AEGiS-05CROI: The putative alpha helix 2 of HIV-1 Vpr contains a determinant which is responsible for the translocation of the proviral DNA in growth-arrested cells.

5th Conference on Retroviruses and Opportunistic Infections

Chicago, IL - February 1-5, 1998

The putative alpha helix 2 of HIV-1 Vpr contains a determinant which is responsible for the translocation of the proviral DNA in growth-arrested cells.

Conf Retroviruses Opportunistic Infect 1998 Feb 1-5; 5th:84 (abstract no. 27)

Cohen EA, Subbramanian RA, Nie Z, Yao XJ, Rougeau N, Bergeron D; Universite de Montreal, Quebec, Canada.

Several viral determinants were shown to play a role in the ability of HIV to infect nondividing cells. In particular, Vpr and Gag matrix (MA) were recognized to be involved in the nuclear transport of the viral preintegration complex (PIC). The goal of the present study was to evaluate the ability of isogenic HIV-1 viruses harboring different vpr and gag genes to infect nondividing cells. Surprisingly, our results reveal that the introduction of mutations in the MA nuclear localization signal affected marginally the ability of proviruses to establish infection in growth-arrested HeLa or MT4 cells. In contrast and in agreement with previous reports, we show that in our experimental system the absence of Vpr expression leads to a reduction in viral infectivity and production which correlates with a decrease in the nuclear transport of proviral DNA as determined by PCR analysis. Moreover, our data demonstrate that this reduction of viral replication is also observed with proviruses containing different mutated Vpr alleles. In particular, the Vpr-Q65E mutant, which contains a substitution in the predicted amphipatic alpha helical structure located in the central region of the protein, is associated with a reduction of the nuclear transport of proviral DNA. Moreover, using confocal microscopy, we also show that mutations in this putative central hydrophobic helix of Vpr result in the retention of the protein in highly localized ring-like structures around the nuclear periphery with striking impairment in their ability to enter the nuclear interior. Overall, these results identify a putative amphipatic helical alpha structure in the central region of Vpr as the domain involve in the nuclear transport of the preintegration complex in nondividing cells.

Keywords: AEGIS, HIV-1, Virus Replication, DNA, Proviruses, Nuclear Localization Signal, Cell Nucleus, Translocation (Genetics), Mutation, DNA Primers, Genes, gag, Active Transport, Cell Nucleus, virology, genetics, AIDS

1998-02-01
27

Copyright © 1998 - Foundation for Retrovirology and Human Health (IAS). Reproduction of this abstract (other than one copy for personal reference) must be cleared through the Foundation for Retrovirology and Human Health. Licensed from National Library of Medicine.