FIG. 5.

(A) Western blot analysis of Vpr and VSV-G protein induction. SODk1 cells were induced by doxycycline (DOX) withdrawal and sodium butyrate (BUT) treatment. Three days postinduction, production of the HIV-1 Vpr (lanes 3 and 4) and the VSV-G envelope protein (lanes 1 and 2) in noninduced (lanes 1 and 3) and induced (lanes 2 and 4) cells was determined by Western blot analysis. (B) Northern analysis. Total RNA was extracted from either noninduced SODk1 cells that were cultured in the presence of doxycycline (+DOX) or from SODk1 cells that were induced by doxycycline withdrawal in the presence (−DOX + BUT) or the absence (−DOX) of 5 mM sodium butyrate (upper part of figure). RNA samples were ethidium bromide stained and electrophoresed in a 1.2% agarose gel (lower part of figure). The efficiency of RNA transfer to positively charged membrane was determined by UV fluorescence. The position of the 1.6-kb VSV-G mRNA is indicated with an arrow.