Skip to main content
PMC home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1989 Dec;86(23):9549–9553. doi: 10.1073/pnas.86.23.9549

Nef protein of human immunodeficiency virus type 1: evidence against its role as a transcriptional inhibitor.

S R Hammes 1, E P Dixon 1, M H Malim 1, B R Cullen 1, W C Greene 1
PMCID: PMC298534  PMID: 2687884

Abstract

The type 1 human immunodeficiency virus (HIV-1) encodes a 27-kDa protein termed Nef (negative factor). Nef has been reported to down-regulate viral gene transcription directed by the HIV-1 long terminal repeat. To assess the possible role of Nef in the initiation or maintenance of viral latency, we prepared two different nef expression vectors (pNEF from the HXB-3 proviral clone; pNEF-2/3 from HXB-2 and HXB-3) and a control vector containing a frameshift mutation in the HXB-3 nef coding sequence (pNEF-fs). Consistent with prior studies, the Nef proteins produced by pNEF and pNEF-2/3 were approximately 27 kDa in size, posttranslationally modified by myristoylation, and primarily associated with cytoplasmic membrane structures. However, in contrast to previous reports, these Nef proteins failed to inhibit transcriptional activity of the HIV-1 long terminal repeat in any of a variety of cell types, including primary human T lymphocytes, Jurkat or YT-1 leukemic T cells, U-937 promonocytic cells, and nonlymphoid COS cells. Furthermore, HXB-3 proviral clones of HIV-1 containing either a wild-type or mutated version of the nef gene replicated in an indistinguishable manner when transfected into COS cells. Our findings suggest that Nef is neither a transcriptional inhibitor nor a negative viral factor under these assay conditions. Rather, we suggest that the primary biological function of this conserved HIV-1 protein has yet to be defined, perhaps reflecting an intrinsic shortcoming in the in vitro experimental systems presently available for the study of HIV-1.

Full text

PDF
9553

Images in this article

9550Image
on p.9550
9551Image
on p.9551
9551Image
on p.9551
9552Image
on p.9552

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ahmad N., Venkatesan S. Nef protein of HIV-1 is a transcriptional repressor of HIV-1 LTR. Science. 1988 Sep 16;241(4872):1481–1485. doi: 10.1126/science.3262235. [DOI] [PubMed] [Google Scholar]
  2. Allan J. S., Coligan J. E., Lee T. H., McLane M. F., Kanki P. J., Groopman J. E., Essex M. A new HTLV-III/LAV encoded antigen detected by antibodies from AIDS patients. Science. 1985 Nov 15;230(4727):810–813. doi: 10.1126/science.2997921. [DOI] [PubMed] [Google Scholar]
  3. Berger J., Hauber J., Hauber R., Geiger R., Cullen B. R. Secreted placental alkaline phosphatase: a powerful new quantitative indicator of gene expression in eukaryotic cells. Gene. 1988 Jun 15;66(1):1–10. doi: 10.1016/0378-1119(88)90219-3. [DOI] [PubMed] [Google Scholar]
  4. Cullen B. R. Trans-activation of human immunodeficiency virus occurs via a bimodal mechanism. Cell. 1986 Sep 26;46(7):973–982. doi: 10.1016/0092-8674(86)90696-3. [DOI] [PubMed] [Google Scholar]
  5. Fisher A. G., Ratner L., Mitsuya H., Marselle L. M., Harper M. E., Broder S., Gallo R. C., Wong-Staal F. Infectious mutants of HTLV-III with changes in the 3' region and markedly reduced cytopathic effects. Science. 1986 Aug 8;233(4764):655–659. doi: 10.1126/science.3014663. [DOI] [PubMed] [Google Scholar]
  6. Franchini G., Robert-Guroff M., Ghrayeb J., Chang N. T., Wong-Staal F. Cytoplasmic localization of the HTLV-III 3' orf protein in cultured T cells. Virology. 1986 Dec;155(2):593–599. doi: 10.1016/0042-6822(86)90219-9. [DOI] [PubMed] [Google Scholar]
  7. Guy B., Kieny M. P., Riviere Y., Le Peuch C., Dott K., Girard M., Montagnier L., Lecocq J. P. HIV F/3' orf encodes a phosphorylated GTP-binding protein resembling an oncogene product. Nature. 1987 Nov 19;330(6145):266–269. doi: 10.1038/330266a0. [DOI] [PubMed] [Google Scholar]
  8. Hauber J., Perkins A., Heimer E. P., Cullen B. R. Trans-activation of human immunodeficiency virus gene expression is mediated by nuclear events. Proc Natl Acad Sci U S A. 1987 Sep;84(18):6364–6368. doi: 10.1073/pnas.84.18.6364. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Holbrook N. J., Gulino A., Ruscetti F. Cis-acting transcriptional regulatory sequences in the gibbon ape leukemia virus (GALV) long terminal repeat. Virology. 1987 Mar;157(1):211–219. doi: 10.1016/0042-6822(87)90330-8. [DOI] [PubMed] [Google Scholar]
  10. Kim S., Ikeuchi K., Byrn R., Groopman J., Baltimore D. Lack of a negative influence on viral growth by the nef gene of human immunodeficiency virus type 1. Proc Natl Acad Sci U S A. 1989 Dec;86(23):9544–9548. doi: 10.1073/pnas.86.23.9544. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Lowenthal J. W., Ballard D. W., Böhnlein E., Greene W. C. Tumor necrosis factor alpha induces proteins that bind specifically to kappa B-like enhancer elements and regulate interleukin 2 receptor alpha-chain gene expression in primary human T lymphocytes. Proc Natl Acad Sci U S A. 1989 Apr;86(7):2331–2335. doi: 10.1073/pnas.86.7.2331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Luciw P. A., Cheng-Mayer C., Levy J. A. Mutational analysis of the human immunodeficiency virus: the orf-B region down-regulates virus replication. Proc Natl Acad Sci U S A. 1987 Mar;84(5):1434–1438. doi: 10.1073/pnas.84.5.1434. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Niederman T. M., Thielan B. J., Ratner L. Human immunodeficiency virus type 1 negative factor is a transcriptional silencer. Proc Natl Acad Sci U S A. 1989 Feb;86(4):1128–1132. doi: 10.1073/pnas.86.4.1128. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Olson E. N., Towler D. A., Glaser L. Specificity of fatty acid acylation of cellular proteins. J Biol Chem. 1985 Mar 25;260(6):3784–3790. [PubMed] [Google Scholar]
  15. Ratner L., Haseltine W., Patarca R., Livak K. J., Starcich B., Josephs S. F., Doran E. R., Rafalski J. A., Whitehorn E. A., Baumeister K. Complete nucleotide sequence of the AIDS virus, HTLV-III. Nature. 1985 Jan 24;313(6000):277–284. doi: 10.1038/313277a0. [DOI] [PubMed] [Google Scholar]
  16. Ratner L., Starcich B., Josephs S. F., Hahn B. H., Reddy E. P., Livak K. J., Petteway S. R., Jr, Pearson M. L., Haseltine W. A., Arya S. K. Polymorphism of the 3' open reading frame of the virus associated with the acquired immune deficiency syndrome, human T-lymphotropic virus type III. Nucleic Acids Res. 1985 Nov 25;13(22):8219–8229. doi: 10.1093/nar/13.22.8219. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Sodroski J., Patarca R., Rosen C., Wong-Staal F., Haseltine W. Location of the trans-activating region on the genome of human T-cell lymphotropic virus type III. Science. 1985 Jul 5;229(4708):74–77. doi: 10.1126/science.2990041. [DOI] [PubMed] [Google Scholar]
  18. Terwilliger E., Sodroski J. G., Rosen C. A., Haseltine W. A. Effects of mutations within the 3' orf open reading frame region of human T-cell lymphotropic virus type III (HTLV-III/LAV) on replication and cytopathogenicity. J Virol. 1986 Nov;60(2):754–760. doi: 10.1128/jvi.60.2.754-760.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Wain-Hobson S., Sonigo P., Danos O., Cole S., Alizon M. Nucleotide sequence of the AIDS virus, LAV. Cell. 1985 Jan;40(1):9–17. doi: 10.1016/0092-8674(85)90303-4. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES