Figure 1.

One example of the third generation Tat-independent HIV-1 vector system. The shown SIN transfer vector contains the cPPT for efficient nuclear import and uses the MSCV LTR promoter (MU3) as internal promoter for driving the expression of the transgene, as well as the WPRE (W) element for high-level transgene expression. The three other packaging constructs encode for the HIV-1 gag-pol and rev proteins as well as for the VSV-g envelope glycoprotein.²⁰ SIN, self-inactivating; VSV-g, glycoprotein of the vesicular stomatitis virus.