在Drosophila中远距离的Hox loci之间,多胞体依赖的调节接触
Frédéric Bantignies1, Virginie Roure, Itys Comet
1Institut de Génétique Humaine, CNRS UPR 1142, Montpellier, France. frederic.bantignies@igh.cnrs.fr
Cell
|January 19, 2011
概括
果中的Hox基因在Polycomb体内物理相互作用,这一过程对于保持基因沉默至关重要. 这种3D核组织稳定了表观遗传记忆,影响了发育.
科学领域:
- 发育生物学 发展生物学
- 遗传学 是一个遗传学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 在Drosophila melanogaster中,Hox基因被组织成前部 (Antennapedia复合体) 和后部 (bithorax复合体) 集群.
- 这两种霍克斯基因集群都是由多组 (PcG) 蛋白质表观遗传抑制的.
研究的目的:
- 研究核中的霍克斯基因集群的空间组织和相互作用.
- 确定PcG蛋白在调解这些相互作用中的作用及其对基因沉默的影响.
主要方法:
- 利用显微镜技术观察Drosophila组织中的PcG体内的Hox基因同位化.
- 研究了这些相互作用的发育性和PCG依赖性.
- 检查了涉及其他PCG标基因的基因相互作用网络.
- 分析了突变对霍克斯基因沉默和同源现象型的影响.
主要成果:
- 两个霍克斯复合体的基因在核心压缩期间在核PcG体内同位.
- 这种局部化在发育过程中加剧,并且依赖于PcG蛋白.
- 霍克斯基因接触在物种之间得到保护,并集成到更广泛的PCG基因网络中.
- 在一个霍克斯位点的突变妥协,使另一个沉默,加剧了同源的表型.
结论:
- 核中的Polycomb目标基因的三维组织对于稳定的表观遗传基因沉默至关重要.
- 由PcG蛋白调解的核架构在维持发育基因表达模式方面发挥着关键作用.
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