不典型的CTCF结合模式促进了组织特异性和神经活动依赖的基因表达状态
Morgan Crewe1,2,3, Amir Segev1,2,3, Richard Rueda1,2,3
1Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Molecular neurobiology
|November 18, 2023
概括
大多数CTCF结合位点 (CBS) 偏离了共识的DNA序列,不同的结合模式影响了发育过程中的基因活性和对刺激的反应. 这揭示了CTCF的新型监管角色.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- CCCTC结合因子 (CTCF) 是一个关键的转录调节器,它结合DNA以影响基因组结构和基因表达.
- CTCF通常识别特定的20bpDNA共识序列,但其结合位点的全谱仍然不完全理解.
研究的目的:
- 研究基因组中CTCF结合位点 (CBS) 的多样性,特别关注异型位点.
- 了解CBS变异如何影响神经发育过程中的基因调节以及对刺激的反应.
主要方法:
- 在培养的皮层神经元中对CTCF占用量的全基因组评估.
- 对已识别的CBS的DNA序列变异的分析.
- 与基因活动标记物 (例如,H3K27ac) 和基因组结构 (TAD,循环) 的CBS相关性.
主要成果:
- 大约22%的CBS缺乏正规的CTCF动机,序列退化影响CTCF指6和7.
- 非典型的CBS的第二种模式,与共识动机无关,在组织特异性基因中发现,并与增强剂 (H3K27ac) 相关.
- 动态CBS变化发生在神经分化和刺激过程中,通过循环依赖和独立的机制影响基因活性.
结论:
- 非典型的CTCF结合部位很普遍,在调节基因活性方面起着至关重要的作用.
- CTCF的多种结合模式允许在发育过程中和响应环境线索时进行动态基因调节.
- 这些发现扩大了我们对CTCF在基因组组织和基因表达中的作用的理解.
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