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1.
Invertebr Syst ; 382024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38744525

RESUMEN

The rhinebothriidean tapeworm family Escherbothriidae has recently been expanded to include the genus Ivanovcestus , species of which parasitise arhynchobatid skates. Similarities in morphology and host associations between Ivanovcestus and Semiorbiseptum - a genus yet to be assigned to one of the families in the order Rhinebothriidea - led us to explore the possibility that Semiorbiseptum might also belong in the Escherbothriidae. Morphological similarities with Scalithrium ivanovae , Scalithrium kirchneri and Rhinebothrium scobinae , all of which also parasitise arhynchobatid skates, raised questions regarding the generic placements of these species. In addition, new collections from the skate Sympterygia brevicaudata revealed two new species that morphologically resemble species of Ivanovcestus . A combination of morphological and molecular data were used to assess the generic placement of the newly discovered species and refine our understanding of the membership of the family Escherbothriidae. Sequence data for the D1-D3 region of the 28S rDNA gene were generated de novo for 14 specimens of 7 rhinebothriidean species and combined with comparable published data to represent all 6 families in the Rhinebothriidea in the analysis. The phylogenetic tree resulting from maximum likelihood analysis strongly supports the inclusion of the genus Semiorbiseptum in the family Escherbothriidae. Our work also suggests that the skate-hosted species previously assigned to Scalithrium and Rhinebothrium are also members of Semiorbiseptum and that Ivanovcestus is a junior synonym of Semiorbiseptum . Six species are transferred to Semiorbiseptum , bringing the total number of species in the genus to ten. The diagnosis of Semiorbiseptum is amended to accommodate the additional species. A second species in the previously monotypic type genus of the family, Escherbothrium , is described. The diagnosis of the Escherbothriidae is amended to include the new and transferred species. This study underscores the importance of integrating morphological and molecular data in bringing resolution to cestode systematics. We believe our findings provide a robust foundation for future research into the evolutionary history and host associations of cestodes within the order Rhinebothriidea and beyond. These also highlight the importance of expanding our understanding of skate-hosted cestodes. ZooBank: urn:lsid:zoobank.org:pub:8052AFCA-5FBD-4430-95F4-0E5E368DEA3D.


Asunto(s)
Cestodos , Filogenia , Rajidae , Cestodos/genética , Cestodos/clasificación , Animales , Rajidae/parasitología , Especificidad de la Especie , ARN Ribosómico 28S/genética
2.
Syst Parasitol ; 101(3): 41, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740609

RESUMEN

Dicrocoeliid trematodes were detected from Iwasaki's snail-eating snake Pareas iwasakii in Iriomote Island, Okinawa Prefecture, Japan, and described as a new species Paradistomum dextra n. sp. in the present study. This new species can be distinguished from the type series of the other members of the genus based on size of eggs and morphological characteristics of body, oral and ventral suckers, and reproductive organs. However, the new species was hard to distinguish from Paradistomum megareceptaculum infecting snakes in Japan, including Iriomote Island where is the type locality of the new species, because it is closely similar to some part of the broad range of morphological variations in P. megareceptaculum. On the other hand, a partial sequence of 28S ribosomal DNA clearly distinguished these two species. Moreover, the new species' host snake Pareas iwasakii is reported to exclusively feed on land snails while host snakes of P. megareceptaculum feed on small vertebrates, indicating that the new species is also ecologically different from P. megareceptaculum. We also redescribed P. megareceptaculum based on adults sampled in this study and past studies to record the morphological variations of this species.


Asunto(s)
Especificidad de la Especie , Trematodos , Animales , Japón , Trematodos/clasificación , Trematodos/anatomía & histología , Trematodos/genética , Caracoles/parasitología , ARN Ribosómico 28S/genética , Serpientes/parasitología , Filogenia
3.
J Helminthol ; 98: e37, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38706044

RESUMEN

The genus Ancyrocephalus sensu lato is a large assemblage of species of dactylogyrid monopisthocotyleans without clear taxonomic boundaries. Despite an urgent need for revision, only three representatives of this taxon have been molecularly characterised so far. We found specimens of Ancyrocephalus curtus, a previously non-genotyped species, in gills of Perccottus glenii caught in the River Syumnyur, Amur Basin, Russia. The aim of this study was to assess the phylogenetic position of this parasite using partial sequences of 28S rRNA gene. In the phylogenetic tree, A. curtus appeared as a sister taxon to the dactylogyrine genus Gobioecetes. The new molecular evidence supports the hypothesis about the non-monophyletic status of Ancyrocephalus sensu lato.


Asunto(s)
Enfermedades de los Peces , Branquias , Perciformes , Filogenia , ARN Ribosómico 28S , Animales , Enfermedades de los Peces/parasitología , Branquias/parasitología , Perciformes/parasitología , ARN Ribosómico 28S/genética , Federación de Rusia , Ríos/parasitología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/veterinaria , Platelmintos/clasificación , Platelmintos/genética , Platelmintos/aislamiento & purificación , ADN de Helmintos/genética , Trematodos/genética , Trematodos/clasificación , Trematodos/aislamiento & purificación , ADN Ribosómico/genética , Análisis de Secuencia de ADN
4.
J Parasitol ; 110(3): 186-194, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38700436

RESUMEN

Leech specimens of the genus Pontobdella (Hirudinida: Piscicolidae) were found off the coast of the state of Oaxaca (Pacific) as well as in Veracruz and Tabasco (Gulf of Mexico), Mexico. Based on the specimens collected in Oaxaca, a redescription of Pontobdella californiana is provided, with emphasis on the differences in the reproductive organs with the original description of the species. In addition, leech cocoons assigned to P. californiana were found attached to items hauled by gillnets and studied using scanning electron microscopy and molecular approaches. Samples of Pontobdella macrothela were found in both Pacific and Atlantic oceans, representing new geographic records. The phylogenetic position of P. californiana is investigated for the first time, and with the addition of Mexican samples of both species, the phylogenetic relationships within Pontobdella are reinvestigated. Parsimony and maximum-likelihood phylogenetic analysis were based on mitochondrial (cytochrome oxidase subunit I [COI] and 12S rRNA) and nuclear (18S rRNA and 28S rRNA) DNA sequences. Based on our results, we confirm the monophyly of Pontobdella and the pantropical distribution of P. macrothela with a new record in the Tropical Eastern Pacific.


Asunto(s)
Sanguijuelas , Microscopía Electrónica de Rastreo , Filogenia , Animales , Sanguijuelas/clasificación , Sanguijuelas/genética , Sanguijuelas/anatomía & histología , México , Microscopía Electrónica de Rastreo/veterinaria , Océano Pacífico , Océano Atlántico , ADN Ribosómico/química , ARN Ribosómico 28S/genética , Enfermedades de los Peces/parasitología , Golfo de México/epidemiología , Complejo IV de Transporte de Electrones/genética , Infestaciones Ectoparasitarias/parasitología , Infestaciones Ectoparasitarias/veterinaria , ARN Ribosómico 18S/genética , Datos de Secuencia Molecular , Alineación de Secuencia/veterinaria , Funciones de Verosimilitud , Peces/parasitología
5.
Syst Parasitol ; 101(3): 35, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700732

RESUMEN

Two new species of Urocleidoides are described from the gills of Pseudanos trimaculatus (Characiformes: Anostomidae) from the coastal drainages of the Eastern Amazon, Brazil. Urocleidoides itabocaensis n. sp. is characterized by having a sclerotized, tubular, sigmoid male copulatory organ (MCO), a circular sclerotized tandem brim associated with the base of the MCO; an accessory piece articulated with the MCO, a V-shaped, divided into two subunits, distal subunit spoon-shaped; and a vaginal pore dextroventral with opening marginal. Urocleidoides omphalocleithrum n. sp. is characterized by presenting a C-shaped or sigmoid MCO; an accessory piece articulated with the MCO, L-shaped, divided into two subunits, distal subunit gutter-shaped; a vaginal pore dextroventral with opening marginal; and a ventral bar broadly V-shaped, with anteromedial projection. Molecular phylogenetic analysis based on partial 28S rDNA and COI mtDNA genes indicate that U. itabocaensis n. sp. and U. omphalocleithrum n. sp. are closely related and appear as a sister group to other Urocleidoides species (U. paradoxus, U. digitabulum and U. sinus) parasitizing anostomid fishes. This study represents the first record of monogenoids from the gills of P. trimaculatus for the Eastern Amazon.


Asunto(s)
Characiformes , Filogenia , Especificidad de la Especie , Animales , Brasil , Characiformes/parasitología , Branquias/parasitología , Trematodos/clasificación , Trematodos/genética , Trematodos/anatomía & histología , ARN Ribosómico 28S/genética , Masculino
6.
J Helminthol ; 98: e38, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721629

RESUMEN

The deepest recorded depth for trematodes currently stands at approximately 6200 m. This depth record was achieved solely through sequence datasets of Lepidapedon sp. obtained from a gastropod. Given that trematodes of this genus typically use fish as definitive hosts, the origin of the trematode sequence was thought to be larval stages. However, the specific species remained unclear owing to the absence of reported adult-stage sequences. In the present study, we definitively identified the deepest trematode as Lepidapedon oregonense by comparing 28S ribosomal DNA sequences from adult worms from the macrourid fish Coelorinchus gilberti with data from the gastropod in the previous study.


Asunto(s)
ADN de Helmintos , ADN Ribosómico , Filogenia , ARN Ribosómico 28S , Trematodos , Animales , Trematodos/clasificación , Trematodos/genética , Trematodos/aislamiento & purificación , ARN Ribosómico 28S/genética , ADN de Helmintos/genética , ADN Ribosómico/genética , Gastrópodos/parasitología , Análisis de Secuencia de ADN , Peces/parasitología , Enfermedades de los Peces/parasitología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/veterinaria
7.
J Helminthol ; 98: e39, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38726571

RESUMEN

During nematode surveys of natural vegetation in forests of La Cima de Copey de Dota, San José, San José province, Costa Rica, a Xenocriconemella species closely resembling X. macrodora and related species was found. Integrative taxonomical approaches demonstrated that it is a new species described herein as X. costaricense sp. nov. The new species is parthenogenetic (only females have been detected) and characterised by a short body (276-404 µm); lip region with two annuli, not offset, not separated from body contour; first lip annulus partially covering the second lip annulus. Stylet thin, very long (113-133 µm) and flexible, occupying 30.5-47.8% of body length. Excretory pore located from one or two annuli anterior to one or two annuli posterior to level of stylet knobs, at 42 (37-45) µm from anterior end. Female genital tract monodelphic, prodelphic, outstretched, and occupying 35-45% of body length, with vagina slightly ventrally curved (14-18 µm long). Anus located 6-11 annuli from the tail terminus. Tail conoid and bluntly rounded terminus, the last 2-3 annuli oriented dorsally. Results of molecular characterisation and phylogenetic analyses of D2-D3 expansion segments of 28S rRNA, ITS, and partial 18S rRNA, as well as cytochrome oxidase c subunit 1 gene sequences further characterised the new species and clearly separated it from X. macrodora and other related species (X. iberica, X. paraiberica, and X. pradense).


Asunto(s)
Filogenia , Animales , Costa Rica , Femenino , Masculino , Nematodos/clasificación , Nematodos/anatomía & histología , Nematodos/genética , ADN Ribosómico/genética , ARN Ribosómico 28S/genética , ADN de Helmintos/genética , Bosques , Análisis de Secuencia de ADN
8.
Parasite ; 31: 26, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38775717

RESUMEN

Several studies have shown that the euryxenic trematode Derogenes varicus (Müller, 1784) represents a species complex. Four lineages have been designated (DV1-4) with the DV1 clade corresponding to D. varicus sensu stricto. Herein, we investigate newly collected specimens of D. varicus sensu lato from Scandinavian and Arctic waters using integrative taxonomy. The trematodes were collected from Melanogrammus aeglefinus, Eutrigla gurnardus, Trachinus draco, and Merluccius merluccius off the Atlantic coast of Sweden and from Hippoglossoides platessoides from Arctic Svalbard. 28S sequences of derogenids from Sweden were identical to D. varicus sensu stricto, confirming its euryxeny. The 28S sequences of Derogenes sp. from H. platessoides were identical to Derogenes DV2 and differed from D. varicus sensu stricto by 3% and from Derogenes DV3 by 2%. The 28S sequence divergences of Derogenes sp. from H. platessoides with D. ruber and D. lacustris were 3 and 10%, respectively. ITS2 and cox1 divergences between Derogenes sp. from H. platessoides and other Derogenes species/lineages were at levels of interspecific differences. The species from H. platessoides is described here as D. abba n. sp. We also examined the type material of Progonus muelleri (Levinsen, 1881), the type and only species of the genus Progonus, with redescription and designations of paralectotypes. Based on specimens from Theodor Odhner's collections at the Swedish Museum of Natural History, SMNH, Stockholm, we provide novel morphological and anatomical data for D. varicus sensu lato species complex. Lastly, we investigated Arthur Looss's "lost collection" of Trematodes at the SMNH and characterised a putative species Derogenes sp. "limula".


Title: Démêler le complexe d'espèces Derogenes varicus dans les eaux scandinaves et arctiques : description de Derogenes abba n. sp. (Trematoda, Derogenidae) parasite d'Hippoglossoides platessoides et nouveaux signalements d'hôtes pour D. varicus (Müller, 1784) sensu stricto. Abstract: Plusieurs études ont montré que le trématode euryxene Derogenes varicus (Müller, 1784) représente un complexe d'espèces. Quatre lignées ont été désignées (DV1­4), le clade DV1 correspondant à D. varicus sensu stricto. Ici, nous étudions des spécimens nouvellement collectés de D. varicus sensu lato dans les eaux scandinaves et arctiques en utilisant la taxonomie intégrative. Les trématodes ont été collectés de Melanogrammus aeglefinus, Eutrigla gurnardus, Trachinus draco et Merluccius merluccius au large de la côte atlantique de la Suède et d'Hippoglossoides platessoides du Svalbard arctique. Les séquences 28S des Derogenidae de Suède étaient identiques à D. varicus sensu stricto, confirmant son euryxénie. Les séquences 28S de Derogenes sp. de H. platessoides étaient identiques à Derogenes DV2 et différaient de D. varicus sensu stricto par 3% et de Derogenes DV3 par 2%. Les divergences des séquence 28S de Derogenes sp. de H. platessoides avec D. ruber et D. lacustris étaient respectivement de 3 et 10%. Les divergences ITS2 et cox1 entre Derogenes sp. de H. platessoides et d'autres espèces/lignées de Derogenes se situaient à des niveaux de différences interspécifiques. L'espèce de H. platessoides est décrite ici comme Derogenes abba n. sp. Nous avons également examiné le matériel type de Progonus muelleri (Levinsen, 1881), type et seule espèce du genre Progonus, avec une redescription et des désignations de paralectotypes. Sur la base de spécimens des collections de Theodor Odhner au Musée suédois d'histoire naturelle (SMNH), Stockholm, nous fournissons de nouvelles données morphologiques et anatomiques sur le complexe d'espèces de D. varicus sensu lato. Enfin, nous avons étudié la « collection perdue ¼ de Trématodes d'Arthur Looss au SMNH et caractérisé une espèce putative, Derogenes sp. « limula ¼.


Asunto(s)
Filogenia , Trematodos , Infecciones por Trematodos , Animales , Trematodos/clasificación , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación , Trematodos/genética , Regiones Árticas , Infecciones por Trematodos/veterinaria , Infecciones por Trematodos/parasitología , Suecia , Enfermedades de los Peces/parasitología , ARN Ribosómico 28S/genética , Gadiformes/parasitología , Svalbard , ADN de Helmintos
9.
Chem Commun (Camb) ; 60(33): 4479-4482, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38564258

RESUMEN

We found that the N6 methyl group of N6-methyladenine is able to hinder the methylation of N6-methyladenine at the N1 position by DMS. Based on this, we have devised a novel method for detecting N6-methyladenine, which was successfully applied to identify specific m6A loci in 28S rRNA.


Asunto(s)
Metilación , ARN Ribosómico 28S
10.
BMC Genomics ; 25(1): 345, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580917

RESUMEN

BACKGROUND: High-mobility group B1 (HMGB1) is both a DNA binding nuclear factor modulating transcription and a crucial cytokine that mediates the response to both infectious and noninfectious inflammation such as autoimmunity, cancer, trauma, and ischemia reperfusion injury. HMGB1 has been proposed to control ribosome biogenesis, similar as the other members of a class of HMGB proteins. RESULTS: Here, we report that HMGB1 selectively promotes transcription of genes involved in the regulation of transcription, osteoclast differentiation and apoptotic process. Improved RNA immunoprecipitation by UV cross-linking and deep sequencing (iRIP-seq) experiment revealed that HMGB1 selectively bound to mRNAs functioning not only in signal transduction and gene expression, but also in axon guidance, focal adhesion, and extracellular matrix organization. Importantly, HMGB1-bound reads were strongly enriched in specific structured RNAs, including the domain II of 28S rRNA, H/ACA box snoRNAs including snoRNA63 and scaRNAs. RTL-P experiment showed that overexpression of HMGB1 led to a decreased methylation modification of 28S rRNA at position Am2388, Cm2409, and Gm2411. We further showed that HMGB1 overexpression increased ribosome RNA expression levels and enhanced protein synthesis. CONCLUSION: Taken together, our results support a model in which HMGB1 binds to multiple RNA species in human cancer cells, which could at least partially contribute to HMGB1-modulated rRNA modification, protein synthesis function of ribosomes, and differential gene expression including rRNA genes. These findings provide additional mechanistic clues to HMGB1 functions in cancers and cell differentiation.


Asunto(s)
Proteína HMGB1 , Metilación de ARN , Humanos , Células HeLa , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Metilación , ARN Ribosómico 28S/metabolismo , ARN Nucleolar Pequeño/química , ARN Nucleolar Pequeño/genética , ARN Nucleolar Pequeño/metabolismo , Metilación de ARN/genética
11.
J Invertebr Pathol ; 204: 108112, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38631556

RESUMEN

Trematodes of the genus Leucochloridium exhibit an unusual transmission strategy among mollusks (intermediate host). The fully developed sporocyst, housing encysted metacercariae, displays vivid coloration and rhythmic activity in the snail's tentacle, mimicking insect larvae. These strategies attract insectivorous birds, their final hosts, thereby increasing the chances of completing their life cycle. In South America, the reports of adults and larval stages of Leucochloridium are scarce. Brown-banded broodsac of Leucochloridium sp. were obtained from Omalonyx unguis collected in a shallow lake from Corrientes Province, Argentina. Here, we morphologically characterized the larval stages (broodsac and metacercaria), identified the parasite through DNA sequences from nuclear 28S-rRNA (28S) and the mitochondrial cytochrome c oxidase I (COI) genes, and explored its evolutionary affinities with the Leucochloridium species available in GenBank. The present broodsac displays brown bands, with a yellowish background in the first two-thirds and yellowish-white in the last third. Based on morphological comparisons, the broodsac and metacercaria described in this study could not be conclusively categorized under any known South American species of Leucochloridium. In relation to the phylogenetic reconstructions, Leucochloridium sp. consistently clustered with L. perturbatum, and species delimitation analyses resulted in recognized Leucochloridium sp. from Argentina as a distinct species. The DNA sequences obtained in this study constitute the first genetic data generated for sporocyst broodsacs in South America. Future studies, incorporating morphology, genetic, and biological data, will be essential for both species identification and the elucidation of leucochloridiid diversity in the region.


Asunto(s)
Trematodos , Animales , Argentina , Trematodos/genética , Trematodos/fisiología , Trematodos/anatomía & histología , Metacercarias , Filogenia , Gastrópodos/parasitología , ARN Ribosómico 28S/genética , ARN Ribosómico 28S/análisis
12.
J Helminthol ; 98: e36, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38659305

RESUMEN

New morphological and molecular data were generated for trematodes recovered from the intestines of the fish Pseudaspius hakonensis from two locations in the south of the Russian Far East. Morphologically, these trematodes are identical to Pseudozoogonoides ugui (Microphalloidea: Zoogonidae) from Japan. According to results of phylogenetic analysis based on 28S rDNA sequence data, P. ugui was closely related to Zoogonoides viviparus, and P. subaequiporus appears as a sister taxon to these two species. Genetic distance values, calculated based on both 28S rDNA and ITS2 rDNA, between P. ugui and Z. viviparus represents an interspecific differentiation level. Our results have an ambiguous explanation, indicating that the implication of the presence of one or two compact vitellarial aggregations for the differentiation of Zoogonoides and Pseudozoogonoides should be reconsidered or that our results open up the question of the taxonomical status of trematodes previously denoted as Z. viviparus and P. subaequiporus.


Asunto(s)
ADN de Helmintos , ADN Ribosómico , Enfermedades de los Peces , Filogenia , ARN Ribosómico 28S , Trematodos , Infecciones por Trematodos , Animales , Trematodos/genética , Trematodos/clasificación , Trematodos/anatomía & histología , ARN Ribosómico 28S/genética , Enfermedades de los Peces/parasitología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/veterinaria , ADN de Helmintos/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Federación de Rusia , Análisis de Secuencia de ADN , Intestinos/parasitología
13.
Pestic Biochem Physiol ; 200: 105838, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38582600

RESUMEN

Diaspididae are one of the most serious small herbivorous insects with piercing-sucking mouth parts and are major economic pests as they attack and destroy perennial ornamentals and food crops. Chemical control is the primary management approach for armored scale infestation. However, chemical insecticides do not possess selectivity in action and not always effective enough for the control of armored scale insects. Our previous work showed that green oligonucleotide insecticides (olinscides) are highly effective against armored and soft scale insects. Moreover, olinscides possess affordability, selectivity in action, fast biodegradability, and a low carbon footprint. Insect pest populations undergo microevolution and olinscides should take into account the problem of insecticide resistance. Using sequencing results, it was found that in the mixed populations of insect pests Dynaspidiotus britannicus Newstead and Aonidia lauri Bouche, predominates the population of A. lauri. Individuals of A. lauri comprised for 80% of individuals with the sequence 3'-ATC-GTT-GGC-AT-5' in the 28S rRNA site, and 20% of the population comprised D. britannicus individuals with the sequence 3'-ATC-GTC-GGT-AT-5'. We created olinscides Diasp80-11 (5'-ATG-CCA-ACG-AT-3') and Diasp20-11 (5'-ATA-CCG-ACG-AT-3') with perfect complementarity to each of the sequences. Mortality of insects on the 14th day comprised 98.19 ± 3.12% in Diasp80-11 group, 64.66 ± 0.67% in Diasp20-11 group (p < 0.05), and 3.77 ± 0.94% in the control group. Results indicate that for maximum insecticidal effect it is necessary to use an oligonucleotide insecticide that corresponds to the dominant species. Mortality in Diasp80-11 group was accompanied with significant decrease in target 28S rRNA concentration and was 8.44 ± 0.14 and 1.72 ± 0.36 times lower in comparison with control (p < 0.05) on the 10th and 14th days, respectively. We decided to make single nucleotide substitutions in Diasp20-11 olinscide to understand which nucleotide will play the most important role in insecticidal effect. We created three sequences with single nucleotide transversion substitutions at the 5'-end - Diasp20(5')-11 (A to T), 3'-end - Diasp20(3')-11 (T to A), and in the middle of the sequence - Diasp20(6)-11 (6th nitrogenous base of the sequence; G to C), respectively. As a result, mortality of mixed population of the field experiment decreased and comprised 53.89 ± 7.25% in Diasp20(5')-11 group, 40.68 ± 4.33% in Diasp20(6)-11 group, 35.74 ± 5.51% in Diasp20(3')-11 group, and 3.77 ± 0.94% in the control group on the 14th day. Thus, complementarity of the 3'-end nucleotide to target 28S rRNA was the most important for pronounced insecticidal effect (significance of complementarity of nucleotides for insecticidal effect: 5' nt < 6 nt < 3' nt). As was found in our previous research works, the most important rule to obtain maximum insecticidal effect is complete complementarity to the target rRNA sequence and maximum coverage of target sequence in insect pest populations. However, in this article we also show that the complementarity of 3'-end is a second important factor for insecticidal potential of olinscides. Also in this article we propose 2-step DNA containment mechanism of action of olinscides, recruiting RNase H. The data obtained indicate the selectivity of olinscides and at the same time provide a simple and flexible platform for the creation of effective plant protection products, based on antisense DNA oligonucleotides.


Asunto(s)
Hemípteros , Insecticidas , Humanos , Animales , Insecticidas/farmacología , Oligonucleótidos , Nucleótidos , ARN Ribosómico 28S , Insectos/genética , Control de Insectos/métodos
14.
J Helminthol ; 98: e35, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651383

RESUMEN

As part of a parasitological survey, several specimens of two new monopisthocotylean species, Neotetraonchus celsomanueli sp. nov. and N.peruvianus sp. nov. (Dactylogyridea, Dactylogyridae), were collected from the gill filaments of the Peruvian sea catfish Galeichthys peruvianus (Siluriformes, Ariidae) off Puerto Pizarro, Tumbes region, Peru. Neotetraonchus celsomanueli sp. nov. is characterised by an MCO with a T-shaped distal end and an accessory piece that is ribbed and expanded proximally with a worm-shaped termination. Neotetraonchus peruvianus sp. nov. is typified by its MCO, which has a sledgehammer-shaped distal end and an accessory piece with a claw-shaped distal end. Additionally, N.peruvianus sp. nov. is characterised by its jellyfish-shaped onchium. A partial 28S rDNA sequence was obtained from N.celsomanueli sp. nov., and a phylogenetic analysis was conducted. This analysis revealed the phylogenetic position of Neotetraonchus celsomanueli sp. nov. within a clade comprising monopisthocotylean parasites of diadromous and marine ariid catfishes, including Hamatopeduncularia spp., Chauhanellus spp., Thysanotohaptor Kritsky, Shameem, Kumari & Krishnaveni, , and Neocalceostomoides spinivaginalis Lim, 1995. This finding brings the number of known Neotetraonchus species to seven and represents the first described Neotetraonchus species infecting marine catfishes from Peru.


Asunto(s)
Bagres , Enfermedades de los Peces , Branquias , Filogenia , Animales , Bagres/parasitología , Perú , Enfermedades de los Peces/parasitología , Branquias/parasitología , Infecciones por Trematodos/veterinaria , Infecciones por Trematodos/parasitología , ADN Ribosómico/genética , Trematodos/clasificación , Trematodos/genética , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación , ADN de Helmintos/genética , ARN Ribosómico 28S/genética , Platelmintos/clasificación , Platelmintos/genética , Platelmintos/anatomía & histología , Platelmintos/aislamiento & purificación , Análisis de Secuencia de ADN
15.
J Parasitol ; 110(2): 114-126, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38503317

RESUMEN

An inventory of parasites infecting the jaguar (Panthera onca) across its distribution range is relevant for the conservation of this threatened big cat. In this study, we report the occurrence of helminths in a jaguar from Mexico using morphological techniques (cleared and stained mounts and scanning electron microscopy) and partial sequences of the 28S ribosomal RNA (28S rRNA) gene and the cytochrome c oxidase 1 mitochondrial (COI) gene. We also provide an updated list of helminth species reported in jaguars in the Americas. Three helminth taxa are identified in the jaguar examined from Mexico: Toxocara cati, Physaloptera sp., and Taenia sp. The new 28S rRNA sequences of To. cati, Physaloptera sp., and Taenia sp. and the COI sequence of Taenia sp. corroborate the identity of the helminths isolated from this host. One hundred and twenty-nine records of helminths parasitizing jaguars from 49 studies up to May 2023 were identified in the Americas. In most of these studies (73.6%), helminths were identified using coproparasitological techniques. Sixteen helminths (7 nematodes, 5 cestodes, 3 acanthocephalans, and 1 trematode) were identified at the species level in free-ranging and captive jaguars. The study demonstrates the value of an integrative taxonomy approach to increase the accuracy of parasite identification in wildlife, especially when helminth specimens are scarce or poorly fixed.


Asunto(s)
Helmintos , Nematodos , Panthera , Animales , Panthera/genética , México/epidemiología , ARN Ribosómico 28S/genética , Helmintos/genética
16.
Int J Parasitol ; 54(6): 279-301, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38452963

RESUMEN

Invasive snails are associated with ecological problems in freshwater bodies worldwide. However, their impact on the transmission of digenean infections remain underreported. In the present study, 1708 specimens representing four snail species were sampled from four impoundments in the Limpopo River system in South Africa. Gyraulus chinensis (Planorbidae), Physella acuta (Physidae) and Pseudosuccinea columella (Lymnaeidae), which are invasive, were found in all the sampling sites. In contrast, the native lymnaeid Radix natalensis occurred at only one study site. Digeneans were observed only from R. natalensis (prevalence = 49%) and Ps. columella (prevalence = 23%). Morphological and genetic analyses revealed four digeneans: Fasciola nyanzae, Orientocreadium sp., Petasiger sp. and Patagifer vioscai. Pseudosuccinea columella was infected by the four digeneans while R. natalensis harboured only Orientocreadium sp. and Petasiger sp. Partial sequences of Orientocreadium sp. from the current study differed from congeners whose DNA data are available on GenBank, by p-distances of at least 1.84 and 2.2% for 28S and the internal transcribed spacer (ITS) rDNA, respectively. Phylogenetic analyses demonstrated that the present species is sister to Orientocreadium batrachoides. Genetic and phylogenetic data based on 28S and ITS rDNA suggested that Petasiger sp. from the present study and isolates of three unidentified Petasiger spp. from Kenya, Hungary and Australia, were representatives of the same species. This is the first known report of Orientocreadium, Petasiger and Patagifer from Ps. columella. The occurrence of F. nyanzae in Ps. columella indicates spillback from R. natalensis. These findings echo the concerns raised in previous studies about the potential role of Ps. columella in the amplification of digenean diseases in its introduced range. Phylogenetic analyses of partial sequences of the cytochrome c oxidase subunit 1 mitochondrial gene (cox1) showed multiple lineages of Ps. columella in North and South America. Pseudosuccinea columella specimens from the present study belong to an invasive genotype that has spread globally and has been reported from Zimbabwe, Egypt, Portugal, Australia, Argentina, Colombia and New Mexico (USA). Physella acuta from the current study had a stronger genetic relationship with isolates from Canada and Iceland, than with isolates from other parts of Africa, suggesting several invasion routes into Africa. This is the first known DNA characterisation of G. chinensis from Africa. Phylogenetic reconstruction indicated multiple exit events of G. chinensis from Asia into Europe and Africa. South African isolates clustered in a recent branch containing isolates from the Czech Republic and Hong Kong, China. Considering the presence of invasive snails in all the sampling sites in the present study, it is necessary to investigate the factors that enhance their establishment and to monitor their effects on the native snail populations.


Asunto(s)
Filogenia , Trematodos , Animales , Sudáfrica , Trematodos/genética , Trematodos/clasificación , Trematodos/aislamiento & purificación , Caracoles/parasitología , Caracoles/genética , ADN de Helmintos/genética , Ríos/parasitología , Especies Introducidas , ARN Ribosómico 28S/genética , Análisis de Secuencia de ADN , ADN Ribosómico/genética
17.
Mycologia ; 116(3): 418-430, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38530332

RESUMEN

In 1895 and 2001, rust fungi affecting Licania trees (Chrysobalanchaceae) in Brazil were described as Uredo licaniae by Hennings in the state of Goiás and as Phakopsora tomentosae by Ferreira et al. in the state of Amazonas, respectively. Recently, a Licania rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome c oxidase subunit III (CO3) gene sequences. Since the original type specimen of Ph. tomentosae is considered lost, we carefully reviewed the type description and questioned the identity of the telium, which justified the description of the fungus as a Phakopsora species. Furthermore, the additional revision of the type material described by Hennings revealed that Ph. tomentosae is a synonym of U. licaniae. Based on the morphological examinations, disease symptoms, and shared hosts, we concluded that the newly collected material is conspecific with U. licaniae. However, the phylogenetic analyses rejected allocation in Phakopsora and instead assigned the Licania rust fungus in a sister relationship with Austropuccinia psidii (Sphaerophragmiaceae), the causal agent of the globally invasive myrtle rust pathogen. We therefore favored a recombination of U. licaniae (syn. Ph. tomentosae) into Austropuccinia and proposed the new name Austropuccina licaniae for the second species now identified for this genus. The fungus shares conspicuous symptoms with A. psidii, causing often severe infections of growing leaves and shoots that lead to leaf necrosis, leaf shedding, and eventually to the dieback of entire shoots. In view of the very similar symptoms of its aggressively invasive sister species, we briefly discuss the current state of knowledge about A. licaniae and the potential risks, and the opportunity of its identification.


Asunto(s)
Basidiomycota , ADN de Hongos , Filogenia , Enfermedades de las Plantas , Basidiomycota/genética , Basidiomycota/clasificación , Basidiomycota/aislamiento & purificación , Enfermedades de las Plantas/microbiología , ADN de Hongos/genética , Brasil , Análisis de Secuencia de ADN , ARN Ribosómico 28S/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Árboles/microbiología
18.
Parasitology ; 151(4): 440-448, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38525532

RESUMEN

A new species of Moniliformis, M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox1 and cox2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis, and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China.


Asunto(s)
Acantocéfalos , Filogenia , Tupaia , Animales , Tupaia/parasitología , Tupaia/genética , China , Acantocéfalos/genética , Acantocéfalos/clasificación , Acantocéfalos/anatomía & histología , Acantocéfalos/ultraestructura , Helmintiasis Animal/parasitología , Microscopía Electrónica de Rastreo/veterinaria , ADN de Helmintos/genética , ARN Ribosómico 18S/genética , Femenino , Masculino , ARN Ribosómico 28S/genética , Intestinos/parasitología
19.
Acta Parasitol ; 69(1): 898-909, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38472688

RESUMEN

OBJECTIVES: The present work aims to expand the knowledge of the digenean species Prosogonotrema bilabiatum (Sclerodistomidae), a parasite of Chaetodipterus faber (Acanthuriformes) from Brazil, with an integrative taxonomic approach, using light microscopy, scanning electron microscopy, histology, and molecular biology. METHODS: Forty-one digenean specimens were stained with hydrochloric carmine for morphological studies. Eleven parasites were dehydrated through a graded ethanol series, critical point dried with carbon dioxide, and coated with gold for scanning electron microscopy analysis. Four specimens were processed following histological routine and stained with hematoxylin and eosin and Gomori trichrome. DNA extracted was amplified using 28S partial primer D1-D3. Maximum likelihood and Bayesian inference were performed for phylogenetic analysis. RESULTS: Morphometric and morphological data of the specimens studied ranged in accordance as observed in previous descriptions of the species. Observations from scanning electron microscopy and histology corroborated with those observed in stained whole mounts. Molecular analysis showed that specimens of P. bilabiatum from Brazil clustered with another two sequences of this species from different hosts and localities, with a high node support value. CONCLUSIONS: The integrative taxonomic approach allowed to record and describe new characteristics of P. bilabiatum related to the tegument, the structure and the arrangement of its tissues. The use of molecular markers confirmed that specimens identified as P. bilabiatum from different hosts and localities are all conspecific. Further studies, mainly molecular with less conserved genetic markers, should be carried out to better understand the phylogenetic relationships of Prosogonotrema with Hemiuroidea.


Asunto(s)
Enfermedades de los Peces , Microscopía Electrónica de Rastreo , Filogenia , Trematodos , Infecciones por Trematodos , Animales , Brasil/epidemiología , Enfermedades de los Peces/parasitología , Trematodos/clasificación , Trematodos/genética , Trematodos/ultraestructura , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación , Microscopía Electrónica de Rastreo/veterinaria , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/veterinaria , Infecciones por Trematodos/epidemiología , Peces/parasitología , ADN de Helmintos/genética , ARN Ribosómico 28S/genética
20.
J Helminthol ; 98: e23, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38462988

RESUMEN

During an ecological study with a near-endangered anuran in Brazil, the Schmidt's Spinythumb frog, Crossodactylus schmidti Gallardo, 1961, we were given a chance to analyze the gastrointestinal tract of a few individuals for parasites. In this paper, we describe a new species of an allocreadiid trematode of the genus Creptotrema Travassos, Artigas & Pereira, 1928, which possesses a unique trait among allocreadiids (i.e., a bivalve shell-like muscular structure at the opening of the ventral sucker); the new species represents the fourth species of allocreadiid trematode parasitizing amphibians. Besides, the new species is distinguished from other congeners by the combination of characters such as the body size, ventral sucker size, cirrus-sac size, and by having small eggs. DNA sequences through the 28S rDNA and COI mtDNA further corroborated the distinction of the new species. Phylogenetic analyses placed the newly generated sequences in a monophyletic clade together with all other sequenced species of Creptotrema. Genetic divergences between the new species and other Creptotrema spp. varied from 2.0 to 4.2% for 28S rDNA, and 15.1 to 16.8% for COI mtDNA, providing robust validation for the recognition of the new species. Even though allocreadiids are mainly parasites of freshwater fishes, our results confirm anurans as hosts of trematodes of this family. Additionally, we propose the reallocation of Auriculostoma ocloya Liquin, Gilardoni, Cremonte, Saravia, Cristóbal & Davies, 2022 to the genus Creptotrema. This study increases the known diversity of allocreadiids and contributes to our understanding of their evolutionary relationships, host-parasite relationships, and biogeographic history.


Asunto(s)
Trematodos , Infecciones por Trematodos , Humanos , Animales , Infecciones por Trematodos/veterinaria , Infecciones por Trematodos/parasitología , Filogenia , Trematodos/genética , ADN Ribosómico/genética , ADN Ribosómico/química , Anuros , ADN Mitocondrial/genética , Brasil , ARN Ribosómico 28S/genética
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