Fig. (2) HIV LTR driven Cav-1 expression and inhibition of HIV replication. Cav-1 was placed under the control of CMV or the HIV LTR promoter for expression and each was co-transfected with the NL4-3 provirus DNA into 293T cells. HIV replication was monitored by reverse transcriptase activity (A) and the expression of Cav-1 by Western blot analysis (B). A series of Cav-1 and GFP expression cassettes were constructed as depicted in the Figure by placing one IRES (LTR-GFP-IR-Cav1) (C) or two IRES (LTR-IR-GFP-IR-Cav-1) (D). Each of these constructs were co-transfected into 293T cells with or without the Tat expression plasmid, pTatz. The expression levels of Cav-1 and GFP were examined by Western blot analysis 48 hours post transfection. Results are expressed as the means ± standard deviations (SD) from three determinations (P< 0.05).