...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Characterization of DNA topoisomerase II alpha/beta heterodimers in HeLa cells
【24h】

Characterization of DNA topoisomerase II alpha/beta heterodimers in HeLa cells

机译：HeLa细胞中DNA拓扑异构酶IIα/β异二聚体的表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In mammalian cells, DNA topoisomerase II is the product of two distinct genes encoding the alpha and beta isoforms of the enzyme. Besides homodimeric topoisomerase II alpha and II beta, we have recently shown that alpha/beta heterodimers constitute a third population of topoisomerase II in HeLa cells. We found that topoisomerase II heterodimers are not restricted to HeLa cells but exist in different mammalian cell types, and up to 25% of the total topoisomerase II beta population is involved in heterodimer formation. Studies of topoisomerase II phosphorylation in HeLa cells show that heterodimers are phosphorylated in vivo to a significantly lower level compared to homodimeric alpha enzymes, but in contrast to the latter neither heterodimers nor topoisomerase II beta homodimers coprecipitate together with a kinase activity that is able to mediate their phosphorylation. However, both enzymes can still be phosphorylated by exogenously added casein kinase II. The differential phosphorylation of topoisomerase II heterodimers suggests an alternative regulation of this topoisomerase II subclass compared to the homodimeric topoisomerase II alpha counterparts. [References: 46]
机译：在哺乳动物细胞中，DNA拓扑异构酶II是编码该酶的α和β同工型的两个不同基因的产物。除了同型二聚体拓扑异构酶IIα和II beta，我们最近还发现，α/β异二聚体构成HeLa细胞中拓扑异构酶II的第三种群。我们发现拓扑异构酶II异二聚体不限于HeLa细胞，而是存在于不同的哺乳动物细胞类型中，并且高达25％的拓扑异构酶II beta总体人口参与异二聚体的形成。 HeLa细胞中拓扑异构酶II磷酸化的研究表明，与同型二聚体α酶相比，异二聚体在体内的磷酸化水平显着降低，但与后者相反，异二聚体和拓扑异构酶IIβ同型二聚体均不会与能够介导的激酶活性一起共沉淀他们的磷酸化。但是，两种酶仍然可以被外源添加的酪蛋白激酶II磷酸化。拓扑异构酶II异二聚体的差异磷酸化表明，与同型二聚拓扑异构酶IIα对应物相比，该拓扑异构酶II亚类具有另一种调节方式。 [参考：46]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号