Compensatory Role of Human Immunodeficiency Virus Central Polypurine Tract Sequence in Kinetically Disrupted Reverse Transcription

ABSTRACT We tested whether the additional positive-strand DNA synthesis initiation of human immunodeficiency virus type 1 (HIV-1) from the central polypurine tract (cPPT) facilitates efficient completion of kinetically disturbed proviral DNA synthesis induced by dysfunctional reverse transcriptase (RT) mutants or limited cellular deoxynucleoside triphosphate (dNTP) pools. Indeed, the cPPT enabled the HIV-1 vectors harboring RT mutants with reduced dNTP binding affinity to transduce human lung fibroblasts (HLFs), without which these mutant vectors normally fail to transduce. The cPPT showed little effect on wild-type HIV-1 vector transduction in HLF, whereas it significantly enhanced vector transduction in HLFs engineered to contain reduced dNTP pools, suggesting a novel compensatory role for cPPT in viruses harboring kinetically impaired RT.

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Role of Vif in Stability of the Human Immunodeficiency Virus Type 1 Core

Journal of Virology ◽

10.1128/jvi.74.23.11055-11066.2000 ◽

2000 ◽

Vol 74 (23) ◽

pp. 11055-11066 ◽

Cited By ~ 53

Author(s):

Åsa Öhagen ◽

Dana Gabuzda

Keyword(s):

Human Immunodeficiency Virus ◽

Dna Synthesis ◽

Virus Entry ◽

Wild Type ◽

The Core ◽

Immunodeficiency Virus ◽

The Stability ◽

Hiv 1

ABSTRACT The Vif protein of human immunodeficiency virus type 1 (HIV-1) is important for virion infectivity. Previous studies have shown thatvif-defective virions exhibit structural abnormalities in the virus core and are defective in the ability to complete proviral DNA synthesis in acutely infected cells. We developed novel assays to assess the relative stability of the core in HIV-1 virions. Using these assays, we examined the role of Vif in the stability of the HIV-1 core. The integrity of the core was examined following virion permeabilization or removal of the lipid envelope and treatment with various triggers, including S100 cytosol, deoxynucleoside triphosphates, detergents, NaCl, and buffers of different pH to mimic aspects of the uncoating and disassembly process which occurs after virus entry but preceding or during reverse transcription.vif mutant cores were more sensitive to disruption by all triggers tested than wild-type cores, as determined by endogenous reverse transcriptase (RT) assays, biochemical analyses, and electron microscopy. RT and the p7 nucleocapsid protein were released more readily from vif mutant virions than from wild-type virions, suggesting that the internal nucleocapsid is less stably packaged in the absence of Vif. Purified cores could be isolated from wild-type but not vif mutant virions by sedimentation through detergent-treated gradients. These results demonstrate that Vif increases the stability of virion cores. This may permit efficient viral DNA synthesis by preventing premature degradation or disassembly of viral nucleoprotein complexes during early events after virus entry.

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Mutations in the HIV-1 3’-polypurine tract can confer dolutegravir resistance

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01027-21 ◽

2021 ◽

Author(s):

José G. Dekker ◽

Bep Klaver ◽

Ben Berkhout ◽

Atze T. Das

Keyword(s):

Human Immunodeficiency Virus ◽

Polypurine Tract ◽

Letter To The Editor ◽

Immunodeficiency Virus ◽

Hiv 1 ◽

Human Immunodeficiency Virus 1

With interest we read the Letter to the Editor of Wei and Sluis-Cremer about the role of human immunodeficiency virus 1 (HIV-1) 3’polypurine tract (3’PPT) mutations in dolutegravir (DTG) resistance 1.…

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Postentry Restriction to Human Immunodeficiency Virus-Based Vector Transduction in Human Monocytes

Journal of Virology ◽

10.1128/jvi.75.12.5448-5456.2001 ◽

2001 ◽

Vol 75 (12) ◽

pp. 5448-5456 ◽

Cited By ~ 90

Author(s):

Stuart Neil ◽

Francisco Martin ◽

Yasuhiro Ikeda ◽

Mary Collins

Keyword(s):

Human Immunodeficiency Virus ◽

Calf Serum ◽

Human Monocytes ◽

Nuclear Entry ◽

Immunodeficiency Virus ◽

Central Polypurine Tract ◽

Antigen Presenting ◽

Hiv 1 ◽

Vector Transduction

ABSTRACT Cells of the monocyte lineage can be infected with human immunodeficiency virus type 1 (HIV-1) both during clinical infection and in vitro. The ability of HIV-1-based vectors to transduce human monocytes, monocyte-derived macrophages, and dendritic cells (DCs) was therefore examined, in order to develop an efficient protocol for antigen gene delivery to human antigen-presenting cells. Freshly isolated monocytes were refractory to HIV-1-based vector transduction but became transducible after in vitro differentiation to mature macrophages. This maturation-dependent transduction was independent of the HIV-1 accessory proteins Vif, Vpr, Vpu, and Nef in the packaging cells and of the central polypurine tract in the vector, and it was also observed with a vesicular stomatitis virus-pseudotyped HIV-1 provirus, defective only in envelope and Nef. The level and extent of reverse transcription of the HIV-1-based vector was similar after infection of immature monocytes and of mature macrophages. However, 2LTR vector circles could not be detected in monocytes, suggesting a block to vector nuclear entry in these cells. Transduction of freshly isolated monocytes exposed to HIV-1-based vector could be rescued by subsequent differentiation into DCs. This rescue was induced by fetal calf serum in the DC culture medium, which promoted vector nuclear entry.

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Mechanistic Role of Residue Gln151in Error Prone DNA Synthesis by Human Immunodeficiency Virus Type 1 (HIV-1) Reverse Transcriptase (RT)

Journal of Biological Chemistry ◽

10.1074/jbc.m200202200 ◽

2002 ◽

Vol 277 (25) ◽

pp. 22662-22669 ◽

Cited By ~ 28

Author(s):

Kellie K. Weiss ◽

Robert A. Bambara ◽

Baek Kim

Keyword(s):

Human Immunodeficiency Virus ◽

Reverse Transcriptase ◽

Dna Synthesis ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Immunodeficiency Virus ◽

Hiv 1

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From Capsids to Complexes: Expanding the Role of TRIM5α in the Restriction of Divergent RNA Viruses and Elements

Viruses ◽

10.3390/v13030446 ◽

2021 ◽

Vol 13 (3) ◽

pp. 446

Author(s):

Kevin M. Rose ◽

Stephanie J. Spada ◽

Rebecca Broeckel ◽

Kristin L. McNally ◽

Vanessa M. Hirsch ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Molecular Basis ◽

Human Population ◽

Rna Viruses ◽

Arms Race ◽

Innate Immune ◽

Immunodeficiency Virus ◽

Underlying Mechanisms ◽

Hiv 1

An evolutionary arms race has been ongoing between retroviruses and their primate hosts for millions of years. Within the last century, a zoonotic transmission introduced the Human Immunodeficiency Virus (HIV-1), a retrovirus, to the human population that has claimed the lives of millions of individuals and is still infecting over a million people every year. To counteract retroviruses such as this, primates including humans have evolved an innate immune sensor for the retroviral capsid lattice known as TRIM5α. Although the molecular basis for its ability to restrict retroviruses is debated, it is currently accepted that TRIM5α forms higher-order assemblies around the incoming retroviral capsid that are not only disruptive for the virus lifecycle, but also trigger the activation of an antiviral state. More recently, it was discovered that TRIM5α restriction is broader than previously thought because it restricts not only the human retroelement LINE-1, but also the tick-borne flaviviruses, an emergent group of RNA viruses that have vastly different strategies for replication compared to retroviruses. This review focuses on the underlying mechanisms of TRIM5α-mediated restriction of retroelements and flaviviruses and how they differ from the more widely known ability of TRIM5α to restrict retroviruses.

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Human Immunodeficiency Virus Inhibits Multilineage Hematopoiesis In Vivo

Journal of Virology ◽

10.1128/jvi.72.6.5121-5127.1998 ◽

1998 ◽

Vol 72 (6) ◽

pp. 5121-5127 ◽

Cited By ~ 42

Author(s):

Prasad S. Koka ◽

John K. Fraser ◽

Yvonne Bryson ◽

Gregory C. Bristol ◽

Grace M. Aldrovandi ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Progenitor Cells ◽

Ex Vivo ◽

Erythroid Differentiation ◽

Inhibitory Effect ◽

Immunodeficiency Virus ◽

The Many ◽

Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1)-infected individuals often exhibit multiple hematopoietic abnormalities reaching far beyond loss of CD4+ lymphocytes. We used the SCID-hu (Thy/Liv) mouse (severe combined immunodeficient mouse transplanted with human fetal thymus and liver tissues), which provides an in vivo system whereby human pluripotent hematopoietic progenitor cells can be maintained and undergo T-lymphoid differentiation and wherein HIV-1 infection causes severe depletion of CD4-bearing human thymocytes. Herein we show that HIV-1 infection rapidly and severely decreases the ex vivo recovery of human progenitor cells capable of differentiation into both erythroid and myeloid lineages. However, the total CD34+ cell population is not depleted. Combination antiretroviral therapy administered well after loss of multilineage progenitor activity reverses this inhibitory effect, establishing a causal role of viral replication. Taken together, our results suggest that pluripotent stem cells are not killed by HIV-1; rather, a later stage important in both myeloid and erythroid differentiation is affected. In addition, a primary virus isolated from a patient exhibiting multiple hematopoietic abnormalities preferentially depleted myeloid and erythroid colony-forming activity rather than CD4-bearing thymocytes in this system. Thus, HIV-1 infection perturbs multiple hematopoietic lineages in vivo, which may explain the many hematopoietic defects found in infected patients.

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Removal of a Single N-Linked Glycan in Human Immunodeficiency Virus Type 1 gp120 Results in an Enhanced Ability To Induce Neutralizing Antibody Responses

Journal of Virology ◽

10.1128/jvi.01691-07 ◽

2007 ◽

Vol 82 (2) ◽

pp. 638-651 ◽

Cited By ~ 127

Author(s):

Yun Li ◽

Bradley Cleveland ◽

Igor Klots ◽

Bruce Travis ◽

Barbra A. Richardson ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Pronounced Increase ◽

Enhanced Sensitivity ◽

Subtype B ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Glycans on human immunodeficiency virus (HIV) envelope protein play an important role in infection and evasion from host immune responses. To examine the role of specific glycans, we introduced single or multiple mutations into potential N-linked glycosylation sites in hypervariable regions (V1 to V3) of the env gene of HIV type 1 (HIV-1) 89.6. Three mutants tested showed enhanced sensitivity to soluble CD4. Mutant N7 (N197Q) in the carboxy-terminal stem of the V2 loop showed the most pronounced increase in sensitivity to broadly neutralizing antibodies (NtAbs), including those targeting the CD4-binding site (IgG1b12) and the V3 loop (447-52D). This mutant is also sensitive to CD4-induced NtAb 17b in the absence of CD4. Unlike the wild-type (WT) Env, mutant N7 mediates CD4-independent infection in U87-CXCR4 cells. To study the immunogenicity of mutant Env, we immunized pig-tailed macaques with recombinant vaccinia viruses, one expressing SIVmac239 Gag-Pol and the other expressing HIV-1 89.6 Env gp160 in WT or mutant forms. Animals were boosted 14 to 16 months later with simian immunodeficiency virus gag DNA and the cognate gp140 protein before intrarectal challenge with SHIV89.6P-MN. Day-of-challenge sera from animals immunized with mutant N7 Env had significantly higher and broader neutralizing activities than sera from WT Env-immunized animals. Neutralizing activity was observed against SHIV89.6, SHIV89.6P-MN, HIV-1 SF162, and a panel of subtype B primary isolates. Compared to control animals, immunized animals showed significant reduction of plasma viral load and increased survival after challenge, which correlated with prechallenge NtAb titers. These results indicate the potential advantages for glycan modification in vaccine design, although the role of specific glycans requires further examination.

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Reassessment of the Roles of Integrase and the Central DNA Flap in Human Immunodeficiency Virus Type 1 Nuclear Import

Journal of Virology ◽

10.1128/jvi.76.23.12087-12096.2002 ◽

2002 ◽

Vol 76 (23) ◽

pp. 12087-12096 ◽

Cited By ~ 109

Author(s):

Jeffrey D. Dvorin ◽

Peter Bell ◽

Gerd G. Maul ◽

Masahiro Yamashita ◽

Michael Emerman ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

In Situ Hybridization ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Nuclear Import ◽

Immunodeficiency Virus ◽

Central Polypurine Tract ◽

Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) can infect nondividing cells productively because the nuclear import of viral nucleic acids occurs in the absence of cell division. A number of viral factors that are present in HIV-1 preintegration complexes (PICs) have been assigned functions in nuclear import, including an essential valine at position 165 in integrase (IN-V165) and the central polypurine tract (cPPT). In this article, we report a comparison of the replication and infection characteristics of viruses with disruptions in the cPPT and IN-V165. We found that viruses with cPPT mutations still replicated productively in both dividing and nondividing cells, while viruses with a mutation at IN-V165 did not. Direct observation of the subcellular localization of HIV-1 cDNAs by fluorescence in situ hybridization revealed that cDNAs synthesized by both mutant viruses were readily detected in the nucleus. Thus, neither the cPPT nor the valine residue at position 165 of integrase is essential for the nuclear import of HIV-1 PICs.

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