Elucidation of pathogenesis in CAG-repeat diseases using DNA chip

CAG重复序列疾病是由致病基因中CAG重复序列扩增引起的遗传性神经退行性疾病。CAG重复疾病的发病机制仍有待阐明。在这项研究中，我们试图确定CAG重复疾病的相关基因，参与神经变性的CAG重复疾病。我们用腺病毒载体在人神经母细胞瘤（SH-SY 5 Y）中表达扩增的或正常的CAG重复序列（多聚谷氨酰胺序列），建立了体外培养的CAG重复序列病神经元模型。MTS检测显示，感染后细胞核聚集增加，轴突萎缩，细胞活性降低。进一步的DNA芯片分析（包括约10，000个基因）揭示了在扩增的多聚谷氨酰胺表达组中与神经突生长相关的基因的上调，随后用定量真实的时间RT-PCR（Taqmann探针PCR）确认。这一发现与CAG重复疾病动物模型中观察到的轴突萎缩相匹配。

CAG-repeat diseases are inherited neurodegenerative diseases caused by the expansion of CAG repeats in the disease causing genes. The pathogenesis of CAG-repeat diseases remains to be elucidated. In this study, we tried to identify CAG repeat disease-related genes which are involved with neurodegeneration in CAG-repeat diseases. We made in vitro CAG-repeat disease neuronal culture model using adenovirus vectors, which expressed expanded or normal CAG repeat (polyglutamine tract) in human neuroblastoma (SH-SY5Y). This model showed increasing of nuclear aggregates after infection, axonal atrophy and decreasing of cellular activity detected with MTS assay. Further DNA chip analysis (including about 10,000 genes ) revealed upregulation of a gene associated with neurite outgrowth in expanded polyglutamine-expressed group, followed by confirmation with quantitative real time RT-PCR (Taqmann probe PCR). This finding is matched with axonal atrophy observed in CAG-repeat disease animal model.