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《畜牧与兽医》2017,(6):83-86
斑马鱼是研究人类疾病的重要动物模型,基因组定点编辑技术在利用斑马鱼研究同源基因功能方面提供了简便高效的途径。利用CRISPR/Cas9系统,在斑马鱼TU品系第5号染色体中选择靶位点,将Cas9 mRNA、靶位点识别的sgRNA和带有同源重组臂、利用短链肌球蛋白(Mylz2)启动子启动的绿色荧光蛋白(eGFP)基因显微注射到斑马鱼受精卵中,获得在该位点定点插入外源基因,并在肌肉中特异表达绿色荧光蛋白的转基因斑马鱼。利用基因组DNA的PCR扩增,结合激发光下斑马鱼胚胎荧光表达情况,在存活的87尾幼鱼中发现其中45尾有荧光表达,同源重组率为51.724%。研究表明,利用CRISPR/Cas9系统成功定点插入外源基因,并获得在肌肉中特异性表达绿色荧光的斑马鱼。 相似文献
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本研究应用Illumina Hiseq 2000测序系统对副猪嗜血杆菌(HPS)血清4型gx033株进行全基因组序列测定,经过DNA文库构建、测序、数据过滤和组装,绘制了全基因组草图.全基因组草图显示,HPS血清4型的基因组大小为2 155 493 bp,G+C含量为39.79％,含有编码基因2 189个,基因总长度1 881 801 bp.基因功能注释表明,849个基因功能尚不明确,1 340个基因被分为能量产生和转化、转录和细胞周期调控等19个功能组.该HPS血清4型全基因组草图的绘制为HPS病的致病机制等研究提供依据. 相似文献
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随着人类和很多动物的基因组测序完成,以基因组功能研究为主要目标的后基因组时代的来临,基因功能信息的获取将成为基因研究的重点.基因差异表达分析是获取基因功能信息的重要方法. 相似文献
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马立克病毒(Marek′s disease virus,MDV)是一种高致瘤性α-疱疹病毒,基因组为166～184 kb的线状双股DNA,同时因为其严格的细胞结合性特点,如何分离纯化病毒DNA,一直阻碍人类对MDV的研究.常规方法制备的病毒基因组中含有大量的细胞基因组,不利于高效转染.通过密度梯度离心法从宿主细胞中分离MDV DNA,由于MDV DNA的浮密度与宿主细胞基因组相近,所以制备时也有细胞DNA的污染[1-2].Robin等用脉冲电泳的方法分离MDV基因组[3],虽然完全去除了宿主细胞基因组,但是这种方法对设备和技术要求都较高,所以没有得到推广.因此发展一种新的提取纯化MDV基因组方法对于MDV的分子生物学研究至关重要. 相似文献
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多细胞生物在发育的特定时期、特定组织中的表达某些基因.如果这些基因表达调控受到干扰则可能对机体产生有害的影响,而这对于寄生虫病来说则是一种潜在的控制其发病的新机制.目前有关寄生虫尤其是蠕虫基因的调控机制及其转录因子方面的研究报道并不多见,这主要由于蠕虫等生活周期比较复杂且缺乏合适的体外转化体系.Cae-norhabditis elegans,简称C.elegans,中文名秀丽隐杆线虫,又称为华美广杆线虫、秀丽新小杆线虫,是一种在土壤中自由腐生的线虫.1974年,英国科学家Sydney Brenner开创性地以C.elegans为材料用于揭示动物细胞凋亡的分子机制[1].目前这种美丽的小线虫已经应用于现代发育生物学、遗传学和基因组学等多种生物研究领域,成为重要模式生物之一[2].1999年,Britton等率先将C.elegans用于寄生虫启动子组织特异性的表达研究[3].近年来,国内外许多科学家已经在将C.elegans作为研究寄生虫基因功能的模式生物方面进行了积极的探讨[4-5],此外,C.elegans在其他领域方面的应用为防治寄生虫病提供重要的参考依据. 相似文献
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利用鸡胚模型进行基因功能研究的技术和方法 总被引：2，自引：1，他引：1
鸡胚作为经典的胚胎生物学模型被用来研究发育学现象几十年前就有报道.随着新的技术手段的发明和鸡的基因组序列的完善,鸡胚又重新成为了研究发育过程中重要基因功能的模型.基因功能获得和缺失是研究基因功能的重要手段.本文讨论了可以在胚胎发育早期调整基因功能的转基因技术和方法. 相似文献
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为了研究对乙酰氨基酚对斑马鱼发育影响,采用高通量转录组测序RNA-seq技术对对乙酰氨基酚处理组(CAPAP组)与对照组(CO组)斑马鱼进行检测,以斑马鱼基因(danio rerio assembly version GRCz10)作为参考基因组,对检测结果进行拼接与质量评估,筛选出差异表达基因,并进行GO和Pathway功能分析。荧光定量PCR对部分与肝脏有关的差异表达基因进行验证。结果表明,CO与CAPAP组的差异表达基因数量为72个,其中上调差异表达基因40个,下调差异表达基因32个。对CO与CAPAP组差异表达基因进行GO富集分析,上调基因主要富集于47个条目中,下调基因主要富集于16个条目中,这些基因涉及生物进程和分子功能等多种生物活性方面,说明对乙酰氨基酚对斑马鱼的发育有一定的影响。 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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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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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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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
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 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