中文摘要：

摘要：为研究小鼠（Mus musculus）组蛋白H3K4甲基化酶基因Smyd3转录调控的分子机制，本研究首先通过PCR的方法克隆了5条不同长度的Smyd3启动子5’端缺失片段，与pMDl9-T载体连接后，双酶切克隆入pGL3-Basic荧光素酶报告基因载体，构建Smyd3启动子-pGL3-Basic报告基因重组质粒，瞬时转染HEK293细胞48h后采用双报告基因检测试剂盒检测Smyd3启动子各缺失片段的相对荧光活性。结果表明，本研究成功构建Smyd3启动子5’端缺失片段-pGL3-Basic荧光报告基因重组质粒，所构建的启动子重组子转染组与阳性对照组相比表现出荧光活性，并且pGL3-Smyd3-4的荧光活性最强，是其他的2至4倍左右，pGL3-Smyd3-5的荧光活性最弱。本研究初步确定Smyd3基因的启动子核心区域可能位于-533--42bp之间，在-2026--533bp之间可能存在启动子负调控序列。

英文摘要：

To further study the molecular mechanism of transcription regulation of the mouse （Mus musculus） histone H3K4 methylase gene Smyd3, different 5＇-flanking regions of Smyd3 promoter were cloned by PCR and inserted into pMD19-T vector. The pMD19-T vector was digested by two enzymes, and then inserted into pGL3- Basic lueiferase reporter vector. The recombination plasmids were transiently transfected into HEK293 cells, and then its fluorescence activity was measured with the dual-luciferase reporter assay after 48 hours. The results showed that pGL3-Basic-Smyd3-1 - pGL3-Basie-Smyd3-5 lueiferase reporter gene vectors were constructed successfully. Compared with the positive control, construction of promoter reeombinants transfected group showed fluorescenee activity, and the pGL3-Smyd3-4 fluorescence was most active, about 2 -4 times ofthe others, while the pGL3-Smyd3-5 fluorescence activity was the weakest. This study suggests that the core promoter region of the Smyd3 gene may be located on the up-stream between - 533 bp to - 42 bp and that the area between -2 026 bp to -533 bp is a transcriptional negative regulation region.