Objective      To construct a recombinant eukaryotic vector expressing rat Jagged1

and to explore the effect of Jagged1 over-expression on the proliferation and apoptosis of vascular smooth muscle cells (VSMCs).     Methods      The full-length fragment of Jagged1 gene was obtained from the plasmid pBOS-SN3T(encoding rat Jagged1) by digestion. A eukaryotic vector expressing rat Jagged1 (p-rJagged1) was constructed with the aid of the plasmid pCMV-IRES-GFP

and then the vectors were t

ransfected into VSMCs. The expression of Jagged1 protein was detected by Western blotting. The proliferation of VSMCs was observed by assessing the incorporation of

3

H-thymidine. The apoptosis of VSMCs was analyzed by flow cytometry.     Results      Recombinant plasmid p-rJagged1 was successfully constructed and transfected into VSMCs. The efficiency of transfection was over 90% after G418 screening. The protein levels of Jagged1 were increased by almost 6 folds after transfection. The proliferation of VSMCs was significantly lower[(10 265±1 004) vs (17 584±1 587) cpm/well

P0.01

]

and the apoptotic rate of VSMCs was significantly higher[total rate of apoptosis: (32.35±2.86)% vs (15.24±1.27)%; early rate of apoptosis: (22.47±2.54)% vs (10.22±0.98)%; P0.01

]

in the p-rJagged1 transfected group compared with those in the untransfected group.     Conclusion      A recombinant eukaryotic vector expressing rat Jagged1 is constructed. Jagged1 over-expression can suppress the proliferation and promote the apoptosis of VSMCs.