Figure 1

Effects of DSB on HIV-1 VLP production by (A) insect cells and (B) mammalian cells. (A), Sf9 cells infected with AcMNPV-Pr55Gag were treated with increasing concentrations of DSB in DMSO-aliquots for 30h at 18h pi, as indicated on top of the panels. Cells were harvested at 48 h pi, and whole cell lysates (WCL) and extracellular VLP recovered from the culture medium were analyzed by SDS-PAGE and immunoblotting using anti-Gag polyclonal antibody and phosphatase-labelled anti-rabbit IgG antibody. (i), WCL. (*), Asterisk marks posttranslationally modified Gag precursor (ubiquitinated and/or phosphorylated). This Gag species was not included in the quantification of Pr55Gag polyprotein. (ii), Extracellular VLP. (B), 5BD.1 packaging cells were treated with increasing DSB concentrations in DMSO for 30 h, as indicated on top of the panels, and cells and VLP collected separately and analyzed as above. (i), WCL; (ii), VLP. (iii), Same experiment as in (ii), except for the immunoblot analysis, which was performed using ³⁵S-labelled secondary antibody. Shown in (iii) is an autoradiogram of the blot. Molecular markers (m) were electrophoresed on the left side of the gels, and their molecular masses are indicated in kiloDaltons (kDa).