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1.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34519348

RESUMO

Islands are insular environments that are negatively impacted by invasive species. In Hawai'i, at least 21 non-native bees have been documented to date, joining the diversity of >9,000 non-native and invasive species to the archipelago. The goal of this study is to describe the persistence, genetic diversity, and natural history of the most recently established bee to Hawai'i, Megachile policaris Say, 1831 (Hymenoptera: Megachilidae). Contemporary surveys identify that M. policaris is present on at least O'ahu, Maui, and Hawai'i Island, with the earliest detection of the species in 2017. Furthermore, repeated surveys and observations by community members support the hypothesis that M. policaris has been established on Hawai'i Island from 2017 to 2020. DNA sequenced fragments of the cytochrome oxidase I locus identify two distinct haplotypes on Hawai'i Island, suggesting that at least two founders have colonized the island. In their native range, M. policaris is documented to forage on at least 21 different plant families, which are represented in Hawai'i. Finally, ensemble species distribution models (SDMs) constructed with four bioclimatic variables and occurrence data from the native range of M. policaris predicts high habitat suitability on the leeward side of islands throughout the archipelago and at high elevation habitats. While many of the observations presented in our study fall within the predicted habitat suitability on Hawai'i, we also detected the M. policaris on the windward side of Hawai'i Island suggesting that the SDMs we constructed likely do not capture the bioclimatic niche flexibility of the species.


Assuntos
Abelhas , Espécies Introduzidas , Distribuição Animal , Animais , Abelhas/genética , Abelhas/fisiologia , Ecossistema , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Insetos , Haplótipos , Hawaii , Modelos Estatísticos , Polinização , Dinâmica Populacional
3.
Commun Biol ; 4(1): 853, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244609

RESUMO

Plant-herbivore interactions promote the generation and maintenance of both plant and herbivore biodiversity. The antagonistic interactions between plants and herbivores lead to host race formation: the evolution of herbivore types specializing on different plant species, with restricted gene flow between them. Understanding how ecological specialization promotes host race formation usually depends on artificial approaches, using laboratory experiments on populations associated with agricultural crops. However, evidence on how host races are formed and maintained in a natural setting remains scarce. Here, we take a multidisciplinary approach to understand whether populations of the generalist spider mite Tetranychus urticae form host races in nature. We demonstrate that a host race co-occurs among generalist conspecifics in the dune ecosystem of The Netherlands. Extensive field sampling and genotyping of individuals over three consecutive years showed a clear pattern of host associations. Genome-wide differences between the host race and generalist conspecifics were found using a dense set of SNPs on field-derived iso-female lines and previously sequenced genomes of T. urticae. Hybridization between lines of the host race and sympatric generalist lines is restricted by post-zygotic breakdown, and selection negatively impacts the survival of generalists on the native host of the host race. Our description of a host race among conspecifics with a larger diet breadth shows how ecological and reproductive isolation aid in maintaining intra-specific variation in sympatry, despite the opportunity for homogenization through gene flow. Our findings highlight the importance of explicitly considering the spatial and temporal scale on which plant-herbivore interactions occur in order to identify herbivore populations associated with different plant species in nature. This system can be used to study the underlying genetic architecture and mechanisms that facilitate the use of a large range of host plant taxa by extreme generalist herbivores. In addition, it offers the chance to investigate the prevalence and mechanisms of ecological specialization in nature.


Assuntos
Adaptação Fisiológica/genética , Produtos Agrícolas/genética , Fluxo Gênico/genética , Variação Genética , Tetranychidae/genética , Animais , Proteínas de Artrópodes/classificação , Proteínas de Artrópodes/genética , Produtos Agrícolas/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Especiação Genética , Herbivoria/classificação , Herbivoria/genética , Interações Hospedeiro-Parasita/genética , Países Baixos , Filogenia , Isolamento Reprodutivo , Especificidade da Espécie , Simpatria , Tetranychidae/classificação
4.
J Cardiothorac Surg ; 16(1): 167, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099002

RESUMO

BACKGROUND: Cystic echinococcosis (CE)/hydatidosis is an important neglected parasitic zoonotic disease caused by the metacestode of Echinococcus granulosus s.l. The present study was designed to identify the pulmonary CE species/genotypes in isolated human underwent to surgery in our center in Southern Iran. METHODS: The study population of this study were all patients in Fars province who were admitted to Namazi Hospitals for pulmonary hydatid cyst surgery. Thoracic surgery was performed in the thoracic ward and the cyst/s was removed by open surgery via posterolateral or lateral thoracotomy. DNA was extracted from the germinal layer or the protoscoleces. PCR technique was performed using the cytochrome C oxidase subunit1 (cox1) gene, and the products were sequenced. RESULTS: A total of 32 pulmonary hydatid cyst samples were collected from 9 (28%) female and 23 (72%) male aged from 4 to 74 years old. A total of 18(56%) cyst/s were in the left lobe and 14 (44%) cysts in the right lobe. Sequence analysis of the cysts showed that 24 samples (75%) were E. granulosus s.s (G1-G3) genotype and 8 (25%) were E. canadensis (G6/G7) genotype. CONCLUSION: E.granulosus s.s genotype was the most prevalent genotype followed by E. canadensis (G6/G7) genotype. There was no significant statistical correlation between cysts' size, location, genotype strain, and patients' age and gender.


Assuntos
DNA de Helmintos/análise , Equinococose Pulmonar/parasitologia , Echinococcus granulosus/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Genótipo , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Equinococose Pulmonar/diagnóstico , Echinococcus granulosus/classificação , Echinococcus granulosus/isolamento & purificação , Feminino , Marcadores Genéticos , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Análise de Sequência , Análise de Sequência de DNA , Adulto Jovem
5.
Mol Biochem Parasitol ; 244: 111391, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34144085

RESUMO

The Leishmania LACK antigen is a ribosome-associated protein that facilitates expression of mitochondrial cytochrome c oxidase subunit IV (LmCOX4) to support parasite mitochondrial fitness and virulence within the vertebrate host. To further examine the relationship between LACK, its putative ribosome binding motif and LmCOX4, we compared the kinetics of LmCOX4 expression following temperature elevation in wildtype LACK (LACK WT) and LACK-putative ribosome-binding mutant (LACKDDE) L. major. We found that, after initial exposure to mammalian temperature, LmCOX4 levels became undetectable in LACKDDE L. major and also, surprisingly, in wild type (WT) control strains. Upon sustained exposure to mammalian temperature, LmCOX4 expression returned in WT control strains only. The initial loss of LmCOX4 in WT L. major was substantially reversed by treatment with the proteasome inhibitor MG132. Our findings indicate that initial loss of LmCOX4 under mammalian conditions is dependent upon proteasome degradation and LmCOX4 re-expression is dependent upon LACK possessing a WT putative ribosome binding motif.


Assuntos
Antígenos de Protozoários/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Leishmania major/genética , Mitocôndrias/genética , Proteínas de Protozoários/genética , Ribossomos/genética , Motivos de Aminoácidos , Animais , Antígenos de Protozoários/metabolismo , Sítios de Ligação , Temperatura Corporal , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica , Leishmania major/metabolismo , Leupeptinas/farmacologia , Mamíferos/parasitologia , Mitocôndrias/metabolismo , Mutação , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Ligação Proteica , Proteólise , Proteínas de Protozoários/metabolismo , Ribossomos/metabolismo
6.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065857

RESUMO

The mitochondria are essential for normal cell functioning. Changes in mitochondrial DNA (mtDNA) may affect the occurrence of some chronic diseases and cancer. This process is complex and not entirely understood. The assignment to a particular mitochondrial haplogroup may be a factor that either contributes to cancer development or reduces its likelihood. Mutations in mtDNA occurring via an increase in reactive oxygen species may favour the occurrence of further changes both in mitochondrial and nuclear DNA. Mitochondrial DNA mutations in postmitotic cells are not inherited, but may play a role both in initiation and progression of cancer. One of the first discovered polymorphisms associated with cancer was in the gene NADH-ubiquinone oxidoreductase chain 3 (mt-ND3) and it was typical of haplogroup N. In prostate cancer, these mutations and polymorphisms involve a gene encoding subunit I of respiratory complex IV cytochrome c oxidase subunit 1 gene (COI). At present, a growing number of studies also address the impact of mtDNA polymorphisms on prognosis in cancer patients. Some of the mitochondrial DNA polymorphisms occur in both chronic disease and cancer, for instance polymorphism G5913A characteristic of prostate cancer and hypertension.


Assuntos
DNA Mitocondrial/genética , Mitocôndrias/genética , Neoplasias/genética , Progressão da Doença , Complexo I de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Predisposição Genética para Doença , Humanos , Mutação , Neoplasias/metabolismo , Polimorfismo Genético , Espécies Reativas de Oxigênio/metabolismo
7.
Zootaxa ; 4980(3): 490520, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34186968

RESUMO

Three new species of the genus Heteromysis S.I. Smith, 1873 (tribus Heteromysini), are described from a rich stock of mysids obtained on request from the international community of professional aquarium keepers. The 18S rDNA and COI sequences of the three species were distinct from each other and also from other sequences published in DNA databases. Heteromysis (Olivemysis) schoenbrunnensis sp. nov. is morphologically characterized within the subgenus Olivemysis based on the structure of the first and second antennae, male pleopods, uropods, and telson. Heteromysis (Heteromysis) gulfarii sp. nov. is outstanding within the subgenus Heteromysis by sexually dimorphic modified setae on the antennular trunk. These setae are non-dimorphic in the very similar Heteromysis (Heteromysis) korntalensis sp. nov. Both species H. gulfarii and to a lesser degree also H. korntalensis show modified eyes, subquadrate in dorsal view, eyestalks anteriorly tapering in lateral view; small, well-developed cornea implanted laterally on modified eyestalk. Apart from eye structure H. gulfarii and H. korntalensis clearly fall morphologically within the nominotypical subgenus Heteromysis.


Assuntos
Crustáceos , Animais , Animais de Zoológico , Recifes de Corais , Crustáceos/anatomia & histologia , Crustáceos/classificação , Crustáceos/genética , DNA Ribossômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Europa (Continente) , Florida , Masculino , RNA Ribossômico 18S/genética , Especificidade da Espécie
8.
Zootaxa ; 4981(3): 593600, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34186704

RESUMO

A new genus (Arboramima Zong, Qin He gen. nov.) with a new species (Arboramima cattusis Zong, Qin He sp. nov.) is reported from Guangxi, China. The morphology of the new genus and species are provided. Samples of Aemodogryllinae species were selected for the reconstruction of phylogenetic tree based on mitochondrial COI fragment. The results supported the validation of the new genus. The type specimens are deposited in Museum of Biology, East China Normal University (ECNU).


Assuntos
Ortópteros , Filogenia , Distribuição Animal , Animais , China , Complexo IV da Cadeia de Transporte de Elétrons/genética , Masculino , Ortópteros/anatomia & histologia , Ortópteros/classificação , Ortópteros/genética , Especificidade da Espécie
9.
Am J Physiol Endocrinol Metab ; 321(1): E47-E62, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33969705

RESUMO

Myoglobin (Mb) regulates O2 bioavailability in muscle and heart as the partial pressure of O2 (Po2) drops with increased tissue workload. Globin proteins also modulate cellular NO pools, "scavenging" NO at higher Po2 and converting NO2- to NO as Po2 falls. Myoglobin binding of fatty acids may also signal a role in fat metabolism. Interestingly, Mb is expressed in brown adipose tissue (BAT), but its function is unknown. Herein, we present a new conceptual model that proposes links between BAT thermogenic activation, concurrently reduced Po2, and NO pools regulated by deoxy/oxy-globin toggling and xanthine oxidoreductase (XOR). We describe the effect of Mb knockout (Mb-/-) on BAT phenotype [lipid droplets, mitochondrial markers uncoupling protein 1 (UCP1) and cytochrome C oxidase 4 (Cox4), transcriptomics] in male and female mice fed a high-fat diet (HFD, 45% of energy, ∼13 wk), and examine Mb expression during brown adipocyte differentiation. Interscapular BAT weights did not differ by genotype, but there was a higher prevalence of mid-large sized droplets in Mb-/-. COX4 protein expression was significantly reduced in Mb-/- BAT, and a suite of metabolic/NO/stress/hypoxia transcripts were lower. All of these Mb-/--associated differences were most apparent in females. The new conceptual model, and results derived from Mb-/- mice, suggest a role for Mb in BAT metabolic regulation, in part through sexually dimorphic systems and NO signaling. This possibility requires further validation in light of significant mouse-to-mouse variability of BAT Mb mRNA and protein abundances in wild-type mice and lower expression relative to muscle and heart.NEW & NOTEWORTHY Myoglobin confers the distinct red color to muscle and heart, serving as an oxygen-binding protein in oxidative fibers. Less attention has been paid to brown fat, a thermogenic tissue that also expresses myoglobin. In a mouse knockout model lacking myoglobin, brown fat had larger fat droplets and lower markers of mitochondrial oxidative metabolism, especially in females. Gene expression patterns suggest a role for myoglobin as an oxygen/nitric oxide-sensor that regulates cellular metabolic and signaling pathways.


Assuntos
Tecido Adiposo Marrom/fisiologia , Mioglobina/fisiologia , Adipócitos Marrons/fisiologia , Tecido Adiposo Marrom/química , Tecido Adiposo Marrom/ultraestrutura , Animais , Diferenciação Celular , Células Cultivadas , Dieta Hiperlipídica , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Expressão Gênica , Lipídeos/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/fisiologia , Mioglobina/deficiência , Mioglobina/genética , Óxido Nítrico/metabolismo , Oxigênio/metabolismo , RNA Mensageiro/análise
10.
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
11.
PLoS One ; 16(4): e0249227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33793620

RESUMO

Bacteria play an integral role in shaping plant growth and development. However, the genetic factors that facilitate plant-bacteria interactions remain largely unknown. Here, we demonstrated the importance of two bacterial genetic factors that facilitate the interactions between plant-growth-promoting (PGP) bacteria in the genus Caulobacter and the host plant Arabidopsis. Using homologous recombination, we disrupted the cytochrome ubiquinol oxidase (cyo) operon in both C. vibrioides CB13 and C. segnis TK0059 by knocking out the expression of cyoB (critical subunit of the cyo operon) and showed that the mutant strains were unable to enhance the growth of Arabidopsis. In addition, disruption of the cyo operon, metabolomic reconstructions, and pH measurements suggested that both elevated cyoB expression and acid production by strain CB13 contribute to the previously observed inhibition of Arabidopsis seed germination. We also showed that the crescent shape of the PGP bacterial strain C. crescentus CB15 contributes to its ability to enhance plant growth. Thus, we have identified specific genetic factors that explain how select Caulobacter strains interact with Arabidopsis plants.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Caulobacter/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Arabidopsis/anatomia & histologia , Arabidopsis/microbiologia , Proteínas de Bactérias/metabolismo , Caulobacter/classificação , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Expressão Gênica , Germinação , Recombinação Homóloga , Concentração de Íons de Hidrogênio , Filogenia , Subunidades Proteicas/deficiência , Subunidades Proteicas/genética , Espécies Reativas de Oxigênio/metabolismo
12.
Nat Commun ; 12(1): 2130, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837217

RESUMO

Mito-SEPs are small open reading frame-encoded peptides that localize to the mitochondria to regulate metabolism. Motivated by an intriguing negative association between mito-SEPs and inflammation, here we screen for mito-SEPs that modify inflammatory outcomes and report a mito-SEP named "Modulator of cytochrome C oxidase during Inflammation" (MOCCI) that is upregulated during inflammation and infection to promote host-protective resolution. MOCCI, a paralog of the NDUFA4 subunit of cytochrome C oxidase (Complex IV), replaces NDUFA4 in Complex IV during inflammation to lower mitochondrial membrane potential and reduce ROS production, leading to cyto-protection and dampened immune response. The MOCCI transcript also generates miR-147b, which targets the NDUFA4 mRNA with similar immune dampening effects as MOCCI, but simultaneously enhances RIG-I/MDA-5-mediated viral immunity. Our work uncovers a dual-component pleiotropic regulation of host inflammation and immunity by MOCCI (C15ORF48) for safeguarding the host during infection and inflammation.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Pleiotropia Genética/imunologia , Inflamação/imunologia , MicroRNAs/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Linhagem Celular , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Técnicas de Inativação de Genes , Humanos , Inflamação/genética , Inflamação/patologia , Potencial da Membrana Mitocondrial/imunologia , MicroRNAs/genética , Mitocôndrias/imunologia , Mitocôndrias/patologia , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/imunologia
13.
Acta Trop ; 219: 105913, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33831346

RESUMO

Biting midges in the genus Culicoides (Diptera; Ceratopogonidae) are vectors of pathogens that can cause diseases of major economic importance in humans and animals. Identifying host ranges of these biting midges might aid in understanding the complex epidemiology of such diseases, often involving reservoir hosts and multiple species. In this study, we aim to identify bloodmeal origin from engorged female Culicoides biting midges. All bloodfed females were opportunistically collected as part of an ongoing surveillance programme using Onderstepoort light traps in two provinces in South Africa. DNA of individuals was extracted and subjected to PCR targeting the cytochrome B (CytB) gene region of mammals and avians as well as cytochrome oxidase I (COI) for species identification. In total, 21 new reference barcodes were generated for C. bedfordi, C imicola, C. leucosticus, C. magnus, and C. pycnostictus. Seventy-four blood meals were identified, originating from 12 mammal and three avian species. COI sequence data performed well for species delimitation and 54 Culicoides specimens were identified with C. imicola the predominant species identified (41.8%). Generally, Culicoides species feed on a variety of hosts and host availability might be an important factor when selecting a host. Culicoides species thus appear to be opportunistic feeders rather than specialists. This implicates Culicoides as transfer vectors and demonstrates possible transmission routes of arboviruses and other pathogens from wildlife onwards to domestic animals and humans.


Assuntos
Sangue/parasitologia , Ceratopogonidae/classificação , Citocromos b/genética , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Animais , Arbovírus/fisiologia , Ceratopogonidae/genética , Feminino , Especificidade de Hospedeiro , Humanos , Insetos Vetores/genética , África do Sul
14.
Zootaxa ; 4964(1): zootaxa.4964.1.6, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33903531

RESUMO

Oxynoemacheilus sarus, new species, is described from the lower Ceyhan and Seyhan drainages in southern Anatolia. It is distinguished from other Oxynoemacheilus species in Cilicia (including the Göksu, Seyhan and Ceyhan drainages) by possession of a series of irregularly shaped midlateral blotches, 3-5 dark-brown bands on the caudal fin, a complete lateral line, a forked caudal fin (shortest middle caudal-fin ray is 56-70% of longest ray of the upper caudal-fin lobe), the caudal peduncle depth 1.4-1.8 times in its length, and a suborbital groove in male individuals. The new species occurs in sympatry with superficially similar O. seyhanicola and O. evreni, and is distinguished by colour pattern as well as morphometric and molecular characters. Molecular data suggest that the closest relatives to the new species in our dataset are O. euphraticus and O. shehabi, which is characterised by a minimum K2P distance of 3.6% and 3.8%, respectively, in the COI mtDNA barcode region.


Assuntos
Cipriniformes , Animais , Cipriniformes/classificação , Cipriniformes/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Peixes/genética , Masculino , Pigmentação , Rios , Especificidade da Espécie , Simpatria , Turquia
15.
Zootaxa ; 4963(3): zootaxa.4963.3.2, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33903539

RESUMO

Haplaxius is a large genus of cixiid planthoppers that is widespread in the New World and economically important due to the role of H. crudus in transmitting palm lethal decline phytoplasmas. A new species of Haplaxius, here described as Haplaxius pocococo sp. n., was discovered during survey work on palms in north-central Costa Rica. Placement in Haplaxius is supported by sequence analysis of the COI and 18S genes relative to congeners and by morphological characters.


Assuntos
Cocos , Hemípteros , Insetos Vetores , Animais , Cocos/parasitologia , Costa Rica , Complexo IV da Cadeia de Transporte de Elétrons/genética , Hemípteros/anatomia & histologia , Hemípteros/classificação , Hemípteros/genética , Insetos Vetores/anatomia & histologia , Insetos Vetores/classificação , Insetos Vetores/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie
16.
Mol Ecol Resour ; 21(6): 2109-2124, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33892518

RESUMO

The Maroni is one of the most speciose basins of the Guianas and hosts a megadiverse freshwater fish community. Although taxonomic references based on morphological identification exist for both the Surinamese and Guianese parts of the basin, there are still taxonomic uncertainties concerning the status of several species. We used COI sequences of 1284 fish in conjunction with morphological and biogeographical evidence to assist with species delineation and discovery in order to validate and standardize the current taxonomy. This resulted in a final DNA barcode data set of 199 fish species (125 genera, 36 families and eight orders; 68.86% of strictly freshwater fishes from the basin), among which 25 are new putative candidate species flagged as requiring taxonomic update. DNA barcoding delineation through Barcode Index Numbers (BINs) revealed further cryptic diversity (230 BINs in total). To explore global genetic patterns across the basin, genetic divergence landscapes were computed for 128 species, showing a global trend of high genetic divergence between the Surinamese southwest (Tapanahony and Paloemeu), the Guianese southeast (Marouini, Litany, Tampok, etc.), and the river outlet in the north. This could be explained by lower levels of connectivity between these three main areas and/or the exchange of individuals between these areas and the neighbouring basins. A new method of ordination of genetic landscapes successfully assigned species into cluster groups based on their respective pattern of genetic divergence across the Maroni Basin: genetically homogeneous species were effectively discriminated from species showing high spatial genetic fragmentation and possible lower capacity for dispersal.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons , Peixes/classificação , Animais , Análise por Conglomerados , Complexo IV da Cadeia de Transporte de Elétrons/genética , Peixes/genética , Guiana Francesa , Água Doce , Variação Genética , Filogenia , Suriname
17.
J Parasitol ; 107(2): 289-294, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33844840

RESUMO

Members of the flea family Pulicidae have been the focus of many studies due to their significance as diseases vectors of medical and veterinary importance and their cosmopolitan distribution. They often exhibit variation in morphological features that can make correct species identification and management challenging. This may also apply to Xenopsylla brasiliensis (Baker, 1904), an important plague vector. In the current study, we aimed to provide genetic tools for reliable species identification using a DNA barcoding approach. A total of 73 flea specimens was collected from a native host (Namaqua rock mouse, Micaelamys namaquensis) in South Africa and identified morphologically. In addition, we took measurements of 7 morphological characteristics. Subsequently, we successfully generated barcodes of the mitochondrial cytochrome c oxidase subunit I (COI) gene for X. brasiliensis. We validated this approach by comparing our data to COI sequences from Rwandan X. brasiliensis. While sequences from both regions suggested a close relationship between the 2 X. brasiliensis populations, both haplotype and nucleotide diversity were substantially larger for the South African specimens. This may be attributed to human-assisted spread, differences in habitat, and/or host species sampled and merits further study in the future.


Assuntos
Insetos Vetores/anatomia & histologia , Insetos Vetores/genética , Peste/transmissão , Xenopsylla/anatomia & histologia , Xenopsylla/genética , Animais , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Infestações por Pulgas/parasitologia , Infestações por Pulgas/veterinária , Variação Genética , Haplótipos , Masculino , Mitocôndrias/enzimologia , Murinae/parasitologia , África do Sul
18.
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
19.
Biochem Biophys Res Commun ; 556: 134-141, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33839409

RESUMO

Oxidative stress is a deteriorating factor for pancreatic ß-cells under chronic hyperglycemia in diabetes. However, the molecular mechanism underlying the increase in oxidative stress in ß-cells under diabetic conditions remains unclear. We demonstrated previously that the selective alleviation of glucotoxicity ameliorated the downregulation of several ß-cell factors, including Cox6a2. Cox6a2 encodes a subunit of the respiratory chain complex IV in mitochondria. In this study, we analyzed the role of Cox6a2 in pancreatic ß-cell function and its pathophysiological significance in diabetes mellitus. Cox6a2-knockdown experiments in MIN6-CB4 cells indicated an increased production of reactive oxygen species as detected by CellROX Deep Red reagent using flow cytometry. In systemic Cox6a2-knockout mice, impaired glucose tolerance was observed under a high-fat high-sucrose diet. However, insulin resistance was reduced when compared with control littermates. This indicates a relative insufficiency of ß-cell function. To examine the transcriptional regulation of Cox6a2, ATAC-seq with islet DNA was performed and an open-chromatin area within the Cox6a2 enhancer region was detected. Reporter gene analysis using this area revealed that MafA directly regulates Cox6a2 expression. These findings suggest that the decreased expression of Cox6a2 increases the levels of reactive oxygen species and that Mafa is associated with decreased Cox6a2 expression under glucotoxic conditions.


Assuntos
Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Proteínas Musculares/deficiência , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Intolerância à Glucose/genética , Células HEK293 , Humanos , Insulina/metabolismo , Resistência à Insulina/genética , Fatores de Transcrição Maf Maior/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , Estresse Oxidativo , Transcrição Genética
20.
Nat Chem Biol ; 17(6): 703-710, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33723432

RESUMO

The protein complexes of the mitochondrial electron transport chain exist in isolation and in higher order assemblies termed supercomplexes (SCs) or respirasomes (SC I+III2+IV). The association of complexes I, III and IV into the respirasome is regulated by unknown mechanisms. Here, we designed a nanoluciferase complementation reporter for complex III and IV proximity to determine in vivo respirasome levels. In a chemical screen, we found that inhibitors of the de novo pyrimidine synthesis enzyme dihydroorotate dehydrogenase (DHODH) potently increased respirasome assembly and activity. By-passing DHODH inhibition via uridine supplementation decreases SC assembly by altering mitochondrial phospholipid composition, specifically elevated peroxisomal-derived ether phospholipids. Cell growth rates upon DHODH inhibition depend on ether lipid synthesis and SC assembly. These data reveal that nucleotide pools signal to peroxisomes to modulate synthesis and transport of ether phospholipids to mitochondria for SC assembly, which are necessary for optimal cell growth in conditions of nucleotide limitation.


Assuntos
Transporte de Elétrons , Nucleotídeos/química , Peroxissomos/química , Fosfolipídeos/química , Transporte de Elétrons/genética , Complexo III da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lipídeos/biossíntese , Metabolômica , Mitocôndrias/metabolismo , Estrutura Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Consumo de Oxigênio , Éteres Fosfolipídicos , Uridina/metabolismo
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