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以50~60日龄的Holstein奶牛胎儿原始生殖嵴组织为材料,通过RT-PCR的方法克隆奶牛Nanog与Lin28基因开放性阅读框(ORF)全序列。序列全长分别为903 bp和618 bp。所克隆的奶牛Nanog与Lin28基因序列与GenBank中已经发表的参考序列进行比对同源性均为100%。将扩增的基因片段经过酶切后亚克隆到反转录病毒载体pMSCVneo的多克隆位点,经过酶切、PCR和测序鉴定正确后,应用lipofectamine2000介导转染PT67包装细胞,经过14 d G418连续抗性筛选,挑选抗性集落扩大培养。收集病毒上清经过RT-PCR与透射电镜检测,并用NIH3T3细胞测定病毒滴度。结果表明,病毒上清中含有逆转录病毒颗粒,Nanog与Lin28基因在筛选后的包装细胞PT67细胞中均有转录,病毒上清感染滴度值分别达到7.5×107cfu/mL和9.19×107cfu/mL。结果表明,本试验已经成功克隆出奶牛Nanog与Lin28基因开放性阅读框全序列,并建立高效、稳定产生包含有pMSCV-Nanog与pMSCV-Lin28质粒的感染性病毒颗粒的包装细胞株,为进一步产生奶牛诱导性多能干细胞(Induced pluripotentstem cells,iPSCs)奠定基础。 相似文献
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[目的]旨在通过构建秦川牛丙酮酸脱氢酶β亚基(Pyruvate dehydrogenase β subunit,PDHB)基因的重组腺病毒载体,为研究PDHB基因在牛前体脂肪细胞分化过程中的功能做准备。[方法]根据牛PDHB基因mRNA序列(GenBank Accession No.NM_001035435)设计引物,克隆该基因的编码区(Coding Sequence, CDS)序列。测序验证后将其重组到穿梭载体pAdTrack-CMV上,经PmeⅠ线性化后,转化到含有pAdEasy-1腺病毒骨架载体的E. coli BJ5183感受态细胞中进行同源重组,以获得重组质粒pAd-PDHB。再将经PacⅠ酶切线性化的pAd-PDHB转染到HEK 293A细胞中,进行病毒包装并扩增高滴度病毒Ad-PDHB,绿色荧光蛋白(GFP)标记法测定病毒滴度。将高浓度的Ad-PDHB病毒感染牛肌内前体脂肪细胞,实时荧光定量PCR(qRT-PCR)检测PDHB的表达量。[结果]经测序验证,本实验克隆获得的牛PDHB基因CDS与数据库GenBank收录的序列一致。将PDHB基因CDS与穿梭载体pAdTrack-CMV重组并转染HEK 293A细胞后成功获得了重组腺病毒Ad-PDHB,其滴度为1.66×109 PFU.mL-1。腺病毒Ad-PDHB侵染牛肌内前体脂肪细胞后,PDHB在mRNA的表达水平比对照组高25.5倍。[结论]成功克隆了秦川牛PDHB基因并构建了重组腺病毒质粒pAd-PDHB,并获得能够在牛肌内前体脂肪细胞中过表达PDHB基因的高滴度重组腺病毒Ad-PDHB。 相似文献
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根据口蹄疫病毒的感染特征及其在临床发病过程中呈现的症状,筛选抗口蹄疫病毒单链抗体基因。通过EcoRⅠ/NotⅠ双酶切中间质粒pGEX-ScFv获得单链抗体基因片段,并克隆至反转录病毒载体质粒pFB-neo,构建反转录病毒穿梭载体质粒pFB-ScFv。将pFB-ScFv与辅助质粒pVPack-GP、pVPack-10A1共转染HEK293T细胞,包装重组反转录病毒MMLV-ScFv。同时,构建含增强型绿色荧光蛋白基因的重组反转录病毒MMLV-EGFP作为对照。利用所包装重组反转录病毒感染猪成纤维细胞,通过G418筛选获得携带目的基因的单克隆细胞集落。试验结果表明,本试验在成功构建反转录病毒穿梭载体pFB-ScFv和pFB-EGFP的基础上,获得了分别携带抗口蹄疫病毒单链抗体基因和增强型绿色荧光蛋白基因的反转录病毒,并最终筛选出分别携带上述基因的猪成纤维细胞克隆,为抗口蹄疫病毒转基因动物的研究奠定了基础。 相似文献
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通过研究慢病毒介导的RNA干扰靶向新城疫病毒P基因抑制其在鸡胚成纤维细胞上的复制,从而为新城疫病毒的抗病毒研究奠定基础。①针对NDVP基因设计siRNA干扰序列,构建慢病毒（lentivirus）介导的RNAi重组载体;②携带有siRNA表达元件重组慢病毒包装及其滴度测定;③包装后重组慢病毒接种CEF细胞并接毒NDV,48h分别进行Realtime RT-PCR和NDV滴度测定,并观察细胞病变情况。结果表明,本研究针对NDVNA-1株P基因2个RNAi靶位（位于开放阅读框的641和827位）设计的RNAi641和RNAi-827,对病毒复制具很强的抑制效果,且641位的重要性大于827位． 相似文献
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分子伴侣Jiv90基因的克隆及其在猪脐静脉血管内皮细胞中的表达 总被引：1，自引：0，他引：1
为研究分子伴侣Jiv90对猪瘟病毒复制的影响,克隆了分子伴侣Jiv90基因,构建了真核表达载体并在猪脐静脉血管内皮细胞中表达。根据牛的Jiv90基因序列和真核表达载体pEGFP-C1设计引物,经PCR扩增,成功克隆到猪Jiv90基因,回收后与pEGFP-C1载体连接,构建重组表达载体pEGFP-C1-Jiv90,提取质粒并采用脂质体法转染猪脐静脉血管内皮细胞。转染24 h后,荧光显微镜下可见绿色荧光蛋白表达,经G418抗性筛选得到阳性克隆。本研究成功构建了pEGFP-C1-Jiv90真核表达载体,得到稳定表达Jiv90的细胞株,为今后开展分子伴侣对猪瘟病毒复制影响的研究奠定了基础。 相似文献
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旨在构建并包装打靶绵羊MSTN基因的位点特异性锌指核酸酶腺病毒表达载体,以借助腺病毒的高转染效率和非整合性以及锌指核酸酶的高效性和特异性实现对绵羊MSTN基因的敲除。本研究利用PCR扩增T2A序列和锌指核酸酶异源二聚体序列,测序鉴定后依次克隆至pAdTrack-CMV,得到pAdTrack-ZFNL-T2A-ZFNR穿梭载体,将之与腺病毒骨架载体pAdEasy-1共转染至BJ5183菌株进行同源重组,以构建pAdEasy-ZFNL-T2A-ZFNR表达载体。然后用上述表达载体转染HEK293细胞进行重组腺病毒的包装,将PCR鉴定阳性的病毒进行扩增并测定病毒滴度。侵染绵羊胎儿成纤维细胞检测重组腺病毒对靶细胞的侵染能力,并用Western blot方法检测绵羊胎儿成纤维细胞中ZFN的表达,进而在细胞水平验证ZFN的活性。结果,包装得到的锌指核酸酶重组腺病毒能够高效侵染绵羊胎儿成纤维细胞并表达ZFN,腺病毒介导的ZFN可识别并切割绵羊MSTN基因。本研究成功获得靶向识别并切割绵羊MSTN基因的锌指核酸酶重组腺病毒。 相似文献
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为研制马传染性贫血病毒(EIAV)标记疫苗株,本研究在EIAV驴胎皮肤(FDD)细胞弱毒疫苗株感染性克隆pEIAVFDDV3-8的S2基因内部引入两个终止密码子,致使S2基因终止表达,构建了一株S2基因突变的感染性克隆pEIAVFDDV3-8△S2。用该重组质粒转染FDD细胞,盲传至第4代时,转染细胞病变明显,电镜下可见细胞内的典型病毒颗粒。反转录酶活性检测和Real-time PCR对病毒拷贝数的检测均证明,获得了EIAVS2基因终止表达的感染性克隆毒株,命名为EIAVFDDV3-8△S2。 相似文献
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本研究旨在通过构建西农萨能羊脂肪酸合酶(FASN)基因乙酰/丙二酸单酰基转移酶(MAT)区域的重组腺病毒载体,为研究其在奶山羊乳腺上皮细胞中过表达以及功能和作用机制做准备。根据GenBank收录的西农萨能羊MAT序列设计引物,PCR扩增并克隆测序。将目的基因连接到穿梭载体pAdTrack/CMV上并线性化后,转化含有腺病毒骨架载体pAdEasyⅠ的E.coli Bj5183感受态细胞进行同源重组,得到重组腺病毒质粒pAd-MAT-HIS,并用PacⅠ酶切鉴定,将经过PacⅠ线性化的pAd-MAT-HIS转染HEK 293细胞进行病毒包装和扩增,用LaSRT法测定病毒滴度。将本次克隆的MAT序列与GenBank收录的山羊序列对比发现,在601bp处碱基由G转变为A,导致氨基酸序列由丙氨酸(Ala)201转变为苏氨酸(Thr)201。酶切鉴定、绿色荧光蛋白观察、PCR及Western blot检测均证明,重组腺病毒质粒构建成功,病毒滴度为2×109 PFU.mL-1。本研究成功构建了重组腺病毒pAdEasy-MAT-HIS。 相似文献
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《中国畜牧杂志》2015,(3)
构建冷诱导RNA结合蛋白(CIRP)过表达慢病毒载体,并对其进行病毒包装、鉴定与滴度测定,为进一步研究CIRP功能提供基础工具。本研究从4℃冷处理8 h的SD大鼠睾丸组织中获得CIRP的cDNA序列测序后,将其克隆入LV5质粒中,经双酶切及测序鉴定;利用脂质体将鉴定的阳性重组LV5-cirp表达载体与pGag/Pol、pRev、pVSV-G 3个质粒共转染到HEK-293T细胞,72 h收获上清,包装产生慢病毒。将所得病毒悬液梯度稀释后感染293T细胞,检测病毒滴度,以及采用Western blot方法验证基因表达情况。结果表明:经琼脂糖凝胶电泳鉴定、PCR鉴定、酶切及测序结果证明成功构建了LV5-cirp重组质粒,序列比对与设计序列符合率100%,并成功包装成慢病毒,病毒滴度为6.30×108TU/m L;将制备成功的CIRP慢病毒过表达载体感染293T细胞后,Western blot检测结果显示细胞中CIRP蛋白表达水平显著高于正常细胞以及慢病毒阴性对照组(P0.01)。本实验成功构建CIRP慢病毒过表达载体并完成了慢病毒包装及滴度的测定,为今后的研究提供了基础工具。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献