Influence of the content in transcription factors on the phenotype of mouse hepatocyte-like cell lines (mhAT).
Influence of the content in transcription factors on the phenotype of mouse hepatocyte-like cell lines (mhAT).
复制标题
转录因子含量对小鼠肝细胞样细胞系（mhAT）表型的影响。
DOI：
10.1006/excr.1993.1315
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发表时间：
1993
影响因子：
3.7
通讯作者：
B. Antoine
中科院分区：
文献类型：
--
作者：
F. Levrat;V. Vallet;T. Berbar;L. Miquerol;A. Kahn;B. Antoine
我们已经描述了新的分化良好的小鼠肝细胞样细胞系（mhAT）来源于抗凝血酶III基因启动子控制下表达猿猴病毒40大T抗原的转基因小鼠（Exp.（1992）200，175-185）。为了了解不同细胞系的表型变异，我们分析了它们在肝脏特异性转录因子中的含量，蛋白质水平，通过凝胶位移分析，mRNA水平，通过定量逆转录PCR。此外，内源性HNF 1 α和C/EBP α的反式激活能力也通过测量由TATA盒上游的DNA元件均聚物组成的转染的合成启动子的活性来评价。在mhAT细胞中维持高水平的HNF 1、HNF 3和HNF 4转录因子。相比之下，C/EBP α在不同细胞系之间的变化要大得多，并且在肝脏中的丰度低于体内。我们研究了HNF 1 α和C/EBP α对转染的肝特异性启动子活性的影响。HNF 1 α不限制转染的肝型丙酮酸激酶和白蛋白启动子的活性。相比之下，在不同的线路，白蛋白启动子的活性明显依赖于C/EBP α的内容，这似乎是一个重要的因素，因此，在HNF 1 α含有细胞中调节该基因的表达。这项工作表明，在一组分化良好的培养细胞中，启动子活性和反式作用因子含量之间的相关性可用于确定转录因子对某些启动子强度的各自作用。
We have described new well-differentiated mouse hepatocyte-like cell lines (mhAT) derived from transgenic mice expressing simian virus 40 large T antigen under the control of antithrombin III gene promoter (Exp. Cell Res. (1992) 200, 175-185). In an attempt to understand the phenotypic variations of the different cell lines, we analyzed their content in liver-specific transcription factors at the level of both the proteins, by gel shift analysis, and the mRNA, by quantitative reverse-transcription PCR. Moreover, the transactivating ability of endogenous HNF1 alpha and C/EBP alpha was also evaluated by measuring the activity of transfected synthetic promoters consisting of DNA element homopolymers upstream of a TATA box. High levels of HNF1, HNF3, and HNF4 transcription factors were maintained in mhAT cells. In contrast, C/EBP alpha was much more variable between the different cell lines and was less abundant than it was in vivo, in the liver. We investigated the influence of HNF1 alpha and C/EBP alpha on the activity of transfected liver-specific promoters. HNF1 alpha was not limiting for the activity of transfected liver-type pyruvate kinase and albumin promoters. In contrast, the activity of the albumin promoter in the different lines was clearly dependent on the C/EBP alpha content, which seems, therefore, to be an essential factor modulating the expression of this gene in HNF1 alpha-containing cells. This work shows that the correlations between promoter activities and transacting factor contents in a panel of well-differentiated cultured cells can be used to determine the respective role of transcription factors on the strength of some promoters.