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1.
Exp Appl Acarol ; 83(4): 493-511, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33813665

RESUMO

Oribatid mites are important decomposers of dead organic matter in soils across the world. Their origin dates back at least 380 Mya. Multiple severe climatic changes during Late Pliocene and Pleistocene shaped the migration patterns of these organisms and should be reflected in the genetic variability of their current populations. In this study, we examined the genetic diversity and phylogeographic structure as well as the evolutionary history of populations of two ecologically different oribatid mite species. Pantelozetes cavaticus is a troglophile oribatid mite known mainly from Central European caves, whereas Pantelozetes paolii is a common surface eurytopic species with Holarctic distribution. We used two molecular markers-mitochondrial cytochrome c oxidase subunit I (COI) and the nuclear D3 region of the 28S rDNA gene-to reveal phylogenetic relationships between contemporary populations. Whereas the D3 region showed minimal or no variability within populations, COI appeared to be a relevant marker for population studies. Phylogeographic analysis based on COI detected two lineages of P. cavaticus ('Czech' and 'Slovak'), which separated during the Late Pliocene (2.9 Mya) and revealed the existence of one new species. In contrast, three identified genetic lineages of P. paolii (radiation time 2.9 and 1.2 Mya, respectively) uncovered in this study were found to coexist in the distant sampling localities, suggesting a connection between populations even over long distances.


Assuntos
Ácaros , Animais , DNA Ribossômico , Europa (Continente) , Ácaros/genética , Filogenia , Filogeografia
2.
J Med Entomol ; 58(1): 246-251, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33432352

RESUMO

A parasitic outbreak caused by dermanyssoid mites in a herpetarium of the Metropolitan area of the Valley of Mexico is revealed. This outbreak was caused by Hemilaelaps triangulus (Ewing), but a second mite species, Ophionyssus natricis (Gervais), was found in low abundance. The parasitic load is analyzed, and the morphological and molecular diagnostic characters to identify each of the two species involved are given. A barcode analysis is presented, and two more molecular markers are presented and analyzed. Hemilaelaps triangulus is recorded for the first time in Mexico, and this is the first record of massive infestation on captive snakes caused by ixodorhynchid mites, and DNA sequences of ixodorhynchid mites are publicly available for the first time.


Assuntos
Surtos de Doenças/veterinária , Infestações por Ácaros/veterinária , Ácaros/classificação , Serpentes , Animais , México/epidemiologia , Infestações por Ácaros/classificação , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/parasitologia , Ácaros/anatomia & histologia , Ácaros/genética , Ácaros/fisiologia
3.
Gene ; 756: 144911, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32574756

RESUMO

Enolase, a multifunctional glycolytic enzyme, is known to act as a plasminogen receptor in many species, involved in the pivotal processes such as motility, adhesion, invasion, growth, and differentiation of the parasites. Knowledge on the function of enolase from Dermanyssus gallinae is very limited. Here we report on the molecular cloning, enzymatic activity, tissue distribution and plasminogen binding activity of enolase from D. gallinae (DgENO). The full-length of cDNA was 1305 bp, specifying a peptide of 434 amino acids. Bioinformatics analysis showed that DgENO was highly conserved compared with a range of organisms, indicating the potentially similar functions in D. gallinae. A recombinant DgENO (rDgENO) protein was produced and characterized, it catalyzed the dehydration of 2-phospho-D-glycerate to phosphoenolpyruvate, the optimal pH was 7.5. Polyclonal antibodies were generated in mice and western blotting indicated that antiserum specifically recognized the native enolase in the somatic extracts from D. gallinae. Immunohistochemical staining of mite sections revealed that the distribution of DgENO was ubiquitous with high level in salivary gland, mite digestive tissues and fat bodies in D. gallinae. Expression level of DgENO was observed mostly in engorged adult mites. Moreover, ELISA binding assay showed that rDgENO could bind plasminogen, and lysine analog ε-aminocaproic acid significantly inhibited this binding activity, indicating that D. gallinae enolase is a receptor of plasminogen. The present study provided foundation for understanding of the biological functions of DgENO and its application in development of vaccines against D. gallinae.


Assuntos
Antígenos/imunologia , Ácaros/imunologia , Fosfopiruvato Hidratase/química , Vacinas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Anticorpos/isolamento & purificação , Antígenos/química , Antígenos/genética , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Ácaros/enzimologia , Ácaros/genética , Ácaros/crescimento & desenvolvimento , Fosfopiruvato Hidratase/análise , Fosfopiruvato Hidratase/genética , Plasminogênio/metabolismo , Alinhamento de Sequência
4.
Exp Appl Acarol ; 81(2): 201-213, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32444992

RESUMO

The family Phytoseiidae contains many predatory mite species and some are used in biological control programs worldwide. The identification of phytoseiid mites is based on tiny morphological structures and sometimes species diagnosis is not easy especially for non-taxonomists. DNA-based approaches may offer a fast and accurate diagnosis to overcome these difficulties, nevertheless more DNA sequences are needed to determine intra- and inter-specific variations and to provide accurate decision rules based on genetic distances between the taxa considered. In this study, we provide the molecular characterization of seven phytoseiid species based on the internal transcribed spacer (ITS) region. Several populations of these species collected in Turkey were considered. A phylogenetic tree was also constructed. Finally, we record the presence of Neoseiulus reductus (Wainstein) in Turkey.


Assuntos
Ácaros , Comportamento Predatório , Animais , DNA , Ácaros/genética , Filogenia , Turquia
5.
PLoS One ; 15(5): e0233507, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469925

RESUMO

The wheat curl mite, Aceria tosichella Keifer, one of the most destructive arthropod pests of bread wheat worldwide, inflicts significant annual reductions in grain yields. Moreover, A. tosichella is the only vector for several economically important wheat viruses in the Americas, Australia and Europe. To date, mite-resistant wheat genotypes have proven to be one of the most effective methods of controlling the A. tosichella-virus complex. Thus, it is important to elucidate A. tosichella population genetic structure, in order to better predict improved mite and virus management. Two genetically distinct A. tosichella lineages occur as pests of wheat in Australia, Europe, North America, South America and the Middle East. These lineages are known as type 1 and type 2 in Australia and North America and in Europe and South America as MT-8 and MT-1, respectively. Type 1 and type 2 mites in Australia and North America are delineated by internal transcribed spacer 1 region (ITS1) and cytochrome oxidase I region (COI) sequence differences. In North America, two A. tosichella genotypes known as biotypes are recognized by their response to the Cmc3 mite resistance gene in wheat. Aceria tosichella biotype 1 is susceptible to Cmc3 and biotype 2 is virulent to Cmc3. In this study, ITS1 and COI sequence differences in 25 different populations of A. tosichella of known biotype 1 or biotype 2 composition were characterized for ITS1 and COI sequence differences and used to model spatio-temporal dynamics based on biotype prevalence. Results showed that the proportion of biotype 1 and 2 varies both spatially and temporally. Greater ranges of cropland and grassland within 5000m of the sample site, as well as higher mean monthly precipitation during the month prior to sampling appear to reduce the probability of occurrence of biotype 1 and increase the probability of occurrence of biotype 2. The results suggest that spatio-temporal modeling can effectively improve A. tosichella management. Continual integration of additional current and future precipitation and ground cover data into the existing model will further improve the accuracy of predicting the occurrence of A. tosichella in annual wheat crops, allowing producers to make informed decisions about the selection of varieties with different A. tosichella resistance genes.


Assuntos
Ácaros/classificação , Ácaros/genética , Triticum/parasitologia , Animais , Vetores Aracnídeos/patogenicidade , Vetores Aracnídeos/virologia , Resistência à Doença/genética , Grão Comestível/genética , Grão Comestível/parasitologia , Grão Comestível/virologia , Genes de Plantas , Genética Populacional , Genótipo , Meio-Oeste dos Estados Unidos , Ácaros/virologia , Modelos Biológicos , Filogenia , Filogeografia , Doenças das Plantas/parasitologia , Doenças das Plantas/virologia , Análise Espaço-Temporal , Texas , Triticum/genética , Triticum/virologia , Virulência/genética
6.
Proc Natl Acad Sci U S A ; 117(19): 10406-10413, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32341145

RESUMO

Anthropogenic changes create evolutionarily novel environments that present opportunities for emerging diseases, potentially changing the balance between host and pathogen. Honey bees provide essential pollination services, but intensification and globalization of honey bee management has coincided with increased pathogen pressure, primarily due to a parasitic mite/virus complex. Here, we investigated how honey bee individual and group phenotypes are altered by a virus of concern, Israeli acute paralysis virus (IAPV). Using automated and manual behavioral monitoring of IAPV-inoculated individuals, we find evidence for pathogen manipulation of worker behavior by IAPV, and reveal that this effect depends on social context; that is, within versus between colony interactions. Experimental inoculation reduced social contacts between honey bee colony members, suggesting an adaptive host social immune response to diminish transmission. Parallel analyses with double-stranded RNA (dsRNA)-immunostimulated bees revealed these behaviors are part of a generalized social immune defensive response. Conversely, inoculated bees presented to groups of bees from other colonies experienced reduced aggression compared with dsRNA-immunostimulated bees, facilitating entry into susceptible colonies. This reduction was associated with a shift in cuticular hydrocarbons, the chemical signatures used by bees to discriminate colony members from intruders. These responses were specific to IAPV infection, suggestive of pathogen manipulation of the host. Emerging bee pathogens may thus shape host phenotypes to increase transmission, a strategy especially well-suited to the unnaturally high colony densities of modern apiculture. These findings demonstrate how anthropogenic changes could affect arms races between human-managed hosts and their pathogens to potentially affect global food security.


Assuntos
Abelhas/virologia , Dicistroviridae/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Animais , Criação de Abelhas/métodos , Abelhas/genética , Comportamento Animal , Colapso da Colônia/epidemiologia , Vírus de DNA/genética , Vírus de DNA/metabolismo , Dicistroviridae/genética , Dicistroviridae/patogenicidade , Transmissão de Doença Infecciosa/veterinária , Ácaros/genética , Polinização , RNA de Cadeia Dupla , Comportamento Social , Virulência
7.
Exp Appl Acarol ; 80(2): 183-201, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31953632

RESUMO

The grapevine erineum mite strain (GEM) of Colomerus vitis (Pagenstecher) has spread throughout the main viticultural areas worldwide and was recently demonstrated to be a vector of Grapevine pinot gris virus (GPGV) and Grapevine inner necrosis virus (GINV). Its females mainly overwinter under the outer bud scales as winter morphs (deutogynes). Goals of this study were to characterize the morphology of protogynes (spring-summer morphs) and deutogynes (winter morphs), to confirm their genetic similarity, and to establish the seasonal period of the deutogyne occurrence. Buds or leaves from a single vineyard (cv. Luisa), Bari area, Apulia, Italy, infested with GEM were sampled 6 × from December 2015 to January 2017. Sixty-six traits commonly used for taxonomic identification were analysed on females. The length of the tibial setae l' on leg I and the tarsal setae ft' on leg II, as well as the number of smooth dorsal semiannuli differed significantly between protogynes and deutogynes, and were easier to detect than other significantly distinctive traits. ITS1 was investigated in individuals collected from buds and erinea, and the sequences confirmed that these two morphs have identical ITS1 fragments. The 1-year study demonstrated the simultaneous presence of protogynes and deutogynes in July and September 2016, whereas only protogynes were found in April and May 2016, and only deutogynes in December 2015 and January 2017.


Assuntos
Ácaros/anatomia & histologia , Ácaros/genética , Vitis/parasitologia , Animais , Feminino , Itália , Ácaros/virologia , Folhas de Planta/parasitologia
8.
J Parasitol ; 106(1): 82-89, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31999217

RESUMO

Quill mites of the family Syringophilidae (Acariformes: Prostigmata) are permanent ectoparasites that live inside the hollow quills of feathers and use their long chelicerae to pierce the quill wall to feed on living tissue of the quill follicle. Ovenbirds (Parulidae: Seiurus aurocapilla (Linnaeus)) are host to the quill mite Betasyringophiloidus seiuri (Clark), which has been previously reported to infest only 5.1% of this host's tail feathers; however, this species has also been reported to inhabit the wing feathers of ovenbirds, but without any data on prevalence or intensity. We examined all 1,008 flight feathers from 21 dead ovenbirds from Canada for quill mites and calculated infestation parameters per feather location. Nine of the 21 birds were infested with mites (prevalence of 42.9%). Feathers with the highest prevalence were Primaries 1 and 2 and Secondaries 1, 2, and 5. Only 2 of the 9 infested birds had mites in their tail feathers; in each case, only a single feather was infested. Mean intensity was 28.4 mites/feather with a range of 2-135.6, and ∼88% of the adult mites were female. To determine if quill volume and quill wall thickness correlated with mite presence and abundance, we took quill measurements from the flight feathers of 3 additional ovenbirds. There was a strong positive correlation between quill volume and mean mite intensity. Feathers that had quill walls thicker in some areas than the mites' extended chelicerae had lower prevalences than did feathers with walls consistently thinner than the length of the chelicerae. We conclude that B. seiuri is much more likely to be found in wing than in tail feathers and that it has greater reproductive success in quills with both large volumes and thin walls; however, whether foundress mites preferentially choose to colonize these feathers requires more study.


Assuntos
Doenças das Aves/parasitologia , Plumas/parasitologia , Infestações por Ácaros/veterinária , Ácaros/fisiologia , Passeriformes/parasitologia , Alberta/epidemiologia , Animais , Doenças das Aves/epidemiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Masculino , Manitoba/epidemiologia , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/parasitologia , Ácaros/classificação , Ácaros/genética , Ontário/epidemiologia , Prevalência , Razão de Masculinidade
9.
PLoS One ; 15(1): e0225982, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940314

RESUMO

A new monotypic genus Tanopicobia gen. nov. is established for a new species Tanopicobia trachyphoni sp. nov., parasitizing Trachyphonus erythrocephalus Cabanis, 1878 (Piciformes: Lybiidae) from Tanzania. In phylogenetic analyses based on morphological data and constructed using the maximum parsimony approach, this taxon falls within the subfamily Picobiinae Johnston and Kethley, 1973 in the Neopicobia-species-group as closely related to the genus Pipicobia Glowska and Schmidt, 2014. Tanopicobia differs from Pipicobia by the following features in females: genital setae absent; setae ve are situated far and posteromedial to the level of setal bases vi; setae 3a are thick and knobbed. Additionally, a new generic key for subfamily Picobiinae is constructed and general host-parasite ecological and phylogenetic relationships are discussed. Picobiines are present in several lineages of neoavian birds, from basal Galloanseres to terminal Telluraves, which are infested by 70 (89.7% of all) species of these ectoparasites.


Assuntos
Aves/parasitologia , Interações Hospedeiro-Parasita , Ácaros/classificação , Ácaros/fisiologia , Filogenia , Animais , Ácaros/genética
10.
J Med Entomol ; 57(1): 122-130, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31504688

RESUMO

The northern fowl mite (NFM) Ornithonyssus sylviarum Canestrini and Fanzago is a blood-feeding ectoparasite found on many wild bird species and is a pest of poultry in the United States. It is unknown where NFM infestations of poultry originate, which has made it difficult to establish preventative biosecurity or effective control. We used microsatellite markers to evaluate genetic variation within and among NFM populations to determine routes of introduction onto farms and long-term persistence. We compared NFM from flocks of chickens (Gallus gallus) on different farms in California, Washington, and Georgia, and we compared NFM collected over a 5-yr interval. On three farms we collected NFM from chickens and house sparrows (Passer domesticus) nesting on each farm, which we used to assess movement between host species. There was strong genetic structure among mites from different poultry farms and low estimates of migration between farms. There were significant differences between mites on chickens and house sparrows on two farms where sparrows nested near flocks, indicating no exchange of mites. Only one farm showed evidence of NFM movement between chickens and sparrows. There was high genetic similarity between mites collected 5 yr apart on each of two farms, indicating that NFM infestations can persist for long periods. The genetic patterns did not reveal sources of NFM infestations on chicken farms. The data suggest that NFMs are strongly differentiated, which likely reflects periodic population declines with flock turnover and pesticide pressure.


Assuntos
Doenças das Aves/parasitologia , Galinhas , Fluxo Gênico , Infestações por Ácaros/veterinária , Ácaros/genética , Pardais , Animais , California , Georgia , Infestações por Ácaros/parasitologia , Doenças das Aves Domésticas/parasitologia , Washington
11.
Mol Biol Evol ; 37(3): 683-694, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31670799

RESUMO

High-throughput DNA methods hold great promise for phylogenetic analysis of lineages that are difficult to study with conventional molecular and morphological approaches. The mites (Acari), and in particular the highly diverse soil-dwelling lineages, are among the least known branches of the metazoan Tree-of-Life. We extracted numerous minute mites from soils in an area of mixed forest and grassland in southern Iberia. Selected specimens representing the full morphological diversity were shotgun sequenced in bulk, followed by genome assembly of short reads from the mixture, which produced >100 mitochondrial genomes representing diverse acarine lineages. Phylogenetic analyses in combination with taxonomically limited mitogenomes available publicly resulted in plausible trees defining basal relationships of the Acari. Several critical nodes were supported by ancestral-state reconstructions of mitochondrial gene rearrangements. Molecular calibration placed the minimum age for the common ancestor of the superorder Acariformes, which includes most soil-dwelling mites, to the Cambrian-Ordovician (likely within 455-552 Ma), whereas the origin of the superorder Parasitiformes was placed later in the Carboniferous-Permian. Most family-level taxa within the Acariformes were dated to the Jurassic and Triassic. The ancient origin of Acariformes and the early diversification of major extant lineages linked to the soil are consistent with a pioneering role for mites in building the earliest terrestrial ecosystems.


Assuntos
Ácaros/classificação , Mitocôndrias/genética , Solo/parasitologia , Animais , DNA Mitocondrial/genética , Metagenômica , Ácaros/genética , Filogenia , Análise de Sequência de DNA
12.
Ann Dermatol Venereol ; 147(2): 119-122, 2020 Feb.
Artigo em Francês | MEDLINE | ID: mdl-31870576

RESUMO

INTRODUCTION: Mite parasites can be transmitted from animals to humans and cause prurigo. OBSERVATION: We describe a case of mite transmission in a 75-year-old woman referred for pruritus and erythematous maculopapular rash. On clinical examination mites were seen on the patient's skin. The mites were collected and characterized using microscopy. The species was identified as Dermanyssusgallinae, also known as the poultry red mite, an ectoparasite that commonly infests bird nests. The source of the patient's contamination was her henhouse, where mites were found in the wooden beams. Molecular analysis by mitochondrial DNA sequencing was performed on a mite collected from the patient and on a mite collected from the henhouse. This analysis confirmed that both belonged to the D. gallinaes.str species, and that the source of contamination was poultry farming. CONCLUSION: This case describes transmission to a human of the mite D. gallinaes.str via hens, resulting in prurigo, as confirmed by morphological and molecular analysis.


Assuntos
Ácaros/classificação , Prurido/parasitologia , Pele/parasitologia , Idoso , Criação de Animais Domésticos , Animais , DNA Mitocondrial/análise , Feminino , Humanos , Ácaros/genética , Aves Domésticas/parasitologia
13.
Artigo em Chinês | MEDLINE | ID: mdl-33660477

RESUMO

OBJECTIVE: To analyze the sequences of mitochondrial cytochrome C oxidase subunit I gene (COI) and 18S ribosomal RNA gene (18S rRNA), so as to identify the feasible DNA barcodes for 4 species of cheyletid mites and improve the DNA barcoding database for cheyletid mites. METHODS: Cheyletid mite samples were collected from small-scale flour mills in Fuyang, Wuhu and Tongling cities of Anhui Province from May 2018 to July 2019, extracted and morphologically identified. Then, genomic DNA was extracted from a single cheyletid mite, and the COI and 18S rRNA gene sequences were obtained by PCR amplification, cloning and sequencing. The obtained sequences were aligned using the BLAST software. Multiple sequence alignment was done using the software ClustalX version 1.83 using the known gene sequences from cheyletid mites. The genetic distance was calculated using the software MEGA X, and the phylogenetic tree was created using the maximum likelihood method. RESULTS: The DNA barcoding results of Cheyletus malaccensis, C. carnifex and Cheletomorpha lepidopterorum were consistent with the morphological identification, while no sequences pertaining to Eucheyletia reticulate were retrieved in the GenBank database. The proportions of A + T were 69.6% and 55.1% in the COI and 18S rRNA sequences of 4 cheyletid mites species, respectively, and the numbers of base substitutions were 137 and 46, respectively. There were 154 to 321 and 58 to 99 inter-species variation loci in the COI and 18S rRNA gene sequences of 4 cheyletid mites species, respectively, and the intra-species genetic distance was all 0.020 or less in the COI and 18S rRNA gene sequences of 4 cheyletid mites species, with inter-species genetic distance of 0.235 to 0.583 and 0.078 to 0.114, respectively. Phylogenetic analysis based on COI and 18S rRNA genes showed that all four species of cheyletid mites were clustered into a branch with a 100% supportive rate, which was consistent with the morphological identification. CONCLUSIONS: Mitochondrial COI gene is superior to 18S rRNA gene as DNA barcodes for 4 species of cheyletid mites, which is more suitable to be used to investigate the phylogenetic relationship of at genus and species levels.


Assuntos
Código de Barras de DNA Taxonômico , Ácaros , Animais , DNA , Genes de RNAr , Ácaros/genética , Filogenia , RNA Ribossômico 18S/genética
14.
BMC Genomics ; 20(1): 954, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818245

RESUMO

BACKGROUND: Predatory mites (Acari: Phytoseiidae) are the most important beneficial arthropods used in augmentative biological pest control of protected crops around the world. However, the genomes of mites are far less well understood than those of insects and the evolutionary relationships among mite and other chelicerate orders are contested, with the enigmatic origin of mites at one of the centres in discussion of the evolution of Arachnida. RESULTS: We here report the 173 Mb nuclear genome (from 51.75 Gb pairs of Illumina reads) of the predatory mite, Neoseiulus cucumeris, a biocontrol agent against pests such as mites and thrips worldwide. We identified nearly 20.6 Mb (~ 11.93% of this genome) of repetitive sequences and annotated 18,735 protein-coding genes (a typical gene 2888 bp in size); the total length of protein-coding genes was about 50.55 Mb (29.2% of this assembly). About 37% (6981) of the genes are unique to N. cucumeris based on comparison with other arachnid genomes. Our phylogenomic analysis supported the monophyly of Acari, therefore rejecting the biphyletic origin of mites advocated by other studies based on limited gene fragments or few taxa in recent years. Our transcriptomic analyses of different life stages of N. cucumeris provide new insights into genes involved in its development. Putative genes involved in vitellogenesis, regulation of oviposition, sex determination, development of legs, signal perception, detoxification and stress-resistance, and innate immune systems are identified. CONCLUSIONS: Our genomics and developmental transcriptomics analyses of N. cucumeris provide invaluable resources for further research on the development, reproduction, and fitness of this economically important mite in particular and Arachnida in general.


Assuntos
Genoma/genética , Ácaros/classificação , Ácaros/genética , Ácaros e Carrapatos/classificação , Ácaros e Carrapatos/genética , Adaptação Fisiológica/genética , Animais , Agentes de Controle Biológico , Evolução Molecular , Genômica , Imunidade Inata/genética , Estágios do Ciclo de Vida/genética , Ácaros/crescimento & desenvolvimento , Ácaros/fisiologia , Filogenia , Sequências Repetitivas de Ácido Nucleico , Reprodução/genética , Análise de Sequência de DNA , Especificidade da Espécie , Transcriptoma
15.
Sci Rep ; 9(1): 17442, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767919

RESUMO

Some symbiont species are highly host-specific, inhabiting only one or a very few host species, and typically have limited dispersal abilities. When they do occur on multiple host species, populations of such symbionts are expected to become genetically structured across these different host species, and this may eventually lead to new symbiont species over evolutionary timescales. However, a low number of dispersal events of symbionts between host species across time might be enough to prevent population structure and species divergence. Overall, processes of evolutionary divergence and the species status of most putative multi-host symbiont systems are yet to be investigated. Here, we used DNA metabarcoding data of 6,023 feather mites (a total of 2,225 OTU representative sequences) from 147 infracommunities (i.e., the assemblage consisting of all mites of different species collected from the same bird host individual) to investigate patterns of population genetic structure and species status of three different putative multi-host feather mite species Proctophyllodes macedo Vitzthum, 1922, Proctophyllodes motacillae Gaud, 1953, and Trouessartia jedliczkai (Zimmerman, 1894), each of which inhabits a variable number of different closely related wagtail host species (genus Motacilla). We show that mite populations from different host species represent a single species. This pattern was found in all the mite species, suggesting that each of these species is a multi-host species in which dispersal of mites among host species prevents species divergence. Also, we found evidence of limited evolutionary divergence manifested by a low but significant level of population genetic structure among symbiont populations inhabiting different host species. Our study agrees with previous studies showing a higher than expected colonization opportunities in host-specific symbionts. Indeed, our results support that these dispersal events would allow the persistence of multi-host species even in symbionts with limited dispersal capabilities, though additional factors such as the geographical structure of some bird populations may also play a role.


Assuntos
Especificidade de Hospedeiro , Ácaros/classificação , Passeriformes , Simbiose , Distribuição Animal , Animais , Sequência de Bases , Biodiversidade , Sequência Conservada , Código de Barras de DNA Taxonômico , DNA Mitocondrial/genética , Especiação Genética , Genética Populacional , Haplótipos/genética , Ácaros/genética , Passeriformes/classificação , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Espanha , Especificidade da Espécie
16.
Zootaxa ; 4560(2): zootaxa.4560.2.11, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31716588

RESUMO

Sperchon fuxiensis Zhang, 2017 was published as a new species based on females alone. Two males of Sperchon were found in the same locality during our recent collection. The males resemble S. fuxiensis female in the integument pattern, excretory pore and the palps shape, but the chitinous plates of both dorsum and venter differ greatly. The males were paired with the female of S. fuxiensis using DNA barcoding, revealing unusual sexual dimorphism in the species. Descriptions and illustrations of the male of S. fuxiensis are given in the present study. Species identification based on the full-length DNA barcoding (658bp) of COI in water mites is also discussed.


Assuntos
Ácaros , Animais , DNA , Código de Barras de DNA Taxonômico , Feminino , Masculino , Ácaros/genética , Caracteres Sexuais , Água
17.
Parasitol Res ; 118(12): 3223-3235, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31691855

RESUMO

Demodex are among the tiniest organisms in Acari and are important mammalian parasites. However, differences in pathogenicity between two human parasites, Demodex folliculorum and Demodex brevis, remain unknown. Related genetic studies are limited by RNA extraction difficulties and molecular data deficiencies. In this study, RNA extraction, de novo sequencing, functional annotation, and differential gene expression analyses were performed to compare D. folliculorum and D. brevis. This yielded 67.09 and 65.10 million clean reads, respectively, with similar annotations. Bioinformatics analyses and manual alignments identified 237 coding sequences comprising 48 genes from 29 families, including five important functional classes. Of these, 30 genes from 20 families related to metabolism, motion, detoxification and stress response, and allergic reaction were differentially expressed between the two species. Cathepsin type 1, serine protease inhibitor, arginine kinase, triosephosphate isomerase, muscle-specific protein 20-2, myosin alkaline light chain, troponin C, tropomyosin, and heat shock protein 90 were highly expressed in D. folliculorum, whereas cathepsin type 2, aspartic protease, serine protease, myosin heavy chain type 2, and alpha tubulin type 1C were highly expressed in D. brevis. Verified coding sequences were nearly consistent with unigene clusters. Further, absolute quantification results demonstrated that differentially expressed genes followed the predicted expression trend. Therefore, the first RNA sequencing and functional annotation analysis of two Demodex species was successful. Differential expression of important functional genes is likely implicated in pathogenicity disparities between these two species. Our study provides molecular data and technical support for further studies on human Demodex pathogenicity and functional genes.


Assuntos
Ácaros/genética , Animais , Proteínas de Artrópodes/genética , Perfilação da Expressão Gênica , Humanos , Ácaros/classificação , Ácaros/patogenicidade , Especificidade da Espécie , Transcriptoma , Virulência/genética
18.
Commun Biol ; 2: 387, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31667361

RESUMO

The early evolution of ecosystems in Palaeozoic soils remains poorly understood because the fossil record is sparse, despite the preservation of soil microarthropods already from the Early Devonian (~410 Mya). The soil food web plays a key role in the functioning of ecosystems and its organisms currently express traits that have evolved over 400 my. Here, we conducted a phylogenetic trait analysis of a major soil animal group (Oribatida) to reveal the deep time story of the soil food web. We conclude that this group, central to the trophic structure of the soil food web, diversified in the early Paleozoic and resulted in functionally complex food webs by the late Devonian. The evolution of body size, form, and an astonishing trophic diversity demonstrates that the soil food web was as structured as current food webs already in the Devonian, facilitating the establishment of higher plants in the late Paleozoic.


Assuntos
Ecossistema , Cadeia Alimentar , Ácaros/classificação , Solo , Animais , Tamanho Corporal , Evolução Molecular , Fósseis , História Antiga , Ácaros/anatomia & histologia , Ácaros/genética , Filogenia
19.
Exp Appl Acarol ; 79(3-4): 309-321, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31673886

RESUMO

Macrocheles muscaedomesticae is a cosmopolitan macrochelid mite whose populations have likely diverged considering the many locations they inhabit, but most of the work published on this mite species has been on the basis of their association with the house fly, Musca domestica. Here, we studied several aspects of the biology of M. muscaedomesticae associated with drosophilid flies collected in Alberta, Canada. We assessed the degree of divergence of our populations from others, compared their life history to other published populations and experimentally tested whether M. muscaedomesticae feeds on Drosophila hydei hosts by comparing the body mass of mites that attached to hosts to those that did not. There was no strong phylogenetic differentiation among any of the M. muscaedomesticae specimens, suggesting multiple recent introductions of this species to Canada. Compared to other populations, our mites exhibited lower fecundity, which may have been a result of the temperature or nematode-only diet in which they were maintained. Finally, mites that attached to hosts for 4 h weighed significantly more than those that did not. Without direct evidence for host tissue transfer to the mites, it is difficult to determine whether the mites are indeed feeding on their hosts while attached. However, the existing evidence for the costs fly hosts endure at the expense of these mites makes this relationship antagonistic.


Assuntos
Drosophila/parasitologia , Genética Populacional , Ácaros/genética , Animais , Canadá , Fertilidade , Ácaros/fisiologia , Filogenia
20.
Mol Ecol ; 28(24): 5347-5359, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31674085

RESUMO

Mites (Arachnida: Acariformes, Parasitiformes) are the most abundant and species-rich group of arthropods in soil, but are also diverse in freshwater habitats, on plants, and as symbionts of larger animals. However, assessment of their diversity has been impeded by their small size and often cryptic morphology. As a consequence, published estimates of their species richness span more than two orders of magnitude (0.4-114 million). In this study we employ DNA barcoding and the Barcode Index Number (BIN) system to investigate mite diversity at over 1,800 sites across Canada, primarily from soil and litter habitats with smaller contributions from freshwater, plants, and animal hosts. Barcodes from 73,394 specimens revealed 7,077 BINs with representatives from all four orders (Ixodida, Mesostigmata, Sarcoptiformes, Trombidiformes) and 60% (186) of the known families. The BIN total is 2.4 times the number of species previously recorded from Canada (2,999), reflecting the unexpectedly high richness of several families. Richness projections suggest that more than 28,000 BINs occur at the sampled locations, indicating that the Canadian mite fauna almost certainly includes more than 30,000 species-a total similar to that for the most diverse insect order in Canada, Diptera. This unexpected diversity was partitioned into highly dissimilar, spatially-structured assemblages that likely reflect dispersal limitation and environmental heterogeneity. Further sampling of a greater diversity of habitats will refine understanding of mite diversity in Canada, but similar analyses in other geographic regions will be essential to ascertain their diversity at a global scale.


Assuntos
Código de Barras de DNA Taxonômico , Variação Genética/genética , Ácaros/genética , Animais , Aracnídeos/classificação , Aracnídeos/genética , Canadá , DNA/genética , Ecossistema , Ácaros/classificação
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