Construction of eukaryotic expression vector of mouse microRNA miR-21 and identification its expression activity in 293 cells

Objective To construct the eukaryotic expression vector for mouse microRNA miR-21 and identification its expression activity in 293 cells.Methods The genomic sequence containing pre-miR-21 was amplified from mouse genomic DNA by PCR and cloned into the pRC / CMV plasmid.The constructed recombinant plasmid pRC / CMV-mmu-miR-21 was transfected to 293 cells by lipofectamine 2000,and the stably transfected cells were screened with G418,from which total RNA was extracted for detecting the expression of mature miR-21 by northern blot.In the meantime,a luciferase report plasmid examing the activity of miR-21 named pmiR-21-Luc reporter was also constructed,and luciferase activity analysis indicated the product of pRC / CMV-mmu-miR-21 indeed had biological activity.Results Both restriction enzyme digestion analysis and sequencing proved the recombinant plasmids were constructed correctly.The miR-21 was highly expressed in the screened clones of 293 cells and it had good biological activity.Conclusion The eukaryotic expression plasmid of mouse miR-21 was successfully constructed,which laid the foundation of further investigation of the role of miR-21 during skin wound healing.