通过CXXC域蛋白 IDAXC调节TET2表达和5-甲基细胞因氧化
Myunggon Ko1, Jungeun An, Hozefa S Bandukwala
1Division of Signaling and Gene Expression, La Jolla Institute for Allergy & Immunology, La Jolla, California 92037, USA.
Nature
|April 9, 2013
概括
蛋白质IDAX (CXXC4) 通过与DNA结合并导致TET2降解来调节TET2的表达,从而影响DNA甲基化擦除. 这项研究揭示了IDAX作为TET2和TET3活动的新型调节剂.
科学领域:
- 表观遗传学和基因调控
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 十一转位 (TET) 蛋白质是活性DNA脱甲基化过程中至关重要的二氧化酶.
- 一种Wnt信号传递抑制剂的IDAX (CXXC4) 与癌症有关.
- 伊达克斯从一个祖先的TET2基因进化,将其CXXC域与催化域分开.
研究的目的:
- 研究IDAX对TET2蛋白表达和活性的调控作用.
- 阐明IDAX影响TET2水平的机制.
- 探索对TET蛋白调节和DNA甲基化动态的更广泛影响.
主要方法:
- 对IDAX与TET2的催化域相互作用的分析.
- 使用其CXXC域评估IDAX的DNA结合特性.
- 在细胞模型中对IDAX表达 (枯竭和shRNA) 的实验操纵.
- 在不同的IDAX条件下研究酶激活和TET蛋白水平.
主要成果:
- IDAX与非甲基化CpGDNA序列结合,并与TET2催化域相互作用.
- IDAX表达导致酶激活和TET2蛋白降低调节,这取决于IDAX的DNA结合CXXC域.
- 减少IDAX可以防止TET2在分化小鼠胚胎干细胞中的下调,而减少IDAX可以增加U937细胞中的TET2表达.
- 通过其CXXC域,TET3的表达和活动也受到调节.
结论:
- 伊达克斯作为TET2的新型调节剂,通过依赖DNA结合的机制调解其降解.
- IDAX的单独的CXXC域和TET3的链接的CXXC域被确定为酶激活和TET酶活性的关键调节者.
- 这些发现为复杂的DNA甲基化调节及其在疾病中的潜在作用提供了新的见解.
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