抑制和3D重组解决了进化重新排列基因组中的监管冲突
Alessa R Ringel1, Quentin Szabo2, Andrea M Chiariello3
1Max Planck Institute for Molecular Genetics, Berlin, Germany; Institute for Medical and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany; Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.
Cell
|September 30, 2022
概括
新基因可以融入现有的调节区域,而不会破坏它们. 在特定的背景下,DNA甲基化防止干扰,允许独立的基因表达和进化灵活性.
科学领域:
- 基因组学
- 发育生物学
- 进化生物学
背景情况:
- 调控环境对于基因表达在发育过程中至关重要.
- 在新基因的结合过程中保持调节完整性是不太了解的.
- 拓相关域 (TAD) 组织基因组并影响基因调节.
研究的目的:
- 研究一种哺乳动物特异性基因 (Zfp42) 如何融入古老的TAD而不会影响现有的基因 (Fat1) 的表达.
- 阐明在进化过程中在共享的TAD中保持独立基因调节的机制.
- 确定TAD内部的调节复杂性是否是一种常见的进化现象.
主要方法:
- 在胚胎干细胞 (ESC) 和胚胎肢体中研究了Zfp42和Fat1的基因表达和调控机制.
- 分析了色素活性,CTCF/凝聚素结合,增强剂活性和DNA甲基化模式.
- 检查了TAD分区和核封面的附着.
- 在TAD中进行基因分布的全基因组分析.
主要成果:
- 通过TAD分区在ESC中物理分离Zfp42和Fat1,不同的增强剂驱动独立表达.
- 染色体活动,而不是CTCF/凝聚素,驱动ESC的这种分离.
- 在胚胎肢体中,Zfp42在Fat1的TAD中不活跃,对Fat1增强剂没有反应.
- 而不是增强剂不兼容性或核附着性, 解释了Zfp42的无反应性.
- 大多数TAD全基因组包含多个独立表达的基因.
结论:
- 多种机制,包括染色体活性和上下文依赖的DNA甲基化,促进独立调节的基因在现有的基因位点内集成.
- 在TAD中的调节复杂性是脊椎动物进化的共同特征.
- 这项研究提供了基因组如何适应新基因,同时保持调控完整性的见解.
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