目的 探讨家族性阿尔茨海默病(Alzheimer's disease,AD)相关的早老素1(presenilin-1,PS-1)V97L突变引起胰岛素降解酶(insulin degrading enzyme,IDE)降低的机制.方法 应用转录因子活性芯片技术检测转录因子活性的差异,再用Western b1ot法验证芯片结果.结果 芯片结合MatInspector软件分析发现,上调了5.5倍的转录因子GATA结合蛋白3(GATA binding protein 3,GATA-3)在IDE启动子上有结合位点,并对IDE起负性调控作用.Westem b1ot也证实稳定转染PS-1 V97L细胞系中GATA-3蛋白表达明显增高.结论 PS-1 V97L突变可能通过上调转录因子GATA-3抑制IDE的表达,影响β-淀粉样蛋白42含量进而参与AD的发生.
Objective To investigate the mechanisms of decreasing insulin degrading enzyme (IDE) level by mutation V97L in the gene presenilin 1 (PS-1).Methods Transcription factor GATA binding protein 3 (GATA-3) activity was assessed by protein/DNA array and verified by Western blot in SH-SY5Y cells transfected by PS-1 mutation V97L.Results Protein/DNA array and Western blot revealed that there was increased transcript factor activity (5.5 times high) and protein level of GATA-3 in V97L-PS-1 transfected SH-SY5Y cells.Transcription factor GATA-3 can bind to the IDE promoter and negatively control the IDE transcription level.Conclusion PS-1 mutation V97L may regulate the transcription of IDE via GATA-3, and subsequently involve in deposition of Aβ42 and development of Alzheimer's disease.