中文摘要：

LeY是一种双岩藻糖化寡糖,在大多数上皮来源的肿瘤细胞（包括乳腺癌、卵巢癌等）中高表达.岩藻糖基转移酶Ⅳ（fucosyltransferaseⅣ,FUT4）是合成LeY的关键酶.前期工作发现,FUT4通过增加LeY糖的合成来促进细胞的增殖.但有关FUT4的转录调控机制尚不清楚.本文通过对人FUT4基因近端启动子进行生物信息学分析,并构建不同长度启动子序列荧光虫荧光素酶报告基因表达载体,分析其转录活性.使用First EF程序分析并获得FUT4近端启动子序列,采用PCR法扩增FUT4基因近端不同长度的启动子序列,定向克隆,获得不同长度的启动子重组质粒.重组质粒经双酶切及测序鉴定正确.荧光素酶活性分析不同长度的FUT4基因启动子片段的转录活性.结果显示,pGL6-FUT4-1.2 kb在MCF-7和MDA-MB-231细胞中转录活性明显升高（P〈0.05）.说明FUT4基因启动子区域定位于转录起始位点上游的-800～-1 600 bp的区域内.

英文摘要：

LeY is a difucose oligosaccharide highly expressed in the most cancer in the epithelial tissues,such as breast cancer,ovarian cancer.Fucosyltransferase Ⅳ（FUT4） is the key enzyme for synthesis of LeY.Previous study showed that FUT4 improved the cell proliferation through increasing the synthesis of LeY.But the mechanism of transcription regulation of FUT4 remained unclear.In this study,we constructed plasmid with report gene containing FUT4 promoter segments with different lengths according to the bioinformatics analysis and identified their transcriptional activities in different cell lines.Sequence of FUT4 promoter was obtained according to the analysis of First EF program.Human FUT4 promoter segments in different lengths were amplified by PCR.The products of PCR were cloned into pGL6 vector after double digestion by KpnⅠ and NheⅠ,and the recombinant plasmid of different promoter length were obtained,respectively.The recombinant plasmid was transfected into MCF-7 cells and MDA-MB-231 cells with lipofectamine 2 000.The transcriptional activities were analyzed by double luciferase method.The luciferase activities of pGL6-FUT4-1.2 kb was increased in both cell lines（P0.05）.The sequence-800~-1 600 bp may be responsible for the transcriptional activities of FUT4.