This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Pettit, S. C.
Right arrow Articles by Kaplan, A. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Pettit, S. C.
Right arrow Articles by Kaplan, A. H.

 Previous Article  |  Next Article 

Journal of Virology, August 2004, p. 8477-8485, Vol. 78, No. 16
0022-538X/04/$08.00+0     DOI: 10.1128/JVI.78.16.8477-8485.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Initial Cleavage of the Human Immunodeficiency Virus Type 1 GagPol Precursor by Its Activated Protease Occurs by an Intramolecular Mechanism

Steven C. Pettit,1 Lorraine E. Everitt,1 Sumana Choudhury,1 Ben M. Dunn,2 and Andrew H. Kaplan1,3,4,5*

Departments of Medicine,1 Microbiology and Immunology,3 the Lineberger Comprehensive Cancer Center,4 the Center for Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7290,5 Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, Florida 32610-02452

Received 3 December 2003/ Accepted 12 April 2004

Processing of the GagPol polyprotein precursor of human immunodeficiency virus type 1 (HIV-1) is a critical step in viral assembly and replication. The HIV-1 protease (PR) is translated as part of GagPol and is both necessary and sufficient for precursor processing. The PR is active only as a dimer; enzyme activation is initiated when the PR domains in two GagPol precursors dimerize. The precise mechanism by which the PR becomes activated and the subsequent initial steps in precursor processing are not well understood. However, it is clear that processing is initiated by the PR domain that is embedded within the precursor itself. We have examined the earliest events in precursor processing using an in vitro assay in which full-length GagPol is cleaved by its embedded PR. We demonstrate that the embedded, immature PR is as much as 10,000-fold less sensitive to inhibition by an active-site PR inhibitor than is the mature, free enzyme. Further, we find that different concentrations of the active-site inhibitor are required to inhibit the processing of different cleavage sites within GagPol. Finally, our results indicate that the first cleavages carried out by the activated PR within GagPol are intramolecular. Overall, our data support a model of virus assembly in which the first cleavages occur in GagPol upstream of the PR. These intramolecular cleavages produce an extended form of PR that completes the final processing steps accompanying the final stages of particle assembly by an intermolecular mechanism.

* Corresponding author. Mailing address: 705 MEJ/CB#7290, UNC-Chapel Hill, Chapel Hill, NC 27599-7290. Phone: (919) 843-0693. Fax: (919) 962-8103. E-mail: akaplan{at}med.unc.edu.

Journal of Virology, August 2004, p. 8477-8485, Vol. 78, No. 16
0022-538X/04/$08.00+0     DOI: 10.1128/JVI.78.16.8477-8485.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Muller, B., Anders, M., Akiyama, H., Welsch, S., Glass, B., Nikovics, K., Clavel, F., Tervo, H.-M., Keppler, O. T., Krausslich, H.-G. (2009). HIV-1 Gag Processing Intermediates Trans-dominantly Interfere with HIV-1 Infectivity. J. Biol. Chem. 284: 29692-29703 [Abstract] [Full Text]  
  • Leiherer, A., Ludwig, C., Wagner, R. (2009). Uncoupling Human Immunodeficiency Virus Type 1 gag and pol Reading Frames: Role of the Transframe Protein p6* in Viral Replication. J. Virol. 83: 7210-7220 [Abstract] [Full Text]  
  • Ludwig, C., Leiherer, A., Wagner, R. (2008). Importance of Protease Cleavage Sites within and Flanking Human Immunodeficiency Virus Type 1 Transframe Protein p6* for Spatiotemporal Regulation of Protease Activation. J. Virol. 82: 4573-4584 [Abstract] [Full Text]  
  • Villena, C., Prado, J. G., Puertas, M. C., Martinez, M. A., Clotet, B., Ruiz, L., Parkin, N. T., Menendez-Arias, L., Martinez-Picado, J. (2007). Relative Fitness and Replication Capacity of a Multinucleoside Analogue-Resistant Clinical Human Immunodeficiency Virus Type 1 Isolate with a Deletion of Codon 69 in the Reverse Transcriptase Coding Region. J. Virol. 81: 4713-4721 [Abstract] [Full Text]  
  • Abram, M. E., Parniak, M. A. (2005). Virion Instability of Human Immunodeficiency Virus Type 1 Reverse Transcriptase (RT) Mutated in the Protease Cleavage Site between RT p51 and the RT RNase H Domain. J. Virol. 79: 11952-11961 [Abstract] [Full Text]  
  • Wapling, J., Moore, K. L., Sonza, S., Mak, J., Tachedjian, G. (2005). Mutations That Abrogate Human Immunodeficiency Virus Type 1 Reverse Transcriptase Dimerization Affect Maturation of the Reverse Transcriptase Heterodimer. J. Virol. 79: 10247-10257 [Abstract] [Full Text]  
  • Pettit, S. C., Clemente, J. C., Jeung, J. A., Dunn, B. M., Kaplan, A. H. (2005). Ordered Processing of the Human Immunodeficiency Virus Type 1 GagPol Precursor Is Influenced by the Context of the Embedded Viral Protease. J. Virol. 79: 10601-10607 [Abstract] [Full Text]  
  • Guo, F., Gabor, J., Cen, S., Hu, K., Mouland, A. J., Kleiman, L. (2005). Inhibition of Cellular HIV-1 Protease Activity by Lysyl-tRNA Synthetase. J. Biol. Chem. 280: 26018-26023 [Abstract] [Full Text]  
  • Chatterjee, A., Mridula, P., Mishra, R. K., Mittal, R., Hosur, R. V. (2005). Folding Regulates Autoprocessing of HIV-1 Protease Precursor. J. Biol. Chem. 280: 11369-11378 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»