Promyelocytic leukemia protein PML inhibits Nur77-mediated transcription through specific functional interactions.
Promyelocytic leukemia protein PML inhibits Nur77-mediated transcription through specific functional interactions.
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早幼粒细胞白血病蛋白 PML 通过特定的功能相互作用抑制 Nur77 介导的转录。
DOI：
10.1038/sj.onc.1205491
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发表时间：
2002
期刊：
影响因子：
8
通讯作者：
Chang,Kun-Sang
中科院分区：
文献类型：
--
作者：
Wu,Wen-Shu;Xu,Zhi-Xiang;Ran,Ruixiang;Meng,Feng;Chang,Kun-Sang
早幼粒细胞白血病蛋白 PML 是一种肿瘤和生长抑制剂，在细胞凋亡和细胞周期进程调节的多种途径中发挥重要作用。我们之前的研究和其他研究也证明了 PML 通过与转录共激活因子 CBP 和转录辅抑制因子 HDAC 的关联在转录调控中的作用。在这里，我们证明 PML 是 Nur77 的有效转录抑制因子，Nur77 是一种孤儿受体，也是类固醇受体蛋白超家族的成员。我们发现 PML 通过两种蛋白质之间的物理和功能相互作用抑制 Nur77 介导的反式激活。 PML 在体外通过 GST-pull down 测定和体内通过共免疫沉淀测定与 Nur-77 相互作用。 PML/Nur77 在双重免疫荧光染色和共聚焦显微镜分析中在体内共定位。我们的研究进一步表明，PML 的卷曲螺旋结构域与 Nur77 的 DNA 结合结构域（氨基酸 267-332）相互作用。电泳迁移率变动分析表明，PML 以剂量依赖性方式干扰 Nur77 DNA 结合。这项研究表明，PML 与 Nur77 的 DNA 结合域相互作用，并通过阻止其与目标启动子结合来抑制转录。这项研究支持 PML/Nur77 相互作用在调节细胞生长和凋亡中的作用。
The promyelocytic leukemia protein PML is a tumor and growth suppressor and plays an important role in a multiple pathways of apoptosis and regulation of cell cycle progression. Our previous studies and others also documented a role of PML in transcriptional regulation through its association with transcription coactivator CBP and transcription corepressor HDAC. Here, we showed that PML is a potent transcriptional repressor of Nur77, an orphan receptor and a member of the steroid receptor superfamily of proteins. We found that PML represses Nur77-mediated transactivation through a physical and functional interaction between the two proteins. PML interacts with Nur-77 in vitro in a GST-pull down assay and in vivo by coimmunoprecipitation assay. PML/Nur77 colocalized in vivo in a double immunofluorescent staining and confocal microscopic analysis. Our study further showed that the coiled–coil domain of PML interacts with the DNA-binding domain of Nur77 (amino acids 267–332). Electrophoretic mobility shift assay demonstrated that PML interferes with Nur77 DNA binding in a dose-dependent manner. This study indicates that PML interacts with the DNA-binding domain of Nur77 and represses transcription by preventing it from binding to the target promoter. This study supports a role of PML/Nur77 interaction in regulating cell growth and apoptosis.