RORγt基因启动子的鉴定和特征分析  

Identification and characteristic analysis of RORγt gene promoter region

作　　者：杨丽霞[1] 黄朝峰[1] 

机构地区：[1]中山大学中山医学院人类病毒研究所,广州510080

出　　处：《免疫学杂志》2013年第1期28-32,共5页Immunological Journal

基　　金：国家自然科学基金项目(31170831);广东省引进创新科研团队计划资助项目(2009010058)

摘　　要：目的以RORγt转录起始位点5’上游4.8 kb基因序列为研究对象,初步鉴定分析是否存在RORγt单独的启动子,并且探讨β-Catenin/Tcf1信号途经对RORγt启动子转录活性的影响。方法用带有不同长度的5’上游基因的5个报告质粒,与pSV-40-renilla Luc共转染Jurkat、EL-4、NIH 3T3和293T细胞系,与报告质粒的空载相比较,根据荧光强度的相对值的大小确定启动子存在的可能性和所在的位置;利用野生型β-Catenin、激活突变型β-Catenin和Tcf1表达质粒及RORγt启动子报告载体共转染,观察β-Catenin/Tcf1信号途径对RORγt启动子活性的影响。结果不同长度的启动子报告质粒在Jurkat、EL-4、NIH 3T3和293T细胞中均呈现启动子活性,其中所有报告质粒在Juakat和EL-4等T细胞系中的活性均高于其他2个上皮细胞系,而RORγt上游0.5 kb的报告质粒启动子活性在所有的细胞系中均呈最高活性。野生型β-Catenin、激活突变型β-Catenin和Tcf1对RORγt启动子报告有强激活作用。结论 RORγt转录表达由独立启动子控制,β-Catenin/Tcf1信号途径能够增强该启动子的转录活性。In this study, we would like to identify and analyze the promoter characters of RORγt gene 5＇- flanking region, and to reveal the transcriptional regulation of RORγt gene expression. Five reporter vectors containing different fragments of RORγt gene 5＇-flanking region in pGL-3 luciferase were co-transfeeted with pSV-40-renilla Luciferase reporter vector into Jurkat, EL-4, NIH 3T3 and 293T cells. Promoter activity has been measured and compared to the blank reporter vector in different cells. Our studies demonstrated that these regions displayed higher promoter activity in T cell-derived EL-4 and Jurkat cell than that in non-T cell derived 293T and NIH 3T3 cells, and the relative promoter activity of pGL3-pRORγt-0.5 kb was the highest in all cells. The result implied that RORγt gene expression could be regulated by a potential promoter located in the upstream of RORγt gene transcription start site. Also our study demonstrated β-Catenin/Tcfl could stimulate RORγt promoter activity dramatically. Thus our study suggested there was a potential promoter located in RORγt up-stream transcription start site, and β-Catenin/Tcfl signaling pathway can enhance the transcriptional aetivity of this promoter region.

关 键 词：RORΓT 启动子分析 转录调控 Β-CATENIN Tcf1信号途径 

分 类 号：R440[医药卫生—诊断学]