Inhibition of CBF/NF-Y mediated transcription activation arrests cells at G2/M phase and suppresses expression of genes activated at G2/M phase of the cell cycle.
Inhibition of CBF/NF-Y mediated transcription activation arrests cells at G2/M phase and suppresses expression of genes activated at G2/M phase of the cell cycle.
复制标题
DOI：
10.1093/nar/gkl801
复制
发表时间：
2006
影响因子：
14.9
通讯作者：
中科院分区：
文献类型：
--
作者：
以往的研究表明，CBF/NF-Y(CBF/NF-Y)转录因子与细胞启动子结合是细胞增殖所必需的。这一观察结果促使我们研究CBF在细胞周期进程和细胞周期调控转录中的功能。在这项研究中，我们使用四环素可诱导的腺病毒载体来表达截短的CBF-B亚单位BDBD，它在各种哺乳动物细胞系中缺乏转录激活结构域。BDBD多肽与细胞CBF-A/CBF-C相互作用，并与含有CBF结合位点的启动子结合。有趣的是，BDBD在多种哺乳动物细胞中的表达导致细胞增殖抑制和特异性细胞周期停滞于G2/M期。基因表达分析表明，BDBD的表达强烈抑制细胞周期相关基因Cyclin B1、Aurora A和CDK1的转录激活，这些基因是G2/M期细胞周期进程的关键调节因子。染色质免疫沉淀分析表明，BDBD显著抑制TATA结合蛋白TBP与Cyclin B1和Aurora A启动子的结合，但不抑制E2F3激活剂与Cyclin B1启动子的结合。本研究提示，CBF-B的激活结构域在G2/M期Cyclin B1和Aurora A基因的转录激活中起重要作用，从而调节G2/M期细胞周期进程。
Previous studies showed that binding of the CBF/NF-Y (CBF) transcription factor to cellular promoters is essential for cell proliferation. This observation prompted us to investigate the function of CBF in relation to cell cycle progression and in cell-cycle-regulated transcription. In this study, we used a tetracycline-inducible adenoviral vector to express a truncated CBF-B subunit, Bdbd, lacking a transcription activation domain in various mammalian cell lines. The Bdbd polypeptide interacts with cellular CBF-A/CBF-C and binds to promoters containing CBF-binding sites. Interestingly, expression of Bdbd in various mammalian cells resulted in the inhibition of cell proliferation and specific cell cycle arrest at G2/M phase. Gene expression analysis demonstrated that the expression of Bdbd strongly suppressed cell cycle-dependent transcription activation of Cyclin B1, Aurora A and CDK1 genes, key regulators for cell cycle progression at G2/M phase. Chromatin immunoprecipitation analysis showed that Bdbd significantly inhibited binding of TATA-binding protein, TBP to both Cyclin B1 and Aurora A promoters, but did not inhibit binding of E2F3 activator to Cyclin B1 promoter. This study suggested that the activation domain of CBF-B plays an essential role in the transcription activation of Cyclin B1 and Aurora A genes at G2/M phase, thus regulating cell cycle progression at G2/M phase.