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1.
Insect Mol Biol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949741

RESUMO

Transcriptomic data have been used to study sex chromosome dosage compensation (SCDC) in approximately 10 Lepidoptera ZW species, yielding a consensus compensation pattern of Z ≈ ZZ < AA . $$ \approx \mathrm{ZZ}<\mathrm{AA}. $$ It remains unclear whether this compensation pattern holds when examining more Lepidoptera ZW species and/or using proteomic data to analyse SCDC. Here we combined transcriptomic and proteomic data as well as transcriptional level of six individual Z genes to reveal the SCDC pattern in Helicoverpa armigera, a polyphagous lepidopteran pest of economic importance. Transcriptomic analysis showed that the Z chromosome expression of H. armigera was balanced between male and female but substantially reduced relative to autosome expression, exhibiting an SCDC pattern of Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ . When using H. amigera midgut proteomic data, the SCDC pattern of this species changed from Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ at transcriptomic level to Z = ZZ = AA at the proteomic level. RT-qPCR analysis of transcript abundance of six Z genes found that compensation for each Z gene could vary from no compensation to overcompensation, depending on the individual genes and tissues tested. These results demonstrate for the first time the existence of a translational compensation mechanism, which is operating in addition to a translational mechanism, such as has been reported in other lepidopteran species. And the transcriptional compensation mechanism functions to accomplish Z chromosome dosage balance between the sexes (M = F on the Z chromosome), whereas the translation compensation mechanism operates to achieve dosage compensation between Z chromosome and autosome (Z = AA).

2.
Pestic Biochem Physiol ; 198: 105744, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38225087

RESUMO

Cry2Ab is one of the important alternative Bt proteins that can be used to manage insect pests resistant to Cry1A toxins and to expand the insecticidal spectrum of pyramided Bt crops. Previous studies have showed that vacuolar H+-ATPase subunits A and B (V-ATPase A and B) may be involved in Bt insecticidal activities. The present study investigated the role of V-ATPases subunit E in the toxicity of Cry2Ab in Helicoverpa amigera. RT-PCR analysis revealed that oral exposure of H. amigera larvae to Cry2Ab led to a significant reduction in the expression of H. armigera V-ATPase E (HaV-ATPase E). Ligand blot, homologous and heterologous competition experiments confirmed that HaV-ATPases E physically and specifically bound to activated Cry2Ab toxin. Heterologous expressing of HaV-ATPase E in Sf9 cells made the cell line more susceptible to Cry2Ab, whereas knockdown of the endogenous V-ATPase E in H. zea midgut cells decreased Cry2Ab's cytotoxicity against this cell line. Further in vivo bioassay showed that H. armigera larvae fed a diet overlaid with both Cry2Ab and E. coli-expressed HaV-ATPase E protein suffered significantly higher mortality than those fed Cry2Ab alone. These results support that V-ATPases E is a putative receptor of Cry2Ab and can be used to improve Cry2Ab toxicity and manage Cry2Ab resistance at least in H. armigera.


Assuntos
Bacillus thuringiensis , Inseticidas , Mariposas , Animais , Helicoverpa armigera , Endotoxinas/toxicidade , Endotoxinas/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Escherichia coli , Toxinas de Bacillus thuringiensis/metabolismo , Mariposas/genética , Mariposas/metabolismo , Larva/metabolismo , Inseticidas/toxicidade , Inseticidas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/toxicidade , Proteínas Hemolisinas/metabolismo , Bacillus thuringiensis/metabolismo , Resistência a Inseticidas
3.
Bioresour Technol ; : 131287, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153700

RESUMO

Biochar is commonly utilized as an electrode material in supercapacitors. However, the conventional carbonization process often results in macromolecular compounds, which obstruct the porous structure of carbon materials, thereby reducing their capacitance. Dielectric barrier discharge low-temperature plasma (DLTP) is a technology that transforms gases into highly excited states, utilizing high-energy particles for enhanced energy applications. This study investigated the effects of DLTP on the electrochemical performance of bamboo charcoal (BC), utilizing bamboo shavings (BS) as the carbon source. The results indicated that the specific capacitance of BC varied under different atmospheric conditions, input voltages, and treatment durations, thereby achieving a maximum increase of 144 F/g. Furthermore, when combined with KOH activation, DLTP modification further enhanced the specific capacitance of BC to 237 F/g. The DLTP treatment enhanced the specific surface area and the types of functional groups in BC, thereby leading to a significant enhancement of its electrochemical properties.

4.
Psychol Res Behav Manag ; 17: 2807-2818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39082004

RESUMO

Purpose: Numerous empirical studies consistently support the detrimental impact of job insecurity (JI) on employees. However, a new perspective suggests that individuals perceiving JI may proactively take measures to protect their positions. Drawing from the conservation of resources theory, this study argues that perceived resource loss due to JI motivates employees to engage in ingratiating behaviors for expanding their social capital. Additionally, this study empirically establishes the mediating role of emotional exhaustion and the moderating effect of power distance. Methods: A daily diary design was used to examine the relationship between daily JI and next-day ingratiation. Our analyses of data collected from 134 full-time employees across 10 consecutive working days using multi-level model. Results: Our results showed that daily JI was found to affect next-day ingratiation (γ = 0.14, p < 0.01), and this relationship was mediated by emotional exhaustion (indirect effect = 0.07, p < 0.05, 95% CI [0.01, 0.13]). Power distance moderated the relationship between emotional exhaustion and ingratiation (γ = 0.25, p < 0.001), and further moderated the indirect effect of JI on ingratiation via emotional exhaustion. Conclusion: Our study has revealed that JI serves as a catalyst for employees to engage in resource creation behavior, thereby contributing to a deeper understanding of the implications of JI as an independent variable for both scholars and businesses.

5.
Insects ; 15(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38786884

RESUMO

Expressions of a wide range of cytoprotective counter-defense genes are mainly regulated by the Keap1-Nrf2-ARE signaling pathway in response to oxidative stress from xenobiotics. Gossypol is the major antiherbivore secondary metabolite of cotton, but how the polyphagous pest Helicoverpa armigera copes with this phytochemical to utilize its favorite host plant cotton remains largely elusive. In this study, we first suppressed the Keap1 gene in newly hatched larvae of cotton bollworm by feeding them the siRNA diet for 4 days. All of the larvae were subsequently fed the artificial diet supplied with gossypol or the control diet for 5 days. We identified that the knockdown of the Keap1 gene significantly decreased larval mortality and significantly increased the percentages of larval survival, reaching the fourth instar, compared with ncsiRNA when exposed to a diet containing gossypol. Three counter-defense genes CYP9A17, CYP4L11 and UGT41B3, which were related to the induction or metabolism of gossypol according to the report before, were all significantly up-regulated after the knockdown of the Keap1 gene. The Antioxidant Response Elements (AREs) were also detected in the promoter regions of the three counter-defense genes above. These data indicate that the suppression of the Keap1 gene activates the Keap1-Nrf2-ARE signaling pathway, up-regulates the expressions of counter-defense genes involved in the resistance of oxidative stress and finally contributes to reducing the susceptibility of gossypol. Our results provide more knowledge about the transcriptional regulation mechanisms of counter-defense genes that enable the cotton bollworm to adapt to the diversity of host plants including cotton.

6.
Bioresour Technol ; 402: 130756, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688393

RESUMO

DBD low-temperature plasma (DLTP) is recognized as one of the most efficient technologies for treating cotton stalks. This study investigates the impact of various conditions on the gas production characteristics of cotton stalks (CS) and delves into the DLTP decomposition kinetics of CS and CSC in oxygen-enriched (30 % O2/Ar) and CO2 atmospheres. The decomposition rates of CS followed the order CO2 > N2 > Ar. The decomposition behavior of CSC in oxygen-enriched DLTP (30 % O2/Ar) aligned well with the chemical reaction model. The activation energies for CSC decomposition at 900 °C and 1000 °C were determined to be 23.8 kJ/mol and 33.8 kJ/mol, respectively. Moreover, the reaction rate decreased at higher carbonization temperatures, which proved to be detrimental to the decomposition of CSC. The DLTP decomposition of CSC in CO2 exhibited consistency with the fitting results of the unreacted shrinking core model, revealing an observed activation energy of 19.4 kJ/mol.


Assuntos
Gossypium , Gases em Plasma , Gossypium/química , Cinética , Gases em Plasma/química , Dióxido de Carbono/química , Temperatura , Temperatura Baixa , Oxigênio/química
7.
Bioresour Technol ; 399: 130557, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460561

RESUMO

A novel cascade pyrolysis upgrading process for acid hydrolysis lignin (AHL), consisting of pyrolysis, catalytic upgrading of pyrolysis vapors, and pyrolysis char, was developed to improve the yield of value-added products (monophenolic chemicals and carbon materials). Pyrolysis of AHL at 450 °C and subsequent catalytic upgrading of pyrolysis vapors over Ni/H-ZSM-5 boosted the concentration of monophenolic chemicals in pyrolysis liquids by 58%. The carbon material prepared from pyrolysis char using KOH as activating agent exhibited a large specific surface area of 2902.5 m2/g and a large total pore volume of 1.45 cm3/g, thus affording good adsorption capacity for methylene blue (824.87 mg/g) and iodine (2333.17 mg/g). Moreover, the cascade pyrolysis upgrading of AHL achieved a yield of 68.52% desired products, which was much higher than the reported results (single production of monophenols and pyrolysis char). In summary, this work provides a potential reference for efficient utilization of lignin in large-scale applications.


Assuntos
Carbono , Lignina , Pirólise , Adsorção , Hidrólise , Gases , Ácidos
8.
J Agric Food Chem ; 72(33): 18708-18719, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39106049

RESUMO

The extensive use of Bacillus thuringiensis (Bt) in pest management has driven the evolution of pest resistance to Bt toxins, particularly Cry1Ac. Effective management of Bt resistance necessitates a good understanding of which pest proteins interact with Bt toxins. In this study, we screened a Helicoverpa armigera larval midgut cDNA library and captured 208 potential Cry1Ac-interacting proteins. Among these, we further examined the interaction between Cry1Ac and a previously unknown Cry1Ac-interacting protein, HaDALP (H. armigera death-associated LIM-only protein), as well as its role in toxicology. The results revealed that HaDALP specifically binds to both the Cry1Ac protoxin and activated toxin, significantly enhancing cell and larval tolerance to Cry1Ac. Additionally, HaDALP was overexpressed in a Cry1Ac-resistant H. armigera strain. These findings reveal a greater number of Cry1Ac-interacting proteins than previously known and demonstrate, for the first time, that HaDALP reduces Cry1Ac toxicity by sequestering both the protoxin and activated toxin.


Assuntos
Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Endotoxinas , Proteínas Hemolisinas , Proteínas de Insetos , Inseticidas , Larva , Mariposas , Animais , Toxinas de Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/toxicidade , Toxinas de Bacillus thuringiensis/química , Endotoxinas/metabolismo , Endotoxinas/genética , Endotoxinas/toxicidade , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/toxicidade , Proteínas Hemolisinas/genética , Mariposas/metabolismo , Mariposas/efeitos dos fármacos , Mariposas/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/toxicidade , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Larva/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/genética , Inseticidas/toxicidade , Inseticidas/farmacologia , Inseticidas/química , Bacillus thuringiensis/química , Bacillus thuringiensis/metabolismo , Bacillus thuringiensis/genética , Resistência a Inseticidas/genética , Controle Biológico de Vetores , Helicoverpa armigera
9.
Insects ; 15(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38667419

RESUMO

The polyphagous fall armyworm (FAW), Spodoptera frugiperda, has become an invasive pest worldwide in recent years. To develop maize germplasm with multiple pest resistance and understand genetic inheritance, 12 experimental hybrids (six pairs of reciprocal crosses) with diverse genetic backgrounds and four commercial checks were examined for FAW resistance in 2013 and 2014. The experiment utilized a randomized complete block design with four replications as the block factor. FAW injury on maize plants was assessed at 7 and 14 d after the artificial infestation at the V6 stage, and predatory arthropod taxa and abundance on maize seedlings were recorded 7 d after the infestation. Spodoptera frugiperda resistance varied significantly among the 16 hybrids. Two reciprocal crosses ('FAW1430' × 'Oh43' and 'CML333' × 'NC358') showed the least FAW injury. Eleven arthropod predators [i.e., six coleopterans, three hemipterans, earwigs (dermapterans), and spiders (or arachnids)] were also recorded; the two most common predators were the pink spotted ladybeetle, Coleomegilla maculata, and the insidious flower (or minute pirate) bug, Orius spp. Predator abundance was not correlated to FAW injury but varied greatly between 2013 and 2014. Principal component analysis demonstrated that, when compared with FAW resistant (or Bt-transgenic) checks ('DKC69-71', 'DKC67-88', and 'P31P42'), five pairs of the reciprocal crosses had moderate FAW resistance, whereas a pair of reciprocal crosses ('NC350' × 'NC358' and NC358 × NC350) showed the same FAW susceptibility as the non-Bt susceptible check 'DKC69-72'. Both parents contributed similarly to FAW resistance, or no maternal/cytoplasmic effect was detected in the experimental hybrids.

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