Figure 1
From: Lentiviral vector design using alternative RNA export elements
Schematic of a panel of transfer plasmids containing different cis -acting DNA elements: Role on viral titer and transduction efficiency. The basic lentiviral transfer plasmid used in this experiment were derivatives of the pHRSVcPGKnlsLacZR(-)W(-), which contains the murine PGK promoter driving the expression of the nuclear localized lacZ gene (nlsLacZ). The central polypurine tract sequence (cppt; GREY box) was cloned into all of the lentiviral transfer plasmids to maximize transduction efficiency. Splice donor (SD and acceptor (SA) sites were included in every transfer plasmid. Viral titer was determined by end-point dilution on HeLa cells, and p24 Gag protein levels were determined by ELISA. C = constitutive transport element; WPRE = woodchuck post-regulatory element; RRE = rev-responsive element; SIN LTR = 3' self-inactivating long-terminal repeat. n = 4–8 different lentiviral preparations/transfer plasmid. * p < 0.05 difference between the basic lentiviral vector (pHRSVcPGKnlsLacZR(-)W(-).