一种AP-2α选择性剪切的发现及其在MCF-7细胞中的功能研究Effect of an alternatively spliced AP-2α on MCF-7 Cells
孙钦升,祖旭宇,于玲玲,蒋宇扬,徐威
SUN Qin-sheng1,ZU Xu-yu2,YU Ling-ling1,JIANG Yu-yang2,XU Wei1(1.School of Life Science and Biopharmaceutics
摘要(Abstract)：
目的研究AP-2α的一种选择性剪切及其对MCF-7细胞生物学功能的影响。方法构建AP-2α基因表达质粒,得到pAP-2α和一个C-端编码产物完全不同于AP-2α的选择性剪切pAP-2αas表达质粒。通过荧光素酶法检测pAP-2αas和pAP-2α对含存活素(survivin)启动子核心序列的荧光素酶报告质粒pLuc-441活性影响的差异;并通过药物敏感性实验观察pAP-2αas和pAP-2α对乳腺癌细胞MCF-7药物敏感性影响的差异。结果采用荧光素酶法检测共转染pAP-2αas和pLuc-441的MCF-7细胞中survivin启动子活性,与对照pAP-2α相比,pAP-2αas也能抑制pLuc-441活性,但抑制的强度低于前者;药物敏感性实验显示,在MCF-7细胞中,转染pAP-2αas显著提高了药物敏感性,与pAP-2α产生的生物学功能近似。结论 AP-2αas作为一种体内的特异性剪切形式,具有和通常AP-2α相似但不完全相同的功能,推测这是基因表达调控的特殊方式,AP-2α对基因表达的调节在某些情况下可以不通过直接结合启动子发挥作用。
Objective To assess the effect of an alternatively spliced AP-2α in MCF-7 cells.Methods AP-2α expression plasmid and an alternatively spliced AP-2α plasmid were constructed.Transient transfection and luciferase assays were performed in MCF-7 cells to assess the effect of AP-2α and alternatively spliced AP-2α on survivin promoter activity.The effects of the two plasmids on chemosensitivity were analyzed in MCF-7 cells by trypan blue staining assay.Results Both in luciferase assay and chemosensitivity analysis,alternatively spliced AP-2α showed similar effect as normal AP-2α in MCF-7 cells.Conclusions Alternatively spliced AP-2α has approximate effect as normal AP-2α,in some cases,AP-2α don′t bind directly to promoter in regulating gene expression.
关键词(KeyWords)：
转录因子激活蛋白2α(AP-2α);选择性剪切;药物敏感性;MCF-7乳腺癌细胞
AP-2α;alternatively spliced;chemosensitivity;MCF-7 cell
基金项目(Foundation): 国家863专题研究资助项目(2007AA02Z160);; 国家自然科学基金资助项目(NSFC:20572060)
作者(Author):
孙钦升,祖旭宇,于玲玲,蒋宇扬,徐威
SUN Qin-sheng1,ZU Xu-yu2,YU Ling-ling1,JIANG Yu-yang2,XU Wei1(1.School of Life Science and Biopharmaceutics
DOI: 10.14066/j.cnki.cn21-1349/r.2010.10.010
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