XPV (xeroderma pigmentosum变种) 基因编码人类DNA聚合酶eta
C Masutani1, R Kusumoto, A Yamada
1Institute for Molecular and Cellular Biology, Osaka University, Suita, Japan.
Nature
|June 29, 1999
概括
Xeroderma pigmentosum变体 (XP-V) 与紫外线损伤后的缺陷DNA复制有关. 研究人员将DNA聚合酶eta确定为可能的原因,纠正了XP-V细胞中的这个缺陷.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 皮肤病学 皮肤病学
背景情况:
- Xeroderma pigmentosum变体 (XP-V) 是一种遗传性疾病,增加了阳光诱导的皮肤癌风险.
- XP-V细胞表现出正常的DNA修复,但在复制紫外线损坏的DNA方面缺乏.
- 怀疑XPV基因在转变损伤DNA合成中的作用,但其产物未被隔离.
研究的目的:
- 为了识别XP-V细胞中转变损伤DNA合成的蛋白质.
- 研究DNA聚合酶eta在UV损伤DNA复制中的作用.
- 为了确定DNA聚合酶eta是否是XPV基因产物.
主要方法:
- 利用一种改进的无细胞测试来进行转变损伤DNA合成.
- 从HeLa细胞中分离出一种DNA聚合酶,能够绕过XP-V提取物中的丁胺二次体.
- 在XP-V细胞中测序了DNA聚合酶eta基因,并测试了重组蛋白功能.
主要成果:
- 他们分离出了一种DNA聚合酶,通过绕过胺二元体来复制紫外线损坏的DNA.
- 这种聚合酶被确定为人类DNA聚合酶eta,是酵母Rad30的同类.
- 所有测试的XP-V细胞都含有DNA聚合酶eta基因的突变.
- 重组人类DNA聚合酶Eta在XP-V细胞提取物中恢复了DNA复制.
结论:
- DNA聚合酶eta很可能是XPV基因产物.
- 在DNA聚合酶eta中的缺陷导致了XP-V的复制缺陷.
- 这一发现澄清了 Xeroderma pigmentosum 变种的分子基础.
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