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Minimal immunogen vaccines are being developed to focus antibody responses against otherwise challenging targets, including human immunodeficiency virus (HIV), but multimerization of the minimal peptide immunogen on a carrier platform is required for activity. Star copolymers comprising multiple hydrophilic polymer chains ("arms") radiating from a central dendrimer unit ("core") were recently reported to be an effective platform for arraying minimal immunogens for inducing antibody responses in mice and primates. However, the impact of different parameters of the star copolymer (e.g., minimal immunogen density and hydrodynamic size) on antibody responses and the optimal synthetic route for controlling those parameters remains to be fully explored. We synthesized a library of star copolymers composed of poly[N-(2-hydroxypropyl)methacrylamide] hydrophilic arms extending from poly(amidoamine) dendrimer cores with the aim of identifying the optimal composition for use as minimal immunogen vaccines. Our results show that the length of the polymer arms has a crucial impact on the star copolymer hydrodynamic size and is precisely tunable over a range of 20-50 nm diameter, while the dendrimer generation affects the maximum number of arms (and therefore minimal immunogens) that can be attached to the surface of the dendrimer. In addition, high-resolution images of selected star copolymer taken by a custom-modified environmental scanning electron microscope enabled the acquisition of high-resolution images, providing new insights into the star copolymer structure. Finally, in vivo studies assessing a star copolymer vaccine comprising an HIV minimal immunogen showed the criticality of polymer arm length in promoting antibody responses and highlighting the importance of composition tunability to yield the desired biological effect.
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Dendrímeros , Animais , Dendrímeros/química , Camundongos , Polímeros/química , Portadores de Fármacos/química , Vacinas/imunologia , Vacinas/química , Vacinas/administração & dosagem , Humanos , Vacinas contra a AIDS/imunologia , Vacinas contra a AIDS/química , Vacinas contra a AIDS/administração & dosagem , PoliaminasRESUMO
Connected Automobile Vehicles (CAVs) enable cooperative driving and traffic management by sharing traffic information between them and other vehicles and infrastructures. However, malicious vehicles create Sybil vehicles by forging multiple identities and sharing false location information with CAVs, misleading their decisions and behaviors. The existing work on defending against Sybil attacks has almost exclusively focused on detecting Sybil vehicles, ignoring the traceability of malicious vehicles. As a result, they cannot fundamentally alleviate Sybil attacks. In this work, we focus on tracking the attack source of malicious vehicles by using a novel detection mechanism that relies on vehicle broadcast beacon packets. Firstly, the roadside units (RSUs) randomly instruct vehicles to perform customized key broadcasting and listening within communication range. This allows the vehicle to prove its physical presence by broadcasting. Then, RSU analyzes the beacon packets listened to by the vehicle and constructs a neighbor graph between the vehicles based on the customized particular fields in the beacon packets. Finally, the vehicle's credibility is determined by calculating the edge success probability of vehicles in the neighbor graph, ultimately achieving the detection of Sybil vehicles and tracing malicious vehicles. The experimental results demonstrate that our scheme achieves the real-time detection and tracking of Sybil vehicles, with precision and recall rates of 98.53% and 95.93%, respectively, solving the challenge of existing detection schemes failing to combat Sybil attacks from the root.
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Oxidative stress-induced lipid accumulation is mediated by lipid droplets (LDs) homeostasis, which sequester vulnerable unsaturated triglycerides into LDs to prevent further peroxidation. Here we identify the upregulation of lipopolysaccharide-binding protein (LBP) and its trafficking through LDs as a mechanism for modulating LD homeostasis in response to oxidative stress. Our results suggest that LBP induces lipid accumulation by controlling lipid-redox homeostasis through its lipid-capture activity, sorting unsaturated triglycerides into LDs. N-acetyl-L-cysteine treatment reduces LBP-mediated triglycerides accumulation by phospholipid/triglycerides competition and Peroxiredoxin 4, a redox state sensor of LBP that regulates the shuttle of LBP from LDs. Furthermore, chronic stress upregulates LBP expression, leading to insulin resistance and obesity. Our findings contribute to the understanding of the role of LBP in regulating LD homeostasis and against cellular peroxidative injury. These insights could inform the development of redox-based therapies for alleviating oxidative stress-induced metabolic dysfunction.
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Proteínas de Fase Aguda , Gotículas Lipídicas , Glicoproteínas de Membrana , Proteínas de Fase Aguda/metabolismo , Proteínas de Transporte/metabolismo , Homeostase , Gotículas Lipídicas/metabolismo , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana/metabolismo , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , TriglicerídeosRESUMO
In recent years, carbon nanotubes have emerged as a widely used nanomaterial, but their human exposure has become a significant concern. In our former study, we reported that pulmonary exposure of multiwalled carbon nanotubes (MWCNTs) promoted tumor metastasis of breast cancer; macrophages were key effectors of MWCNTs and contributed to the metastasis-promoting procedure in breast cancer, but the underlying molecular mechanisms remain to be explored. As a follow-up study, we herein demonstrated that MWCNT exposure in breast cancer cells and macrophage coculture systems promoted metastasis of breast cancer cells both in vitro and in vivo; macrophages were skewed into M2 polarization by MWCNT exposure. LncRNA NBR2 was screened out to be significantly decreased in MWCNTs-stimulated macrophages through RNA-seq; depletion of NBR2 led to the acquisition of M2 phenotypes in macrophages by activating multiple M2-related pathways. Specifically, NBR2 was found to positively regulate the downstream gene TBX1 through H3k27ac activation. TBX1 silence rescued NBR2-induced impairment of M2 polarization in IL-4 & IL-13-stimulated macrophages. Moreover, NBR2 overexpression mitigated the enhancing effects of MWCNT-exposed macrophages on breast cancer metastasis. This study uncovered the molecular mechanisms underlying breast cancer metastasis induced by MWCNT exposure.
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Neoplasias da Mama , Macrófagos , Nanotubos de Carbono , Nanotubos de Carbono/química , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Humanos , Feminino , Camundongos , Animais , Proteínas com Domínio T/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Metástase Neoplásica , Camundongos Endogâmicos BALB C , Linhagem Celular TumoralRESUMO
OBJECTIVE: Rare study of the non-coding and regulatory regions of the genome limits our ability to decode the mechanisms of fatty liver hemorrhage syndrome (FLHS) in chickens. METHODS: Herein, we constructed the high-fat diet-induced FLHS chicken model to investigate the genome-wide active enhancers and transcriptome by H3K27ac target chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-Seq) profiles of normal and FLHS liver tissues. Concurrently, an integrative analysis combining ChIP-seq with RNA-Seq and a comparative analysis with chicken FLHS, rat non-alcoholic fatty liver disease (NAFLD) and human NAFLD at the transcriptome level revealed the enhancer and super enhancer target genes and conservative genes involved in metabolic processes. RESULTS: In total, 56 and 199 peak-genes were identified in upregulated peak-genes positively regulated by H3K27ac (Cor (peak-gene correlation) ≥0.5 and log2(FoldChange) ≥1) (PP) and downregulated peak-genes positively regulated by H3K27ac (Cor (peak-gene correlation) ≥0.5 and log2(FoldChange)≤-1) (PN), respectively; then we screened key regulatory targets mainly distributing in lipid metabolism (PCK1, APOA4, APOA1, INHBE) and apoptosis (KIT, NTRK2) together with MAPK and PPAR signaling pathway in FLHS. Intriguingly, PCK1 was also significantly covered in up-regulated super-enhancers (SEs), which further implied the vital role of PCK1 during the development of FLHS. CONCLUSION: Together, our studies have identified potential therapeutic biomarkers of PCK1 and elucidated novel insights into the pathogenesis of FLHS, especially for the epigenetic perspective.
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BACKGROUND: Ropivacaine, a local anesthetic, exhibits anti-tumor effects in various cancer types. However, its specific functions and the molecular mechanisms involved in breast cancer cell stemness remain elusive. METHODS: The effects of ropivacaine on breast cancer stemness were investigated by in vitro and in vivo assays (i.e., FACs, MTT assay, mammosphere formation assay, transwell assays, western blot, and xenograft model). RNA-seq, bioinformatics analysis, Western blot, Luciferase reporter assay, and CHIP assay were used to explore the mechanistic roles of ropivacaine subsequently. RESULTS: Our study showed that ropivacaine remarkably suppressed stem cells-like properties of breast cancer cells both in vitro and in vivo. RNA-seq analysis identified GGT1 as the downstream target gene responding to ropivacaine. High GGT1 levels are positively associated with a poor prognosis in breast cancer. Ropivacaine inhibited GGT1 expression by interacting with the catalytic domain of AKT1 directly to impair its kinase activity with resultant inactivation of NF-κB. Interestingly, NF-κB can bind to the promoter region of GGT1. KEGG and GSEA analysis indicated silence of GGT1 inhibited activation of NF-κB signaling pathway. Depletion of GGT1 diminished stem phenotypes of breast cancer cells, indicating the formation of NF-κB /AKT1/GGT1/NF-κB positive feedback loop in the regulation of ropivacaine-repressed stemness in breast cancer cells. CONCLUSION: Our finding revealed that local anesthetic ropivacaine attenuated breast cancer stemness through AKT1/GGT1/NF-κB signaling pathway, suggesting the potential clinical value of ropivacaine in breast cancer treatment.
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Neoplasias da Mama , NF-kappa B , Humanos , Feminino , NF-kappa B/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ropivacaina/farmacologia , Ropivacaina/uso terapêutico , Anestésicos Locais/farmacologia , Anestésicos Locais/uso terapêutico , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Genetic variants can influence complex traits by altering gene expression through changes to regulatory elements. However, the genetic variants that affect the activity of regulatory elements in pigs are largely unknown, and the extent to which these variants influence gene expression and contribute to the understanding of complex phenotypes remains unclear. Here, we annotate 90,991 high-quality regulatory elements using acetylation of histone H3 on lysine 27 (H3K27ac) ChIP-seq of 292 pig livers. Combined with genome resequencing and RNA-seq data, we identify 28,425 H3K27ac quantitative trait loci (acQTLs) and 12,250 expression quantitative trait loci (eQTLs). Through the allelic imbalance analysis, we validate two causative acQTL variants in independent datasets. We observe substantial sharing of genetic controls between gene expression and H3K27ac, particularly within promoters. We infer that 46% of H3K27ac exhibit a concomitant rather than causative relationship with gene expression. By integrating GWAS, eQTLs, acQTLs, and transcription factor binding prediction, we further demonstrate their application, through metabolites dulcitol, phosphatidylcholine (PC) (16:0/16:0) and published phenotypes, in identifying likely causal variants and genes, and discovering sub-threshold GWAS loci. We provide insight into the relationship between regulatory elements and gene expression, and the genetic foundation for dissecting the molecular mechanism of phenotypes.
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Histonas , Sequências Reguladoras de Ácido Nucleico , Animais , Suínos/genética , Histonas/genética , Histonas/metabolismo , Fenótipo , Locos de Características Quantitativas , Fígado/metabolismoRESUMO
Nonalcoholic fatty liver disease (NAFLD) is a stress-induced liver injury related to heredity, environmental exposure and the gut microbiome metabolism. Short-chain fatty acids (SCFAs), the metabolites of gut microbiota (GM), participate in the regulation of hepatic steatosis and inflammation through the gut-liver axis, which play an important role in the alleviation of NAFLD. However, little progress has been made in systematically elucidating the mechanism of how SCFAs improve NAFLD, especially the epigenetic mechanisms and the potential therapeutic application as clinical treatment for NAFLD. Herein, we adopted PubMed and Medline to search relevant keywords such as 'SCFAs', 'NAFLD', 'gut microbiota', 'Epigenetic', 'diet', and 'prebiotic effect' to review the latest research on SCFAs in NAFLD up to November 2023. In this review, firstly, we specifically discussed the production and function of SCFAs, as well as their crosstalk coordination in the gut liver axis. Secondly, we provided an updated summary and intensive discussion of how SCFAs affect hepatic steatosis to alleviate NAFLD from the perspective of genetic and epigenetic. Thirdly, we paid attention to the pharmacological and physiological characteristics of SCFAs, and proposed a promising future direction to adopt SCFAs alone or in combination with prebiotics and related clinical drugs to prevent and treat NAFLD. Together, this review aimed to elucidate the function of SCFAs and provide new insights to the prospects of SCFAs as a therapeutic target for NAFLD.
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Solid-state polymer electrolytes (SPEs) suffer from the low ionic conductivity and poor capability of suppressing lithium (Li) dendrites, which limits their utility in the preparation of all solid-state Li-metal batteries (LMBs). It is reported here a flexible solid supramolecular electrolyte that incorporates a new anion capture agent, namely a phenylboronic acid functionalized calix[4]pyrrole (C4P), into a poly(ethylene oxide) (PEO) matrix. The resulting solid-state supramolecular electrolyte demonstrates high ionic conductivity (1.9 × 10-3 S cm-1 at 60 °C) and a high Li+ transference number ( t Li + ${t}_{{\mathrm{Li}}^{\mathrm{ + }}}$ = 0.70). Furthermore, the assembled Li|C4P-PEO-LiTFSI|LiFePO4 cell allows for stable cycling over 1200 cycles at 1 C at 60 °C, as well as good rate performance. The favorable performance of the C4P-PEO-LiTFSI SPE leads to suggest it can prove useful in the creation of high energy density solid-state LMBs.
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Non-alcoholic fatty liver disease (NAFLD) is associated with mutations in lipopolysaccharide-binding protein ( LBP), but the underlying epigenetic mechanisms remain understudied. Herein, LBP -/- rats with NAFLD were established and used to conduct integrative targeting-active enhancer histone H3 lysine 27 acetylation (H3K27ac) chromatin immunoprecipitation coupled with high-throughput and transcriptomic sequencing analysis to explore the potential epigenetic pathomechanisms of active enhancers of NAFLD exacerbation upon LBP deficiency. Notably, LBP -/- reduced the inflammatory response but markedly aggravated high-fat diet (HFD)-induced NAFLD in rats, with pronounced alterations in the histone acetylome and regulatory transcriptome. In total, 1â¯128 differential enhancer-target genes significantly enriched in cholesterol and fatty acid metabolism were identified between wild-type (WT) and LBP -/- NAFLD rats. Based on integrative analysis, CCAAT/enhancer-binding protein ß (C/EBPß) was identified as a pivotal transcription factor (TF) and contributor to dysregulated histone acetylome H3K27ac, and the lipid metabolism gene SCD was identified as a downstream effector exacerbating NAFLD. This study not only broadens our understanding of the essential role of LBP in the pathogenesis of NAFLD from an epigenetics perspective but also identifies key TF C/EBPß and functional gene SCD as potential regulators and therapeutic targets.
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Hepatopatia Gordurosa não Alcoólica , Animais , Ratos , Acetilação , Histonas/metabolismo , Lipídeos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/veterinária , Estearoil-CoA Dessaturase/metabolismoRESUMO
OBJECTIVE: We explored the relationship between TMEM16A and metastasis and development in oral squamous cell carcinoma (OSCC). STUDY DESIGN: The University of Alabama at Birmingham and Gene Expression Profiling Interactive Analysis Databases were employed to analyze the relationship between the expression of TMEM16A and the survival of patients with OSCC. TMEM16A was knocked down and overexpressed in CAL27 and SCC-4 cells, respectively, and the malignant behavior and expression of key proteins were detected. The Cdc42-NWASP pathway was inhibited, and the effects of TMEM16A and the Cdc42-NWASP pathway on promoting the malignant behavior of cancer cells were verified. A xenograft tumor model was constructed, and tumor growth, cell proliferation index, apoptosis, and Cdc42-NWASP signal pathway activity were detected. RESULTS: The expression of TMEM16A in oral cancer tissues was significantly higher than in adjacent tissues, and mice with high expression of TMEM16A had shorter survival. Overexpression of TMTM16A could significantly promote the occurrence of cancer and reduce the apoptosis of cancer cells, whereas the activity of the Cdc42 pathway was higher. Knocking down TMEM16A or inhibiting the Cdc42-NWASP pathway could reverse these results. CONCLUSION: The activation of the Cdc42-NWASP pathway by high TMEM16A expression is closely related to OSCC and may become a new therapeutic target to prevent OSCC metastasis.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Humanos , Camundongos , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Bucais/patologia , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genéticaRESUMO
Estrogen-related receptor alpha (ERRα), a member of the nuclear receptor superfamily, is strongly expressed in breast cancer cells. Its overexpression is associated with poor prognosis in triple- negative Breast Cancer (TNBC). ERRα expression could be inhibited by the downregulation of upstream oncogenic growth factors mTOR, HER2, and PI3K. Low expression of ERRα could suppress the migration and angiogenesis of tumor cells by inhibiting the activity of its downstream signals VEGF and WNT11. Studies have confirmed that ERRα inverse agonists can inhibit ERRα expression to treat breast cancer. Inverse agonists of ERRα could disrupt the interactions of ERRα with its coactivators and inhibit tumor development. Existing ERRα inverse agonists have shown moderate efficacy in inhibiting the growth of breast cancer cells. Clinical inverse agonists of ERRα have not been found in the literature. This review focuses on the research progress and the structureactivity relationship of ERRα inverse agonists, providing guidance for the research and discovery of new anti-tumor compounds for TNBC.
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Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Agonismo Inverso de Drogas , Química Farmacêutica , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/uso terapêutico , Receptor ERRalfa Relacionado ao EstrogênioRESUMO
The innate immune protection provided by cationic antimicrobial peptides (CAMPs) has been shown to extend to antiviral activity, with putative mechanisms of action including direct interaction with host cells or pathogen membranes. The lack of therapeutics available for the treatment of viruses such as Venezuelan equine encephalitis virus (VEEV) underscores the urgency of novel strategies for antiviral discovery. American alligator plasma has been shown to exhibit strong in vitro antibacterial activity, and functionalized hydrogel particles have been successfully employed for the identification of specific CAMPs from alligator plasma. Here, a novel bait strategy in which particles were encapsulated in membranes from either healthy or VEEV-infected cells was implemented to identify peptides preferentially targeting infected cells for subsequent evaluation of antiviral activity. Statistical analysis of peptide identification results was used to select five candidate peptides for testing, of which one exhibited a dose-dependent inhibition of VEEV and also significantly inhibited infectious titers. Results suggest our bioprospecting strategy provides a versatile platform that may be adapted for antiviral peptide identification from complex biological samples.
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Jacarés e Crocodilos , Vírus da Encefalite Equina Venezuelana , Encefalomielite Equina Venezuelana , Animais , Cavalos , Vírus da Encefalite Equina Venezuelana/fisiologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Encefalomielite Equina Venezuelana/tratamento farmacológico , Encefalomielite Equina Venezuelana/prevenção & controle , Bioprospecção , Replicação Viral , PeptídeosRESUMO
Dramatic phenotypic differences between domestic pigs and wild boars (Sus scrofa) provide opportunities to investigate molecular mechanisms underlying the formation of complex traits, including morphology, physiology and behaviour. Most studies comparing domestic pigs and wild boars have focused on variations in DNA sequences and mRNA expression, but not on epigenetic changes. Here, we present a genome-wide comparative study on H3K27ac enhancer activities and the corresponding mRNA profiling in the brain and liver tissues of adult Bama Xiang pigs (BMXs) and Chinese wild boars (CWBs). We identified a total of 1,29,487 potential regulatory elements, among which 11,241 H3K27ac peaks showed differential activity between CWBs and BMXs in at least one tissue. These peaks were overrepresented by binding motifs of FOXA1, JunB, ATF3 and BATF, and overlapped with differentially expressed genes that are involved in female mating behaviour, response to growth factors and hormones, and lipid metabolism. We also identified 4118 nonredundant super-enhancers from ChIP-Seq data on H3K27ac. Notably, we identified differentially active peaks located close to or within candidate genes, including TBX19, MSTN, AHR and P2RY1, which were identified in DNA sequence-based population differentiation studies. This study generates a valuable dataset on H3K27ac profiles of the brain and liver from domestic pigs and wild boars, which helps gain insights into the changes in enhancer activities from wild boars to domestic pigs.
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BACKGROUND: Periodontitis is a common oral immune inflammatory disease and early detection plays an important role in its prevention and progression. However, there are no accurate biomarkers for early diagnosis. OBJECTIVE: This study screened periodontitis-related diagnostic biomarkers based on weighted gene correlation network analysis and machine algorithms. METHODS: Transcriptome data and sample information of periodontitis and normal samples were obtained from the Gene Expression Omnibus (GEO) database, and key genes of disease-related modules were obtained by bioinformatics. The key genes were subjected to Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and 5 machine algorithms: Logistic Regression (LR), Random Forest (RF), Gradient Boosting Decisio Tree (GBDT), Extreme Gradient Boosting (XGBoost), and Support Vector Machine (SVM). Expression and correlation analysis were performed after screening the optimal model and diagnostic biomarkers. RESULTS: A total of 47 candidate genes were obtained, and the LR model had the best diagnostic efficiency. The COL15A1, ICAM2, SLC15A2, and PIP5K1B were diagnostic biomarkers for periodontitis, and all of which were upregulated in periodontitis samples. In addition, the high expression of periodontitis biomarkers promotes positive function with immune cells. CONCLUSION: COL15A1, ICAM2, SLC15A2 and PIP5K1B are potential diagnostic biomarkers of periodontitis.
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Perfilação da Expressão Gênica , Periodontite , Algoritmos , Biomarcadores , Biologia Computacional , Ontologia Genética , Humanos , Periodontite/diagnóstico , Periodontite/genéticaRESUMO
The limited knowledge of genomic noncoding and regulatory regions has restricted our ability to decipher the genetic mechanisms underlying complex traits in pigs. In this study, we characterized the spatiotemporal landscape of putative enhancers and promoters and their target genes by combining H3K27ac-targeted ChIP-Seq and RNA-Seq in fetal (prenatal days 74-75) and adult (postnatal days 132-150) tissues (brain, liver, heart, muscle and small intestine) sampled from Asian aboriginal Bama Xiang and European highly selected Large White pigs of both sexes. We identified 101,290 H3K27ac peaks, marking 18,521 promoters and 82,769 enhancers, including peaks that were active across all tissues and developmental stages (which could indicate safe harbor locus for exogenous gene insertion) and tissue- and developmental stage-specific peaks (which regulate gene pathways matching tissue- and developmental stage-specific physiological functions). We found that H3K27ac and DNA methylation in the promoter region of the XIST gene may be involved in X chromosome inactivation and demonstrated the utility of the present resource for revealing the regulatory patterns of known causal genes and prioritizing candidate causal variants for complex traits in pigs. In addition, we identified an average of 1,124 super-enhancers per sample and found that they were more likely to show tissue-specific activity than ordinary peaks. We have developed a web browser to improve the accessibility of the results ( http://segtp.jxau.edu.cn/pencode/?genome=susScr11 ).
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Sequenciamento de Cromatina por Imunoprecipitação , Genoma , Animais , Feminino , Expressão Gênica , Gravidez , Regiões Promotoras Genéticas/genética , Suínos/genéticaRESUMO
Aim: To evaluate the regulatory landscape underlying the active enhancer marked by H3K27ac in high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) in rats. Materials & methods: H3K27ac chromatin immunoprecipitation and high-throughput RNA sequencing to construct regulatory profiles and transcriptome of liver from NAFLD rat model induced by HFD. De novo motif analysis for differential H3K27ac peaks. Functional enrichment, Kyoto Encyclopedia of Genes and Genomes pathway and protein-protein interaction network were examined for differential peak-genes. The mechanism was further verified by western blot, chromatin immunoprecipitation-quantitative PCR and real-time PCR. Results: A total of 1831 differential H3K27ac peaks were identified significantly correlating with transcription factors and target genes (CYP8B1, PLA2G12B, SLC27A5, CYP7A1 and APOC3) involved in lipid and energy homeostasis. Conclusion: Altered acetylation induced by HFD leads to the dysregulation of gene expression, further elucidating the epigenetic mechanism in the etiology of NAFLD.
What is this summary about? Nonalcoholic fatty liver disease (NAFLD) is a typical metabolic disease, which is becoming the most common liver disease in the world. Despite its high prevalence and morbidity, there is currently no effective diagnostic or approved therapy, and the molecular mechanisms for NAFLD have not been fully clarified, especially for epigenetics. Herein, we focused on histone modification and investigated the impact of active enhancer to explore the epigenetic regulation of NAFLD, seeking new targets for the prevention and treatment of the disease. What were the results? We identified the alteration of H3K27 acetylation and differential gene expression, enriched potential transcription-factor binding motifs and highlighted the hub risk genes of CYP8B1, PLA2G12B, SLC27A5, CYP7A1 and APOC3 in a NAFLD rat model. What do the results mean? This work emphasized the vital roles of histone modification of H3K27ac in a high-fat-diet-induced NAFLD model, which could regulate the expression of key genes and transcription factor binding motifs, and H3K27ac induced the formation of NAFLD. Targeting the H3K27ac modification, dysregulated target genes and enriched pathways may be of great importance for NAFLD prediction and prevention, and serve as a valuable resource for genome-wide studies of epigenomic regulation in lipid metabolic disease.
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Hepatopatia Gordurosa não Alcoólica , Animais , Ratos , Acetilação , Dieta Hiperlipídica , Epigênese Genética , Hepatopatia Gordurosa não Alcoólica/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The epigenetic regulation of gene expression is implicated in complex diseases in humans and various phenotypes in other species. There has been little exploration of regulatory elements in the pig. Here, we performed chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-Seq) to profile histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 27 acetylation (H3K27ac) in the pituitary gland of adult Bama Xiang and Large White pigs, which have divergent evolutionary histories and large phenotypic differences. We identified a total of 65,044 non-redundant regulatory regions, including 23,680 H3K4me3 peaks and 61,791 H3K27ac peaks (12,318 proximal and 49,473 distal), augmenting the catalog of pituitary regulatory elements in pigs. We found 793 H3K4me3 and 3,602 H3K27ac peaks that show differential activity between the two breeds, overlapping with genes involved in the Notch signaling pathway, response to growth hormone (GH), thyroid hormone signaling pathway, and immune system, and enriched for binding motifs of transcription factors (TFs), including JunB, ATF3, FRA1, and BATF. We further identified 2,025 non-redundant super enhancers from H3K27ac ChIP-seq data, among which 302 were shared in all samples of cover genes enriched for biological processes related to pituitary function. This study generated a valuable dataset of H3K4me3 and H3K27ac regions in porcine pituitary glands and revealed H3K4me3 and H3K27ac peaks with differential activity between Bama Xiang and Large White pigs.
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OBJECTIVE: Cryoablation can directly kill tumor cells through sudden changes in temperature. It can also enhance lymphocyte function and cause distant tumor regression far from the ablation treatment area. In order to further explore the changes of immune function after cryoablation, the changes of Kupffer cells (KCs), the main immune cells in the liver, and their effects on untreated tumors in vivo were studied. METHODS: Rabbit VX2 liver cancer models were constructed. The growth of liver tumors was confirmed by ultrasound after transplantation for 3 weeks. Fifteen Japanese white rabbits were divided into a tumor control group and cryoablation group. Cryoablation group was treated with cryoablation of a single or partial tumor. Histologic and immunohistochemical changes of the treatment area and untreated tumor area before and after cryoablation were observed, and the phagocytic function changes of KCs around the untreated area and treatment area were observed by electron microscopy. RESULTS: Cryoablation areas showed necrosis, infiltration of inflammatory cells (including KCs), and fibrosis of tissue. The number of inflammatory cells in the unfrozen tumor area was increased in the same treated rabbit. There was a significant difference in the maximum diameter of unfrozen tumors between the frozen group and control group at 15th days after cryoablation (P<0.05), while the difference was not obvious at the 3rd and 7th day (P>0.05). Electron microscopy showed that the number of debris fragments engulfed by KCs around the tumor after cryoablation was significantly higher than that of the control group. In the same rabbit, we compared the amount of debris between tissue surrounding the unfrozen area and around the cryoablation area. There was a significant difference on the 3rd day after cryoablation, P=0.043, while there was no significant difference on the 7th day, P=0.348. CONCLUSION: After cryoablation, inflammatory cells aggregated around the cryoablated area. The activity of KCs had been increased and the function of phagocytosis enhanced. KCs had a certain inhibitory effect on the untreated tumor in the same animal at the early stage (within 15 days), but it was not enough to restrain the growth of the untreated tumors.
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Sepsis is an organ dysfunction caused by the dysregulated inflammatory response to infection. Lipopolysaccharide-binding protein (LBP) binds to lipopolysaccharide (LPS) and modulates the inflammatory response. A rare systematic study has been reported to detect the effect of LBP gene during LPS-induced sepsis. Herein, we explored the RNA sequencing technology to profile the transcriptomic changes in liver tissue between LBP-deficient rats and WT rats at multiple time points after LPS administration. We proceeded RNA sequencing of liver tissue to search differentially expressed genes (DEGs) and enriched biological processes and pathways between WT and LBP-deficient groups at 0 h, 6 h, and 24 h. In total, 168, 284, and 307 DEGs were identified at 0 h, 6 h, and 24 h, respectively, including Lrp5, Cyp7a1, Nfkbiz, Sigmar1, Fabp7, and Hao1, which are related to the inflammatory or lipid-related process. Functional enrichment analysis revealed that inflammatory response to LPS mediated by Ifng, Cxcl10, Serpine1, and Lbp was enhanced at 6 h, while lipid-related metabolism associated with C5, Cyp4a1, and Eci1 was enriched at 24 h after LPS administration in the WT samples. The inflammatory process was not found when the LBP gene was knocked out; lipid-related metabolic process and peroxisome proliferator-activated receptor (PPAR) signaling pathway mediated by Dhrs7b and Tysnd1 were significantly activated in LBP-deficient samples. Our study suggested that the invading LPS may interplay with LBP to activate the nuclear factor kappa B (NF-κB) signaling pathway and trigger uncontrolled inflammatory response. However, when inhibiting the activity of NF-κB, lipid-related metabolism would make bacteria removal via the effect on the PPAR signaling pathway in the absence of LBP gene. We also compared the serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels using the biochemistry analyzer and analyzed the expression of high mobility group box 1 (HMGB1) and cleaved-caspase 3 with immunohistochemistry, which further validated our conclusion.