(A) MT4 cells expressing doxycycline-inducible shRNA against HLTF together with RFP were obtained under puromycine selection. Percentage of RFP-positive cells expressing shRNA was determined by flow cytometry (NTd, nontransduced cells; shCtrl, cells transduced with a control shRNA; and shHLTF, cells transduced with an shRNA against HLTF). Data show a mean of three experiments ± SD. (B) The presence of Vpr or the absence of HLTF did not alter infection by HIV-1. Cells were infected with VSV-G pseudotyped NL4-3 viruses expressing or not Vpr [NI, noninfected; NL WT, cells infected with NL4-3 (VSV) expressing Vpr; and NL ∆Vpr, cells infected with NL4-3 (VSV) lacking Vpr]. Infection levels were assessed by measuring Gag expression by flow cytometry at 24 and 48 h postinfection (pi). Data show a mean of three experiments ± SD.