热休克因子1对FasL的调控作用

The transcription regulation of HSF1 on FasL

目的研究人热休克因子1(HSF1)对Fas配体(FasL)启动子转录活性的影响。方法用在线启动子分析软件分析FasL启动子区转录因子结合位点;凝胶阻滞实验(EMSA)研究内源性HSF1与FasL启动子区的热休克元件(HSE)结合能力;将组成型活化的HSF1突变体与FasL启动子表达载体FasL-luc共同转染HeLa细胞,采用双荧光素酶报告基因检测系统,检测荧光索酶活性。结果在FasL启动子区发现HSE核心序列(nGAAnnTTCn),HSF1可以与该HSE体外结合;荧光素酶活性测定发现HSF1明显上调FasL-luc转录活性,突变该HSE,则转录激活作用消失。结论 HSF1对FasL具有转录调控作用。

Objective To explore the transcription regulation and molecular mechanism of heat shock factor 1 （HSF1） on Fas ligand of human and mouse. Methods The conserved region within FasL promoter upstream of the translational start site that contains heat shock element （HSE） was analyzed. DNA binding activity of HSF1 on the HSE of FasL promoter was studied by electrophoretic mobility shift assay （EMSA）.HeLa cells transiently transfected with pcDNA or pcDNA- HSFld203-315 and pGL3-FasL.Dual-luciferase reporter assay was used to study the transcriptional activity of HSF1 among different groups. Results HSE consists of one perfect nGAAn pentamers, housed within the proximal region of the FasL promoter. HSF1 can directly bind to this element and upregulated transcriptional activity of FasL promoter. The mutation of HSE can abrogate the ability of HSF1 to bind and abrogate the promoter activity. Conclusion HSF1 induce transactivation activity of FasL.