The ZiN/POZ domain of ZF5 is required for both transcriptional activation and repression
The ZiN/POZ domain of ZF5 is required for both transcriptional activation and repression
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DOI：
10.1093/nar/25.6.1108
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发表时间：
1997-03-15
影响因子：
14.9
通讯作者：
Calame, K
中科院分区：
文献类型：
--
作者：
Kaplan, J;Calame, K
ZF 5是一种广泛表达的蛋白质，最初通过其结合和抑制鼠c-myc启动子的能力来鉴定。它含有5个C-末端锌指和一个保守的N-末端ZiN/POZ结构域。在越来越多的锌指蛋白中发现的这种基序可以抑制DNA结合并介导二聚化[Bardwell，V. J.和Treisman，R. 05 The Dog of the Woman（1994）8，1664-1677]。在目前的研究中，循环扩增和目标选择（CAST）方案检测到高度富含GC的优选ZF 5结合位点。ZF 5与这些位点的结合依赖于锌指，并且当ZiN/POZ结构域被去除时增强。使用瞬时共转染测定，显示ZF 5激活HIV-1 LTR并抑制β-肌动蛋白启动子。ZiN/POZ结构域显示介导ZF 5依赖性转录激活和抑制。从这些数据，我们得出结论，ZF 5可以在不同的天然启动子的背景下激活和抑制，并且其ZiN/POZ结构域可以影响两种功能：DNA结合和转录调节。
ZF5 is a ubiquitously expressed protein originally identified by its ability to bind and repress the murine c-myc promoter. It contains five C-terminal zinc fingers and a conserved N-terminal ZiN/POZ domain. This motif, found in a growing number of zinc finger proteins, can inhibit DNA binding and mediate dimerization [Bardwell, V.J. and Treisman, R. (1994) Genes Dev., 8, 1664-1677]. In the current study a cyclic amplification and selection of targets (CAST) protocol detected preferred ZF5 binding sites which are highly GC-rich. Binding to these sites by ZF5 depended upon the zinc fingers and was enhanced when the ZiN/POZ domain was removed. Using transient cotransfection assays, ZF5 was shown to activate the HIV-1 LTR and repress the p-actin promoter. The ZiN/POZ domain was shown to mediate ZF5-dependent transcriptional activation and repression, From these data, we conclude that ZF5 can both activate and repress in the context of different natural promoters and that its ZiN/POZ domain can affect two functions; DNA binding and transcriptional modulation.