JVI Email Content Delivery
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 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 Sinha, S.
Right arrow Articles by Grandgenett, D. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sinha, S.
Right arrow Articles by Grandgenett, D. P.
Journal of Virology, July 2005, p. 8208-8216, Vol. 79, No. 13
0022-538X/05/$08.00+0     doi:10.1128/JVI.79.13.8208-8216.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Recombinant Human Immunodeficiency Virus Type 1 Integrase Exhibits a Capacity for Full-Site Integration In Vitro That Is Comparable to That of Purified Preintegration Complexes from Virus-Infected Cells

Sapna Sinha and Duane P. Grandgenett*

St. Louis University Health Sciences Center, Institute for Molecular Virology, 3681 Park Ave., St. Louis, Missouri 63110

Received 25 October 2004/ Accepted 6 March 2005

Retrovirus preintegration complexes (PIC) in virus-infected cells contain the linear viral DNA genome (~10 kbp), viral proteins including integrase (IN), and cellular proteins. After transport of the PIC into the nucleus, IN catalyzes the concerted insertion of the two viral DNA ends into the host chromosome. This successful insertion process is termed "full-site integration." Reconstitution of nucleoprotein complexes using recombinant human immunodeficiency virus type 1 (HIV-1) IN and model viral DNA donor substrates (~0.30 to 0.48 kbp in length) that are capable of catalyzing efficient full-site integration has proven difficult. Many of the products are half-site integration reactions where either IN inserts only one end of the viral donor substrate into a circular DNA target or into other donors. In this report, we have purified recombinant HIV-1 IN at pH 6.8 in the presence of MgSO4 that performed full-site integration nearly as efficiently as HIV-1 PIC. The size of the viral DNA substrate was significantly increased to 4.1 kbp, thus allowing for the number of viral DNA ends and the concentrations of IN in the reaction mixtures to be decreased by a factor of ~10. In a typical reaction at 37°C, recombinant HIV-1 IN at 5 to 10 nM incorporated 30 to 40% of the input DNA donor into full-site integration products. The synthesis of full-site products continued up to ~2 h, comparable to incubation times used with HIV-1 PIC. Approximately 5% of the input donor was incorporated into the circular target producing half-site products with no significant quantities of other integration products produced. DNA sequence analysis of the viral DNA-target junctions derived from wild-type U3 and U5 coupled reactions showed an ~70% fidelity for the HIV-1 5-bp host site duplications. Recombinant HIV-1 IN successfully utilized a mutant U5 end containing additional nucleotide extensions for full-site integration demonstrating that IN worked properly under nonideal active substrate conditions. The fidelity of the 5-bp host site duplications was also high with these coupled mutant U5 and wild-type U3 donor ends. These studies suggest that recombinant HIV-1 IN is at least as capable as native IN in virus particles and approaching that observed with HIV-1 PIC for catalyzing full-site integration.


* Corresponding author. Mailing address: St. Louis University Health Sciences Center, Institute for Molecular Virology, 3681 Park Ave., St. Louis, MO 63110. Phone: (314) 977-8784. Fax: (314) 977-8798. E-mail: Grandgdp{at}slu.edu.


Journal of Virology, July 2005, p. 8208-8216, Vol. 79, No. 13
0022-538X/05/$08.00+0     doi:10.1128/JVI.79.13.8208-8216.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Mol. Cell. Biol. Microbiol. Mol. Biol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 2005 by the American Society for Microbiology. All rights reserved.