细胞蛋白甲基化和DNA序列背景对紫外线诱导的CPD形成的全基因组影响
Hannah E Wilson1, John J Wyrick1
1School of Molecular Biosciences, Washington State University, Pullman, Washington, USA.
Environmental and molecular mutagenesis
|August 9, 2023
概括
细胞因子甲基化显著增加了近两倍的紫外线B (UVB) DNA损伤,特别是循环丁胺二聚体 (CPD). 这种效应依赖于序列,在特定情况下,甲基化细胞因子显示出CPD形成的最大增加.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 紫外线 (UV) 光暴露是由于DNA损伤导致皮肤癌的主要原因.
- 循环butan胺二聚体 (CPD) 是UV诱导的DNA损伤的最常见形式.
- 在DNA中的甲基化细胞因子,特别是在CG二核酸中,涉及到皮肤癌突变热点,但它们在CPD形成中的作用仍在争论中.
研究的目的:
- 为了研究细胞因子甲基化对紫外线诱导的环丁胺二聚体 (CPD) 在基因组中的形成的影响.
- 为了确定细胞因子甲基化是否对UVB和UVC辐射有不同的影响CPD形成.
- 为了澄清与此前有关甲基化对UVDNA损伤的影响的相互矛盾的发现.
主要方法:
- 利用CPD-seq,一种全基因组技术,绘制CPD的地图.
- 在体外使用CpG甲基转移酶 (M.SssI) 实验性甲基化酵母DNA.
- 在暴露于UVB和UVC辐射后,在甲基化与非甲基化DNA中比较CPD形成.
主要成果:
- 与未甲基化DNA相比,细胞酸甲基化几乎使UVB诱导的CPD形成翻了一番.
- 甲基化诱导的CPD形成的程度取决于DNA序列的背景.
- 具有5'关氨基基的序列背景 (例如,GCCG,GTCG) 显示了UVB诱导的CPD的最显著增加.
- 氨酸甲基化也调节了UVC诱导的CPD形成,尽管比UVB少得多.
结论:
- 细胞因子甲基化增强UVB诱导的CPD形成,特别是在特定的DNA序列环境中.
- 这些发现有助于协调以前关于甲基化和紫外线损伤的研究中的相互矛盾的数据.
- 这项研究定义了细胞因子甲基化对紫外线诱导的DNA损伤在真核生物基因组中的影响.
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