The Role of an Inverted CCAAT Element in Transcriptional Activation of the Human DNA Topoisomerase IIα Gene by Heat Shock*
The Role of an Inverted CCAAT Element in Transcriptional Activation of the Human DNA Topoisomerase IIα Gene by Heat Shock*
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反向 CCAAT 元件在热激引起的人类 DNA 拓扑异构酶 IIα 基因转录激活中的作用*
DOI：
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发表时间：
1998
影响因子：
4.8
通讯作者：
K. Kohno
中科院分区：
文献类型：
--
作者：
M. Furukawa;T. Uchiumi;M. Nomoto;H. Takano;R. Morimoto;Seijo Naito;M. Kuwano;K. Kohno
DNA 拓扑异构酶 IIα (topoIIα) 基因的表达对包括热休克在内的各种环境刺激高度敏感。 T24人膀胱癌细胞在43°C热休克应激1小时后，6-24小时后，topoIIα mRNA的量增加了1.5-3倍。通过用含有不同长度的启动子序列的荧光素酶报告质粒瞬时转染T24细胞来研究热休克对人topoIIα基因启动子转录活性的影响。热激应激后24小时，全长启动子（核苷酸（nt）-295至+85）和三个缺失构建体（nt -197至+85、-154至+85和-74至+85）的转录活性增加约3倍。相反，缺少第一个反向CCAAT元件（ICE1）、GC盒以及位于nt -74和-21之间的热休克元件的最小启动子（nt -20至+85）的转录活性并未因热休克而增加。此外，含有GC盒或热休克元件突变的启动子构建体的转录活性，而不是含有ICE1突变的构建体的转录活性，通过热激显着增加。电泳迁移率变动分析显示，当从热激后培养 3-24 小时的细胞中提取核提取物时，核因子与含有 ICE1 的寡核苷酸的结合减少。对于含有 topoIIα 基因启动子热休克元件的寡核苷酸，因子结合没有明显的这种变化。最后，topoIIα基因启动子的体内足迹分析表明，在对照细胞中受保护的ICE1的两个G残基在热激后变得对硫酸二甲酯修饰敏感。这些结果表明，热休克对 topoIIα 基因的转录激活需要 ICE1 释放负调控因子。
Expression of the DNA topoisomerase IIα (topoIIα) gene is highly sensitive to various environmental stimuli including heat shock. The amount of topoIIα mRNA was increased 1.5–3-fold 6–24 h after exposure of T24 human urinary bladder cancer cells to heat shock stress at 43 °C for 1 h. The effect of heat shock on the transcriptional activity of the human topoIIα gene promoter was investigated by transient transfection of T24 cells with luciferase reporter plasmids containing various lengths of the promoter sequence. The transcriptional activity of the full-length promoter (nucleotides (nt) −295 to +85) and of three deletion constructs (nt −197 to +85, −154 to +85, and −74 to +85) was increased ∼3-fold 24 h after heat shock stress. In contrast, the transcriptional activity of the minimal promoter (nt −20 to +85), which lacks the first inverted CCAAT element (ICE1), the GC box, and the heat shock element located between nt −74 and −21, was not increased by heat shock. Furthermore, the transcriptional activity of promoter constructs containing mutations in the GC box or heat shock element, but not that of a construct containing mutations in ICE1, was significantly increased by heat shock. Electrophoretic mobility shift assays revealed reduced binding of a nuclear factor to an oligonucleotide containing ICE1 when nuclear extracts were derived from cells cultured for 3–24 h after heat shock. No such change in factor binding was apparent with an oligonucleotide containing the heat shock element of the topoIIα gene promoter. Finally, in vivo footprint analysis of the topoIIα gene promoter revealed that two G residues of ICE1 that were protected in control cells became sensitive to dimethyl sulfate modification after heat shock. These results suggest that transcriptional activation of the topoIIα gene by heat shock requires the release of a negative regulatory factor from ICE1.
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DOI：
10.1073/pnas.88.16.6911
发表时间：
1991-08-01
影响因子：
11.1
作者：
SCHUETZ, TJ;GALLO, GJ;KINGSTON, RE
通讯作者：
KINGSTON, RE
影响因子：
6.7
作者：
Eisen，Andrew;Nedergaard，Maiken;Kiernan，Matthew C.
通讯作者：
Kiernan，Matthew C.
HL-60 人白血病细胞单核细胞分化早期拓扑异构酶 II α 启动子反式激活。
DOI：
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发表时间：
1995
期刊：
Molecular pharmacology.
影响因子：
--
作者：
Fraser,DJ;Brandt,TL;Kroll,DJ
通讯作者：
Kroll,DJ
DOI：
--
发表时间：
1989
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Travali,S;Ku,DH;Rizzo,MG;Ottavio,L;Baserga,R;Calabretta,B
通讯作者：
Calabretta,B