Objective To construct and identify over-expressing lentiviral vector of m Sema3 A. Methods Sema3 A gene of mice was amplified by PCR,then the gene was inserted into plasmids p Down-m Sema3A-IRES/EGFP by Gateway technology. The plasmids p LV/EXPNZ-puro-m Sema3AIRES/EGFP were produced by recombination. After sequencing identification,the vector p LV(Exp)-Puro-CMV-m Sema3A-IRES/EGFP was packed and condensed. Finally the recombinant vectors were used to transfect 293 T cells to obtain virus pools. Results The ...