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1.
Life Sci ; 264: 118695, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33130079

RESUMO

AIMS: Maternal nicotine exposure during pregnancy and lactation is associated with obesity in offspring. Brown adipose tissue (BAT) is correlated with energy metabolism and obesity. In this study, we explored the mechanism of maternal nicotine exposure on BAT changes in male offspring. MAIN METHODS: Pregnant rats were randomly assigned to nicotine (1.0 mg/kg twice per day, subcutaneous administration) or control groups. In vitro, C3H10T1/2 cells were induced to differentiate into mature brown adipocytes, and 0-50 µM nicotine was given to C3H10T1/2 cells during the differentiation process. KEY FINDINGS: Nicotine-exposed males had white-like adipocytes and abnormal mitochondria structure in iBAT at 26 weeks. The expression of mitochondrial genes, UCP1 and AMPK-SIRT1-PGC-1α pathway were downregulated in the nicotine group at 26 weeks rather than 4 weeks. In vitro, 50 µM nicotine decreased the expression of mitochondrial genes, UCP1 and AMPK-SIRT1-PGC-1α pathway in brown adipocytes. SIGNIFICANCE: Maternal nicotine exposure showed the "programming" effect on the decreased brown-like phenotype in BAT of adult male offspring via downregulating AMPK-SIRT1-PGC-1α pathway. This impairment of BAT may be a potential mechanism of nicotine-induced obesity in male offspring.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo Marrom/metabolismo , Nicotina/efeitos adversos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Transdução de Sinais , Sirtuína 1/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Marrom/ultraestrutura , Animais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Mitocondriais , Masculino , Gravidez , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Proteína Desacopladora 1/metabolismo
2.
Zootaxa ; 4878(2): zootaxa.4878.2.7, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33311158

RESUMO

A new species of hill-stream loach, Indoreonectes telanganaensis, is described from a seasonal tributary of the Godavari River at Maisamma Loddi, within the Kawal Tiger Reserve, Telangana State, India. The new species is distinguished from its congeners by a combination of characters including caudal peduncle as long as deep; eye large, its diameter about one-fifth head length; pectoral fin as long as head; nasal barbel reaching the middle of the eye; dorsal-fin origin on vertical through pelvic-fin origin; and bars on the lateral side of the body well defined and wide. We also provide multivariate morphometric, and DNA analysis based on the mitochondrial cytochrome b gene sequence to support the distinction of the new species.


Assuntos
Cipriniformes , Animais , Genes Mitocondriais , Cabeça , Índia , Rios
3.
Zootaxa ; 4877(3): zootaxa.4877.3.11, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311186

RESUMO

In a recent article, Chandramouli et al. (2020) re-assessed the systematic position of the hylaranine frog Indosylvirana nicobariensis and proposed a new monotypic genus, Bijurana, for this species. The authors re-examined the type series of specimens and attempted to justify the recognition of a new genus using morphological and phylogenetic data. They concluded that the taxon's unique phylogenetic position, high genetic divergence (uncorrected p-distance ≥ 13.64% of the 16S rRNA mitochondrial gene), and a unique combination of morphological characters warranted the erection of the new genus.


Assuntos
Anuros , Genes Mitocondriais , Animais , Anuros/genética , Filogenia , RNA Ribossômico 16S
4.
PLoS One ; 15(11): e0242541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33253261

RESUMO

Phymorhynchus is a genus of deep-sea snails that are most distributed in hydrothermal vent or cold seep environments. In this study, we presented the complete mitochondrial genome of P. buccinoides, a cold seep snail from the South China Sea. It is the first mitochondrial genome of a cold seep member of the superfamily Conoidea. The mitochondrial genome is 15,764 bp in length, and contains 13 protein-coding genes (PCGs), 2 rRNA genes, and 22 tRNA genes. These genes are encoded on the positive strand, except for 8 tRNA genes that are encoded on the negative strand. The start codon ATG and 3 types of stop codons, TAA, TAG and the truncated termination codon T, are used in the 13 PCGs. All 13 PCGs in the 26 species of Conoidea share the same gene order, while several tRNA genes have been translocated. Phylogenetic analysis revealed that P. buccinoides clustered with Typhlosyrinx sp., Eubela sp., and Phymorhynchus sp., forming the Raphitomidae clade, with high support values. Positive selection analysis showed that a residue located in atp6 (18 S) was identified as the positively selected site with high posterior probabilities, suggesting potential adaption to the cold seep environment. Overall, our data will provide a useful resource on the evolutionary adaptation of cold seep snails for future studies.


Assuntos
Genoma Mitocondrial , Caramujos/genética , Animais , DNA Mitocondrial/genética , Ordem dos Genes , Genes Mitocondriais , Proteínas Mitocondriais/genética , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética
5.
Zootaxa ; 4861(1): zootaxa.4861.1.3, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33055868

RESUMO

The Music Frog genus Nidirana was recently resurrected as a distinct genus and contains 14 species distributed in subtropical eastern and southeastern Asia. The species diversity of Nidirana is dramatically underestimated, and half of its species was described in the last five years. In this study, Nidirana occidentalis sp. nov., a new species of Music Frog from western Yunnan, China, is proposed based on morphological and molecular evidences. The new species was previously misidentified as N. pleuraden, but can be distinguished from the true N. pleuraden from eastern Yunnan, and all other congeners, by a combination of morphological characteristics, and significant divergence in the mitochondrial genes (≥ 5.1% in 16S and ≥ 8.9% in CO1). Nidirana occidentalis sp. nov. is assigned to the N. pleuraden group on the basis of morphological characters, but its phylogenetic placement remains unresolved due to weak branch support. Geographically, these two species are isolated by the Red River in Yunnan, supporting the hypothesis that the Red River is an important geographical barrier that drives speciation in flora and fauna. Nidirana occidentalis sp. nov. represents the second species of N. pleuraden group and the 15th species of the genus.


Assuntos
Anuros , Ranidae , Animais , China , Genes Mitocondriais , Filogenia
6.
Zootaxa ; 4852(4): zootaxa.4852.4.1, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-33056404

RESUMO

A new gekkonid lizard, Cyrtodactylus maelanoi sp. nov., from Mae Hong Son Province of the Thai Highlands is described using an integrative taxonomic analysis based on morphology, color pattern, and the mitochondrial gene NADH dehydrogenase subunit 2 (ND2) and its flanking tRNAs. Phylogenetic analyses place the new species within clade 1 of the C. sinyineensis group and as the sister species to C. inthanon with an uncorrected pairwise sequence divergence of 3.9%. Collection data gathered in the field indicate that C. maelanoi sp. nov. is a habitat generalist. Reconstruction of the ancestral habitat preference for the C. sinyineensis group by way of stochasitc character mapping (SCM) indicates that karstic environments were the ancestral condition out of which the general habitat preference of the ancestor of C. maelanoi sp. nov. and C. inthanon and that of C. amphipetreaus and C. doisuthep evolved three times independently. Additionally, SCM demonstrated that the evolution of a granitic habitat preference from a karst-adapted ancestor happened in C. aequalis. The discovery of a new upland species in the Thai Highlands brings into focus the understudied nature of the mountain systems of western Thailand and the need for their continued exploration and conservation.


Assuntos
Lagartos , Animais , Ecossistema , Genes Mitocondriais , Filogenia , Tailândia
7.
Zootaxa ; 4811(1): zootaxa.4811.1.1, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-33055724

RESUMO

The planthopper genus Chionomus Fennah, 1971 (Hemiptera: Fulgoroidea: Delphacidae) currently includes three Neotropical species, removed from the polyphyletic genus Delphacodes Fieber, 1866. Morphological and molecular evidence further redefine Chionomus to include ten additional species (eight species removed from Delphacodes, two described as new, viz. Chionomus dolonus n. sp. and C. herkos n. sp.), with another four species synonymized. Phylogenetic analyses of morphological and molecular sequence data of the mitochondrial gene Cytochrome Oxidase I provide support for the monophyly of Chionomus. We use a mixed model Bayesian optimality criterion to define phylogenetic relationships among Chionomus and support paraphyly of the original definition of Chionomus (with respect to Delphacodes) and monophyly of the revised genus.


Assuntos
Hemípteros , Animais , Teorema de Bayes , Genes Mitocondriais , Dados de Sequência Molecular , Filogenia
8.
Zootaxa ; 4852(2): zootaxa.4852.2.6, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33056426

RESUMO

Five species of geckos in the genus Goniurosaurus had been recorded from Guangxi, China. Here we describe a new species, Goniurosaurus gezhi sp. nov. Zhu, He Li. The new species is similar to those found in Guangxi and Guizhou provinces of China and Northern Vietnam, but unique in a combination of the following characters: (1) three body bands between limb insertions; (2) precloacal pores 18-20; (3) body small (SVL=70.6-83.8 mm); (4) body color orange to yellow. We evaluated the phylogenetic position of this new species based on the 16S mitochondrial gene. Molecular phylogenies validate this new species as distinct to currently described lineages within Goniurosaurus. The type specimens are deposited in the Museum of Biology, East China Normal University (ECNU).


Assuntos
Lagartos , Animais , China , Genes Mitocondriais , Masculino , Filogenia
9.
Zootaxa ; 4838(2): zootaxa.4838.2.2, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-33056821

RESUMO

A new species of Cyrtodactylus from Tak Province, Thailand, Cyrtodactylus amphipetraeus sp. nov., is described using an integrative taxonomic analysis based on morphology, color pattern, and the mitochondrial gene NADH dehydrogenase subunit 2 (ND2). The phylogenetic analyses place the new species within the C. sinyineensis group which was previously thought to be endemic to the Salween Basin in southern Myanmar. The phylogeny also places C. inthanon in the C. sinyneensis group which is expanded herein to also include the group's sister species C. doisuthep. Along with C. amphipetraeus sp. nov., these are the first three species of the C. sinyineensis group to be found outside of Myanmar east of the Tenasserim Mountains. The Tenasserim Mountain region is discussed as an area of cladogeneic turnover.


Assuntos
Lagartos , Animais , Genes Mitocondriais , Filogenia , Tailândia
10.
Zootaxa ; 4772(2): zootaxa.4772.2.2, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33055612

RESUMO

A taxonomic study on bdelloid rotifers collected from various terrestrial habitats at five different locations in Korea resulted in eight new Korean records and two new species-level taxa, Philodina clypeata  n. sp. and P. verrucosa  n. sp. Among the eight new Korean records, two species- and three subspecies-level taxa are new to Asia as well. These new Korean records also include seven rare species/subspecies-level taxa with poorly known distributions. Habrotrocha gracilis quadridens Schulte and Macrotrachela zickendrahti seda Donner were rediscovered in Korea 64 and 53 years, respectively, after the original descriptions. Habrotrocha ligula aligula Burger, Macrotrachela insulana Donner, M. petulans Milne, M. pinnigera (Murray), and Philodina parvicalcar De Koning have been reported from two to three countries only including their type localities before the present study. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit I gene (mtCOX1) for P. verrucosa  n. sp. as well as a taxonomic key for the Philodina species recorded from Korea to date are also provided here.


Assuntos
Rotíferos , Animais , Ecossistema , Genes Mitocondriais , República da Coreia
11.
Sci Rep ; 10(1): 16500, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020532

RESUMO

Taiwanofungus camphoratus is a highly valued medicinal mushroom that is endemic to Taiwan, China. In the present study, the mitogenome of T. camphoratus was assembled and compared with other published Polyporales mitogenomes. The T. camphoratus mitogenome was composed of circular DNA molecules, with a total size of 114,922 bp. Genome collinearity analysis revealed large-scale gene rearrangements between the mitogenomes of Polyporales, and T. camphoratus contained a unique gene order. The number and classes of introns were highly variable in 12 Polyporales species we examined, which proved that numerous intron loss or gain events occurred in the evolution of Polyporales. The Ka/Ks values for most core protein coding genes in Polyporales species were less than 1, indicating that these genes were subject to purifying selection. However, the rps3 gene was found under positive or relaxed selection between some Polyporales species. Phylogenetic analysis based on the combined mitochondrial gene set obtained a well-supported topology, and T. camphoratus was identified as a sister species to Laetiporus sulphureus. This study served as the first report on the mitogenome in the Taiwanofungus genus, which will provide a basis for understanding the phylogeny and evolution of this important fungus.


Assuntos
Rearranjo Gênico/genética , Genoma Mitocondrial/genética , Íntrons/genética , Polyporales/genética , Agaricales/genética , Evolução Molecular , Ordem dos Genes/genética , Genes Mitocondriais/genética , Filogenia , Taiwan
12.
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
13.
PLoS One ; 15(9): e0233666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970680

RESUMO

Mitochondrial DNA variants associated with diseases are widely studied in contemporary populations, but their prevalence has not yet been investigated in ancient populations. The publicly available AmtDB database contains 1443 ancient mtDNA Eurasian genomes from different periods. The objective of this study was to use this data to establish the presence of pathogenic mtDNA variants putatively associated with mitochondrial diseases in ancient populations. The clinical significance, pathogenicity prediction and contemporary frequency of mtDNA variants were determined using online platforms. The analyzed ancient mtDNAs contain six variants designated as being "confirmed pathogenic" in modern patients. The oldest of these, m.7510T>C in the MT-TS1 gene, was found in a sample from the Neolithic period, dated 5800-5400 BCE. All six have well established clinical association, and their pathogenic effect is corroborated by very low population frequencies in contemporary populations. Analysis of the geographic location of the ancient samples, contemporary epidemiological trends and probable haplogroup association indicate diverse spatiotemporal dynamics of these variants. The dynamics in the prevalence and distribution is conceivably result of de novo mutations or human migrations and subsequent evolutionary processes. In addition, ten variants designated as possibly or likely pathogenic were found, but the clinical effect of these is not yet well established and further research is warranted. All detected mutations putatively associated with mitochondrial disease in ancient mtDNA samples are in tRNA coding genes. Most of these mutations are in a mt-tRNA type (Model 2) that is characterized by loss of D-loop/T-loop interaction. Exposing pathogenic variants in ancient human populations expands our understanding of their origin and prevalence dynamics.


Assuntos
DNA Antigo , DNA Mitocondrial/genética , Genes Mitocondriais , Doenças Mitocondriais/genética , Bases de Dados Genéticas , Feminino , Humanos , Masculino , Mitocôndrias/genética , Mutação , RNA de Transferência/genética
14.
PLoS One ; 15(9): e0237160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881879

RESUMO

Pareiorhaphis hystrix is a widely distributed species, occurring in the upper and middle Uruguay River and in the Taquari River basin, Patos Lagoon system, southern Brazil. Morphological variation has been detected throughout the distribution of P. hystrix, and this work seeks to test the conspecific nature of populations in several occurrence areas. Specimens from six areas in the Uruguay River basin and three in the Taquari River basin were compared. Variance analysis (ANOVA) was performed for the meristic data, and Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were conducted for morphometric data. Molecular analyses used coI, cytb, 12S and 16S mitochondrial genes, examining nucleotide diversity, haplotype diversity, genetic distance, and delimitation of possible multiple species through the Generalized Mixed Yule Coalescent (GMYC) method. Phylogenetic relationships of studied populations were also investigated through Bayesian inference. While PCA indicated a tendency of overlap between areas, ANOVA and LDA detected a subtle differentiation between populations from the two hydrographic basins. Yet, both latter analyses recovered the population from Pelotas River, a tributary to Uruguay River, as more similar to populations from Taquari River, which is congruent to morphological observations of anterior abdominal plates. The molecular data indicated a nucleotide diversity lower than the haplotypic diversity, suggestive of recent expansion. The concatenated haplotype network points to slight differentiation between areas, with each locality presenting unique and non-shared haplotypes, although with few mutational steps in general. The species delimitation by coalescence analysis suggested the presence of a variable number of OTUs depending on the inclusion or exclusion of an outgroup. In general, the morphological data suggest a subtle variation by river basin, while the genetic data indicates a weak population structuration by hydrographic areas, especially the Chapecó and Passo Fundo rivers. However, there is still not enough differentiation between the specimens to suggest multiple species. The iterative analyses indicate that Pareiorhaphis hystrix is composed of a single, although variable, species.


Assuntos
Peixes-Gato/anatomia & histologia , Peixes-Gato/classificação , Animais , Teorema de Bayes , Brasil , Peixes-Gato/genética , Análise Discriminante , Feminino , Genes Mitocondriais , Geografia , Haplótipos/genética , Masculino , Fenótipo , Filogenia , Pigmentação , Análise de Componente Principal , Rios , Especificidade da Espécie
15.
PLoS One ; 15(9): e0239143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941478

RESUMO

Feed efficiency (FE) is a key trait in pig production, as improvement in FE has positive economic and environmental impact. FE is a complex phenotype and testing animals for FE is costly. Therefore, there has been a desire to find functionally relevant single nucleotide polymorphisms (SNPs) as biomarkers, to improve our biological understanding of FE as well as accuracy of genomic prediction for FE. We have performed a cis- and trans- eQTL (expression quantitative trait loci) analysis, in a population of Danbred Durocs (N = 11) and Danbred Landrace (N = 27) using both a linear and ANOVA model based on muscle tissue RNA-seq. We analyzed a total of 1425x19179 or 2.7x107 Gene-SNP combinations in eQTL detection models for FE. The 1425 genes were from RNA-Seq based differential gene expression analyses using 25880 genes related to FE and additionally combined with mitochondrial genes. The 19179 SNPs were from applying stringent quality control and linkage disequilibrium filtering on genotype data using a GGP Porcine HD 70k SNP array. We applied 1000 fold bootstrapping and enrichment analysis to further validate and analyze our detected eQTLs. We identified 13 eQTLs with FDR < 0.1, affecting several genes found in previous studies of commercial pig breeds. Examples include MYO19, CPT1B, ACSL1, IER5L, CPT1A, SUCLA2, CSRNP1, PARK7 and MFF. The bootstrapping results showed statistically significant enrichment (p-value<2.2x10-16) of eQTLs with p-value < 0.01 in both cis and trans-eQTLs. Enrichment analysis of top trans-eQTLs revealed high enrichment for gene categories and gene ontologies associated with genomic context and expression regulation. This included transcription factors (p-value = 1.0x10-13), DNA-binding (GO:0003677, p-value = 8.9x10-14), DNA-binding transcription factor activity (GO:0003700,) nucleus gene (GO:0005634, p-value<2.2x10-16), negative regulation of expression (GO:0010629, p-value<2.2x10-16). These results would be useful for future genome assisted breeding of pigs to improve FE, and in the improved understanding of the functional mechanism of trans eQTLs.


Assuntos
Cruzamento , Locos de Características Quantitativas , Sus scrofa/genética , Transcriptoma , Criação de Animais Domésticos , Animais , Dinamarca , Genes Mitocondriais , Masculino , Músculos/metabolismo , Polimorfismo de Nucleotídeo Único
16.
Nat Commun ; 11(1): 4603, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929079

RESUMO

Amino acid propensities at a site change in the course of protein evolution. This may happen for two reasons. Changes may be triggered by substitutions at epistatically interacting sites elsewhere in the genome. Alternatively, they may arise due to environmental changes that are external to the genome. Here, we design a framework for distinguishing between these alternatives. Using analytical modelling and simulations, we show that they cause opposite dynamics of the fitness of the allele currently occupying the site: it tends to increase with the time since its origin due to epistasis ("entrenchment"), but to decrease due to random environmental fluctuations ("senescence"). By analysing the genomes of vertebrates and insects, we show that the amino acids originating at negatively selected sites experience strong entrenchment. By contrast, the amino acids originating at positively selected sites experience senescence. We propose that senescence of the current allele is a cause of adaptive evolution.


Assuntos
Aminoácidos/genética , Evolução Molecular , Alelos , Sequência de Aminoácidos , Animais , Simulação por Computador , Meio Ambiente , Genes Mitocondriais , Aptidão Genética , Heterogeneidade Genética , Insetos/genética , Seleção Genética , Vertebrados/genética
17.
Mol Phylogenet Evol ; 153: 106949, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32866614

RESUMO

Gall wasps in the genus Diplolepis Geoffroy are specialized herbivores that induce galls exclusively on roses. Despite their wide distribution across the Holarctic, little is known about their evolutionary history. Here we present the first phylogenomic tree of global Diplolepis reconstructed using Ultraconserved Elements (UCEs), resulting in a robust phylogeny based on 757 genes. Results support the existence of two principal clades: a Nearctic stem-galler clade, and a Holarctic leaf-galler clade that further splits into two Palearctic groups and one Nearctic group. This topology is congruent with a previous study based on the mitochondrial gene COI, an unexpected result given the common occurrence of mitonuclear discordance in closely related oak gall wasp lineages. Most Diplolepis species were recovered as reciprocally monophyletic, with some notable exceptions such as the D. polita and the D. ignota complex, for which species boundaries remain unresolved. Historical biogeographic reconstruction was unable to pinpoint the origin of Diplolepis, but confirms two independent incursions into the Nearctic. Ancestral state reconstruction analysis highlights the conservatism of gall location on the host plants, as shifts to different host organs are relatively rare. We suggest that Diplolepis were originally leaf gallers, with a Nearctic stem-galler clade undergoing a major plant organ switch onto rose stems. Host organ switch or reversal is uncommon, which suggests a level of conservatism. Our study showcases the resolving power of UCEs at the species level while also suggesting improvements to advance future Cynipoidea phylogenomics. Our results also highlight the additional sampling needed to clarify taxonomic relationships in the Nearctic and eastern Palearctic regions.


Assuntos
Filogenia , Vespas/classificação , Vespas/genética , Animais , Sequência Conservada/genética , Genes Mitocondriais/genética , América do Norte , Rosa/parasitologia
18.
Mol Phylogenet Evol ; 153: 106950, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32889137

RESUMO

Cryptic species describe two or more species that had mistakenly been considered to be a single species, a phenomenon that has been found throughout the tree of life. Recognizing cryptic species is key to estimating the real biodiversity of the world and understanding evolutionary processes. Molecular methods present an unprecedented opportunity for biologists to question whether morphologically similar populations are actually cryptic species. The minnow Tanichthys albonubes is a critically endangered freshwater fish and was classified as a second-class state-protected animal in China. Previous studies have revealed highly divergent lineages with similar morphological characters in this species. Herein, we tested for cryptic species across the ranges of all known wild populations of this minnow. Using multilocus molecular (one mitochondrial gene, two nuclear genes and 13 microsatellite loci) and morphological data for 230 individuals from eight populations, we found deep genetic divergence among these populations with subtle morphological disparity. Morphological examination found variance among these populations in the number of branched anal-fin rays. Based on genetic data, we inferred eight monophyletic groups that were well supported by haplotype network and population clustering analyses. Species delimitation methods suggested eight putative species in the T. albonubes complex. Molecular dating suggested that these cryptic species diverged in the period from the Pliocene to the Pleistocene. Based on these findings, we propose the existence of seven cryptic species in the T. albonubes complex. Our results highlight the need for a taxonomic revision of Tanichthys. What is more, the conservation status of and conservation strategies for the T. albonubes complex should be reassessed as soon as possible.


Assuntos
Cyprinidae/classificação , Especiação Genética , Filogenia , Animais , China , Conservação dos Recursos Naturais , Cyprinidae/genética , Genes Mitocondriais/genética , Repetições de Microssatélites/genética , Especificidade da Espécie
19.
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
20.
Sci Rep ; 10(1): 15438, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963308

RESUMO

The Indian black clam Villorita cyprinoides (Family: Cyrenidae), an extractive commercially exploited species with aquaculture importance contributing more than 70% of clam fishery in India, is endemic to the Indian peninsula. Currently, there is very sparse information, especially on the molecular data of Villorita. The present study aims to provide a comprehensive knowledge of mitogenome architecture and assess the phylogenetic status of Cyrenidae. This has resulted in reporting the first complete mitogenome of V. cyprinoides using next-generation sequencing technology. The A+T circular mitogenome was 15,880 bp long, exhibiting 13 protein-coding genes (PCGs) including ATP8 (absent in several bivalves), 22 transfer RNA, and two ribosomal RNA genes residing in the heavy strand in a clockwise orientation and a gene order akin to Corbicula fluminea. The molecular phylogeny inferred from a concatenated multi-gene sequence [14 mitochondrial (12 PCGs, rrnS and rrnL) and two nuclear genes (Histone H3, 18S rRNA)] from 47 representative species of superorder Imparidentia, clustered V. cyprinoides and Cyrenid clams to a single clade supporting the monophyly of Cyrenidae. The subsequent mitochondrial gene order analysis substantiates the close relationship of V. cyprinoides and C. fluminea, analogous to phylogenetic output. The multilocus tree topology calibrated with verified fossil data deciphered the origin and diversification of Cyrenid clams during late Triassic-early Jurassic. The data derived from this study shall contribute remarkably for further insights on cryptic species identification, molecular characterization of bivalve mitogenomes and mitochondrial evolutionary history of genus Villorita. Moreover, complete mitogenome can aid in potential marker development for assessing the genetic health of black clam populations.


Assuntos
Evolução Biológica , Bivalves/genética , DNA Mitocondrial/análise , Genes Mitocondriais , Genoma Mitocondrial , Filogenia , Animais , DNA Mitocondrial/genética , Ordem dos Genes , Rearranjo Gênico , Sequenciamento de Nucleotídeos em Larga Escala
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