在克隆小鼠胚胎中X染色体不活化
K Eggan1, H Akutsu, K Hochedlinger
1Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.
概括
克隆重置鼠标胚胎X染色体上的表观遗传标记. 该研究表明,在克隆过程中,表观遗传标记可以被移除和恢复,从而影响X染色体无活化模式.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 发展生物学 发展生物学
- 生殖科学 生殖科学
背景情况:
- 在女性体细胞中的两个X染色体之间存在表观遗传差异.
- 在雌性哺乳动物中,X染色体无活化 (XCI) 是剂量补偿的关键过程.
- 了解克隆过程中的表观遗传重编程对于发育生物学至关重要.
研究的目的:
- 为了研究克隆是否会重置体质女性核中的两个X染色体之间的表观遗传差异.
- 分析克隆小鼠胚胎中的X染色体失活模式.
- 为了比较体内XCI与体内XCI之间,在体育生殖过程中施加的表观遗传标记.
主要方法:
- 在克隆小鼠胚胎中监测X无活化.
- 利用体细胞和胚胎干细胞作为核捐赠体.
- 分析胚胎本身和托菲克托皮 (TE) 中的X无活化模式.
主要成果:
- 在克隆胚胎的分裂过程中,X染色体都活跃.
- 随机X无活化发生在胚胎本身.
- 在托菲克托皮 (TE) 中观察到非随机X无活化,捐赠者的无活性的X被优先无活化.
- 在使用胚胎干细胞时,在TE和胚胎中观察到随机X无活化.
结论:
- 在克隆过程中,X染色体上的表观遗传标记可以被删除并重新建立.
- 克隆可以在X染色体上重置和重新施加表观遗传标记.
- 在TE中印制XCI的体质生成过程中建立的表观遗传标记在功能上与体质XCI过程中建立的标记相当.
相关概念视频
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The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.


