Objectives; To identify the roles of Notch - 1 gene for survivaland differentiation of mesenchymal stem cells ( MSCs) into neurons by way of RNA interference ( RNAi) technique to suppress expression of Notch - 1 gene. Methods; Firstly

construct mNotch - 1 short hairpin RNA (mNotch -IshRNA) and then to oberve configuration of MSCs transfected by mNotch - IshRNA; MTT was employed to evaluate the survival ratio of MSCs before transfection

24 hours and 3 days after transfection

respectively; agents

such as BDNF

retinoid acid

were obtained to induce MSCs transfected by mNotch - IshRNA in vitro and expression of Nestin

NSE and NF200( neuron marker agent) and GFAP( neural glial cell marker agent) were determined by immunocytochemistry stain technique. Results: The cell cubic configuration was enforced and expression of notch - 1 gene vanished by transfection of mNotch -IshRNA. The survival ratio of MSCs by transfection decreased and there was significant differences between non - ransfection and transfection - controlling group after 24 hours and 3 days of transfection ( P <0. 01). The differentiation efficacy of MSCs transfected by mNotch - IshRNA into neurons and the expression of NSE

NF200 were increased significantly than non - ransfection and transfection -controlling group

and there was no expression of GFAP. Conclusions; The differentiation efficacy of MSCs can be enforced by mNotch - IshRNA to suppress Notch - 1 expression

which implies that the transverse differentiation of MSCs is similar to that of neural stem cells. The blocking of Notch - 1 signal pathway might promote differentiation of MSCs into neural stem cells.