删除一个进化保守的TAD边界影响小鼠†中的精子生成
Ana C Lima1, Mariam Okhovat2, Alexandra M Stendahl1
1Division of Genetics, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, OR 97006, USA.
Biology of reproduction
|February 4, 2025
概括
破坏拓相关域边界的非编码突变损害了小鼠的精子生成,减少了精子的生产. 然而,男性生育能力不受影响,这表明非编码变异可能比编码突变的影响小.
科学领域:
- 遗传学和表观遗传学
- 生殖生物学 生殖生物学
- 基因组法规 基因组法规
背景情况:
- 精子生成对男性生育能力至关重要,但可以被遗传和表观遗传因素破坏.
- 虽然编码突变与精子生成受损有关,但非编码突变的作用尚未得到研究.
- 拓相关域 (TAD) 和它们的边界在基因调节中起作用.
研究的目的:
- 为了研究非编码突变对精子生成的影响.
- 评估破坏TAD边界对男性生殖功能的影响.
- 为了比较非编码删除与编码突变对生育能力的影响.
主要方法:
- 在Dmrtb1和Lrp8基因附近确定了一个保存的TAD边界.
- 利用CRISPR-Cas9删除TAD边界的26kb,包括CTCF结合点,在小鼠中.
- 进行了ChIP-seq和Hi-C以确认删除和改变的DNA相互作用.
- 分析了丸基因表达,组织学,半分裂效率,精子生成效率和每日精子生产.
主要成果:
- CRISPR-Cas9删除成功删除了CTCF部位,并增加了跨TAD边界的DNA相互作用.
- 突变小鼠显示丸基因表达变化和组织学异常.
- 观测到的显著降低了半变效率 (47-52%),精子生成效率 (15-18%) 和每日精子生产 (12-28%).
- 尽管精子产量减少,但突变小鼠的生育能力没有显著变化.
结论:
- 破坏TAD边界会通过影响基因调节对精子生产产生负面影响.
- 影响基因调节的非编码突变可能对男性生育能力的影响不如编码突变那么严重.
- 在男性不孕症的病因分析中,应考虑非编码突变.
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