Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany.
Angew Chem Int Ed Engl. 2020 Sep 28;59(40):17378-17382. doi: 10.1002/anie.202009216. Epub 2020 Sep 1.
A new DNA architecture addresses the question, how far energy migrates in DNA and forms cyclobutane pyrimidine dimers (CPDs) as photodamages causing skin cancer. The 3-methoxyxanthone nucleoside allows site-selective photoenergy injection into DNA. The designated CPD site lacks the phosphodiester bond and can be placed in defined distances. The CPD formation links two oligonucleotides together and allows probing by gel electrophoresis. We obtained a sigmoidal distance dependence with R of 25±3 Å. Below R , short-range energy migration occurs with high CPD yields and shallow distance dependence, characteristic for a coherent process. 5-methyl-C as epigenetic modification on the 3'-side facilitates CPD formation. Above R , long-range incoherent energy migration occurs over 30 A-T pairs (105.4 Å). The evidence of long-range CPD formation is fundamental for our understanding of DNA photodamaging. Open access funding enabled and organized by Projekt DEAL.
一种新的 DNA 结构解决了一个问题，即在 DNA 中能量可以迁移多远，并形成环丁烷嘧啶二聚体（CPD）作为导致皮肤癌的光损伤。3-甲氧基黄嘌呤核苷允许对 DNA 进行位点选择性的光能量注入。指定的 CPD 位点缺少磷酸二酯键，可以放置在确定的距离处。CPD 的形成将两个寡核苷酸连接在一起，并允许通过凝胶电泳进行探测。我们得到了一个 R 为 25±3 Å的 S 型距离依赖性。在 R 以下，短程能量迁移发生，具有高 CPD 产率和浅距离依赖性，这是相干过程的特征。在 3'-侧的 5-甲基-C 作为表观遗传修饰，有利于 CPD 的形成。在 R 以上，长程非相干能量迁移跨越 30 个 A-T 对（105.4 Å）发生。长程 CPD 形成的证据对于我们理解 DNA 光损伤是至关重要的。开放获取资金由 Projekt DEAL 提供并组织。
