Colocalization and interaction of hVIP/MOV34 with HIV-1 Vpr mutants. (a) Mutant Vpr molecules were generated by overlap PCR as described (17, 28). HeLa cells were cotransfected with hVIP/MOV34 and various Vpr mutants (A30L, αL-A, A59P, L67S, H71C, G75A, and C76S). The transfected cells were fixed and stained as described above and visualized with fluorescence and rhodamine wavelength filters to detect expression, and the cell cycle arrest activity of Vpr mutants was determined by flow cytometric analysis. (b) Subcellular distribution of hVIP/MOV34 in various Vpr mutants was assayed by indirect immunofluorescence.