago. Within each species distribution, we found that human-wildlife conflict was most likely to occur where humans and wildlife habitat overlap (e.g., featuring higher-than-average canopy cover and housing density). Furthermore, human-wildlife conflict was most likely to occur in high-income neighborhoods for Virginia opossum and raccoon, despite the fact that those two species have higher occupancy in low-income neighborhoods. As such, knowing where species are distributed can inform guidelines on where wildlife management should be focused, especially if it overlaps with human habitats. Finally, because this integrated model can incorporate data that have already been collected by wildlife managers or city officials, this approach could be used to develop stronger collaborations with wildlife management agencies and conduct applied research that will inform landscape-scale wildlife management.


Assuntos
Animais Selvagens , Guaxinins , Animais , Cidades , Ecossistema , Humanos , Gambás
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