Impairments in embryonic genome activation in rhesus monkey somatic cell nuclear transfer embryos
Impairments in embryonic genome activation in rhesus monkey somatic cell nuclear transfer embryos
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DOI：
10.1089/clo.2007.0040
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发表时间：
2008-03-01
期刊：
影响因子：
--
通讯作者：
Ji, Weizhi
中科院分区：
文献类型：
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作者：
Niu, Yuyu;Yang, Shihua;Ji, Weizhi
体细胞核转移（Somatic cell nuclear transfer， SCNT）是一个显著的过程，在这个过程中，体细胞核受卵浆的作用，其机制目前尚不清楚。本研究表明，与体外受精（IVF）胚胎的发育能力（42.1%）相比，SCNT胚胎的发育能力（%囊胚）明显受损（p < 0.05）。SCNT胚胎在胚胎发育的时间过程中也存在异常。SCNT产生的胚胎比体外受精产生的胚胎更快地进入8细胞阶段。我们通过RT-PCR比较了5种核仁相关蛋白——核仁蛋白、核磷蛋白、纤维蛋白、PAF53和ubf在单试管婴儿和SCNT囊胚中的转录模式。SCNT胚胎显示基因转录异常。在8细胞和16细胞SCNT胚胎中检测不到纤维蛋白的免疫定位，这表明SCNT产生的猴胚胎的胚胎基因组激活比体外受精产生的胚胎延迟。一些SCNT胚胎表现出相对较高的发育潜力和纤维蛋白表达，通过长时间暴露于细胞核细胞质。因此，我们的数据表明SCNT胚胎的特征是卵裂异常和胚胎基因组转录的及时开始，这些缺陷可能解释了它们在植入前和植入后发育能力的降低。
Somatic cell nuclear transfer (SCNT) is a remarkable process in which a somatic cell nucleus is acted upon by the ooplasm via mechanisms that today remain unknown. Here we show the developmental competence (% blastocyst) of embryos derived from SCNT (21%) was markedly (p < 0.05) impaired compared with those derived from in vitro fertilization (IVF) (42.1%) in rhesus monkey. Also, SCNT embryos were abnormal in their time course of embryonic development. SCNT produced embryos reached the eight-cell stage faster than did IVF produced embryos. We compare the transcription patterns of five nucleolar-related proteins-nucleolin, nucleophosmin, fibrillarin, PAF53, and UBF-in single IVF and SCNT blastocysts by RT-PCR. The SCNT embryos showed abnormal gene transcription. Immunolocalization of fibrillarin was undetectable in 8-cell and 16-cell SCNT embryos, indicating embryonic genomic activation was delayed in monkey embryos produced by SCNT compared to their IVF-derived counterparts. Some of SCNT embryos appeared to relative higher developmental potential and fibrillarin expression by prolonged exposure of incoming nuclei to a cytoplasm. Thus, our data show that SCNT embryos are characterized by abnormal cleavage and the timely onset of embryonic genome transcription, deficits that may explain their reduced pre- and postimplantation developmental capacity.