核克隆和基因组的表观遗传重编程
W M Rideout1, K Eggan, R Jaenisch
1Whitehead Institute for Biomedical Research and, Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.
概括
通过核转移 (NT) 克隆哺乳动物经常由于表观遗传重编程错误而失败. 来自干细胞的克隆胚胎比来自体细胞的胚胎更好,但有些表观遗传信息无法恢复,影响了发育.
科学领域:
- 生殖生物学 生殖生物学
- 发育生物学是发展生物学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 哺乳动物的核转移 (NT) 成功率很低,导致发育失败.
- 克隆哺乳动物的异常通常与不完整的表观遗传重编程有关.
研究的目的:
- 研究捐赠细胞类型对克隆哺乳动物表观遗传重编程和发育结果的影响.
- 确定核转移后表观遗传修复的局限性.
主要方法:
- 从胚胎干细胞获得的克隆胚胎与体细胞进行比较.
- 对表观遗传标记的分析,包括端粒长度和X染色体不活化.
- 克隆胚胎的发育进展和生存率的评估.
主要成果:
- 从胚胎干细胞克隆的胚胎显示出与体细胞克隆相比,植入后发育的改善.
- 虽然可以重新编程端粒长度和X染色体不活化,但游戏印记无法恢复.
- 在克隆哺乳动物中发生了显著的转录失调,但它们可以长期生存.
结论:
- 表观遗传重编程对于成功的哺乳动物克隆至关重要,捐赠细胞的选择会影响结果.
- 哺乳动物的发育表现出对表观遗传异常的耐受性,直到一定值.
- 游戏印记的不完全恢复是核转移技术的一个关键局限性.
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