A retinoic acid-responsive element is present in the 5' flanking region of the laminin B1 gene.
A retinoic acid-responsive element is present in the 5' flanking region of the laminin B1 gene.
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DOI：
10.1073/pnas.86.23.9099
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发表时间：
1989-12
影响因子：
11.1
通讯作者：
George W. Vasios;Joseph D. Gold;M. Petkovich;P. Chambon;L. Gudas
中科院分区：
文献类型：
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作者：
George W. Vasios;Joseph D. Gold;M. Petkovich;P. Chambon;L. Gudas
视黄酸（RA）相关的小鼠F9畸胎瘤干细胞分化的基因表达的显着变化的结果。编码细胞外基质蛋白层粘连蛋白的B1亚基的细胞基因被RA转录激活，并且在F9干细胞分化为胚外壁内胚层细胞期间，其转录被N6，O2 '-二丁酰腺苷3'，5 '-环一磷酸（Bt 2cAMP）进一步增强。我们现在报道了编码人RA受体RAR-α、RAR-β和RAR-γ的表达载体可以激活来自层粘连蛋白B1启动子/CAT表达载体（例如，p1.6LAMCAT），如在瞬时转染测定中测量的。Bt 2cAMP不进一步增强RA相关的CAT活性增加。通过使用缺失和突变分析，鼠层粘连蛋白B1基因的RA反应元件（RARE）已被定义为层粘连蛋白B1 5'侧翼区的-477和-432之间的46个碱基对元件。将含有该RARE的DNA区域以任一方向插入胸苷激酶启动子/CAT表达载体中，可导致CAT表达在RA处理的F9细胞中被共转染的人RAR-α或RAR-β构建体激活5至9倍，并且该RARE也在人HeLa细胞中起作用。相反，当在甲状腺激素存在下与c-erbA基因共转染到F9干细胞中时，p1.6LAMCAT载体中的RARE不激活CAT表达。这表明层粘连蛋白B1基因在体内被RA激活，而不是被甲状腺激素激活。
The retinoic acid (RA)-associated differentiation of murine F9 teratocarcinoma stem cells results in dramatic changes in gene expression. The cellular gene encoding the B1 subunit of the extracellular matrix protein laminin is transcriptionally activated by RA, and its transcription is further enhanced by N6,O2'-dibutyryladenosine 3',5'-cyclic monophosphate (Bt2cAMP) during the differentiation of F9 stem cells into extraembryonic parietal endoderm cells. We now report that expression vectors encoding the human RA receptors RAR-alpha, RAR-beta, and RAR-gamma can activate chloramphenicol acetyltransferase (CAT) expression from laminin B1 promoter/CAT expression vectors (e.g., p1.6LAMCAT) in RA-treated F9 cells, as measured in a transient transfection assay. Bt2cAMP does not further enhance the RA-associated increase in CAT activity. Through the use of deletion and mutation analyses, the RA-responsive element (RARE) of the murine laminin B1 gene has been defined as a 46-base-pair element between -477 and -432 of the laminin B1 5' flanking region. Insertion of a region of DNA containing this RARE in either orientation into a thymidine kinase promoter/CAT expression vector causes CAT expression to be activated 5- to 9-fold by the cotransfected human RAR-alpha or RAR-beta constructs in RA-treated F9 cells, and this RARE also functions in human HeLa cells. In contrast, this RARE in the p1.6LAMCAT vector does not activate CAT expression when cotransfected into F9 stem cells with the c-erbA gene in the presence of thyroid hormone. This suggests that the laminin B1 gene is activated by RA but not by thyroid hormone in vivo.