酵母DNA结合酶IV介导非同源DNA末端的连接
T E Wilson1, U Grawunder, M R Lieber
1Washington University School of Medicine, Division of Laboratory Medicine, Department of Pathology, St Louis, Missouri 63110, USA.
Nature
|July 31, 1997
概括
酵母DNA结合酶IV (DNL4) 对于非同类末端结合 (NHEJ) 是一种DNA修复途径至关重要. 细菌有两个不同的DNA结合路径,一个涉及DNL4,另一个涉及CDC9.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 酵母菌Saccharomyces cerevisiae具有人类Ku DNA结尾结合蛋白 (HDF1和KU80) 的同类,这表明它具有非同类双链结尾结合 (NHEJ) 的能力.
- 了解酵母中介于NHEJ的DNA连接酶是解读哺乳动物DNA连接酶在DNA双链断裂修复 (DSBR) 和V(D) J重组中的作用的关键.
研究的目的:
- 为了识别导致S. cerevisiae中NHEJ的DNA连接酶.
- 为了研究酵母中DNA连接酶和DNA修复途径之间的功能关系.
主要方法:
- 对S. cerevisiae突变的遗传分析,包括dnil4和hdf1.
- 补充研究涉及DNL4和CDC9的过度表达.
- 在各种辐射条件下对突变菌株的表型分析.
主要成果:
- S. cerevisiae 具有两种 DNA 连接酶: CDC9 (DNA 连接酶 I 的同源) 和 DNL4 (一种新的 DNA 连接酶 IV 的同源).
- dnl4突变体在精确和最终处理的NHEJ中表现出缺陷,DNL4和HDF1显示出表性关系.
- DNL4缺乏不会影响细胞生长或对CDC9介导的电离和紫外线辐射的反应,这表明有单独的结合路径.
结论:
- S. cerevisiae利用两个不同的独立的DNA结合路径.
- DNL4是参与S. cerevisiae中NHEJ的主要DNA结合酶,与CDC9-介导通路独立运作.
相关概念视频
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The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...


