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1.
J Insect Sci ; 24(3)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717261

RESUMEN

The mealworm Tenebrio molitor L. (Coleoptera: Tenebrionidae) feeds on wheat bran and is considered both a pest and an edible insect. Its larvae contain proteins and essential amino acids, fats, and minerals, making them suitable for animal and human consumption. Zearalenone (ZEA) is the mycotoxin most commonly associated with Fusarium spp. It is found in cereals and cereal products, so their consumption is a major risk for mycotoxin contamination. One of the most important effects of ZEA is the induction of oxidative stress, which leads to physiological and behavioral changes. This study deals with the effects of high doses of ZEA (10 and 20 mg/kg) on survival, molting, growth, weight gain, activity of antioxidant enzymes superoxide dismutase (SOD) and glutathione S-transferase (GST), and locomotion of mealworm larvae. Both doses of ZEA were found to (i) have no effect on survival, (ii) increase molting frequency, SOD, and GST activity, and (iii) decrease body weight and locomotion, with more pronounced changes at 20 mg/kg. These results indicated the susceptibility of T. molitor larvae to high doses of ZEA in feed.


Asunto(s)
Glutatión Transferasa , Larva , Locomoción , Tenebrio , Zearalenona , Animales , Tenebrio/efectos de los fármacos , Tenebrio/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos , Zearalenona/toxicidad , Glutatión Transferasa/metabolismo , Locomoción/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Antioxidantes/metabolismo
2.
Environ Monit Assess ; 196(6): 531, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38724710

RESUMEN

The Samarco/Vale/BHP mine tailing dam breach that took place in Minas Gerais, southeastern Brazil, in 2015, deposited high concentrations of metals and metalloids in the Rio Doce basin, severely impacting freshwater and riverine forest ecosystems. To assess developmental instability of caddisflies in response to the environmental impacts of the dam breach, we investigated the fluctuating asymmetry (FA) in the species Smicridea (Rhyacophylax) coronata (Trichoptera: Hydropsychidae). FA was assessed at individual and populational scales using geometric morphometric methods in the cephalic capsule and mandibles of larvae and also on the forewings of adults, both collected under the impacted condition, and under the least disturbed condition. The levels of FA increased in response to stressors on the forewings at the populational scale, and on the mandibles, at individual scale. These morphological variations in the larval and adult stages may lead to detrimental effects and result in high mortality rates as well as lower adult fitness. Trichoptera forewings are revealed as suitable traits for assessing FA, holding potential for applications in biomonitoring programs. Directional asymmetry levels were higher than FA levels for all traits, and this correlation could be explained by a transition from fluctuating to directional asymmetry in the presence of heightened disturbance. Our results validate the relationship between the impacts from the dam breach and increased developmental instability in this species with likely cascade effects on the insect community.


Asunto(s)
Monitoreo del Ambiente , Larva , Minería , Animales , Larva/crecimiento & desarrollo , Insectos , Brasil , Contaminantes Químicos del Agua
3.
Invertebr Syst ; 382024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38744526

RESUMEN

Despite discovery more than 100years ago and documented global occurrence from shallow waters to the deep sea, the life cycle of the enigmatic crustacean y-larvae isincompletely understood and adult forms remain unknown. To date, only 2 of the 17 formally described species, all based on larval stages, have been investigated using an integrative taxonomic approach. This approach provided descriptions of the morphology of the naupliar and cyprid stages, and made use of exuvial voucher material and DNA barcodes. To improve our knowledge about the evolutionary history and ecological importance of y-larvae, we developed a novel protocol that maximises the amount of morpho-ecological and molecular data that can be harvested from single larval specimens. This includes single-specimen DNA barcoding and daily imaging of y-nauplii reared in culture dishes, mounting of the last naupliar exuviae on a slide as a reference voucher, live imaging of the y-cyprid instar that follows, and fixation, DNA extraction, amplification and sequencing of the y-cyprid specimen. Through development and testing of a suite of new primers for both nuclear and mitochondrial protein-coding and ribosomal genes, we showcase how new sequence data can be used to estimate the phylogeny of Facetotecta. We expect that our novel procedure will help to unravel the complex systematics of y-larvae and show how these fascinating larval forms have evolved. Moreover, we posit that our protocols should work on larval specimens from a diverse array of moulting marine invertebrate taxa.


Asunto(s)
Código de Barras del ADN Taxonómico , Larva , Animales , Código de Barras del ADN Taxonómico/métodos , Larva/genética , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Crustáceos/genética , Crustáceos/clasificación , Crustáceos/anatomía & histología , Especificidad de la Especie , Filogenia
4.
An Acad Bras Cienc ; 96(2): e20230671, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38747789

RESUMEN

Temperature affects the rate of biochemical and physiological processes in amphibians, influencing metamorphic traits. Temperature patterns, as those observed in latitudinal and altitudinal clines, may impose different challenges on amphibians depending on how species are geographically distributed. Moreover, species' response to environmental temperatures may also be phylogenetically constrained. Here, we explore the effects of acclimation to higher temperatures on tadpole survival, development, and growth, using a meta-analytical approach. We also evaluate whether the latitude and climatic variables at each collection site can explain differences in species' response to increasing temperature and whether these responses are phylogenetically conserved. Our results show that species that develop at relatively higher temperatures reach metamorphosis faster. Furthermore, absolute latitude at each collection site may partially explain heterogeneity in larval growth rate. Phylogenetic signal of traits in response to temperature indicates a non-random process in which related species resemble each other less than expected under Brownian motion evolution (BM) in all traits, except survival. The integration of studies in a meta-analytic framework allowed us to explore macroecological and macroevolutionary patterns and provided a better understanding of the effects of climate change on amphibians.


Asunto(s)
Anfibios , Evolución Biológica , Larva , Temperatura , Animales , Larva/crecimiento & desarrollo , Larva/fisiología , Anfibios/crecimiento & desarrollo , Anfibios/fisiología , Anfibios/clasificación , Cambio Climático , Filogenia , Metamorfosis Biológica/fisiología , Aclimatación/fisiología
5.
Parasitol Res ; 123(5): 211, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748261

RESUMEN

Ivermectin is one of the most widely used drugs for parasite control. Previous studies have shown a reduction in the abundance and diversity of "non-target" coprophilous organisms due to the presence of ivermectin (IVM) in bovine faecal matter (FM). Due to its breadth of behavioural habits, Calliphora vicina is a suitable dipteran species to evaluate the effects of IVM in FM. The aim of this work was to evaluate the effect of five concentrations of IVM in FM (3000, 300, 100, 30, and 3 ng/g) on the development of C. vicina. The following endpoints were evaluated: survival (between the first larval stage and emergence of new adults), larval development times to pupation and pupation times to adult, and adult emergence (% sex) and LC50. Sampling was performed from larval hatching at 60 and 120 min and at 3, 4, 5, and 12 h, and every 24 h specimens were weighed until pupae were observed. Data were analysed by ANOVA using a non-parametric Kruskal-Wallis test and as a function of elapsed development time and accumulated degree hours (ADH). Mortality at 3000 and 300 ng/g was 100% and 97%, respectively. There were statistically significant delays in adult emergence time (p = 0.0216) and in the ADH (p = 0.0431) between the control group (C) and 100 ng/g. The LC50 was determined at 5.6 ng/g. These results demonstrate the lethal and sub-lethal effects of IVM on C. vicina, while highlighting the usefulness of this species as a bioindicator for ecotoxicological studies.


Asunto(s)
Calliphoridae , Heces , Ivermectina , Larva , Animales , Ivermectina/farmacología , Calliphoridae/efectos de los fármacos , Calliphoridae/crecimiento & desarrollo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Heces/parasitología , Bovinos , Análisis de Supervivencia , Pupa/efectos de los fármacos , Pupa/crecimiento & desarrollo , Femenino , Antiparasitarios/farmacología , Masculino , Dosificación Letal Mediana , Dípteros/efectos de los fármacos , Dípteros/crecimiento & desarrollo
6.
Sci Data ; 11(1): 471, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724521

RESUMEN

We present a de novo transcriptome of the mosquito vector Culex pipiens, assembled by sequences of susceptible and insecticide resistant larvae. The high quality of the assembly was confirmed by TransRate and BUSCO. A mapping percentage until 94.8% was obtained by aligning contigs to Nr, SwissProt, and TrEMBL, with 27,281 sequences that simultaneously mapped on the three databases. A total of 14,966 ORFs were also functionally annotated by using the eggNOG database. Among them, we identified ORF sequences of the main gene families involved in insecticide resistance. Therefore, this resource stands as a valuable reference for further studies of differential gene expression as well as to identify genes of interest for genetic-based control tools.


Asunto(s)
Culex , Resistencia a los Insecticidas , Larva , Transcriptoma , Animales , Culex/genética , Larva/genética , Larva/crecimiento & desarrollo , Resistencia a los Insecticidas/genética , Mosquitos Vectores/genética , Sistemas de Lectura Abierta
7.
Arch Microbiol ; 206(6): 257, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734773

RESUMEN

There is a growing imperative for research into alternative compounds for the treatment of the fungal infections. Thus, many studies have focused on the analysis of antifungal proteins and peptides from different plant sources. Among these molecules are protease inhibitors (PIs). Previously, PIs present in the peptide-rich fractions called PEF1, PEF2 and PEF3 were identified from Capsicum chinense seeds, which have strong activity against phytopathogenic fungi. The aim of this study was to evaluate the mechanism of action and antimicrobial activity of PIs from PEF2 and PEF3 on the growth of yeasts of the genus Candida. In this work, analyses of their antimicrobial activity and cell viability were carried out. Subsequently, the mechanism of action by which the PIs cause the death of the yeasts was evaluated. Cytotoxicity was assessed in vitro by erythrocytes lysis and in vivo in Galleria mellonella larvae. PEF2 and PEF3 caused 100% of the growth inhibition of C. tropicalis and C. buinensis. For C. albicans inhibition was approximately 60% for both fractions. The PEF2 and PEF3 caused a reduction in mitochondrial functionality of 54% and 46% for C. albicans, 26% and 30% for C. tropicalis, and 71% and 68% for C. buinensis, respectively. These fractions induced morphological alterations, led to membrane permeabilization, elevated ROS levels, and resulted in necrotic cell death in C. tropicalis, whilst demonstrating low toxicity toward host cells. From the results obtained here, we intend to contribute to the understanding of the action of PIs in the control of fungal diseases of medical importance.


Asunto(s)
Antifúngicos , Candida , Inhibidores de Proteasas , Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida/crecimiento & desarrollo , Inhibidores de Proteasas/farmacología , Pruebas de Sensibilidad Microbiana , Animales , Capsicum/microbiología , Especies Reactivas de Oxígeno/metabolismo , Semillas/crecimiento & desarrollo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Eritrocitos/efectos de los fármacos , Larva/microbiología , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos
8.
J Agric Food Chem ; 72(19): 10828-10841, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691839

RESUMEN

Chemosensory proteins (CSPs) constitute a class of olfactory proteins localized in insect sensory organs that serve a crucial function in decoding external chemical stimuli. This study aims to elucidate the involvement of CrufCSP3 in olfactory perception within the context of Cotesia ruficrus, an indigenous endoparasitoid targeting the invasive pest Spodoptera frugiperda. Through fluorescence-competitive binding assays and site-directed mutagenesis, we pinpointed four amino acids as pivotal residues involved in the interaction between CrufCSP3 and five host-related compounds. Subsequent RNA interference experiments targeting CrufCSP3 unveiled a reduced sensitivity to specific host-related compounds and a decline in the parasitism rate of the FAW larvae. These findings unequivocally indicate the essential role of CrufCSP3 in the chemoreception process of C. ruficrus. Consequently, our study not only sheds light on the functional importance of CSPs in parasitic wasp behavior but also contributes to the development of eco-friendly and efficacious wasp behavior modifiers for effectively mitigating pest population surges.


Asunto(s)
Proteínas de Insectos , Spodoptera , Avispas , Animales , Avispas/química , Avispas/fisiología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/química , Larva/crecimiento & desarrollo , Interacciones Huésped-Parásitos , Percepción Olfatoria
9.
J Agric Food Chem ; 72(19): 10958-10969, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703118

RESUMEN

Demand for the exploration of botanical pesticides continues to increase due to the detrimental effects of synthetic chemicals on human health and the environment and the development of resistance by pests. Under the guidance of a bioactivity-guided approach and HSQC-based DeepSAT, 16 coumarin derivatives were discovered from the leaves of Ailanthus altissima (Mill.) Swingle, including seven undescribed monoterpenoid coumarins, three undescribed monoterpenoid phenylpropanoids, and two new coumarin derivatives. The structure and configurations of these compounds were established and validated via extensive spectroscopic analysis, acetonide analysis, and quantum chemical calculations. Biologically, 5 exhibited significant antifeedant activity toward the Plutella xylostella. Moreover, tyrosinase being closely related to the growth and development of larva, the inhibitory potentials of 5 against tyrosinase was evaluated in vitro and in silico. The bioactivity evaluation results highlight the prospect of 5 as a novel category of botanical insecticide.


Asunto(s)
Ailanthus , Cumarinas , Insecticidas , Extractos Vegetales , Hojas de la Planta , Hojas de la Planta/química , Animales , Cumarinas/farmacología , Cumarinas/química , Ailanthus/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Insecticidas/química , Insecticidas/farmacología , Estructura Molecular , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/crecimiento & desarrollo , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Bioensayo , Monoterpenos/farmacología , Monoterpenos/química , Conducta Alimentaria/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química
10.
J Agric Food Chem ; 72(19): 10794-10804, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38711396

RESUMEN

Chitin-degrading enzymes are critical components in regulating the molting process of the Asian corn borer and serve as potential targets for controlling this destructive pest of maize. Here, we used a scaffold-hopping strategy to design a series of efficient naphthylimide insecticides. Among them, compound 8c exhibited potent inhibition of chitinase from OfChi-h and OfChtI at low nanomolar concentrations (IC50 = 1.51 and 9.21 nM, respectively). Molecular docking simulations suggested that 8c binds to chitinase by mimicking the interaction of chitin oligosaccharide substrates with chitinase. At low ppm concentrations, compound 8c performed comparably to commercial insecticides in controlling the highly destructive plant pest, the Asian corn borer. Tests on a wide range of nontarget organisms indicate that compound 8c has very low toxicity. In addition, the effect of inhibitor treatment on the expression of genes associated with the Asian corn borer chitin-degrading enzymes was further investigated by quantitative real-time polymerase chain reaction. In conclusion, our study highlights the potential of 8c as a novel chitinase-targeting insecticide for effective control of the Asian corn borer, providing a promising solution in the quest for sustainable pest management.


Asunto(s)
Quitina , Quitinasas , Proteínas de Insectos , Insecticidas , Simulación del Acoplamiento Molecular , Mariposas Nocturnas , Zea mays , Animales , Quitinasas/química , Quitinasas/genética , Quitinasas/metabolismo , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/genética , Quitina/química , Quitina/metabolismo , Insecticidas/química , Insecticidas/farmacología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/química , Proteínas de Insectos/antagonistas & inhibidores , Zea mays/química , Zea mays/parasitología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Diseño de Fármacos , Control de Insectos , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos , Relación Estructura-Actividad
11.
J Agric Food Chem ; 72(19): 10805-10813, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712504

RESUMEN

Aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) mediate the responses of adaptive metabolism to various xenobiotics. Here, we found that BoAhR and BoARNT are highly expressed in the midgut of Bradysia odoriphaga larvae. The expression of BoAhR and BoARNT was significantly increased after exposure to imidacloprid and phoxim. The knockdown of BoAhR and BoARNT significantly decreased the expression of CYP6SX1 and CYP3828A1 as well as P450 enzyme activity and caused a significant increase in the sensitivity of larvae to imidacloprid and phoxim. Exposure to ß-naphthoflavone (BNF) significantly increased the expression of BoAhR, BoARNT, CYP6SX1, and CYP3828A1 as well as P450 activity and decreased larval sensitivity to imidacloprid and phoxim. Furthermore, CYP6SX1 and CYP3828A1 were significantly induced by imidacloprid and phoxim, and the silencing of these two genes significantly reduced larval tolerance to imidacloprid and phoxim. Taken together, the BoAhR/BoARNT pathway plays key roles in larval tolerance to imidacloprid and phoxim by regulating the expression of CYP6SX1 and CYP3828A1.


Asunto(s)
Proteínas de Insectos , Insecticidas , Larva , Neonicotinoides , Nitrocompuestos , Receptores de Hidrocarburo de Aril , Animales , Insecticidas/farmacología , Larva/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos , Nitrocompuestos/farmacología , Nitrocompuestos/metabolismo , Neonicotinoides/farmacología , Neonicotinoides/metabolismo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Receptores de Hidrocarburo de Aril/metabolismo , Receptores de Hidrocarburo de Aril/genética , Dípteros/metabolismo , Dípteros/genética , Dípteros/efectos de los fármacos , Dípteros/crecimiento & desarrollo , Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Inactivación Metabólica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
12.
Glob Chang Biol ; 30(5): e17294, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38738554

RESUMEN

The potential for climate change to disrupt phenology-mediated interactions in interaction networks has attracted considerable attention in recent decades. Frequently, studies emphasize the fragility of ephemeral seasonal interactions, and the risks posed by phenological asynchrony. Here, we argue that the fitness consequences of asynchrony in phenological interactions may often be more buffered than is typically acknowledged. We identify three main forms that buffering may take: (i) mechanisms that reduce asynchrony between consumer and resource; (ii) mechanisms that reduce the costs of being asynchronous; and (iii) mechanisms that dampen interannual variance in performance across higher organizational units. Using synchrony between the hatching of winter moth caterpillars and the leafing of their host-plants as a case study, we identify a wide variety of buffers that reduce the detrimental consequences of phenological asynchrony on caterpillar individuals, populations, and meta-populations. We follow this by drawing on examples across a breadth of taxa, and demonstrate that these buffering mechanisms may be quite general. We conclude by identifying key gaps in our knowledge of the fitness and demographic consequences of buffering, in the context of phenological mismatch. Buffering has the potential to substantially alter our understanding of the biotic impacts of future climate change-a greater recognition of the contribution of these mechanisms may reveal that many trophic interactions are surprisingly resilient, and also serve to shift research emphasis to those systems with fewer buffers and towards identifying the limits of those buffers.


Asunto(s)
Cambio Climático , Mariposas Nocturnas , Animales , Larva/fisiología , Larva/crecimiento & desarrollo , Mariposas Nocturnas/fisiología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Estaciones del Año
13.
Cell Mol Life Sci ; 81(1): 213, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727814

RESUMEN

Trimeric G proteins transduce signals from a superfamily of receptors and each G protein controls a wide range of cellular and systemic functions. Their highly conserved alpha subunits fall in five classes, four of which have been well investigated (Gs, Gi, G12, Gq). In contrast, the function of the fifth class, Gv is completely unknown, despite its broad occurrence and evolutionary ancient origin (older than metazoans). Here we show a dynamic presence of Gv mRNA in several organs during early development of zebrafish, including the hatching gland, the pronephros and several cartilage anlagen, employing in situ hybridisation. Next, we generated a Gv frameshift mutation in zebrafish and observed distinct phenotypes such as reduced oviposition, premature hatching and craniofacial abnormalities in bone and cartilage of larval zebrafish. These phenotypes could suggest a disturbance in ionic homeostasis as a common denominator. Indeed, we find reduced levels of calcium, magnesium and potassium in the larvae and changes in expression levels of the sodium potassium pump atp1a1a.5 and the sodium/calcium exchanger ncx1b in larvae and in the adult kidney, a major osmoregulatory organ. Additionally, expression of sodium chloride cotransporter slc12a3 and the anion exchanger slc26a4 is altered in complementary ways in adult kidney. It appears that Gv may modulate ionic homeostasis in zebrafish during development and in adults. Our results constitute the first insight into the function of the fifth class of G alpha proteins.


Asunto(s)
Homeostasis , Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/metabolismo , Homeostasis/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Subunidades alfa de la Proteína de Unión al GTP/genética , Larva/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , Calcio/metabolismo , Riñón/metabolismo , Magnesio/metabolismo
14.
Malar J ; 23(1): 158, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773512

RESUMEN

BACKGROUND: This study aimed to assess the spatial distribution of Anopheles mosquito larval habitats and the environmental factors associated with them, as a prerequisite for the implementation of larviciding. METHODS: The study was conducted in December 2021, during the transition period between the end of the short rainy season (September-November) and the short dry season (December-February). Physical, biological, and land cover data were integrated with entomological observations to collect Anopheles larvae in three major towns: Mitzic, Oyem, and Bitam, using the "dipping" method during the transition from rainy to dry season. The collected larvae were then reared in a field laboratory established for the study period. After the Anopheles mosquitoes had emerged, their species were identified using appropriate morphological taxonomic keys. To determine the influence of environmental factors on the breeding of Anopheles mosquitoes, multiple-factor analysis (MFA) and a binomial generalized linear model were used. RESULTS: According to the study, only 33.1% out of the 284 larval habitats examined were found to be positive for Anopheles larvae, which were primarily identified as belonging to the Anopheles gambiae complex. The findings of the research suggested that the presence of An. gambiae complex larvae in larval habitats was associated with various significant factors such as higher urbanization, the size and type of the larval habitats (pools and puddles), co-occurrence with Culex and Aedes larvae, hot spots in ambient temperature, moderate rainfall, and land use patterns. CONCLUSIONS: The results of this research mark the initiation of a focused vector control plan that aims to eradicate or lessen the larval habitats of An. gambiae mosquitoes in Gabon's Woleu Ntem province. This approach deals with the root causes of malaria transmission through larvae and is consistent with the World Health Organization's (WHO) worldwide objective to decrease malaria prevalence in regions where it is endemic.


Asunto(s)
Anopheles , Ecosistema , Larva , Malaria , Mosquitos Vectores , Animales , Anopheles/fisiología , Anopheles/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/fisiología , Gabón , Malaria/transmisión , Mosquitos Vectores/fisiología , Estaciones del Año , Análisis Espacial , Distribución Animal
15.
J Agric Food Chem ; 72(20): 11381-11391, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38728113

RESUMEN

RNA interference (RNAi)-based biopesticides offer an attractive avenue for pest control. Previous studies revealed high RNAi sensitivity in Holotrichia parallela larvae, showcasing its potential for grub control. In this study, we aimed to develop an environmentally friendly RNAi method for H. parallela larvae. The double-stranded RNA (dsRNA) of the V-ATPase-a gene (HpVAA) was loaded onto layered double hydroxide (LDH). The dsRNA/LDH nanocomplex exhibited increased environmental stability, and we investigated the absorption rate and permeability of dsRNA-nanoparticle complexes and explored the RNAi controlling effect. Silencing the HpVAA gene was found to darken the epidermis of H. parallela larvae, with growth cessation or death or mortality, disrupting the epidermis and midgut structure. Quantitative reverse transcription-polymerase chain reaction and confocal microscopy confirmed the effective absorption of the dsRNA/LDH nanocomplex by peanut plants, with distribution in roots, stems, and leaves. Nanomaterial-mediated RNAi silenced the target genes, leading to the death of pests. Therefore, these findings indicate the successful application of the nanomaterial-mediated RNAi system for underground pests, thus establishing a theoretical foundation for developing a green, safe, and efficient pest control strategy.


Asunto(s)
Larva , Interferencia de ARN , ARN Bicatenario , Animales , Larva/crecimiento & desarrollo , Larva/genética , ARN Bicatenario/genética , ARN Bicatenario/metabolismo , Hidróxidos/química , Hidróxidos/metabolismo , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo , ATPasas de Translocación de Protón Vacuolares/química , Arachis/genética , Arachis/química , Arachis/crecimiento & desarrollo , Arachis/metabolismo , Control Biológico de Vectores , Escarabajos/genética , Escarabajos/crecimiento & desarrollo , Tecnología Química Verde , Agentes de Control Biológico/química , Agentes de Control Biológico/metabolismo , Nanopartículas/química
16.
Fly (Austin) ; 18(1): 2352938, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38741287

RESUMEN

To identify genes required for brain growth, we took an RNAi knockdown reverse genetic approach in Drosophila. One potential candidate isolated from this effort is the anti-lipogenic gene adipose (adp). Adp has an established role in the negative regulation of lipogenesis in the fat body of the fly and adipose tissue in mammals. While fat is key to proper development in general, adp has not been investigated during brain development. Here, we found that RNAi knockdown of adp in neuronal stem cells and neurons results in reduced brain lobe volume and sought to replicate this with a mutant fly. We generated a novel adp mutant that acts as a loss-of-function mutant based on buoyancy assay results. We found that despite a change in fat content in the body overall and a decrease in the number of larger (>5 µm) brain lipid droplets, there was no change in the brain lobe volume of mutant larvae. Overall, our work describes a novel adp mutant that can functionally replace the long-standing adp60 mutant and shows that the adp gene has no obvious involvement in brain growth.


Asunto(s)
Encéfalo , Proteínas de Drosophila , Animales , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Encéfalo/metabolismo , Encéfalo/crecimiento & desarrollo , Drosophila melanogaster/genética , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/metabolismo , Mutación con Pérdida de Función , Interferencia de ARN , Neuronas/metabolismo , Larva/crecimiento & desarrollo , Larva/genética , Larva/metabolismo , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Drosophila/genética , Drosophila/metabolismo , Drosophila/crecimiento & desarrollo , Tejido Adiposo/metabolismo , Mutación
17.
Commun Biol ; 7(1): 521, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702540

RESUMEN

Histone acetylation, a crucial epigenetic modification, is governed by histone acetyltransferases (HATs), that regulate many biological processes. Functions of HATs in insects are not well understood. We identified 27 HATs and determined their functions using RNA interference (RNAi) in the model insect, Tribolium castaneum. Among HATs studied, N-alpha-acetyltransferase 40 (NAA40) knockdown caused a severe phenotype of arrested larval development. The steroid hormone, ecdysone induced NAA40 expression through its receptor, EcR (ecdysone receptor). Interestingly, ecdysone-induced NAA40 regulates EcR expression. NAA40 acetylates histone H4 protein, associated with the promoters of ecdysone response genes: EcR, E74, E75, and HR3, and causes an increase in their expression. In the absence of ecdysone and NAA40, histone H4 methylation by arginine methyltransferase 1 (ART1) suppressed the above genes. However, elevated ecdysone levels at the end of the larval period induced NAA40, promoting histone H4 acetylation and increasing the expression of ecdysone response genes. NAA40 is also required for EcR, and steroid-receptor co-activator (SRC) mediated induction of E74, E75, and HR3. These findings highlight the key role of ecdysone-induced NAA40-mediated histone acetylation in the regulation of metamorphosis.


Asunto(s)
Ecdisona , Histona Acetiltransferasas , Histonas , Metamorfosis Biológica , Receptores de Esteroides , Tribolium , Animales , Tribolium/genética , Tribolium/crecimiento & desarrollo , Tribolium/metabolismo , Tribolium/enzimología , Histonas/metabolismo , Ecdisona/metabolismo , Acetilación , Metamorfosis Biológica/genética , Histona Acetiltransferasas/metabolismo , Histona Acetiltransferasas/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Larva/crecimiento & desarrollo , Larva/genética , Larva/metabolismo , Interferencia de ARN
18.
Chemosphere ; 358: 142207, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697560

RESUMEN

Fenazaquin, a potent insecticide widely used to control phytophagous mites, has recently emerged as a potential solution for managing Varroa destructor mites in honeybees. However, the comprehensive impact of fenazaquin on honeybee health remains insufficiently understood. Our current study investigated the acute and chronic toxicity of fenazaquin to honeybee larvae, along with its influence on larval hemolymph metabolism and gut microbiota. Results showed that the acute median lethal dose (LD50) of fenazaquin for honeybee larvae was 1.786 µg/larva, and the chronic LD50 was 1.213 µg/larva. Although chronic exposure to low doses of fenazaquin exhibited no significant effect on larval development, increasing doses of fenazaquin resulted in significant increases in larval mortality, developmental time, and deformity rates. At the metabolic level, high doses of fenazaquin inhibited nucleotide, purine, and lipid metabolism pathways in the larval hemolymph, leading to energy metabolism disorders and physiological dysfunction. Furthermore, high doses of fenazaquin reduced gut microbial diversity and abundance, characterized by decreased relative abundance of functional gut bacterium Lactobacillus kunkeei and increased pathogenic bacterium Melissococcus plutonius. The disrupted gut microbiota, combined with the observed gut tissue damage, could potentially impair food digestion and nutrient absorption in the larvae. Our results provide valuable insights into the complex and diverse effects of fenazaquin on honeybee larvae, establishing an important theoretical basis for applying fenazaquin in beekeeping.


Asunto(s)
Acaricidas , Microbioma Gastrointestinal , Hemolinfa , Larva , Metaboloma , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Abejas/efectos de los fármacos , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Hemolinfa/metabolismo , Hemolinfa/efectos de los fármacos , Metaboloma/efectos de los fármacos , Acaricidas/toxicidad
19.
Chemosphere ; 358: 142162, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697568

RESUMEN

This study investigates the combined impact of microplastics (MP) and Chlorpyriphos (CPF) on sea urchin larvae (Paracentrotus lividus) under the backdrop of ocean warming and acidification. While the individual toxic effects of these pollutants have been previously reported, their combined effects remain poorly understood. Two experiments were conducted using different concentrations of CPF (EC10 and EC50) based on previous studies from our group. MP were adsorbed in CPF to simulate realistic environmental conditions. Additionally, water acidification and warming protocols were implemented to mimic future ocean conditions. Sea urchin embryo toxicity tests were conducted to assess larval development under various treatment combinations of CPF, MP, ocean acidification (OA), and temperature (OW). Morphometric measurements and biochemical analyses were performed to evaluate the effects comprehensively. Results indicate that combined stressors lead to significant morphological alterations, such as increased larval width and reduced stomach volume. Furthermore, biochemical biomarkers like acetylcholinesterase (AChE), glutathione S-transferase (GST), and glutathione reductase (GRx) activities were affected, indicating oxidative stress and impaired detoxification capacity. Interestingly, while temperature increase was expected to enhance larval growth, it instead induced thermal stress, resulting in lower growth rates. This underscores the importance of considering multiple stressors in ecological assessments. Biochemical biomarkers provided early indications of stress responses, complementing traditional growth measurements. The study highlights the necessity of holistic approaches when assessing environmental impacts on marine ecosystems. Understanding interactions between pollutants and environmental stressors is crucial for effective conservation strategies. Future research should delve deeper into the impacts at lower biological levels and explore adaptive mechanisms in marine organisms facing multiple stressors. By doing so, we can better anticipate and mitigate the adverse effects of anthropogenic pollutants on marine biodiversity and ecosystem health.


Asunto(s)
Biomarcadores , Cambio Climático , Larva , Paracentrotus , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/toxicidad , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Biomarcadores/metabolismo , Paracentrotus/efectos de los fármacos , Glutatión Transferasa/metabolismo , Microplásticos/toxicidad , Acetilcolinesterasa/metabolismo , Estrés Oxidativo/efectos de los fármacos , Agua de Mar/química , Glutatión Reductasa/metabolismo
20.
PLoS One ; 19(5): e0299154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38709802

RESUMEN

The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32°C. The development time for eggs, larvae, and pupae varied from 0-3 days, 10-18 days, and 7-16 days, respectively. The optimal temperature range for immature stage survival and female fecundity was identified as 21-25°C, with the intrinsic rate of increase (rm) and gross reproductive rate (GRR) peaking at 25-28°C. Model validation confirmed the accuracy of these findings. The research further projected the Establishment Risk Index (ERI), Activity Index (AI), and Generation Index (GI) for FAW under current and future climates (2050 and 2070) using RCP 2.6 and RCP 8.5 scenarios. Results indicate that RCP 2.6 leads to a reduction in high-risk FAW areas, particularly in central Africa. Conversely, RCP 8.5 suggests an increase in areas conducive to FAW activity. These findings highlight the impact of climate policy on pest dynamics and the importance of incorporating climatic factors into pest management strategies. The study predicts a potential decrease in FAW prevalence in West Africa by 2070 under aggressive climate mitigation, providing a basis for future FAW management approaches.


Asunto(s)
Estadios del Ciclo de Vida , Spodoptera , Temperatura , Zea mays , Animales , Spodoptera/fisiología , Spodoptera/crecimiento & desarrollo , África , Zea mays/parasitología , Zea mays/crecimiento & desarrollo , Tablas de Vida , Femenino , Larva/fisiología , Larva/crecimiento & desarrollo
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