由三种Drosophila甲基转移酶对基因组上下文依赖的基因素H3K36甲基化以及对专用染色体读取器的含义
Muhunden Jayakrishnan1, Magdalena Havlová2, Václav Veverka2,3
1Molecular Biology Division, Biomedical Center, Ludwig-Maximilians-Universität, 82152 Munich, Germany.
Nucleic acids research
|March 31, 2025
概括
基因组H3 lysine 36 (H3K36) 甲基化,包括H3K36me1,H3K36me2和H3K36me3,定义了不同的染色质状态. 表观遗传阅读器MSL3和JASPer结合了H3K36me2和H3K36me3,扩大了它们的基因组范围.
科学领域:
- 表观遗传学和染色体生物学
- 分子生物学分子生物学
- 德洛索菲拉黑虫 模型系统模型
背景情况:
- 基因组H3 lysine 36三甲基化 (H3K36me3) 是活性染色体的标志,由表观遗传阅读器解释转录和染色体完整性.
- 在Drosophila中,MSL3结合H3K36me3进行剂量补偿,而JASPer则将JIL1激酶招募到活性色素中.
- 之前的研究表明,H3K36me3耗尽对读者互动的局部特异性影响,需要进行系统的调查.
研究的目的:
- 系统地研究不同H3K36甲基化状态 (H3K36me1,H3K36me2,H3K36me3) 在定义色素状态中的作用.
- 绘制由特定的H3K36甲基转移酶 (Set2,NSD,Ash1) 控制的基因组区域的地图.
- 为了确定表观遗传阅读器MSL3和JASPer在不同H3K36甲基化状态中的结合特异性.
主要方法:
- 在定义的Drosophila细胞模型中对H3K36甲基化的系统研究.
- 在甲基转移酶Set2,NSD和Ash1.1耗尽后监测H3K36甲基化变化.
- 绘制MSL3和JASPer绑定和直接亲和度测量对读者-希斯相互作用的映射.
主要成果:
- 每个H3K36me1,H3K36me2和H3K36me3都导致了不同的染色质状态,挑战了当前的模型.
- Set2,NSD和Ash1甲基转移酶控制H3K36在专用基因组区域的甲基化,重叠最小.
- MSL3和JASPer结合H3K36me2和H3K36me3,扩大它们的目标部位并提高它们的功能稳定性.
结论:
- H3K36甲基化场景比以前认为的要复杂得多,单基,二基和三基甲基化有不同的作用.
- 特定的甲基转移酶在定义的基因组环境中建立独特的甲基化特征,包括euchromatin,heterochromatin和增强剂.
- MSL3和JASPer对H3K36me2和H3K36me3的双重特异性增加了表观遗传调节的效率和范围.
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