继承H3K9甲基化调节Drosophila早期胚胎中的基因组结构
Nazerke Atinbayeva1,2, Iris Valent3, Fides Zenk4
1Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg im Breisgau, Germany.
The EMBO journal
|June 3, 2024
概括
像H3K9me3这样的母性遗传的质子修饰对于在早期果胚胎中组织构成性异染色素至关重要. 这种表观遗传标记驱动HP1a聚类,对基因组完整性和发育至关重要.
科学领域:
- 表观遗传学和发育生物学
- 染色体结构和功能 染色体结构和功能
背景情况:
- 构成性异种染色素确保了基因组稳定性和转录沉默.
- 在胚胎早期发育过程中构成性异染色素的建立和功能仍然不太清楚.
- 基因组H3氨酸9三甲基化 (H3K9me3) 和异色素蛋白1a (HP1a) 是构成性异色素的关键标记物.
研究的目的:
- 调查母性遗传H3K9me3在果早期发育过程中构成性异染色素的建立中的作用.
- 确定H3K9me3在HP1a招募和胚胎中的异染色体组织中的精确功能.
主要方法:
- 对H3K9me3.3的母亲遗传分析
- 定量CUT&Tag测定测量HP1a结合的方法.
- 4D显微镜观察HP1a动态和异色素蛋白结构.
- 生物物理建模分析HP1a聚类和压缩.
主要成果:
- H3K9me3是从母亲的生殖系传播的,对于构成性的异染色体组织至关重要.
- 缺乏H3K9甲基化的胚胎表现出周心体脱凝,线粒缺陷和致命性.
- H3K9me2/3对于HP1a的招募是不可或缺的,但对于HP1a的聚类和异色染色体紧缩至关重要.
- 单独的HP1a结合,没有H3K9me2/3,是不够的适当的胚胎发育.
结论:
- 在果胚胎中,母体沉积的H3K9me3和相关的希斯甲基转移酶对于初始异染色素的形成至关重要.
- H3K9me2/3的主要作用是促进HP1a的聚类,驱动异染色质缩而不是直接招募.
- 破坏H3K9甲基化严重影响基因组组织,并导致胚胎死亡,突出其在早期发育中的基本作用.
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