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Simple Summary: Spermatogenesis, which is regulated by many different genes, is a conserved process across species to produce mature sperm for animal reproduction. Fox transcription factors can bind to DNA sequences in the promoters to regulate gene expression. FoxD subfamily members are mainly involved in metabolism and early organ development. In Drosophila melanogaster, FoxD subfamily member Fd59a may regulate the development of the nervous system and control the egg-laying behavior of females. However, the functions of insect FoxD members are still largely unknown. In this study, we investigated the role of Fd59a in the spermatogenesis of Drosophila. We found that mutations in Fd59a caused swelling of the apical region in the testis, resulting in fewer mature sperm in the seminal vesicle and significantly lower fertility of Fd59a mutant males compared to the control flies. We also found that the homeostasis of the testis stem cell niche in Fd59a mutant and RNAi flies was disrupted, causing increased apoptosis of sperm bundles. RNA sequencing and qRT-PCR results suggested that Fd59a can regulate the expression of genes related to reproductive process and cell death. Our collective results indicated that Fd59a plays a key role in Drosophila spermatogenesis, which will help to understand the role of FoxD members in insect spermatogenesis. Spermatogenesis is critical for insect reproduction and is regulated by many different genes. In this study, we found that Forkhead transcription factor Fd59a functions as a key factor in the spermatogenesis of Drosophila melanogaster. Fd59a contains a conversed Forkhead domain, and it is clustered to the FoxD subfamily with other FoxD members from some insect and vertebrate species. Mutations in Fd59a caused swelling in the apical region of the testis. More importantly, fewer mature sperm were present in the seminal vesicle of Fd59a mutant flies compared to the control flies, and the fertility of Fd59a2/2 mutant males was significantly lower than that of the control flies. Immunofluorescence staining showed that the homeostasis of the testis stem cell niche in Fd59a2/2 mutant and Fd59a RNAi flies was disrupted and the apoptosis of sperm bundles was increased. Furthermore, results from RNA sequencing and qRT-PCR suggested that Fd59a can regulate the expression of genes related to reproductive process and cell death. Taken together, our results indicated that Fd59a plays a key role in the spermatogenesis of Drosophila. [ABSTRACT FROM AUTHOR]

Spermatogenesis is a critical part of reproduction in insects; however, its molecular mechanism is still largely unknown. In this study, we identified a testis‐specific gene CG3526 in Drosophila melanogaster. Bioinformatics analysis showed that CG3526 contains a zinc binding domain and 2 C2H2 type zinc fingers, and it is clustered to the vertebrate really interesting new gene (RING) family E3 ubiquitin‐protein ligases. When CG3526 was knocked down by RNA interference (RNAi), the testis became much smaller in size, and the apical tip exhibited a sharp and thin end instead of the blunt and round shape in the control testis. More importantly, compared to the control flies, only a few mature sperm were present in the seminal vesicle of C587‐Gal4 > CG3526 RNAi flies. Immunofluorescence staining of the testis from CG3526 RNAi flies showed that the homeostasis of testis stem cell niche was disrupted, cell distribution in the apical tip was scattered, and the process of spermatogenesis was not completed. Furthermore, we found that the phenotype of CG3526 RNAi flies' testis was similar to that of testis of Stat92E RNAi flies, the expression level of CG3526 was significantly downregulated in the Stat92EF06346 mutant flies, and the promoter activity of CG3526 was upregulated by STAT92E. Taken together, our results indicated that CG3526 is a downstream effector gene in the JAK‐STAT signaling pathway that plays a key role in the spermatogenesis of Drosophila. [ABSTRACT FROM AUTHOR]

N6‐methyladenosine (m6A) RNA is the most abundant modification of mRNA, and has been demonstrated in regulating various post‐transcriptional processes. Many studies have shown that m6A methylation plays key roles in sex determination, neuronal functions, and embryonic development in Drosophila and mammals. Here, we analyzed transcriptome‐wide profile of m6A modification in the embryonic development of the destructive agricultural pest Spodoptera frugiperda. We found that the 2 key mRNA m6A methyltransferases SfrMETTL3 and SfrMETTL14 have high homologies with other insects and mammals, suggesting that SfrMETTL3 and SfrMETTL14 may have conserved function among different species. From methylated RNA immunoprecipitation sequencing analysis, we obtained 46 869 m6A peaks representing 8 587 transcripts in the 2‐h embryos after oviposition, and 41 389 m6A peaks representing 9 230 transcripts in the 24‐h embryos. In addition, 5 995 m6A peaks were differentially expressed including 3 752 upregulated and 2243 downregulated peaks. Functional analysis with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes suggested that differentially expressed m6A peak‐modified genes were enriched in cell and organ development between the 2‐ and 24‐h embryos. By conjoint analysis of methylated RNA immunoprecipitation‐seq and RNA‐seq data, we found that RNA m6A methylation may regulate the transcriptional levels of genes related to tissue and organ development from 2‐ to 24‐h embryos. Our study reveals the role of RNA m6A epigenetic regulation in the embryonic development of S. frugiperda, and provides new insights for the embryonic development of insects. [ABSTRACT FROM AUTHOR]

BACKGROUND: Myzus persicae (Hemiptera: Aphididae) is one of the most notorious pests of many crops worldwide. Most Cry toxins produced by Bacillus thuringiensis show very low toxicity to M. persicae; however, a study showed that Cry41‐related toxin had moderate toxic activity against M. persicae. In our previous work, potential Cry41‐related toxin‐binding proteins in M. persicae were identified, including cathepsin B, calcium‐transporting ATPase, and Buchnera‐derived ATP‐dependent 6‐phosphofructokinase (PFKA). Buchnera is an endosymbiont present in almost all aphids and it provides necessary nutrients for aphid growth. This study investigated the role of Buchnera‐derived PFKA in Cry41‐related toxicity against M. persicae. RESULTS: In this study, recombinant PFKA was expressed and purified, and in vitro assays revealed that PFKA bound to Cry41‐related toxin, and Cry41‐related toxin at 25 μg ml−1 significantly inhibited the activity of PFKA. In addition, when M. persicae was treated with 30 μg ml−1 of Cry41‐related toxin for 24 h, the expression of dnak, a single‐copy gene in Buchnera, was significantly decreased, indicating a decrease in the number of Buchnera. CONCLUSION: Our results suggest that Cry41‐related toxin interacts with Buchnera‐derived PFKA to inhibit its enzymatic activity and likely impair cell viability, resulting in a decrease in the number of Buchnera, and finally leading to M. persicae death. These findings open up new perspectives in our understanding of the mode of action of Cry toxins and are useful in helping improve Cry toxicity for aphid control. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Insecticides are anthropogenic environmental stressors and also a common stressor for mosquito vectors. However, the use of insecticides is often guided by short‐term efficacy, and the sublethal effect on their target or nontarget species has long been ignored. Here, we analyzed how sublethal exposure of the promising vector‐control bioinsecticide spinetoram to Aedes aegypti larvae alter adult performance and susceptibility to dengue virus (DENV) infection. We found that the surviving adult mosquitoes were significantly smaller and exhibited weaker blood‐feeding capacity than control females, apart from the extended immature development period. In terms of reproductive potential, although the F0 generation produced a similar number of eggs and offspring during the first gonotrophic cycle, the survival rates of the F1 generations were significantly lower as compared to the control group, suggesting transgenerational sublethal effects on the F1 generation. Notably, surviving adult females had higher DENV‐2 viral loads than the control group after spinetoram sublethal exposure. Mechanistically, transcriptomic analysis showed that inhibition of oxidative phosphorylation may function in stimulating DENV production in adult Ae. aegypti. In Aag2 cells, significant accumulation of apoptosis, mitochondrial reactive oxygen species production, and DENV‐2 replication by spinetoram exposure consistently support our conclusion. Our study highlights the threat of sublethal spinetoram exposure on outbreaks of mosquito‐borne viruses. [ABSTRACT FROM AUTHOR]

20E‐hydroxyecdysone (20E) plays important roles in larval molting and metamorphosis in insects and is also involved in the insect innate immune response. Insect metamorphosis is a highly successful strategy for environmental adaptation and is the most vulnerable stage during which the insect is susceptible to various pathogens. 20E regulates a series of antimicrobial peptides (AMPs) through the immunodeficiency (IMD) pathway activation in Drosophila; nevertheless, whether other immune pathways are involved in 20E‐regulated insect immunity is unknown. Our previous studies showed that BmMD‐2A is a member of the MD‐2‐related lipid recognition (ML) family of proteins that are involved in the Bombyx mori innate immunity Toll signaling pathway. In this study, we further demonstrate that BmMD‐2A is also positively regulated by 20E, and the BmMD‐2A neutralization experiment suggested that 20E activates some downstream immune effect factors, the AMP genes against Escherichia coli and Staphylococcus aureus, through the regulation of BmMD‐2A in larval metamorphosis, implying that B. mori may use the Toll‐ML signaling pathway to maintain innate immune balance in the larval‐pupal metamorphosis stage, which is a different innate immunity pathway regulated by 20E compared to the IMD pathway in Drosophila. [ABSTRACT FROM AUTHOR]

Basic helix‐loop‐helix (bHLH) transcription factors play an important role in a wide range of metabolic and developmental processes in eukaryotes, and bHLH proteins also participate in immune responses, especially in plants. However, their roles in insects upon entomopathogen infection are unknown. In this study, 54 bHLH genes in 41 families were identified in a polyphagous pest, Spodoptera litura, including a new bHLH gene in group B, which is specifically present in Lepidoptera and was thus named Lep. The conserved amino acids in the bHLH domain, structural architecture, and chromosomal distribution of bHLH genes in S. litura were analyzed. The bHLH genes in Plutella xylostella and Apis mellifera were also updated, and genome‐wide comparison and phylogenetic analysis of bHLH members in 5 holometabolous insects were performed. The expression profiles of S. litura bHLH (SlbHLH) genes in 3 tissues at different developmental stages and their responses to S. litura nucleopolyhedrovirus (SpltNPV), Nomuraea rileyi (Nr), and Bacillus thuringiensis (Bt) infection were investigated. More SlbHLHs in group B were expressed and differentially expressed during pathogen infections, and SlbHLHs tended to be downregulated in the midgut of S. litura larvae after B. thuringiensis treatment. Our study provides an overview of bHLH family members in S. litura and their responses to different pathogens used for pest biocontrol. These findings on bHLH members may contribute to uncovering the mechanism of host–pathogen interaction. [ABSTRACT FROM AUTHOR]

Cadherin, aminopeptidase N (APN) and alkaline phosphatase (ALP) have been characterized as Cry receptors. In this study, comparative genomic analysis of the 3 receptor families was performed in 7 insects. ALPs and APNs are divided into three and eight clades in phylogenetic trees, respectively. ALPs in clade 3 and APNs in clade 1 contain multiple paralogs within each species and most paralogs are located closely in chromosomes. Drosophila melanogaster has expanded APNs in clade 5 and were lowly expressed in midgut. Cadherins are divided into 16 clades; they may diverge before holometabolous insect speciation except for BtR and Cad89D‐like clades. Eight insects from different orders containing BtR orthologs are sensitive to Cry1A or Cry3A, while five species without BtR are insensitive to both toxins. Most APNs in clade 1, several ALPs in clade 3, BtR and Cad89D‐like genes were highly or moderately expressed in larval midgut of Spodoptera litura and the other six species, and several members in these clades have been identified as Cry receptors. Expressions of putative S. litura Cry receptors in the midgut after exposing to Bt toxins were also analyzed. [ABSTRACT FROM AUTHOR]

Insect gut microbiota plays important roles in acquiring nutrition, preventing pathogens infection, modulating immune responses, and communicating with environment. Gut microbiota can be affected by external factors such as foods and antibiotics. Spodoptera frugiperda (Lepidoptera: Noctuidae) is an important destructive pest of grain crops worldwide. The function of gut microbiota in S. frugiperda remains to be investigated. In this study, we fed S. frugiperda larvae with artificial diet with antibiotic mixture (penicillin, gentamicin, rifampicin, and streptomycin) to perturb gut microbiota, and then examined the effect of gut microbiota dysbiosis on S. frugiperda gene expression by RNA sequencing. Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria were the most dominant phyla in S. frugiperda. We found that the composition and diversity of gut bacterial community were changed in S. frugiperda after antibiotics treatment. Firmicutes was decreased, and abundance of Enterococcus and Weissella genera was dramatically reduced. Transcriptome analysis showed that 1,394 differentially expressed transcripts (DETs) were found between the control and antibiotics-treated group. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that antibiotics-induced dysbiosis affected many biological processes, such as energy production, metabolism, and the autophagy–lysosome signal pathway. Our results indicated that dysbiosis of gut microbiota by antibiotics exposure affects energy and metabolic homeostasis in S. frugiperda , which help better understand the role of gut microbiota in insects. [ABSTRACT FROM AUTHOR]

A sulfuric acid system was used to recover Co from cobalt white alloy, and the leached cobalt was electrochemically dissolved.i This is a key step to separate the iron-silicon alloy phase from valuable metals when leaching cobalt white alloys with high silicon and iron contents. As an additive, sodium hypochlorite (NaClO) acts as an oxidant to break cobalt encapsulation and enhances leaching. It generates chloride ions, which further enhance Co leaching based on their corrosive ability. The results showed that the maximum leaching ratio of Co from the waste cobalt white alloy was 97.76%. Kinetic analysis showed that the apparent activation energy of Co leaching was 34.58 kJ/mol, and the surface chemical reaction was a controlling step for this process. The kinetic equation for the leaching of Co can be expressed as 1 - 1 - α 1 3 = 0.065 t × r 0 - 1 × H 2 SO 4 2.44 × exp - 34580 8.314 T . [ABSTRACT FROM AUTHOR]

Wolbachia are Gram‐negative endosymbionts that are known to cause embryonic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia, a situation characterized as cytoplasmic incompatibility (CI). However, the mechanism of CI is not yet fully understood, although recent studies on Drosophila melanogaster have achieved great progress. Here, we found that Wolbachia infection caused changes in the expressions of several immunity‐related genes, including significant upregulation of kenny (key), in the testes of D. melanogaster. Overexpression of key in fly testes led to a significant decrease in egg hatch rates when these flies mate with wild‐type females. Wolbachia‐infected females could rescue this embryonic lethality. Furthermore, in key overexpressing testes terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick‐end labeling signal was significantly stronger than in the control testes, and the level of reactive oxygen species was significantly increased. Overexpression of key also resulted in alterations of some other immunity‐related gene expressions, including the downregulation of Zn72D. Knockdown of Zn72D in fly testes also led to a significant decrease in egg hatch rates. These results suggest that Wolbachia might induce the defect in male host fertility by immunity‐related pathways and thus cause an oxidative damage and cell death in male testes. [ABSTRACT FROM AUTHOR]

Introduction: Lung cancer is the leading cause of cancer-associated mortality worldwide. Recently, long non-coding RNAs (lncRNAs) have been studied as key regulators in some biological processes. Of note, the molecular mechanism and prognostic value of lncRNAs in non-small cell lung cancer (NSCLC) have largely remained unclear.Material and Methods: In this study, we compared the PTTG3P expression levels between lung cancer and normal lung samples by analyzing 5 public datasets (GSE18842, GSE19804, GSE27262, GSE30219, and GSE19188). Next, pentose phosphate pathway and co-expression networks were constructed to identify key targets of lncRNA PTTG3P. Furthermore, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to explore the potential roles of lncRNA PTTG3P. Moreover, we constructed PTTG3P-mediated ceRNA networks in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC).Results: In the present study, our analysis showed that PTTG3P expression was higher in high T stage LUAD and LUSC samples, as well as high N stage NSCLC tissues. Of note, we found that higher PTTG3P expression is correlated with shorter survival time in NSCLC patients by analyzing Kaplan-Meier plotter datasets. We found that PTTG3P was significantly associated with NSCLC cell proliferation regulation by affecting a series of cell cycle related biological processes.Conclusions: Bioinformatics analysis showed that PTTG3P was associated with NSCLC cell proliferation. These results suggested that PTTG3P could serve as a new therapeutic and prognostic target for NSCLC. [ABSTRACT FROM AUTHOR]

The unique structure and physicochemical properties of insect intestines provide suitable conditions for colonization by various microorganisms, the community composition of which is closely related to the growth, development, metabolism, reproduction and other life activities, of their insect hosts. Insects have an abundant and diverse gut microflora. The relatively stable symbiotic relationships between insects and their gut microflora play an extremely important role in the insect life cycle. Gut microbiota not only provide important nutrients for their insect hosts but also assist in the digestion of food, immune defense and detoxification. They also affect the life span, development, mating and reproductive capacity of insects. Insect gut microbes can potentially be utilized in many fields, including agriculture, ecology, medicine, energy and environmental protection. This paper reviews recent progress in research on insect gut microbiota, including its diversity, function, factors that affect it and its potential utilization. [ABSTRACT FROM AUTHOR]

The innate immune system plays a critical role in the ability of insects to adapt to changing environments, and its underlying mechanism has become a new area of research in pest control. The insect innate immune system is comprised of humoral immunity and cellular immunity, and involves many proteins and molecules. Research on the innate immune system of insects has advanced greatly in recent years, mainly due to research on the fruit fly Drosophila melanogaster. D. melanogaster is an ideal model organism for studying innate immunity due to its clear genetic background and many available manipulation tools. Pattern recognition receptors (PRRs), antimicrobial peptides (AMPs) and immune signaling pathways have been well investigated in Drosophila. In this mini-review, we summarize recent advances in research on the innate immune system of Drosophila over the last 20 years. We hope that this review will inspire the study of the innate immune mechanisms of other insect species and provide a theoretical basis for pest control. [ABSTRACT FROM AUTHOR]

Background: Bacillus thuringiensis israelensis (Bti) is a widely used mosquitocidal microbial pesticide due to its high toxicity. ATP-binding proteins (ABP) are prevalently detected in insects and are related to reaction against Bti toxins. However, the function of ABP in mosquito biocontrol is little known, especially in Aedes aegypti. Therefore, this study aimed to clarify the function of ABP in Ae. aegypti against Bti toxin. Results: Aedes aegypti ABP (GenBank: XM_001661856.2) was cloned, expressed and purified in this study. Far-western blotting and ELISA were also carried out to confirm the interaction between ABP and Cry11Aa. A bioassay of Cry11Aa was performed both in the presence and absence of ABP, which showed that the mortality of Ae. aegypti is increased with an increase in ABP. Conclusions: Our results suggest that ABP in Ae. aegypti can modulate the toxicity of Cry11Aa toxin to mosquitoes by binding to Bti toxin. This could not only enrich the mechanism of Bt toxin, but also provide more data for the biocontrol of this transmission vector. [ABSTRACT FROM AUTHOR]

To improve the processing efficiency on batch query for MapReduce, a multiple query optimization approach based on Hive+ is proposed to reduce the number of MapReduce tasks on multiple query, decrease the start time of MapReduce task and the overhead of fault tolerance, improve the query efficiency. TPC-H benchmark test set is selected as the use cases to experiment on Hive-0.12. The experiment shows that the processing efficiency of batch query is effectively improved. [ABSTRACT FROM AUTHOR]

Livestock on the Qinghai-Tibetan Plateau are faced with extreme harsh winters and are often in negative energy balance during this period. Dietary supplementation can improve growth performance of Tibetan sheep and, consequently, we hypothesized that it would also increase microbial abundance and rumen epithelium development. To test this hypothesis, we examined the effect of feed supplementation during the cold season on rumen microbes, fermentation, epithelium development, and absorptive capability in Tibetan sheep. Eighteen 1-yr-old ewes (BW = 29.4 ± 1.79, kg) were offered oat hay ad libitum for 60 d and divided randomly into three groups: 1) no supplement; control group (CON); 2) urea-molasses lick block supplement (BS); and 3) concentrate feed supplement (CS). The ADG of CS ewes (143.3, g/d) was greater (P < 0.05) than BS ewes (87.9, g/d), which was greater (P < 0.05) than CON ewes (44.5, g/d). Serum concentrations of GH, IGF-1, and IGF-2 in the CS and BS groups were greater than in the CON group (P < 0.05). Greater relative abundance of protozoa, Ruminococcus albus, Fibrobacter succinogenes, Streptococcus bovis, and Ruminobacter amylophilus was observed in the CS and BS groups than in the CON group (P < 0.05), and relative abundances of rumen fungi, Butyrivibrio fibrisolvens, and Prevotella ruminicola in the CS group were greater than in the BS and CON groups (P < 0.05). Ruminal total VFA, ammonia, and microbial protein concentrations in the CS and BS groups were greater than in the CON group (P < 0.05), and in the CS group were greater than in the BS group (P < 0.05). Ruminal papillae width and surface area in the CS and BS groups were greater than in the CON group (P < 0.05), while in the CS group were greater than in the BS group (P < 0.05). The mRNA expressions of IGFBP5, NHE1 (sodium/hydrogen antiporter, isoform 1), DRA (downregulated in adenoma), and Na+/K+-ATPase (sodium/potassium ATPase pump) in ruminal epithelium were greater in the CS and BS groups than in the CON group (P < 0.05), and in the CS group was greater than in the BS group (P < 0.05), while NHE3 (sodium/hydrogen antiporter, isoform 3), MCT1 (monocarboxylate transporter 1), and MCT4 (monocarboxylate transporter 4) mRNA expressions in the CS group were greater than in the BS and CON groups (P < 0.05). It was concluded that supplementing Tibetan sheep during the cold season increases rumen microbial abundance and improves fermentation parameters, rumen epithelium development, and absorptive capability. [ABSTRACT FROM AUTHOR]

Insects are one of the major sources of antimicrobial peptides/proteins (AMPs). Since observation of antimicrobial activity in the hemolymph of pupae from the giant silk moths Samia Cynthia and Hyalophora cecropia in 1974 and purification of first insect AMP (cecropin) from H. cecropia pupae in 1980, over 150 insect AMPs have been purified or identified. Most insect AMPs are small and cationic, and they show activities against bacteria and/or fungi, as well as some parasites and viruses. Insect AMPs can be classified into four families based on their structures or unique sequences: the α-helical peptides (cecropin and moricin), cysteine-rich peptides (insect defensin and drosomycin), proline-rich peptides (apidaecin, drosocin, and lebocin), and glycine-rich peptides/proteins (attacin and gloverin). Among insect AMPs, defensins, cecropins, proline-rich peptides, and attacins are common, while gloverins and moricins have been identified only in Lepidoptera. Most active AMPs are small peptides of 20-50 residues, which are generated from larger inactive precursor proteins or pro-proteins, but gloverins (~14 kDa) and attacins (~20 kDa) are large antimicrobial proteins. In this mini-review, we will discuss current knowledge and recent progress in several classes of insect AMPs, including insect defensins, cecropins, attacins, lebocins and other proline-rich peptides, gloverins, and moricins, with a focus on structural-functional relationships and their potential applications. [ABSTRACT FROM AUTHOR]

Destruxins, cyclohexadepsipeptidic mycotoxins isolated from the entomopathogenic fungus Metarhizium anisopliae, inhibit innate insect immunity. However, their mechanism of action remains unclear. In this study, the effects of destruxins on changes in free calcium and hydrogen ions in the hemocytes of Exolontha serrulata, Bombyx mori and the Spodoptera litura SL-1 cell line were detected using laser scanning confocal microscopy (LSCM). An instant Ca2+ influx of hemocytes induced by destruxins A and B (DA and DB) was recorded. The DA/DB-dependent Ca2+ influx was not influenced by the Ca2+ channel inhibitors 2-aminoethoxydiphenyl borane (2-APB) and U73122. It also had an apparently different LSCM profile from that of the ionomycin-dependent Ca2+ influx. However, the instant Ca2+ influx was not seen in the SL-1 cells; on the contrary, a slow, moderate enhancement of intracellular Ca2+ was observed. Meanwhile, an instant intracellular free H+ decrease aroused by DA and DB was found. DB at 20 μmol/L and DA at 690 μmol/L significantly reduced intracellular free H+ levels. Furthermore, the vacuolar H+-ATPase (V-ATPase) inhibitor bafilomycin A1 had obvious effects on the decreases of intracellular free H+ in hemocytes. These results suggest that the mechanism of DA/DB-dependent Ca2+ influx is perhaps not related to Ca2+ channels and ionophores; rather, the intracellular free H+ decrease might be due to V-ATPase inhibition. [ABSTRACT FROM AUTHOR]

Giant resonance enhancement is demonstrated to be due to the Fano interference in a grating waveguide composed of gain-assisted silicon slabs. The Fano mode is characterized by its ultra-narrow asymmetric spectrum, different from that of a pure electric or magnetic dipole. The simulation indicates that a sharp Fano-interfered lineshape is responsible for the giant resonance enhancement featuring the small-gain requirements. [ABSTRACT FROM AUTHOR]

The Toll-like receptor (TLR)-mediated NF-κB pathway is tightly controlled because overactivation may result in severe damage to the host, such as in the case of chronic inflammatory diseases and cancer. In mammals, sterile-alpha and armadillo motif-containing protein (SARM) plays an important role in negatively regulating this pathway. While Caenorhabditis elegans SARM is crucial for an efficient immune response against bacterial and fungal infections, it is still unknown whether Drosophila SARM participates in immune responses. Here, Litopenaeus vannamei SARM (LvSARM) was cloned and functionally characterized. LvSARM shared signature domains with and exhibited significant similarities to mammalian SARM. Real-time quantitative PCR analysis indicated that the expression of LvSARM was responsive to Vibrio alginolyticus and white spot syndrome virus (WSSV) infections in the hemocyte, gill, hepatopancreas and intestine. In Drosophila S2 cells, LvSARM was widely distributed in the cytoplasm and could significantly inhibit the promoters of the NF-κB pathway-controlled antimicrobial peptide genes (AMPs). Silencing of LvSARM using dsRNA-mediated RNA interference increased the expression levels of Penaeidins and antilipopolysaccharide factors, which are L.vannamei AMPs, and increased the mortality rate after V. alginolyticus infection. Taken together, our results reveal that LvSARM may be a novel component of the shrimp Toll pathway that negatively regulates shrimp AMPs, particularly Penaeidins and antilipopolysaccharide factors. [ABSTRACT FROM AUTHOR]

A new phosphorescent dinuclear cationic iridium(III) complex ( Ir1) with a donor-acceptor-π-bridge-acceptor-donor (DAπAD)-conjugated oligomer ( L1) as a N^N ligand and a triarylboron compound as a C^N ligand has been synthesized. The photophysical and excited-state properties of Ir1 and L1 were investigated by UV/Vis absorption spectroscopy, photoluminescence spectroscopy, and molecular-orbital calculations, and they were compared with those of the mononuclear iridium(III) complex [Ir(Bpq)2(bpy)]+PF6− ( Ir0). Compared with Ir0, complex Ir1 shows a more-intense optical-absorption capability, especially in the visible-light region. For example, complex Ir1 shows an intense absorption band that is centered at λ=448 nm with a molar extinction coefficient ( ε) of about 104, which is rarely observed for iridium(III) complexes. Complex Ir1 displays highly efficient orange-red phosphorescent emission with an emission wavelength of 606 nm and a quantum efficiency of 0.13 at room temperature. We also investigated the two-photon-absorption properties of complexes Ir0, Ir1, and L1. The free ligand ( L1) has a relatively small two-photon absorption cross-section ( δmax=195 GM), but, when complexed with iridium(III) to afford dinuclear complex Ir1, it exhibits a higher two-photon-absorption cross-section than ligand L1 in the near-infrared region and an intense two-photon-excited phosphorescent emission. The maximum two-photon-absorption cross-section of Ir1 is 481 GM, which is also significantly larger than that of Ir0. In addition, because the strong BF interaction between the dimesitylboryl groups and F− ions interrupts the extended π-conjugation, complex Ir1 can be used as an excellent one- and two-photon-excited 'ON-OFF' phosphorescent probe for F− ions. [ABSTRACT FROM AUTHOR]

A scheme for generating the giant enhancement of the Kerr nonlinearity in a four-level system with the quantum coherences from the decays and the incoherent pumping is proposed. Compared with that generated in a general four-level system, the Kerr nonlinearity can be enhanced by several orders of magnitude with vanishing linear absorption. By using the numerical results, we show that the remarkable enhancement should be attributed to the interaction of the quantum coherences from the decays and the incoherent pumping. [ABSTRACT FROM AUTHOR]

Our previous research showed that immulectin-2 (IML-2), a C-type lectin from the tobacco hornworn, Manduca sexta, is a pattern recognition receptor (PRR) that can bind to pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS), peptidoglycan (PG) and β-1,3-glucan, and IML-2 plays an important role in cellular encapsulation, melanization, phagocytosis, and prophenoloxidase (proPO) activation. Unlike most mammalian C-type lectins that contain a single carbohydrate-recognition domain (CRD), IML-2 is composed of tandem CRDs, and the C-terminal CRD2 contains an extended loop, which is not present in most C-type CRDs. We hypothesize that the extended loop may participate in ligand binding, encapsulation, melanization, phagocytosis and/or proPO activation in M. sexta. To test this hypothesis, two deletion mutant proteins (IML-2 and IML-2), in which the extended loop of the CRD2 was partially or completely deleted, were expressed and purified. By comparing the characteristics of recombinant IML-2, IML-2 and IML-2, we found that deletion of the extended loop in CRD2 impaired the ability of IML-2 to bind microbial PAMPs and to stimulate proPO activation, indicating that the extended loop of IML-2 plays an important role in ligand binding and biological functions. [ABSTRACT FROM AUTHOR]

The present study focuses on a series of carbazole derivatives, which are being investigated as potential two-photon fluorescent probes (TFP) for DNA detection and two-photon bioimaging. The geometric structures, electronic structures, and the one-photon (OPA) and two-photon (TPA) absorption properties of 3,6-bis(1-methyl-4-vinylpyridinium) carbazole (BMVC) derivatives, as well as their dications and diiodized derivatives, were studied using density functional theory (DFT) and Zerner's intermediate neglect of differential overlap (ZINDO) method. The results showed that the TPA spectra of the diiodized BMVC derivatives and their dications are all found in the near-infrared region (NIR). At the same time, the diiodized BMVC derivatives presented larger TPA cross-sections than the neutral BMVC derivatives and the dications. These theoretically derived values were also in good agreement with their corresponding experimentally observed values, and they indicated that the diiodized BMVC may be the form of this TFP that combines with DNA. The diiodized BMVC derivatives and the dications have the potential to be excellent TPA materials, especially when used as TFPs in nucleic acid imaging applications. [ABSTRACT FROM AUTHOR]

First we present a theoretical analysis of classical noise in ghost imaging system based on the coherent-mode representation theory. The classical noise depends crucially on the distribution of the eigenvalues of the coherent-mode representation of the source and the decomposition coefficients of the object imaged. We show that both decreasing the distribution of the decomposition coefficients and increasing the distribution of the eigenvalues can lead to the decrease of classical noise. [ABSTRACT FROM AUTHOR]

A novel two-photon absorption (TPA) material with phenanthrolin as acceptor (BSIPB) has been firstly synthesized and studied as possible fluorescence probe for nucleic acids detection. The single-photon and two-photon fluorescence properties of the dye in the unbound state and in DNA complexes were investigated. Some quantum yields and TPA cross sections at important points were calculated. The results showed that BSIPB can be used as an efficient fluorescent probes for DNA detection and imaging under both single-photon excitation (SPE) and two-photon excitation (TPE). [ABSTRACT FROM AUTHOR]

Hemolin, a plasma protein from lepidopteran insects, is composed of four immunoglobulin domains. Its synthesis is induced by microbial challenge. We investigated the biological functions of hemolin in Manduca sexta. It was found to bind to the surface of bacteria and yeast, and caused these micro-organisms to aggregate. Hemolin was demonstrated to bind to lipopolysaccharide (LPS) from Gram-negative bacteria and to lipoteichoic acid from Gram-positive bacteria. Binding of hemolin to smooth-type forms of LPS was competed for efficiently by lipoteichoic acid and by rough mutant (Ra and Rc) forms of LPS, which differ in polysaccharide length. Binding of hemolin to LPS was partially inhibited by calcium and phosphate. Hemolin bound to the lipid A component of LPS, and this binding was completely blocked by free phosphate. Our results suggest that hemolin has two binding sites for LPS, one that interacts with the phosphate groups of lipid A and one that interacts with the O-specific antigen and the outer-core carbohydrates of LPS. The binding properties of M. sexta hemolin suggest that it functions as a pattern-recognition protein with broad specificity in the defense against micro-organisms. [ABSTRACT FROM AUTHOR]

Abstract: The series of stereotypical physiological and behavioral changes that female insects exhibit after mating are called postmating responses (PMR). Wolbachia are widespread intracellular bacteria that are well known for their ability to manipulate the host’s reproductive behavior to facilitate their own maternal spreading. The effect of Wolbachia infection on insect hosts’ PMR is not well understood. Here, we showed that after mating with male Drosophila melanogaster infected with Wolbachia, the uninfected female showed a significant decrease in egg laying on the first day. Furthermore, both Wolbachia-infected and Wolbachia-uninfected females mated with infected males exhibited reduced feeding frequency, low receptivity to remating, and an extended median life span compared to those mated with uninfected males. To determine how Wolbachia triggered these alterations, we detected the influence of Wolbachia infection on the expression of some genes encoding seminal fluid proteins (Sfps) in D. melanogaster. These seminal fluid proteins are known to contribute to PMR upon transfer to females during copulation. We found that Acp26Aa, CG1656, and CG42474 were significantly downregulated in Wolbachia-infected males, whereas SP, CG1652, CG9997, and CG17575 showed no significant difference between Wolbachia-infected and Wolbachia-uninfected males. These results suggest that by decreasing the expression of some Sfps in the male hosts, Wolbachia may modulate sexual conflicts of their insect hosts in a way favoring females, thus benefit their own transmission through host populations. This study provides new insights into the host-endosymbiont interaction, which may support the application of endosymbionts for the control of pests and disease vectors.Significance statement: Wolbachia are among the most successful intracellular bacteria that can infect many insect species as well as filarial nematodes. Wolbachia infect host reproductive tissues and are best known for manipulating host reproductive systems to enhance their transmission through host populations. Mating may result in many physiological and behavioral changes in female insects, which are called postmating responses (PMR). Here, we found that after mating with Wolbachia-infected males, Drosophila melanogaster females showed altered PMR, including decreased feeding frequency, attenuated propensity to remating, and prolonged median survival, when compared to those mated with uninfected males. This could be due to a reduction of seminal fluid proteins induced by Wolbachia infection. These findings may raise new speculation about bacteria-host interactions and the ecological and evolutionary consequences of parasitic infection. [ABSTRACT FROM AUTHOR]

Apoptosis plays an important role in white spot syndrome virus (WSSV) pathogenesis, and caspases are central players in apoptosis. Here, we cloned four novel caspases (Lvcaspase2-5) from the Pacific white shrimp Litopenaeus vannamei, and investigated their potential roles in WSSV replication using dsRNA-mediated gene silencing. Lvcaspase2-5 have the typical domain structure of caspase family proteins, with the conserved consensus motifs p20 and p10. Lvcaspase2 and Lvcaspase5 were highly expressed in muscle, while Lvcaspase3 was highly expressed in hemocytes and Lvcaspase4 was mainly expressed in intestine. Lvcaspase2-5 could also be upregulated by WSSV infection, and they showed different patterns in various tissues. When overexpressed in Drosophila S2 cells, Lvcaspase2-5 showed different cellular localizations. Using dsRNA-medicated gene silencing, the expression of Lvcaspase2, Lvcaspase3, and Lvcaspase5 were effectively knocked down. In Lvcaspase2-, Lvcaspase3- or Lvcaspase5-silenced L. vannamei, expression of WSSV VP28 gene was significantly enhanced, suggesting protective roles for Lvcaspase2, Lvcaspase3 and Lvcaspase5 in the host defense against WSSV infection. [ABSTRACT FROM AUTHOR]

Inhibitors of apoptosis (IAPs) play important roles in apoptosis and NF-κB activation. In this study, we cloned and characterized three IAPs (LvIAP1-3) from the Pacific white shrimp, Litopenaeus vannamei. LvIAP1-3 proteins shared signature domains and exhibited significant similarities with other IAP family proteins. The tissue distributions of LvIAP1-3 were studied. The expression of LvIAP1-3 was induced in the muscle after white spot syndrome virus (WSSV) infection. LvIAP1 expression in the gill, hemocytes, hepatopancreas, and intestine was responsive to WSSV and Vibrio alginolyticus infections. LvIAP2 expression in the gill, hemocytes, and hepatopancreas was also responsive to WSSV infection. The expression of LvIAP3 in the gill, hemocytes, and intestine was reduced after V. alginolyticus infection. When overexpressed in Drosophila S2 cells, GFP labeled-LvIAP2 was distributed in the cytoplasm and appeared as speck-like aggregates in the nucleus. Both LvIAP1 and LvIAP3 were widely distributed throughout the cytoplasm and nucleus. The expression of LvIAP1, LvIAP2, and LvIAP3 was significantly knocked down by dsRNA-mediated gene silencing. In the gill of LvIAP1- or LvIAP3-silenced shrimp, the expression of WSSV VP28 was significantly higher than that of the dsGFP control group, suggesting that LvIAP1 and LvIAP3 may play protective roles in host defense against WSSV infection. Intriguingly, the LvIAP2-silenced shrimp all died within 48 hours after dsLvIAP2 injection. In the hemocytes of LvIAP2-silenced shrimps, the expression of antimicrobial peptide genes (AMPs), including Penaeidins, lysozyme, crustins, Vibrio penaeicidae-induced cysteine and proline-rich peptides (VICPs), was significantly downregulated, while the expression of anti-lipopolysaccharide factors (ALFs) was upregulated. Moreover, LvIAP2 activated the promoters of the NF-κB pathway-controlled AMPs, such as shrimp Penaeidins and Drosophila drosomycin and attacin A, in Drosophila S2 cells. Taken together, these results reveal that LvIAP1 and LvIAP3 might participate in the host defense against WSSV infection, and LvIAP2 might be involved in the regulation of shrimp AMPs. [ABSTRACT FROM AUTHOR]