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Type I interferons (IFNs), key antiviral cytokines, evolve to adapt with ever-changing viral threats during vertebrate speciation. Due to novel pathogenic pressure associated with Suidae speciation and domestication, porcine IFNs evolutionarily engender both molecular and functional diversification, which have not been well addressed in pigs, an important livestock species and animal model for biomedical sciences. Annotation of current swine genome assembly Sscrofa10.2 reveals 57 functional genes and 16 pseudogenes of type I IFNs. Subfamilies of multiple IFNA, IFNW and porcine-specific IFND genes are separated into four clusters with ∼60 kb intervals within the IFNB/IFNE bordered region in SSC1, and each cluster contains mingled subtypes of IFNA, IFNW and IFND. Further curation of the 57 functional IFN genes indicates that they include 18 potential artifactual duplicates. We performed phylogenetic construction as well as analyses of gene duplication/conversion and natural selection and showed that porcine type I IFN genes have been undergoing active diversification through both gene duplication and conversion. Extensive analyses of the non-coding sequences proximal to all IFN coding regions identified several genomic repetitive elements significantly associated with different IFN subtypes. Family-wide studies further revealed their molecular diversity with respect to differential expression and restrictive activity on the resurgence of a porcine endogenous retrovirus. Based on predicted 3-D structures of representative animal IFNs and inferred activity, we categorized the general functional propensity underlying the structure-activity relationship. Evidence indicates gene expansion of porcine type I IFNs. Genomic repetitive elements that associated with IFN subtypes may serve as molecular signatures of respective IFN subtypes and genomic mechanisms to mediate IFN gene evolution and expression. In summary, the porcine type I IFN profile has been phylogenetically defined family-wide and linked to diverse expression and antiviral activity, which is important information for further biological studies across the porcine type I IFN family.  相似文献   

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目的:利用大肠杆菌系统表达重组人Ⅲ型干扰素λ1(rhIFN-λ1),并进行纯化,以比较其与重组人干扰素-α2b(rhIFN-α2b)生物学活性的差异。方法:密码子优化的rhIFN-λ1基因与pET-44a载体连接构建原核表达质粒,在大肠杆菌BL21(DE3)中表达,表达产物经系列层析纯化;采用细胞病变抑制法比较纯化的rhIFN-λ1与rhIFN-α2b、市售rhIFN-λ1的抗病毒活性;采用MTS法比较这些干扰素的抗肿瘤细胞增殖活性。结果:基因优化后的rhIFN-λ1在大肠杆菌中得以高效表达,用所建立的纯化工艺可制备得到纯度达95.7%的rhIFN-λ1;rhIFN-λ1的抗病毒比活性为3.2×105 U/mg,比市售rhIFN-λ1的比活性(1.1×105 U/mg)略高,抗肿瘤细胞增殖活性为rhIFN-α2b的1.7倍。结论:获得的rhIFN-λ1具有剂量依赖的抗病毒活性和抗增殖活性,其抗病毒活性比市售rhIFN-λ1略高,抗细胞增殖活性高于rhIFN-α2b,提示rhIFN-λ1有较大的应用前景。  相似文献   

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Colon cancer is one of the most common human malignancies, and chemotherapy cannot yet prevent recurrence in all patients. Essential oils are phytocomplexes with antiproliferative properties. In this study, we elucidated the antiproliferative properties and the effect on cell cycle progression of Sicilian Salvia officinalis essential oil and its three main compounds, α‐thujone, 1,8‐cineole (eucalyptol) and camphor, on three human colon cancer cell lines. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography. Cell proliferation was evaluated by MTT assay, and the cell cycle distribution was determined by flow cytometry. Thirty‐four compounds were identified in the tested essential oil. Growth inhibition was observed after 72 h, with an impact on cell cycle progression and no effect on the viability of normal colonic epithelial cells. The study shows that S. officinalis essential oil and its three main components have an in vitro antiproliferative effect on colon cancer cells.  相似文献   

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干扰素的信号传导和抗病毒效应机制   总被引:1,自引:0,他引:1  
干扰素是一种具有抗病毒、抗增殖和免疫调节功能的细胞因子,它在宿主天然免疫防御中起着重要的作用。干扰素诱导的信号通路除了最初的Jak-Stat途径以外,很多新发现的信号途径对于干扰素反应也是必需的。干扰素反应最终导致抗病毒的效应蛋白通路,包括2′,5′-寡聚腺苷酸合成酶、蛋白激酶、ISG15等途径。这些效应蛋白通过抑制病毒转录、降解病毒RNA、抑制翻译和修饰蛋白的功能来控制病毒复制的过程。  相似文献   

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Grapes are rich in phytochemicals with many proven health benefits. Phenolic profiles, antioxidant and antiproliferative activities of twenty-four selected Vitis vinifera grape cultivars were investigated in this study. Large ranges of variation were found in these cultivars for the contents of total phenolics (95.3 to 686.5 mg/100 g) and flavonoids (94.7 to 1055 mg/100 g) and antioxidant activities (oxygen radical absorbance capacity 378.7 to 3386.0 mg of Trolox equivalents/100 g and peroxylradical scavenging capacity14.2 to 557 mg of vitamin C equivalents/100 g), cellular antioxidant activities (3.9 to 139.9 µmol of quercetin equivalents/100 g without PBS wash and 1.4 to 95.8 µmol of quercetin equivalents /100 g with PBS wash) and antiproliferative activities (25 to 82% at the concentrations of 100 mg/mL extracts).The total antioxidant activities were significantly correlated with the total phenolics and flavonoids. However, no significant correlations were found between antiproliferative activities and total phenolics or total flavonoids content. Wine grapes and color grapes showed much higher levels of phytochemicals and antioxidant activities than table grapes and green/yellow grapes. Several germplasm accessions with much high contents of phenolics and flavonoids, and total antioxidant activity were identified. These germplasm can be valuable sources of genes for breeding grape cultivars with better nutritional qualities of wine and table grapes in the future.  相似文献   

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Novel enamine derivatives were synthesized from the reaction of lactone and chalcones and their antiproliferative and cytotoxic activities against six cancer cell lines (e. g., HeLa, HT29, A549, MCF7, PC3 and Hep3B) and one normal cell lines (e. g., FL) were investigated along with their mode of interactions with CT‐DNA. Most of the enamine derivatives with IC50 values of 86–168 μM demonstrated much stronger antiproliferative activity than the starting molecules against the cancer cells. While, among the enamine derivatives, four compounds displayed higher cytotoxic potency than the control drugs (5‐fluorouracil and cisplatin) against the Hep3B cell lines, these compounds did not exhibit any significant toxicity against normal cells, FL. The UV/VIS spectral data suggest that eight compounds cause hypochromism with a slight bathochromic shift (~6 nm), indicating that they bind to the DNA by way of an intercalative or minor groove binding mode. The binding constants of the compounds are in the range of 0.1×103 M?1–2.3×104 M?1. The antiproliferative activity of studied enamine derivatives could possibly be due to their DNA binding as well as their cytotoxic properties. In addition to these assays, the chalcones and enamine derivatives were investigated by molecular docking to calculate the synergistic effect of antiproliferative activities against six human cancer cell lines.  相似文献   

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Post-translational protein modification is an important strategy for the regulation of the cell proteome independent of the need for new gene expression. Ubiquitin and ubiquitin-like modifiers mediate the regulation of protein levels, signaling pathways, vesicular trafficking, and many other cellular processes through their covalent conjugation to proteins. Interferon stimulated gene 15 (ISG15) is a ubiquitin-like modifier induced by type I interferon. In addition to conjugating to potentially hundreds of target proteins, ISG15 can be found in an unconjugated form both inside of the cell and released from interferon stimulated cells into the extracellular environment. Due to its robust expression after type I interferon stimulation and the broad panel of proteins that it targets, ISG15 has drawn much attention as a potential regulator of the immune response and has been shown to mediate protection in a number of different viral infection models. Here we will review the current state of the field of ISG15, the viruses against which ISG15 mediates protection, and the mechanisms by which ISG15 exerts antiviral activity.  相似文献   

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The development of resistance in response to interferon depends on cellular RNA synthesis and probably also on cellular protein synthesis. The evidence for these requirements is reviewed, as well as the proposal that this evidence indicates the existence of a specific response of the cell to interferon, involving the induced synthesis of an antiviral protein. Direct evidence for such an interpretation has not been obtained, and alternative explanations are discussed which do not require quantitative or qualitative differences in the RNA and protein made in cells exposed to interferon. The possible role of the ribosome in the antiviral action of interferon is also discussed.  相似文献   

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Russian Journal of Bioorganic Chemistry - Nowadays the determination of inhibitors of carbonic anhydrase isoenzymes (CAs) have become one of the main goals of drug design studies, and inhibitors of...  相似文献   

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Potentiation of the Antiviral Activity of Interferon by Actinomycin D   总被引:6,自引:0,他引:6  
INTERFERON induces cellular synthesis of the antiviral protein which is probably responsible for conferring antiviral activities. Although this antiviral protein has not been isolated, indirect evidence favours a two-step mechanism in the development of cellular resistance to viruses. Taylor1 and subsequently Friedman and Sonnabend2 and Lockart3 have shown that from 0 to 4 h after the treatment of the cells with interferon, the induction of the antiviral state requires the integrity of the cellular apparatus for protein synthesis. Cassingena et al.4 have shown that in somatic mouse-monkey hybrid cells, the genes which code for the production and action of interferon are located at different chromosomal sites.  相似文献   

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Defensins are an effector component of the innate immune system with broad antimicrobial activity. Humans express two types of defensins, α- and β-defensins, which have antiviral activity against both enveloped and non-enveloped viruses. The diversity of defensin-sensitive viral species reflects a multitude of antiviral mechanisms. These include direct defensin targeting of viral envelopes, glycoproteins, and capsids in addition to inhibition of viral fusion and post-entry neutralization. Binding and modulation of host cell surface receptors and disruption of intracellular signaling by defensins can also inhibit viral replication. In addition, defensins can function as chemokines to augment and alter adaptive immune responses, revealing an indirect antiviral mechanism. Nonetheless, many questions regarding the antiviral activities of defensins remain. Although significant mechanistic data are known for α-defensins, molecular details for β-defensin inhibition are mostly lacking. Importantly, the role of defensin antiviral activity in vivo has not been addressed due to the lack of a complete defensin knockout model. Overall, the antiviral activity of defensins is well established as are the variety of mechanisms by which defensins achieve this inhibition; however, additional research is needed to fully understand the role of defensins in viral pathogenesis.  相似文献   

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Abstract

cis-3-Aminomethylcyclopentylmethanol (4), prepared from norbornene (5) in four steps and 51 % overall yield, was used as a precursor in the synthesis of carbocylic nucleosides 13–18 containing guanine and 8-azaguanine bases. None of these compounds had appreciable activity against fourteen viruses in the concentration range tested. Compounds 13 and 16 showed cytotoxicity to all or part of the cell lines used.  相似文献   

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越来越多的聚乙二醇修饰蛋白研发上市。为适应这类制品的发展,与之相关的中国药品通用名命名原则也需要不断更新。介绍了PEG修饰蛋白技术的发展以及WHO国际非专利药品名(INN)命名委员会对这类制品的命名情况,讨论了我国对这类制品的命名原则和方法。  相似文献   

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我们应用中和试验在不同细胞上对干扰素血清与猪脾细胞干扰素(PSIFN)及人干扰素(HuIFN-α)的中和能力进行了试验,结果证明HuIFN-α多克隆抗体具有明显的中和PSIFN的能力。而人免疫干扰素(Hu IFN-γ)抗体具有微弱的中和猪脾细胞干扰素能力。猪脾细胞干扰素不仅可在同源细胞表现出抗病毒活性,而且可在异源细胞表现出较高的抗病毒活性。应用人白细胞干扰素多克隆抗体亲和层析可有效地分离猪脾细胞干扰素,证实猪脾细胞干扰素与人白细胞干扰素之间具有高度的同源性关系。  相似文献   

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干扰素调节因子-3(interferon regulatory factor-3,IRF-3)是IRF家族中重要 转录因子之一,在调控干扰素(interferon, IFN)基因表达和抗病毒天然免疫反应中具有重要作 用. 最新发现的MITA (mediator of IRF-3 activation, 又称STING/ERIS)蛋白是宿主抗病 毒天然免疫反应中的一种重要调节分子. 病毒侵染时,MITA与IRF-3相互作用,特异性激活 IRF-3,并募集TANK结合激酶1(TANK binding kinase 1, TBK1)与IFN通路中的线粒体抗 病毒信号蛋白MAVS(mitochondrial anti-viral signaling protein)形成复合物,且MITA可 被TBK1磷酸化,诱导Ⅰ型IFN及IFN刺激基因(interferon stimulate genes, ISG)的表达 ,诱发抗病毒天然免疫反应. 同时还发现,泛素连接酶RNF5(ring finger protein 5)可对MITA 发生泛素化修饰从而抑制其对IRF-3活化,实现对宿主抗病毒天然免疫反应负调节作用. 本 室研究发现,严重性急性呼吸系统综合症冠状病毒(severe acute respiratory syndrome co ronavirus, SARS-CoV)和人类新型冠状病毒(human coronavirus NL63, HCoV-NL63)的 木瓜样蛋白酶(papain-like protease, PLP)利用其特有的去泛素化酶(deubiquitinase, DUB)活性,通过宿主细胞泛素-蛋白酶体信号系统对IRF-3的泛素化等翻译后修饰进行调节 ,从而成为该种病毒逃逸机体抗病毒防御系统主要手段之一.  相似文献   

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