Modulation of NF-κB activity by primate lentiviral Vpr proteins.

<p>HEK293T cells were cotransfected with the indicated <i>vpr</i> alleles, a firefly luciferase reporter construct under the control of three NF-κB binding sites, and a <i>Gaussia</i> luciferase construct for normalization. In the middle and bottom panels, cells were additionally stimulated with TNFα or cotransfected with a constitutively active mutant of IKKβ (c.a. IKKβ), respectively. Luciferase activities were determined 40 hr post-transfection. All values (including the no inducer controls) are shown as percentage of the vector control, which was set to 100%. Mean values of three to ten independent experiments in triplicates ± SEM are shown. Asterisks indicate statistically significant differences compared to the vector control (*p<0.05; **p < 0.01; ***p < 0.001). In the panels on the right, Vprs were divided into three groups: Vprs from lentiviruses encoding <i>vpu</i> (HIV/SIV_<i>vpu</i>, green), downmodulating CD3 via Nef (HIV/SIV_CD3, blue), or lacking a <i>vpu</i> gene and the CD3-downmodulation activity (SIVolc/col, orange). Whiskers of the boxplots indicate the 5^th and 95^th percentiles.