在全中心丝甲虫中,染色体具有独特的区域和隔间组织
J Gil1, E Navarrete2,3, L F Rosin4
1Institut Curie, PSL University, Sorbonne Université, CNRS, Nuclear Dynamics, 75005 Paris, France.
Research square
|August 16, 2024
概括
丝甲的3D基因组架构具有高度分离的染色体区域 (CTs) 和一个新的孤立的"S"隔间. 这揭示了独特的循环挤出机制,驱动了昆虫基因组组织和进化可塑性.
科学领域:
- 基因组学和分子生物学
- 染色体生物学 染色体生物学
- 细胞基因组组织组织
背景情况:
- 多细胞真核生物表现出染色体区域 (CTs),染色体区 (A/B) 和像TADs这样的绝缘域.
- 大多数研究都集中在有限的模型生物体上,使得像昆虫这样的大群体在3D基因组架构方面未得到充分探索.
研究的目的:
- 通过使用综合实验和建模方法,研究丝虫Bombyx mori的3D基因组架构.
- 了解昆虫染色体组织的原理及其进化含义.
主要方法:
- 雇佣了Hi-C进行全基因组的联系人映射.
- 利用生物物理建模来模拟和理解域形成.
- 应用显微镜用于可视化3D基因组结构.
主要成果:
- 在 *B. mori* 中观察到高度分离的染色体区域 (CTs),与其他真核生物不同.
- 确定了活跃的 (A) 和不活跃的 (B) 分区,A-A接触驱动分区.
- 发现了一种独特的自我接触和外围定位的新型隐蔽的"S",表现出发育可塑性.
- 生物物理建模和Hi-C数据支持局部循环挤出对于S形成至关重要,具有非均的挤出器分布.
结论:
- 丝鼠表现出独特的3D基因组组织,包括一个新的隔离.
- 循环挤出在昆虫中得到支持,挤出机具有独特的不均分布.
- 这些发现突出了3D基因组组织的进化可塑性,由已知的过程的新组合驱动.
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