PPM1A inhibits HIV-1 infection and gene expression. A. HeLa cells were transfected with Flag-PPM1A-WT, Flag-PPM1A-MT, or empty vector expression plasmids. Cell lysates were harvested 48 hours after transfection and probed in an immunoblot for Flag expression and α-Actin. B. Triplicate HeLa cell cultures were transfected with PPM1A-WT, PPM1A-MT, or empty vector expression plasmids. Viability of the transfected cells was measured 48 hours after transfection using the Vi-CELL automatic cell analyzer. C. Triplicate HeLa cell cultures were transfected with PPM1A-WT, PPM1A-MT, or vector expression plasmids; cells were infected with a VSV-G pseudotyped HIV-1 NL4-3 Luciferase reporter virus at 24 hours post-transfection. Luciferase expression was measured in cells extracts at 24 hours post-infection and normalized to total protein in extracts. (* represents p value of < 0.05 in a paired t-test.) D. Triplicate HeLa cell cultures were co-transfected with pNL4-3 Luciferase proviral plasmid plus vector control or expression plasmids for PPM1A-WT or PPM1A-MT. Luciferase expression in cell extracts was measured at 48 hours post-transfection and was normalized to total protein in extracts. (**denotes p value of < 0.005 in a paired t-test.).