Gene Expression of Cell-adhesive Molecule Vitronectin

1.小鼠黑色素瘤细胞整合素αv顺式作用元件的鉴定(首席研究员林正雄教授)我们已经从小鼠基因组文库中克隆了小鼠整合素启动子区域，并测定了转录起始点上游1.8kbp的核苷酸序列(1bp)。我们已经揭示了-108到1bp之间的三个转录调控元件。-27~-16个碱基中的一个与Sp1结合，-61~-54个碱基和-106~-98个碱基中的2个与Ets家族结合。-61至-54bp的元件与Ets-1结合，Ets-1是Ets家族之一。3个顺式作用元件中任何一个的突变或缺失都会显著降低启动子的活性。这些结果表明Sp1和Ets协同激活了109bp的αv启动子区域。Vitronectin启动子区域的特征(研究人员，宫本康成博士)我们发现-19-54bp的区域是小鼠Vitronectin基因转录启动所必需的。这个地区没有塔塔盒子。它与从人肝癌HepG2细胞中提取的核蛋白形成复合体。测定了Vitronectin基因5‘侧翼区-1.8~-3.7kbp之间的核苷酸序列。

1. Identification of cis-acting elements of integrin α v in mouse melanoma cells. (Head Investigator, Prof. Masao Hayashi)We have cloned mouse integrin promoter region from mouse genome library and determined the nucleotide sequence of 1.8 kbp region upstream of the transcription initiation site (+1 bp). We have revealed the three transcriptional regulatory elements between -108 and +1 bp. One element from -27 to -16 bp binds to Sp1, and the two other elements from -61 to -54 bp and from -106 to -98 bp bind to Ets family. The element from -61 to -54 bp binds to Ets-1, one of the Ets family. Mutations or deletions in any one of the 3 cis-acting elements remarkably decreased the promoter activity. These results indicate that Sp1 and Ets cooperate to activate the 109-bp α v promoter region.2. Characterization of vitronectin promoter region (Investigator, Dr. Yasunori Miyamoto)We showed that a region from -19 to +54 bp is essential for the initiation of transcription in mouse vitronectin gene. This region does not have TATA box. It forms a complex with nuclear proteins extracted from human hepatoma HepG2 cells. We determined the nucleotide sequence between -1.8 kbp and -3.7 kbp in 5'-flanking region of vitronectin gene.