Figure 1.

Recruitment of CycT1/P-TEFb activates the HIV-1 LTR promoter independently of Tat and TAR. 293T cells were transfected with HIV-1 LTR-based reporter plasmids containing the TAR (a) or SLIIB (b) RNA target. Transactivation by the indicated effectors, expressed either as wild-type unfused proteins or fused to Rev, was determined by measuring CAT levels 48 hr after transfection. In c, cells were transfected with the pHIV/SLIIB/CAT reporter plasmid, along with plasmids expressing hCycT1-Rev and the indicated wild-type or mutant Tat expression plasmid. In each case, results represent the mean ± standard deviation of three transfections.