乙型肝炎病毒X蛋白抑制SFRP5启动子的活性  

Repression of SFRP5promoter activity by hepatitis B virus X protein

作　　者：陈林林[1] 谢青[1] 单晓亮[1] 权会琴[1] 陈庆美[1] 周帆[1] 聂丹[1] 唐霓[1] 

机构地区：[1]重庆医科大学感染性疾病分子生物学教育部重点实验室,重庆400016

出　　处：《中国病理生理杂志》2013年第2期200-204,共5页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.31171307;o.30972586)

摘　　要：目的:探讨乙型肝炎病毒X蛋白(HBx)抑制分泌型卷曲相关蛋白5(SFRP5)启动子活性的分子机制。方法:扩增不同长度的SFRP5启动子区片段,构建到萤光素酶报告基因载体pGL3-Basic上,并将构建好的重组质粒转染入正常肝细胞系LO2细胞,再分别感染编码HBx的腺病毒(Ad-HBx)或编码绿色荧光蛋白的腺病毒(Ad-GFP),荧光显微镜下观察病毒感染效率,检测萤光素酶活性以观察HBx对SFRP5启动子活性的影响。结果:(1)含不同长度的SFRP5启动子区截短突变报告质粒构建成功。(2)截短突变报告质粒的萤光素酶活性与pGL3-Basic对照组相比,分别为(6.32±0.04)倍(-478 bp～+47 bp)、(5.79±0.32)倍(-811 bp～+47 bp)、(3.59±0.34)倍(-1 235 bp～+47 bp)、(3.86±0.39)倍(-1 677 bp～+47 bp)、(3.26±0.42)倍(-2 072 bp～+47 bp)(均P<0.05)。过表达HBx可以明显抑制SFRP5启动子活性,抑制率分别为44%(-478 bp～+47 bp)(P<0.05)、46%(-811 bp～+47 bp)(P<0.05)、28%(-1 235 bp～+47 bp)、24%(-1 677 bp～+47 bp)和40%(-2 072 bp～+47 bp)。结论:HBx可以明显抑制SFRP5启动子区活性,可能导致SFRP5基因表达下调。AIM： To investigate the molecular mechanism that hepatitis B virus X protein （HBx） inhibits the promoter activity of secreted frizzled-related protein 5 （SFRPS）. METHODS ： Serial truncated fragments of SFRP5 pro- moter were amplified and cloned into luciferase reporter vector pGL3-Basic. LO2 cells were transfected with recombinants, and then infected with the adenoviral vector expressing HBx protein （Ad-HBx） or the analogous adenovirus expressing green fluorescent protein （Ad-GFP） for control. The infection efficiency was examined under a fluorescence microscope and the activity of SFRP5 promoter was measured by luciferase assay. RESULTS： Truncated fragments of SFRP5 promoter were successfully constructed. Compared with the pGI3-Basic control, the luciferase activity was 6.32 ＋ 0.04 of the - 478 bp ~ ＋ 47 bp fragment, 5.79 ＋ 0.32 of the - 811 bp ~ ＋ 47 bp fragment, 3.59 ＋ 0.34 of the - 1 235 bp - ＋ 47 bp frag- ment, 3.86 ＋ 0.39 of the - 1 677 bp - ＋ 47 bp fragment and 3.26 ＋ 0.42 of the - 2 072 bp - ＋ 47 bp fragment, respec- tively. Overexpression of HBx inhibited the activity of SFRP5 promoter. The average inhibitory rates were 44% for - 478 bp ~ ＋47b, 46% for -811 bp- ＋47 bp, 28% for -1 235 bp- ＋47 bp, 24% for -1 677 bp ~ ＋47 bp and 40% for - 2 072 bp - ＋ 47 bp, respectively. CONCLUSION： HBx suppresses the activity of SFRP5 promoter, leading to down- regulation of SFRP5 expression.

关 键 词：乙型肝炎病毒X蛋白 分泌型卷曲相关蛋白5 启动子区 

分 类 号：R373.21[医药卫生—病原生物学] R394.3[医药卫生—基础医学]