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1.
Sci Rep ; 12(1): 1903, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115663

RESUMO

Xenopus laevis tadpoles possess high regenerative ability and can regenerate functional tails after amputation. An early event in regeneration is the induction of undifferentiated cells that form the regenerated tail. We previously reported that interleukin-11 (il11) is upregulated immediately after tail amputation to induce undifferentiated cells of different cell lineages, indicating a key role of il11 in initiating tail regeneration. As Il11 is a secretory factor, Il11 receptor-expressing cells are thought to mediate its function. X. laevis has a gene annotated as interleukin 11 receptor subunit alpha on chromosome 1L (il11ra.L), a putative subunit of the Il11 receptor complex, but its function has not been investigated. Here, we show that nuclear localization of phosphorylated Stat3 induced by Il11 is abolished in il11ra.L knocked-out culture cells, strongly suggesting that il11ra.L encodes an Il11 receptor component. Moreover, knockdown of il11ra.L impaired tadpole tail regeneration, suggesting its indispensable role in tail regeneration. We also provide a model showing that Il11 functions via il11ra.L-expressing cells in a non-cell autonomous manner. These results highlight the importance of il11ra.L-expressing cells in tail regeneration.


Assuntos
Proliferação de Células , Subunidade alfa de Receptor de Interleucina-11/metabolismo , Larva/metabolismo , Regeneração , Cauda/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento , Interleucina-11/farmacologia , Subunidade alfa de Receptor de Interleucina-11/agonistas , Subunidade alfa de Receptor de Interleucina-11/genética , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Fosforilação , Regeneração/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Cauda/efeitos dos fármacos , Cauda/embriologia , Proteínas de Xenopus/genética , Xenopus laevis/embriologia , Xenopus laevis/genética
2.
Development ; 149(4)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35179181

RESUMO

The epicardium is a mesothelial tissue layer that envelops the heart. Cardiac injury activates dynamic gene expression programs in epicardial tissue, which in zebrafish enables subsequent regeneration through paracrine and vascularizing effects. To identify tissue regeneration enhancer elements (TREEs) that control injury-induced epicardial gene expression during heart regeneration, we profiled transcriptomes and chromatin accessibility in epicardial cells purified from regenerating zebrafish hearts. We identified hundreds of candidate TREEs, which are defined by increased chromatin accessibility of non-coding elements near genes with increased expression during regeneration. Several of these candidate TREEs were incorporated into stable transgenic lines, with five out of six elements directing injury-induced epicardial expression but not ontogenetic epicardial expression in larval hearts. Whereas two independent TREEs linked to the gene gnai3 showed similar functional features of gene regulation in transgenic lines, two independent ncam1a-linked TREEs directed distinct spatiotemporal domains of epicardial gene expression. Thus, multiple TREEs linked to a regeneration gene can possess either matching or complementary regulatory controls. Our study provides a new resource and principles for understanding the regulation of epicardial genetic programs during heart regeneration. This article has an associated 'The people behind the papers' interview.


Assuntos
Elementos Facilitadores Genéticos/genética , Coração/fisiologia , Pericárdio/metabolismo , Regeneração/fisiologia , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Cromatina/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica , Larva/crescimento & desenvolvimento , Larva/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Pericárdio/citologia , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
3.
Molecules ; 27(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35163928

RESUMO

The aim of this study was to investigate and compare in detail both the antifungal activity in vitro (with planktonic and biofilm-forming cells) and the essential oil composition (EOs) of naturally growing (OMN) and cultivated (OMC) samples of Origanum majorana L. (marjoram). The essential oil composition was analyzed using GC-MS. The major constituent of both EOs was carvacrol: 75.3% and 84%, respectively. Both essential oils showed high antifungal activity against clinically relevant Candida spp. with IC50 and IC90 less than or equal to 0.5 µg mL-1 and inhibition of biofilm with a concentration of 3.5 µg mL-1 or less. Cultivated marjoram oil showed higher anti-biofilm activity against C. albicans. In addition, OMC showed greater inhibition of germ-tube formation (inhibition by 83% in Spider media), the major virulence factor of C. albicans at a concentration of 0.125 µg mL-1. Both EOs modulated cell surface hydrophobicity (CSH), but OMN proved to be more active with a CSH% up to 58.41%. The efficacy of O. majorana EOs was also investigated using Galleria mellonella larvae as a model. It was observed that while the larvae of the control group infected with C. albicans (6.0 × 108 cells) and not receiving treatment died in the controls carried out after 24 h, all larvae in the infected treatment group survived at the end of the 96th hour. When the treatment group and the infected group were evaluated in terms of vital activities, it was found that the difference was statistically significant (p < 0.001). The infection of larvae with C. albicans and the effects of O. majorana EOs on the hemocytes of the model organism and the blastospores of C. albicans were evaluated by light microscopy on slides stained with Giemsa. Cytological examination in the treatment group revealed that C. albicans blastospores were phagocytosed and morphological changes occurred in hemocytes. Our results indicated that the essential oil of both samples showed strong antifungal activities against planktonic and biofilm-forming C. albicans cells and also had an influence on putative virulence factors (germ-tube formation and its length and on CSH).


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Óleos Voláteis/farmacologia , Origanum/química , Óleos Vegetais/farmacologia , Animais , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Testes de Toxicidade
4.
Molecules ; 27(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35164082

RESUMO

According to the concept of circular economy, insects represent good candidates as aquafeed ingredients. Nevertheless, there are some potential chemical risks linked with insect consumption. In this study, we reared the teleost Danio rerio, used as an experimental model, with five experimental diets characterized by increasing levels (0%, 25%, 50%, 75%, and 100%) of full-fat Hermetia illucens (Hi) prepupae, substituting for fish meal (FM) and fish oil (FO). We investigated the presence of potentially toxic elements (PTEs) Cd, Pb, Ni, As, and Hg in larval (20 days), juvenile (2 months), and adult (6 months) fish. Quantitative determinations of Cd, Pb, Ni, and As were made with an atomic absorption spectrometer; the total mercury content was determined by a direct mercury analyzer. The substitution of FM and FO with Hermetia illucens meal led to a reduction in the content of some PTEs, such as Pb, As, and Ni, in fishfeed, leading to concentrations below the legal limit of undesirable substances in animal feed. By increasing the Hi meal dietary content, we observed in the Danio rerio specimens an increase in Cd, Pb, and Ni content and a reduction in As content for all life stages. Moreover, a general increase in the content of Cd, Pb, Hg, and Ni from larvae to juvenile was measured, while the shift of Danio rerio from the juvenile to the adult stage involved a significant increase in the content of Pb, Hg, and Ni. Larvae had a reduced ability to bioaccumulate metal(loid)s compared to juveniles and adults. In conclusion, the content of PTEs in Danio rerio is influenced both by the type of diet administered and by the life stage of the animal itself. This research demonstrates the possibility of using Hi prepupae as an aquafeed ingredient without exposing fish to a chemical risk and, in perspective, allows applying these eco-sustainable diets for the breeding of edible fish species, without endangering human health.


Assuntos
Ração Animal/análise , Insetos , Metais Pesados/análise , Peixe-Zebra/crescimento & desenvolvimento , Animais , Aquicultura , Insetos/química , Larva/química , Larva/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
5.
Molecules ; 27(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35164372

RESUMO

2,6-dialkylpiperideines found in the venom of Solenopsis (Hymenoptera, Formicidae) fire ants are a range of compounds possessing various biological activities. A series of racemic 2-methyl-6-alkyl-Δ1,6-piperideines were synthesized for chemical confirmation of the natural products found in fire ant venom, and the evaluation of their biological activity. Synthetic Δ1,6-piperideines and the natural compounds in the cis-alkaloid fraction of Solenopsis invicta had identical mass spectra and retention times. Their insecticidal activities against the third-instar larvae of cotton bollworm (Helicoverpa armigera) were evaluated by using injection and topical application methods. All three compounds exhibited no lethal effect at concentrations of 0.05-0.4 mol/L by topical treatment, but moderate lethal effect at 0.4 mol/L through injection treatment. Compound 6a showed significantly higher activity than the natural insecticide nicotine. The differences in activity among compounds 6b, 6c and nicotine were not significant. The elongation of the carbon chain at the 6-position of the piperideine ring appears to decrease insecticidal activity.


Assuntos
Alcaloides/farmacologia , Venenos de Formiga/farmacologia , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Piperidinas/química , Piperidinas/farmacologia , Animais , Inseticidas/síntese química , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento
6.
PLoS One ; 17(2): e0263677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35143580

RESUMO

Spodoptera frugiperda (J.E. Smith) is a highly invasive noctuid pest first reported in northern Australia during early 2020. To document current status of resistance in S. frugiperda in Australia, insecticide toxicity was tested in field populations collected during the first year of establishment, between March 2020 and March 2021. Dose-response was measured by larval bioassay in 11 populations of S. frugiperda and a susceptible laboratory strain of Helicoverpa armigera. Emamectin benzoate was the most efficacious insecticide (LC50 0.023µg/ml) followed by chlorantraniliprole (LC50 0.055µg/ml), spinetoram (LC50 0.098µg/ml), spinosad (LC50 0.526µg/ml), and methoxyfenozide (1.413µg/ml). Indoxacarb was the least toxic selective insecticide on S. frugiperda (LC50 3.789µg/ml). Emamectin benzoate, chlorantraniliprole and methoxyfenozide were 2- to 7-fold less toxic on S. frugiperda compared with H. armigera while spinosyns were equally toxic on both species. Indoxacarb was 28-fold less toxic on S. frugiperda compared with H. armigera. There was decreased sensitivity to Group 1 insecticides and synthetic pyrethroids in S. frugiperda compared with H. armigera: toxicity was reduced up to 11-fold for methomyl, 56 to 199-fold for cyhalothrin, and 44 to 132-fold for alpha cypermethrin. Synergism bioassays with metabolic inhibitors suggest involvement of mixed function oxidase in pyrethroid resistance. Recommended diagnostic doses for emamectin benzoate, chlorantraniliprole, spinetoram, spinosad, methoxyfenozide and indoxacarb are 0.19, 1.0, 0.75, 6, 12 and 48µg/µl, respectively.


Assuntos
Resistência a Inseticidas , Inseticidas/toxicidade , Oxigenases de Função Mista/metabolismo , Spodoptera/crescimento & desenvolvimento , Animais , Austrália , Combinação de Medicamentos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hidrazinas/toxicidade , Proteínas de Insetos/metabolismo , Ivermectina/análogos & derivados , Ivermectina/toxicidade , Hormônios Juvenis/toxicidade , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Macrolídeos/toxicidade , Oxazinas/toxicidade , Vigilância da População , Spodoptera/efeitos dos fármacos , Spodoptera/enzimologia , ortoaminobenzoatos/toxicidade
7.
Sci Rep ; 12(1): 2056, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136137

RESUMO

Drosophila melanogaster tumor models are growing in popularity, driven by the high degree of genetic as well as functional conservation to humans. The most common method to measure the effects of a tumor on distant organs of a human cancer patient is to use computed tomography (CT), often used in diagnosing cachexia, a debilitating cancer-induced syndrome most visibly characterized by loss of muscle mass. Successful application of high resolution micro-CT scanning of D. melanogaster was recently reported and we here present the segmentation of all visible larval organs at several stages of tumor development. We previously showed the strong expected reduction in muscle mass as the tumor develops, and we here report a surprisingly strong reduction also in gut and Malpighian tubules (kidney) volume. Time-point of tumor development was found to have a stronger correlation to cachectic organ volume loss than tumor volume, giving support to the previously proposed idea that tumor size does not directly determine degree of cachexia.


Assuntos
Caquexia/patologia , Drosophila melanogaster/genética , Trato Gastrointestinal/patologia , Túbulos de Malpighi/patologia , Neoplasias/patologia , Animais , Modelos Animais de Doenças , Drosophila melanogaster/embriologia , Drosophila melanogaster/crescimento & desenvolvimento , Humanos , Larva/crescimento & desenvolvimento , Tamanho do Órgão/fisiologia , Microtomografia por Raio-X
8.
Development ; 149(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35129199

RESUMO

Skeletal elements frequently associate with vasculature and somatosensory nerves, which regulate bone development and homeostasis. However, the deep, internal location of bones in many vertebrates has limited in vivo exploration of the neurovascular-bone relationship. Here, we use the zebrafish caudal fin, an optically accessible organ formed of repeating bony ray skeletal units, to determine the cellular relationship between nerves, bones and endothelium. In adult zebrafish, we establish the presence of somatosensory axons running through the inside of the bony fin rays, juxtaposed with osteoblasts on the inner hemiray surface. During development we show that the caudal fin progresses through sequential stages of endothelial plexus formation, bony ray addition, ray innervation and endothelial remodeling. Surprisingly, the initial stages of fin morphogenesis proceed normally in animals lacking either fin endothelium or somatosensory nerves. Instead, we find that sp7+ osteoblasts are required for endothelial remodeling and somatosensory axon innervation in the developing fin. Overall, this study demonstrates that the proximal neurovascular-bone relationship in the adult caudal fin is established during fin organogenesis and suggests that ray-associated osteoblasts pattern axons and endothelium.


Assuntos
Nadadeiras de Animais/fisiologia , Axônios/metabolismo , Endotélio/metabolismo , Organogênese/fisiologia , Peixe-Zebra/crescimento & desenvolvimento , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Endotélio/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator de Transcrição Sp7/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Development ; 149(4)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35142351

RESUMO

The zebrafish has become a widely used animal model due, in large part, to its accessibility to and usefulness for high-resolution optical imaging. Although zebrafish research has historically focused mostly on early development, in recent years the fish has increasingly been used to study regeneration, cancer metastasis, behavior and other processes taking place in juvenile and adult animals. However, imaging of live adult zebrafish is extremely challenging, with survival of adult fish limited to a few tens of minutes using standard imaging methods developed for zebrafish embryos and larvae. Here, we describe a new method for imaging intubated adult zebrafish using a specially designed 3D printed chamber for long-term imaging of adult zebrafish on inverted microscope systems. We demonstrate the utility of this new system by nearly day-long observation of neutrophil recruitment to a wound area in living double-transgenic adult casper zebrafish with fluorescently labeled neutrophils and lymphatic vessels, as well as intubating and imaging the same fish repeatedly. We also show that Mexican cavefish can be intubated and imaged in the same way, demonstrating this method can be used for long-term imaging of adult animals from diverse aquatic species.


Assuntos
Microscopia de Fluorescência/métodos , Peixe-Zebra/anatomia & histologia , Animais , Animais Geneticamente Modificados/imunologia , Animais Geneticamente Modificados/metabolismo , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/metabolismo , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Neutrófilos/citologia , Neutrófilos/imunologia , Neutrófilos/patologia , Impressão Tridimensional , Imagem com Lapso de Tempo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
10.
Sci Rep ; 12(1): 240, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997149

RESUMO

Regional optimisation of malaria vector control approaches requires detailed understanding both of the species composition of Anopheles mosquito communities, and how they vary over spatial and temporal scales. Knowledge of vector community dynamics is particularly important in settings where ecohydrological conditions fluctuate seasonally and inter-annually, such as the Barotse floodplain of the upper Zambezi river. DNA barcoding of anopheline larvae sampled in the 2019 wet season revealed the predominance of secondary vector species, with An. coustani comprising > 80% of sampled larvae and distributed ubiquitously across all ecological zones. Extensive larval sampling, plus a smaller survey of adult mosquitoes, identified geographic clusters of primary vectors, but represented only 2% of anopheline larvae. Comparisons with larval surveys in 2017/2018 and a contemporaneous independent 5-year dataset from adult trapping corroborated this paucity of primary vectors across years, and the consistent numerical dominance of An. coustani and other secondary vectors in both dry and wet seasons, despite substantial inter-annual variation in hydrological conditions. This marked temporal consistency of spatial distribution and anopheline community composition presents an opportunity to target predominant secondary vectors outdoors. Larval source management should be considered, alongside prevalent indoor-based approaches, amongst a diversification of vector control approaches to more effectively combat residual malaria transmission.


Assuntos
Anopheles/genética , Mosquitos Vetores/genética , Distribuição Animal , Animais , Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Anopheles/fisiologia , Feminino , Inundações , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Malária , Masculino , Controle de Mosquitos , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/fisiologia , Filogenia , Estações do Ano , Zâmbia
11.
Sci Rep ; 12(1): 219, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997157

RESUMO

A germ-free rearing system is a crucial method for host-microbiota interactions using Nasonia as a model system. The previous rearing media in 2012 introduced toxic factors like bleach and antibiotics, required significant effort and volume of media preparation, and the rearing protocols in 2012 and 2016 often resulted in embryos, larvae, and enclosing pupae drowning, underfed, or desiccating. In this work, we optimize the germ-free rearing media that excludes the toxic factors and provide a substrate for the developing animals to have constant access to media without the risk of drowning or desiccation. The new process resulted in an increase in full maturation of larvae to adults from 33 to 65%, with no effect on the rate of growth or final adult size. This significantly improves the applicability of germ-free rearing of Nasonia and potentially other parasitoids.


Assuntos
Dípteros/crescimento & desenvolvimento , Entomologia/métodos , Animais , Feminino , Vida Livre de Germes , Interações entre Hospedeiro e Microrganismos , Larva/crescimento & desenvolvimento , Masculino , Pupa/crescimento & desenvolvimento
12.
Sci Rep ; 12(1): 698, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027639

RESUMO

Protease inhibitors (PIs) are important biotechnological tools of interest in agriculture. Usually they are the first proteins to be activated in plant-induced resistance against pathogens. Therefore, the aim of this study was to characterize a Theobroma cacao trypsin inhibitor called TcTI. The ORF has 740 bp encoding a protein with 219 amino acids, molecular weight of approximately 23 kDa. rTcTI was expressed in the soluble fraction of Escherichia coli strain Rosetta [DE3]. The purified His-Tag rTcTI showed inhibitory activity against commercial porcine trypsin. The kinetic model demonstrated that rTcTI is a competitive inhibitor, with a Ki value of 4.08 × 10-7 mol L-1. The thermostability analysis of rTcTI showed that 100% inhibitory activity was retained up to 60 °C and that at 70-80 °C, inhibitory activity remained above 50%. Circular dichroism analysis indicated that the protein is rich in loop structures and ß-conformations. Furthermore, in vivo assays against Helicoverpa armigera larvae were also performed with rTcTI in 0.1 mg mL-1 spray solutions on leaf surfaces, which reduced larval growth by 70% compared to the control treatment. Trials with cocoa plants infected with Mp showed a greater accumulation of TcTI in resistant varieties of T. cacao, so this regulation may be associated with different isoforms of TcTI. This inhibitor has biochemical characteristics suitable for biotechnological applications as well as in resistance studies of T. cacao and other crops.


Assuntos
Cacau/química , Cacau/parasitologia , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/farmacologia , Agaricales/efeitos dos fármacos , Agaricales/crescimento & desenvolvimento , Animais , Cacau/metabolismo , Estabilidade de Medicamentos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Isoformas de Proteínas , Temperatura , Inibidores da Tripsina/química , Inibidores da Tripsina/metabolismo
13.
Elife ; 112022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35044908

RESUMO

Predator-prey interactions influence prey traits through both consumptive and non-consumptive effects, and variation in these traits can shape vector-borne disease dynamics. Meta-analysis methods were employed to generate predation effect sizes by different categories of predators and mosquito prey. This analysis showed that multiple families of aquatic predators are effective in consumptively reducing mosquito survival, and that the survival of Aedes, Anopheles, and Culex mosquitoes is negatively impacted by consumptive effects of predators. Mosquito larval size was found to play a more important role in explaining the heterogeneity of consumptive effects from predators than mosquito genus. Mosquito survival and body size were reduced by non-consumptive effects of predators, but development time was not significantly impacted. In addition, Culex vectors demonstrated predator avoidance behavior during oviposition. The results of this meta-analysis suggest that predators limit disease transmission by reducing both vector survival and vector size, and that associations between drought and human West Nile virus cases could be driven by the vector behavior of predator avoidance during oviposition. These findings are likely to be useful to infectious disease modelers who rely on vector traits as predictors of transmission.


Mosquitoes are often referred to as the deadliest animals on earth because some species spread malaria, West Nile virus or other dangerous diseases when they bite humans and other animals. Adult mosquitoes fly to streams, ponds and other freshwater environments to lay their eggs. When the eggs hatch, the young mosquitoes live in the water until they are ready to grow wings and transform into adults. In the water, the young mosquitoes are particularly vulnerable to being eaten by dragonfly larvae, fish and other predators. When adult females are choosing where to lay their eggs, they can use their sense of smell to detect these predators and attempt to avoid them. Along with eating the mosquitoes, the predators may also reduce mosquito populations in other ways. For example, predators can disrupt feeding among young mosquitoes, which may affect the time that it takes for them to grow into adults or the size of their bodies once they reach the adult stage. Although the impacts of different predators have been tested separately in multiple settings, the overall effects of predators on the ability of mosquitoes to spread diseases to humans remain unclear. To address this question, Russell, Herzog et al. used an approach called meta-analysis on data from previous studies. The analysis found that along with increasing the death rates of mosquitoes, the presence of predators also leads to a reduction in the body size of those mosquitoes that survive, causing them to have shorter lifespans and fewer offspring. Russell, Herzog et al. found that one type of mosquito known as Culex ­ which carries West Nile virus ­ avoided laying its eggs near predators. During droughts, increased predation in streams, ponds and other aquatic environments may lead adult female Culex mosquitoes to lay their eggs closer to residential areas with fewer predators. Russell, Herzog et al. propose that this may be one reason why outbreaks of West Nile virus in humans are more likely to occur during droughts. In the future, these findings may help researchers to predict outbreaks of West Nile virus, malaria and other diseases carried by mosquitoes more accurately. Furthermore, the work of Russell, Herzog et al. provides examples of mosquito predators that could be used as biocontrol agents to decrease numbers of mosquitoes in certain regions.


Assuntos
Ambystomatidae , Culicidae/fisiologia , Transmissão de Doença Infecciosa , Peixes , Cadeia Alimentar , Insetos , Mosquitos Vetores/fisiologia , Animais , Tamanho Corporal , Culicidae/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Mosquitos Vetores/crescimento & desenvolvimento , Filogenia , Dinâmica Populacional
14.
Commun Biol ; 5(1): 66, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046515

RESUMO

Mathematical models that incorporate the temperature dependence of lab-measured life history traits are increasingly being used to predict how climatic warming will affect ectotherms, including disease vectors and other arthropods. These temperature-trait relationships are typically measured under laboratory conditions that ignore how conspecific competition in depleting resource environments-a commonly occurring scenario in nature-regulates natural populations. Here, we used laboratory experiments on the mosquito Aedes aegypti, combined with a stage-structured population model, to investigate this issue. We find that intensified larval competition in ecologically-realistic depleting resource environments can significantly diminish the vector's maximal population-level fitness across the entire temperature range, cause a ~6 °C decrease in the optimal temperature for fitness, and contract its thermal niche width by ~10 °C. Our results provide evidence for the importance of considering intra-specific competition under depleting resources when predicting how arthropod populations will respond to climatic warming.


Assuntos
Aedes/genética , Aptidão Genética , Temperatura , Aedes/crescimento & desenvolvimento , Animais , Larva/genética , Larva/crescimento & desenvolvimento , Mosquitos Vetores/genética , Mosquitos Vetores/crescimento & desenvolvimento
15.
Insect Biochem Mol Biol ; 141: 103718, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34982980

RESUMO

Chitin is an aminopolysaccharide present in insects as a major structural component of the cuticle. However, current knowledge on the chitin biosynthetic machinery, especially its constituents and mechanism, is limited. Using three independent binding assays, including co-immunoprecipitation, split-ubiquitin membrane yeast two-hybrid assay, and pull-down assay, we demonstrate that choline transporter-like protein 2 (Ctl2) interacts with krotzkopf verkehrt (kkv) in Drosophila melanogaster. The global knockdown of Ctl2 by RNA interference (RNAi) induced lethality at the larval stage. Tissue-specific RNAi to silence Ctl2 in the tracheal system and in the epidermis of the flies resulted in lethality at the first larval instar. The knockdown of Ctl2 in wings led to shrunken wings containing accumulated fluid. Calcofluor White staining demonstrated reduced chitin content in the first longitudinal vein of Ctl2 knockdown wings. The pro-cuticle, which was thinner compared to wildtype, exhibited a reduced number of chitin laminar layers. Phylogenetic analyses revealed orthologues of Ctl2 in different insect orders with highly conserved domains. Our findings provide new insights into cuticle formation, wherein Ctl2 plays an important role as a chitin-synthase interacting protein.


Assuntos
Quitina Sintase/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Membrana Transportadoras/genética , Asas de Animais/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Quitina Sintase/química , Quitina Sintase/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Epiderme/crescimento & desenvolvimento , Larva/genética , Larva/crescimento & desenvolvimento , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Alinhamento de Sequência
16.
Insect Biochem Mol Biol ; 141: 103719, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34999200

RESUMO

General odorant-binding proteins (GOBPs) are long considered responsible for the perception of plant odorants. In this study with the important noctuid pest Spodoptera litura, we functionally characterized that GOBP2 is also involved in the perception of sex pheromone components using in vivo CRISPR/Cas9 technique. First, the GOBP2 sgRNA and Cas9 protein were injected into the newly laid insect eggs, resulting in a 35.6% target mutagenesis in G0 moths. Then, the homozygous GOBP2 knockout strain (GOBP2-/-) was obtained after the screening of three generations. The knockout male and female moths displayed a significant reduction in EAG responses to the sex pheromone components, and the knockout females also displayed a significant reduction to plant odorants. In the behavioral assay of food choice, GOBP2-/- larvae lost the preference to artificial diet added with the major sex pheromone component Z9, E11-tetradecadienyl acetate (Z9, E11-14:Ac), whereas the WT larvae highly preferred the pheromone diet. Y-tube olfactometer assay and direct pheromone stimulation assay showed that GOBP2-/- male adults reduced significantly than WT males in percentages of choice, hair pencil displaying and mating attempt to Z9, E11-14:Ac. In the oviposition test, GOBP2-/- females showed significantly reduced preference for the soybean plants compared to the WT females. Our study demonstrated that GOBP2 plays an important role in perceiving sex pheromones in adult and larval stages, providing new insight into sex pheromone perception and a potential target for sex pheromone-based behavioral regulation in the pest.


Assuntos
Proteínas de Insetos/genética , Mariposas/genética , Receptores Odorantes/genética , Atrativos Sexuais/metabolismo , Animais , Sistemas CRISPR-Cas , Proteínas de Insetos/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Receptores Odorantes/metabolismo
17.
Elife ; 112022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35029145

RESUMO

The ability to restore lost body parts following traumatic injury is a fascinating area of biology that challenges current understanding of the ontogeny of differentiation. The origin of new cells needed to regenerate lost tissue, and whether they are pluripotent or have de- or trans-differentiated, remains one of the most important open questions . Additionally, it is not known whether developmental gene regulatory networks are reused or whether regeneration specific networks are deployed. Echinoderms, including sea stars, have extensive ability for regeneration, however, the technologies for obtaining transgenic echinoderms are limited and tracking cells involved in regeneration, and thus identifying the cellular sources and potencies has proven challenging. In this study, we develop new transgenic tools to follow the fate of populations of cells in the regenerating larva of the sea star Patiria miniata. We show that the larval serotonergic nervous system can regenerate following decapitation. Using a BAC-transgenesis approach we show that expression of the pan ectodermal marker, sox2, is induced in previously sox2 minus cells , even when cell division is inhibited. sox2+ cells give rise to new sox4+ neural precursors that then proceed along an embryonic neurogenesis pathway to reform the anterior nervous systems. sox2+ cells contribute to only neural and ectoderm lineages, indicating that these progenitors maintain their normal, embryonic lineage restriction. This indicates that sea star larval regeneration uses a combination of existing lineage restricted stem cells, as well as respecification of cells into neural lineages, and at least partial reuse of developmental GRNs to regenerate their nervous system.


Assuntos
Larva/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Regeneração , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Estrelas-do-Mar/fisiologia , Animais , Animais Geneticamente Modificados , Diferenciação Celular , Redes Reguladoras de Genes , Larva/crescimento & desenvolvimento , Neurogênese
18.
Elife ; 112022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35037619

RESUMO

Hedgehog (Hh) and Bone Morphogenetic Proteins (BMPs) pattern the developing Drosophila wing by functioning as short- and long-range morphogens, respectively. Here, we show that a previously unknown Hh-dependent mechanism fine-tunes the activity of BMPs. Through genome-wide expression profiling of the Drosophila wing imaginal discs, we identify nord as a novel target gene of the Hh signaling pathway. Nord is related to the vertebrate Neuron-Derived Neurotrophic Factor (NDNF) involved in congenital hypogonadotropic hypogonadism and several types of cancer. Loss- and gain-of-function analyses implicate Nord in the regulation of wing growth and proper crossvein patterning. At the molecular level, we present biochemical evidence that Nord is a secreted BMP-binding protein and localizes to the extracellular matrix. Nord binds to Decapentaplegic (Dpp) or the heterodimer Dpp-Glass-bottom boat (Gbb) to modulate their release and activity. Furthermore, we demonstrate that Nord is a dosage-dependent BMP modulator, where low levels of Nord promote and high levels inhibit BMP signaling. Taken together, we propose that Hh-induced Nord expression fine-tunes both the range and strength of BMP signaling in the developing Drosophila wing.


Assuntos
Padronização Corporal/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas Hedgehog/metabolismo , Asas de Animais/crescimento & desenvolvimento , Animais , Padronização Corporal/genética , Proteínas de Drosophila/genética , Proteínas Hedgehog/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo
19.
Nanotechnology ; 33(20)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35090149

RESUMO

In recent years, nanozymes based on two-dimensional (2D) nanomaterials have been receiving great interest for cancer photothermal therapy. 2D materials decorated with nanoparticles (NPs) on their surface are advantageous over conventional NPs and 2D material based systems because of their ability to synergistically improve the unique properties of both NPs and 2D materials. In this work, we report a nanozyme based on flower-like MoS2nanoflakes (NFs) by decorating their flower petals with NCeO2using polyethylenimine (PEI) as a linker molecule. A detailed investigation on toxicity, biocompatibility and degradation behavior of fabricated nanozymes in wild-typeDrosophila melanogastermodel revealed that there were no significant effects on the larval size, morphology, larval length, breadth and no time delay in changing larvae to the third instar stage at 7-10 d for MoS2NFs before and after NCeO2decoration. The muscle contraction and locomotion behavior of third instar larvae exhibited high distance coverage for NCeO2decorated MoS2NFs when compared to bare MoS2NFs and control groups. Notably, the MoS2and NCeO2-PEI-MoS2NFs treated groups at 100µg ml-1covered a distance of 38.2 mm (19.4% increase when compared with control) and 49.88 mm (no change when compared with control), respectively. High-resolution transmission electron microscopy investigations on the new born fly gut showed that the NCeO2decoration improved the degradation rate of MoS2NFs. Hence, nanozymes reported here have huge potential in various fields ranging from biosensing, cancer therapy and theranostics to tissue engineering and the treatment of Alzheimer's disease and retinal therapy.


Assuntos
Materiais Biocompatíveis/toxicidade , Cério/toxicidade , Dissulfetos/toxicidade , Molibdênio/toxicidade , Nanoestruturas/toxicidade , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Cério/administração & dosagem , Cério/química , Cério/farmacocinética , Dissulfetos/administração & dosagem , Dissulfetos/química , Dissulfetos/farmacocinética , Drosophila melanogaster , Trato Gastrointestinal/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Locomoção/efeitos dos fármacos , Teste de Materiais , Taxa de Depuração Metabólica , Molibdênio/administração & dosagem , Molibdênio/química , Molibdênio/farmacocinética , Contração Muscular/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Polietilenoimina/administração & dosagem , Polietilenoimina/química , Polietilenoimina/farmacocinética , Polietilenoimina/toxicidade , Espécies Reativas de Oxigênio/metabolismo
20.
Am J Physiol Renal Physiol ; 322(3): F280-F294, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35037468

RESUMO

There is an increasing interest in using zebrafish (Danio rerio) larva as a vertebrate screening model to study drug disposition. As the pronephric kidney of zebrafish larvae shares high similarity with the anatomy of nephrons in higher vertebrates including humans, we explored in this study whether 3- to 4-day-old zebrafish larvae have a fully functional pronephron. Intravenous injection of fluorescent polyethylene glycol and dextran derivatives of different molecular weight revealed a cutoff of 4.4-7.6 nm in hydrodynamic diameter for passive glomerular filtration, which is in agreement with corresponding values in rodents and humans. Distal tubular reabsorption of a FITC-folate conjugate, covalently modified with PEG2000, via folate receptor 1 was shown. Transport experiments of fluorescent substrates were assessed in the presence and absence of specific inhibitors in the blood systems. Thereby, functional expression in the proximal tubule of organic anion transporter oat (slc22) multidrug resistance-associated protein mrp1 (abcc1), mrp2 (abcc2), mrp4 (abcc4), and zebrafish larva p-glycoprotein analog abcb4 was shown. In addition, nonrenal clearance of fluorescent substrates and plasma protein binding characteristics were assessed in vivo. The results of transporter experiments were confirmed by extrapolation to ex vivo experiments in killifish (Fundulus heteroclitus) proximal kidney tubules. We conclude that the zebrafish larva has a fully functional pronephron at 96 h postfertilization and is therefore an attractive translational vertebrate screening model to bridge the gap between cell culture-based test systems and pharmacokinetic experiments in higher vertebrates.NEW & NOTEWORTHY The study of renal function remains a challenge. In vitro cell-based assays are approved to study, e.g., ABC/SLC-mediated drug transport but do not cover other renal functions such as glomerular filtration. Here, in vivo studies combined with in vitro assays are needed, which are time consuming and expensive. In view of these limitations, our proof-of-concept study demonstrates that the zebrafish larva is a translational in vivo test model that allows for mechanistic investigations to study renal function.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Néfrons/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Desenvolvimento Embrionário , Corantes Fluorescentes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas de Membrana Transportadoras/genética , Microscopia Confocal , /metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Néfrons/embriologia , Proteínas de Transporte de Cátions Orgânicos/genética , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Estudo de Prova de Conceito , Fatores de Tempo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
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