A spin-labeled abasic DNA substrate for AP endonuclease.
A spin-labeled abasic DNA substrate for AP endonuclease.
复制标题
AP 核酸内切酶的自旋标记脱碱基 DNA 底物。
DOI：
10.1006/bbrc.2001.5827
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Strauss,PR
中科院分区：
文献类型：
--
作者：
Kolaczkowski,SV;Perry,A;Mckenzie,A;Johnson,F;Budil,DE;Strauss,PR
我们报告的自旋标记的ds 23-mer寡核苷酸的高场电子自旋共振（ESR）的第一次观察，并证明它与AP核酸内切酶，在DNA脱碱基位点修复的关键酶相互作用。通过尿嘧啶DNA糖基化酶处理在上链的位置12处具有U的自旋标记的23-mer以提供脱碱基底物。在离脱碱基位点两个核苷酸的地方有一个自旋标记，当标记在脱碱基位点的3′端而不是5′端时，AP内切结合并切割。这些结果证实，直接上游的脱碱基位点的处置是特别关键的AP内切酶裂解，并建立在这个重要的酶的DNA-蛋白质相互作用，可以使用自旋标记的基板进行检查。
We report the first observation of a spin-labeled ds 23-mer oligonucleotide by high-field electron spin resonance (ESR) and demonstrate that it interacts with AP endonuclease, the key enzyme in DNA abasic site repair. The spin labeled 23-mer with a U at position 12 of the upper strand is processed by uracil DNA glycosylase to provide the abasic substrate. With a spin-label two nucleotides away from the abasic site, AP endo binds and cleaves when the label is 3′ but not 5′ to the abasic site. These results confirm that the disposition of the bases immediately upstream of the abasic site is particularly critical for cleavage by AP endo, and establish that DNA–protein interactions in this important enzyme can be examined using spin-labeled substrates.