EGF/EGFR/ErbB2调控成釉细胞MMP-20基因表达的研究

摘要

AIM:To investigate the roles of EGF/EGFR/ErbB2 signaling pathway in the regulation of matrix metalloproteinase-20 (MMP-20) expression in mouse ameloblasts.METHODS:Mouse ameloblasts were stimulated with 20 ng/mL EGF.MMP-20 expression in ameloblasts was detected by RT-PCR.Changes of MMP-20 promoter was analyzed by dual luciferase reporter analysis.The effects of the inhibitors of EGFR,ErbB2,MAPK signaling pathway and c-Jun pathway on MMP-20 promoter transcription activity were investigated by dual luceferase report gene analysis.RESULTS:EGF enhanced MMP-20 expression and MMP-20 promoter activity before (-157 ～ + 23) region in ameloblasts (P ＜ 0.05).EGFR,ErbB2 and ERK inhibitors attenuated the effects of EGF on MMP-20 expression.C-Jun increased MMP-20 expression through EGFR/ErbB2.Mutation of MMP-20 promoter at AP1 binding site reduced MMP-20 expression.CONCLUSION:EGF can induce MMP-20 expression via EGFR/ErbB2-ERK-C-Jun signaling pathway in mouse ameloblasts.%目的:研究EGF/EGFR/ErbB2信号通路对小鼠成釉细胞中基质金属蛋白酶-20(matrix metalloproteinase-20,MMP-20)基因表达的调控作用.方法:用定时定量RT-PCR、双荧光素酶报告基因检测系统分析EGF/EGFR/ErbB2调控MMP-20基因的表达、EGF调控MMP-20启动子的主要区域、MAPK信号通路阻断剂对EGF调控MMP-20转录活性的影响、转录因子Jun家族介导EGF/ErbB2对MMP-20转录活性的调控;用基因定点突变和双荧光素酶基因检测报告系统分析EGF/ErbB2、C-Jun对MMP-20基因启动子转录活性的影响.结果:成釉细胞经20 ng/mL EGF刺激后,MMP-20的基因表达上调(P＜0.05),MMP-20启动子在(-157～+23)之前的区域转录活性增强(P ＜0.05);EGFR、ErbB2、ERK阻断剂均能抑制EGF对MMP-20基因表达的调控(P＜0.05);转录因子C-Jun介导EGFR/ErbB2上调MMP-20基因的表达(P＜0.05);突变MMP-20启动子的AP1结合位点后,MMP-20基因表达的水平下降(P＜0.05),同时EGF/ErbB2也失去上调MMP-20基因表达水平的作用.结论:在成釉细胞中EGF通过EGFR/ErbB2 ～ ERK～C-Jun信号通路对MMP-20基因的表达起到调控作用.