MPG, HIV related is 27-aa peptide vector, derived from both the nuclear localisation sequence of SV40 large T antigen and the fusion peptide domain of HIV-1 gp41 and is a potent delivery agent for the generalised delivery of nucleic acids and of oligonucleotides into cultured cells and for gene therapy. MPG enables complete expression of the gene produces encoded by the plasmids it delivers into cultured cell.