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1.
Int J Mol Sci ; 22(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672964

RESUMO

Mitochondrial genomes (mitogenomes) are an excellent source of information for phylogenetic and evolutionary studies, but their application in marine invertebrates is limited. In the present study, we utilized mitogenomes to elucidate the phylogeny and environmental adaptation in deep-sea mussels (Mytilidae: Bathymodiolinae). We sequenced and assembled seven bathymodioline mitogenomes. A phylogenetic analysis integrating the seven newly assembled and six previously reported bathymodioline mitogenomes revealed that these bathymodiolines are divided into three well-supported clades represented by five Gigantidas species, six Bathymodiolus species, and two "Bathymodiolus" species, respectively. A Common interval Rearrangement Explorer (CREx) analysis revealed a gene order rearrangement in bathymodiolines that is distinct from that in other shallow-water mytilids. The CREx analysis also suggested that reversal, transposition, and tandem duplications with subsequent random gene loss (TDRL) may have been responsible for the evolution of mitochondrial gene orders in bathymodiolines. Moreover, a comparison of the mitogenomes of shallow-water and deep-sea mussels revealed that the latter lineage has experienced relaxed purifying selection, but 16 residues of the atp6, nad4, nad2, cob, nad5, and cox2 genes have underwent positive selection. Overall, this study provides new insights into the phylogenetic relationships and mitogenomic adaptations of deep-sea mussels.


Assuntos
Adaptação Fisiológica/genética , Bivalves/genética , Genoma Mitocondrial/genética , Filogenia , Animais , Bivalves/classificação , DNA Mitocondrial/genética , Ordem dos Genes , Rearranjo Gênico , Genes Mitocondriais/genética , Variação Genética , Taxa de Mutação , Água do Mar , Análise de Sequência de DNA/métodos , Especificidade da Espécie
2.
Parasitol Res ; 120(5): 1677-1686, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33754190

RESUMO

Different species of the genus Ophidascaris (Baylis, 1921; Nematoda: Ascaridida, Ascaridoidea) are intestinal parasites of various snake species. More than 30 Ophidascaris species have been reported worldwide; however, few molecular genetic studies have been conducted on this genus. We sequenced the complete mitogenome of Ophidascaris wangi parasitizing two snake species of the family Colubridae, i.e., Elaphe carinata (Günther, 1864) and Dinodon rufozonatum. The mitogenome sequence of O. wangi was approximately 14,660 base pairs (bp) long and encoded 36 genes, including 12 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, and 22 transfer RNA genes. Gene arrangement, genome content, and transcription direction were in line with those in Toxascaris leonina (Linstow, 1902; Ascaridida: Ascarididae). Phylogenetics of O. wangi and other ascaridoids were reconstructed based on the concatenated amino acid sequences of 12 PCGs, and on nucleotide sequences of 12 PCGs and two rRNA genes. Phylogenetic analyses were performed using maximum likelihood and Bayesian inference methods, and the results suggested that O. wangi constitutes a sister clade of Ascaris, Parascaris, Baylisascaris, and Toxascaris within the family Ascarididae, which is a sister clade of Toxocaridae. The mitogenome sequence of O. wangi obtained from the present study will be useful for future identification of the nematode worms in the genus Ophidascaris and will increase the understanding of population genetics, molecular epidemiology, and phylogenetics of ascaridoid nematodes in snakes.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/genética , Colubridae/parasitologia , Genoma Mitocondrial/genética , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/classificação , Ascaridoidea/isolamento & purificação , China , Colubridae/classificação , DNA Mitocondrial/genética , Ordem dos Genes , Genes Mitocondriais/genética , Filogenia
3.
Nat Commun ; 12(1): 1190, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608520

RESUMO

DddA-derived cytosine base editors (DdCBEs), composed of the split interbacterial toxin DddAtox, transcription activator-like effector (TALE), and uracil glycosylase inhibitor (UGI), enable targeted C-to-T base conversions in mitochondrial DNA (mtDNA). Here, we demonstrate highly efficient mtDNA editing in mouse embryos using custom-designed DdCBEs. We target the mitochondrial gene, MT-ND5 (ND5), which encodes a subunit of NADH dehydrogenase that catalyzes NADH dehydration and electron transfer to ubiquinone, to obtain several mtDNA mutations, including m.G12918A associated with human mitochondrial diseases and m.C12336T that incorporates a premature stop codon, creating mitochondrial disease models in mice and demonstrating a potential for the treatment of mitochondrial disorders.


Assuntos
DNA Mitocondrial/genética , Edição de Genes/métodos , Genes Mitocondriais/genética , Animais , Transporte de Elétrons , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Mutação , NADH Desidrogenase/genética , Células NIH 3T3 , Efetores Semelhantes a Ativadores de Transcrição/genética
4.
Gene ; 777: 145467, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33524519

RESUMO

The current research on Ephemeroptera is mainly based on its morphology, since only small numbers of mitogenomes have been reported. In this study, the mitogenomes of Epeorus carinatus (15,338 bp) and E. dayongensis (15,609 bp) were sequenced, annotated and compared to genome data from congeners. Both mitogenomes had 23 tRNA genes including standard 22 and one extra tRNAMet. The duplicated tRNAMet gene had been found in other heptageniid species except Paegniodes cupulatus, suggesting it could be used as a molecular synapomorphy for partial Heptageniidae. The phylogenetic analyses based on Bayesian Inference (BI) and Maximum Likelihood (ML) showed that Heptageniidae was monophyletic and the relationships among known Epeorus species were ((E. carinatus + E. herklotsi) + (E. dayongensis + E. sp. 1)), which implied the focal species E. carinatus and E. dayongensis should be grouped into different subgenera.


Assuntos
Ephemeroptera/genética , Genes Mitocondriais/genética , Genoma Mitocondrial/genética , Animais , Composição de Bases/genética , Sequência de Bases/genética , Ephemeroptera/classificação , Genômica/métodos , Filogenia , RNA de Transferência/genética
5.
Mol Biol Rep ; 48(2): 1281-1290, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33582950

RESUMO

The estuarine firefly, Pteroptyx tener, aggregates in the thousands in mangrove trees lining tidal rivers in Southeast Asia where they engage one another in a nocturnal, pre-mating ritual of synchronised courtship flashes. Unfortunately, populations of the species by virtue of being restricted to isolated estuarine rivers systems in the region, are at risk of genetic isolation. Because of this concern we undertook the task of sequencing and characterising the mitochondrial DNA genome of P. tener, as the first step towards helping us to characterise and better understand their genetic diversity. We sequenced and assembled the mitochondrial DNA genome of P. tener from two male and female specimens from the district of Kuala Selangor in Peninsular Malaysia and announce the molecules in this publication. We also reconstructed the phylogenetic trees of all available lampyrids mitogenomes and suggest the need to re-examine our current understanding of their classification which have largely been based on morphological data and the cox1 gene. Separately, our analysis of codon usage patterns among lampyrid mitogenomes showed that the codon usage in a majority of the protein-coding genes were non-neutral. Codon usage patterns between mitogenome sequences of P. tener were, however, largely neutral. Our findings demonstrate the usefulness of mitochondrial genes/mitogenomes for analysing both inter- and intra- specific variation in the Lampyridae to aid in species discovery in this highly variable genus; and elucidate the phylogenetic relationships of Pteroptyx spp. from the region.


Assuntos
DNA Mitocondrial/genética , Vaga-Lumes/genética , Genoma Mitocondrial/genética , Animais , Besouros/genética , Genes Mitocondriais/genética , Anotação de Sequência Molecular , Filogenia , Sequenciamento Completo do Genoma
6.
Gene ; 777: 145462, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33515725

RESUMO

A universal phenomenon of using synonymous codons unequally in coding sequences known as codon usage bias (CUB) is observed in all forms of life. Mutation and natural selection drive CUB in many species but the relative role of evolutionary forces varies across species, genes and genomes. We studied the CUB in mitochondrial (mt) CO genes from three orders of Amphibia using bioinformatics approach as no work was reported yet. We observed that CUB of mt CO genes of Amphibians was weak across different orders. Order Caudata had higher CUB followed by Gymnophiona and Anura for all genes and CUB also varied across genes. Nucleotide composition analysis showed that CO genes were AT-rich. The AT content in Caudata was higher than that in Gymnophiona while Anura showed the least content. Multiple investigations namely nucleotide composition, correspondence analysis, parity plot analysis showed that the interplay of mutation pressure and natural selection caused CUB in these genes. Neutrality plot suggested the involvement of natural selection was more than the mutation pressure. The contribution of natural selection was higher in Anura than Gymnophiona and the lowest in Caudata. The codons CGA, TGA, AAA were found to be highly favoured by nature across all genes and orders.


Assuntos
Anfíbios/genética , Uso do Códon/genética , Genes Mitocondriais/genética , Anfíbios/metabolismo , Animais , Evolução Biológica , Códon/genética , Biologia Computacional , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Evolução Molecular , Mutação/genética , Seleção Genética/genética
7.
Int J Biol Macromol ; 170: 717-727, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33412200

RESUMO

Brachyura is one of the most species rich and highly derived groups among extant crustaceans, with over 7250 known species. However, brachyuran phylogeny remains controversial and requires further study. Here, we combined 103 brachyuran mitogenomes from GenBank with 10 new mitogenomes to describe gene rearrangement patterns and explore the internal phylogenetic relationships of Brachyura. Most of the 10 novel mitogenomes had the typical 37 genes, except that of Longpotamon depressum, which lacked trnQ. We discovered 15 gene rearrangement patterns among Brachyura and preliminarily determined their rearrangement mechanisms with the help of CREx. We identified seven putative ancestral family gene orders among the 15 rearrangement patterns and expounded systematically upon the mechanisms of their rearrangement. In our phylogenetic analysis, Raninoida shared a sister relationship with an eubrachyuran clade ((Heterotremata [Potamoidea] + Thoracotremata) + Heterotremata) at maximum nodal support rather than Dromiacea, which did not support monophyly of Podotremata. In addition, Potamoidea (Parathelphusidae + Potamidae) retained a close relationship with Thoracotremata rather than their marine relatives in Heterotremata. Our study provides important information for the evolution of Brachyura by using the large taxon sampling currently available for systematic rearrangement and phylogenetic analyses.


Assuntos
Braquiúros/genética , Ordem dos Genes/genética , Rearranjo Gênico/genética , Genes Mitocondriais/genética , Mitocôndrias/genética , Animais , Genoma Mitocondrial/genética , Filogenia
8.
Invest Ophthalmol Vis Sci ; 61(12): 13, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049061

RESUMO

Purpose: The coronavirus disease 2019 (COVID-19) pandemic severely challenges public health and necessitates the need for increasing our understanding of COVID-19 pathogenesis, especially host factors facilitating virus infection and propagation. The aim of this study was to investigate key factors for cellular susceptibility to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection in the ocular surface cells. Methods: We combined co-expression and SARS-CoV-2 interactome network to predict key genes at COVID-19 in ocular infection based on the premise that genes underlying a disease are often functionally related and functionally related genes are often co-expressed. Results: The co-expression network was constructed by mapping the well-known angiotensin converting enzyme (ACE2), TMPRSS2, and host susceptibility genes implicated in COVID-19 genomewide association study (GWAS) onto a cornea, retinal pigment epithelium, and lung. We found a significant co-expression module of these genes in the cornea, revealing that cornea is potential extra-respiratory entry portal of SARS-CoV-2. Strikingly, both co-expression and interaction networks show a significant enrichment in mitochondrial function, which are the hub of cellular oxidative homeostasis, inflammation, and innate immune response. We identified a corneal mitochondrial susceptibility module (CMSM) of 14 mitochondrial genes by integrating ACE2 co-expression cluster and SARS-CoV-2 interactome. The gene ECSIT, as a cytosolic adaptor protein involved in inflammatory responses, exhibits the strongest correlation with ACE2 in CMSM, which has shown to be an important risk factor for SARS-CoV-2 infection and prognosis. Conclusions: Our co-expression and protein interaction network analysis uncover that the mitochondrial function related genes in cornea contribute to the dissection of COVID-19 susceptibility and potential therapeutic interventions.


Assuntos
Betacoronavirus , Córnea/metabolismo , Infecções por Coronavirus/genética , Regulação da Expressão Gênica , Genes Mitocondriais/genética , Peptidil Dipeptidase A/genética , Pneumonia Viral/genética , RNA/genética , Linhagem Celular , Córnea/patologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/metabolismo , Humanos , Pandemias , Peptidil Dipeptidase A/biossíntese , Pneumonia Viral/epidemiologia , Pneumonia Viral/metabolismo
9.
Parasitol Res ; 119(10): 3359-3368, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32893331

RESUMO

Acanthocephalans are multi-host endoparasites, many of which use freshwater amphipods as intermediate hosts for their larval stages (e.g., cystacanths) while adults live in the intestines of vertebrates, including waterfowl. In central Alberta, Canada, several co-occurring species of the acanthocephalan genus Polymorphus use the amphipod Gammarus lacustris Sars, 1863 as an intermediate host. We applied DNA barcoding and morphometric analysis to differentiate cystacanth larvae from G. lacustris sampled from 17 Albertan water bodies. We slide-mounted specimens and measured morphological traits relating to proboscis hooks. We sequenced the standard DNA barcoding region of the mitochondrial cytochrome c oxidase subunit I gene (COI). Morphometric analysis suggested that the acanthocephalans we collected belonged to four morphologically different groups that keyed to Polymorphus contortus (Bremser, 1821) Travassos, 1926; P. marilis Van Cleave, 1939; P. paradoxus Connel et Corner, 1957; and P. strumosoides (Lundström, 1942) Amin, 2013. Our Bayesian tree based on COI sequences generally corroborated the morphological results and supported that the specimens assigned to P. cf. contortus and P. cf. strumosoides belong to two distinct species. In contrast, the Bayesian tree showed that specimens of P. cf. marilis were nested as a cluster within the P. cf. paradoxus clade. Similarly, small pairwise genetic distance (< 2%) between specimens identified as P. cf. contortus and P. cf. strumosoides suggests that they are conspecific. Future studies should use morphology and sequence data from adult acanthocephalans to assess the taxonomic identity of the cystacanth-based Polymorphus taxa. Our study is the first to provide genetic information for the four Polymorphus taxa and emphasizes the importance of applying multiple approaches to differentiate parasite species.


Assuntos
Acantocéfalos/classificação , Acantocéfalos/anatomia & histologia , Acantocéfalos/genética , Alberta , Anfípodes/parasitologia , Animais , Código de Barras de DNA Taxonômico , Água Doce/parasitologia , Genes de Helmintos/genética , Genes Mitocondriais/genética , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Especificidade da Espécie
10.
Parasitol Res ; 119(10): 3531-3534, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32827103

RESUMO

In this study, we describe a rare human case with corneal ulcer caused by thelaziosis in a 69-year-old man in Southwest China. A male nematode was discovered and removed from the patient's right eye with a long spicule and further identified by sequencing mitochondrial cox1 gene. The ophthalmologic and molecular biological evidence demonstrates the corneal ulcer caused by T. callipaeda infection, which is mainly distributed in Asian and European countries. Most T. callipaeda infections are emerged in the conjunctiva, leading to conjunctivitis. To the best knowledge of the authors, corneal ulcers caused by T. callipaeda have not been reported yet.


Assuntos
Úlcera da Córnea/parasitologia , Infecções por Spirurida/parasitologia , Thelazioidea/isolamento & purificação , Idoso , Animais , China , Túnica Conjuntiva/parasitologia , Genes de Helmintos/genética , Genes Mitocondriais/genética , Humanos , Masculino , Thelazioidea/citologia , Thelazioidea/genética
11.
PLoS One ; 15(7): e0235430, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32722672

RESUMO

Phylogeographic relationships among global collections of the mosquito Aedes aegypti were evaluated using the mitochondrial Cytochrome C Oxidase 1 (CO1) and NADH dehydrogenase subunit 4 (ND4) genes including new sequences from Sri Lanka. Phylogeographic analysis estimated that Ae. aegypti arose as a species ~614 thousand years ago (kya) in the late Pleistocene. At 545 kya an "early" East African clade arose that continued to differentiate in East Africa, and eventually gave rise to three lineages one of which is distributed throughout all tropical and subtropical regions, a second that contains Southeast Asian/Sri Lankan mosquitoes and a third that contains mostly New World mosquitoes. West African collections were not represented in this early clade. The late clade continued to differentiate throughout Africa and gave rise to a lineage that spread globally. The most recent branches of the late clade are represented by South-East Asia and India/Pakistan collections. Analysis of migration rates suggests abundant gene flow between India/Pakistan and the rest of the world with the exception of Africa.


Assuntos
Aedes/genética , DNA Mitocondrial/genética , Mitocôndrias/genética , Filogeografia , Aedes/classificação , África , África Oriental , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fluxo Gênico , Genes Mitocondriais/genética , Haplótipos , Índia , Mitocôndrias/metabolismo , Paquistão , Filogenia , Sri Lanka
12.
Nature ; 583(7817): 631-637, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641830

RESUMO

Bacterial toxins represent a vast reservoir of biochemical diversity that can be repurposed for biomedical applications. Such proteins include a group of predicted interbacterial toxins of the deaminase superfamily, members of which have found application in gene-editing techniques1,2. Because previously described cytidine deaminases operate on single-stranded nucleic acids3, their use in base editing requires the unwinding of double-stranded DNA (dsDNA)-for example by a CRISPR-Cas9 system. Base editing within mitochondrial DNA (mtDNA), however, has thus far been hindered by challenges associated with the delivery of guide RNA into the mitochondria4. As a consequence, manipulation of mtDNA to date has been limited to the targeted destruction of the mitochondrial genome by designer nucleases9,10.Here we describe an interbacterial toxin, which we name DddA, that catalyses the deamination of cytidines within dsDNA. We engineered split-DddA halves that are non-toxic and inactive until brought together on target DNA by adjacently bound programmable DNA-binding proteins. Fusions of the split-DddA halves, transcription activator-like effector array proteins, and a uracil glycosylase inhibitor resulted in RNA-free DddA-derived cytosine base editors (DdCBEs) that catalyse C•G-to-T•A conversions in human mtDNA with high target specificity and product purity. We used DdCBEs to model a disease-associated mtDNA mutation in human cells, resulting in changes in respiration rates and oxidative phosphorylation. CRISPR-free DdCBEs enable the precise manipulation of mtDNA, rather than the elimination of mtDNA copies that results from its cleavage by targeted nucleases, with broad implications for the study and potential treatment of mitochondrial disorders.


Assuntos
Toxinas Bacterianas/metabolismo , Citidina Desaminase/metabolismo , DNA Mitocondrial/genética , Edição de Genes/métodos , Genes Mitocondriais/genética , Mitocôndrias/genética , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Sequência de Bases , Burkholderia cenocepacia/enzimologia , Burkholderia cenocepacia/genética , Respiração Celular/genética , Citidina/metabolismo , Citidina Desaminase/química , Citidina Desaminase/genética , Genoma Mitocondrial/genética , Células HEK293 , Humanos , Doenças Mitocondriais/genética , Doenças Mitocondriais/terapia , Mutação , Fosforilação Oxidativa , Engenharia de Proteínas , RNA Guia/genética , Especificidade por Substrato , Sistemas de Secreção Tipo VI/metabolismo
13.
Parasitol Res ; 119(7): 2347-2350, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32488623

RESUMO

Thelazia callipaeda (Spirurida, Thelaziidae) is a vector-borne zoonotic eyeworm able to infect a broad spectrum of carnivores. Here, we describe the first case of bilateral infection by T. callipaeda in the eyes of an adult female Iberian wolf (Canis lupus signatus) in central Spain. Nematodes collected were morphologically identified (n = 42), and two specimens were molecularly characterized. At the sequence analysis of the partial mitochondrial cytochrome c oxidase subunit 1 gene, T. callipaeda haplotype 1 (the only haplotype circulating in Europe) was detected. The role of the Iberian wolf as a natural reservoir for T. callipaeda in the life cycle of this emerging zoonosis and the implications in conservation are discussed.


Assuntos
Olho/parasitologia , Infecções por Spirurida/veterinária , Thelazioidea/isolamento & purificação , Lobos/parasitologia , Animais , Vetores de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/genética , Europa (Continente) , Feminino , Genes Mitocondriais/genética , Haplótipos/genética , Humanos , Masculino , Espanha , Thelazioidea/genética , Zoonoses/parasitologia
14.
Parasitol Res ; 119(7): 2085-2091, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32458117

RESUMO

The present study aims to perform comparative genetic characterization for R. sanguineus s.l. infesting Algerian dogs living in steppe and high plateau regions based on mitochondrial 16S rRNA gene sequencing and phylogenetic analysis. In total, 1043 ticks were collected from 147 infested dogs, including 756 ticks from 124 dogs in Djelfa and 287 ticks from 23 dogs in Bordj-Bou-Arreridj. All ticks were morphologically identified as R. sanguineus s.l., and 87 specimens were randomly selected for molecular analysis. Sequences obtained from selected ticks clustered with sequences of R. sanguineus s.l. from France, Germany, Portugal, and Spain, all of which belong to R. sanguineus s.s. The occurrence of R. sanguineus s.s. in Algeria is an interesting result given that most R. sanguineus in Africa cluster among the tropical lineage. This finding should prompt further investigation by exhaustive studies across Algerian territory. Such data can be useful to understand the dispersal route of R. sanguineus s.s. from Europe to North Africa, or whether their occurrence in Algeria is a result of historical biogeography.


Assuntos
Genes Mitocondriais/genética , Filogenia , RNA Ribossômico 16S/genética , Rhipicephalus sanguineus/classificação , Rhipicephalus sanguineus/genética , Argélia , Animais , Doenças do Cão/parasitologia , Cães , Europa (Continente)
15.
PLoS One ; 15(4): e0231009, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240264

RESUMO

Our study is focused on original and publicly accessible data on the intraspecific variability of the barcoding DNA fragment in ladybirds Harmonia axyridis Pall analysis. The complete dataset consists of 39 haplotypes, 16 of which we identified for the first time. The intra-population and geographical variability of the barcoding fragment was studied for seven populations of the western and eastern groups of the native range and in six invasive populations, in which 25 of the 39 haplotypes are found. Population structure inferred on base of molecular variability and haplotype frequencies showed a high level of differences between the eastern and western groups of native populations and confirm the hypothesis of the origin of all invasive populations from native populations of the eastern group. A comparative analysis of molecular variation indices testifies to various evolutionary scenarios of the formation of the western and eastern groups of native populations and confirms the hypothesis of the microevolutionary history of the species, previously suggested in morphological character based studies of the geographical variability of H. axyridis. A significant decrease in the molecular diversity of invasive populations confirms the hypothesis of a random nature of the primary invasion of this species in North America.


Assuntos
Besouros/genética , Genes Mitocondriais/genética , Variação Genética/genética , Animais , Evolução Biológica , Genética Populacional/métodos , Haplótipos/genética , Espécies Introduzidas , América do Norte
16.
Artigo em Inglês | MEDLINE | ID: mdl-32126856

RESUMO

The family Bagridae is a collection of species widely distributed in Africa and Asia with a high diversity of morphology. The species identification and phylogenetic relationship in this family have been confused and controversial. In order to explore the effectiveness of DNA barcoding in species identification of Bagridae, sequences of mitochondrial cytochrome c oxidase I (COI) gene of 20 species in four genera of Bagridae were used to analyse barcoding gap and to reconstruct phylogenetic relationship. Both the barcoding gap and the phylogenetic tree analysis showed that the COI gene-based DNA barcoding is an effective molecular technique for most species recognition of Chinese Bagridae. However, the rapid speciation and incomplete lineage sorting may affect the accuracy of DNA barcoding in species identification in certain species, and adding additional genes, such as nuclear gene, may help to achieve accurate identification of these species. The phylogenetic tree showed that the monophyly of genera Pelteobagrus, Leiocassis and Pseudobagrus did not exist, which supports that the species of genera Pelteobagrus, Pseudobagrus and Leiocassis distributed in China should be revised into one genus.


Assuntos
Peixes-Gato/classificação , Peixes-Gato/genética , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais/genética , Genoma Mitocondrial/genética , Animais , China , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Filogenia
17.
J Fish Biol ; 96(6): 1360-1369, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32112652

RESUMO

Limia islai, a new species of livebearing fish, is described from Lake Miragoane in south-western Haiti on Hispaniola. The new species has a conspicuous barred pattern consisting of several (4-12) black bars along the body, ray 4p serrae of the gonopodium in males with 10 segments and origin of dorsal fin in females slightly behind the origin of the anal fin. Although the new species colour pattern is similar to that of the humpbacked limia Limia nigrofasciata Regan 1913, L. islai sp. nov. has exclusive morphological features, such as slender body, lack of hump anterior to dorsal fin in males and presence of specific features in the gonopodial suspensory, which allow an unambiguous diagnosis from L. nigrofasciata. L. islai further differs from L. nigrofasciata in reproductive behaviour since L. islai males rely on sneak copulations and gonopodial thrusting, whereas L. nigrofasciata display an elaborate courtship behaviour. The new species is also genetically distinct in both nuclear (Rh, Myh6) and mitochondrial (12S, ND2, D-loop, Cytb) genes from other species in the genus showing reciprocal monophyly. The description of this new Limia species from Lake Miragoane confirms this lake as an important centre of endemism for the genus, with a total of eight endemic species described so far.


Assuntos
Ciprinodontiformes/classificação , Nadadeiras de Animais/anatomia & histologia , Animais , Ciprinodontiformes/anatomia & histologia , Ciprinodontiformes/genética , Feminino , Proteínas de Peixes/genética , Genes Mitocondriais/genética , Haiti , Lagos , Masculino , Pigmentação , Comportamento Sexual Animal , Especificidade da Espécie
18.
Mitochondrial DNA A DNA Mapp Seq Anal ; 31(3): 98-107, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32186219

RESUMO

South China presents an excellent opportunity to build a phylogeographic paradigm for complex geological history, including mountain lifting, climate change, and river capture/reversal events. The phylogeography of cyprinids, particularly Opsariichthys hainanensis, an endemic species restricted to South China, was examined to explore the relationship between the populations in Red River, Hainan Island and its adjacent mainland China. A total of 37 haplotypes were genotyped for the mitochondrial cytochrome b (Cyt b) gene in 115 specimens from 11 river systems. Relatively high levels of haplotype diversity (h = 0.946) and low levels of nucleotide diversity (π = 0.014) were detected in O. hainanensis. Four major phylogenetic haplotype groups revealed a relationship between phylogeny and geography. Our results found that (i) the ancestral populations of O. hainanensis were distributed south of the Wuzhishan and Yinggeling mountains, including the Changhua River on Hainan Island, and then spread to the surrounding areas, (ii) the admixtures within lineages occurred between the Red River in North Vietnam and the Changhua River in western Hainan Island and (iii) indicated that the exposure of straits and shelves under water retreat, provides opportunities for population dispersion during glaciations.


Assuntos
Cyprinidae/genética , Citocromos b/genética , Animais , China , DNA Mitocondrial/genética , Peixes/genética , Genes Mitocondriais/genética , Estruturas Genéticas/genética , Variação Genética/genética , Genética Populacional/métodos , Genoma Mitocondrial/genética , Haplótipos/genética , Mitocôndrias/genética , Filogenia , Filogeografia , Rios , Análise de Sequência de DNA/métodos
19.
J Helminthol ; 94: e138, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32188515

RESUMO

A new species of Moniliformis Travassos, 1915 (Acanthocephala: Moniliformidae) is described from the hairy-tailed bolo mouse, Necromys lasiurus Lund, 1840 (Cricetidae: Sigmondontinae), captured in the Brazilian Cerrado, in Uberlândia, state of Minas Gerais, Brazil. The specimens were studied by light and scanning electron microscopy. Molecular phylogenies were inferred from partial nuclear large subunit ribosomal RNA gene sequences and partial mitochondrial cytochrome c oxidase subunit I gene. The new species is distinguished from other moniliformid species by the number of rows and number of hooks per row, size of the proboscis, size of the eggs, host species and geographical distribution. Molecular phylogenies and genetic distances analyses demonstrated that Moniliformis necromysi sp. n. forms a well-supported monophyletic group with sequences of other species of Moniliformis and is distinguished from them, which agrees with the morphological characteristics, allocating the new species to this genus and to the family Moniliformidae Van Cleave, 1924. This is the first moniliformid acanthocephalan described from a wild rodent in Brazil.


Assuntos
Moniliformis/classificação , Moniliformis/ultraestrutura , Sigmodontinae/parasitologia , Animais , Brasil , Feminino , Genes Mitocondriais/genética , Masculino , Microscopia Eletrônica de Varredura , Filogenia , RNA Ribossômico/genética
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 31(3): 120-130, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32212876

RESUMO

To understand the genetic diversity and dispersal history of Schlegel's Japanese gecko (Gekko japonicus), we performed genetic analyses and paleo-species distributional modelling. For the genetic analysis, we analyzed mitochondrial DNA (mtDNA) (cytochrome b [Cytb] and NADH dehydrogenase 2 [ND2]) and seven microsatellite loci of 353 individuals from 11 populations (2 east coast China, 4 west and central coast Japan and 5 Korea). For the paleo-species distribution modelling, we used 432 occurrence data points (125 China, 291 Japan and 16 Korea) over the Pleistocene and Holocene. China is inferred to be the source population, which had higher genetic diversity (mtDNA) and more private alleles (mtDNA) compared to Japanese and Korean populations. Differences between the three counties were very small in the mtDNA haplotype network despite some genetic structure among the three countries. Microsatellite analysis inferred that genetic exchange has actively occurred among the Chinese, Japanese and Korean populations. Suitable habitats in Japan should have been plentiful by the mid-Holocene, but have only recently become available in Korea. These results suggest that dispersal of G. japonicus occurred after the Holocene warming from the east coast of China to the west and central coasts of Japan and Korea, and gene flow is actively occurring among the three countries.


Assuntos
Citocromos b/genética , Lagartos/genética , NADH Desidrogenase/genética , Alelos , Animais , China , DNA Mitocondrial/genética , Ecossistema , Genes Mitocondriais/genética , Variação Genética/genética , Genética Populacional/métodos , Genoma Mitocondrial/genética , Haplótipos/genética , Japão , Repetições de Microssatélites/genética , Mitocôndrias/genética , Filogenia , Filogeografia/métodos , República da Coreia , Análise de Sequência de DNA/métodos
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