UV light-damaged DNA and its interaction with human replication protein A: an atomic force microscopy study
UV light-damaged DNA and its interaction with human replication protein A: an atomic force microscopy study
复制标题
DOI：
10.1093/nar/gkf378
复制
发表时间：
2002-06-15
影响因子：
14.9
通讯作者：
Krausch, G
中科院分区：
文献类型：
--
作者：
Lysetska, M;Knoll, A;Krausch, G
我们利用原子力显微镜（AFM）对未损伤和紫外线损伤的DNA片段及其与人类复制蛋白a （RPA）的复合物进行了成像。为了成像，分子在接近生理条件下固定在云母表面。紫外线照射前后538 bp DNA的定量测定显示，紫外线照射减少了轮廓和持续长度以及端到端均方距离。紫外线损伤DNA与RPA的复合物是核苷酸切除修复初始步骤的重要组成部分，可以用AFM高分辨率检测到，并揭示与复合物形成相关的DNA构象变化。通过相像分析，我们能够在复合物中区分蛋白质和DNA。DNA分子被发现“包裹”在RPA周围，这反过来又导致其明显的轮廓长度大大减少。
We have imaged a non-damaged and UV-damaged DNA fragment and Its complexes with human replication protein A (RPA) using tapping mode atomic force microscopy (AFM). For Imaging, molecules were Immobilized under nearly physiological conditions on mica surfaces. Quantitative sizing of the 538 bp DNA before and after UV light treatment shows a reduction In the contour and persistence lengths and mean square end-to-end distance as a consequence of UV irradiation. Complexes of the UV-damaged DNA with RPA, an essential component of the initial steps of nucleotide excision repair, can be detected at high resolution with AFM and reveal conformational changes of the DNA related to complex formation. By phase image analysis we are able to discriminate between protein and DNA In the complexes. The DNA molecules are found to 'wrap' around the RPA, which In turn results In a considerable reduction in its apparent contour length.