Prather R S, Rickords L F
Department of Animal Sciences, University of Missouri-Columbia 65211.
Mol Reprod Dev. 1992 Oct;33(2):119-23. doi: 10.1002/mrd.1080330202.
The appearance and stabilization of a core protein epitope of the snRNP is developmentally regulated during pig embryogenesis. The epitope recognized by the monoclonal antibody Y12 is present in the germinal vesicle of mature oocytes and interphase nuclei of late 4-cell stage (24 to 30 hours post cleavage to the 4-cell stage) to blastocyst stage embryos. There was no antibody localization within pronuclei, or nuclei of 2-cell or early 4-cell stage embryos. Zygotes or 2-cell stage embryos cultured in the presence of alpha-amanitin to the late 4-cell stage showed no immunoreactivity, whereas control embryos had immunoreactivity. Thus antibody localization was correlated with RNA synthesis and RNA processing that begins by 24 hours post cleavage to the 4-cell stage. A final experiment showed no detectable immunoreactivity in 16-cell stage nuclei that had been transferred to enucleated activated meiotic metaphase II oocytes. Since immunoreactivity is associated with active RNA synthesis and RNA processing, it suggests that the 16-cell stage nucleus, which is RNA synthetically active, does not process RNA after nuclear transfer to an enucleated activated meiotic metaphase II oocyte.
在猪胚胎发生过程中，小核核糖核蛋白（snRNP）核心蛋白表位的出现和稳定是受发育调控的。单克隆抗体Y12识别的表位存在于成熟卵母细胞的生发泡以及4细胞晚期（卵裂至4细胞期后24至30小时）至囊胚期胚胎的间期细胞核中。在原核、2细胞或4细胞早期胚胎的细胞核内未发现抗体定位。在α-鹅膏蕈碱存在的情况下培养至4细胞晚期的合子或2细胞期胚胎无免疫反应性，而对照胚胎有免疫反应性。因此，抗体定位与卵裂至4细胞期后24小时开始的RNA合成和RNA加工相关。最后一项实验表明，转移至去核激活的减数分裂中期II期卵母细胞中的16细胞期细胞核未检测到免疫反应性。由于免疫反应性与活跃的RNA合成和RNA加工相关，这表明具有RNA合成活性的16细胞期细胞核在转移至去核激活的减数分裂中期II期卵母细胞后不进行RNA加工。
