Human or mouse microRNA precursors and their native context sequences (upstream and downstream flanking genomic sequences) were PCR amplified, and cloned into a pLenti-TetCMV(GFP-Stop-3UTR/miRNA)-Rsv(Puro) lentivector. The GFP and pre-miRNA are co-transcribed under the same promoter, the optional inducible CMV promoter. The GFP provides a convenient indicator for miRNA expression levels. A puromycin antibiotic selection marker provides the selection method for long term stable expression. See the scheme below for the core vector structure.