Fig. 1.

Stable gene expression systems. a Representation of simple (e.g. MLV) and complex (e.g. HIV-1) retroviral genomes. b Lentiviral production of 3rd generation vectors and cell transduction. Plasmids containing expression constructs of genetic elements required for packaging (gag-pol, rev and VSV-G, a gene encoding the fusogenic envelope G glycoprotein of the vesicular stomatitis virus) and a plasmid of interest comprised of a chimeric 5′ LTR (long terminal repeat) fused to a heterologous promoter (hP), a promoter (P) to control transgene expression and 3′ Self-inactivating (SIN) LTR are co-transfected together into a producer cell line. After viral production, transduction of lentivector is performed on the target cell. c Cut-and-paste mechanism of SB transposons, where a transposon in a plasmid and a transposase binds to two inverted terminal repeats (ITRs) of the transposon, and precisely cuts the transposon out of the plasmid, inserting the transposon into DNA of the target cell. SB transposons, integrate into TA dinucleotide base pairs, which are duplicated on each end of the insertion site