HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 281, Issue 19, 13388-13395, May 12, 2006

This Article Full Text Full Text (PDF) All Versions of this Article: 281/19/13388    most recent M600291200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jamburuthugoda, V. K. Articles by Kim, B. Search for Related Content PubMed PubMed Citation Articles by Jamburuthugoda, V. K. Articles by Kim, B. Social Bookmarking                      What's this?

Modification of Human Immunodeficiency Virus Type 1 Reverse Transcriptase to Target Cells with Elevated Cellular dNTP Concentrations^*

Varuni K. Jamburuthugoda¹, Pauline Chugh¹, and Baek Kim²

From the Department of Microbiology and Immunology and the Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York 14642

Retroviruses and DNA viruses utilize cellular dNTPs as substrates for their DNA polymerases during viral replication in infected cells. However, because of S phase-dependent dNTP biosynthesis, the availability of cellular dNTPs significantly varies among cell types (e.g. dividing versus nondividing cells and normal versus tumor cells). Here we tested whether alterations in the dNTP utilization efficiency and dNTP binding affinity of viral DNA polymerases can switch viral infection specificity to cell types with different dNTP concentrations. We employed an HIV-1 reverse transcriptase (RT) mutant (Q151N), which is catalytically active only at high dNTP concentrations because of its reduced dNTP binding affinity. Indeed, the modified HIV-1 vector harboring the Q151N mutant RT preferentially transduced tumor cells containing higher cellular dNTP concentrations than primary cells (e.g. human lung fibroblasts (HLFs) and human keratinocytes). Although the wild type HIV-1 vector transduced both HLFs and tumor cells, the Q151N vector failed to transduce HLFs and keratinocytes but efficiently transduced tumor cells. Pretreatment of HLFs with deoxynucleosides, which increase cellular dNTP pools, enabled the mutant vector to transduce HLFs, suggesting that the transduction failure of the RT mutant vector to primary cells is because of inefficient reverse transcription in low cellular dNTP environments. We also observed that the Q151N vector expressing herpes simplex virus-thymidine kinase renders tumor cells sensitive to gancyclovir. This study validates a novel strategy in which modifications of viral DNA polymerases in various vector systems allow the delivery of target genes exclusively to tumor cells exploiting elevated cellular dNTP concentration as a tumor cell-specific host factor.

Received for publication, January 11, 2006 , and in revised form, February 8, 2006.

^* This work was supported by National Institutes of Health Research Grant AI49781 (to B. K.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ Both authors equally contributed to this work.

² To whom correspondence should be addressed: Dept. of Microbiology and Immunology, University of Rochester Medical Center, 601 Elmwood Ave., Box 672, Rochester, NY 14642. Tel.: 585-275-6916; Fax: 585-473-9573; E-mail: baek_kim{at}urmc.rochester.edu.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				J. Santos-Velazquez and B. Kim Deoxynucleoside Triphosphate Incorporation Mechanism of Foamy Virus (FV) Reverse Transcriptase: Implications for Cell Tropism of FV J. Virol., August 15, 2008; 82(16): 8235 - 8238. [Abstract] [Full Text] [PDF]

				M. Skasko and B. Kim Compensatory Role of Human Immunodeficiency Virus Central Polypurine Tract Sequence in Kinetically Disrupted Reverse Transcription J. Virol., August 1, 2008; 82(15): 7716 - 7720. [Abstract] [Full Text] [PDF]

				V. K Jamburuthugoda, J. M. Santos-Velazquez, M. Skasko, D. J. Operario, V. Purohit, P. Chugh, E. A. Szymanski, J. E. Wedekind, R. A. Bambara, and B. Kim Reduced dNTP Binding Affinity of 3TC-resistant M184I HIV-1 Reverse Transcriptase Variants Responsible for Viral Infection Failure in Macrophage J. Biol. Chem., April 4, 2008; 283(14): 9206 - 9216. [Abstract] [Full Text] [PDF]

				D. J. Operario, M. Balakrishnan, R. A. Bambara, and B. Kim Reduced dNTP Interaction of Human Immunodeficiency Virus Type 1 Reverse Transcriptase Promotes Strand Transfer J. Biol. Chem., October 27, 2006; 281(43): 32113 - 32121. [Abstract] [Full Text] [PDF]