由藻类TET同类催化的一种维生素C衍生的DNA修饰
Jian-Huang Xue1, Guo-Dong Chen1, Fuhua Hao2
1State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China.
Nature
|May 3, 2019
概括
科学家们在藻类中发现了一种新的DNA修饰,这种修饰由使用维生素C的TET同源酶 (CMD1) 催化.这种表观遗传标记影响了Chlamydomonas reinhardtii的光合作用调节和应激反应.
科学领域:
- 表观遗传学和DNA修饰
- 分子生物学
- 植物科学
背景情况:
- 细胞因子甲基化 (5mC) 是许多生物体的关键表观遗传标记.
- 在哺乳动物中,十一转位 (TET) 氧化酶介导5mC氧化和DNA脱甲基化.
- 其他真核生物中TET同类的功能,特别是DNA基因修饰,在很大程度上是未知的.
研究的目的:
- 在绿藻Chlamydomonas reinhardtii中研究TET同类的酶活性和功能.
- 识别新型DNA修饰及其在真核生物表观遗传调节中的作用.
- 探索DNA修饰,维生素C和光合作用应激反应之间的联系.
主要方法:
- 在Chlamydomonas reinhardtii中发现了一种5mC修饰酶 (CMD1).
- 描述了CMD1的催化活性,需要Fe (II) 和L-酸 (维生素C) 作为辅基.
- 使用基因组分析分析了野生型和CMD1突变菌株中维生素C衍生的DNA修饰的存在.
主要成果:
- CMD1 催化了 5mC 的糖部分的结合,形成了新的 DNA 基基修饰.
- 这种变化依赖于维生素C,并产生酸和二氧化碳的副产品.
- 在强光下,CMD1突变细胞的适应性降低,光保护基因LHCSR3的高甲基化和下调.
结论:
- 通过使用维生素C的分离TET同类物 (CMD1) 催化的一种新型真核DNA基改.
- 这种维生素C衍生的修饰作为潜在的表观遗传标记,可能会抵消DNA甲基化.
- 通过CMD1调节的DNA修饰在Chlamydomonas reinhardtii的光合作用和应激耐受性中起作用.
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