作　　者： ; ; ; ;

机构地区： 北京大学生命科学学院

出　　处： 《生物化学与生物物理学报》 2003年第6期522-528,共7页

摘　　要： 金属硫蛋白 3(MT 3) ,又称神经生长抑制因子 ,主要表达于中枢神经系统。它属于金属硫蛋白家族 ,但具有几项其他家族蛋白质如MT 1/ 2等所不具有的独特性质 ,是一种多功能蛋白质 ,可在中枢神经系统中发挥重要的神经调节和神经保护作用 ,但是具体发挥机制还很不清楚。实验以人神经母细胞瘤细胞系SH SY5Y为模型 ,运用最近发展起来的比较蛋白质组学研究方法对MT 3基因瞬时转染引起的SH SY5Y细胞蛋白质的整体变化进行了系统的研究。经考马斯亮蓝染色 ,结果表明 ,MT 3转基因后平均每块胶上可检测到约 75 0个蛋白质点。利用ImageMaster 2DElite软件对胶上的蛋白质点进行半定量分析 ,发现共有 17个蛋白质点呈显著的变化 :和对照组比较 ,在这 17个点中 ,有 12个表达明显上调 ,有 5个表达水平明显下降 ,实验结果具有可重复性。结合pI值和分子量 ,应用基质辅助激光解吸 /电离飞行时间质谱对这 17个点进行分析 ,鉴定了其中 10个点 ,包括类锌指蛋白 ,谷氨酸转运蛋白和增强蛋白等。这些蛋白质都可在神经系统功能的调节中发挥作用。实验结果表明MT 3可能是通过调节和 /或协同这些蛋白质来发挥它的多种功能的。 Metallothionein-3(MT-3), also known as growth inhibitory factor (GIF), is predominantly expressed in central nervous system (CNS). It belongs to the family of metallothionein(MT) but has several unique properties that are not shared by other family members such as MT-1/MT-2. In the past few years, MT-3 had been postulated to be a multipurpose protein which could play important neuromodulatory and neuroprotective roles in CNS besides the common roles of MTs. However, the primary function of MT-3 and the mechanism underlying its multiple functions were not elucidated so far. In present study, human neuroblastoma cell line SH-SY5Y was employed to study the overall cellular protein changes induced by transient transfection of MT -3 gene, based on comparative proteome analysis. Averagely about 750 spots were visualized by Coomassie staining in one 2D gel, in which 17 proteins were shown to display significant and reproducible changes by semiquantitative analysis with ImageMaster 2D Elite software. Among them, 12 proteins were up-regulated while other 5 proteins were down-regulated. Using matrix-assisted laser desorption/ionization time- of-flight mass spectrometry, 10 proteins were further identified to be zinc finger protein, glutamate transporter, and enhancer protein, etc ., which were involved in several important pathways regulating the functions of central nervous system. The results showed that MT-3 might exert its unique functions by regulating the expression of these proteins.

关 键 词： 金属硫蛋白 细胞转染 双向电泳 基质辅助激光解吸 电离飞行时间质谱 系

领　　域： [生物学]