JUN and infection: To test the importance of these transcription factors (NF-κB, Sp1, and AP-1) in the activation of unintegrated HIV-1 DNA in PTEN-KO cells, we individually knocked down the expression of RELA (a subunit of the NF-κB), Sp1, and JUN (a member of AP-1) in HeLa cells using siRNAs (Figure 3A), and then challenged each culture by infection with integrase-deficient (IND64A) HIV-Luc reporter virus.