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1.
Zootaxa ; 4970(1): 119130, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34186906

RESUMO

A new marine Sargassum-boring species of Limnoria (Limnoriidae) is described on the basis of specimens obtained at Kamogawa-shi, Chiba Prefecture, Japan. Limnoria aspera sp. nov. shares a reduced mandibular palp to a seta, algal-feeding, and the clavate shaped epipod of the maxilliped with the other species of non-mandibular-palp group. L. aspera sp. nov. differs morphologically from the congeneric species by secondary unguis of pereopods and unique carinae of pleonite 5 and pleotelson. We describe the sequences of the mitochondrial COI gene and the nuclear 28S rDNA gene. L. aspera sp. nov. differs by 14.218.0% in p-distance based on COI sequences from other Japanese species, L. furca and L. nagatai.


Assuntos
Isópodes/anatomia & histologia , Isópodes/classificação , Sargassum , Animais , DNA Ribossômico/genética , Genes Mitocondriais , Japão
2.
Parasitol Res ; 120(7): 2493-2503, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34115215

RESUMO

Recent anecdotal reports from seafood processors in eastern Australia have described an increased occurrence of post-mortem myoliquefaction ('jellymeat') in broadbill swordfish Xiphias gladius, and macroscopic cysts throughout the musculature of yellowfin tuna Thunnus albacares. A genus of parasitic cnidarians, Kudoa (Myxosporea, Multivalvulida), species of which are known to occur in economically important wild-caught fish species globally, can cause similar quality-deterioration issues. However, Kudoa sp. epizootiology within commercially harvested, high-value fish caught within Australia is poorly understood, despite the parasite's economic importance. To determine the causative agent responsible for the observed quality deterioration in swordfish and yellowfin tuna, muscle-tissue samples from seafood processors in Mooloolaba, Australia, collected from October 2019-February 2020, were examined for parasitic infection. Kudoid myxospores were identified from both hosts and were subquadrate in shape, with four equal-sized polar capsules. The SSU rDNA sequences from both fish shared > 99% identity to Kudoa species. Kudoa musculoliquefaciens was isolated from 87.1% of swordfish sampled, suggesting that it is a widespread parasite in swordfish from the southwest Pacific Ocean. This study provides the first molecular and morphological characterisation of Kudoa thunni in yellowfin tuna and K. musculoliquefaciens in swordfish harvested from the waters of eastern Australia, expanding the geographical distribution of K. thunni and K. musculoliquefaciens to include the Coral and Tasman Seas. We demonstrate that not all infected swordfish progress to jellymeat, show the usefulness of molecular tools for reliably identifying infection by Kudoa spp., and add to the overall knowledge of kudoid epizootiology in wild-caught fish.


Assuntos
Peixes/parasitologia , Myxozoa/classificação , Atum/parasitologia , Animais , Austrália , DNA Ribossômico/genética , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Músculos/parasitologia , Myxozoa/anatomia & histologia , Myxozoa/genética , Oceano Pacífico , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Alimentos Marinhos/parasitologia , Especificidade da Espécie
3.
Parasitol Res ; 120(7): 2505-2521, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34170388

RESUMO

The present paper describes Filisoma argusum n. sp. (Cavisomatidae), an acanthocephalan parasite infecting the intestine of the spotted scat, Scatophagus argus (Linnaeus, 1766), in the south-west coast of India. The prevalence is 18% (mean intensity: 1.61 and abundance: 1-4 worms/host). Filisoma argusum n. sp. is morphologically characterized by a creamy-white, cylindrical, elongate, aspinose, and robust trunk; a collar-like neck; and a cylindrical proboscis with 18-20 longitudinal rows of hooks, with 19-22 hooks/row. Proboscis receptacle long, double-walled. Lemnisci digitiform, equal, longer than proboscis receptacle. Females 79.14 ± 33.69 × 0.593 ± 0.19 mm; males 32.62 ± 2.98 × 0.46 ± 0.071 mm. Males with four cement glands; bulbous muscular copulatory bursa with six digitiform rays. SEM studies revealed smooth hooks, sensory pits, and epidermal micropores. Histopathological changes at the site of parasite attachment included inflammation, hemorrhage, sloughing of epithelium, and detachment of mucosal layer of the intestine. In molecular and phylogenetic analyses, the parasite occupied an independent position within the Cavisomatidae clade with high bootstrap values for both ITS1-5.8S and ITS2, and mt-CO1 regions. Considering the morphologic and morphometric differences with previously described species of Filisoma along with its phylogenetic positioning, the present acanthocephalan is treated as a new species and the name Filisoma argusum n. sp. is proposed.


Assuntos
Acantocéfalos/classificação , Peixes/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/genética , Animais , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Índia , Intestinos/parasitologia , Masculino , Filogenia , Especificidade da Espécie
4.
Eur J Protistol ; 79: 125796, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33975057

RESUMO

Blastocystis is a common enteric protist that inhabits the gastrointestinal tract of approximately 1 billion people worldwide. In this study, a total of 1,070 patients from two hospitals in Zhengzhou, Central China were enrolled to know molecular characteristics of Blastocystis sp. The microorganism was identified and subtyped with a PCR amplification and sequencing of the small subunit ribosomal deoxyribonucleic acid (SSU-rDNA). The overall minimum prevalence of Blastocystis sp. in participants was 3.1% (33/1070). Although there were no significant differences on Blastocystis sp. infections among study sites, age groups, and gender, the higher infection was observed in the patients with gastrointestinal diseases (8.8%, 15/170). Sequence analysis of the 33 isolates revealed three known subtypes, such as ST1 (n = 7), ST3 (n = 23), and ST7 (n = 3). Among them, ST3 was the dominant subtype being detected in 23 isolates (69.7%), followed by ST1 (21.2%, 7/33) and ST7 (9.1%, 3/33). The phylogenetic analysis demonstrated that three subtypes (ST1, ST3 and ST7) were clustered with their reference sequences with good bootstrap support. The subtype determination of Blastocystis sp. isolates by the phylogenetic analysis was well supported by online platform. The present study provides the first molecular report of Blastocystis sp. infections in hospital patients in Central China.


Assuntos
Infecções por Blastocystis/parasitologia , Blastocystis/classificação , Blastocystis/genética , Blastocystis/isolamento & purificação , Infecções por Blastocystis/epidemiologia , China/epidemiologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Tipagem Molecular , Filogenia , Prevalência , Especificidade da Espécie
5.
Eur J Protistol ; 79: 125797, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33979712

RESUMO

During daily monitoring in Yongho Bay off Busan, Korea in 2019, an isolate of the dinoflagellate genus Heterocapsa was established in clonal culture. Light and electron microscopic examination revealed that the isolate was ellipsoid in shape, exhibiting a thecal plate arrangement (Po, cp, X, 5', 3a, 7″, 6c, 5s, 5‴, 2'''') consistent with most other Heterocapsa species. A large, elongated nucleus was positioned on the left side of the cell, a single reticulate chloroplast was located peripherally, and a single, starch-sheathed, spherical pyrenoid was present in the episome or near the cingulum. Morphologically, the isolate most closely resembles H. circularisquama and H. illdefina. Transmission electron microscopic examination of whole mounts revealed that the isolate had two body scale types, one of which was a complex, three-dimensional, fine structure distinct from other Heterocapsa species, whereas the other simpler type was structurally similar to the scales of H. horiguchii. Molecular phylogeny based on rRNA sequences revealed that the isolate was distantly related to morphologically similar species, but formed a sister lineage to H. horiguchii, a species characterized by a similar body scale morphology. Based on morphological, ultrastructural, and molecular data, we proposed it as a new species, Heterocapsa busanensis sp. nov.


Assuntos
Dinoflagelados/classificação , DNA Ribossômico/genética , Dinoflagelados/ultraestrutura , Microscopia Eletrônica de Transmissão , Filogenia , República da Coreia , Água do Mar/parasitologia , Especificidade da Espécie
6.
Nucleic Acids Res ; 49(8): 4586-4598, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33836082

RESUMO

The nucleolus is the site of ribosome biosynthesis encompassing the ribosomal DNA (rDNA) locus in a phase separated state within the nucleus. In budding yeast, we find the rDNA locus and Cdc14, a protein phosphatase that co-localizes with the rDNA, behave like a condensate formed by polymer-polymer phase separation, while ribonucleoproteins behave like a condensate formed by liquid-liquid phase separation. The compaction of the rDNA and Cdc14's nucleolar distribution are dependent on the concentration of DNA cross-linkers. In contrast, ribonucleoprotein nucleolar distribution is independent of the concentration of DNA cross-linkers and resembles droplets in vivo upon replacement of the endogenous rDNA locus with high-copy plasmids. When ribosomal RNA is transcribed from the plasmids by Pol II, the rDNA-binding proteins and ribonucleoprotein signals are weakly correlated, but upon repression of transcription, ribonucleoproteins form a single, stable droplet that excludes rDNA-binding proteins from its center. Degradation of RNA-DNA hybrid structures, known as R-loops, by overexpression of RNase H1 results in the physical exclusion of the rDNA locus from the nucleolar center. Thus, the rDNA locus is a polymer-polymer phase separated condensate that relies on transcription and physical contact with RNA transcripts to remain encapsulated within the nucleolus.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular , Nucléolo Celular/metabolismo , DNA Ribossômico/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Estruturas R-Loop , RNA Polimerase I/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Nucléolo Celular/genética , Ensaios Clínicos Fase I como Assunto , DNA Ribossômico/genética , Fase G1/efeitos dos fármacos , Fase G1/genética , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Hidroliases/metabolismo , Cinética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Polímeros/química , Polímeros/metabolismo , Proteínas Tirosina Fosfatases/genética , RNA Polimerase I/genética , Ribonuclease H/genética , Ribonuclease H/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Regulação para Cima , Água/química , Água/metabolismo
7.
Parasitol Res ; 120(6): 1965-1977, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33851247

RESUMO

Procamallanus is a species-rich genus of parasitic nematodes of marine, brackish, and freshwater fishes, occurring also occasionally in amphibians and reptiles. In the Neotropical region, this genus is highly diverse, with species described from a wide range of fish families. In this study, we reassess the taxonomic status of Procamallanus rebecae with molecular and morphological data and describe a new species endemic to Nicaragua and Costa Rica. We analyzed all Procamallanus isolated from fish from the Nicaraguan lakes and some rivers in Costa Rica after an exhaustive analysis of their freshwater fish endoparasite fauna. Procamallanus rebecae is a host-specific parasite of Middle American cichlids, previously reported in southern Mexico, Nicaragua, and Costa Rica. We therefore compared these Central American specimens with individuals of P. rebecae collected in cichlids from southeastern Mexico using two genomic regions (28S rDNA and mitochondrial cytochrome oxidase subunit 1, COI). We found high levels of sequence divergence between Procamallanus from the two geographical regions, with up to 9.8 and 10.5% for both genetic markers, respectively. We also analyzed their morphology and found conspicuous differences in the shape of the mouth and the structure of the female cauda. We therefore describe the specimens of Procamallanus from Central American cichlids as a new species. Both Procamallanus species occur in different cichlid species and are allopatrically distributed. The host specificity and ancient association patterns between cichlids and Procamallanus and the jointly colonization of both hosts and parasites during their northern dispersal from South America are briefly discussed.


Assuntos
Ciclídeos/parasitologia , Infecções por Spirurida/veterinária , Espirurídios/classificação , Animais , Costa Rica/epidemiologia , DNA Ribossômico/genética , Feminino , Nematoides/classificação , Nicarágua/epidemiologia , Filogenia , Especificidade da Espécie , Espirurídios/genética , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Estados Unidos
8.
Parasitol Res ; 120(6): 2037-2046, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33893550

RESUMO

The first data on a whole mitochondrial genome of Haploporidae, Parasaccocoelium mugili (Digenea: Haploporata: Haploporidae) was generated using the next-generation sequencing (NGS) approach. We sequenced the complete mitochondrial DNA (mtDNA) and ribosomal operon of Parasaccocoelium mugili, intestine parasite of mullet fish. The mtDNA of P. mugili contained 14,021 bp, including 12 protein-coding genes, two ribosomal genes, 22 tRNA genes, and non-coding region. The ribosomal operon of P. mugili was 8308 bp in length, including 18S rRNA gene (1981 bp), ITS1 rDNA (955 bp), 5.8S rRNA gene (157 bp), ITS2 rDNA (268 bp), 28S rRNA gene (4180 bp), and ETS (767 bp). We used the mtDNA protein-coding regions to make phylogenetic reconstructions of Haploporidae. Additionally, we performed the sequence cluster analysis based on codon usage bias of most of currently available mitochondrial genome data for trematodes. The observed gene arrangement in mtDNA sequence of P. mugili is identical to those of Plagiorchis maculosus (Rudolphi, 1802). Results of maximum likelihood (ML) phylogenetic analysis showed that P. mugili was closely related to Paragonimus species from the suborder Xiphidiata. The results of sequence cluster analysis based on codon usage bias showed that P. mugili has the highest similarity with Plagiorchis maculosus (Xiphidiata). Our results do not contradict to proposing a new suborder for Haploporoidea-Haploporata. On the basis of obtained results, the relationship between mitochondrial protein-coding gene rearrangements and synonymous nucleotide substitutions in mitochondrial genomes has been suggested.


Assuntos
Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Trematódeos/genética , Animais , DNA Mitocondrial/genética , DNA Ribossômico/genética , Doenças dos Peixes/parasitologia , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Smegmamorpha/parasitologia , Trematódeos/classificação , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , Óperon de RNAr/genética
9.
Cytogenet Genome Res ; 161(1-2): 52-62, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33887732

RESUMO

With 82 species currently described, the genus Leptodactylus is the most diverse and representative one in the family Leptodactylidae. Concerning chromosomal organization, this genus represents an interesting and underexplored group since data from molecular cytogenetics are incipient, and little is known about the organization and distribution of repetitive DNA elements in the karyotypes. In this sense, this study aimed at providing a comparative analysis in 4 Leptodactylus species (L. macrosternum, L. pentadactylus, L. fuscus, and Leptodactylus cf. podicipinus), combining conventional cytogenetics (Giemsa staining, C-banding, and AgNOR staining) and mapping of molecular markers (18S rDNA, telomeric and microsatellite probes), to investigate mechanisms underlying their karyotype differentiation process. The results showed that all species had karyotypes with 2n = 22 and FN = 44, except for Leptodactylus cf. podicipinus which presented FN = 36. The 18S rDNA was observed in pair 8 of all analyzed species (corresponding to pair 4 in L. pentadactylus), coinciding with the secondary constrictions and AgNOR staining. FISH with microsatellite DNA probes demonstrated species-specific patterns, as well as an association of these repetitive sequences with constitutive heterochromatin blocks and ribosomal DNA clusters, revealing the dynamics of microsatellites in the genome of the analyzed species. In summary, our data demonstrate an ongoing process of genomic divergence inside species with almost similar karyotype, driven most likely by a series of pericentric inversions, followed by differential accumulation of repetitive sequences.


Assuntos
Anuros/genética , Cromossomos/ultraestrutura , DNA Ribossômico/genética , Cariotipagem , Repetições de Microssatélites , Animais , Bandeamento Cromossômico , Inversão Cromossômica , Análise Citogenética , Citogenética , Sondas de DNA , Feminino , Geografia , Heterocromatina/metabolismo , Hibridização in Situ Fluorescente , Cariótipo , Masculino , Meiose , Mitose , Região Organizadora do Nucléolo , Filogenia , Especificidade da Espécie
10.
Zootaxa ; 4950(1): zootaxa.4950.1.2, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33903318

RESUMO

We provide data on the cytochrome c oxidase subunit I (COI) and 16S rDNA genes for eight species of common hard ticks in Xinjiang: Dermacentor montanus, D. niveus, Haemaphysalis sulcate, Hyalomma asiaticum asiaticum, Hya. detritum, Hya. scupense, Rhipicephalus sanguineus and R. pumilio. Genetic distances, calculated based on the Kimura two-parameter (K2P) distance model, found the same trend of intraspecies level≤interspecies levelintragenus level. Phylogenetic trees, constructed with the neighbor-joining (NJ) and minimum-evolution (ME) methods, demonstrated that each species clustered into separate clades, thus confirming the usefulness of CO1 and 16S rDNA genes for tick species identification. The genera Dermacentor, Haemaphysalis and Rhipicephalus were all recovered in the phylogenetic analysis, as was the subfamily Rhipicephalinae, but a monophyletic Hyalomma was not.


Assuntos
Ixodidae , Animais , China , DNA Ribossômico/genética , Ixodidae/classificação , Ixodidae/genética , Ixodidae/fisiologia , Filogenia , Rhipicephalus
11.
Parasitol Res ; 120(6): 2047-2056, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33893552

RESUMO

Nematodes of the genus Physaloptera are globally distributed and infect a multitude of hosts. Their life cycle involves orthopterans and coleopterans as intermediate hosts. The morphological characters alone are inadequate to detect and differentiate Physaloptera spp. from its congeners. Moreover, molecular studies are limited to compare them precisely. The present communication reports the first molecular phylogenetic characterization of feline Physaloptera spp. from India based on mitochondrial cytochrome c oxidase subunit 1 (COX1) and small subunit ribosomal DNA (18S rDNA). The nematodes were first isolated from the stomach of adult stray cats during necropsy examination. Based on the gross and microscopic characters, the worms were identified as P. praeputialis. Morphological identification was further confirmed through PCR targeting the barcode region of the mitochondrial cytochrome c oxidase subunit I (MT-COI) gene, using nematode-specific primers cocktail followed by species specific primers targeting partial COX1 and 18S rRNA genes. Generated sequences were submitted in NCBI GenBank (MW517846, MW410927, MW411349), and phylogenetic trees were constructed using the maximum likelihood method. When compared with other sequences of Physaloptera species across the globe, the present isolates showed 85.6-97.7% and 97.3-99% nucleotide homology based on COX1 and 18S rRNA gene, respectively. BLASTn analysis revealed a strong identity to other Physaloptera spp., and the phylogenetic tree placed all Physaloptera spp. in the same cluster. This study again indicates the usefulness of molecular techniques to substantiate the identity of species that may lack adequate descriptions and impart new insight for the potentially overlooked significance of P. praeputialis infections in felines.


Assuntos
Gatos/parasitologia , Filogenia , Spiruroidea/classificação , Animais , DNA de Helmintos/genética , DNA Ribossômico/genética , Genes Mitocondriais/genética , Índia , Análise de Sequência de DNA , Especificidade da Espécie , Spiruroidea/genética , Spiruroidea/isolamento & purificação
12.
BMC Infect Dis ; 21(1): 373, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882835

RESUMO

BACKGROUND: Aberrant microbiota composition has been linked to disease development at numerous anatomical sites. Microbiota changes in reaction to viral infections, such as human papillomavirus (HPV), have been investigated almost exclusively in the female reproductive tract. However, HPV infection may also affect male health by reducing semen quality and fertility. The aim of this study was to investigate whether present HPV DNA is associated with detectable changes in semen bacterial microbiota composition and diversity. METHODS: This study relied on stored semen samples from 31 fertile healthy men who participated in the Finnish family HPV Study during the years 1998-2001. DNA was extracted from semen with PCR template preparation kit. HPV was genotyped using Luminex-based Multimetrix® assay. Microbiota was analyzed from the V3-V4 region of 16S rDNA gene following sequencing on an Illumina MiSeq platform. All statistical analyses were performed with Calypso software version 8.84. RESULTS: HPV DNA was detected in 19.4% (6/31) of the semen samples. HPV status in the semen did not impact the α-diversity estimations, as measured by Chao1 and Shannon indices, nor ß-diversity. Nevertheless, HPV-positive semen samples exhibited differences in the taxonomic composition of the bacterial microbiota including higher abundances of Moraxellaceae (p = 0.028), Streptococcus (p = 0.0058) and Peptostreptococcus (p = 0.012) compared to HPV-negative semen samples. CONCLUSION: HPV infection is associated with altered bacterial microbiota composition in semen, and this might have in impact to male health in general. As of present, it is unclear whether these changes result from HPV infection or whether altered bacterial microbiota increases susceptibility to HPV infection. More research is needed on viral-bacterial interactions in the male reproductive system.


Assuntos
Bactérias/genética , Microbiota/genética , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Sêmen/microbiologia , Adulto , DNA Ribossômico/genética , DNA Viral/genética , Feminino , Finlândia/epidemiologia , Genótipo , Voluntários Saudáveis , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Análise do Sêmen , Adulto Jovem
13.
J Phycol ; 57(3): 1059-1083, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33650126

RESUMO

Identification of species of the dinoflagellate genus Ostreopsis is difficult because several species have been poorly described, others misidentified in the literature, and the type species, O. siamensis, has not been described by contemporary taxonomic methods. In the present study, it is argued that Ostreopsis sp. 6 as described by previous authors is similar to the type species, and we offer an emended description of O. siamensis by LM, SEM, and molecular analyses of nuclear LSU and ITS rDNA based on material collected a few hundred kilometers from the type locality in the Gulf of Thailand and along the Vietnamese east coast. Ostreopsis siamensis is genetically different from the species reported as O. cf. siamensis in the literature and the latter should be described as a separate species. It is also concluded that with the poor knowledge of the morphological variability of many species of Ostreopsis, O. siamensis may not be distinguished from other similar-sized species by its morphological features, and hence molecular data are needed for reliable identification. The species Ostreopsis lenticularis and Ostreopsis cf. ovata were also found and described.


Assuntos
Dinoflagelados , Grupo com Ancestrais do Continente Asiático , DNA Ribossômico/genética , Dinoflagelados/genética , Humanos
14.
Biomolecules ; 11(2)2021 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672873

RESUMO

Polysaccharides from marine algae are one novel source of plant defense elicitors for alternative and eco-friendly plant protection against phytopathogens. The effect of exopolysaccharides (EPS) produced by Porphyridium sordidum on elicitation of Arabidopsis thaliana defense responses against Fusarium oxysporum was evaluated. Firstly, in order to enhance EPS production, a Box-Behnken experimental design was carried out to optimize NaCl, NaNO3 and MgSO4 concentrations in the culture medium of microalgae. A maximum EPS production (2.45 g/L) higher than that of the control (0.7 g/L) was observed for 41.62 g/L NaCl, 0.63 g/L NaNO3 and 7.2 g/L MgSO4 concentrations. Structurally, the EPS contained mainly galactose, xylose and glucose. Secondly, the elicitor effect of EPS was evaluated by investigating the plant defense-related signaling pathways that include activation of Salicylic or Jasmonic Acid-dependent pathway genes. A solution of 2 mg/mL of EPS has led to the control of fungal growth by the plant. Results showed that EPS foliar application induced phenylalaline ammonia lyase and H2O2 accumulation. Expression profile analysis of the defense-related genes using qRT-PCR revealed the up-regulation of Superoxide dismutases (SOD), Peroxidase (POD), Pathogenesis-related protein 1 (PR-1) and Cytochrome P450 monooxyge-nase (CYP), while Catalase (CAT) and Plant defensin 1.2 (PDF1.2) were not induced. Results suggest that EPS may induce the elicitation of A. thaliana's defense response against F. oxysporum, activating the Salicylic Acid pathway.


Assuntos
Arabidopsis/efeitos dos fármacos , Fusarium/imunologia , Polissacarídeos/biossíntese , Porphyridium/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , DNA Ribossômico/genética , Interações Hospedeiro-Patógeno , Peróxido de Hidrogênio/metabolismo , Polissacarídeos/farmacologia , Porphyridium/classificação , Porphyridium/genética , RNA Ribossômico 18S/genética
15.
Environ Int ; 153: 106525, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33774497

RESUMO

Hexavalent Chromium [Cr (VI)] is an established toxicant, carcinogen, and a significant source of public health concern. The multicopy ribosomal DNA (rDNA) array is mechanistically linked to aging and cancer, is the most evolutionarily conserved segment of the human genome, and gives origin to nucleolus, a nuclear organelle where ribosomes are assembled. Here we show that exposure to Cr (VI) induces instability in the rDNA, triggering cycles of rapid, specific, and transient amplification and contraction of the array in human cells. The dynamic of environmentally responsive rDNA copy number (CN) amplification and contraction occurs at doses to which millions of individuals are regularly exposed. Finally, analyses of human populations occupationally exposed to Cr (VI) indicate that environmental exposure history and drinking habits but not age shape extensive naturally occurring rDNA copy number variation. Our observations identify a novel pathway of response to hexavalent chromium exposure and raise the prospect that a suite of environmental determinants of rDNA copy number remain to be discovered.


Assuntos
Cromo , Variações do Número de Cópias de DNA , Carcinógenos , Cromo/toxicidade , DNA Ribossômico/genética , Humanos
16.
Parasitol Res ; 120(5): 1845-1850, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33666756

RESUMO

A reintroduced white-tailed sea eagle (Haliaeetus albicilla) in moderate body condition was found dead and submitted for post-mortem examination. There were no signs of disease on gross pathological examination. Histopathological examination however revealed the presence of encysted protozoan parasites in pectoral and cardiac muscle sections. Polymerase chain reaction amplification of extracted genomic DNA and sequencing of four regions: the 18S rDNA, 28S rDNA, internal transcribed spacer (ITS) 1, and RNA polymerase B (rpoB) loci, confirmed the presence of a Sarcocystis species in pectoral and cardiac muscle which appeared phylogenetically similar to Sarcocystis wobeseri. This is the first report of S. wobeseri-like infection in a white-tailed sea eagle revealing a new intermediate host species for this parasite.


Assuntos
Doenças das Aves/parasitologia , Águias/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , DNA Ribossômico/genética , Masculino , Filogenia , Reação em Cadeia da Polimerase , Sarcocystis/genética , Sarcocystis/fisiologia , Sarcocistose/parasitologia
17.
Methods Mol Biol ; 2283: 83-92, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33765312

RESUMO

In this chapter, we provide a methodological description of the process to perform gastrointestinal (GIT) microbiota profiling on human stool samples. The process includes: (i) collection of feces, (ii) isolation of DNA from fecal community bacteria, (iii) selection of both 16S rDNA sequencing target and next-generation sequencing platform, and (iv) analysis and interpretation of sequence data. The process culminates into a comprehensive report on the GIT microbiota composition and structure that may translate into clinically actionable results.


Assuntos
Bactérias/classificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Fezes/microbiologia , Microbioma Gastrointestinal , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia
18.
Parasitol Res ; 120(6): 2017-2030, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33772348

RESUMO

The genetic diversity of Syphacia nematodes (intestinal parasites of rodents) was studied in the hybrid zone of two sister species of common voles, Microtus arvalis and Microtus obscurus, in the Oka River valley, east of Moscow. Syphacia nematodes of other rodent species (Microtus rossiaemeridionalis, Alexandromys oeconomus, Sylvaemus uralensis, and Apodemus agrarius) that inhabit the area were also studied. Phylogenetic trees for the studied nematodes were inferred from the analysis of nuclear ITS1+5.8S+ITS2, LSU rDNA, and mitochondrial CO1 gene partial sequences. Syphacia nematodes of the studied area form three well-defined clades in the phylogenetic tree of this genus. Morphological analysis revealed similarities between the obtained sequences with those of known Syphacia species from the GenBank database, which enabled identifying these three clades up to the species level: S. montana, S. agraria, and S. frederici. Russian haplotypes of Syphacia are different from West European and East Asian haplotypes with pronounced genetic distances. A high level of specificity was reported for two of these three species (S. frederici, only in Sylvaemus uralensis; S. agraria, only in Apodemus agrarius). S. montana was found in different species of voles. Remarkably, S. montana specimens from M. arvalis and M. obscurus were genetically uniform, while S. montana, specimens from hybrids between these two species formed a separate clade distant from those originating from non-hybridised hosts.


Assuntos
Variação Genética , Oxyuroidea/genética , Doenças dos Roedores/parasitologia , Roedores/genética , Animais , DNA Ribossômico/genética , Hibridização Genética , Oxyuroidea/classificação , Filogenia , Federação Russa , Especificidade da Espécie
19.
Mol Genet Genomics ; 296(3): 677-688, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33738520

RESUMO

Contaminations in sequencing data, especially in reference genomes, lead to inevitable errors in downstream analyses. Similarly, presence of contaminants in transcriptomes, misrepresents the molecular basis of various interactions. In this study, we report the presence of a large number of plant transcriptomes contaminated with RNAs encoding POU domain proteins; a family of proteins that has not been reported in plants and fungi. Besides, our findings illustrated that there are four POU domain protein-coding sequences in the reference genome of Rhodamnia argentea. It turned out that the existing foreign fragments are related to arthropods that are considered as plant pests. We also identified two contaminated draft genomes, Humulus lupulus and Cannabis sativa that contained complete rDNA sequences originating from Tetranychus species. As a result, careful screening of sequencing data before releasing them in public databases or checking existing genomes for possible contaminations is recommended.


Assuntos
Genoma de Planta/genética , Fator 3 de Transcrição de Octâmero/genética , Fatores do Domínio POU/genética , Plantas/genética , Transcriptoma/genética , Animais , Cannabis/genética , DNA Ribossômico/genética , Fungos/genética , Humanos , Humulus/genética , Ácaros/genética , Myrtaceae/genética
20.
Curr Microbiol ; 78(4): 1432-1447, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33651191

RESUMO

Salvia multicaulis has been an important medicinal plant in Iran and several East Asian countries for hundreds of years. Because of growing demand, overharvesting of wild S. multicaulis has endangered its wild populations. Endophytes are well known for protecting wild plant populations against biotic and abiotic stresses, especially under harsh situations, as well as for their plant growth enhancement activities. Since no information was on endophyte biology in S. multicaulis, here we aimed at analyzing diversity and spatiotemporal distribution of fungal endophytes associating S. multicaulis in their main wild habitats in Iran, i.e., Qazvin, Alborz and Mazandaran provinces. A total of 153 fungal endophytes were isolated and identified according to their morphology and ribosomal ITS rDNA sequences. As results indicated Ascomycota dominated in colonizing S. multicaulis with a relative frequency (RF) of 96.77%, comprising of Eurotiomycetes (RF: 40.5%), Sordariomycetes (RF: 33.9%) and Dothideomycetes (RF: 20.5%). Mucoromycota, comprised the rest of endophytes (RF: 5.23%). The entire fungal microbiome was classified into nine genera including Fusarium (25.5%), Penicillium (21.5%), Aspergillus (17.0%), Alternaria (15.5%), Colletotrichum (5.2%), Rhizopus (5.2%), Macrophomina (4.5%), Trichoderma (3.25%) and Nodulisporium (2.0%). Analyses of different diversity indices indicated significant correlations with tissue type, sampling locations and season of recovery. Almost 43% of fungal endophytes were recovered at Mazandaran, Kojur; 35.4% at Qazvin, Barajin Forest Park; 30.1% at Alborz, Taleqan; and 21% at Alborz, Mahdasht. The highest overall endophyte recovery was in summer (36.8%), followed by spring (31.6%), autumn (21%), and winter (10.5%). In total, the number of endophytes recovered from roots (91) was higher than those of stems (32) and leaves (30), especially during autumn and winter. Accordingly, we conclude that Ascomycota are the major endophytic fungi colonizing S. multicaulis, and that sampling location, tissue type and season can affect the fungal endophyte composition of this medicinal plant. This knowledge could be further applied in protection and health management of this endangered species.


Assuntos
Ascomicetos , Salvia , Ascomicetos/genética , Biodiversidade , DNA Ribossômico/genética , Endófitos/genética , Fungos/genética , Irã (Geográfico) , Filogenia , Folhas de Planta
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