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1.
Insect Mol Biol ; 33(1): 17-28, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37707297

RESUMO

In insects, vitellogenin (Vg) is generally viewed as a female-specific protein. Its primary function is to supply nutrition to developing embryos. Here, we reported Vg from the male adults of a natural predator, Chrysopa pallens. The male Vg was depleted by RNAi. Mating with Vg-deficient male downregulated female Vg expression, suppressed ovarian development and decreased reproductive output. Whole-organism transcriptome analysis after male Vg knockdown showed no differential expression of the known spermatogenesis-related regulators and seminal fluid protein genes, but a sharp downregulation of an unknown gene, which encodes a testis-enriched big protein (Vcsoo). Separate knockdown of male Vg and Vcsoo disturbed the assembly of spermatid cytoplasmic organelles in males and suppressed the expansion of ovary germarium in mated females. These results demonstrated that C. pallens male Vg signals through the downstream Vcsoo and regulates male and female reproduction.


Assuntos
Testículo , Vitelogeninas , Feminino , Masculino , Animais , Vitelogeninas/genética , Vitelogeninas/metabolismo , Insetos/genética , Reprodução , Gametogênese
2.
J Am Chem Soc ; 145(13): 7397-7407, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36961942

RESUMO

Nickel-rich layered oxides (NLOs) are considered as one of the most promising cathode materials for next-generation high-energy lithium-ion batteries (LIBs), yet their practical applications are currently challenged by the unsatisfactory cyclability and reliability owing to their inherent interfacial and structural instability. Herein, we demonstrate an approach to reverse the unstable nature of NLOs through surface solid reaction, by which the reconstructed surface lattice turns stable and robust against both side reactions and chemophysical breakdown, resulting in improved cycling performance. Specifically, conformal La(OH)3 nanoshells are built with their thicknesses controlled at nanometer accuracy, which act as a Li+ capturer and induce controlled reaction with the NLO surface lattices, thereby transforming the particle crust into an epitaxial layer with localized Ni/Li disordering, where lithium deficiency and nickel stabilization are both achieved by transforming oxidative Ni3+ into stable Ni2+. An optimized balance between surface stabilization and charge transfer is demonstrated by a representative NLO material, namely, LiNi0.83Co0.07Mn0.1O2, whose surface engineering leads to a highly improved capacity retention and excellent rate capability with a strong capability to inhibit the crack of NLO particles. Our study highlights the importance of surface chemistry in determining chemical and structural behaviors and paves a research avenue in controlling the surface lattice for the stabilization of NLOs toward reliable high-energy LIBs.

3.
Phys Chem Chem Phys ; 25(29): 19795-19803, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449881

RESUMO

As one of the promising next-generation energy storage systems, lithium-sulfur (Li-S) batteries have been the subject of much recent attention. However, the polysulfide shuttle effect remains problematic owing to the dissolution of intermediate polysulfide species in the electrolyte and the sluggish reaction dynamics in Li-S batteries. To overcome these issues, this work reports an effective strategy for enhancing the electrochemical performance of Li-S batteries using single atom Zn doping on the S-terminated Ti2C MXenes (Ti2-xZnxCS2). Spin-polarized density functional theory (DFT) calculations were performed to elucidate the interactions of lithium polysulfides (LiPSs) and the Ti2-xZnxCS2 surface in terms of geometric and electronic properties, as well as the delithiation process of Li2S on the Ti2-xZnxCS2 surface. It is found that doping single atom Zn could induce a new Lewis acid-based sites, which could provide proper affinity toward LiPSs. Combined with the metallic character, a low Li diffusion barrier and high catalytic activity for the delithiation process of Li2S, makes Ti2-xZnxCS2 a promising cathode material for Li-S batteries. The results demonstrate the importance of surface chemistry and the electronic structure of MXenes in LiPSs' adsorption and catalysis capability. We believe that our findings provide insights into the recent experimental results and guidance for the preparation and practical application of MXenes in Li-S batteries.

4.
Bull Entomol Res ; 113(1): 49-62, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35904166

RESUMO

Understanding predator-prey interactions is essential for successful pest management by using predators, especially for the suppression of novel invasive pest. The green lacewing Chrysopa formosa is a promising polyphagous predator that is widely used in the biocontrol of various pests in China, but information on the control efficiency of this predator against the seriously invasive pest Spodoptera frugiperda and native Spodoptera litura is limited. Here we evaluated the predation efficiency of C. formosa adults on eggs and first- to third-instar larvae of S. frugiperda and S. litura through functional response experiments and determined the consumption capacity and prey preference of this chrysopid. Adults of C. formosa had a high consumption of eggs and earlier instar larvae of both prey species, and displayed a type II functional response on all prey stages. Attack rates of the chrysopid on different prey stages were statistically similar, but the handling time increased notably as the prey developed. The highest predation efficiency and shortest-handling time were observed for C. formosa feeding on Spodoptera eggs, followed by the first-instar larvae. C. formosa exhibited a significant preference for S. litura over S. frugiperda in a two-prey system. In addition, we summarized the functional response and predation efficiency of several chrysopids against noctuid pests and made a comparison with the results obtained from C. formosa. These results indicate that C. formosa has potential as an agent for biological control of noctuid pests, particularly for the newly invasive pest S. frugiperda in China.


Assuntos
Controle Biológico de Vetores , Comportamento Predatório , Animais , Spodoptera/fisiologia , Taiwan , Larva/fisiologia , Comportamento Predatório/fisiologia
5.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614060

RESUMO

Cathepsin L protease, which belongs to the papain-like cysteine proteases family, is an important player in many physiological and pathological processes. However, little was known about the role of cathepsin L in ladybird beetles (Coccinella septempuctata Linnaeus) during diapause. Here, we analyzed the characteristics of cathepsin L (CsCatL) in the females of C. septempunctata and its role during the diapause of the ladybeetle. CsCatL was cloned and identified from beetle specimens by rapid amplification of cDNA-ends (RACE). The cDNA sequence of CsCatL was 971 bp in length, including an 843 bp open reading frame encoding a protein of 280 amino acids. It was identified as the cathepsin L group by phylogenetic analysis. Knockdown of CsCatL by RNA interference led to decreased expression levels of fatty acid synthase 2 (fas 2) genes and suppressed lipid accumulation. Furthermore, silencing the CsCatL gene distinctly reduced diapause-related features and the survival of female C. spetempunctata under diapause-inducing conditions. The results suggested that the CsCatL gene was involved in fatty acid biosynthesis and played a crucial role in the survival of adult C. septempunctata during the diapause preparation stage.


Assuntos
Besouros , Diapausa , Animais , Feminino , Catepsina L/genética , Catepsina L/metabolismo , Filogenia , DNA Complementar , Besouros/metabolismo , Diapausa/genética , Lipídeos
6.
Nanotechnology ; 32(6): 065501, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33075753

RESUMO

The adsorption and gas sensing properties of black arsenene (B-As) regarding sulfur hexafluoride (SF6) and its six decompositions (SOF2, SO2F2, SO2, H2S, HF, and CF4) are investigated using density functional theory combined with the nonequilibrium Green's function. The sensitivity of B-As is evaluated by considering the most stable adsorption configuration, adsorption energy, work function, recovery time, local density of states, and charge transfer between the gas molecules and B-As. It is demonstrated that B-As is more sensitive to the SO2 molecule than to the other decompositions. Additionally, the adsorption strength can be manipulated by controlling the external electric field (E-field). The application of tensile biaxial strain results in more isotropic electrical conductance of B-As, and it can also effectively enhance the response toward SO2. For example, under a 1% equibiaxial tensile strain, a 132% response can be obtained along the zigzag direction. This work suggests the promising prospects of B-As-based gas sensors for detecting SO2 among SF6 decompositions.

7.
Arch Insect Biochem Physiol ; 107(3): e21796, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34076304

RESUMO

MicroRNAs (miRNAs) are a type of small noncoding RNAs that regulate gene expression at the posttranscriptional level and can influence significant biological processes. Arma chinensis (Hemiptera: Pentatomidae) is a predaceous insect species that preys upon a wide variety of insect pests. It is important to explore and understand the molecular mechanisms involving miRNAs in regulating developmental and other gene expression for beneficial insects. However, examination of miRNAs associated with Hemiptera, especially predatory bugs, has been absent or scarce. This study represents the first comprehensive analysis of predatory bug A. chinensis encoded miRNAs through high throughput sequencing and predicts genes and biological processes regulated by the newly identified miRNAs through analyzing their differential expression in and across five nymphal instars. A total of 64 A. chinensis miRNAs, including 46 conserved miRNAs and 18 novel miRNAs, were identified by analysis of high throughput sequence reads mapped to the genome. A total of 2913 potential gene targets for these 64 miRNAs were predicted by comprehensive analyses utilizing miRanda, PITA, and RNAhybrid. Gene Ontology annotation of predicted target genes of A. chinensis suggested the key processes regulated by miRNAs involved biological processes, regulation of cellular processes, and transporter activity. Kyoto Encyclopedia of Genes and Genomes pathway predictions included the Toll and Imd signaling pathway, Valine, leucine and isoleucine degradation, Steroid biosynthesis, the AGE-RAGE signaling pathway in diabetic complications, and Alanine, aspartate and glutamate metabolism. This newly identified miRNAs through analyzing their differential expression, assessment of their predicted functions forms a foundation for further investigation of specific miRNAs.


Assuntos
Heterópteros/metabolismo , MicroRNAs/metabolismo , Animais , Perfilação da Expressão Gênica , Ninfa/metabolismo , Análise de Sequência de RNA
8.
Bull Entomol Res ; 111(3): 270-281, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32993843

RESUMO

Peristenus spretus (Hymenoptera: Braconidae) is one of the most important endoparasitoids used for biological control of the green mirid bug, Apolygus lucorum Meyer-Dür (Heteroptera: Miridae). However, what we know about its reproductive genetics is very limited. Here, the composition of ovarian proteins in P. spretus was analyzed. Mass spectrum data searched against the non-redundant NCBI protein and UniProt protein database identified 1382 proteins and revealed an enrichment of the heat shock protein 83 (HSP83) in P. spretus ovary. The Pshsp83 complete cDNA is 2175 bp in length and encodes a protein of 724 amino acids with a calculated molecular mass of 83.4 kDa and a theoretical isoelectric point of 4.87. Transcription of Pshsp83 appeared from days 1 to 13 post-emergence and peaked at 13th day. Immuno-localization showed that the HSP83 protein was present in cytoplasm of germarium and in egg chambers of the whole ovariole. The transcript abundance of Pshsp83 fluctuated drastically after heat shocks at different temperatures and the maximum emerged at 35°C. The exposure to 35°C caused no dramatic effects on reproductive parameters of adult females such as pupation rate, cocoon weight, emergence rate, sex ratio and developmental duration, but did on longevity. These results suggested that the HSP83 protein is involved in life-span regulation in the P. spretus.


Assuntos
Proteínas de Choque Térmico/metabolismo , Himenópteros/metabolismo , Ovário/metabolismo , Animais , Agentes de Controle Biológico/metabolismo , DNA Complementar/genética , Feminino , Expressão Gênica , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico , Himenópteros/genética , Himenópteros/fisiologia , Longevidade , Espectrometria de Massas , Oviposição , Parasitos/genética , Parasitos/metabolismo , Parasitos/fisiologia , Proteoma , Proteômica , Reprodução , Vespas/genética , Vespas/metabolismo , Vespas/fisiologia
9.
BMC Cancer ; 20(1): 1089, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176740

RESUMO

BACKGROUND: This study is designed to investigate the clinical value of systemic chemotherapy combined with bronchoscopic interventional cryotherapy in the treatment of lung cancer. METHODS: A total of 412 lung cancer patients admitted to Cangzhou People's Hospital from March 2018 to March 2020 were collected and divided into test group and control group based on their treatment schedules. The test group received systemic chemotherapy combined with bronchoscopic interventional cryotherapy, while the control group received systemic chemotherapy alone. Tumor objective response rate (ORR), disease control rate (DCR), serum tumor marker levels, serum matrix metalloproteinase (MMP) content, T cell subset level, survival time and adverse reactions of the two groups were observed. RESULTS: The ORR and DCR of the test group were better than those of the control group, while those of the non-small cell lung cancer (NSCLC) patients in the test group were better than patients with small-cell lung cancer (SCLC) (P <  0.05). There was no significant difference in serum tumor marker levels, MMP content and T cell subset level between the two groups before treatment. After treatment, the serum tumor marker levels along with serum MMP-2, MMP-9 and CD8+ levels in the test group decreased more remarkably, while CD4+ and CD4+/CD8+ levels increased more significantly than those in the control group (P <  0.05). The serum MMP-2 and MMP-9 of NSCLC patients in the test group decreased more remarkably than those of SCLC patients, while there was no significant difference in CD8+, CD4+ and CD4+/CD8+. The progression-free survival and overall survival of the test group were obviously longer than those of the control group. The same trend was observed in NSCLC patients compared with SCLC patients in the test group (P <  0.05). CONCLUSIONS: Systemic chemotherapy combined with bronchoscopic interventional cryotherapy for lung cancer has good clinical efficacy and safety, and can be widely used in clinical practice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Crioterapia/métodos , Neoplasias Pulmonares/terapia , Carcinoma de Pequenas Células do Pulmão/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Casos e Controles , Terapia Combinada , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Pequenas Células do Pulmão/patologia , Taxa de Sobrevida , Resultado do Tratamento
10.
Phys Chem Chem Phys ; 21(44): 24499-24505, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31687701

RESUMO

Arsenene is an emerging two-dimensional material similar to its group-V isologue phosphorene. Based on first-principles calculations and finite-temperature ab initio molecular dynamics (AIMD), we investigated the dynamical stability and electronic properties of three competing phases of two-dimensional (2D) arsenic, namely γ-As, the newly discovered δ'-As, and s/o-As. Phonon calculations and AIMD results confirm their dynamical stabilities. It is also found that the band structures of these allotropes can be effectively engineered by changing the number of layers or in-layer strain, realizing direct-indirect bandgap and metal-insulator transitions. The highly tunable electronic structures and the broad range bandgaps evidence potential applications in nanoelectronics and optoelectronics. Moreover, δ'-As is predicted to transform to a higher symmetry δ-As phase when the number of layers is sufficiently large. An intriguing phenomenon unveiled is the potential hybridization of different allotropes at an energy cost lower than 0.02 eV Å-1. This becomes particularly valuable for assembling heterostructures with different well-defined regions in one contiguous arsenene layer.

11.
J Am Chem Soc ; 140(46): 15883-15888, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30265000

RESUMO

Optimization of carrier concentration plays an important role on maximizing thermoelectric performance. Existing efforts mainly focus on aliovalent doping, while intrinsic defects (e.g., vacancies) provide extra possibilities. Thermoelectric GeTe intrinsically forms in off-stoichiometric with Ge-vacancies and Ge-precipitates, leading to a hole concentration significantly higher than required. In this work, Sb2Te3 having a smaller cation-to-anion ratio, is used as a solvend to form solid solutions with GeTe for manipulating the vacancies. This is enabled by the fact that each substitution of 3 Ge2+ by only 2 Sb3+ creates 1 Ge vacancy, because of the overall 1:1 cation-to-anion ratio of crystallographic sites in the structure and by the charge neutrality. The increase in the overall Ge-vacancy concentration facilitates Ge-precipitates to be dissolved into the matrix for reducing the hole concentration. In a combination with known reduction in hole concentration by Pb/Ge-substitution, a full optimization on hole concentration is realized. In addition, the resultant high-concentration point defects including both vacancies and substitutions strongly scatter phonons and reduce the lattice thermal conductivity to the amorphous limit. These enable a significantly improved thermoelectric figure of merit at working temperatures of thermoelectric GeTe.

12.
Phys Chem Chem Phys ; 19(39): 27116-27122, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28967016

RESUMO

The adsorption and dissociation reactions of H2S on TiC(001) are investigated using first-principles density functional theory calculations. The geometric and electronic structures of the adsorbed S-based species (including H2S, SH and S) on TiC(001) are analyzed in detail. It is found that the H2S is bound weakly, while SH and atomic S are bound strongly on the TiC(001) surface. The transition state calculations show that the formation of SH from H2S (H2S → SH + H) is very easy, while the presence of a co-adsorbed H will inhibit the further dissociation of SH (SH + H → S + H + H). In contrast, the hydrogenation of the adsorbed SH is rather easy (SH + H → H2S). Therefore, the dissociative SH can be removed via the hydrogenation reaction. It is concluded that it is difficult for H2S to dissociate completely to form atomic S and poison the TiC surface. The results will further provide understanding of the mechanism of the sulfur tolerance of the TiC anode of proton exchange membrane fuel cells (PEMFCs).

13.
Phys Chem Chem Phys ; 19(36): 24879-24885, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28869275

RESUMO

The tolerance of sulfur poisoning of α-Mo2C(0001) surfaces with different Pt coverages is investigated combining the density functional theory (DFT) results with thermodynamics data using the ab initio atomistic thermodynamic method. It is found that on Mo2C(0001), Pt clusters tend to form two dimensional planar structures instead of aggregating. The clean Mo2C(0001) surface interacts with sulfides very strongly and is susceptible to sulfur poisoning. With increasing the coverage of Pt on the Mo2C surface, the interaction between sulfur and substrate is weakened. The sulfur tolerance ability increases in the order of Mo2C ≈ Pt1/Mo2C < Pt4/Mo2C < Pt8/Mo2C, where the coverage of Pt on the Mo2C plays a very effective role. The results provide theoretical guidance for designing Mo2C based catalysts with high activity and high sulfur resistance.

14.
J Chem Phys ; 144(20): 204703, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27250321

RESUMO

The adsorption, diffusion, and dissociation of O2 on the palladium monolayer supported on TiC(001) surface, MLPd/TiC(001), are investigated using ab initio density functional theory calculations. Strong adhesion of palladium monolayer to the TiC(001) support, accompanied by a modification of electronic structure of the supported palladium, is evidenced. Compared with Pt(111) surface, the MLPd/TiC(001) can enhance the adsorption of O2, leading to comparable dissociation barrier and a smaller diffusion barrier of O2. Whilst the adsorption strength of atomic O (the dissociation product of O2) on MLPd/TiC(001) is similar to that on the Pt(111) surface, possessing high mobility, our theoretical results indicate that MLPd/TiC(001) may serve as a good catalyst for the oxygen reduction reaction.

15.
Pestic Biochem Physiol ; 118: 71-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25752433

RESUMO

Coatomer and v-ATPase are two genes expressed in insect midgut epithelial cells and their knockdown is lethal to insect larvae. To investigate the RNAi response mediated by multiple siRNA duplexes, partial length cDNA of Helicoverpa armigera coatomer ß and v-ATPase A was cloned and siRNA feeding-based RNAi was performed. Simultaneous ingestion of siRNAs specific to the H. armigera coatomer ß and v-ATPase A led to co-silencing of the target genes and reduction in larval survival rate and weight gain. These results suggest that silencing two genes by feeding of multiple siRNAs is a good RNAi strategy.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Insetos/genética , Larva/crescimento & desenvolvimento , Mariposas/genética , Controle Biológico de Vetores/métodos , Interferência de RNA , RNA Interferente Pequeno/genética , Adenosina Trifosfatases/metabolismo , Animais , Comportamento Alimentar , Gossypium/parasitologia , Proteínas de Insetos/metabolismo , Larva/genética , Larva/fisiologia , Mariposas/enzimologia , Mariposas/crescimento & desenvolvimento , Mariposas/fisiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , RNA Interferente Pequeno/metabolismo , Aumento de Peso
16.
Transgenic Res ; 23(1): 145-52, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23949691

RESUMO

Plant-mediated RNAi has been developed as a powerful weapon in the fight against agricultural insect pests. The gap gene hunchback (hb) is of crucial importance in insect axial patterning and knockdown of hb is deforming and lethal to the next generation. The peach potato aphid, Myzus persicae (Sulzer), has many host plants and can be found throughout the world. To investigate the effect of plant-mediated RNAi on control of this insect, the hb gene in M. persicae was cloned, plant RNAi vector was constructed, and transgenic tobacco expressing Mphb dsRNA was developed. Transgenic tobacco had a different integration pattern of the transgene. Bioassays were performed by applying neonate aphids to homozygous transgenic plants in the T2 generation. Results revealed that continuous feeding of transgenic diet reduced Mphb mRNA level in the fed aphids and inhibited insect reproduction, indicating successful knockdown of the target gene in M. persicae by plant-mediated RNAi.


Assuntos
Nicotiana/genética , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Interferência de RNA , Animais , Afídeos/patogenicidade , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/parasitologia , RNA de Cadeia Dupla/genética , Reprodução/genética , Nicotiana/parasitologia
17.
Sci Total Environ ; 924: 171329, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462006

RESUMO

Phenolic compounds, abundant secondary metabolites in plants, profoundly influence soil ecosystems, plant growth, and interactions with herbivores. In this study, we explore the intricate relationships between phenolics, soil microbes, and gall formation in Ageratina adenophora (A. adenophora), an invasive plant species in China known for its allelopathic traits. Using metabolomic and microbial profiling, significant differences in soil microbial composition and metabolite profiles were observed between bulk and rhizosphere soil samples. Phenolics influenced bacterial communities, with distinct microbial populations enriched in each soil type. Additionally, phenolics impacted soil metabolic processes, with variations observed in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis between different soil treatments. Analysis of phenolic content in plant and soil samples revealed considerable variations, with higher concentrations observed in certain plant tissues and soil types. Bioactive phenols extracted from plant and soil samples were identified using gas chromatography/mass spectrometry (GC-MS), providing insights into the diverse chemical composition of these compounds. Furthermore, the effects of phenolics on plant growth and gall formation were investigated. Phenols exhibited both stimulatory and inhibitory effects on plant growth, with optimal concentrations promoting emergence but higher concentrations hindering growth. Gall formation was influenced by phenolic concentrations, leading to structural alterations in stem tissue and gall morphology. Histochemical analysis revealed starch and lipid accumulation in gall tissues, indicating metabolic changes induced by phenolics. The presence of phenolics disrupted tissue structures and influenced vascular bundle orientation in gall tissues. Overall, our study highlights the multifaceted roles of phenolic compounds in soil ecosystems, plant development, and gall formation, facilitating the utilization of secondary metabolites in agriculture.


Assuntos
Ecossistema , Solo , Solo/química , Desenvolvimento Vegetal , Plantas/metabolismo , Fenóis/metabolismo , Dispersão Vegetal , Microbiologia do Solo , Raízes de Plantas/metabolismo
18.
Pest Manag Sci ; 80(7): 3665-3674, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38459943

RESUMO

BACKGROUND: The ladybeetle, Coccinella septempunctata, an important predator, is widely used to control aphids, whiteflies, mites, thrips, and lepidopteran pests. Diapause control technology is key to extending C. septempunctata shelf-life and commercialization. Lipid accumulation is a major feature of reproductive diapause, but the function of AKH signaling as a regulator of lipid mobilization in reproductive diapause remains unclear. This study aimed to identify and characterize AKH and AKHR genes, and clarify their functions in reproductive diapause. RESULTS: The relative expression levels of CsAKH and CsAKHR were the highest in the head and fat body, respectively, and were significantly decreased under diapause conditions, both in developmental stages and tissues (head, midgut, fat body, and ovary). Furthermore, CsAKH and CsAKHR expression was increased significantly after juvenile hormone (JH) injection, but CsMet silencing significantly inhibited CsAKH and CsAKHR expression, whereas CsMet knockdown blocked the induction effect of JH. CsAKH and CsAKHR knockdown significantly reduced water content, increased lipid storage, and promoted the expression of genes related to lipid synthesis, but significantly blocked ovarian development, and induced forkhead box O (FOXO) gene expression in C. septempunctata under reproduction conditions. By contrast, injection of AKH peptide significantly inhibited FOXO expression, reduced lipid storage, and increased water content in C. septempunctata under diapause conditions. CONCLUSION: These results indicate that CsAKH and CsAKHR are involved in the regulation of lipid accumulation and ovarian development during diapause in C. septempunctata, and provide a promising target for manipulating C. septempunctata diapause. © 2024 Society of Chemical Industry.


Assuntos
Besouros , Diapausa de Inseto , Hormônios de Inseto , Proteínas de Insetos , Oligopeptídeos , Ácido Pirrolidonocarboxílico , Reprodução , Transdução de Sinais , Animais , Hormônios de Inseto/metabolismo , Hormônios de Inseto/genética , Besouros/fisiologia , Besouros/metabolismo , Besouros/crescimento & desenvolvimento , Besouros/genética , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Oligopeptídeos/metabolismo , Feminino , Metabolismo dos Lipídeos
19.
Heliyon ; 10(11): e32478, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38933978

RESUMO

Vertebrate testosterone, an androgen present in the testes, is essential for male fertility. Vertebrate-type steroid hormones have been identified in insects, but their function remains unknown. Insect vitellogenin (Vg) is usually a female-specific protein involved in reproductive processes. However, males of some species, such as the green lacewing Chrysopa pallens, have Vg. Here, we demonstrated that the knockdown of C. pallens male Vg by RNAi significantly shortened the lifespan of males, suppressed the reproduction of post-mating females, and strikingly reduced the abundance of several immune-related compounds, including testosterone. LC-MS/MS revealed that C. pallens male testosterone had the same structure and molecular mass as vertebrate testosterone. Topical testosterone application partially restored the lifespan of Vg-deficient males and the reproduction of post-mating females. These results suggest that vertebrate-type testosterone maintains male longevity and female reproduction under the control of the male Vg in C. pallens.

20.
Adv Sci (Weinh) ; : e2400486, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978328

RESUMO

The risk for suffering immune checkpoint inhibitors (ICIs)-associated myocarditis increases in patients with pre-existing conditions and the mechanisms remain to be clarified. Spatial transcriptomics, single-cell RNA sequencing, and flow cytometry are used to decipher how anti-cytotoxic T lymphocyte antigen-4 m2a antibody (anti-CTLA-4 m2a antibody) aggravated cardiac injury in experimental autoimmune myocarditis (EAM) mice. It is found that anti-CTLA-4 m2a antibody increases cardiac fibroblast-derived C-X-C motif chemokine ligand 1 (Cxcl1), which promots neutrophil infiltration to the myocarditic zones (MZs) of EAM mice via enhanced Cxcl1-Cxcr2 chemotaxis. It is identified that the C-C motif chemokine ligand 5 (Ccl5)-neutrophil subpopulation is responsible for high activity of cytokine production, adaptive immune response, NF-κB signaling, and cellular response to interferon-gamma and that the Ccl5-neutrophil subpopulation and its-associated proinflammatory cytokines/chemokines promoted macrophage (Mφ) polarization to M1 Mφ. These altered infiltrating landscape and phenotypic switch of immune cells, and proinflammatory factors synergistically aggravated anti-CTLA-4 m2a antibody-induced cardiac injury in EAM mice. Neutralizing neutrophils, Cxcl1, and applying Cxcr2 antagonist dramatically alleviates anti-CTLA-4 m2a antibody-induced leukocyte infiltration, cardiac fibrosis, and dysfunction. It is suggested that Ccl5-neutrophil subpopulation plays a critical role in aggravating anti-CTLA-4 m2a antibody-induced cardiac injury in EAM mice. This data may provide a strategic rational for preventing/curing ICIs-associated myocarditis.

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