Tezel Gülgün, Yang Xiangjun
Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville School of Medicine, Louisville, KY 40202, USA.
Exp Eye Res. 2005 Aug;81(2):207-17. doi: 10.1016/j.exer.2005.01.022.
TNF-alpha has recently been identified to be a mediator of retinal ganglion cell (RGC) death, while glial cells are relatively protected against this death stimulus. To identify molecular mechanisms that control diverse responses of RGCs and glial cells to TNF-alpha, we studied differential gene expression between primary cultures of RGCs and glial cells exposed to TNF-alpha using cDNA array analysis of MAPK and NF-kappaB signaling pathways. Findings of this comparative analysis demonstrated differential regulation of various genes between RGCs and glial cells exposed to TNF-alpha. RT-PCR confirmed the differential expression of selected genes, and immunocytochemistry demonstrated gene products in cultured cells. Immunolabeling with phosphorylation site-specific antibodies also revealed differential post-translational modifications of selected proteins between cell types. Identification of signaling molecules differentially regulated in RGCs and glial cells can improve our understanding of the diverse cellular responses and provide targets for neuroprotective interventions in several neurodegenerative conditions.
肿瘤坏死因子-α（TNF-α）最近被确定为视网膜神经节细胞（RGC）死亡的介质，而神经胶质细胞相对而言能抵御这种死亡刺激。为了确定控制RGC和神经胶质细胞对TNF-α产生不同反应的分子机制，我们使用丝裂原活化蛋白激酶（MAPK）和核因子-κB（NF-κB）信号通路的cDNA阵列分析，研究了暴露于TNF-α的RGC原代培养物和神经胶质细胞原代培养物之间的差异基因表达。这一比较分析的结果表明，暴露于TNF-α的RGC和神经胶质细胞之间各种基因存在差异调节。逆转录聚合酶链反应（RT-PCR）证实了所选基因的差异表达，免疫细胞化学显示了培养细胞中的基因产物。用磷酸化位点特异性抗体进行免疫标记也揭示了不同细胞类型之间所选蛋白质的翻译后修饰差异。确定在RGC和神经胶质细胞中差异调节的信号分子，有助于我们更好地理解不同的细胞反应，并为几种神经退行性疾病的神经保护干预提供靶点。
