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1.
Nature ; 584(7822): 584-588, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32788724

RESUMO

Locust plagues threaten agricultural and environmental safety throughout the world1,2. Aggregation pheromones have a crucial role in the transition of locusts from a solitary form to the devastating gregarious form and the formation of large-scale swarms3,4. However, none of the candidate compounds reported5-7 meet all the criteria for a locust aggregation pheromone. Here, using behavioural assays, electrophysiological recording, olfactory receptor characterization and field experiments, we demonstrate that 4-vinylanisole (4VA) (also known as 4-methoxystyrene) is an aggregation pheromone of the migratory locust (Locusta migratoria). Both gregarious and solitary locusts are strongly attracted to 4VA, regardless of age and sex. Although it is emitted specifically by gregarious locusts, 4VA production can be triggered by aggregation of four to five solitary locusts. It elicits responses specifically from basiconic sensilla on locust antennae. We also identified OR35 as a specific olfactory receptor of 4VA. Knockout of OR35 using CRISPR-Cas9 markedly reduced the electrophysiological responses of the antennae and impaired 4VA behavioural attractiveness. Finally, field trapping experiments verified the attractiveness of 4VA to experimental and wild populations. These findings identify a locust aggregation pheromone and provide insights for the development of novel control strategies for locusts.


Assuntos
Locusta migratoria/efeitos dos fármacos , Locusta migratoria/fisiologia , Feromônios/metabolismo , Feromônios/farmacologia , Estirenos/metabolismo , Estirenos/farmacologia , Envelhecimento , Migração Animal/efeitos dos fármacos , Animais , Ecossistema , Feminino , Controle de Insetos , Locusta migratoria/química , Masculino , Densidade Demográfica , Receptores Odorantes/deficiência , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Sensilas/fisiologia
2.
Proc Natl Acad Sci U S A ; 120(37): e2306659120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669362

RESUMO

Chemical signals from conspecifics are essential in insect group formation and maintenance. Migratory locusts use the aggregation pheromone 4-vinylanisole (4VA), specifically released by gregarious locusts, to attract and recruit conspecific individuals, leading to the formation of large-scale swarms. However, how 4VA contributes to the transition from solitary phase to gregarious phase remains unclear. We investigated the occurrence of locust behavioral phase changes in the presence and absence of 4VA perception. The findings indicated that solitary locusts require crowding for 48 and 72 h to adopt partial and analogous gregarious behavior. However, exposure to increased concentrations of 4VA enabled solitary locusts to display behavioral changes within 24 h of crowding. Crowded solitary locusts with RNAi knockdown of Or35, the specific olfactory receptor for 4VA, failed to exhibit gregarious behaviors. Conversely, the knockdown of Or35 in gregarious locusts resulted in the appearance of solitary behavior. Additionally, a multi-individual behavioral assay system was developed to evaluate the interactions among locust individuals, and four behavioral parameters representing the inclination and conduct of social interactions were positively correlated with the process of crowding. Our data indicated that exposure to 4VA accelerated the behavioral transition from solitary phase to gregarious phase by enhancing the propensity toward proximity and body contact among conspecific individuals. These results highlight the crucial roles of 4VA in the behavioral phase transition of locusts. Furthermore, this study offers valuable insights into the mechanisms of behavioral plasticity that promote the formation of locust swarms and suggests the potential for 4VA application in locust control.


Assuntos
Gafanhotos , Gafanhotos/fisiologia , Comunicação Animal , Comportamento Animal , Receptores Odorantes/metabolismo , Estirenos/metabolismo
3.
Am J Pathol ; 194(1): 101-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37827215

RESUMO

The Wnt/ß-catenin pathway represents a promising therapeutic target for mitigating kidney fibrosis. Corin possesses the homologous ligand binding site [Frizzled-cysteine-rich domain (Fz-CRD)] similar to Frizzled proteins, which act as receptors for Wnt. The Fz-CRD has been found in eight different proteins, all of which, except for corin, are known to bind Wnt and regulate its signal transmission. We hypothesized that corin may inhibit the Wnt/ß-catenin signaling pathway and thereby reduce fibrogenesis. Reduced expression of corin along with the increased activity of Wnt/ß-catenin signaling was found in unilateral ureteral obstruction (UUO) and ureteral ischemia/reperfusion injury (UIRI) models. In vitro, corin bound to the Wnt1 through its Fz-CRDs and inhibit the Wnt1 function responsible for activating ß-catenin. Transforming growth factor-ß1 inhibited corin expression, accompanied by activation of ß-catenin; conversely, overexpression of corin attenuated the fibrotic effects of transforming growth factor-ß1. In vivo, adenovirus-mediated overexpression of corin attenuated the progression of fibrosis, which was potentially associated with the inhibition of Wnt/ß-catenin signaling and the down-regulation of its target genes after UUO and UIRI. These results suggest that corin acts as an antagonist that protects the kidney from pathogenic Wnt/ß-catenin signaling and from fibrosis following UUO and UIRI.


Assuntos
Nefropatias , Via de Sinalização Wnt , Camundongos , Animais , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Nefropatias/genética , Nefropatias/prevenção & controle , Nefropatias/metabolismo , Rim/patologia , Fibrose , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
4.
Kidney Blood Press Res ; 49(1): 345-354, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38615671

RESUMO

INTRODUCTION: This study evaluated the phenotypic and pathology characteristics of patients undergoing kidney biopsy at a single center, while also determining the frequency and factors associated with clinical outcomes. METHODS: The incidence and distribution of biopsy-proven kidney diseases in 2000-2019 were surveyed. Consecutive individuals diagnosed with membranous nephropathy (MN), immunoglobulin A nephropathy (IgAN), and minimal change disease (MCD) between August 2015 and December 2019 were enrolled in the prospective 2-year follow-up study. Outcomes included remission of proteinuria and kidney disease progression events. Multivariable-adjusted Cox proportional hazards model was applied. RESULTS: 4,550 kidney biopsies were performed in 2000-2019, showing a noticeable increase in the proportion of MN. 426 patients were enrolled in the follow-up cohort. 346 (81.2%) achieved remission of proteinuria, 39 (9.2%) suffered kidney disease progression and 51.3% of them were diagnosed with IgAN. Kidney pathological diagnosis (MN vs. MCD: hazard ratio [HR], 0.42; 95% confidence interval [95% CI], 0.31-0.57; IgAN vs. MCD: 0.58; 0.39-0.85), levels of 24-h urine protein at biopsy (1.04; 1.00-1.08) and presence of nodular mesangial sclerosis (0.70; 0.49-0.99) were significantly correlated with remission of proteinuria after adjusting for baseline variables. 24-h urine protein levels at biopsy (1.14; 1.04-1.25) and the presence of crescents (2.30; 1.06-4.95) were the independent risk factors for kidney disease progression events after adjusting for baseline variables. CONCLUSION: The increasing frequency of MN has been affirmed over the past 2 decades. The therapeutic status, clinical outcomes, and factors influencing these outcomes were presented in this single-center study for the three primary glomerular diseases.


Assuntos
Progressão da Doença , Glomerulonefrite por IGA , Glomerulonefrite Membranosa , Rim , Nefrose Lipoide , Humanos , Glomerulonefrite Membranosa/patologia , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/diagnóstico , Nefrose Lipoide/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Biópsia , Rim/patologia , Estudos Prospectivos , Seguimentos , Proteinúria/etiologia
5.
Nanotechnology ; 35(4)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37669634

RESUMO

Two-dimensional transition metal dichalcogenides (TMDs), as flexible and stretchable materials, have attracted considerable attention in the field of novel flexible electronics due to their excellent mechanical, optical, and electronic properties. Among the various TMD materials, atomically thin MoS2has become the most widely used material due to its advantageous properties, such as its adjustable bandgap, excellent performance, and ease of preparation. In this work, we demonstrated the practicality of a stacked wafer-scale two-layer MoS2film obtained by transferring multiple single-layer films grown using chemical vapor deposition. The MoS2field-effect transistor cell had a top-gated device structure with a (PI) film as the substrate, which exhibited a high on/off ratio (108), large average mobility (∼8.56 cm2V-1s-1), and exceptional uniformity. Furthermore, a range of flexible integrated logic devices, including inverters, NOR gates, and NAND gates, were successfully implemented via traditional lithography. These results highlight the immense potential of TMD materials, particularly MoS2, in enabling advanced flexible electronic and optoelectronic devices, which pave the way for transformative applications in future-generation electronics.

6.
Small ; 18(20): e2107650, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35435320

RESUMO

Two-dimentional semiconductors have shown potential applications in multi-bridge channel field-effect transistors (MBC-FETs) and complementary field-effect transistors (C-FETs) due to their atomic thickness, stackability, and excellent electrical properties. However, the exploration of MBC-FET and C-FET based on large-scale 2D semiconductors is still lacking. Here, based on a reliable vertical stacking of wafer-scale 2D semiconductors, large-scale MBC-FETs and C-FETs using n-type MoS2 and p-type MoTe2 are successfully fabricated. The drive current of an MBC-FET with two layers of MoS2 channel (20 µm/10 µm) is up to 60 µA under 1 V bias. Compared with the single-gate MoS2 FET, the carrier mobility of MBC-FET is 2.3 times higher and the sub-threshold swing is 70% smaller. Furthermore, NAND and NOR logic circuits are also constructed based on two vertically stacked MoS2 channels. Then, C-FET arrays are fabricated by 3D integrating n-type MoS2 FET and p-type MoTe2 FET, which exhibit a voltage gain of 7 V/V when VDD  = 4 V. In addition, this C-FET device can directly convert light signals to an electrical digital signal within a single device. The demonstration of MBC-FET and C-FET based on large-scale 2D semiconductors will promote the application of 2D semiconductors in next-generation circuits.

7.
Food Microbiol ; 108: 104096, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36088112

RESUMO

Microbes in pit mud play key roles in fermentation cellars for Chinese strong-flavor Baijiu (SFB) production. Pit mud, however, is frequently degraded during production, compromising the quality of the end product. In this study, a bioremediation method was used to restore degraded pit mud (DPM) using indigenous microbes derived from SFB production. Metabolomics and metagenomics were used to determine the dynamics of prokaryotes during DPM restoration and their link to SFB production. The composition of flavor compounds in SFB changed (P = 0.0001) before and after restoration of DPM. Consistent with the improved sensory quality, the ethyl caproate/ethyl lactate ratio, an SFB quality measure, increased after restoration (P < 0.001). The concentrations of humus, NH4+, available phosphorus, and available potassium in DPM increased during the restoration process (P < 0.05), which is consistent with high-quality pit mud. The relative abundance of microbes that are beneficial to SFB fermentation, such as Caproiciproducens, a bacterium that produces caproic acid, increased during the restoration process. Furthermore, a total of 18 metabolic pathways were enriched (P < 0.05) from DPM before and after restoration. This includes butanoate metabolism and pyruvate metabolism, which are related to the synthesis of key flavor esters in SFB.


Assuntos
Bebidas Alcoólicas , Bactérias , Bebidas Alcoólicas/microbiologia , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Fermentação
8.
Ren Fail ; 44(1): 116-125, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35172688

RESUMO

BACKGROUND: Although thunder god vine (Tripterygium wilfordii) has been widely used for treatment of idiopathic membranous nephropathy (IMN), the pharmacological mechanisms underlying its effects are still unclear. This study investigated potential therapeutic targets and the pharmacological mechanism of T. wilfordii for the treatment of IMN based on network pharmacology. METHODS: Active components of T. wilfordii were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. IMN-associated target genes were collected from the GeneCards, DisGeNET, and OMIM databases. VENNY 2.1 was used to identify the overlapping genes between active compounds of T. wilfordii and IMN target genes. The STRING database and Cytoscape 3.7.2 software were used to analyze interactions among overlapping genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the targets were performed using Rx64 4.0.2 software, colorspace, stringi, DOSE, clusterProfiler, and enrichplot packages. RESULTS: A total of 153 compound-related genes and 1485 IMN-related genes were obtained, and 45 core genes that overlapped between both categories were identified. The protein-protein interaction network and MCODE results indicated that the targets TP53, MAPK8, MAPK14, STAT3, IFNG, ICAM1, IL4, TGFB1, PPARG, and MMP1 play important roles in the treatment of T. wilfordii on IMN. Enrichment analysis showed that the main pathways of targets were the AGE signaling pathway, IL-17 signaling pathway, TNF signaling pathway, and Toll-like receptor signaling pathway. CONCLUSION: This study revealed potential multi-component and multi-target mechanisms of T. wilfordii for the treatment of IMN based on network pharmacological, and provided a scientific basis for further experimental studies.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Glomerulonefrite Membranosa/tratamento farmacológico , Tripterygium/química , Bases de Dados Genéticas , Bases de Dados de Produtos Farmacêuticos , Glomerulonefrite Membranosa/metabolismo , Glomerulonefrite Membranosa/patologia , Humanos , Farmacologia em Rede/métodos , Mapas de Interação de Proteínas/efeitos dos fármacos , Transdução de Sinais
9.
FASEB J ; 34(1): 513-524, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914587

RESUMO

Translocator protein (TSPO, 18kDa), which was previously known as a peripheral-type benzodiazepine receptor, is associated with psychiatric disorders and acts as a neuroimaging biomarker. However, its function and mechanism in modulating behaviors are less well-known. Herein, we found that TSPO in migratory locusts shows conserved protein traits and is expressed at high levels in the brains. The expression levels of tspo mRNA and protein were higher in brains of solitary locusts than those in gregarious locusts, whereas the mRNA and protein expression levels remained stable during crowding and isolation, suggesting that the expression level of TSPO is potentially associated with behavioral phenotype of solitary locusts. Moreover, tspo RNAi knockdown in the brains of solitary locusts decreased their olfactory repulsion. After RNAi knockdown of tyramine receptor (TyR) in the brains of solitary locusts, RNA-seq analysis identified that a functional class of receptors, which included tspo, was downregulated significantly. Moreover, tspo mRNA and protein expression levels were downregulated and upregulated after TyR RNAi knockdown and activation, respectively. tspo RNAi knockdown in the brains of solitary locusts induced the attractive response and inhibited the function of tyramine (TA)-TyR in inducing olfactory repulsion. In gregarious locusts, tspo RNAi knockdown inhibited the function of TA-TyR inducing olfactory repulsion. This study confirms that TSPO acts as a crucial effector protein in TA-TyR signaling to modulate olfactory repulsion. Furthermore, this study provides a novel mechanism by which TSPO functionally connects a G-protein-coupled receptor and a mitochondria membrane protein in modulating olfactory repulsion.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/fisiologia , Gafanhotos/fisiologia , Receptores de Amina Biogênica/metabolismo , Receptores de GABA/metabolismo , Olfato/fisiologia , Animais , Feminino , Masculino , Receptores de Amina Biogênica/genética , Receptores de GABA/genética , Transdução de Sinais
10.
Inorg Chem ; 60(20): 15390-15403, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34592815

RESUMO

The heterojunction constructed by tungsten oxide and zinc oxide materials can improve the problem of easy deactivation of electrons, which is a new and effective strategy for realizing anticorrosion. Here, the ZnO/WO2.92 heterojunction modified by oxygen vacancies (OVs) serving as the photoelectric conversion center was not consumed to provide continuous light-induced protection for steel, and the impedance value was increased by 185.35% compared to that of epoxy resin after 72 h of corrosion. The enhanced anticorrosion activity was due to OV modification leading to oxygen adsorption and electron capture, which inhibited the cathodic corrosion reaction and effectively hindered electron transport. Additionally, the localized surface plasmon resonance effect produced by OVs improved light utilization efficiency and increased electron density, which enabled numerous photoelectrons to gather on the surface of the iron substrate to reduce the corrosion rate of metals. Besides, the cascade effect of the ZnO/WO2.92 heterojunction promoted the transfer of e-/h+ to form an electric field that allowed the directional flow of electrons to inhibit the anode dissolution process. Thus, exploring the corrosion reaction involving OVs and heterojunction structures was of great significance to the development of nonsacrificial and efficient anticorrosion materials.

11.
Nano Lett ; 20(10): 7144-7151, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32941049

RESUMO

Flexible optoelectronic devices attract considerable attention due to their prominent role in creating novel wearable apparatus for bionics, robotics, health care, and so forth. Although bulk single-crystalline perovskite-based materials are well-recognized for the high photoelectric conversion efficiency than the polycrystalline ones, their stiff and brittle nature unfortunately prohibits their application for flexible devices. Here, we introduce ultrathin single-crystalline perovskite film as the active layer and demonstrate a high-performance flexible photodetector with prevailing bending reliability. With a much-reduced thickness of 20 nm, the photodetector made of this ultrathin film can achieve a significantly increased responsivity as 5600A/W, 2 orders of magnitude higher than that of recently reported flexible perovskite photodetectors. The demonstrated 0.2 MHz 3 dB bandwidth further paves the way for high-speed photodetection. Notably, all its optoelectronic characteristics resume after being bent over thousands of times. These results manifest the great potential of single-crystalline perovskite ultrathin films for developing wearable and flexible optoelectronic devices.

12.
Proc Natl Acad Sci U S A ; 113(3): 584-9, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26729868

RESUMO

Developmental synchrony, the basis of uniform swarming, migration, and sexual maturation, is an important strategy for social animals to adapt to variable environments. However, the molecular mechanisms underlying developmental synchrony are largely unexplored. The migratory locust exhibits polyphenism between gregarious and solitarious individuals, with the former displaying more synchronous sexual maturation and migration than the latter. Here, we found that the egg-hatching time of gregarious locusts was more uniform compared with solitarious locusts and that microRNA-276 (miR-276) was expressed significantly higher in both ovaries and eggs of gregarious locusts than in solitarious locusts. Interestingly, inhibiting miR-276 in gregarious females and overexpressing it in solitarious females, respectively, caused more heterochronic and synchronous hatching of progeny eggs. Moreover, miR-276 directly targeted a transcription coactivator gene, brahma (brm), resulting in its up-regulation. Knockdown of brm not only resulted in asynchronous egg hatching in gregarious locusts but also impaired the miR-276-induced synchronous egg hatching in solitarious locusts. Mechanistically, miR-276 mediated brm activation in a manner that depended on the secondary structure of brm, namely, a stem-loop around the binding site of miR-276. Collectively, our results unravel a mechanism by which miR-276 enhances brm expression to promote developmental synchrony and provide insight into regulation of developmental homeostasis and population sustaining that are closely related to biological synchrony.


Assuntos
Gafanhotos/genética , MicroRNAs/genética , Oviposição/genética , Regulação para Cima/genética , Animais , Sequência de Bases , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Hibridização in Situ Fluorescente , MicroRNAs/metabolismo , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fases de Leitura Aberta/genética , Ovário/metabolismo , Óvulo/metabolismo , RNA/química , RNA/genética , Interferência de RNA , Sítios de Splice de RNA/genética
13.
PLoS Genet ; 10(2): e1004206, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24586212

RESUMO

Phenotypic plasticity is ubiquitous and primarily controlled by interactions between environmental and genetic factors. The migratory locust, a worldwide pest, exhibits pronounced phenotypic plasticity, which is a population density-dependent transition that occurs between the gregarious and solitary phases. Genes involved in dopamine synthesis have been shown to regulate the phase transition of locusts. However, the function of microRNAs in this process remains unknown. In this study, we report the participation of miR-133 in dopamine production and the behavioral transition by negatively regulating two critical genes, henna and pale, in the dopamine pathway. miR-133 participated in the post-transcriptional regulation of henna and pale by binding to their coding region and 3' untranslated region, respectively. miR-133 displayed cellular co-localization with henna/pale in the protocerebrum, and its expression in the protocerebrum was negatively correlated with henna and pale expression. Moreover, miR-133 agomir delivery suppressed henna and pale expression, which consequently decreased dopamine production, thus resulting in the behavioral shift of the locusts from the gregarious phase to the solitary phase. Increasing the dopamine content could rescue the solitary phenotype, which was induced by miR-133 agomir delivery. Conversely, miR-133 inhibition increased the expression of henna and pale, resulting in the gregarious-like behavior of solitary locusts; this gregarious phenotype could be rescued by RNA interference of henna and pale. This study shows the novel function and modulation pattern of a miRNA in phenotypic plasticity and provides insight into the underlying molecular mechanisms of the phase transition of locusts.


Assuntos
Dopamina/biossíntese , Gafanhotos/genética , MicroRNAs/genética , Comportamento Social , Animais , Dopamina/genética , Regulação da Expressão Gênica , Gafanhotos/fisiologia , Fenótipo , Densidade Demográfica , Interferência de RNA
14.
Proc Natl Acad Sci U S A ; 108(10): 3882-7, 2011 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-21325054

RESUMO

The migratory locust, Locusta migratoria, shows a striking phenotypic plasticity. It transitions between solitary and gregarious phases in response to population density changes. However, the molecular mechanism underlying the phase-dependent behavior changes remains elusive. Here we report a genome-wide gene expression profiling of gregarious and solitary nymphs at each stadium of the migratory locust, and we identified the most differentially expressed genes in the fourth stadium of the two phases. Bioinformatics analysis indicated that the catecholamine metabolic pathway was the most significant pathway up-regulated in the gregarious phase. We found pale, henna, and vat1, involved in dopamine biosynthesis and synaptic release, were critical target genes related to behavioral phase changes in the locusts. The roles of these genes in mediating behavioral changes in the gregarious individuals were confirmed by RNAi and pharmacological intervention. A single injection of dopamine or its agonist initiated gregarious behavior. Moreover, continuous and multiple injections of a dopamine agonist coupled with crowding resulted in more pronounced gregarious behavior. Our study thus provides insights into the relationships between genes and behavior in phase transition of this important pest species.


Assuntos
Migração Animal , Catecolaminas/metabolismo , Gafanhotos/fisiologia , Animais , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Gafanhotos/genética , Gafanhotos/metabolismo , Espectrometria de Massas , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Interferência de RNA
15.
Pest Manag Sci ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629874

RESUMO

BACKGROUND: The pea leafminer, Liriomyza huidobrensis, is one of the most important insect pests on vegetables and ornamentals. The survival and egg-laying behavior of leafminers are markedly affected by the environment temperature. However, the mechanisms underlying the relationship between egg-laying and temperature are still largely unknown. RESULTS: Here, we find that leafminers have evolved an adaptive strategy to overcome the stress from high or low temperature by regulating oviposition-punching plasticity. We further show that this oviposition-punching plasticity is mediated by the expression of pyx in the ovipositor when subjected to disadvantageous temperature. Specifically, down-regulation of pyx expression in leafminers under low temperature stress led to a significant decrease in the swing numbers of ovipositor and puncture area of the egg spot, and consequently the lower amount of egg-laying compared to leafminers at ambient temperature. Conversely, activation of pyx expression under high temperature stress increased the swing numbers and puncture area, still resulting in a reduction of egg-laying amount. CONCLUSION: Thereby, leafminers are able to coordinate pyx channel expression level and accordingly depress the oviposition. Our study uncovers a molecular mechanism underlying the adaptive strategy in insects that can avoid disadvantageous temperature for reproducing offspring. © 2024 Society of Chemical Industry.

16.
Curr Opin Insect Sci ; 59: 101098, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37541387

RESUMO

Pheromone plasticity is widely observed in insects and enhances their survival, adaptation, and reproductive success. Aggregation pheromones, which cause notable individual aggregation and consequently impact agriculture and human life, are renowned for their special function. Here, we present a review of research progress regarding pheromone plasticity in three typical aggregative insects: locusts, bark beetles, and cockroaches. These insects are major pest species with considerable impacts on the social economy and public health. Numerous studies have demonstrated the plasticity of aggregation pheromones in different populations of these insect species. Although pheromone chemicals and compositions vary across the three groups, the plasticity of aggregation pheromones is significantly impacted by population density, location, food resources, and gut symbiotic microorganisms, indicating the complexity of pheromone plasticity regulated by multiple factors. Finally, we discuss the potential application of pheromone plasticity in basic research and pest management.

17.
Science ; 380(6644): 537-543, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37141362

RESUMO

Many animals engage in cannibalism to supplement their diets. Among dense populations of migratory locusts, cannibalism is prevalent. We show that under crowded conditions, locusts produce an anticannibalistic pheromone called phenylacetonitrile. Both the degree of cannibalism and the production of phenylacetonitrile are density dependent and covary. We identified the olfactory receptor that detects phenylacetonitrile and used genome editing to make this receptor nonfunctional, thereby abolishing the negative behavioral response. We also inactivated the gene underlying phenylacetonitrile production and show that locusts that lack this compound lose its protection and are more frequently exposed to intraspecific predation. Thus, we reveal an anticannibalistic feature built on a specifically produced odor. The system is very likely to be of major importance in locust population ecology, and our results might therefore provide opportunities in locust management.


Assuntos
Acetonitrilas , Canibalismo , Aglomeração , Gafanhotos , Feromônios , Animais , Acetonitrilas/metabolismo , Gafanhotos/genética , Gafanhotos/metabolismo , Feromônios/genética , Feromônios/metabolismo
18.
J Nephrol ; 36(4): 1027-1035, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36786975

RESUMO

BACKGROUND: Patients with crescentic glomerulonephritis have a poor prognosis despite immunosuppressive therapy. This study investigated the clinicopathologic features, outcomes, and risk factors in Chinese patients with crescentic glomerulonephritis. METHODS: The multicenter cohort study included consecutive individuals with crescentic glomerulonephritis and a minimum follow-up of 1 year after biopsy, observed from January 2013 to December 2020. Primary outcome was the occurrence of death or end stage kidney disease (ESKD) for surviving patients. Multivariable adjusted Cox proportional hazards model was applied. RESULTS: Of 109 patients enrolled, 73 (67%) suffered primary outcomes, including 39 deaths, and 34 ESKDs among the 70 surviving patients, with a mean follow-up of 26 months. All 26 patients with over 90% glomeruli with crescents reached a primary outcome. Patients with type III crescentic glomerulonephritis had the worst prognosis for primary outcomes (HR, 95% CI for type I vs. type III: 0.29, 0.14-0.58; type II vs. type III: 0.44, 0.22-0.91) and a significantly faster rate of eGFR decline after adjusting for baseline variables. In patients with 75%-100% glomeruli with crescents, the risk of a primary outcome increased nearly fourfold (HR 3.96; 95% CI 2.17-7.23) compared with patients with 50-75% glomeruli with crescents after adjusting for baseline variables. Type of crescentic glomerulonephritis and percentage of cellular and total glomeruli with crescents were independent risk factors for early primary outcomes (within 6 months). CONCLUSIONS: This study provides new insights into crescentic glomerulonephritis, including a description of the worst outcomes occurring in patients with type III crescentic glomerulonephritis, and suggests that the quantification of the percentage of crescents may be of use for guiding therapeutic decisions, due to their role in identifying the risk of primary outcomes.


Assuntos
Glomerulonefrite Membranoproliferativa , Glomerulonefrite , Falência Renal Crônica , Humanos , Estudos de Coortes , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia , Falência Renal Crônica/etiologia , Glomérulos Renais/patologia , Doença Aguda , Fatores de Risco , Biópsia/efeitos adversos , Glomerulonefrite/complicações , Glomerulonefrite/diagnóstico , Glomerulonefrite/epidemiologia , Estudos Retrospectivos
19.
Elife ; 122023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814951

RESUMO

Animals must learn to ignore stimuli that are irrelevant to survival and attend to ones that enhance survival. When a stimulus regularly fails to be associated with an important consequence, subsequent excitatory learning about that stimulus can be delayed, which is a form of nonassociative conditioning called 'latent inhibition'. Honey bees show latent inhibition toward an odor they have experienced without association with food reinforcement. Moreover, individual honey bees from the same colony differ in the degree to which they show latent inhibition, and these individual differences have a genetic basis. To investigate the mechanisms that underly individual differences in latent inhibition, we selected two honey bee lines for high and low latent inhibition, respectively. We crossed those lines and mapped a Quantitative Trait Locus for latent inhibition to a region of the genome that contains the tyramine receptor gene Amtyr1 [We use Amtyr1 to denote the gene and AmTYR1 the receptor throughout the text.]. We then show that disruption of Amtyr1 signaling either pharmacologically or through RNAi qualitatively changes the expression of latent inhibition but has little or slight effects on appetitive conditioning, and these results suggest that AmTYR1 modulates inhibitory processing in the CNS. Electrophysiological recordings from the brain during pharmacological blockade are consistent with a model that AmTYR1 indirectly regulates at inhibitory synapses in the CNS. Our results therefore identify a distinct Amtyr1-based modulatory pathway for this type of nonassociative learning, and we propose a model for how Amtyr1 acts as a gain control to modulate hebbian plasticity at defined synapses in the CNS. We have shown elsewhere how this modulation also underlies potentially adaptive intracolonial learning differences among individuals that benefit colony survival. Finally, our neural model suggests a mechanism for the broad pleiotropy this gene has on several different behaviors.


To efficiently navigate their environment, animals must pay attention to cues associated with events important for survival while also dismissing meaningless signals. The difference between relevant and irrelevant stimuli is learned through a range of complex mechanisms that includes latent inhibition. This process allows animals to ignore irrelevant stimuli, which makes it more difficult for them to associate a cue and a reward if that cue has been unrewarded before. For example, bees will take longer to 'learn' that a certain floral odor signals a feeding opportunity if they first repeatedly encountered the smell when food was absent. Such a mechanism allows organisms to devote more attention to other stimuli which have the potential to be important for survival. The strength of latent inhibition ­ as revealed by how quickly and easily an individual can learn to associate a reward with a previously unrewarded stimulus ­ can differ between individuals. For instance, this is the case in honey bee colonies, where workers have the same mother but may come from different fathers. Such genetic variation can be beneficial for the hive, with high latent inhibition workers being better suited for paying attention to and harvesting known resources, and their low latent inhibition peers for discovering new ones. However, the underlying genetic and neural mechanisms underpinning latent inhibition variability between individuals remained unclear. To investigate this question, Latshaw et al. cross-bred bees from high and low latent inhibition genetic lines. The resulting progeny underwent behavioral tests, and the genome of low and high latent inhibition individuals was screened. These analyses revealed a candidate gene, Amtyr1, which was associated with individual variations in the learning mechanism. Further experiments showed that blocking or disrupting the production the AMTYR1 protein led to altered latent inhibition behavior as well as dampened attention-related processing in recordings from the central nervous system. Based on these findings, a model was proposed detailing how varying degrees of Amtyr1 activation can tune Hebbian plasticity, the brain mechanism that allows organisms to regulate associations between cues and events. Importantly, because of the way AMTYR1 acts in the nervous system, this modulatory role could go beyond latent inhibition, with the associated gene controlling the activity of a range of foraging-related behaviors. Genetic work in model organisms such as fruit flies would allow a more in-depth understanding of such network modulation.


Assuntos
Olfato , Tiramina , Humanos , Abelhas , Animais , Olfato/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Atenção
20.
Nanoscale ; 14(34): 12358-12376, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-35972035

RESUMO

The use of heterojunctions for metal corrosion protection is a highly innovative and challenging task. Based on the composition and structure of tungsten oxide-based heterojunctions, Z-scheme heterojunctions were designed and synthesized by the electrostatic self-assembly method using energy band-matched g-C3N4 and WO3 materials. Applied in the field of anticorrosion, they overcame the problems of poor reduction ability and transmission inefficiency of traditional materials. The Z-scheme heterojunctions ensured unidirectional electron transfer, while the aggregation of the retained strongly reduced electrons on the surface of the iron substrates provided a strong driving force for retarding corrosion occurrence. Meanwhile, the inherent shielding properties of the two-dimensional material g-C3N4 and the confinement of chloride ions as an electroactive layer hindered the penetration of the corrosive solution. After being corroded for 72 h, the corrosion impedance of the g-C3N4/WO3 heterojunction system was improved by 640.11% compared with the epoxy resin coating. In addition, the g-C3N4/W18O49 heterojunction was synthesized by using mixed valence tungsten oxide, which overcame the problems of photogenerated electron yield and lifetime, and enhanced the anticorrosion performance compared with a single g-C3N4 phase. This research provided ideas for designing efficient and environmentally friendly heterojunction anticorrosion materials.

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