关键词: ：Sim2, PC12细胞, Synapsin I, GAP43

Abstract: [Abstract] Objective To observe the effect of Sim2 gene transfection on the differentiation of PC12 cells, and to explore the role of Sim2 in the pathogenesis of Down syndrome. Methods PC12 cells were transfected with the pcDNA3-mSim2 plasmid by LipofectamineTM reagent and selected with G418. The morphology of PC12 cells was observed by phase-contrast microscope. The mRNA expression of mSim2, GAP43 and Synapsin I was determined by reverse transcription-polymerase chain reaction (RT-PCR). GAP43 protein expression was detected by flow cytometry. Results Abundant mSim2 expression in the pcDNA3-mSim2 transfected PC12 cells was confirmed by RT-PCR, which suggested a successful transfection. In the cells transfected with pcDNA3-mSim2, there were less neuritis, and the length of neurites was shorter. The mRNA expression of GAP43 and Synapsin I was significantly decreased. Upon flow cytometry, the GAP43 protein expression was significantly suppressed by mSim2 transfecton. Conclusion Sim2 may play an important role in the pathogenesis of Down syndrome by influencing the neurite growth and inhibiting the differentiation of neurons.