中文摘要：

目的确定转录因子Snail可与PRL-3基因启动子区结合。方法应用生物信息学方法获得PRL-3基因启动子区域，并对其潜在的Snail结合位点进行预测，进一步应用Snail抗体染色质免疫共沉淀技术结合PCR技术检测PRL-3基因启动子序列，以确定转录因子Snail可与PRL-3基因启动子结合。结果应用TRED在线分析系统确定PRL-3基因的启动子区域位于PRL-3基因上游-700bp至299bp之间，在该启动子区域存在多个转录因子如Snail、n—MYC、ARNT、E74A、NF—kappaB、NRF-2及AML-1等的结合位点；在启动子区域的-500bp至-451bp之间存在Snail结合的核心寡核苷酸序列CACCTG，在其他多个区域存在多个类似这一核心序列的DNA序列；应用染色质免疫沉淀技术结合PCR扩增的方法对人大肠癌细胞株SW480细胞进行分析，发现Snail可与人大肠癌细胞株SW480PRL-3基因的启动子区域的DNA片断结合。结论转录因子Snail可与人大肠癌细胞SW480PRL-3基因启动子结合，参与PRL-3基因的调控。

英文摘要：

Objective To identify the region in PRL-3 gene promoter where the transcriptional factor Snail can bind. Methods PRL-3 promoter and the possible binding sites of the transcription factors were analyzed by bioinformatical methods. Chromatin immunoprecipitation and PCR were performed using the antibody specific for Snail to verify the binding of Snail to PRL-3 promoter. Results According to the prediction by TRED, a promoter prediction software, PRL-3 gene promoter was located between -700 bp to 299 bp of PRL-3 gene. Many possible transcription factor binding sites such as for Snail, n-MYC, ARNT, E74A, NF-kappaB, NRF-2 and AML-1 were predicted by Consite, a promoter analysis web system. Interestingly, a 5＇-CACCTG-3＇ core sequence and other related sequences of Snail binding sites were found in the promoter region of PRL-3 genes by Consite software. Two regions in PRL-3 promoter were validated to allow binding of Snail by chromatin immunoprecipitation analysis of SW480 cells. Conclusion Snail regulates the activity of PRL-3 gene by binding to the promoter of PRL-3 gene in SW480 cells.