Fig. 7: HIV-1 infection promotes the VOR complex formation in a microtubule-dependent manner.

a PHA/IL-2-activated CD4⁺ T cells were noninfected (control) or 6-h HIV-89.6-EGFP infected after 30-min pretreatment with DMSO or 10 µM PRR851. The drug was present during infection. Cells were then solubilized and subjected to ORP3 IS. The bound fractions and the input (1/50) were probed for ORP3, VAP-A, and Rab7 by IB. b Cells were 5-min pretreated with DMSO or nocodazole (1 µM) and then noninfected (control) or 1-h HIV-89.6-EGFP infected, solubilized and processed for ORP3 IS and ORP3, VAP-A and Rab7 IB. All samples came from the same experiment and were run in parallel (a, b). Molecular mass markers (kDa) are indicated. Representative experiments are shown. We used a MOI of 2. Note that VOR complex formation only occurs after HIV-1 infection and is hindered by PRR851 and nocodazole. c Representation of the induction of type II NEIs by virus-laden late endosomes, a process mediated by the interaction of VOR complex proteins, namely ONM-associated VAP-A, cytoplasmic ORP3, and late endosome-associated Rab7 (left panel). Release of viral components from late endosomes into the cytoplasmic core of induced NEIs at the vicinity of the nuclear pore would facilitate their transfer to the nucleoplasm (right panel). PRR851 inhibits the interaction of the VOR complex proteins, and hence the NEI formation. ILV, intralumenal vesicles associated with late endosome/multivesicular body; INM/ONM, inner/outer nuclear membrane; MTOC, microtubule-organizing center; MTs, microtubules.