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Nhung Thi Nguyen Nguyen Xuan Bui Viet Linh Nguyen Van Khanh Nguyen Kazuhiro Kikuchi Hiep Thi Nguyen Hong Thi Nguyen Hoang Thinh Nguyen Quyen Van Dong Hoang Ha Chu Ngo Thi Kim Cuc Tamas Somfai 《Animal Science Journal》2020,91(1)
The Vietnamese Ban pig is a precious genetic resource that needs to be preserved. In vitro embryo production from in vitro matured (IVM) oocytes is an important tool for the utilization of cryopreserved porcine sperm. The aim of this study was to compare two media for the IVM of Ban pig oocytes. Immature oocytes were subjected to IVM either in a non‐defined (TCM‐199 + pig follicular fluid) or in a defined base medium (POM + epidermal growth factor). At the end of IVM, the oocytes were in vitro fertilized (IVF) with frozen Ban sperm. Ten hours after IVF, the oocytes were either subjected to orcein staining to check fertilization and maturation status or cultured in vitro for 7 days. There was no difference between the two IVM media in terms of percentages of oocyte maturation and blastocyst production. However, the percentage of male pronuclear formation after IVF and the total cell numbers in blastocysts were higher with the defined system. Zygotes obtained by the two IVM systems survived vitrification at similar rates. In conclusion, the two IVM systems were both effective for the production of Ban pig embryos; however, better embryo quality was achieved with the defined one. 相似文献
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Quynh A. Le Maki Hirata Nhien T. Nguyen Koki Takebayashi Manita Wittayarat Yoko Sato Zhao Namula Masahiro Nii Fuminori Tanihara Takeshige Otoi 《Animal Science Journal》2020,91(1)
This study was conducted to investigate the effect of seven concentrations of Cas9 protein (0, 25, 50, 100, 200, 500, and 1,000 ng/µl) on the development and gene editing of porcine embryos. This included the target editing and off‐target effect of embryos developed from zygotes that were edited via electroporation of the Cas9 protein with guide RNA targeting Myostatin genes. We found that the development to blastocysts of electroporated zygotes was not affected by the concentration of Cas9 protein. Although the editing rate, which was defined as the ratio of edited blastocysts to total examined blastocysts, did not differ with Cas9 protein concentration, the editing efficiency, which was defined as the frequency of indel mutations in each edited blastocyst, was significantly decreased in the edited blastocysts from zygotes electroporated with 25 ng/µl of Cas9 protein compared with that of blastocysts from zygotes electroporated with higher Cas9 protein concentrations. Moreover the frequency of indel events at the two possible off‐target sites was not significantly different with different concentrations of Cas9 protein. These results indicate that the concentration of Cas9 protein affects gene editing efficiency in embryos but not the embryonic development, gene editing rate, and non‐specific cleavage of off‐target sites. 相似文献
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借助于NIH生物信息中心Unigene里的数字差异显示软件平台,分析了猪植入前后早期胚胎发育9个EST文库的105 227个ESTs,筛选出了104个差异表达ESTs,对已知功能的差异表达基因进行GO分类分析,发现这些差异基因参与了广泛的生物功能和过程。同时,这些差异表达ESTs的聚类分析结果显示,体外和体内发育的囊胚基因表达存在较大的差异。对这些差异表达ESTs表达模式的分析结果显示,猪植入前早期胚胎发育阶段基因呈振荡模式表达,其中线粒体和核糖体相关基因的表达在囊胚中的表达丰度要明显高于其他阶段。表达数字差异显示的结果能为猪早期胚胎发育机理的研究提供线索。 相似文献
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鸡胚外泌体miRNAs功能分析 总被引:2,自引:1,他引:1
旨在基于鸡胚外泌体及所含有的miRNAs解析其产生生理功效的活性物质基础及作用机制。本研究收集13胚龄惠阳胡须鸡胚蛋18枚(3组,每组6枚),采用酶消化、蔗糖密度梯度和差速超速离心等方法分离鸡胚组织来源的外泌体,经透射电镜、纳米流式和标志蛋白流式检测等方法鉴定其特征。利用高通量测序方法研究外泌体样本中miRNAs表达谱,对各样本top 10且共表达的miRNAs进行靶基因预测与功能分析。结果表明,分别获得了3个浮力密度范围(S1:1.13 g·mL-1、S2:1.21 g·mL-1和S3:1.32 g·mL-1)具有外泌体典型特征的胞外囊泡;与miRBase V21进行比对发现,S1、S2和S3样品中分别含有675、661和845个已知的miRNAs,这些miRNAs中有488个(52.6%)三者共有,包括了广泛参与细胞增殖、分化和免疫应答等过程的功能性miRNAs。TargetScan 7.2和miRDB预测得到3个样本中top 10且共表达的56个miRNAs的靶基因,获得的3 650个靶基因经DAVID分析,显著富集了24个与机体生长、发育、免疫等有关的生物学通路(P<0.05),包括MAPK信号通路、mTOR信号通路、Notch信号通路、Wnt信号通路和GnRH信号通路等。本研究建立了鸡胚组织中有效分离外泌体的方法,发现鸡胚组织来源的外泌体miRNAs会影响机体生长发育和免疫调节有关的生物学通路。 相似文献
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小麦转化受体体系的建立--小麦幼胚组织培养研究 总被引:1,自引:0,他引:1
建立了一个以小麦幼胚为转化受体,转化后快速成苗的体系.筛选出适合于不同小麦品种的愈伤组织诱导培养基MS+2mg·L-1 2,4-D+0.4mg·L-1 IAA+0.2mg·-1 KT,愈伤诱导率达94.87%~99.04%.幼胚接种后,暗处理与弱光、强光合理配置利于绿芽的快速形成,在分化培养基中添加2.0g·L-1活性炭或1mg·L-1多效唑利于小麦再生苗的正常生长,从而提高移栽成活率. 相似文献
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21个小白菜品种小孢子培养结果表明:适宜的花蕾长为2.5~3.5mm,花瓣与花药长度比为1/2~3/4;0.05~0.10 mg.L-1的细胞分裂素能促进小孢子胚的发生,高于此浓度的细胞分裂素对小孢子胚的产生有抑制作用,并使小孢子胚向畸形化发展;0.05mg.L-16-BA 0.10 mg.L-1NAA的配比可以明显提高成熟胚的比例。 相似文献