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1.
Parasitol Int ; 86: 102473, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34600157

RESUMO

Despite the large number of species described to date for the onchoprotepcephalid genus Acanthobothrium (207), only 16 named species have a genetic sequence. With this background, specimens of adult cestodes of the stingray Hypanus longus were collected off San Blas, Nayarit, and onchoproteocephalid larvae in the carangid fish Trachinotus rhodopus from Puerto Ángel, Oaxaca, both located on the Pacific coast of Mexico. The objective of this work is to investigate the phylogenetic position of these adults and larvae using nuclear ribosomal markers (18S rDNA and 28S rDNA). Morphologically, adult specimens were identified as Acanthobothrium cleofanus; larvae were identified only to family level. The phylogenetic position of both taxa was investigated based on the information of two nuclear molecular markers analyzed under Parsimony (PA) and Bayesian Inference (BI) methods. The newly generated sequences of A. cleofanus from Nayarit are identical to the sequences of several samples of Acanthobothrium sp. collected in the Mexican Pacific, which sequence are available in GenBank; DNA sequences obtained from onchoproteocephalid larva clearly place this taxon within Acanthobothrium but representing an independent lineage. In the resulting phylogenetic trees, Uncibilocularis okei was found nested within Acanthobothrium with an unstable position depending on the optimality criteria, indicating the need for more molecular analyzes with a greater number of species of both genera prior to define its phylogenetic relationships.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Rajidae , Animais , Cestoides/genética , Cestoides/crescimento & desenvolvimento , Infecções por Cestoides/parasitologia , Marcadores Genéticos , Larva/classificação , Larva/crescimento & desenvolvimento , México , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análise
2.
Parasitol Int ; 86: 102449, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34481946

RESUMO

Trichinellosis is a potentially deadly parasitic zoonosis that is contracted by consuming undercooked infected meat. Reliable detection of infectious Trichinella spp. larvae in meat is therefore pivotal to ensure consumer's safety. The recently authorised PrioCHECK™ Trichinella Alternative Artificial Digestion (AAD) test kit appears promising when used with the standard magnetic stirrer method, but evaluation with other apparatus types is lacking. In this study, the performance of the AAD kit in an adapted Trichomatic-35 (TM35) instrument was evaluated, first, at the Swiss National Reference Laboratory for trichinellosis (NRL); second, in a ring trial involving four Swiss official laboratories. Proficiency pork samples spiked with larvae of Trichinella spiralis, T. britovi, or T. pseudospiralis were tested with the AAD kit and with the reference pepsin-HCl digestion method in TM35 instruments. At the NRL, both methods yielded identical qualitative and similar quantitative results independently of the Trichinella species. In the ring trial, satisfactory results were obtained for 47/50 (94.0%) (AAD) and 62/67 (92.5%) (reference method) of the analysed samples. Technical problems impairing analysis were more frequently observed with the AAD kit (n = 22) than with the reference method (n = 5) and were mainly (16/22) reported by one of the external labs. When no technical issues were recorded, the performance of both methods was comparable, in agreement with the observations at the NRL; however, these results suggest a need for further training with the kit and standardisation of the adapted TM35 instruments.


Assuntos
Testes Diagnósticos de Rotina/instrumentação , Parasitologia de Alimentos , Carne de Porco/parasitologia , Trichinella/isolamento & purificação , Animais , Larva/crescimento & desenvolvimento , Sensibilidade e Especificidade , Trichinella/crescimento & desenvolvimento , Trichinella spiralis/crescimento & desenvolvimento , Trichinella spiralis/isolamento & purificação
3.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34636890

RESUMO

Hexamerins are members of the hemocyanin superfamily and play essential roles in providing amino acids and energy for the nonfeeding stages of insects. In this study, we cloned and analyzed the expression patterns of four hexamerin genes (hex 70a, hex 70b, hex 70c, and hex 110) at different worker development stages and queen diapause statuses in the bumble bee, Bombus terrestris. The results of this study showed that hex 110 has the longest open reading frame (ORF; 3,297 bp) compared to the ORFs of hex 70a (2,034 bp), hex 70b (2,067 bp), and hex 70c (2,055 bp). The putative translation product of Hex 70a, Hex 70b, Hex70c, and Hex 110 has 677, 688, 684, and 1,098aa with predicted molecular mass of 81.13, 79.69, 81.58, and 119 kDa. In the development stages of workers, the expression levels of hex 70a, hex 70b, and hex 70c increased gradually from the larval stage and exhibited high expression levels at the pink eyed and brown eyed pupae stage, whereas hex 110 exhibited the highest expression level at the larval period. Four hexamerin genes were highly expressed at the prediapause status of queen (P < 0.05), and compared to the eclosion queen, the lowest upregulation was 3.7-fold, and the highest upregulation was 1,742-fold. The expression levels of hex 70b, hex 70c, and hex 110 at diapause were significantly higher than those at postdiapause (P < 0.05). In conclusion, hexamerins may play important roles in queen diapause and metamorphosis of larval and pupal stages.


Assuntos
Abelhas , Proteínas de Insetos/genética , Animais , Abelhas/genética , Abelhas/crescimento & desenvolvimento , Abelhas/fisiologia , Diapausa/genética , Diapausa/fisiologia , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Metamorfose Biológica/genética , Metamorfose Biológica/fisiologia , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/fisiologia
4.
PLoS One ; 16(10): e0255321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34634069

RESUMO

BACKGROUND: An. funestus is a major Afrotropical vector of human malaria. This study sought to investigate the larval ecology, sporozoite infection rates and blood meal sources of An. funestus in western Kenya. METHODS: Larval surveys were carried out in Bungoma (Highland) and Kombewa (lowland) of western Kenya. Aquatic habitats were identified, characterized, georeferenced and carefully examined for mosquito larvae and predators. Indoor resting mosquitoes were sampled using pyrethrum spray catches. Adults and larvae were morphologically and molecularly identified to species. Sporozoite infections and blood meal sources were detected using real-time PCR and ELISA respectively. RESULTS: Of the 151 aquatic habitats assessed, 62/80 (78%) in Bungoma and 58/71(82%) in Kombewa were positive for mosquito larvae. Of the 3,193 larvae sampled, An. funestus larvae constitute 38% (1224/3193). Bungoma recorded a higher number of An. funestus larvae (85%, 95%, CI, 8.722-17.15) than Kombewa (15%, 95%, CI, 1.33-3.91). Molecular identification of larvae showed that 89% (n = 80) were An. funestus. Approximately 59%, 35% and 5% of An. funestus larvae co-existed with An. gambiae s.l, Culex spp and An. coustani in the same habitats respectively. Of 1,221 An. funestus s.l adults sampled, molecular identifications revealed that An. funestus constituted 87% (n = 201) and 88% (n = 179) in Bungoma and Kombewa, respectively. The Plasmodium falciparum sporozoite rate of An. funestus in Bungoma and Kombewa was 2% (3/174) and 1% (2/157), respectively, and the human blood index of An. funestus was 84% (48/57) and 89% (39/44) and for Bungoma and Kombewa, respectively. CONCLUSION: Man-made ponds had the highest abundance of An. funestus larvae. Multiple regression and principal component analyses identified the distance to the nearest house as the key environmental factor associated with the abundance of An. funestus larvae in aquatic habitats. This study serves as a guide for the control of An. funestus and other mosquito species to complement existing vector control strategies.


Assuntos
Anopheles/embriologia , Larva/crescimento & desenvolvimento , Malária Falciparum/transmissão , Controle de Mosquitos/métodos , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/parasitologia , Animais , Anopheles/parasitologia , Ecologia , Humanos , Mosquiteiros Tratados com Inseticida , Inseticidas/farmacologia , Quênia , Larva/parasitologia , Plasmodium falciparum/isolamento & purificação
5.
Mar Biotechnol (NY) ; 23(5): 749-765, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34647196

RESUMO

We investigated a time-course larval transcriptional analysis (RNA-seq) in the longfin yellowtail Seriola rivoliana, from hatching to day four at 22 °C, without providing zooplankton as food. Larval starvation is a critical physiological stage that must be prevented to ensure survival. However, the transcriptional mechanisms to endure starvation have not been investigated in marine fish. Differential gene expression showed newly day-specific transcriptome events during larval development. On day 1 (yolk sac absorption), the predominant upregulated developmental processes were larval growth, muscle and vision development, cytoskeletal structure, protein synthesis, protein and fat digestion-absorption, and hormone biosynthesis, whereas the cell cycle was suppressed. On day 2 (yolk sac exhaustion), a new stage of energy regeneration (ATP) was supplied by the oil drop reserve, whereas protein digestion-absorption and growth were suppressed. On day 3 (mouth opening and starvation), stress signals and nutrition deprivation upregulated the p53 signal and triggered autophagy and the AMP-activated protein kinase (AMPK) pathways as an alternative catabolic pathway to enduring starvation, and the circadian rhythm was established. On day 4 (starving and weakened larvae condition), autophagy supported subsequent protein synthesis, activated the immune system, and promoted estrogen signaling and skeleton renovation. However, larvae suppressed muscle development, vision and carbohydrate, and fat digestion-absorption and became lethargic, evidencing limited physiological support by autophagy to maintain survival without exogenous nutrition in this species.


Assuntos
Privação de Alimentos , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Animais , Autofagia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Perciformes/genética , Transcriptoma
6.
Vet Res ; 52(1): 124, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593042

RESUMO

The parasitic gastrointestinal nematode Haemonchus contortus causes serious economic losses to agriculture due to infection and disease in small ruminant livestock. The development of new therapies requires appropriate viability testing, with methods nowadays relying on larval motility or development using procedures that involve microscopy. None of the existing biochemical methods, however, are performed in adults, the target stage of the anthelmintic compounds. Here we present a new test for the viability of H. contortus adults and exsheathed third-stage larvae which is based on a bioluminescent assay of ATP content normalized to total protein concentration measured using bicinchoninic acid. All the procedure steps were optimized to achieve maximal sensitivity and robustness. This novel method can be used as a complementary assay for the phenotypic screening of new compounds with potential antinematode activity in exsheathed third-stage larvae and in adult males. Additionally, it might be used for the detection of drug-resistant isolates.


Assuntos
Trifosfato de Adenosina/uso terapêutico , Hemoncose/veterinária , Haemonchus/isolamento & purificação , Medições Luminescentes/veterinária , Técnicas de Diagnóstico Molecular/veterinária , Doenças dos Ovinos/diagnóstico , Animais , Feminino , Hemoncose/diagnóstico , Hemoncose/parasitologia , Haemonchus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Medições Luminescentes/instrumentação , Masculino , Técnicas de Diagnóstico Molecular/instrumentação , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
7.
Zoolog Sci ; 38(5): 397-404, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34664914

RESUMO

Vulnerability of animals immediately after hatching may induce plasticity in early ontology that becomes important for subsequent survival and growth. Ezo salamanders (Hynobius retardatus) are amphibians inhabiting ponds in Hokkaido, Japan where ezo brown frogs (Rana pirica) spawn on occasion. The salamander larvae must achieve sufficient size in order to successfully capture frog tadpoles, and we examined whether the presence of tadpoles causes development of greater body and/or gape size in newly hatched salamander larvae, which will in turn result in advantageous future prey-predator interactions. To examine this hypothesis, we conducted three laboratory experiments to demonstrate the phenotypic plasticity of salamander hatchlings in response to the presence or absence of frog tadpoles and to screen the type of signals involved in the expression of the phenotypic plasticity. First, salamander hatchlings were reared alone or with tadpoles, and the growth and morphological traits of the hatchlings were compared. The results showed that hatchling larvae grew faster with a more developed gape in the presence of tadpoles. Next, to identify the type of signals inducing this plasticity, two separate experiments with manipulated chemical and visual signals from tadpoles were conducted. The findings showed that faster growth and a more developed gape were induced by chemical but not visual signals. This plasticity may be an adaptive strategy because it increases the likelihood of preying on tadpoles in future prey-predator interactions.


Assuntos
Adaptação Fisiológica , Urodelos/crescimento & desenvolvimento , Animais , Sinais (Psicologia) , Larva/crescimento & desenvolvimento , Larva/fisiologia , Boca/anatomia & histologia , Boca/crescimento & desenvolvimento , Comportamento Predatório , Ranidae , Urodelos/fisiologia , Água/química
8.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718646

RESUMO

A lipidomics approach based on liquid chromatography-tandem mass spectrometry (LC-MS) was applied to analyze the molecular-level mechanism of lipid deposition in Hermetia illucens (H. illucens) larvae fed food waste (FW) at different days of age. The H. illucens larvae reared on FW substrates generally became larger, heavier, and fatter at 5-15 d of age. A large amount of glycerolipids (GL) were deposited, while glycerophospholipids (GP), sphingolipids, and derivatized lipids became relatively less abundant during the growth stage of the larvae. Forty-three subclasses of 3,205 lipid molecules were identified in larvae, and 139 lipids (79 upregulated and 60 downregulated during larval growth and development) were identified as potential biomarkers (variable importance in projection > 1; P < 0.05). The differential lipids were mainly enriched in 19 metabolic pathways, of which 9 metabolic pathways related to lipids, including GL and GP metabolisms. The results demonstrate that the lipid composition and mechanisms changed during the growth and development stage of H. illucens larvae. To the best of our knowledge, this is the first work exploring the molecular-level mechanism of lipid deposition during the growth and development stage of H. illucens larvae. The findings provide novel information for determining and utilizing the nutritional value of H. illucens larvae.


Assuntos
Ração Animal , Dípteros , Metabolismo dos Lipídeos , Eliminação de Resíduos , Animais , Cromatografia Líquida , Dípteros/crescimento & desenvolvimento , Dípteros/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lipidômica/métodos , Espectrometria de Massas em Tandem
9.
Nutrients ; 13(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34684347

RESUMO

Inositol is a natural substance found widely in plants. It is used in therapies for many medical cases. The aim of this study was to determine the toxicity of myo-inositol (MI) and to investigate its potential hepatoprotective character. In the first part of the study, zebrafish embryos were incubated with 5, 10, 20, 40, 60, 80, and 100 mg/mL MI. Endpoints such as survivability, hatching rate, malformation, and mobility were evaluated. Our results demonstrated that the high doses of MI lead to increased mortality and malformations and reduce the hatching rate in comparison to the control group. Moreover, low doses of this compound do not produce a negative effect on zebrafish and even have the ability to increase the hatching rate and mobility. In the second part of the study, the hepatoprotective effect of MI was tested. Zebrafish larvae from the line Tg (fabp10a:DsRed) were incubated for 24 h with 1% and 2% ethanol (EtOH), 5 mg/mL of MI with 1% EtOH, and 5 mg/mL of MI with 2% EtOH. No significant differences between the groups with EtOH and the group treated with EtOH with MI were observed. Our results suggest that MI has no positive benefits on hepatocytes of zebrafish larvae.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Inositol/farmacologia , Fígado/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/efeitos dos fármacos , Etanol , Fluorescência , Inositol/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Fígado/patologia , Modelos Animais , Análise de Sobrevida , Testes de Toxicidade
10.
PLoS One ; 16(10): e0258235, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34679089

RESUMO

Carnivorous plants feed on animal prey, mainly insects, to get additional nutrients. This carnivorous syndrome is widely investigated and reported. In contrast, reports on herbivores feeding on carnivorous plants and related defenses of the plants under attack are rare. Here, we studied the interaction of a pitcher plant, Nepenthes x ventrata, with a generalist lepidopteran herbivore, Spodoptera littoralis, using a combination of LC/MS-based chemical analytics, choice and feeding assays. Chemical defenses in N. x ventrata leaves were analyzed upon S. littoralis feeding. A naphthoquinone, plumbagin, was identified in Nepenthes defense against herbivores and as the compound mainly responsible for the finding that S. littoralis larvae gained almost no weight when feeding on Nepenthes leaves. Plumbagin is constitutively present but further 3-fold increased upon long-term (> 1 day) feeding. Moreover, in parallel de novo induced trypsin protease inhibitor (TI) activity was identified. In contrast to TI activity, enhanced plumbagin levels were not phytohormone inducible, not even by defense-related jasmonates although upon herbivory their level increased more than 50-fold in the case of the bioactive jasmonic acid-isoleucine. We conclude that Nepenthes is efficiently protected against insect herbivores by naphthoquinones acting as phytoanticipins, which is supported by additional inducible defenses. The regulation of these defenses remains to be investigated.


Assuntos
Planta Carnívora/fisiologia , Herbivoria/fisiologia , Naftoquinonas/farmacologia , Compostos Fitoquímicos/farmacologia , Sarraceniaceae/fisiologia , Ácido Abscísico/farmacologia , Animais , Planta Carnívora/efeitos dos fármacos , Ciclopentanos/farmacologia , Dieta , Herbivoria/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/análise , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Inibidores de Proteases/farmacologia , Ácido Salicílico/farmacologia , Sarraceniaceae/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Spodoptera/fisiologia
11.
Malar J ; 20(1): 414, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34688298

RESUMO

BACKGROUND: Research on mosquito-microbe interactions may lead to new tools for mosquito and mosquito-borne disease control. To date, such research has largely utilized laboratory-reared mosquitoes that typically lack the microbial diversity of wild populations. A logical progression in this area involves working under controlled settings using field-collected mosquitoes or, in most cases, their progeny. Thus, an understanding of how laboratory colonization affects the assemblage of mosquito microbiota would aid in advancing mosquito microbiome studies and their applications beyond laboratory settings. METHODS: Using high throughput 16S rRNA amplicon sequencing, the internal and cuticle surface microbiota of F1 progeny of wild-caught adult Anopheles albimanus from four locations in Guatemala were characterized. A total of 132 late instar larvae and 135 2-5 day-old, non-blood-fed virgin adult females that were reared under identical laboratory conditions, were pooled (3 individuals/pool) and analysed. RESULTS: Results showed location-associated heterogeneity in both F1 larval internal (p = 0.001; pseudo-F = 9.53) and cuticle surface (p = 0.001; pseudo-F = 8.51) microbiota, and only F1 adult cuticle surface (p = 0.001; pseudo-F = 4.5) microbiota, with a more homogenous adult internal microbiota (p = 0.12; pseudo-F = 1.6) across collection sites. Overall, ASVs assigned to Leucobacter, Thorsellia, Chryseobacterium and uncharacterized Enterobacteriaceae, dominated F1 larval internal microbiota, while Acidovorax, Paucibacter, and uncharacterized Comamonadaceae, dominated the larval cuticle surface. F1 adults comprised a less diverse microbiota compared to larvae, with ASVs assigned to the genus Asaia dominating both internal and cuticle surface microbiota, and constituting at least 70% of taxa in each microbial niche. CONCLUSIONS: These results suggest that location-specific heterogeneity in filed mosquito microbiota can be transferred to F1 progeny under normal laboratory conditions, but this may not last beyond the F1 larval stage without adjustments to maintain field-derived microbiota. These findings provide the first comprehensive characterization of laboratory-colonized F1 An. albimanus progeny from field-derived mothers. This provides a background for studying how parentage and environmental conditions differentially or concomitantly affect mosquito microbiome composition, and how this can be exploited in advancing mosquito microbiome studies and their applications beyond laboratory settings.


Assuntos
Exoesqueleto/microbiologia , Anopheles/microbiologia , Microbiota , Animais , Anopheles/crescimento & desenvolvimento , Feminino , Guatemala , Larva/crescimento & desenvolvimento , Larva/microbiologia
12.
Nat Commun ; 12(1): 6181, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702841

RESUMO

The rhesus macaque provides a unique model of acquired immunity against schistosomes, which afflict >200 million people worldwide. By monitoring bloodstream levels of parasite-gut-derived antigen, we show that from week 10 onwards an established infection with Schistosoma mansoni is cleared in an exponential manner, eliciting resistance to reinfection. Secondary challenge at week 42 demonstrates that protection is strong in all animals and complete in some. Antibody profiles suggest that antigens mediating protection are the released products of developing schistosomula. In culture they are killed by addition of rhesus plasma, collected from week 8 post-infection onwards, and even more efficiently with post-challenge plasma. Furthermore, cultured schistosomula lose chromatin activating marks at the transcription start site of genes related to worm development and show decreased expression of genes related to lysosomes and lytic vacuoles involved with autophagy. Overall, our results indicate that enhanced antibody responses against the challenge migrating larvae mediate the naturally acquired protective immunity and will inform the route to an effective vaccine.


Assuntos
Schistosoma mansoni/fisiologia , Esquistossomose mansoni/imunologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Anticorpos Anti-Helmínticos/farmacologia , Antígenos de Helmintos/imunologia , Modelos Animais de Doenças , Epigênese Genética/efeitos dos fármacos , Feminino , Genes de Helmintos/genética , Granulócitos/imunologia , Histonas/metabolismo , Interações Hospedeiro-Parasita/imunologia , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Linfócitos/imunologia , Macaca mulatta/imunologia , Macaca mulatta/parasitologia , Masculino , Contagem de Ovos de Parasitas , Reinfecção/imunologia , Esquistossomose mansoni/parasitologia
13.
Zool Res ; 42(5): 637-649, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34472225

RESUMO

The insect brain is the central part of the neurosecretory system, which controls morphology, physiology, and behavior during the insect's lifecycle. Lepidoptera are holometabolous insects, and their brains develop during the larval period and metamorphosis into the adult form. As the only fully domesticated insect, the Lepidoptera silkworm Bombyx mori experienced changes in larval brain morphology and certain behaviors during the domestication process. Hormonal regulation in insects is a key factor in multiple processes. However, how juvenile hormone (JH) signals regulate brain development in Lepidoptera species, especially in the larval stage, remains elusive. We recently identified the JH receptor Methoprene tolerant 1 ( Met1) as a putative domestication gene. How artificial selection on Met1 impacts brain and behavioral domestication is another important issue addressing Darwin's theory on domestication. Here, CRISPR/Cas9-mediated knockout of Bombyx Met1 caused developmental retardation in the brain, unlike precocious pupation of the cuticle. At the whole transcriptome level, the ecdysteroid (20-hydroxyecdysone, 20E) signaling and downstream pathways were overactivated in the mutant cuticle but not in the brain. Pathways related to cell proliferation and specialization processes, such as extracellular matrix (ECM)-receptor interaction and tyrosine metabolism pathways, were suppressed in the brain. Molecular evolutionary analysis and in vitro assay identified an amino acid replacement located in a novel motif under positive selection in B. mori, which decreased transcriptional binding activity. The B. mori MET1 protein showed a changed structure and dynamic features, as well as a weakened co-expression gene network, compared with B. mandarina. Based on comparative transcriptomic analyses, we proposed a pathway downstream of JH signaling (i.e., tyrosine metabolism pathway) that likely contributed to silkworm larval brain development and domestication and highlighted the importance of the biogenic amine system in larval evolution during silkworm domestication.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bombyx/metabolismo , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Bombyx/crescimento & desenvolvimento , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Sistemas CRISPR-Cas , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Proteínas de Insetos/genética , Tegumento Comum/fisiologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Filogenia , Conformação Proteica
14.
Insect Biochem Mol Biol ; 138: 103636, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34478812

RESUMO

There are several known non-molting mutations of the silkworm, Bombyx mori, including non-molting dwarf (nm-d). Larvae with this mutation hatch normally and start eating leaves, but die before the completion of the first ecdysis. Genetic analysis of the nm-d mutation would contribute to the isolation of essential genes for the larval development of lepidopteran insects. To identify the causative gene of the nm-d locus, we conducted RNA-seq based rough mapping. Using two sets of RNA-seq data, one from a pooled sample of normal larvae, and one from a pooled sample of nm-d larvae, the nm-d locus was narrowed to a 500 kb region. Among the genes located in this region, a nm-d-specific exon loss was identified in the Bombyx homolog of the ATIC (5-aminoimidazole-4-carboxamide ribonucleotide transformylase/Inosine 5'-monophosphate cyclohydrolase) (BmATIC) gene, which catalyzes the final two steps of the de novo purine biosynthetic pathway in mammals. PCR and subsequent sequencing analysis revealed that a region containing exon 9 of the BmATIC gene is deleted in the nm-d larvae. A knockout allele of the BmATIC gene (BmATICKO), that was generated using the CRISPR/Cas9 system, revealed that first instar knockout larvae died while exhibiting the dark brown larval body that is a typical feature of mutants that lack uric acid in the integument. Lethal larvae resulted from crosses between +/BmATICKO moths. The uric acid content in the whole-body of the first instar was drastically reduced in the nm-d larvae compared to normal larvae. These results indicated that the BmATIC gene is responsible for the nm-d phenotype, and that nm-d larvae have a defect in purine biosynthesis, including uric acid. We also discuss the possibility that the BmATIC mRNA is maternally transmitted to eggs. Our results indicated that RNA-seq based mapping using pooled samples is a practical method for the identification of the causative genes of lethal mutations.


Assuntos
Proteínas de Insetos/genética , Mariposas/metabolismo , Mutação , Purinas/biossíntese , Animais , Proteínas de Insetos/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Mariposas/genética , Mariposas/crescimento & desenvolvimento
15.
Arch Insect Biochem Physiol ; 108(3): e21840, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34569086

RESUMO

Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), the cotton bollworm, is a destructive pest which is famous for its resistance to a variety of insecticides. RNA interference is a posttranscriptional gene silencing mechanism that has become a popular tool to control insect pests, triggered by double-stranded RNAs (dsRNAs). The effect of ingestion and injection delivery methods of dsRNA related to some protease genes including Trypsin (Ha-TRY39 and Ha-TRY96), Chymotrypsin (Ha-CHY), and Cathepsin L (Ha-CAT) on growth and development of H. armigera was investigated in this study. All protease genes encoded full ORFs and were expressed in all H. armigera larvae stages and tissues. In both injection and feeding bioassays, Ha-RNAi CHY's performance outperformed that of other protease genes. CHY enzyme activity in the midgut of larvae was significantly reduced after treatment with ds-HaCHY. Oral administration of ds-CHY also resulted in significant mortality of H. armigera larvae. However, because of the high RNase activity in the midgut lumen of lepidoptera, a large amount of dsRNA was needed to effectively kill instars of H. armigera. To reduce dsRNA degradation, bacterial expression and dsRNA formulation were used. After oral administration, it was toxic to H. armigera larvae. Before oral administration, bacterial cells were sonicated to increase dsRNA release. The RNA interference efficiency of sonicated bacteria was significantly increased, resulting in higher larval mortality when administered orally. All of these findings point to Ha-CHY as a new candidate for developing an effective dsRNA-based pesticide for H. armigera control.


Assuntos
Mariposas , Peptídeo Hidrolases , RNA de Cadeia Dupla/farmacologia , Animais , Bactérias/genética , Catepsinas/efeitos dos fármacos , Catepsinas/genética , Quimotripsina/efeitos dos fármacos , Quimotripsina/genética , Proteínas de Insetos/genética , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Mortalidade , Mariposas/efeitos dos fármacos , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Organismos Geneticamente Modificados , Peptídeo Hidrolases/efeitos dos fármacos , Peptídeo Hidrolases/genética , Controle de Pragas/métodos , Interferência de RNA , RNA de Cadeia Dupla/biossíntese , RNA de Cadeia Dupla/metabolismo , Tripsina/efeitos dos fármacos , Tripsina/genética
16.
PLoS One ; 16(9): e0257792, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34559852

RESUMO

Spray-dried animal plasma (SDP) in feed for several animal species provides health benefits, but research about use of SDP in shrimp feed is very limited. The objectives of the present study were to investigate the effects of dietary SDP on growth performance, feed utilization, immune responses, and prevention of Vibrio parahaemolyticus infection in Pacific white shrimp (Litopenaeus vannamei). In Experiment 1, the post-larvae were divided into five groups (four tank/group and 80 shrimp/tank) and fed four times daily diets with porcine SDP at 0, 1.5, 3, 4.5, and 6% of the diet for 45 days. In Experiment 2, the surviving shrimp from Experiment 1 were redistributed into six groups: four SDP groups as in Experiment 1 plus the positive and negative controls (four tank/group and 30 shrimp/tank). They were then challenged with V. parahaemolyticus by immersion at 105 colony-forming units (CFU)/mL and were fed with the same diets for another 4 days. In Experiment 1, shrimp fed 4.5% or 6% SDP diets had significantly higher body weight, survival rate, and improved feed conversion ratio. The immune parameters (total hemocyte count and phagocytic, phenoloxidase, and superoxide dismutase activities) of the shrimp fed 3-6% SDP diets also showed significant enhancement compared to the control. In Experiment 2, the survival rates of the 3-6% SDP groups were significantly higher than the positive control at day 4 after the immersion challenge. Likewise, the histopathological study revealed milder signs of bacterial infection in the hepatopancreas of the 3-6% SDP groups compared to the challenged positive control and 1.5% SDP groups. In conclusion, shrimp fed diets with SDP, especially at 4.5-6% of the diet, showed significant improvement in overall health conditions and better resistance to V. parahaemolyticus infection.


Assuntos
Suplementos Nutricionais/análise , Resistência à Doença , Penaeidae/crescimento & desenvolvimento , Plasma/química , Vibrio parahaemolyticus/imunologia , Ração Animal/análise , Animais , Peso Corporal , Hemócitos/metabolismo , Imunidade Inata , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/virologia , Penaeidae/imunologia , Penaeidae/virologia , Fagócitos/metabolismo , Secagem por Atomização , Suínos
17.
Ticks Tick Borne Dis ; 12(6): 101820, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555711

RESUMO

Ticks are vectors of a wide range of zoonotic viruses of medical and veterinary importance. Recently, metagenomics studies demonstrated that they are also the source of potentially pathogenic novel viruses. During the period from 2015 to 2017, questing ticks were collected by dragging the vegetation from geographically distant locations in the Republic of Korea (ROK) and a target-independent high-throughput sequencing method was utilized to study their virome. A total of seven viruses, including six putative novel viral entities, were identified. Genomic analysis showed that the novel viruses were most closely related to members in the orders Jingchuvirales and Bunyavirales. Phylogenetic reconstruction showed that the Bunyavirales-like viruses grouped in the same clade with other viruses within the Nairovirus and Phlebovirus genera, while the novel Jingchuvirales-like virus grouped together with other viruses within the family Chuviridae. Real-time RT-PCR was used to determine the geographic distribution and prevalence of these viruses in adult ticks. These novel viruses have a wide geographic distribution in the ROK with prevalences ranging from 2% to 18%. Our study expands the knowledge about the composition of the tick virome and highlights the wide diversity of viruses they harbor in the ROK. The discovery of novel viruses associated with ticks in the ROK highlights the need for an active tick-borne disease surveillance program to identify possible reservoirs of putative novel human pathogens.


Assuntos
Ixodidae/virologia , Vírus/isolamento & purificação , Animais , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/virologia , Ninfa/crescimento & desenvolvimento , Ninfa/virologia , República da Coreia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/transmissão , Doenças Transmitidas por Carrapatos/virologia
18.
Ticks Tick Borne Dis ; 12(6): 101824, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34520994

RESUMO

Brazilian spotted fever (BSF) is an acute infectious disease caused by the bacterium Rickettsia rickettsii, which is transmitted by different tick species. Due to deleterious effects caused on ticks, the horizontal transmission of R. rickettsii through amplifying hosts is crucial for its maintenance in tick populations among BSF-endemic areas. The tick Amblyomma aureolatum is the main vector of R. rickettsii in the São Paulo metropolitan area; nevertheless, it is not known which vertebrate could act as an amplifying host for this tick species. Herein, we evaluated the potential of domestic dogs - primary hosts for A. aureolatum adults in BSF-endemic areas - to act as amplifying hosts. For this purpose, A. aureolatum non-infected adults were allowed to feed on two groups of dogs: the control group (G1), composed of one dog not exposed to R. rickettsii; and, the infected group (G2), composed of three dogs infected with R. rickettsii via tick parasitism. All G2-dogs became ill, seroconverted to R. rickettsii, and rickettsial DNA was detected in 87% of the engorged females that fed on them. Transovarial transmission rate was estimated to be 25% and infected larvae successfully transmitted R. rickettsii to guinea-pigs, confirming transovarial transmission and vector competence. No rickettsial DNA was detected in individual samples of eggs or larvae, which precluded the estimation of filial infection rate, but implies that it was low. Our results suggest that domestic dogs act as amplifying hosts of R. rickettsii for A. aureolatum ticks in BSF-endemic areas in Brazil.


Assuntos
Amblyomma/microbiologia , Zoonoses Bacterianas/transmissão , Doenças do Cão/transmissão , Interações Hospedeiro-Patógeno , Infecções por Rickettsia/veterinária , Rickettsia rickettsii/fisiologia , Animais , Zoonoses Bacterianas/microbiologia , Brasil , Doenças do Cão/microbiologia , Cães , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/transmissão
19.
Insect Biochem Mol Biol ; 138: 103648, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34536505

RESUMO

Baculoviruses are double-stranded DNA entomopathogenic viruses that infect predominantly insects of the order Lepidoptera. Research in the last decade has started to disentangle the mechanisms underlying the insect-virus interaction, particularly focusing on the effects of the baculovirus infection in the host's physiology. Among crucial physiological functions, olfaction has a key role in reproductive tasks, food source detection and enemy avoidance. In this work, we describe that Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) induces expression changes in some odorant receptors (ORs) - the centrepiece of insect's olfaction - when infecting larvae from its natural host Spodoptera exigua (Lepidoptera: Noctuidae). Different ORs are up-regulated in larvae after SeMNPV infection, and two of them, SexiOR35 and SexiOR23, were selected for further functional characterization by heterologous expression in empty neurons of Drosophila melanogaster coupled to single-sensillum recordings. SexiOR35 appears to be a broadly tuned receptor able to recognise multiple and different chemical compounds. SexiOR23, although correctly expressed in Drosophila neurons, did not display any significant response to a panel of 58 stimuli. Behavioural experiments revealed that larvae infected by SeMNPV exhibit altered olfactory-driven behaviour to diet when it is supplemented with the plant volatiles linalool or estragole, two of the main SexiOR35 ligands, supporting the hypothesis that viral infection triggers changes in host perception through changes in the expression level of specific ORs.


Assuntos
Proteínas de Insetos/fisiologia , Nucleopoliedrovírus/fisiologia , Receptores Odorantes/fisiologia , Spodoptera/fisiologia , Animais , Drosophila melanogaster/fisiologia , Drosophila melanogaster/virologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Larva/virologia , Neurônios/fisiologia , Neurônios/virologia , Spodoptera/crescimento & desenvolvimento , Spodoptera/virologia
20.
Ticks Tick Borne Dis ; 12(6): 101818, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34537543

RESUMO

Rhipicephalus microplus is posing a serious threat to productive animal husbandry. Excessive use of synthetic chemicals in tick management has led to the development of resistant tick populations. Characterization of resistance to deltamethrin, cypermethrin, coumaphos and ivermectin in ticks is necessary to develop a suitable and sustainable control strategy. Based on adult immersion test and larval packet test, the resistance ratios (RR50) for adults and larvae of R. microplus populations from two Indian states ranged from 3.8 to 19.4 and 1.35-25.0 against deltamethrin, 0.061-26.3 and 0.22-19.2 against cypermethrin, and 0.2-9.5 and 0.01-3.1 against coumaphos, respectively, were recorded. Moreover, the RR50 for adults ranged from 0.212 to 3.87 against ivermectin. The RR50 for different acaricides was significantly (p<0.01) correlated with esterases, Glutathione S-transferase and monooxygenase activity. A point mutation at the 190th position of the domain II S4-5 linker region of the sodium channel gene in synthetic pyrethroids (SP) resistant populations was also detected. An antitick natural formulation prepared from the plant Azeratum conyzoides and containing two major compounds, Precocene-I (7­methoxy-2, 2-dimethyl 2H-chromene) and Precocene II (6, 7-dimethoxy-2, 2-dimethyl- 3-chromene), was developed and tested against the resistant ticks. The LC50 values of the natural formulation against the resistant populations were in the range of 4.31-5.33% irrespective of their RR50 values. Multi-acaricide resistant populations of R. microplus are established in India and the A. conyzoides based natural formulation can be used for its management.


Assuntos
Acaricidas/farmacologia , Ageratum/química , Rhipicephalus/efeitos dos fármacos , Animais , Cumafos/farmacologia , Resistência a Medicamentos , Feminino , Índia , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Nitrilas/farmacologia , Piretrinas/farmacologia , Rhipicephalus/crescimento & desenvolvimento
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