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11.
During fertilization in mammalian species, a sperm-induced intracellular Ca2+ signal ([Ca2+]i) mediates both exit of meiosis and oocyte activation. Recently, we demonstrated in mouse oocytes that the phosphorylation levels of inositol 1,4,5 trisphosphate receptor type1 (IP3R1), the channel responsible for Ca2+ release and oscillations during fertilization, changed during maturation and fertilization. Therefore, we examined the expression and phosphorylation of IP3R1 during in vitro maturation of pig oocytes. Here, our present study shows that expression of IP3R1 protein did not change during maturation, although the phosphorylation status of the receptor, specifically at an MPM-2 epitope, did. We found that while at the beginning of maturation IP3R1 lacked MPM-2 immunoreactivity, it became MPM-2 reactive by 24 h and reached maximal reactivity by 36 h. Interestingly, the acquisition of MPM-2 reactivity coincided with the activation of p34cdc2 kinase and mitogen-activated protein kinase (MAPK), which are involved in meiotic progression. Following completion of maturation, inactivation of MAPK by U0126 did not affect IP3R1 phosphorylation, although inactivation of p34cdc2 kinase by roscovitine dramatically reduced IP3R1 phosphorylation. Neither inhibitor affected total expression of IP3R1. Altogether, our results show that IP3R1 undergoes dynamic phosphorylation during maturation and this might underlie the generation of oscillations at fertilization.  相似文献   
12.
Unfertilized oocytes are one of the most desired germ cell stages for cryopreservation because these cryopreserved oocytes can be used for assisted reproductive technologies, including in vitro fertilization (IVF) and intracytoplasmic sperm injection. However, in general, the fertility and developmental ability of cryopreserved oocytes are still low. The aim of the present study was to improve vitrification of mouse oocytes. First, the effects of calcium and cryoprotectants, dimethyl sulfoxide and ethylene glycol (EG), in vitrification medium on survival and developmental ability of vitrified oocytes were evaluated. Oocytes were vitrified by a minimal volume cooling procedure using different cryoprotectants. Most of the vitrified oocytes were morphologically normal after warming, but their fertility and development were low independently of calcium and cryoprotectants. Second, the effect of cumulus cells on ability of oocytes to be fertilized and develop in vitro was examined. The fertility and developmental ability of denuded oocytes (DOs) after IVF were reduced compared with cumulus-oocyte complexes (COCs) both in fresh and cryopreserved groups. Vitrified COCs showed significantly (P<0.05) higher fertility and ability to develop to the 2-cell and blastocyst stages than those of vitrified DOs with cumulus cells and vitrified DOs alone. The vitrified COCs developed to term at a high success rate equivalent to the rate obtained with IVF using fresh COCs. Taken together, the current results clearly demonstrate that, in the presence of surrounding cumulus cells, matured mouse oocytes vitrified using calcium-free media and EG retain their developmental competence. These findings will contribute to improve oocyte vitrification in not only experimental animals but also clinical application for human infertility.  相似文献   
13.
利用RACE和RT-PCR技术,从香蕉中克隆出编码RuBPCase小亚基的全长cDNA,并与GenBank中已经报道的其他部分香蕉bcS基因的核苷酸和推导的氨基酸序列进行同源性分析,为进一步研究香蕉RUBPCase 的功能与结构提供依据。  相似文献   
14.
旨在利用覆盖全基因组和性状的特异性SNPs标记预测和牛、西门塔尔牛与荷斯坦牛杂种优势,为牛杂种优势利用和选种选配提供参考依据。本研究分别利用牛Illumina Bovine HD 770 K和GGP Bovine 100 K芯片对464头和牛、1 222头西门塔尔牛和43头荷斯坦牛3个亲本群体进行基因型分型,并通过牛QTLs数据库筛选与目的性状对应的QTLs,对比牛参考基因组映射得到与初生重、周岁重、胴体重性状相关的特异性SNPs;然后构建覆盖全基因组和性状特异性SNPs两种标记状态同源矩阵,通过计算杂交组合亲本间的遗传距离来预测品种间杂种优势,并利用配合力分析验证较优组合的实际杂交效果。结果表明,基于全基因组和性状特异性SNPs计算的各杂交组合遗传距离差异不显著。在全基因组水平上,西门塔尔牛♂×荷斯坦牛♀(S×H)与和牛♂×荷斯坦牛♀(W×H)亲本间杂交组合遗传距离分别为0.346 1和0.338 9;在初生重、周岁重和胴体重性状上,S×H亲本间遗传距离分别为0.343 1、0.348 7和0.336 7,而W×H遗传距离分别为0.337 6、0.340 7和0.329 2;两种SNPs标记计算的遗传距离均为S×H较大,W×H次之。因此,在初生重、周岁重、胴体重性状上,S×H为较优杂交组合。通过分析德系西门塔尔牛♂×荷斯坦牛♀实际杂交群体的配合力,发现10个父系在初生重性状上一般配合力和特殊配合力均为正效应,最高效应值分别达到3.760 9和8.931 2。西门塔尔牛与荷斯坦牛杂交可在初生重、周岁重和胴体重获得较高的杂种优势。  相似文献   
15.
贵州省具有发展草食畜禽的优越条件,从省情出发,研究了贵州省养猪的最大承载量,研究了贵州自然条件、草食畜禽品种资源和饲料资源,研究了发展草食畜禽的潜力与措施,提出了贵州主要畜禽发展指标等。  相似文献   
16.
To determine the genotypes of Giardia intestinalis from domestic and wild animals in Japan, Giardia isolates obtained from feces of 24 dogs kept in households and breeding kennels, three companion cats, five dairy calves and three wild monkeys, Macaca fuscata, were genotyped using the 177 bp sequence of the glutamete dehydrogenase gene (gdh). The genotypes were assemblages A, C, D or A/D for dog isolates, Assemblage F for cat isolates, assemblages A or E for calf isolates and assemblage B for monkey isolates. This is the first report on the genotypes of Giardia isolates from cats, calves and wild monkeys in Japan.  相似文献   
17.
中国西门塔尔牛育种效果分析   总被引:1,自引:0,他引:1  
采用6个国家级种畜场1980~2000年间的数据对中国西门塔尔牛21年来的育种效果进行分析。对主要性状的遗传力、遗传相关进行了估计.并计算出总性能指数。所有性状均采用动物模型并利用MT-DFREML(多性状非求导)软件进行分析。  相似文献   
18.
三角状五肽(PPR)蛋白作为一类靶向定位于半自主细胞器的序列特异性RNA结合蛋白,在植物的生长发育过程中具有重要的作用.本研究基于茶树基因组数据,利用生物信息学方法对茶树CsPPR基因家族进行系统鉴定,并对其蛋白质理化性质、结构域保守性、亚细胞定位、基因结构、染色体定位与分布等进行了分析.结果表明,在茶树基因组数据中共...  相似文献   
19.
Fisheries Science - Gene expression profiles during the transition from fasting to refeeding were investigated in the gut and liver of Masu salmon Oncorhynchus masou masou. Fish were starved for...  相似文献   
20.
Increased hepatic metabolism of estradiol may cause weakened estrous behavior in lactating dairy cows, but this hypothesis must be examined further, especially through diachronic study of the hepatic estradiol-17beta glucuronidation activity of uridine diphosphate (UDP)-glucuronosyltransferases. Therefore, in order to develop a new tool for this purpose, we attempted to conduct biopsy of the livers of dairy cows with the aid of ultrasonography and to measure the UDP-glucuronosyltransferase activities of microsomes of the specimens using in vitro glucuronidation followed by HPLC analysis. We were able to measure the activities of the microsomes prepared from the liver biopsy, and the results seemed reliable. Therefore, this method may become a new tool in clinical studies to detect estradiol-17beta glucuronidation activity.  相似文献   
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