PHF2通过凝聚蛋白调节神经干细胞中的基因组拓和DNA复制
Jia Feng1, You Heng Chuah1,2, Yajing Liang1
1Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore.
Nucleic acids research
|May 29, 2024
概括
基因组脱甲基酶PHF2与凝聚素合作,调节神经干细胞中的DNA复制. 失去PHF2会激活休眠的起源,通过削弱拓相关域 (TADs) 来破坏复制.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- 拓相关域 (TADs) 组织基因组,影响基因表达和DNA复制时间.
- 表观遗传调节剂通过凝聚素影响TADs以调节DNA复制的作用尚不清楚.
- 凝聚素是一种蛋白质复合体,对TAD组织和基因组稳定性至关重要.
研究的目的:
- 为了研究基因组脱甲酶PHF2在小鼠神经干细胞 (NSCs) 内DNA复制调节中的作用.
- 确定PHF2是否与凝聚素子单元相互作用,并影响TAD和复制起源.
- 阐明PHF2影响DNA复制和NSC增殖的机制.
主要方法:
- 同免疫沉用于识别PHF2和凝聚素子单元 (RAD21) 之间的蛋白相互作用.
- 对PHF2淘汰赛 (KO) 鼠神经干细胞中的DNA复制,复制起源激活和增殖的分析.
- 染色体免疫沉测序 (ChIP-seq) 用于绘制PHF2/RAD21共结区域,CTCF占用率和TAD边界的地图.
- 评估PHF2的基因表达和基因素脱甲基酶活性.
主要成果:
- 在小鼠NSC中,PHF2直接与RAD21,一个核心凝聚素子单元联系在一起.
- 通过激活休眠的复制原点和削弱TAD和染色质环,PHF2损失会损害DNA复制.
- 对于CTCF来说,PHF2/RAD21共同结合的区域是丰富的,并且表现出活跃复制起源的特征,作为域边界.
- 对于PHF2在DNA复制或NSC增殖中的作用,不需要PHF2的基因组脱甲基酶活性.
结论:
- PHF2作为凝聚素的拓配件,促进其定位到TAD和染色质环.
- PHF2-凝聚蛋白复合体抑制休眠的复制起源,确保NSC中高效的DNA复制.
- PHF2 调节DNA复制独立于其酶激素脱甲基酶活性,突出显示了一种新的非表观遗传作用.
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