Defective Replication in Human Immunodeficiency Virus Type 1 When Non-\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{tRNA}_{3}^{\mathrm{Lys}}\) \end{document}Primers Are Used for Reverse Transcription

ABSTRACT \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} , the primer for reverse transcriptase in human immunodeficiency virus type 1 (HIV-1), anneals to the primer binding site (PBS) in HIV-1 RNA. It has been shown that altering the PBS and U5 regions upstream of the PBS in HIV-1 so as to be complementary to sequences in tRNAMet or tRNAHis will allow these tRNA species to be stably used as primers for reverse transcription. We have examined the replication of these mutant viruses in Sup-T1 cells. When Sup-T1 cells are infected by cocultivation with HIV-1-transfected 293T cells, viruses using tRNAHis or tRNAMet are produced at rates that are approximately 1/10 or 1/100, respectively, of rates for wild-type virions that use \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} . When Sup-T1 cells are directly infected with equal amounts of these different viruses isolated from the culture supernatant of transfected 293T cells, virions using tRNAMet are produced at 1/100 the rate of wild-type viruses, and production of virions using tRNAHis is not detected. Both wild-type and mutant virions selectively package tRNALys only, and examination of the ability of total viral RNA to prime reverse transcription in vitro indicates a >80% reduction in the annealing of tRNAHis or tRNAMet to the mutant viral RNAs. PCR analysis of which of the three primer tRNAs is used indicates that only \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} is detected as primer in wild-type virions and only tRNAHis is detected as primer in virions containing a PBS complementary to tRNAHis, while the mutant viruses containing a PBS complementary to tRNAMet use both tRNAMet and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{1,2}^{Lys}\) \end{document} as primer tRNAs.

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Inability of Human Immunodeficiency Virus Type 1 Produced in Murine Cells To Selectively Incorporate Primer \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{tRNA}_{3}^{\mathrm{Lys}}\) \end{document}

Journal of Virology ◽

10.1128/jvi.01744-08 ◽

2008 ◽

Vol 82 (24) ◽

pp. 12049-12059 ◽

Cited By ~ 4

Author(s):

Min Wei ◽

Yiliang Yang ◽

Meijuan Niu ◽

Laurie Desfosse ◽

Robert Kennedy ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Leukemia Virus ◽

Trna Synthetase ◽

Primer Binding Site ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Attempts to use the mouse as a model system for studying AIDS are stymied by the multiple blocks to human immunodeficiency virus type 1 (HIV-1) replication that exist in mouse cells at the levels of viral entry, transcription, and Gag assembly and processing. In this report, we describe an additional block in the selective packaging of \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} into HIV-1 produced in murine cells. HIV-1 and murine leukemia virus (MuLV) use \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} and tRNAPro, respectively, as primers for reverse transcription. Selective packaging of \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} into HIV-1 produced in human cells is much stronger than that for tRNAPro incorporation into MuLV produced in murine cells, and different packaging mechanisms are used. Thus, both lysyl-tRNA synthetase and GagPol are required for \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} packaging into HIV-1, but neither prolyl-tRNA synthetase nor GagPol is required for tRNAPro packaging into MuLV. In this report, we show that when HIV-1 is produced in murine cells, the virus switches from an HIV-1-like incorporation of \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} to an MuLV-like packaging of tRNAPro. The primer binding site in viral RNA remains complementary to \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} , resulting in a significant decrease in reverse transcription and infectivity. Reduction in \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} incorporation occurs even though both murine lysyl-tRNA synthetase and HIV-1 GagPol are packaged into the HIV-1 produced in murine cells. Nevertheless, the murine cell is able to support the select incorporation of \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} into another retrovirus that uses \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} as a primer, the mouse mammary tumor virus.

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Probing the Importance of tRNA Anticodon: Human Immunodeficiency Virus Type 1 (HIV-1) RNA Genome Complementarity with an HIV-1 That Selects tRNAGlu for Replication

Journal of Virology ◽

10.1128/jvi.77.16.8756-8764.2003 ◽

2003 ◽

Vol 77 (16) ◽

pp. 8756-8764 ◽

Cited By ~ 18

Author(s):

Lesley C. Dupuy ◽

Nathan J. Kelly ◽

Tricia E. Elgavish ◽

Stephen C. Harvey ◽

Casey D. Morrow

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Mononuclear Cells ◽

Primer Binding Site ◽

Wild Type Virus ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT The initiation of human immunodeficiency virus type 1 (HIV-1) reverse transcription occurs at the primer binding site (PBS) that is complementary to the 3′-terminal nucleotides of tRNA3 Lys. Why all known strains of HIV-1 select tRNA3 Lys for replication is unknown. Previous studies on the effect of altering the PBS of HIV-1 on replication identified an HIV-1 with a PBS complementary to tRNAGlu. Since the virus was not initially designed to use tRNAGlu, the virus had selected tRNAGlu from the intracellular pool of tRNA for use in replication. Further characterization of HIV-1 that uses tRNAGlu may provide new insights into the preference for tRNA3 Lys. HIV-1 constructed with the PBS complementary to tRNAGlu was more stable than HIV-1 with the PBS complementary to tRNAMet or tRNAHis; however, all of these viruses eventually reverted back to using tRNA3 Lys following growth in SupT1 cells or peripheral blood mononuclear cells (PBMCs). New HIV-1 mutants with nucleotides in U5 complementary to the anticodon of tRNAGlu remained stable when grown in SupT1 cells or PBMCs, although the mutants grew more slowly than the wild-type virus. Sequence analysis of the U5 region and the PBS revealed additional mutations predicted to further promote tRNA-viral genome interaction. The results support the importance of the tRNA anticodon-genome interaction in the selection of the tRNA primer and highlight the fact that unique features of tRNA3 Lys are exploited by HIV-1 for selection as the reverse transcription primer.

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Preferential Completion of Human Immunodeficiency Virus Type 1 Proviruses Initiated with tRNA3Lys rather than tRNA1,2Lys

Journal of Virology ◽

10.1128/jvi.72.7.5464-5471.1998 ◽

1998 ◽

Vol 72 (7) ◽

pp. 5464-5471 ◽

Cited By ~ 7

Author(s):

Zhijun Zhang ◽

Qin Yu ◽

Sang-Moo Kang ◽

James Buescher ◽

Casey D. Morrow

Keyword(s):

Human Immunodeficiency Virus ◽

Single Cell ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Primer Binding Site ◽

Proviral Dna ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT All retroviral genomes contain a nucleotide sequence designated as the primer binding site (PBS) which is complementary to the tRNA used for initiation of reverse transcription. For human immunodeficiency virus type 1 (HIV-1), all naturally occurring genomes have a PBS complementary to tRNA3 Lys. However, within HIV-1 virions, there are approximately equal amounts of tRNA1 Lys, tRNA2 Lys, and tRNA3 Lys. We have used an endogenous reverse transcription-PCR technique specific for the tRNA species within isolated HIV-1 virions to demonstrate that in addition to tRNA3 Lys, tRNA1 Lys and tRNA2 Lys could be used for initiation of HIV-1 reverse transcription. Using a single-round infection assay which employed an HIV-1 genome with a gpt gene encoding xanthine-guanine phosphoribosyl transferase in place of the env gene, we generated cell lines resistant to mycophenolic acid. Analysis of the U5-PBS from single-cell clones revealed PBS complementary to tRNA3 Lys, not tRNA1 Lys or tRNA2 Lys. A mutant HIV-1 genome was then created which would favor the completion of reverse transcription with tRNA1,2 Lys. Using this provirus in the complementation system, we again found only genomes with a PBS complementary to tRNA3 Lys from proviral DNA isolated fromgpt-resistant single-cell colonies. Finally, infection of cells with a mutant HIV genome with a PBS complementary to tRNA1,2 Lys resulted in gpt- resistant cell colonies which contained integrated provirions with a PBS complementary to tRNA1,2 Lys. The results of these studies suggest that the selection of tRNA3 Lys for initiation of HIV-1 reverse transcription occurs both at the initiation and at a postinitiation step in reverse transcription prior to integration of the proviral DNA.

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Mutational Analysis of the C-Terminal Gag Cleavage Sites in Human Immunodeficiency Virus Type 1

Journal of Virology ◽

10.1128/jvi.02496-06 ◽

2007 ◽

Vol 81 (18) ◽

pp. 10047-10054 ◽

Cited By ~ 46

Author(s):

Lori V. Coren ◽

James A. Thomas ◽

Elena Chertova ◽

Raymond C. Sowder ◽

Tracy D. Gagliardi ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Mutational Analysis ◽

Cleavage Sites ◽

Wild Type ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) Gag is expressed as a polyprotein that is cleaved into six proteins by the viral protease in a maturation process that begins during assembly and budding. While processing of the N terminus of Gag is strictly required for virion maturation and infectivity, the necessity for the C-terminal cleavages of Gag is less well defined. To examine the importance of this process, we introduced a series of mutations into the C terminus of Gag that interrupted the cleavage sites that normally produce in the nucleocapsid (NC), spacer 2 (SP2), or p6Gag proteins. Protein analysis showed that all of the mutant constructs produced virions efficiently upon transfection of cells and appropriately processed Gag polyprotein at the nonmutated sites. Mutants that produced a p9NC/SP2 protein exhibited only minor effects on HIV-1 infectivity and replication. In contrast, mutants that produced only the p8SP2/p6 or p15NC/SP2/p6 protein had severe defects in infectivity and replication. To identify the key defective step, we quantified reverse transcription and integration products isolated from infected cells by PCR. All mutants tested produced levels of reverse transcription products either similar to or only somewhat lower than that of wild type. In contrast, mutants that failed to cleave the SP2-p6Gag site produced drastically less provirus than the wild type. Together, our results show that processing of the SP2-p6Gag and not the NC-SP2 cleavage site is important for efficient viral DNA integration during infection in vitro. In turn, this finding suggests an important role for the p9NC/SP2 species in some aspect of integration.

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The Role of Nucleocapsid and U5 Stem/A-Rich Loop Sequences in tRNA3Lys Genomic Placement and Initiation of Reverse Transcription in Human Immunodeficiency Virus Type 1

Journal of Virology ◽

10.1128/jvi.72.5.3907-3915.1998 ◽

1998 ◽

Vol 72 (5) ◽

pp. 3907-3915 ◽

Cited By ~ 35

Author(s):

Yue Huang ◽

Ahmad Khorchid ◽

Juliana Gabor ◽

Jing Wang ◽

Xuguang Li ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Wild Type ◽

Extracellular Virus ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT We have studied the effect of mutations in the human immunodeficiency virus type 1 (HIV-1) nucleocapsid (NC) sequence on tRNA3 Lys genomic placement, i.e., the in vivo placement of primer tRNA3 Lys on the HIV-1 primer binding site (PBS). HIV-1 produced from COS cells transfected with wild-type or mutant proviral DNA was used in this study. We have found that mutations in the amino acid sequences flanking the first Cys-His box in the NC sequence produce the maximum inhibition of genomic placement. A similar finding was obtained when the NC-facilitated annealing of primer tRNA3 Lys to the HIV PBS in vitro was studied. However, since the genomic placement of tRNA3 Lys occurs independently of precursor protein processing, the NC mutations studied here have probably exerted their effect through one or both of the precursor proteins, Pr55 gag and/or Pr160 gag-pol . One mutation in the linker region between the two Cys-His boxes, P31L, prevented packaging of both Pr160 gag-pol and tRNA3 Lys and prevented the genomic placement of tRNA3 Lys. Both packaging and genomic placement were rescued by cotransfection with a plasmid coding for wild-type Pr160 gag-pol . For other linker mutations [R7R10K11 S, R32G, and S3(32-34)], packaging of Pr160 gag-pol and tRNA3 Lyswas not affected, but genomic placement was, and placement could not be rescued by cotransfection with plasmids coding for either Pr55 gag or Pr160 gag-pol . After placement, the initiation of reverse transcription within extracellular virions is characterized by a 2-base DNA extension of the placed tRNA3 Lys. This process requires precursor processing, and those NC mutations which showed the most inhibition of initiation were in either of the two NC Cys-His boxes. Destabilization of a U5 stem-A-rich loop immediately upstream of the PBS (through deletion of four consecutive A’s in the loop) did not affect the in vivo genomic placement of tRNA3 Lys but resulted in the presence in the extracellular virus of longer cDNA extensions of tRNA3 Lys, with a corresponding decrease in the presence of unextended and 2-base-extended tRNA3 Lys.

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Restoration of Wild-Type Infectivity to Human Immunodeficiency Virus Type 1 Strains Lacking nef by Intravirion Reverse Transcription

Journal of Virology ◽

10.1128/jvi.75.24.12081-12087.2001 ◽

2001 ◽

Vol 75 (24) ◽

pp. 12081-12087 ◽

Cited By ~ 27

Author(s):

Mahfuz Khan ◽

Minerva Garcia-Barrio ◽

Michael D. Powell

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Envelope Protein ◽

Wild Type ◽

Virus Envelope ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) Nef protein exerts several effects, both on infected cells and as a virion protein, which work together to enhance viral replication. One of these activities is the ability to enhance infectivity and the formation of proviral DNA. The mechanism of this enhancement remains incompletely understood. We show that virions with nef deleted can be restored to wild-type infectivity by stimulating intravirion reverse transcription. Particle composition and measures of reverse transcriptase activity remain the same for Nef+ and Nef− virions both before and after natural endogenous reverse transcription (NERT) treatment. The effect of NERT treatment on virions pseudotyped with murine leukemia virus envelope protein was similar to that on particles pseudotyped with HIV-1 envelope protein. However, virions pseudotyped with vesicular stomatitis virus G envelope protein showed no influence of Nef on NERT enhancement of infectivity. These observations suggest that Nef may function at a level prior to reverse transcription. Since NERT treatment results in partial disassembly of the viral core, we speculate that Nef may function at the level of core particle disassembly.

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Requirement for Integrase during Reverse Transcription of Human Immunodeficiency Virus Type 1 and the Effect of Cysteine Mutations of Integrase on Its Interactions with Reverse Transcriptase

Journal of Virology ◽

10.1128/jvi.78.10.5045-5055.2004 ◽

2004 ◽

Vol 78 (10) ◽

pp. 5045-5055 ◽

Cited By ~ 113

Author(s):

Kai Zhu ◽

Charles Dobard ◽

Samson A. Chow

Keyword(s):

Human Immunodeficiency Virus ◽

Life Cycle ◽

Reverse Transcriptase ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Wild Type ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Retroviral integrase catalyzes the essential step of integrating a double-stranded DNA copy of the viral genome into a host cell chromosome. Mutational studies have revealed that integrase is involved in additional steps of viral replication, but the mechanism for the pleiotropic effect is not well characterized. Since Cys residues generally play crucial roles in protein structure and function, we introduced Cys-to-Ser substitutions at positions 56, 65, and 130 of human immunodeficiency virus type 1 (HIV-1) integrase to determine their effects on integration activity and viral replication. None of the substitutions significantly affected the enzymatic activities in vitro. When introduced into the NL4-3 molecular clone of HIV-1, mutant viruses encoding Cys mutations at positions 56 and 65 of integrase replicated similarly to the wild-type virus in CD4+-T-cell lines, whereas the C130S-containing virus was noninfectious. The entry and postintegration steps of the viral life cycle for all mutant viruses were normal, and all had particle-associated reverse transcriptase (RT) activity. However, early reverse-transcribed DNA products were absent in the lysate of cells infected with the C130S mutant virus, indicating that the mutation abolished the ability of the virus to initiate endogenous reverse transcription. Coimmunoprecipitation using purified integrase and RT showed that the C-terminal domain of wild-type HIV-1 integrase interacted with RT. The interaction between integrase and RT was not affected in the presence of a reducing or alkylating agent, suggesting that the interaction did not involve a disulfide linkage. The C130S substitution within the core region may disrupt the protein recognition interface of the C-terminal domain and abolish its ability to interact with RT. Our results indicate that integrase plays an important role during the reverse-transcription step of the viral life cycle, possibly through physical interactions with RT.

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Mutations in Human Immunodeficiency Virus Type 1 Nucleocapsid Protein Zinc Fingers Cause Premature Reverse Transcription

Journal of Virology ◽

10.1128/jvi.00583-08 ◽

2008 ◽

Vol 82 (19) ◽

pp. 9318-9328 ◽

Cited By ~ 32

Author(s):

James A. Thomas ◽

William J. Bosche ◽

Teresa L. Shatzer ◽

Donald G. Johnson ◽

Robert J. Gorelick

Keyword(s):

Human Immunodeficiency Virus ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Nucleocapsid Protein ◽

Productive Infection ◽

Wild Type ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) requires that its genome be reverse transcribed into double-stranded DNA for productive infection of cells. This process requires not only reverse transcriptase but also the nucleocapsid protein (NC), which functions as a nucleic acid chaperone. Reverse transcription generally begins once the core of the virion enters the cytoplasm of a newly infected cell. However, some groups have reported the presence of low levels of viral DNA (vDNA) within particles prior to infection, the significance and function of which is controversial. We report here that several HIV-1 NC mutants, which we previously identified as being replication defective, contain abnormally high levels of intravirion DNA. These findings were further reinforced by the inability of these NC mutants to perform endogenous reverse transcription (ERT), in contrast to the readily measurable ERT activity in wild-type HIV-1. When either of the NC mutations is combined with a mutation that inactivates the viral protease, we observed a significant reduction in the amount of intravirion DNA. Interestingly, we also observed high levels of intravirion DNA in the context of wild-type NC when we delayed budding by means of a PTAP(−) (Pro-Thr-Ala-Pro) mutation. Premature reverse transcription is most probably occurring before these mutant virions bud from producer cells, but we fail to see any evidence that the NC mutations alter the timing of Pr55Gag processing. Critically, our results also suggest that the presence of intravirion vDNA could serve as a diagnostic for identifying replication-defective HIV-1.

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Functional Domains of Tat Required for Efficient Human Immunodeficiency Virus Type 1 Reverse Transcription

Journal of Virology ◽

10.1128/jvi.73.3.2499-2508.1999 ◽

1999 ◽

Vol 73 (3) ◽

pp. 2499-2508 ◽

Cited By ~ 27

Author(s):

Catherine Ulich ◽

Amanda Dunne ◽

Emma Parry ◽

C. William Hooker ◽

Richard B. Gaynor ◽

...

Keyword(s):

Gene Expression ◽

Human Immunodeficiency Virus ◽

Cell Lines ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Wild Type ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Tat expression is required for efficient human immunodeficiency virus type 1 (HIV-1) reverse transcription. In the present study, we generated a series of 293 cell lines that contained a provirus with atat gene deletion (Δtat). Cell lines that contained Δtat and stably transfected vectors containing either wild-type tat or a number of tat mutants were obtained so that the abilities of these tat genes to stimulate HIV-1 gene expression and reverse transcription could be compared. tat genes with mutations in the amino terminus did not stimulate either viral gene expression or HIV-1 reverse transcription. In contrast, tat mutants in the activation, core, and basic domains of Tat did not stimulate HIV-1 gene expression but markedly stimulated HIV-1 reverse transcription. No differences in the levels of virion genomic RNA or tRNA3 Lys were seen in the HIV-1 Δtat viruses complemented with either mutant or wild-type tat. Finally, overexpression of the Tat-associated kinases CDK7 and CDK9, which are involved in Tat activation of HIV-1 transcription, was not able to complement the reverse transcription defects associated with the lack of a functionaltat gene. These results indicate that the mechanism by which tat modulates HIV-1 reverse transcription is distinct from its ability to activate HIV-1 gene expression.

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Alternative tRNA Priming of Human Immunodeficiency Virus Type 1 Reverse Transcription Explains Sequence Variation in the Primer-Binding Site That Has Been Attributed to APOBEC3G Activity

Journal of Virology ◽

10.1128/jvi.79.5.3179-3181.2005 ◽

2005 ◽

Vol 79 (5) ◽

pp. 3179-3181 ◽

Cited By ~ 11

Author(s):

Atze T. Das ◽

Monique Vink ◽

Ben Berkhout

Keyword(s):

Human Immunodeficiency Virus ◽

Binding Site ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Reverse Transcription ◽

Sequence Variation ◽

Primer Binding Site ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT It is generally assumed that human immunodeficiency virus type 1 (HIV-1) uses exclusively the cellular \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} molecule as a primer for reverse transcription. We demonstrate that HIV-1 uses not only \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{3}^{Lys}\) \end{document} but also an alternative tRNA primer. This tRNA was termed \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{5}^{Lys}\) \end{document} , and the near completion of the human genome project has allowed the identification of four \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{5}^{Lys}\) \end{document} encoding genes. Priming with \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{5}^{Lys}\) \end{document} results in a single nucleotide polymorphism in the viral primer-binding site that is present in multiple natural and laboratory HIV isolates. This sequence variation was recently attributed to APOBEC3G activity. However, our results show that alternative tRNA priming can cause this mutation in the absence of APOBEC3G.

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