Genome-Wide Mapping of Oxidative DNA Damage via Engineering of 8‑Oxoguanine DNA Glycosylase

The occurrence of 8-oxo-7,8-dihydroguanine (OG) in the genome, as one of the major DNA oxidative damages, has been implicated in an array of biological processes, ranging from mutagenesis to transcriptional regulation. Genome-wide mapping of oxidative damages could shed light on the underlying cellular mechanism. In the present study, we engineered the hOGG1 enzyme, a primary 8-oxoguanine DNA glycosylase, into a guanine oxidation-profiling tool. Our method, called enTRAP-seq, successfully identified more than 1400 guanine oxidation sites in the mouse embryonic fibroblast genome. These OG peaks were enriched in open chromatin regions and regulatory elements, including promoters, 5′ untranslated regions, and CpG islands. Collectively, we present a simple and generalizable approach for the genome-wide profiling of DNA damages with high sensitivity and specificity.基因组中8-氧代-7,8-二氢鸟嘌呤（8-oxo-7,8-dihydroguanine，简称OG）作为主要的DNA氧化损伤之一，已被证实与从诱变到转录调控的一系列生物学过程密切相关。对氧化损伤开展全基因组定位研究，有助于揭示其潜在的细胞机制。本研究中，我们将核心的8-氧鸟嘌呤DNA糖苷酶（8-oxoguanine DNA glycosylase）hOGG1工程改造为鸟嘌呤氧化谱分析工具。我们将该方法命名为enTRAP-seq，其成功在小鼠胚胎成纤维细胞基因组中鉴定出超过1400个鸟嘌呤氧化位点。这些OG峰在开放染色质区域及调控元件（包括启动子、5'非翻译区与CpG岛）中显著富集。综上，我们提出了一种简便且可推广的方法，可实现高灵敏度、高特异性的全基因组DNA损伤谱分析。