共查询到18条相似文献，搜索用时 187 毫秒
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近年来的研究表明,内源性逆转录病毒作为哺乳动物基因组的重要组成部分,在与宿主共进化过程中发挥重要作用.对内源性绵羊肺腺瘤病毒的研究,为揭示哺乳动物内源性逆转录病毒与宿主共进化关系提供了一个独特的模型系统.内源性绵羊肺腺瘤病毒在与宿主共进化过程中不断的增强自身的宿主适应性,通过取代宿主原有的促进孕体发育及胎盘形成的机制而... 相似文献
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慢病毒载体的研究进展及应用 总被引：1，自引：1，他引：0
慢病毒载体是近年来受到广泛关注的一种逆转录病毒载体,具有更安全、转移效率高、可将目的基因整合入宿主基因组和可感染非分裂期细胞等优点,因此有望成为理想的基因转移载体,并在临床和生产实践中广泛应用。作者主要以HIV-1为代表对慢病毒载体的构建及其在基因治疗和转基因动物生产中的应用作一综述。 相似文献
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线粒体在调控卵母细胞成熟和发育中的作用 总被引：1，自引：0，他引：1
《中国畜牧杂志》2016,(7)
线粒体是真核生物细胞重要的细胞器,其不仅通过氧化代谢为细胞发育提供能量,而且与生长、发育、衰老和凋亡等重要生物过程密切相关。许多研究表明,动物卵母细胞成熟期间积累了丰富的线粒体,其分布、mt DNA拷贝数和代谢活性均能影响卵母细胞的发育潜能,并能支持胚胎发育通过基因组激活阶段。线粒体功能异常将导致卵母细胞老化,降低其受精后的胚胎发育能力,进而影响动物的繁殖力。本文就卵母细胞线粒体的产生和分布、mt DNA及其对卵母细胞成熟、发育调控作用等方面进行了综述。 相似文献
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哺乳动物个体由终端分化的单倍体精子和卵子受精融合成的双倍体受精卵发育而来。在胚胎发育的初始阶段,合子基因组处于休眠状态,胚胎发育调控由卵母细胞内母源调控逐渐转换为合子基因组调控(Maternal-Zygotic Transition,MZT)。在此期间,随着母源物质的清除,合子基因组激活(Zygotic Genome Activation,ZGA),但调控MZT的具体分子机制还不清楚。最新研究表明,DNA甲基化、染色质重塑、组蛋白表观修饰、ncRNA在MZT和ZGA中发挥重要的作用。本文总结了上述4种表观修饰在动物植入前胚胎MZT中的生物学功能和特异的分子机制,对揭示动物胚胎MZT的调控机理有借鉴意义。 相似文献
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DNA甲基化(DNA methylation)是一种动态、可逆并可以遗传的表观遗传修饰模式,主要发生在哺乳动物原始生殖细胞和早期胚胎发育过程中,能够通过高动态和协同的核酶网络附着在DNA的CpG区域,同时还通过改变调控区域的功能状态进而调控基因表达且不影响DNA序列所携带的遗传信息。DNA甲基化主要涉及基因组印迹、转座元件沉默、X染色体失活和衰老等多种关键生理过程,在哺乳动物卵母细胞和胚胎发育中发挥着重要作用。本文介绍了DNA甲基化的建立与去除机制及其生物学功能,重点阐述了DNA甲基化在哺乳动物卵母细胞和胚胎发育过程中精准生成、维持、读取和删除等动态变化过程,为进一步研究哺乳动物表观遗传调控提供参考依据。 相似文献
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《蚕业科学》2015,(1)
研究病毒内源性非编码小RNA(VmiRNA)的靶标基因,有助于阐释病毒和宿主的互作关系及制定对病毒的防控策略。利用Solexa高通量测序技术及生物信息学方法,从柞蚕核型多角体病毒(Ap NPV)基因组中筛选出VmiRNA成熟体MD5,在预测其作用的宿主靶基因基础上,通过GO数据库分析靶基因的功能。结果显示由Ap NPV的VmiRNA MD5调控的宿主靶基因涉及细胞组成、分子功能、生物学过程等生物学途径,主要参与细胞内的分子结合、酶催化和免疫反应,其中与柞蚕免疫相关的靶基因共有4个。实时荧光定量PCR检测柞蚕蛹经Ap NPV诱导处理后VmiRNA MD5在脂肪体内明显上调表达(与对照相比提高了8倍),而与宿主免疫相关的3个靶基因的表达水平明显下调。对VmiRNA MD5 5'端上游启动子序列结构的分析显示,其含有免疫相关转录因子GMCSF、p53等的结合位点。推测VmiRNA MD5可能参与调控宿主柞蚕免疫相关基因的表达。 相似文献
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Geminin是一种25kD的核蛋白,在细胞增殖、细胞分化、胚胎发育以及肿瘤发生等多方面均发挥着重要作用。在不同发育阶段,Geminin在不同的区域表达,可作为抑制因子或是诱导因子参与胚胎发育的调节。而通过建立相关geminin的转基因斑马鱼来调控其在体内的表达上调或下调,是研究geminin功能的一种常用方法。主要对geminin相关的结构、功能及其在胚胎发育方面作用的研究进展以及相关的实验技术进行了综述。 相似文献
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Endogenous retroviruses (ERVs) are present in the genome of all vertebrates and are remnants of ancient exogenous retroviral infections of the host germline transmitted vertically from generation to generation. Sheep betaretroviruses offer a unique model system to study the complex interaction between retroviruses and their host. The sheep genome contains 27 endogenous betaretroviruses (enJSRVs) related to the exogenous and pathogenic Jaagsiekte sheep retrovirus (JSRV), the causative agent of a transmissible lung cancer in sheep. The enJSRVs can protect their host against JSRV infection by blocking early and late steps of the JSRV replication cycle. In the female reproductive tract, enJSRVs are specifically expressed in the uterine luminal and glandular epithelia as well as in the conceptus (embryo and associated extraembryonic membranes) trophectoderm and in utero loss-of-function experiments found the enJSRVs envelope (env) to be essential for conceptus elongation and trophectoderm growth and development. Collectively, available evidence in sheep and other mammals indicate that ERVs coevolved with their hosts for millions of years and were positively selected for biological roles in genome plasticity and evolution, protection of the host against infection of related pathogenic and exogenous retroviruses, and placental development. 相似文献
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绵羊基因组中内源性绵羊肺腺瘤病毒相关序列的确定 总被引：1，自引：0，他引：1
绵羊都含有与绵羊肺腺瘤病毒(Jaagsiekte sheep retrovirus,JSRV)密切相关的15~20拷贝内源性绵羊肺腺瘤病毒(enJSRV)相关序列。宿主可利用内源性病毒来预防致病性反转录病毒的感染,一些内源性病毒可以有效地干扰相关外源性病毒的复制。本试验通过分子生物学手段确定了蒙古绵羊基因组中含有enJSRV6和enJSRV10两个内源性病毒基因而内蒙古白绒山羊中未发现。通过比较内、外源病毒LTR序列的酶切图谱,获得专一作用外源性病毒的核酸内切酶M spⅠ、TfiⅠ、BsaWⅠ,如果将酶切与聚合酶链式反应(PCR)相结合,不需要经过测序就可分辨enJS-RV和外源性绵羊肺腺瘤病毒(exJSRV),形成"酶切-PCR"检测技术,将为绵羊肺腺瘤病的快速诊断提供了新的手段。 相似文献
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非洲猪瘟(African swine fever，ASF)是由非洲猪瘟病毒(African swine fever virus，ASFV)感染猪引起的一种急性、烈性、高度接触性传染病，至今没有研发出安全有效的疫苗，一旦暴发会造成重大经济损失。ASFV在和宿主长期作用过程中，通过抑制干扰素和炎症反应，调节凋亡、自噬及细胞免疫等多种途径逃逸机体免疫反应促进自身复制，但具体的机制仍不完全清楚。ASFV复杂的免疫逃逸机制可能是阻碍有效疫苗研发的关键因素之一。借助生物信息学技术对ASFV的基因组和蛋白质组深入分析，筛选病毒的免疫调控关键基因和保护性抗原表位，将在ASFV免疫逃逸分子机制的研究与疫苗研发中发挥重要作用。本文主要对ASFV感染引起的免疫应答反应及可能的免疫逃逸机制研究进行概述，以期为ASF疫苗研制及综合防控提供思路。 相似文献
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寄生虫在入侵机体时必须具备逃避机体免疫,破坏宿主免疫屏障才能感染,这种入侵过程必然和宿主机体的免疫系统发生联系,不但使宿主的先天免疫细胞功能缺失,而且获得性免疫也受到抑制。寄生虫感染均不同程度地伴随免疫损伤,宿主在感染寄生虫后产生的免疫应答中,细胞因子作为免疫过程中的介质起到关键作用,主要是调节机体细胞免疫抗虫,保护机体不被感染,其中巨噬细胞是主要功能的承担者。本文将阐述细胞因子在寄生虫感染过程中所发挥的免疫作用,为解决寄生虫感染的防控问题奠定基础,同时为寄生虫的研究提供新的思路。 相似文献
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The intestinal immune system is affected by various factors during its development, such as maternal antibodies, host genes, intestinal microbial composition and activity, and various stresses (such as weaning stress). Intestinal microbes may have an important impact on the development of the host immune system. Appropriate interventions such as probiotics may have a positive effect on intestinal immunity by regulating the composition and activity of intestinal microbes. Moreover, probiotics participate in the regulation of host health in many ways; for instance, by improving digestion and the absorption of nutrients, immune response, increasing the content of intestinal-beneficial microorganisms, and inhibiting intestinal-pathogenic bacteria, and they participate in regulating intestinal diseases in various ways. Probiotics are widely used as additives in livestock and the poultry industry and bring health benefits to hosts by improving intestinal microbes and growth performance, which provides more choices for promoting strong and efficient productivity. 相似文献
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Retroviruses comprise a large group of enveloped RNA viruses which have been found in a wide range of vertebrate species including fish. To date a number of fish retrovirus genomes have been partially or completely sequenced. Phylogenetic analysis and genome organization indicate a high diversity of fish retroviruses as well as some unique structural features that have not been found in any other retroviruses. Piscine retroviruses comprise both exogenous and endogenous viruses; most of them are associated with proliferative diseases. Because several of these proliferative diseases have a seasonal trend, they provide an excellent model for studying tumor development and regression. The aim of this work was to review the best-described fish retroviruses. 相似文献
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革兰氏阴性菌外膜蛋白研究进展 总被引：14，自引：0，他引：14
外膜蛋白对细菌本身和宿主都具有重要的作用。本文综述了革兰氏阴性菌外膜蛋白的组成、结构、功能及遗传调控,外膜蛋白可作为大肠杆菌的克隆标志,在细菌的致病机理及免疫机理中都有重要作用,研制开发外膜蛋白疫苗具有广阔的应用前景,必将为细菌性疾病的防治提供有力的措施。 相似文献
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Shuangshi Wei Xiaomei Liu Mingchun Gao Wenlong Zhang Yunhui Zhu Bo Ma Junwei Wang 《Research in veterinary science》2014
Interleukin-17 (IL-17 or IL-17A) is a proinflammatory cytokine produced by activated T cells. IL-17A plays important roles in inflammation and host defense. In this study, the cDNA of the goose IL-17A (GoIL-17A) gene was cloned from thymocytes. Recombinant GoIL-17A (rGoIL-17A) was expressed using a baculovirus expression system and then biologically characterized. The complete open reading frame (ORF) of GoIL-17A contains 510 base pairs that encode 169 amino acid residues, including a 29-amino acid signal peptide and a single potential N-linked glycosylation site. This protein has a molecular weight of 18.9 kDa. The amino acid sequence showed 95.9%, 84.6%, 45.0% and 38.4% similarity with the corresponding duck, chicken, rat, and human IL-17A sequences, respectively. The six conserved cysteine residues were also observed in GoIL-17A. A recombinant, mature form of GoIL-17A was produced and its biological activities in goose embryonic fibroblasts were investigated. RT-PCR analysis revealed a marked up-regulation of IL-6 and IL-8 mRNA expression in goose embryonic fibroblasts treated with 1–50 μg of rGoIL-17A for 12 h. The GoIL-17A gene sequence and the biologically active recombinant protein may be useful for understanding the role of IL-17A in immune regulation. 相似文献