由1,4-二氧玻丁基底性损伤造成的DNA跨链交叉链的形成
1Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society
|October 8, 2009
概括
氧化基底病变5'-(2--1,4-二氧化) (DOB) 与DNA形成可逆跨链交叉链 (ICLs). 这种复杂的病变与单链断裂相邻,在修复过程中可以导致双链断裂.
科学领域:
- 分子生物学分子生物学
- DNA损伤和修复的过程
- 化学生物学 化学生物学
背景情况:
- 氧化基底性病变,如5'-(2-酸-1,4-二氧化) (DOB),是由DNA损伤剂引起的.
- 这些病变可以与单链断裂一起发生,从而造成复杂的DNA损伤.
研究的目的:
- 为了研究DNA中DOB病变的形成和特性.
- 了解 DOB 损伤产生的链间交叉链 (ICL) 的形成机制和选择性.
主要方法:
- 在DNA中独立生成DOB病变.
- 使用单化模型进行产品研究.
- 机械学研究和分子建模.
主要成果:
- DOB 损伤可逆地与3'-相邻核酸相反的腺素 (dA) 选择性地形成跨链交叉链 (ICL).
- ICL的形成涉及DOB损伤的二甲基和DA的外循环胺之间的凝结.
- DNA序列和局部结构决定了dA反应的选择性,不同于自由扩散的分子.
结论:
- DOB病变与dA形成选择性ICL的能力受到其局部DNA环境和邻近的影响.
- 与单链断裂相邻的DOB病变形成集群病变,由于它们在核酸切割修复过程中可能诱导双链断裂,因此具有重要意义.
相关概念视频
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01:54Base Excision Repair
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01:54Base Excision Repair
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The first step of...
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TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
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