c-Jun N-终端酸化阻碍了Mbd3/NuRD抑制器复合物的招募
Cristina Aguilera1, Kentaro Nakagawa, Rocio Sancho
1Mammalian Genetics Laboratory, Cancer Research UK London Research Institute, Lincoln's Inn Fields Laboratories, 44 Lincoln's Inn Fields, London WC2A 3PX, UK.
Nature
|January 4, 2011
概括
激活蛋白1 (AP-1) 的转录受c-Jun的调节. 不酸化的c-Jun通过Mbd3招募NuRD抑制复合体,抑制目标基因表达. 基因酸化缓解了这种抑制,促进了基因转录.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
背景情况:
- 被c-Jun等转录因子调节的激活蛋白1 (AP-1) 活性对于肠道细胞增殖和瘤发生至关重要.
- 氨基末端激酶 (JNKs) 酸化c-,增强AP-1的转录活性,但潜在的分子机制尚不清楚.
研究的目的:
- 阐明了c-Jun的N端酸化调节AP-1基因转录的分子机制.
- 调查Mbd3和NuRD抑制组合在肠道环境中的c-Jun介导基因调节中的作用.
主要方法:
- 同免疫沉试验用于评估c-Jun,Mbd3和NuRD组件之间的蛋白质相互作用.
- 染色体免疫沉降测序 (ChIP-seq) 用于识别AP-1向基因并评估基因组修饰.
- 在小鼠 (Mbd3和c-Jun) 中进行条件基因删除,以研究体内功能.
- 对结肠癌细胞系和大肠炎诱导瘤发生的小鼠模型的分析.
主要成果:
- 非化c-Jun,但不是N-终端化c-Jun,与Mbd3相互作用,以招募NuRD抑制器复合体.
- 结肠癌细胞中Mbd3的枯竭导致了AP-1向基因的激素乙化和表达的增加,包括干细胞标记物lgr5.5.
- 在小鼠中,肠特异的Mbd3缺失增强了c-Jun活性,促进了前代细胞的增殖,并增加了对大肠炎诱导的肠瘤发生的易感性.
- 在Mbd3缺乏的小鼠中,一个c-Jun等位基因的失活会逆转超增殖并减少瘤发生.
结论:
- c-Jun的交换活化域招募Mbd3/NuRD来抑制AP-1的基因表达.
- 通过JNK介导的c-Jun的N端酸化缓解了Mbd3/NuRD介导的抑制,从而增加了基因转录.
- 这种涉及c-Jun,Mbd3和NuRD的调节轴在控制肠道原始细胞的增殖和瘤发生方面发挥着至关重要的作用,特别是在对炎症的反应中.
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