Dermatophagoides farinae microRNAs released to external environments via exosomes regulate inflammation-related gene expression in human bronchial epithelial cells.

Background: Dermatophagoides farinae (DFA) is an important species of house dust mites (HDMs) that causes allergic diseases. Previous studies have focused on allergens with protein components to explain the allergic effect of HDMs; however, there is little knowledge on the role of microRNAs (miRNAs) in the allergic effect of HDMs. This study aimed to unravel the new mechanism of dust mite sensitization from the perspective of cross-species transport of extracellular vesicles-encapsulated miRNAs from HDMs. Methods: Small RNA (sRNA) sequencing was performed to detect miRNAs expression profiles from DFA, DFA-derived exosomes and DFA culture supernatants. A quantitative fluorescent real-time PCR (qPCR) assay was used to detect miRNAs expression in dust specimens. BEAS-2B cells endocytosed exosomes were modeled in vitro to detect miRNAs from DFA and the expression of related inflammatory factors. Representative dfa-miR-276-3p and dfa-novel-miR2 were transfected into BEAS-2B cells, and then differentially expressed genes (DEGs) were analyzed by RNA sequencing. Protein-protein interaction (PPI) network analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment analyses were performed on the first 300 nodes of DEGs. Results: sRNA sequencing identified 42 conserved miRNAs and 66 novel miRNAs in DFA, DFA-derived exosomes, and DFA culture supernatants. A homology analysis was performed on the top 18 conserved miRNAs with high expression levels. The presence of dust mites and miRNAs from HDMs in living environment were also validated. Following uptake of DFA-derived exosomes by BEAS-2B cells, exosomes transported miRNAs from DFA to target cells and produced pro-inflammatory effects in corresponding cells. RNA sequencing identified DEGs in dfa-miR-276-3p and dfa-novel-miR2 transfected BEAS-2B cells. GO and KEGG enrichment analyses revealed the role of exosomes with cross-species transporting of DFA miRNAs in inflammatory signaling pathways, such as JAK-STAT signaling pathway, PI3K/AKT signaling pathway and IL-6-mediated signaling pathway. Conclusion: Our findings demonstrate the miRNAs expression profiles in DFA for the first time. The DFA miRNAs are delivered into living environments via exosomes, and engulfed by human bronchial epithelial cells, and cross-species regulation may contribute to inflammation-related processes.

Exosomes Derived from Dermatophagoides farinae Induce Allergic Airway Inflammation.

House dust mites (HDMs) are a major source of indoor allergens that cause airway allergic disease. Dermatophagoides farinae, a predominant species of HDMs in China, has demonstrated pathogenic role in allergic disorders. Exosomes derived from human bronchoalveolar lavage fluid have been strongly associated with allergic respiratory diseases progression. However, the pathogenic role of D. farinae-derived exosomes in allergic airway inflammation has remained unclear until now. Here, D. farinae was stirred overnight in phosphate-buffered saline, and the supernatant was used to extract exosomes by ultracentrifugation. Then, shotgun liquid chromatography-tandem mass spectrometry and small RNA sequencing were performed to identify proteins and microRNAs contained in D. farinae exosomes. Immunoblotting, Western blotting, and enzyme-linked immunosorbent assay demonstrated the specific immunoreactivity of D. farinae-specific serum IgE antibody against D. farinae exosomes, and D. farinae exosomes were found to induce allergic airway inflammation in a mouse model. In addition, D. farinae exosomes invaded 16-HBE bronchial epithelial cells and NR8383 alveolar macrophages to release the inflammation-related cytokines interleukin-33 (IL-33), thymic stromal lymphopoietin, tumor necrosis factor alpha, and IL-6, and comparative transcriptomic analysis of 16-HBE and NR8383 cells revealed that immune pathways and immune cytokines/chemokines were involved in the sensitization of D. farinae exosomes. Taken together, our data demonstrate that D. farinae exosomes are immunogenic and may induce allergic airway inflammation via bronchial epithelial cells and alveolar macrophages. IMPORTANCE Dermatophagoides farinae, a predominant species of house dust mites in China, has displayed pathogenic role in allergic disorders, and exosomes derived from human bronchoalveolar lavage fluid have been strongly associated with allergic respiratory diseases progression. However, the pathogenic role of D. farinae-derived exosomes in allergic airway inflammation has remained unclear until now. This study, for the first time, extracted exosomes from D. farinae, and sequenced their protein cargo and microRNAs using shotgun liquid chromatography-tandem mass spectrometry and small RNA sequencing. D. farinae-derived exosomes trigger allergen-specific immune responses and present satisfactory immunogenicity, as revealed by immunoblotting, Western blotting, and enzyme-linked immunosorbent assay and may induce allergic airway inflammation via bronchial epithelial cells and alveolar macrophages. Our data provide insights into the mechanisms of allergic airway inflammation caused with D. farinae-derived exosomes and the treatment of house dust mite-induced allergic airway inflammation.

NOD1 mediated D. pteronyssinus-induced allergic airway inflammation through RIP2/NF-κB.

BACKGROUND: Dermatophagoides pteronyssinus (D. pteronyssinus) is the main cause of allergic airway inflammation. As the earliest intracytoplasmic pathogen recognition receptors (PRR), NOD1 has been identified as key inflammatory mediator in NOD-like receptor (NLR) family. OBJECTIVE: Our primary aim is to elucidate whether NOD1 and its downstream regulatory proteins mediate D. pteronyssinus-induced allergic airway inflammation. METHODS: Mouse and cell models of D. pteronyssinus-induced allergic airway inflammation were established. NOD1 was inhibited in bronchial epithelium cells (BEAS-2B cells) and mice by cell transfection or application of inhibitor. The change of downstream regulatory proteins was detected by quantitative real-time PCR (qRT-PCR) and Western blot. The relative expression of inflammatory cytokines was evaluated by ELISA. RESULTS: The expression level of NOD1 and its downstream regulatory proteins increased in BEAS-2B cells and mice after treating with D. pteronyssinus extract, followed by the aggravation of inflammatory response. Moreover, inhibition of NOD1 decreased the inflammatory response, which also downregulated the expression of downstream regulatory proteins and inflammatory cytokines. CONCLUSIONS: NOD1 involves in the development of D. pteronyssinus-induced allergic airway inflammation. Inhibition of NOD1 reduces D. pteronyssinus-induced airway inflammation.

miR-142-3p alleviates house dust mite induced airway inflammation among children / 中国学校卫生

Objective@#To investigate the role of miR-142-3p in alleviation of house dust mite induced allergic airway inflammation among children, so as to provide insights into unraveling the pathogenesis of allergic airway inflammation.@*Methods@#Serum samples were collected from 15 patients with house dust mite induced allergic asthma and 15 healthy children in Jiangnan University Medical Center from September to November 2022, and serum miR-142-3p expression was quantified using a fluorescent quantitative real time PCR (qPCR) assay. The levels of interleukin 6 (IL 6) and tumor necrosis factor α (TNF α) were measured in the cell culture supernatant using enzyme linked immunosorbent assay (ELISA), and the expression of high mobility group box 1 (HMGB1) was detected at transcriptional and translational lvels using qPCR and Western blotting assays. The negative regulation of the HMGB1 gene by miR 142 3p was identified using a dual luciferase gene reporter assay, and the expression of downstream regulatory proteins was determined in human normal lung epithelial cells (BEAS 2B) cells transfected with miR 142 3p using Western blotting. In addition, female C57BL/6 mice at ages of 6-8 weeks were randomly assigned to the phosphate buffer saline (PBS) group, house dust mite sensitized airway inflammation group and house dust mite sensitized airway inflammation + miR 142 3p intervention group. Mouse airway inflammation was evaluated using hematoxylin eosin staining, and the expression of inflammatory cells and inflammatory cytokines were detected in mouse bronchoalveolar lavage fluid (BALF) using Giemsa staining and ELISA.@*Results@#Lower serum miR-142-3p expression was quantified among children with house dust mite induced allergic asthma than among healthy controls (1.33±0.21 vs. 4.74±0.62, t=5.22, P <0.05). Stimulation with dermatophagoides farinae extract (DFE) resulted in a reduction in miR-142-3p expression in BEAS-2B cells (0.82±0.25), while transfection with miR-142-3p mimics resulted in a rise in miR-142-3p expression in BEAS-2B cells (0.55±0.14)( t=3.31, 3.94, P <0.05). Pre treatment with miR-142-3p reduced the expression of IL 6(2.25±0.46)and TNF α(6.58±1.95) ( t=4.86, 3.38, P <0.05) in BEAS 2B cells stimulated with DFE, and treatment with miR-142-3p mimics resulted in a reduction in TLR4 and NF-κB expression in BEAS-2B cells via negative regulation of the HMGB1 expression. In addition, treatment with miR-142-3p was found to alleviate inflammatory cell infiltration in lung tissues of house dust mite sensitized mice, and results in a reduction in interleukin 4 (IL-4)[(107.60±10.43)pg/mL], interleukin 5 (IL 5)[(95.78±13.14)pg/mL] and HMGB1[(2.52±0.87)pg/mL] expression in BALF ( t=10.32, 7.29, 2.90, P <0.05).@*Conclusion@#miR-142-3p alleviates house dust mite induced allergic airway inflammation among children via negative regulation of the HMGB1/TLR4/NF-κB pathway.

A rapid and quantitative detection method for plasma soluble growth stimulating gene protein 2 based on time resolved fluorescence immunochromatography.

Background: plasma soluble growth stimulating gene protein 2 (sST2) is a new generation biomarker in heart failure (HF), which is an independent predictor of adverse outcomes of heart failure. Thus, the establishment of a rapid and sensitive method for detecting sST2 is urgently needed. Methods: lanthanide element Eu3+ coated fluorescent nanometer microspheres (Eu3+@FMN) can be used as markers to label monoclonal mouse anti-human sST2 antibody ST-01 (ST-01-Eu3+@FMN). When the immune sandwich complex formed between the monoclonal mouse anti-human sST2 antibody ST-02 and ST-01-Eu3+@FMN on the test band with the appearance of target object sST2, we can detect the fluorescence intensity of Eu3+ on the test band and the quality control band using a dry fluorescence analyzer. We calculated the T/C value (T/C = fluorescence intensity of the test band/fluorescence intensity of the quality control band), fitted to the calibration curve, and measured the concentration value of sST2 in the corresponding sample. Results: the best reaction time was 15 min after condition exploration, and the optimal sample volume was 80 µL. The detection sensitivity of the scheme was 2.14 ng mL-1. The calibration curve of the assay was y = 0.0113x + 0.0033, and the linear range was 5-200 ng mL-1. No cross reaction was found when the samples contained BNP, NT-proBNP, and galectin-3, indicating a good specificity. The precision was good with a relative deviation < 15%. The coefficient of variation of detection results of low-concentration samples and high-concentration samples was 4.20% and 3.30% respectively in the same batch of strip tests, so the intra-assay CV was set as <10%; when different batches of strips were used for testing, the coefficient of variation of detection results of low-concentration samples and high-concentration samples was 10.06% and 8.38% respectively, so the inter-assay CV was set as <15%. Stability test results showed that the relative deviation of test results at each time node was <15%, indicating good stability of the assay strips. The correlation coefficient between the ST-01-Eu3+@FMN based time-resolved fluorescence immunochromatography analysis and sST2 ELISA kit was 0.98. To confirm the usage of our proposed TRF-ICA for clinical samples, it was used to determine the concentration of sST2 in samples obtained from 34 patients with heart insufficiency, acute and chronic heart failure. As a result, we successfully detected a minimal concentration of 5.21 ng mL-1 and a maximum concentration of 184.26 ng mL-1 for sST2. Conclusion: this technique provides a rapid, simple and quantitative detection method for sST2 in clinics. It can help clinicians to predict the incidence of adverse events in patients with HF.

Correlation between Serum Bone Turnover Markers and Estimated Glomerular Filtration Rate in Chinese Patients with Diabetes.

OBJECTIVE: Diabetes is a growing global public health concern with many significant disease complications. Multiple studies show that bone turnover markers (BTMs) are decreased in diabetes patients, indicating impaired bone metabolism in diabetes patients. A recent study also showed that in diabetes patients, BTMs are correlated with urine albumin to creatinine ratio, an indicator of nephropathy. However, whether BTMs are correlated with estimated glomerular filtration rate (eGFR) in diabetes remains unknown. This retrospective study accessed correlations between serum BTMs and eGFR in Chinese patients with diabetes and compare levels of BTMs and eGFR between diabetic patients and healthy individuals. METHODS: This study analyzed data from 221 diabetic patients (include type1 and type 2 diabetes) and 155 healthy individuals. Serum BTM levels and eGFR were compared between diabetic patients and healthy individuals. Pearson correlation analysis was used to assess correlations between BTMs and eGFR. Multiple logistic regression analysis adjusted for gender and age was performed to measure odd ratio (OR) and 95% confidence interval (95% CI) of BTMs on diabetes. RESULTS: Patients with diabetes had significant lower 25-hydroxyvitamin D (25(OH)D) levels (15.07 ± 6.20 ng/mL) than healthy group (17.89 ± 6.41 ng/mL) (P < 0.05). For patients with diabetes, eGFR was negatively correlated with osteocalcin (OC) (r = -0.434, P < 0.05), procollagen type 1 intact N-terminal propeptide (P1NP) (r = -0.350, P < 0.05), and ß-carboxy-terminal cross-linking telopeptide of type I collagen (ß-CTX) (r = -0.179, P < 0.05) levels. For healthy people, eGFR was negatively correlated with 25(OH)D (r = -0.290, P < 0.05) levels. Multiple logistic regression analysis adjusted for age and gender (mean age of diabetes was 64.9 years and the percentage of female was 66.9%, mean age of healthy people was 48.4 years and the percentage of female was 37.4%) showed that 25(OH)D (OR = 0.909, 95%CI = 0.862 - 0.959, P < 0.05) was protective factors for diabetes. CONCLUSIONS: In the stage of diabetic nephropathy, bone turnover may accelerate. It is important to detect BTMs in the stage of diabetic nephropathy.

The Accuracy of Single MicroRNAs in Peripheral Blood to Diagnose Ovarian Cancer: An Updated Meta-Analysis.

BACKGROUND: Ovarian cancer is the 5th leading cause of death of women due to cancer in the United States. Although carbohydrate antigen 125 has a moderate diagnostic utility, the phenomenon of false-positive exists. As novel effective biomarkers, some single microRNAs (miRNAs) have diagnostic values for ovarian cancer, but the results lack consistency. In order to precisely and comprehensively assess the diagnostic value of single miRNAs for ovarian cancer, a meta-analysis is performed. METHODS: Articles concerning the diagnostic value of single miRNAs for ovarian cancer were searched from databases. The pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) with the corresponding 95% confidence interval (CI) were calculated. Area under curve (AUC) of the summary receiver-operating characteristic (SROC) curve was also calculated. RESULTS: In total, 22 studies including 8 kinds of single miRNAs were enrolled in this paper (6 studies for miR-200c, 3 studies for miR-200a and miR-200b, and 2 studies for miR-205, miR-145, miR-141, miR-429, and miR-125b). For miR-200c, the pooled SEN and SPE were, respectively, 0.768 (95% CI: 0.722-0.811) and 0.680 (95% CI: 0.624-0.732); the pooled PLR and NLR were, respectively, 2.897 (95% CI: 1.787-4.698) and 0.340 (95% CI: 0.276-0.417); the pooled DOR was 8.917 (95% CI: 4.521-17.587); and AUC of SROC curve was 0.815. For miR-200a, the pooled SEN and SPE were, respectively, 0.759 (95% CI: 0.670-0.833) and 0.717 (95% CI: 0.627-0.795); the pooled PLR and NLR were, respectively, 3.129 (95% CI: 0.997-9.816) and 0.301 (95% CI: 0.207-0.437); the pooled DOR was 11.323 (95% CI: 3.493-36.711); and AUC of SROC curve was 0.857. For miR-200b, the pooled SEN and SPE were, respectively, 0.853 (95% CI: 0.776-0.912) and 0.775 (95% CI: 0.690-0.846); the pooled PLR and NLR were, respectively, 4.327 (95% CI: 0.683-27.415) and 0.225 (95% CI: 0.081-0.625); the pooled DOR was 19.678 (95% CI: 2.812-137.72); and AUC of SROC curve was 0.90. For miR-205, miR-145, miR-141, miR-429, and miR-125b, each diagnostic value should be interpreted cautiously because only two studies were included. CONCLUSIONS: miR-200c, miR-200a, and miR-200b can be useful diagnostic biomarkers for ovarian cancer. More related studies are needed for miR-205, miR-145, miR-141, miR-429, and miR-125b.

Systematic profiling of SH3-mediated Tau-Partner interaction network in Alzheimer's disease by integrating in silico analysis and in vitro assay.

The aberrant assembly of microtubule-associated protein Tau (τ) into insoluble aggregates is closely related to Alzheimer's disease (AD), which is elicited from Tau phosphorylation events and regulated by the specific intermolecular recognition between the proline-rich PxxP motifs of Tau and the SH3 domains of its diverse partner proteins/kinases. Here, we attempt to create a systematic interaction profile for the 10 SH3 domains of previously reported Tau partners across all the 18 Tau PxxP peptides. A number of biologically functional SH3-PxxP interaction events are identified from the profile and then tested using fluorescence spectroscopy. It is revealed that (i) the region (residues 520-560) precedent to the tubulin-binding partial repeats of Tau protein is an important target of SH3 domains, where contains the three PxxP peptides τp527-536, τp530-539 and τp547-556 that exhibit different binding profiles towards the investigated SH3 domains, (ii) as compared to τp527-536 and τp547-556, the τp530-539 peptide located between them has only a modest binding potency to most SH3 domains, suggesting that the three peptides contribute unevenly to Tau-SH3 interactions, and (iii) some other Tau PxxP peptides, particularly those within the residue range 490-510 that is neighboring to the region 520-560, can also interact effectively with several SH3 domains. The SH3 domain of the well known Tau partner kinase Fyn is determined to have high or moderate affinity for an array of Tau PxxP peptides, including τp137-146, τp493-502, τp527-536 and τp547-556 (Kd ranges 15.7-85.6 µM).

Decreased miR-320 expression is associated with breast cancer progression, cell migration, and invasiveness via targeting Aquaporin 1.

Our previous studies have demonstrated that Aquaporin 1 (AQP1) is overexpressed in breast cancer. However, the mechanism remains elusive. MicroRNA 320 (miR-320) downregulation has been reported in various types of cancers, and it may regulate AQP1 expression. In this study, miR-320 and AQP1 expressions were investigated by quantitative reverse transcription-PCR, in situ hybridization, and immunohistochemistry. The clinicopathological implications of these molecules were also analyzed. We found that miR-320 expression is downregulated in both plasma and tumor tissue in human breast cancer patients. Survival analysis showed that reduced expression of miR-320 and overexpression of AQP1 are associated with worse prognosis. Luciferase assays showed that miR-320 negatively regulates AQP1 expression. In addition, cell proliferation, migration, and invasion assays were performed to investigate the effects of miR-320 on breast cancer cells. Our results showed that miR-320 overexpression inhibits cell proliferation, migration, and invasion in breast cancer cells by downregulating AQP1. These observations suggested that miR-320 downregulation may enhance AQP1 expression in breast cancer, favoring tumor progression. Our findings indicated that miR-320 and AQP1 may serve as prognostic biomarkers and therapeutic targets in the treatment of breast cancer.

HMGB1 induces lung fibroblast to myofibroblast differentiation through NF­κB­mediated TGF­ß1 release.

The proinflammatory factor high­mobility group box protein 1 (HMGB1) has been implicated in the pathogenesis of lung fibrosis; however, the role of HMGB1 in lung fibrosis remains unclear. It has previously been reported that nuclear factor (NF)­κB and transforming growth factor (TGF)­ß1 may be involved in lung fibrosis. Therefore, the present study aimed to examine the potential molecular mechanisms that underlie HMGB1­induced lung fibrosis via the regulation of NF­κB and TGF­ß1. The results demonstrated that HMGB1 stimulation increased the activation of NF­κB and the release of TGF­ß1, as well as the expression of α­smooth muscle actin (α­SMA) and collagen I in human lung fibroblasts in vitro. In addition, inhibition of NF­κB activation blocked HMGB1­induced TGF­ß1 release, as well as α­SMA and collagen I expression in lung fibroblasts. Preventing the release of TGF­ß1 inhibited HMGB1­induced α­SMA and collagen I expression; however, it had no effect on NF­κB activation. Collectively, these findings indicate that HMGB1 induces fibroblast to myofibroblast differentiation of lung fibroblasts via NF­κB­mediated TGF­ß1 release.

Comparative transcriptome analyses of deltamethrin-susceptible and -resistant Culex pipiens pallens by RNA-seq.

The widespread and improper use of pyrethroid insecticides, such as deltamethrin, has resulted in the evolution of resistance in many mosquito species, including Culex pipiens pallens. With the development of high-throughput sequencing, it is possible to massively screen pyrethroid resistance-associated gene. In this study, we used Illumina-Solexa transcriptome sequencing to identify genes that are expressed differently in deltamethrin-susceptible and -resistant strains of Culex pipiens pallens as a critical knowledge base for further studies. A total of 4,961,197,620 base pairs and 55,124,418 reads were sequenced, mapped to the Culex quinquefasciatus genome and assembled into 17,679 known genes. We recorded 1826 significantly differentially expressed genes (DEGs). Among them, 1078 genes were up-regulated and 748 genes were down-regulated in the deltamethrin-resistant strain compared to -susceptible strain. These DEGs contained cytochrome P450 s, cuticle proteins, UDP-glucuronosyltransferases, lipases, serine proteases, heat shock proteins, esterases and others. Among the 1826 DEGs, we found that the transcriptional levels of CYP6AA9 in the laboratory populations was elevated as the levels of deltamethrin resistance increased. Moreover, the expression levels of the CYP6AA9 were significantly higher in the resistant strains than the susceptible strains in three different field populations. We further confirmed the association between the CYP6AA9 gene and deltamethrin resistance in mosquitoes by RNA interfering (RNAi). Altogether, we explored massive potential pyrethroid resistance-associated genes and demonstrated that CYP6AA9 participated in the pyrethroid resistance in mosquitoes.

Venom allergen 5 is Associated With Deltamethrin Resistance in Culex pipiens pallens (Diptera: Culicidae).

The mosquito, Culex pipiens pallens (L.), is an important vector of encephalitis and filariasis in northern China. The control of these mosquitoes occurs primarily via the use of pyrethroid insecticides, such as deltamethrin. The widespread and improper application of pyrethroid has resulted in the evolution of pyrethroid resistance amongst many mosquito populations, including Cx. pipiens pallens. Previous studies using high-throughput transcriptome sequencing have identified that the venom allergen 5 gene is differentially expressed between deltamethrin-susceptible and deltamethrin-resistant Cx. pipiens pallens. In this study, quantitative real-time polymerase chain reaction analyses revealed that venom allergen 5 was significantly overexpressed in adult females of both deltamethrin-resistant laboratory populations and two field populations. The transcriptional level of venom allergen 5 in the laboratory populations was elevated as the levels of deltamethrin resistance increased. Full-length cDNAs of the venom allergen 5 gene were cloned from Cx. pipiens pallens, and contained an open reading frame of 765 bp, encoding a protein with 254 amino acids. The deduced amino acid sequence shared 100% identity with the ortholog in Culex quinquefasciatus Say. The overexpression of venom allergen 5 decreased the susceptibility of mosquito cells to deltamethrin, while knockdown of this gene by RNAi increased the susceptibility of mosquitoes to deltamethrin. This study provides the first evidence of the association between the venom allergen 5 gene and deltamethrin resistance in mosquitoes.

Identification of proteins associated with pyrethroid resistance by iTRAQ-based quantitative proteomic analysis in Culex pipiens pallens.

BACKGROUND: Mosquito control based on chemical insecticides is considered as an important element in the current global strategies for the control of mosquito-borne diseases. Unfortunately, the development of pyrethroid resistance in important vector mosquito species jeopardizes the effectiveness of insecticide-based mosquito control. To date, the mechanisms of pyrethroid resistance are still unclear. Recent advances in proteomic techniques can facilitate to identify pyrethroid resistance-associated proteins at a large-scale for improving our understanding of resistance mechanisms, and more importantly, for seeking some genetic markers used for monitoring and predicting the development of resistance. METHODS: We performed a quantitative proteomic analysis between a deltamethrin-susceptible strain and a deltamethrin-resistant strain of laboratory population of Culex pipiens pallens using isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Gene Ontology (GO) analysis was used to find the relative processes that these differentially expressed proteins were involved in. One differentially expressed protein was chosen to confirm by Western blot in the laboratory and field populations of Cx. pipiens pallens. RESULTS: We identified 30 differentially expressed proteins assigned into 10 different categories, including oxidoreductase activity, transporter activity, catalytic activity, structural constituent of cuticle and hypothetical proteins. GO analysis revealed that 25 proteins were sub-categorized into 35 hierarchically-structured GO classifications. Western blot results showed that CYP6AA9 as one of the up-regulated proteins was confirmed to be overexpressed in the deltamethrin-resistant strains compared with the deltamethrin-susceptible strains both in the laboratory and field populations. CONCLUSIONS: This is the first study to use modern proteomic tools for identifying pyrethroid resistance-related proteins in Cx. pipiens. The present study brought to light many proteins that were not previously thought to be associated with pyrethroid resistance, which further expands our understanding of pyrethroid resistance mechanisms. CYP6AA9 was overexpressed in the deltamethrin-resistant strains, indicating that CYP6AA9 may be involved in pyrethroid resistance and may be used as a potential genetic marker to monitor and predict the pyrethroid resistance level of field populations.

Identification of differentially expressed microRNAs in Culex pipiens and their potential roles in pyrethroid resistance.

Pyrethroids are the major class of insecticides used for mosquito control. Excessive and improper use of insecticides, however, has resulted in pyrethroid resistance, which has become a major obstacle for mosquito control. The development of pyrethroid resistance is a complex process involving many genes, and information on post-transcription regulation of pyrethroid resistance is lacking. In this study, we extracted RNA from mosquitoes in various life stages (fourth-instar larvae, pupae, male and female adult mosquitoes) from deltamethrin-sensitive (DS) and resistant (DR) strains. Using illumina sequencing, we obtained 13760296 and 12355472 reads for DS-strains and DR-strains, respectively. We identified 100 conserved miRNAs and 42 novel miRNAs derived from 21 miRNA precursors in Culex pipiens. After normalization, we identified 28 differentially expressed miRNAs between the two strains. Additionally, we found that cpp-miR-71 was significant down regulated in female adults from the DR-strain. Based on microinjection and CDC Bottle Bioassay data, we found that cpp-miR-71 may play a contributing role in deltamethrin resistance. The present study provides the firstly large-scale characterization of miRNAs in Cu. pipiens and provides evidence of post-transcription regulation. The differentially expressed miRNAs between the two strains are expected to contribute to the development of pyrethroid resistance.

Genome sequence of Anopheles sinensis provides insight into genetics basis of mosquito competence for malaria parasites.

BACKGROUND: Anopheles sinensis is an important mosquito vector of Plasmodium vivax, which is the most frequent and widely distributed cause of recurring malaria throughout Asia, and particularly in China, Korea, and Japan. RESULTS: We performed 454 next-generation sequencing and obtained a draft sequence of A. sinensis assembled into scaffolds spanning 220.8 million base pairs. Analysis of this genome sequence, we observed expansion and contraction of several immune-related gene families in anopheline relative to culicine mosquito species. These differences suggest that species-specific immune responses to Plasmodium invasion underpin the biological differences in susceptibility to Plasmodium infection that characterize these two mosquito subfamilies. CONCLUSIONS: The A. sinensis genome produced in this study, provides an important resource for analyzing the genetic basis of susceptibility and resistance of mosquitoes to Plasmodium parasites research which will ultimately facilitate the design of urgently needed interventions against this debilitating mosquito-borne disease.

[Presumptive role of Wolbachia in deltamethrin resistance of Culex pipiens pallens].

OBJECTIVE: To investigate the relationship between Wolbachia and deltamethrin resistance in Culex pipiens pallens. METHODS: PCR was used to detect Wolbachia in Culex pipiens pallens and qRT-PCR was performed to determine and compare the expression of Wolbachia between deltamethrin- resistant and - susceptible strains of Culex pipiens pallens. RESULTS: Wolbachia was detected in Culex pipiens pallens in the laboratory. The expression of Wolbachia was 18.42, 3.69, 4.43, 3.96, 6.31, 1.55 and 3.76 folds higher in the deltamethrin-resistant strain than in susceptible strain in the egg, 1st, 2nd, 3rd, 4th stages, and male and female adults, but there was no statistical difference in the pupae stage. The expression of Wolbachia was 2.64 folds higher in deltamethrin-resistant females than in susceptible females which were caught in Jiangxinzhou of Nanjing. CONCLUSION: Wolbachia is associated with deltamethrin resistance in Culex pipines pallens.

Ribose-phosphate pyrophosphokinase 1 (PRPS1) associated with deltamethrin resistance in Culex pipiens pallens.

Ribose-phosphate pyrophosphokinase 1 (PRPS1) was identified and isolated as a differentially expressed gene between deltamethrin-susceptible (DS) and deltamethrin-resistant (DR) Culex pipiens pallens and Aedes albopictus C6/36 cell line through microarray and 2D-Gel. An open reading frame of PRPS1 cloned from C. pipiens pallens has 1,011 bp and encodes for a 336 amino acids protein which shares high homology with Culex quinquefasciatus. Real-time polymerase chain reaction was used to determine the transcript expression level of PRPS1 in DS and DR strains. The expression levels of PRPS1 were higher in DR laboratory strains and natural population JXZ-DR, JXZ-LDR. PRPS1 was also detected and expressed at all developmental stages of C. pipiens pallens and increased expression level in DR3 strain than DS strain in the third and fourth instar larvae, female and male stages. In addition, to further investigate the role of PRPS1 in deltamethrin resistance, PRPS1 was transiently expressed in A. albopictus C6/36 cells and detected by western blotting. Cells transfected with PRPS1 had an increased resistance to deltamethrin compared with control cells. These results suggested that the increased expression level of PRPS1 may play roles in the regulation of deltamethrin resistance.

Functional characterization of an arrestin gene on insecticide resistance of Culex pipiens pallens.

BACKGROUND: Continuous and excessive application of insecticides has resulted in the rapid development of insecticide resistance in several mosquito species, including Culex pipiens pallens. Previous studies in our laboratory found that arrestin gene expression was higher in the deltamethrin-resistant (DR) strain than in the deltamethrin-susceptible (DS) strain of Cx. pipiens pallens. Similarly, other studies reported that arrestin was highly expressed in permethrin-resistant Cx. quinquefasciatus and in dichlorodiphenyltrichloroethane (DDT)-resistant Drosophila melanogaster. METHODS: Full-length cDNAs of an arrestin gene were cloned from Cx. pipiens pallens via polymerase chain reaction (PCR) and rapid amplification of cDNA end (RACE). The mRNA levels of the arrestin gene in the whole life cycle of DR and DS strains of Cx. pipiens pallens were investigated via quantitative real-time PCR. In addition, the relationship between arrestin and deltamethrin (DM) resistance were identified using genetic overexpression strategies and arrestin RNAi in mosquito cells. Cell viability was analyzed with cholecystokinin octapeptide after DM treatment. Moreover, the mRNA levels of cytochrome P450 6A1 (CYP6A1) and opsin in the transfected cells and controls were analyzed. RESULTS: Complete arrestin gene sequence was cloned and expressed throughout the life cycle of Cx. pipiens pallens. Moreover, arrestin was significantly upregulated in the DR strain, compared with that in the DS strain at the egg, pupae, and adult stages. Arrestin overexpression comparably increased the mosquito cell viability, whereas arrestin knockdown by siRNA decreased mosquito cell viability with deltamethrin (DM) treatment. Meanwhile, the mRNA levels of CYP6A1 and opsin were upregulated in mosquito cells transfected with arrestin and downregulated in mosquito cells with arrestin knockdown. CONCLUSION: This study presented the first evidence that arrestin might be associated with insecticide resistance in Cx. pipiens pallens.

Cloning and characterization of prophenoloxidase A3 (proPOA3) from Culex pipiens pallens.

The prophenoloxidase subunit A3 (proPOA3) gene was cloned from Culex pipiens pallens, which had an open reading frame of 2061 bp encoding a putative 686 amino acid protein. The deduced amino acid sequence shares 98% with proPOA3 from Culex quinquefasciatus. ProPOA3 is expressed at all developmental stages of C. pipiens pallens. Significant negative correlation was observed between proPOA3 expression and deltamethrin resistance in resistant C. pipiens pallens. Furthermore, proPOA3 expression levels were significantly lower in deltamethrin-resistant mosquitoes than in susceptible mosquitoes collected at four locations in Eastern China. However, we did not find any substantial change in proPOA3 expression in field-collected resistant Anopheles mosquitoes. Moreover, overexpressing proPOA3 in C6/36 cells led to more sensitivity to deltamethrin treatment. In laboratory and field-collected resistant C. pipiens pallens, a valine to isoleucine mutation (769G>A) and two synonymous mutations (1116G>C and 1116G>A) were identified in proPOA3. In addition, the mutation frequency of 769G>A and 1116G>C increased gradually, which corresponded with raised deltamethrin resistance levels. Taken together, our study provides the first evidence that proPOA3 may play a role in the regulation of deltamethrin-resistance in C. pipiens pallens.

Opsin3 sensitizes hepatocellular carcinoma cells to 5-fluorouracil treatment by regulating the apoptotic pathway.

Hepatocellular carcinoma (HCC) is the third most common cancer worldwide, causing over 0.5 million deaths per year, with approximately half of these in China. Chemotherapy is the optimal treatment for patients with advanced HCC, although chemoresistance has become a significant obstacle to successful anti-cancer therapy. The expression of opsin3 (OPN3), also called encephalopsin or panopsin, is lower in 5-fluorouracil (5-FU)-resistant Bel7402(5-FU) cells compared to 5-FU-sensitive Bel7402 cells. To explore the role of OPN3 in 5-FU resistance, OPN3 overexpressing (Bel7402(5-FU)-OPN3) and knockdown (Bel7402-RNAi-OPN3) cell lines were generated. Bel7402(5-FU)-OPN3 cells were more sensitive to 5-FU treatment than controls, while OPN3 knockdown resulted in a significant increase in 5-FU resistance. This result was replicated in a second HCC cell line, HepG2. Further investigation of the mechanism revealed that decreased OPN3 levels in Bel7402(5-FU) cells activated the anti-apoptotic pathway through increasing phospho-Akt and the Bcl2/Bax ratio, while overexpression of OPN3 inactivated this pathway. Taken together, these results suggest that OPN3 depletion is involved in 5-FU resistance, and that therapeutic strategies targeting OPN3 may improve HCC sensitivity to chemotherapy.