Activation of transcription by HIV-1 Tat protein tethered to nascent RNA through another protein
- 1 June 1990
- journal article
- Published by Springer Nature in Nature
- Vol. 345 (6276), 640-642
- https://doi.org/10.1038/345640a0
Abstract
The human immunodeficiency virus type I (HIV-1) nuclear protein Tat is a potent activator of viral gene transcription. Activation by Tat requires a cis-acting element, the transactivation response (TAR) site, located immediately downstream of the transcription start site. Several observations suggest that TAR functions as the nascent RNA product of the HIV long-terminal-repeat promoter (for a review, see ref. 6). Indeed, Tat protein and several cellular proteins bind directly to nascent TAR RNA in vitro. The significance of these in vitro interactions remains to be established. Here we report that Tat can activate transcription when bound to nascent RNA through the RNA-binding domain of another HIV-1 protein, Rev. Rev is a sequence-specific RNA-binding protein, which interacts with the viral RNA element RRE (refs 11-15). A Tat-Rev fusion protein efficiently activates transcription from an HIV-1 promoter derivative, in which TAR has been replaced by the RRE. We conclude that activation of transcription by Tat can occur by direct binding to nascent RNA, and that the sole function of TAR may be to provide a Tat-binding site. Our results further suggest that cellular proteins that bind specifically to TAR RNA or TAR DNA may not be essential for Tat-responsiveness.Keywords
This publication has 32 references indexed in Scilit:
- Identification and characterization of a HeLa nuclear protein that specifically binds to the trans-activation-response (TAR) element of human immunodeficiency virus.Proceedings of the National Academy of Sciences, 1990
- Sequence-specific RNA binding by the HIV-1 Rev proteinNature, 1989
- HIV TAR: An RNA enhancer?Cell, 1989
- Identification of cellular proteins that bind to the human immunodeficiency virus type 1 trans-activation-responsive TAR element RNA.Proceedings of the National Academy of Sciences, 1989
- Human immunodeficiency virus 1 tat protein binds trans-activation-responsive region (TAR) RNA in vitro.Proceedings of the National Academy of Sciences, 1989
- Specific binding of a HeLa cell nuclear protein to RNA sequences in the human immunodeficiency virus transactivating region.Proceedings of the National Academy of Sciences, 1989
- A discrete element 3' of human immunodeficiency virus 1 (HIV-1) and HIV-2 mRNA initiation sites mediates transcriptional activation by an HIV trans activator.Molecular and Cellular Biology, 1988
- Trans -Activator Gene of Human T-Lymphotropic Virus Type III (HTLV-III)Science, 1985
- The location of cis-acting regulatory sequences in the human T cell lymphotropic virus type III (HTLV-III/LAV) long terminal repeatCell, 1985
- A Transcriptional Activator Protein Encoded by the x- lor Region of the Human T-Cell Leukemia VirusScience, 1985