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胚胎发育是生命过程中至关重要的环节之一,整个过程受到诸多因素影响。选择性剪切作为一种重要的调控机制,不仅影响胚胎发育中的结构变化,而且在细胞命运决定方面起着关键作用。选择性剪切调控是一个非常复杂的过程,然而对早期胚胎发育中选择性剪切的描述一直是有限的,选择性剪切仍面临着许多需要深入研究和未解决的问题。本文就目前已有的选择性剪切机制及调控元素进行综述,讨论选择性剪切在哺乳动物早期胚胎发育中的剪切作用和应用前景,如影响早期胚胎器官发育和组织分化,通过动态剪接体的变化控制体外全能/多能干细胞的转变等,为深入了解动物胚胎发育过程提供参考,并为未来针对人类胚胎或组织再生等研究提供理论基础。 相似文献
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《畜牧兽医科技信息》2017,(10)
<正>母猪胚胎发育的好坏及成活率直接关系到养猪业的成败。而猪胚胎发育的好坏又受诸多因素的影响,比如:排卵率、子宫空间、胎儿先天性缺陷、生殖激素、子宫感染和营养水平。猪胚胎死亡率受品种、遗传、胎次和环境条件的影响。因此,在饲养妊娠早期的母猪时,应注意提供优质饲料,以维持子宫内环境的正常,确保猪胚胎的正常发育,保障猪场的可持续发展。1影响胚胎发育的因素1.1排卵率在同一猪品种内,胚胎死亡率与排卵数有关,尤其当排 相似文献
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从屠宰场收集黄牛卵巢,取皮质深层卵母细胞进行体外成熟、体外受精和早期胚胎体外培养,分析了影响其效果的因素。结果表明,在成熟培养液中添加FSH(10IU/mL)、HCG(20IU/mL)和17β-E2(1mg/L)对卵母细胞受精后早期胚胎发育能力有极显著促进作用;等量牛卵泡液(BFF)与新生牛血清(NCS)对体外受精胚胎发育效果影响不显著,以15?F为宜;颗粒细胞与输卵管上皮细胞均能显著提高卵母细胞体外成熟受精后早期胚胎的发育率,颗粒细胞 输卵管上皮细胞对克服胚胎阻滞现象效果显著。 相似文献
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哺乳动物早期胚胎体外发育阻滞的产生与克服 总被引：3，自引：0，他引：3
哺乳动物早期胚胎发育阻滞是体外培养条件下普遍存在的现象。文中就离体情况下由于生长环境的变化使早期胚胎所遭受到外界因素的影响进行了探析。综合国内外研究报道，提出通过改善培养条件和利用体细胞共培养，克服早期胚胎的体外发育阻滞。旨在为哺乳动物胚胎的体外培养提供一些参考。 相似文献
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小鼠的早期胚胎发育是一个极为复杂而又受到精细调控的生命过程，包括卵母细胞成熟、受精和胚胎发育等顺序发生事件。可变剪接(alternative splicing, AS)是指将一个前体mRNA通过不同的剪接方式(选择不同的剪接位点组合)产生不同mRNA剪接异构体的过程。AS作为提高基因转录组复杂性和蛋白质多样性的关键因素，对于调控个体和胚胎的生长发育至关重要。现已有大量研究表明，AS在小鼠早期胚胎发育中起着至关重要的作用。本研究对AS在小鼠早期胚胎发育过程中作用的研究进展进行了综述，并着重介绍了相关剪接因子及其敲除影响胚胎发育的事件。 相似文献
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旨在对影响鹌鹑早期胚胎发育及性别分化的4个基因的表达进行研究。采用Wpkci基因和多重PCR鉴定鹌鹑早期胚胎的性别,在此基础上,选取早期胚胎发育不同时间点(3、4、5、6、7、8d)雌雄鹌鹑胚胎共120枚,其中雌雄各60枚,每个时间点10枚。采用Real-time PCR方法检测鹌鹑雌雄胚胎发育过程中不同时间点性别分化相关基因(3β-HSD、P-450c17、P450arom和ER)的表达,探讨了3β-HSD、P-450c17、P450arom和ER基因对鹌鹑早期胚胎发育及性别分化的影响。结果表明,鹌鹑胚胎P-450c17、P450arom和ER基因在鹌鹑胚胎发育的第4天雌性均高于雄性,其中P450arom基因仅在雌性胚胎中检测出有表达,且表达量在第4天达到最高峰(P<0.01),雄性胚胎整个发育过程中都无P450arom基因的表达;ER基因在鹌鹑胚胎发育第4天雌性显著高于雄性(P<0.05);P-450c17在鹌鹑胚胎发育第4天虽雌性高于雄性,但无显著性差异(P>0.05)。另外,3β-HSD在鹌鹑胚胎发育第5天达到其表达最高值,且雌性极显著高于雄性(P<0.01)。研究结果表明,3β-HSD、P-450c17、P450arom和ER基因在鹌鹑早期胚胎性别分化过程中起着重要的作用,尤其是在胚胎发育4～5d。 相似文献
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文章从卵母细胞的来源、精子体外获能、卵母细胞体外成熟、体外受精和体外受精早期胚胎培养五个方面综述了牛卵母细胞体外受精和体外成熟技术的研究进展.同时指出了影响精子体外获能的因素、影响卵母细胞成熟培养的因素、体外受精存在的问题及解决办法等.并且对影响该技术的主要因素进行了系统分析. 相似文献
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葡萄糖在牛体外受精及胚胎发育中的影响 总被引：4，自引：2，他引：2
在牛精子获能液中添加不同浓度的葡萄糖,应用体外培养技术对牛精子体外获能及早期胚胎发育进行研究,通过观察顶体反应、超激活、活率和早期胚胎发育率,筛选出获能液中最适葡萄糖浓度及其有利于牛早期胚胎发育的最佳浓度.结果表明:葡萄糖是精子获能和维持超激活运动的主要能源物质,其代谢过程中产生的活性氧在牛精子体外获能、受精过程中起重要作用,高浓度(超过9.15 mM)葡萄糖有利于获能的完成;但是对早期胚胎发育不利,对早期胚胎发育来说其最适添加量为6.10 mM,此时的囊胚率最高. 相似文献
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早期胚胎发育是现代生物技术的基础和重要环节之一,通过开设"牛早期胚胎发育观察"实验,可为学生掌握相关生物技术奠定基础。阐述了传统"牛早期胚胎发育观察"实验教学中存在的问题及相应的改革措施,以期提高该课程的实验教学质量,充分调动学生的实践主动性和创造性,提高学生的实验操作技能,培养应用型高素质创新人才。 相似文献
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U Besenfelder V Havlicek G Brem 《Reproduction in domestic animals = Zuchthygiene》2012,47(Z4):156-163
This review highlights the role of the oviduct in early embryo development, which has to fulfil many aligned and well-tuned tasks during early embryogenesis. The oviductal lining is subjected to dynamic changes to timely accomplish gamete transport, fertilization and embryo development and to deliver a competent and healthy conceptus to the endometrium which can implant and develop to term. Although knowledge about the role of the oviduct is limited, we know that embryos are very sensitive to the environment in which they develop. The success of in vitro embryo production techniques demonstrates that it is possible to bypass the oviduct during early development and, to a certain extent, replicate the conditions in vitro. However, comparative studies show that embryos developed in vivo are superior to their in vitro produced counterparts, underlining our relatively poor knowledge of the biology of the oviduct. Oviduct activity is orchestrated by various factors, depending on cyclic dynamics, which crucially affect the success of tubal transfer and/or (re-)collection of embryos in embryo transfer studies. This paper reviews data which demonstrate that in vivo culture of embryos in the bovine oviduct is a useful tool for the assessment of embryos developed under various conditions (e.g. superovulation vs single ovulation, lactating dairy cows vs non-lactating cows). It is concluded that more work in the field of early embryo development within the oviduct would contribute to improved ART protocols leading to healthy pregnancies and offspring. 相似文献
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胎盘是哺乳动物在妊娠期间胎儿和母体之间的联系枢纽,因此,胎盘发育是否正常在妊娠中起着关键的作用。Wnt信号通路在胚胎发育和胎盘形成的过程中有着重要的作用,作者通过回顾几条已经研究较为清楚的Wnt信号通路和牛早期胚胎和胎盘的形成过程,介绍了Wnt信号通路的组成部分在体细胞核移植（somatic cell nuclear transfer,SCNT）牛和正常人工授精的牛的胚胎早期表达,提出了DKK-1和Fzd4的表达对于早期胎盘形成和发育有特殊的作用。此外,抑制MAP2K和GSK3信号可以激活Wnt信号通路,增加内细胞团和滋养层细胞的数量,加速囊胚的发育。SCNT牛和正常人工授精的牛早期胎盘中E-cadherin和β-catenin蛋白的磷酸化程度相似,所以对于Wnt信号通路在牛胎盘的早期形成和发育中的作用还需进一步的了解和研究。 相似文献
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Placenta is the link between the fetus and the maternal body during pregnancy.Therefore, the pregnancy outcome of the key was related by the normal development of the placenta.Wnt signaling pathway plays an important role in the development of embryo and placenta formation, several Wnt pathways which have been clear study and the formation process of early embryo and placenta in cattle are reviewed in this article,the early expression of the Wnt pathway components in the somatic cell nuclear transfer (SCNT) cattle and normal insemination of bovine embryos is introduced. The expression of DKK-1 and Fzd4 have a special role in the formation and development of early placenta, but its molecular mechanism is not clear. In addition, the Wnt signaling pathway is activated by inhibiting the MAP2K and GSK3, led to the inner cell mass and trophoblast cell number increased and blastocyst development speed. But it is similar to the extent of phosphorylation of E-cadherin and beta-catenin protein in the early placenta of cows with SCNT and normal insemination, therefore, the role of Wnt signaling pathway in the early formation and development of bovine placenta should be further understood and studied. 相似文献
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Kim EY Lee JB Park HY Jeong CJ Riu KZ Park SP 《The Journal of reproduction and development》2011,57(3):346-354
Embryonic stem (ES) cells are expanded versions of the inner cell mass cells that compose the early mammalian blastocyst. Components derived from ES cells may contain various bioactive materials (BM) helpful for early preimplantation embryo growth. In this study, we examined the effect of human ES cell derived BM (hES-BM) on in vitro culture of bovine embryos. When bovine parthenogenetic day 2 embryos were cultured in 10% hES-BM, a significantly higher embryo development rate (44.3%) and increased cell numbers were observed relative to control medium containing 3 mg/ml BSA (19.5%; P<0.01). Among the various concentrations (5, 10 and 15%) and days of treatment (2 or 4 days) tested, 10% hES-BM treatment for 4 days provided the best culture environment to support the growth of bovine embryos in vitro (P<0.05). Little difference was observed between 10% hES-BM and 10% FBS treatment in the examined parthenogenetic or in vitro fertilized embryos, although the hES-BM group developed at a slightly better rate. However, the ICM cell numbers were significantly higher in the hES-BM group in irrespective of embryo origin (P<0.05). In addition, the relative levels of pluripotency (Oct4, × 1.8 fold; Nanog. × 3.3 fold), embryogenesis (Stat3, × 2.8 fold; FGF4, × 18.8 fold; E-cad, × 2.0 fold) and growth (Glut5, × 2.6 fold) genes were significantly higher in the 10% hES-BM group than in the 10% FBS group (P<0.05), while the levels of other genes (Bax, Bcl2, MnSOD and Connexin43) were not different. This is the first report examining the positive effects of hES-BM on bovine embryo development in vitro. Based on our results, we conclude that hES-BM can be used as a new protein supplement for bovine preimplantation embryo development. 相似文献