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Tada T, Zhang Y, Kong D, Tanaka M, Yao W, Kameoka M, Ueno T, Fujita H, Tokunaga K. Further Characterization of the Antiviral Transmembrane Protein MARCH8. Cells 2024; 13:698. [PMID: 38667313 PMCID: PMC11049619 DOI: 10.3390/cells13080698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
The cellular transmembrane protein MARCH8 impedes the incorporation of various viral envelope glycoproteins, such as the HIV-1 envelope glycoprotein (Env) and vesicular stomatitis virus G-glycoprotein (VSV-G), into virions by downregulating them from the surface of virus-producing cells. This downregulation significantly reduces the efficiency of virus infection. In this study, we aimed to further characterize this host protein by investigating its species specificity and the domains responsible for its antiviral activity, as well as its ability to inhibit cell-to-cell HIV-1 infection. We found that the antiviral function of MARCH8 is well conserved in the rhesus macaque, mouse, and bovine versions. The RING-CH domains of these versions are functionally important for inhibiting HIV-1 Env and VSV-G-pseudovirus infection, whereas tyrosine motifs are crucial for the former only, consistent with findings in human MARCH8. Through analysis of chimeric proteins between MARCH8 and non-antiviral MARCH3, we determined that both the N-terminal and C-terminal cytoplasmic tails, as well as presumably the N-terminal transmembrane domain, of MARCH8 are critical for its antiviral activity. Notably, we found that MARCH8 is unable to block cell-to-cell HIV-1 infection, likely due to its insufficient downregulation of Env. These findings offer further insights into understanding the biology of this antiviral transmembrane protein.
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Affiliation(s)
- Takuya Tada
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Yanzhao Zhang
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
- Key Laboratory of Environmental Stress and Chronic Disease Control and Prevention, Ministry of Education, China Medical University, Shenyang 110122, China
- Department of Health Laboratory Technology, School of Public Health, China Medical University, Shenyang 110122, China
| | - Dechuan Kong
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
- Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-8555, Japan;
| | - Michiko Tanaka
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
| | - Weitong Yao
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
- Shenzhen Bay Laboratory, Institute of Chemical Biology, Shenzhen 518132, China
| | - Masanori Kameoka
- Department of Public Health, Kobe University Graduate School of Health Sciences, Kobe 650-0017, Japan;
| | - Takamasa Ueno
- Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-8555, Japan;
| | - Hideaki Fujita
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo 859-3298, Japan;
| | - Kenzo Tokunaga
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; (T.T.); (Y.Z.); (D.K.); (W.Y.)
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Chintala K, Yandrapally S, Faiz W, Kispotta CR, Sarkar S, Mishra K, Banerjee S. The nuclear pore protein NUP98 impedes LTR-driven basal gene expression of HIV-1, viral propagation, and infectivity. Front Immunol 2024; 15:1330738. [PMID: 38449868 PMCID: PMC10914986 DOI: 10.3389/fimmu.2024.1330738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 01/31/2024] [Indexed: 03/08/2024] Open
Abstract
Nucleoporins (NUPs) are cellular effectors of human immunodeficiency virus-1 (HIV-1) replication that support nucleocytoplasmic trafficking of viral components. However, these also non-canonically function as positive effectors, promoting proviral DNA integration into the host genome and viral gene transcription, or as negative effectors by associating with HIV-1 restriction factors, such as MX2, inhibiting the replication of HIV-1. Here, we investigated the regulatory role of NUP98 on HIV-1 as we observed a lowering of its endogenous levels upon HIV-1 infection in CD4+ T cells. Using complementary experiments in NUP98 overexpression and knockdown backgrounds, we deciphered that NUP98 negatively affected HIV-1 long terminal repeat (LTR) promoter activity and lowered released virus levels. The negative effect on promoter activity was independent of HIV-1 Tat, suggesting that NUP98 prevents the basal viral gene expression. ChIP-qPCR showed NUP98 to be associated with HIV-1 LTR, with the negative regulatory element (NRE) of HIV-1 LTR playing a dominant role in NUP98-mediated lowering of viral gene transcription. Truncated mutants of NUP98 showed that the attenuation of HIV-1 LTR-driven transcription is primarily contributed by its N-terminal region. Interestingly, the virus generated from the producer cells transiently expressing NUP98 showed lower infectivity, while the virus generated from NUP98 knockdown CD4+ T cells showed higher infectivity as assayed in TZM-bl cells, corroborating the anti-HIV-1 properties of NUP98. Collectively, we show a new non-canonical function of a nucleoporin adding to the list of moonlighting host factors regulating viral infections. Downregulation of NUP98 in a host cell upon HIV-1 infection supports the concept of evolutionary conflicts between viruses and host antiviral factors.
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Affiliation(s)
| | | | | | | | | | | | - Sharmistha Banerjee
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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Kusagawa S, Kawana-Tachikawa A, Matsuoka S. Establishment of qualitative human immunodeficiency virus type 1 nucleic acid amplification test as an adjunct confirmatory test in low-prevalence areas and small- and medium-sized diagnostic laboratories. Heliyon 2024; 10:e24451. [PMID: 38304812 PMCID: PMC10831601 DOI: 10.1016/j.heliyon.2024.e24451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 12/26/2023] [Accepted: 01/09/2024] [Indexed: 02/03/2024] Open
Abstract
Two simple and inexpensive in-house qualitative human immunodeficiency virus type 1 nucleotide amplification tests (HIV-1 NATs) were established as adjunct confirmatory HIV test for HIV antigen (Ag)-positive specimens identified from HIV screening test and for patients with indeterminate or negative HIV antibody (Ab) confirmatory test results. The limit of detection was <1000 copies/mL, which is lower than that of the HIV Ag/Ab combination assay. One test using QL1 detected all 11 HIV-1 subtypes/circulating recombinant forms/group samples with almost equal analytical sensitivity, and the other test, using QL2, also detected all, except for two group O samples. In the examination of 28 HIV-1 Ag-positive samples using Determine HIV Early Detect, 27 samples were reactive and one HIV-1 Ag-pseudo-positive sample was non-reactive using both methods. These in-house qualitative HIV-1 NATs are useful for confirming HIV-1 Ag-positive cases and excluding HIV-1 Ag false-positive cases in areas with low HIV prevalence and small- and medium-sized diagnostic laboratories.
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Affiliation(s)
- Shigeru Kusagawa
- AIDS Research Center, National Institute of Infectious Diseases, Japan
| | | | - Saori Matsuoka
- AIDS Research Center, National Institute of Infectious Diseases, Japan
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Aromatic Side Chain at Position 412 of SERINC5 Exerts Restriction Activity toward HIV-1 and Other Retroviruses. J Virol 2021; 95:e0063421. [PMID: 34190600 DOI: 10.1128/jvi.00634-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The host transmembrane protein SERINC5 is incorporated into viral particles and restricts infection by certain retroviruses. However, what motif of SERINC5 mediates this process remains elusive. By conducting mutagenesis analyses, we found that the substitution of phenylalanine with alanine at position 412 (F412A) resulted in a >75-fold reduction in SERINC5's restriction function. The F412A substitution also resulted in the loss of SERINC5's function to sensitize HIV-1 neutralization by antibodies recognizing the envelope's membrane proximal region. A series of biochemical analyses revealed that F412A showed steady-state protein expression, localization at the cellular membrane, and incorporation into secreted virus particles to a greater extent than in the wild type. Furthermore, introduction of several amino acid mutations at this position revealed that the aromatic side chains, including phenylalanine, tyrosine, and tryptophan, were required to maintain SERINC5 functions to impair the virus-cell fusion process and virion infectivity. Moreover, the wild-type SERINC5 restricted infection of lentiviruses pseudotyped with envelopes of murine leukemia viruses, simian immunodeficiency virus, and HIV-2, and F412A abrogated this function. Taken together, our results highlight the importance of the aromatic side chain at SERINC5 position 412 to maintain its restriction function against diverse retrovirus envelopes. IMPORTANCE The host protein SERINC5 is incorporated into progeny virions of certain retroviruses and restricts the infectivity of these viruses or sensitizes the envelope glycoprotein to a class of neutralizing antibodies. However, how and which part of SERINC5 engages with the diverse array of retroviral envelopes and exerts its antiretroviral functions remain elusive. During mutagenesis analyses, we eventually found that the single substitution of phenylalanine with alanine, but not with tyrosine or tryptophan, at position 412 (F412A) resulted in the loss of SERINC5's functions toward diverse retroviruses, whereas F412A showed steady-state protein expression, localization at the cellular membrane, and incorporation into progeny virions to a greater extent than the wild type. Results suggest that the aromatic side chain at position 412 of SERINC5 plays a critical role in mediating antiviral functions toward various retroviruses, thus providing additional important information regarding host and retrovirus interaction.
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Zhang Y, Tada T, Ozono S, Kishigami S, Fujita H, Tokunaga K. MARCH8 inhibits viral infection by two different mechanisms. eLife 2020; 9:57763. [PMID: 32778221 PMCID: PMC7419139 DOI: 10.7554/elife.57763] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 07/30/2020] [Indexed: 12/03/2022] Open
Abstract
Membrane-associated RING-CH 8 (MARCH8) inhibits infection with both HIV-1 and vesicular stomatitis virus G-glycoprotein (VSV-G)-pseudotyped viruses by reducing virion incorporation of envelope glycoproteins. The molecular mechanisms by which MARCH8 targets envelope glycoproteins remain unknown. Here, we show two different mechanisms by which MARCH8 inhibits viral infection. Viruses pseudotyped with the VSV-G mutant, in which cytoplasmic lysine residues were mutated, were insensitive to the inhibitory effect of MARCH8, whereas those with a similar lysine mutant of HIV-1 Env remained sensitive to it. Indeed, the wild-type VSV-G, but not its lysine mutant, was ubiquitinated by MARCH8. Furthermore, the MARCH8 mutant, which had a disrupted cytoplasmic tyrosine motif that is critical for intracellular protein sorting, did not inhibit HIV-1 Env-mediated infection, while it still impaired infection by VSV-G-pseudotyped viruses. Overall, we conclude that MARCH8 reduces viral infectivity by downregulating envelope glycoproteins through two different mechanisms mediated by a ubiquitination-dependent or tyrosine motif-dependent pathway.
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Affiliation(s)
- Yanzhao Zhang
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takuya Tada
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Seiya Ozono
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan.,Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, Japan
| | - Satoshi Kishigami
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, Japan
| | - Hideaki Fujita
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Nagasaki, Japan
| | - Kenzo Tokunaga
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
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Mavhandu LG, Cheng H, Bor YC, Tebit DM, Hammarskjold ML, Rekosh D, Bessong PO. Development of a pseudovirus assay and evaluation to screen natural products for inhibition of HIV-1 subtype C reverse transcriptase. JOURNAL OF ETHNOPHARMACOLOGY 2020; 258:112931. [PMID: 32360797 DOI: 10.1016/j.jep.2020.112931] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/20/2020] [Accepted: 04/27/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Medicinal plants are used in the management of Human Immunodeficiency Virus and Acquired Immunodeficiency Syndrome (HIV/AIDS) in many developing country settings where HIV-1 subtype C drives the epidemic. Efforts to identify plant derived molecules with anti-HIV properties require reproducible assay systems for routine screening of selected plant compounds. Although a number of standardized HIV-1 pseudoviruses have been generated to assess infectivity, replicability or reproducibility, HIV-1 subtype C (HIV-1-C) pseudoviruses have not been comprehensively characterized to identify inhibitory plant substances. AIM OF THE STUDY The current study aimed at developing an HIV-1-C pseudovirus assay, and evaluate plant substances targeting reverse transcriptase (RT) activity. MATERIALS AND METHODS HIV-1 subtype C pseudoviruses containing a luciferase reporter gene were generated by transfection of human 293T cells. HIV-1 subtype B (HIV-1-B) wild type pseudoviruses and mutants resistant to nucleoside and non-nucleoside RT inhibitors were also generated and used as controls. Selected plant substances and the RT inhibitors Zidovudine (AZT) and Nevirapine (NVP), were used to evaluate inhibition. Pseudovirus infectivity was determined by luciferase measurement in CF2/CD4+/CCR5 cells, and cytotoxicity was determined using the MTT assay. AZT and NVP inhibited wild type pseudoviruses in a dose dependent manner, with IC50 values in the nanomolar range. RESULTS Pseudoviruses harbouring RT drug resistance mutations were poorly suppressed by AZT and NVP. Catechin, obtained from Peltophorum africanum inhibited HIV-1-C and HIV-1-B pseudoviruses with selective indices of 6304 μM (IC50: 0.49 μM, CC50: 3089 μM) and 1343 μM (IC50: 2.3 μM, CC50: 3089 μM), respectively; while the methanol root crude extract of Elaeodendron transvaalense gave IC50 values of 11.11 μg/ml and 16.86 μg/ml, respectively. CONCLUSION The developed HIV-1-C pseudovirus assay can be used to screen plant substances for RT inhibition, and may have utility in settings with limited access to high level biosafety facilities.
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Affiliation(s)
- Lufuno Grace Mavhandu
- HIV/AIDS & Global Health Research Programme, University of Venda, PMB X5050, Thohoyandou, 0950, South Africa.
| | - Hua Cheng
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, Department of Microbiology, Immunology and Cancer Biology, University of Virginia, P.O. Box 800734, Charlottesville, VA, 22908, USA; Shanghai Municipal Center for Disease Control and Prevention, Department of HIV, STD and Leprosy, 1380 Zhongshan Road, Shanghai, 200336, China.
| | - Yeou-Cheng Bor
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, Department of Microbiology, Immunology and Cancer Biology, University of Virginia, P.O. Box 800734, Charlottesville, VA, 22908, USA; Ambassadors for Christ, 21 Ambassador Drive, Paradise, PA, 17562, USA.
| | - Denis Manga Tebit
- HIV/AIDS & Global Health Research Programme, University of Venda, PMB X5050, Thohoyandou, 0950, South Africa; Myles H. Thaler Center for AIDS and Human Retrovirus Research, Department of Microbiology, Immunology and Cancer Biology, University of Virginia, P.O. Box 800734, Charlottesville, VA, 22908, USA; Global Biomed Scientific LLC, PO Box 2368, Forest, VA, 24551, USA.
| | - Marie-Louise Hammarskjold
- HIV/AIDS & Global Health Research Programme, University of Venda, PMB X5050, Thohoyandou, 0950, South Africa; Myles H. Thaler Center for AIDS and Human Retrovirus Research, Department of Microbiology, Immunology and Cancer Biology, University of Virginia, P.O. Box 800734, Charlottesville, VA, 22908, USA.
| | - David Rekosh
- HIV/AIDS & Global Health Research Programme, University of Venda, PMB X5050, Thohoyandou, 0950, South Africa; Myles H. Thaler Center for AIDS and Human Retrovirus Research, Department of Microbiology, Immunology and Cancer Biology, University of Virginia, P.O. Box 800734, Charlottesville, VA, 22908, USA.
| | - Pascal Obong Bessong
- HIV/AIDS & Global Health Research Programme, University of Venda, PMB X5050, Thohoyandou, 0950, South Africa.
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Trivedi J, Ghosh P, Mitra D. N-p-Tosyl-L-phenylalanine chloromethyl ketone (TPCK) inhibits HIV-1 by suppressing the activity of viral protease. Biochem Biophys Res Commun 2020; 527:167-172. [PMID: 32446362 DOI: 10.1016/j.bbrc.2020.04.096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 04/18/2020] [Indexed: 11/28/2022]
Abstract
Human Immunodeficiency Virus (HIV), the etiological agent for Acquired Immunodeficiency Syndrome (AIDS), continues to kill humans despite stupendous advances in antiviral research. With the presently available combination antiretroviral therapeutic arsenal, AIDS is now a manageable disease but with no cure available till date. The development of novel antivirals consumes an extensive amount of time and resources. Hence, repurposing of the established gold standard molecules for their anti-HIV application is enormously advantageous. In this study, we report that N-p-Tosyl-L-phenylalanine chloromethyl ketone (TPCK) inhibits HIV-1 replication in a highly-conserved manner. Further, TPCK inhibits HIV-1 replication at the late stages of its life cycle by impeding viral protease (PR) enzyme activity. Additionally, our results demonstrate that the combination of TPCK with established HIV-1 PR inhibitors shows significant synergistic inhibitory potential, suggesting the potential use of TPCK in cART regimen. Collectively, we report the anti-HIV activity of TPCK, which should be further characterized for its translational applications.
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Affiliation(s)
- Jay Trivedi
- National Centre for Cell Science, S. P. Pune University Campus, Pune, India.
| | - Payel Ghosh
- Bioinformatics Centre, Savitribai Phule Pune University, Pune, India.
| | - Debashis Mitra
- National Centre for Cell Science, S. P. Pune University Campus, Pune, India; Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad, India.
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Padmanabhan U, Dahake R, Chowdhary AS, Koka PS. HIV-1 inhibits haematopoiesis via microRNA secreted by virus-infected CD4+ T cells. Eur J Haematol 2019; 104:170-180. [PMID: 31733152 DOI: 10.1111/ejh.13350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 11/02/2019] [Accepted: 11/06/2019] [Indexed: 11/30/2022]
Abstract
INTRODUCTION HIV-1-infected patients develop haematological disorders such as cytopenias. One possible explanation is the inhibition of haematopoiesis at the level of differentiation of CD34+ haematopoietic progenitor stem cells. Based on our previous studies, we hypothesised that there may be viral encoded, or host cellular factors which participate in the process of inhibition of haematopoiesis. MATERIALS AND METHODS Virus-depleted media from infected CD4+ T cells was prepared by filtration and added to CD34+ cell differentiation semisolid medium. We have also used the virus-depleted media to isolate host/viral factors including miRNA. Isolated miRNAs were screened for their haematopoietic inhibitory function using the miRNA mining approach. RESULTS Addition of virus-depleted media caused a 40% inhibition of differentiation of CD34+ cells into myeloid and erythroid colony formation. Real-time RT-PCR showed miR-15a and miR-24 from both pIndie-C1 and pNL4.3 HIV-1-infected cells showed a significant differential expression when compared to control media. CONCLUSION In this study, we have identified two miRNAs, miR-15a and miR-24 secreted from purified HIV-1-infected CD4+ T cells that inhibited CD34+ haematopoietic progenitor stem cell differentiation into myeloid and erythroid colonies in vitro.
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Affiliation(s)
- Usha Padmanabhan
- Department of Cell Biology, Haffkine Institute for Training, Research & Testing, Mumbai, India
| | - Ritwik Dahake
- Department of Virology & Immunology, Haffkine Institute for Training, Research & Testing, Mumbai, India
| | - Abhay S Chowdhary
- Department of Microbiology, School of Medicine, D Y Patil University, Navi Mumbai, India
| | - Prasad S Koka
- Department of Virology & Immunology, Haffkine Institute for Training, Research & Testing, Mumbai, India
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Doi N, Koma T, Adachi A, Nomaguchi M. Expression Level of HIV-1 Vif Can Be Fluctuated by Natural Nucleotide Variations in the vif-Coding and Regulatory SA1D2prox Sequences of the Proviral Genome. Front Microbiol 2019; 10:2758. [PMID: 31849897 PMCID: PMC6893887 DOI: 10.3389/fmicb.2019.02758] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 11/12/2019] [Indexed: 11/26/2022] Open
Abstract
Vif is required for HIV-1 replication in natural target cells by counteracting host restriction factors, APOBEC3 (A3) proteins. We recently demonstrated that Vif expression level can be changed by naturally occurring single-nucleotide variations within SA1D2prox of the HIV-1 genome. We also found that levels for vif/vpr mRNAs are inversely correlated. While amino acid sequence per se is critical for functionality, Vif expression level modulated by signal sequences in its coding region is likely to be important as well. There are two splicing sites in the region involved in vpr expression. To reveal possible fluctuations of Vif-expression level, we examined SA1D2prox and vif gene by chimeric approaches using HIV-1 subtypes B and C with distinct anti-A3 activity. In this report, recombinant clones in subtype B backbone carrying chimeric sequences with respect to SA1D2prox/vif and those within the vif-coding region were generated. Of these, clones containing vif-coding sequence of subtype C, especially its 3′ region, expressed vif/Vif at a decreased level but did at an increased level for vpr/Vpr. Clones with reduced vif/Vif level grew similarly or slightly better than a parental clone in weakly A3G-positive cells but more poorly in highly A3G-expressing cells. Three clones with this property were also tested for their A3-degrading activity. One of the clones appeared to have some defect in addition to the poor ability to express vif/Vif. Taken all together, our results show that natural variations in the SA1D2prox and vif-coding region can change the Vif-expression level and affect the HIV-1 replication potential.
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Affiliation(s)
- Naoya Doi
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
| | - Takaaki Koma
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
| | - Akio Adachi
- Department of Microbiology, Kansai Medical University, Osaka, Japan
| | - Masako Nomaguchi
- Department of Microbiology, Tokushima University Graduate School of Medical Science, Tokushima, Japan
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Trivedi J, Alam A, Joshi S, Kumar TP, Chippala V, Mainkar PS, Chandrasekhar S, Chattopadhyay S, Mitra D. A novel isothiocyanate derivative inhibits HIV-1 gene expression and replication by modulating the nuclear matrix associated protein SMAR1. Antiviral Res 2019; 173:104648. [PMID: 31706900 DOI: 10.1016/j.antiviral.2019.104648] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 10/24/2019] [Accepted: 11/04/2019] [Indexed: 12/30/2022]
Abstract
The essential role of SMAR1 in HIV-1 transcription and LTR driven gene expression suggests SMAR1 as an HIV dependency factor (HDF) and a potential anti-HIV therapeutic target. Here, we report for the first time, anti-HIV activity of 8 novel isothiocyanate (ITC) derivatives that differentially stabilise SMAR1. Out of 8 novel ITC derivatives, SCS-OCL-381 was observed to inhibit HIV-1 replication most significantly at the noncytotoxic concentration in reporter T-cell line, CEM-GFP. Further, the highly conserved anti-HIV activity of SCS-OCL-381 is a cell type, virus isolate and viral load independent phenomena and is approximately 3 fold more effective than the representative ITC, Sulforaphane (SFN). Further, SCS-OCL-381 does not hamper the activity of viral enzymes reverse transcriptase, integrase and protease. Mechanistically, SCS-OCL-381 stabilises SMAR1 which, otherwise undergoes proteasomal degradation upon HIV-1 infection in T-cells. This stabilisation results in the recruitment of repressor complex on HIV-1 LTR resulting in repression of LTR mediated transcription and gene expression. These inhibitory consequences were further confirmed by reporter based LTR activity assays in different cell lines. Taken together, these findings highlight the anti-HIV potential of novel ITC derivatives by the stabilisation of SMAR1 and strongly support further in vivo characterisation and potential translational applications of SCS-OCL-381.
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Affiliation(s)
- Jay Trivedi
- National Centre for Cell Science, Pune University Campus, Pune, India.
| | - Aftab Alam
- National Centre for Cell Science, Pune University Campus, Pune, India.
| | - Shruti Joshi
- National Centre for Cell Science, Pune University Campus, Pune, India.
| | | | | | - Prathama S Mainkar
- CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, India.
| | | | - Samit Chattopadhyay
- National Centre for Cell Science, Pune University Campus, Pune, India; CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata, India.
| | - Debashis Mitra
- National Centre for Cell Science, Pune University Campus, Pune, India; Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad, India.
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Discovery of 2-isoxazol-3-yl-acetamide analogues as heat shock protein 90 (HSP90) inhibitors with significant anti-HIV activity. Eur J Med Chem 2019; 183:111699. [PMID: 31561045 DOI: 10.1016/j.ejmech.2019.111699] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 09/11/2019] [Accepted: 09/12/2019] [Indexed: 12/17/2022]
Abstract
The recent burst of explorations on heat shock protein 90 (HSP90) in virus research supports its emergence as a promising target to overcome the drawbacks of current antiviral therapeutic regimen. In continuation of our efforts towards the discovery of novel anti-retroviral molecules, we designed, synthesized fifteen novels 2-isoxazol-3-yl-acetamide based compounds (2a-o) followed by analysis of their anti-HIV activity and cytotoxicity studies. 2a-b, 2e, 2j, and 2l-m were found to be active with inhibitory potentials >80% at their highest non-cytotoxic concentration (HNC). Further characterization of anti-HIV activity of these molecules suggests that 2l has ∼3.5 fold better therapeutic index than AUY922, the second generation HSP90 inhibitor. The anti-HIV activity of 2l is a cell type, virus isolate and viral load independent phenomena. Interestingly, 2l does not significantly modulate viral enzymes like Reverse Transcriptase (RT), Integrase (IN) and Protease (PR) as compared to their known inhibitors in a cell free in vitro assay system at its HNC. Further, 2l mediated inhibition of HSP90 attenuates HIV-1 LTR driven gene expression. Taken together, structural rationale, modeling studies and characterization of biological activities suggest that this novel scaffold can attenuate HIV-1 replication significantly within the host and thus opens a new horizon to develop novel anti-HIV therapeutic candidates.
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Izumida M, Suga K, Ishibashi F, Kubo Y. The Spirocyclic Imine from a Marine Benthic Dinoflagellate, Portimine, Is a Potent Anti-Human Immunodeficiency Virus Type 1 Therapeutic Lead Compound. Mar Drugs 2019; 17:md17090495. [PMID: 31450557 PMCID: PMC6780162 DOI: 10.3390/md17090495] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/13/2019] [Accepted: 08/22/2019] [Indexed: 02/04/2023] Open
Abstract
In this study, we aimed to find chemicals from lower sea animals with defensive effects against human immunodeficiency virus type 1 (HIV-1). A library of marine natural products consisting of 80 compounds was screened for activity against HIV-1 infection using a luciferase-encoding HIV-1 vector. We identified five compounds that decreased luciferase activity in the vector-inoculated cells. In particular, portimine, isolated from the benthic dinoflagellate Vulcanodinium rugosum, exhibited significant anti-HIV-1 activity. Portimine inhibited viral infection with an 50% inhibitory concentration (IC50) value of 4.1 nM and had no cytotoxic effect on the host cells at concentrations less than 200 nM. Portimine also inhibited vesicular stomatitis virus glycoprotein (VSV-G)-pseudotyped HIV-1 vector infection. This result suggested that portimine mainly targeted HIV-1 Gag or Pol protein. To analyse which replication steps portimine affects, luciferase sequences were amplified by semi-quantitative PCR in total DNA. This analysis revealed that portimine inhibits HIV-1 vector infection before or at the reverse transcription step. Portimine has also been shown to have a direct effect on reverse transcriptase using an in vitro reverse transcriptase assay. Portimine efficiently inhibited HIV-1 replication and is a potent lead compound for developing novel therapeutic drugs against HIV-1-induced diseases.
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Affiliation(s)
- Mai Izumida
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan.
- Department of Community Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523, Japan.
| | - Koushirou Suga
- Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - Fumito Ishibashi
- Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - Yoshinao Kubo
- Program for Nurturing Global Leaders in Tropical Medicine and Emerging Communicable Diseases, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523, Japan.
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13
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Ajasin DO, Rao VR, Wu X, Ramasamy S, Pujato M, Ruiz AP, Fiser A, Bresnick AR, Kalpana GV, Prasad VR. CCL2 mobilizes ALIX to facilitate Gag-p6 mediated HIV-1 virion release. eLife 2019; 8:35546. [PMID: 31172941 PMCID: PMC6592687 DOI: 10.7554/elife.35546] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/06/2019] [Indexed: 12/22/2022] Open
Abstract
Cellular ESCRT machinery plays pivotal role in HIV-1 budding and release. Extracellular stimuli that modulate HIV-1 egress are currently unknown. We found that CCL2 induced by HIV-1 clade B (HIV-1B) infection of macrophages enhanced virus production, while CCL2 immuno-depletion reversed this effect. Additionally, HIV-1 clade C (HIV-1C) was refractory to CCL2 levels. We show that CCL2-mediated increase in virus production requires Gag late motif LYPX present in HIV-1B, but absent in HIV-1C, and ALIX protein that recruits ESCRT III complex. CCL2 immuno-depletion sequestered ALIX to F-actin structures, while CCL2 addition mobilized it to cytoplasm facilitating Gag-ALIX binding. The LYPX motif improves virus replication and its absence renders the virus less fit. Interestingly, novel variants of HIV-1C with PYRE/PYKE tetrapeptide insertions in Gag-p6 conferred ALIX binding, CCL2-responsiveness and enhanced virus replication. These results, for the first time, indicate that CCL2 mediates ALIX mobilization from F-actin and enhances HIV-1 release and fitness.
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Affiliation(s)
- David O Ajasin
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, United States
| | - Vasudev R Rao
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, United States
| | - Xuhong Wu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, United States
| | - Santhamani Ramasamy
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, United States
| | - Mario Pujato
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, United States
| | - Arthur P Ruiz
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, United States
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, United States
| | - Anne R Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, United States
| | - Ganjam V Kalpana
- Department of Genetics, Albert Einstein College of Medicine, Bronx, United States
| | - Vinayaka R Prasad
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, United States
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14
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A Naturally Occurring Polymorphism in the HIV-1 Tat Basic Domain Inhibits Uptake by Bystander Cells and Leads to Reduced Neuroinflammation. Sci Rep 2019; 9:3308. [PMID: 30824746 PMCID: PMC6397180 DOI: 10.1038/s41598-019-39531-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 01/07/2019] [Indexed: 01/28/2023] Open
Abstract
HIV-1 Tat protein contributes to HIV-neuropathogenesis in several ways including its ability to be taken up by uninfected bystander CNS cells and to activate inflammatory host genes causing synaptic injury. Here, we report that in the globally dominant HIV-1 clade C, Tat displays a naturally occurring polymorphism, R57S, in its basic domain, which mediates cellular uptake. We examined the effect of this polymorphism on Tat uptake and its consequences for cellular gene transactivation. In decapeptides corresponding to the basic domain, a R57S substitution caused up to a 70% reduction in uptake. We also used a transcellular Tat transactivation assay, where we expressed Tat proteins of HIV-1 clade B (Tat-B) or C (Tat-C) or their position 57 variants in HeLa cells. We quantified the secreted Tat proteins and measured their uptake by TZM-bl cells, which provide readout via an HIV-1 Tat-responsive luciferase gene. Transactivation by Tat-B was significantly reduced by R57S substitution, while that of Tat-C was enhanced by the reciprocal S57R substitution. Finally, we exposed microglia to Tat variants and found that R57 is required for maximal neuroinflammation. The R57S substitution dampened this response. Thus, genetic variations can modulate the ability of HIV-1 Tat to systemically disseminate neuroinflammation.
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15
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PYRE insertion within HIV-1 subtype C p6-Gag functions as an ALIX-dependent late domain. Sci Rep 2018; 8:8917. [PMID: 29891975 PMCID: PMC5995805 DOI: 10.1038/s41598-018-27162-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 05/18/2018] [Indexed: 11/23/2022] Open
Abstract
ALG-2 interacting protein X (ALIX) links HIV-1 Gag to the components of ESCRT-III. HIV-1 engages the ALIX via its nucleocapsid and LYPXnL motif in p6. Overexpression of ALIX corrects the release defect of PTAP deleted HIV-1 via LYPXnL/ALIX pathway. However, HIV-1 subtype C lacks the LYPXnL motif and hence cannot employ LYPXnL/ALIX mechanism. Though the preferential occurrences of PYXE insertion in HIV-1 C p6 is predicted to restore the ALIX binding site there is no functional proof to support these observations. In this study we show that HIV-1 construct with subtype C p6 having PTAP deletion and PYRE insertion (pNL-INp6ΔPTAP/PYRE) could respond to ALIX overexpression. Notably, conserved Phenyl alanine residue (F676) in ALIX was critical for ALIX mediated release of pNL-INp6ΔPTAP/PYRE implying the critical role of this hydrophobic patch in ALIX recruitment. In addition, we show that Nedd4-1 could also correct the release defect of pNL-INp6ΔPTAP/PYRE. Moreover, Nedd4-1 was more robust compared to ALIX in its ability to stimulate the release of pNL-INp6ΔPTAP/PYRE. Replication kinetic data highlights the positive effect of PYRE insertion on virus replication. In summary, our data reveals the functional role of PYRE insertion towards the cooperative mechanism of ALIX/Nedd4-1 in virus release in the absence of PTAP/Tsg101 pathway.
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16
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Microbial Natural Product Alternariol 5-O-Methyl Ether Inhibits HIV-1 Integration by Blocking Nuclear Import of the Pre-Integration Complex. Viruses 2017; 9:v9050105. [PMID: 28489061 PMCID: PMC5454418 DOI: 10.3390/v9050105] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/19/2017] [Accepted: 05/05/2017] [Indexed: 02/07/2023] Open
Abstract
While Highly Active Antiretroviral Therapy (HAART) has significantly decreased the mortality of human immunodeficiency virus (HIV)-infected patients, emerging drug resistance to approved HIV-1 integrase inhibitors highlights the need to develop new antivirals with novel mechanisms of action. In this study, we screened a library of microbial natural compounds from endophytic fungus Colletotrichum sp. and identified alternariol 5-O-methyl ether (AME) as a compound that inhibits HIV-1 pre-integration steps. Time-of addition analysis, quantitative real-time PCR, confocal microscopy, and WT viral replication assay were used to elucidate the mechanism. As opposed to the approved integrase inhibitor Raltegravir, AME reduced both the integrated viral DNA and the 2-long terminal repeat (2-LTR) circular DNA, which suggests that AME impairs the nuclear import of viral DNA. Further confocal microscopy studies showed that AME specifically blocks the nuclear import of HIV-1 integrase and pre-integration complex without any adverse effects on the importin α/β and importin β-mediated nuclear import pathway in general. Importantly, AME inhibited Raltegravir-resistant HIV-1 strains and exhibited a broad anti-HIV-1 activity in diverse cell lines. These data collectively demonstrate the potential of AME for further development into a new HIV inhibitor, and suggest the utility of viral DNA nuclear import as a target for anti-HIV drug discovery.
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17
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Functional Incompatibility between the Generic NF-κB Motif and a Subtype-Specific Sp1III Element Drives the Formation of the HIV-1 Subtype C Viral Promoter. J Virol 2016; 90:7046-7065. [PMID: 27194770 DOI: 10.1128/jvi.00308-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/12/2016] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED Of the various genetic subtypes of human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) and simian immunodeficiency virus (SIV), only in subtype C of HIV-1 is a genetically variant NF-κB binding site found at the core of the viral promoter in association with a subtype-specific Sp1III motif. How the subtype-associated variations in the core transcription factor binding sites (TFBS) influence gene expression from the viral promoter has not been examined previously. Using panels of infectious viral molecular clones, we demonstrate that subtype-specific NF-κB and Sp1III motifs have evolved for optimal gene expression, and neither of the motifs can be replaced by a corresponding TFBS variant. The variant NF-κB motif binds NF-κB with an affinity 2-fold higher than that of the generic NF-κB site. Importantly, in the context of an infectious virus, the subtype-specific Sp1III motif demonstrates a profound loss of function in association with the generic NF-κB motif. An additional substitution of the Sp1III motif fully restores viral replication, suggesting that the subtype C-specific Sp1III has evolved to function with the variant, but not generic, NF-κB motif. A change of only two base pairs in the central NF-κB motif completely suppresses viral transcription from the provirus and converts the promoter into heterochromatin refractory to tumor necrosis factor alpha (TNF-α) induction. The present work represents the first demonstration of functional incompatibility between an otherwise functional NF-κB motif and a unique Sp1 site in the context of an HIV-1 promoter. Our work provides important leads as to the evolution of the HIV-1 subtype C viral promoter with relevance for gene expression regulation and viral latency. IMPORTANCE Subtype-specific genetic variations provide a powerful tool to examine how these variations offer a replication advantage to specific viral subtypes, if any. Only in subtype C of HIV-1 are two genetically distinct transcription factor binding sites positioned at the most critical location of the viral promoter. Since a single promoter regulates viral gene expression, the promoter variations can play a critical role in determining the replication fitness of the viral strains. Our work for the first time provides a scientific explanation for the presence of a unique NF-κB binding motif in subtype C, a major HIV-1 genetic family responsible for half of the global HIV-1 infections. The results offer compelling evidence that the subtype C viral promoter not only is stronger but also is endowed with a qualitative gain-of-function advantage. The genetically variant NF-κB and the Sp1III motifs may be respond differently to specific cell signal pathways, and these mechanisms must be examined.
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18
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MARCH8 inhibits HIV-1 infection by reducing virion incorporation of envelope glycoproteins. Nat Med 2015; 21:1502-7. [PMID: 26523972 DOI: 10.1038/nm.3956] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 08/27/2015] [Indexed: 02/06/2023]
Abstract
Membrane-associated RING-CH 8 (MARCH8) is one of 11 members of the recently discovered MARCH family of RING (really interesting new gene)-finger E3 ubiquitin ligases. MARCH8 downregulates several host transmembrane proteins, including major histocompatibility complex (MHC)-II, CD86, interleukin (IL)-1 receptor accessory protein, TNF-related apoptosis-inducing ligand (TRAIL) receptor 1 and the transferrin receptor. However, its physiological roles remain largely unknown. Here we identify MARCH8 as a novel antiviral factor. The ectopic expression of MARCH8 in virus-producing cells does not affect levels of lentivirus production, but it does markedly reduce viral infectivity. MARCH8 blocks the incorporation of HIV-1 envelope glycoprotein into virus particles by downregulating it from the cell surface, probably through their interaction, resulting in a substantial reduction in the efficiency of viral entry. The inhibitory effect of MARCH8 on vesicular stomatitis virus G-glycoprotein is even more remarkable, suggesting a broad-spectrum inhibition of enveloped viruses by MARCH8. Notably, the endogenous expression of MARCH8 is high in monocyte-derived macrophages and dendritic cells, and MARCH8 knockdown or knockout in macrophages significantly increases the infectivity of virions produced by these cells. Our findings thus indicate that MARCH8 is highly expressed in terminally differentiated myeloid cells, and that it is a potent antiviral protein that targets viral envelope glycoproteins and reduces their incorporation into virions.
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19
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Sneha Priya R, Veena M, Kalisz I, Whitney S, Priyanka D, LaBranche CC, Sri Teja M, Montefiori DC, Pal R, Mahalingam S, Kalyanaraman VS. Antigenicity and immunogenicity of a trimeric envelope protein from an Indian clade C HIV-1 isolate. J Biol Chem 2015; 290:9195-208. [PMID: 25691567 PMCID: PMC4423705 DOI: 10.1074/jbc.m114.621185] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 02/09/2015] [Indexed: 11/06/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) isolates from India mainly belong to clade C and are quite distinct from clade C isolates from Africa in terms of their phylogenetic makeup, serotype, and sensitivity to known human broadly neutralizing monoclonal antibodies. Because many of these properties are associated with the envelope proteins of HIV-1, it is of interest to study the envelope proteins of Indian clade C isolates as part of the ongoing efforts to develop a vaccine against HIV-1. To this end, we purified trimeric uncleaved gp145 of a CCR5 tropic Indian clade C HIV-1 (93IN101) from the conditioned medium of 293 cells. The purified protein was shown to be properly folded with stable structure by circular dichroism. Conformational integrity was further demonstrated by its high affinity binding to soluble CD4, CD4 binding site antibodies such as b12 and VRC01, quaternary epitope-specific antibody PG9, and CD4-induced epitope-specific antibody 17b. Sera from rabbits immunized with gp145 elicited high titer antibodies to various domains of gp120 and neutralized a broad spectrum of clade B and clade C HIV-1 isolates. Similar to other clade B and clade C envelope immunogens, most of the Tier 1 neutralizing activity could be absorbed with the V3-specific peptide. Subsequent boosting of these rabbits with a clade B HIV-1 Bal gp145 resulted in an expanded breadth of neutralization of HIV-1 isolates. The present study strongly supports the inclusion of envelopes from Indian isolates in a future mixture of HIV-1 vaccines.
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Affiliation(s)
- Rangasamy Sneha Priya
- From the Laboratory of Molecular Virology and Cell Biology, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Menon Veena
- Advanced Bioscience Laboratories Inc., Rockville, Maryland 20850, and
| | - Irene Kalisz
- Advanced Bioscience Laboratories Inc., Rockville, Maryland 20850, and
| | - Stephen Whitney
- Advanced Bioscience Laboratories Inc., Rockville, Maryland 20850, and
| | | | - Celia C LaBranche
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | - Mullapudi Sri Teja
- From the Laboratory of Molecular Virology and Cell Biology, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - David C Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | - Ranajit Pal
- Advanced Bioscience Laboratories Inc., Rockville, Maryland 20850, and
| | - Sundarasamy Mahalingam
- From the Laboratory of Molecular Virology and Cell Biology, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India,
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Subtype-specific analysis of the K65R substitution in HIV-1 that confers hypersusceptibility to a novel nucleotide-competing reverse transcriptase inhibitor. Antimicrob Agents Chemother 2015; 59:3189-96. [PMID: 25779585 DOI: 10.1128/aac.00315-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 03/11/2015] [Indexed: 12/20/2022] Open
Abstract
Compound A is a novel nucleotide-competing HIV-1 reverse transcriptase (RT) inhibitor (NcRTI) that selects for a unique W153L substitution that confers hypersusceptibility to tenofovir, while the K65R substitution in RT confers resistance against tenofovir and enhances susceptibility to NcRTIs. Although the K65R substitution is more common in subtype C viruses, the impact of subtype variability on NcRTI susceptibility has not been studied. In the present study, we performed experiments with compound A by using purified recombinant RT enzymes and viruses of subtypes B and C and circulating recombinant form CRF_A/G. We confirmed the hypersusceptibility of K65R substitution-containing RTs to compound A for subtype C, CRF_A/G, and subtype B. Steady-state kinetic analysis showed that K65R RTs enhanced the susceptibility to compound A by increasing binding of the inhibitor to the nucleotide binding site of RT in a subtype-independent manner, without significantly discriminating against the natural nucleotide substrate. These data highlight the potential utility of NcRTIs, such as compound A, for treatment of infections with K65R substitution-containing viruses, regardless of HIV-1 subtype.
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21
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Quan Y, Xu H, Kramer VG, Han Y, Sloan RD, Wainberg MA. Identification of an env-defective HIV-1 mutant capable of spontaneous reversion to a wild-type phenotype in certain T-cell lines. Virol J 2014; 11:177. [PMID: 25287969 PMCID: PMC4283149 DOI: 10.1186/1743-422x-11-177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 09/26/2014] [Indexed: 04/08/2023] Open
Abstract
Background Attempts to eradicate HIV from cellular reservoirs are vital but depend on a clear understanding of how viral variants are transmitted and survive in the different cell types that constitute such reservoirs. Mutations in the env gene of HIV may be able to exert a differential influence on viral transmission ability in regard to cell-free and cell-associated viral forms. Methods The ability of HIV containing an env G367R mutation in cell-free and cell-associated viruses to cause infection and to revert to wild-type was measured using several T cell lines. To determine factors that might potentially influence the reversion of G367R, we studied each of entry inhibitors, inhibitors of cellular endocytosis, and modulators of cell growth and activation. Results We demonstrate that an HIV-1 variant containing a G367R substitution within the CD4 binding site of gp120 was non-infectious as free virus in culture but was infectious when infected cells were co-cultured with certain T cell lines or when cells were transfected by a relevant proviral plasmid. Differences in viral infectivity by cell-associated G367R viruses were determined by the type of target cell employed, regardless which type of donor cell was used. Reversion was slowed or inhibited by entry inhibitors and by inhibitors of cellular endocytosis. Interleukin 2 was able to block G367R reversion in only one of the T cell lines studied but not in the other, while phorbol 12-myristate 13-acetate (PMA) inhibited G367R reversion in all the T cell lines. Conclusions Env-defective HIV may have a different phenotype as cell-free versus cell-associated virus. The persistence of defective forms can potentially lead to the emergence of virulent forms. The heterogeneity of cell types that constitute the HIV reservoir can contribute to viral variability, even among similar types of cells. This is the first demonstration of a mutation in the HIV envelope, i.e. G367R, that can compromise infection by cell-free virus but less severely by cell-associated virus and that does so in a cell type-dependent manner.
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Affiliation(s)
| | | | | | | | | | - Mark A Wainberg
- McGill University AIDS Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Cote Sainte Catherine, Montreal, QC H3T 1E2, Canada.
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22
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Scarborough RJ, Lévesque MV, Boudrias-Dalle E, Chute IC, Daniels SM, Ouellette RJ, Perreault JP, Gatignol A. A Conserved Target Site in HIV-1 Gag RNA is Accessible to Inhibition by Both an HDV Ribozyme and a Short Hairpin RNA. MOLECULAR THERAPY. NUCLEIC ACIDS 2014; 3:e178. [PMID: 25072692 PMCID: PMC4121520 DOI: 10.1038/mtna.2014.31] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 06/03/2014] [Indexed: 12/18/2022]
Abstract
Antisense-based molecules targeting HIV-1 RNA have the potential to be used as part of gene or drug therapy to treat HIV-1 infection. In this study, HIV-1 RNA was screened to identify more conserved and accessible target sites for ribozymes based on the hepatitis delta virus motif. Using a quantitative screen for effects on HIV-1 production, we identified a ribozyme targeting a highly conserved site in the Gag coding sequence with improved inhibitory potential compared to our previously described candidates targeting the overlapping Tat/Rev coding sequence. We also demonstrate that this target site is highly accessible to short hairpin directed RNA interference, suggesting that it may be available for the binding of antisense RNAs with different modes of action. We provide evidence that this target site is structurally conserved in diverse viral strains and that it is sufficiently different from the human transcriptome to limit off-target effects from antisense therapies. We also show that the modified hepatitis delta virus ribozyme is more sensitive to a mismatch in its target site compared to the short hairpin RNA. Overall, our results validate the potential of a new target site in HIV-1 RNA to be used for the development of antisense therapies.
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Affiliation(s)
- Robert J Scarborough
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | - Michel V Lévesque
- Département de Biochimie, RNA Group/Groupe ARN, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Etienne Boudrias-Dalle
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | - Ian C Chute
- Atlantic Cancer Research Institute, Moncton, New Brunswick, Canada
| | - Sylvanne M Daniels
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | | | - Jean-Pierre Perreault
- Département de Biochimie, RNA Group/Groupe ARN, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Anne Gatignol
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada [3] Department of Medicine, McGill University, Montréal, Québec, Canada
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23
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Quan Y, Xu H, Wainberg MA. Defective HIV-1 quasispecies in the form of multiply drug-resistant proviral DNA within cells can be rescued by superinfection with different subtype variants of HIV-1 and by HIV-2 and SIV. J Antimicrob Chemother 2013; 69:21-7. [PMID: 23963235 DOI: 10.1093/jac/dkt326] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES HIV-1 generates swarms of similar, but genetically distinct, variants termed quasispecies and many of these variants can be defective. A relevant question is whether such defective species can contribute to viral pathogenesis. Indeed, we previously reported that a presumed recombination of defective proviral DNA with other complementary defective proviral DNA or with wild-type viral DNA in the aftermath of superinfection could lead to the rescue of defective provirus and the production of replication-competent virus. We then wished to determine whether such rescue could be affected by viruses of different subtypes or even by other members of the retrovirus family. METHODS Here, we have used drug resistance mutations within the HIV genome as markers of potential recombination. RESULTS We show that a defective proviral DNA within cells can be rescued by the superinfection of MT2 cells by various subtypes of HIV-1, and by HIV-2 and simian immunodeficiency virus, but not by human T cell leukaemia virus type 1 or by human herpes virus-6. The drug-resistance phenotype of the rescued HIV was confirmed in a second round of infection. CONCLUSIONS Defective proviral HIV-1 can be rescued by the infection by different variants of HIV-1 and by several other retroviruses as well.
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Affiliation(s)
- Yudong Quan
- McGill University AIDS Centre, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, McGill University, Montréal, Québec, Canada
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24
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Rao VR, Neogi U, Talboom JS, Padilla L, Rahman M, Fritz-French C, Gonzalez-Ramirez S, Verma A, Wood C, Ruprecht RM, Ranga U, Azim T, Joska J, Eugenin E, Shet A, Bimonte-Nelson H, Tyor WR, Prasad VR. Clade C HIV-1 isolates circulating in Southern Africa exhibit a greater frequency of dicysteine motif-containing Tat variants than those in Southeast Asia and cause increased neurovirulence. Retrovirology 2013; 10:61. [PMID: 23758766 PMCID: PMC3686704 DOI: 10.1186/1742-4690-10-61] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 05/28/2013] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND HIV-1 Clade C (Subtype C; HIV-1C) is responsible for greater than 50% of infections worldwide. Unlike clade B HIV-1 (Subtype B; HIV-1B), which is known to cause HIV associated dementia (HAD) in approximately 15% to 30% of the infected individuals, HIV-1C has been linked with lower prevalence of HAD (0 to 6%) in India and Ethiopia. However, recent studies report a higher prevalence of HAD in South Africa, Zambia and Botswana, where HIV-1C infections predominate. Therefore, we examined whether Southern African HIV-1C is genetically distinct and investigated its neurovirulence. HIV-1 Tat protein is a viral determinant of neurocognitive dysfunction. Therefore, we focused our study on the variations seen in tat gene and its contribution to HIV associated neuropathogenesis. RESULTS A phylogenetic analysis of tat sequences of Southern African (South Africa and Zambia) HIV isolates with those from the geographically distant Southeast Asian (India and Bangladesh) isolates revealed that Southern African tat sequences are distinct from Southeast Asian isolates. The proportion of HIV - 1C variants with an intact dicysteine motif in Tat protein (C30C31) was significantly higher in the Southern African countries compared to Southeast Asia and broadly paralleled the high incidence of HAD in these countries. Neuropathogenic potential of a Southern African HIV-1C isolate (from Zambia; HIV-1C 1084i), a HIV-1C isolate (HIV-1 IndieC1) from Southeast Asia and a HIV-1B isolate (HIV-1 ADA) from the US were tested using in vitro assays to measure neurovirulence and a SCID mouse HIV encephalitis model to measure cognitive deficits. In vitro assays revealed that the Southern African isolate, HIV-1C 1084i exhibited increased monocyte chemotaxis and greater neurotoxicity compared to Southeast Asian HIV-1C. In neurocognitive tests, SCID mice injected with MDM infected with Southern African HIV-1C 1084i showed greater cognitive dysfunction similar to HIV-1B but much higher than those exposed to Southeast Asian HIV - 1C. CONCLUSIONS We report here, for the first time, that HIV-1C from Southern African countries is genetically distinct from Southeast Asian HIV-1C and that it exhibits a high frequency of variants with dicysteine motif in a key neurotoxic HIV protein, Tat. Our results indicate that Tat dicysteine motif determines neurovirulence. If confirmed in population studies, it may be possible to predict neurocognitive outcomes of individuals infected with HIV-1C by genotyping Tat.
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Affiliation(s)
- Vasudev R Rao
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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Koyama T, Sun B, Tokunaga K, Tatsumi M, Ishizaka Y. DNA damage enhances integration of HIV-1 into macrophages by overcoming integrase inhibition. Retrovirology 2013; 10:21. [PMID: 23432899 PMCID: PMC3605128 DOI: 10.1186/1742-4690-10-21] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 02/11/2013] [Indexed: 11/10/2022] Open
Abstract
Background The prevention of persistent human immunodeficiency virus type 1 (HIV-1) infection requires the clarification of the mode of viral transduction into resting macrophages. Recently, DNA double-strand breaks (DSBs) were shown to enhance infection by D64A virus, which has a defective integrase catalytic activity (IN-CA). However, the mechanism by which DSBs upregulate viral transduction was unclear. Here we analyzed the roles of DSBs during IN-CA–independent viral transduction into macrophages. Results We used cellular systems with rare-cutting endonucleases and found that D64A virus integrated efficiently into the sites of artificially induced DSBs. This IN-CA-independent viral transduction was blocked by an inhibitor of ataxia telangiectasia mutated protein (ATM) but was resistant to raltegravir (RAL), an inhibitor of integrase activity during strand transfer. Moreover, Vpr, an accessory gene product of HIV-1, induced DSBs in resting macrophages and significantly enhanced the rate of IN-CA-independent viral transduction into macrophages with concomitant production of secondary viruses. Conclusion DSBs contribute to the IN-CA–independent viral infection of macrophages, which is resistant to RAL. Thus, the ATM-dependent cellular pathway and Vpr-induced DNA damage are novel targets for preventing persistent HIV-1 infection.
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Affiliation(s)
- Takayoshi Koyama
- Department of Intractable Diseases, National Center for Global Health and Medicine, 1-21-1 Toyama, 162-8655, Shinjuku-ku, Tokyo, Japan
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Sundaramurthi JC, Ramanathan V, Hanna LE. HLA-B*27:05-specific cytotoxic T lymphocyte epitopes in Indian HIV type 1C. AIDS Res Hum Retroviruses 2013; 29:47-53. [PMID: 22924625 DOI: 10.1089/aid.2011.0374] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HLA-B*27:05 is one of the widely reported alleles associated with resistance to HIV, while HLA-A24, HLA-B7, HLA-B*07:02, HLA-B*35:01, HLA-B*53:01, and HLA-B40 are reported to be associated with susceptibility to HIV. Using a bioinformatics approach we attempted to predict potential HLA-B*27:05-specific HIV-1C epitopes that do not bind to susceptibility-associated HLA alleles based on our hypothesis that such epitopes have a greater probability of eliciting a protective immune response in the host. A consensus sequence was built for all proteins of Indian clade C virus. Epitopes specific to HLA-B*27:05 were predicted from the consensus sequence using two different bioinformatics methods to enhance the accuracy of the prediction. Epitopes that were also predicted to bind to any of the susceptibility-associated HLA alleles were excluded from the list. The short-listed epitopes were modeled using MODPROPEP to refine the prediction. Fourteen peptides were identified as epitopes by both sequence-based methods and were found to interact strongly with HLA-B*27:05 by molecular modeling studies. Five of the 14 epitopes were previously reported as immunogenic by other researchers, while the remaining nine are novel. The 14 epitopes have been repeatedly identified by three different methods indicating their potential as useful candidates for an effective HIV vaccine.
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Affiliation(s)
- Jagadish Chandrabose Sundaramurthi
- Division of Biomedical Informatics, Department of Clinical Research, National Institute for Research in Tuberculosis (Formerly Tuberculosis Research Centre) (ICMR), Chennai, Tamil Nadu, India
| | - V.D. Ramanathan
- Department of Pathology, National Institute for Research in Tuberculosis (Formerly Tuberculosis Research Centre) (ICMR), Chennai, Tamil Nadu, India
| | - Luke Elizabeth Hanna
- Division of HIV/AIDS, Department of Clinical Research, National Institute for Research in Tuberculosis (Formerly Tuberculosis Research Centre) (ICMR), Chennai, Tamil Nadu, India
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27
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Wang Z, Hong K, Zhang J, Zhang L, Li D, Ren L, Liang H, Shao Y. Construction and characterization of highly infectious full-length molecular clones of a HIV-1 CRF07_BC isolate from Xinjiang, China. PLoS One 2013; 8:e79177. [PMID: 24324545 PMCID: PMC3850540 DOI: 10.1371/journal.pone.0079177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 09/22/2013] [Indexed: 12/15/2022] Open
Abstract
Among the various subtypes of the M group of human immunodeficiency virus type 1 (HIV-1), clade CRF07_BC is the most prevalent in China. To date, no strong replicable CRF07_BC infectious clone has been constructed. Here we report on the construction and characterization of highly replicable infectious molecular clones from the isolate XJDC6291 of this HIV-1 subtype. Four full-length clones pXJDC2-7, pXJDC3-7, pXJDC2-6 and pXJDC3-6 were successfully produced, but only pXJDC2-7 presented detectable infectivity and replication capability. To improve the replication capability of pXJDC2-7, a 4.8 kb region spanning from the pol Integrase to nef gene of the clone was replaced by PCR products of the corresponding fragments from the original isolate XJDC6291, which produced two clones pXJDC13 and pXJDC17 that exhibited strong replication capability. The viral stocks obtained by pXJDC-13 and pXJDC-17 transfection into 293T cells replicated efficiently in human PBMCs, human primary CD4(+) T cells and displayed CCR5 tropism. Sequence alignment between pXJDC13, pXJDC17 and pXJDC2-7 suggested that polymorphisms in the V1V2 region may influence infectivity, and reverse genetic experiment showed that V1V2 polymorphisms may influence the infectivity of the clones but did not affect the replication capability at a significant level. pXJDC13 and pXJDC17 displayed strong replication capability and are the first full-length infectious clones of HIV-1 CRF07_BC clade in the world. The availability of CRF07_BC infectious clones provides a useful tool for a wide range of studies, including antiretroviral drug and vaccine research as related to this HIV subtype.
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Affiliation(s)
- Zheng Wang
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Kunxue Hong
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Jing Zhang
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Lei Zhang
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Dan Li
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Li Ren
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Hua Liang
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
| | - Yiming Shao
- State Key Laboratory for Infectious Disease Prevention and Control, Division of Research of Virology and Immunology, National Center for AIDS/STD Control and Prevention, China CDC, Beijing, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, China
- * E-mail:
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Construction of a high titer infectious HIV-1 subtype C proviral clone from South Africa. Viruses 2012; 4:1830-43. [PMID: 23170185 PMCID: PMC3499832 DOI: 10.3390/v4091830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 09/13/2012] [Accepted: 09/13/2012] [Indexed: 12/13/2022] Open
Abstract
The Human Immunodeficiency Virus type 1 (HIV-1) subtype C is currently the predominant subtype worldwide. Cell culture studies of Sub-Saharan African subtype C proviral plasmids are hampered by the low replication capacity of the resulting viruses, although viral loads in subtype C infected patients are as high as those from patients with subtype B. Here, we describe the sequencing and construction of a new HIV-1 subtype C proviral clone (pZAC), replicating more than one order of magnitude better than the previous subtype C plasmids. We identify the env-region for being the determinant for the higher viral titers and the pZAC Env to be M-tropic. This higher replication capacity does not lead to a higher cytotoxicity compared to previously described subtype C viruses. In addition, the pZAC Vpu is also shown to be able to down-regulate CD4, but fails to fully counteract CD317.
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Patil A, Bhattacharya J. Natural deletion of L35Y36 in p6 gag eliminate LYPXnL/ALIX auxiliary virus release pathway in HIV-1 subtype C. Virus Res 2012; 170:154-8. [PMID: 22981647 DOI: 10.1016/j.virusres.2012.08.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 08/28/2012] [Accepted: 08/29/2012] [Indexed: 01/17/2023]
Abstract
Natural loss of L35Y36 residues in ALIX binding site of HIV-1 subtype C was found to prevent the p6 gag-ALIX interaction. Over expression of ALIX 364-716 (V-domain) unlike pNL4.3 (subtype B), also did not inhibit the release of chimeric pNL4.3 expressing subtype C p6 late domain. Loss of V domain binding consequently affected the ALIX mediated particle release in the absence of PTAP/TSG101 pathway. Our data indicated absence of LYPXnL/ALIX pathway in HIV-1 subtype C.
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Affiliation(s)
- Ajit Patil
- Department of Molecular Virology, National AIDS Research Institute, G-73 MIDC, Bhosari, Pune, India
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30
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HIV gp120 H375 is unique to HIV-1 subtype CRF01_AE and confers strong resistance to the entry inhibitor BMS-599793, a candidate microbicide drug. Antimicrob Agents Chemother 2012; 56:4257-67. [PMID: 22615295 DOI: 10.1128/aac.00639-12] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
BMS-599793 is a small molecule entry inhibitor that binds to human immunodeficiency virus type 1 (HIV-1) gp120, resulting in the inhibition of CD4-dependent entry into cells. Since BMS-599793 is currently considered a candidate microbicide drug, we evaluated its efficacy against a number of primary patient HIV isolates from different subtypes and circulating recombinant forms (CRFs) and showed that activity varied between ∼3 ρM and 7 μM at 50% effective concentrations (EC(50)s). Interestingly, CRF01_AE HIV-1 isolates consistently demonstrated natural resistance against this compound. Genotypic analysis of >1,600 sequences (Los Alamos HIV sequence database) indicated that a single amino acid polymorphism in Env, H375, may account for the observed BMS-599793 resistance in CRF01_AE HIV-1. Results of site-directed mutagenesis experiments confirmed this hypothesis, and in silico drug docking simulations identified a drug resistance mechanism at the molecular level. In addition, CRF01_AE viruses were shown to be resistant to multiple broadly neutralizing monoclonal antibodies. Thus, our results not only provide insight into how Env polymorphisms may contribute to entry inhibitor resistance but also may help to elucidate how HIV can evade some broadly neutralizing antibodies. Furthermore, the high frequency of H375 in CRF01_AE HIV-1, and its apparent nonoccurrence in other subtypes, could serve as a means for rapid identification of CRF01_AE infections.
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Zhang Q, Zhang X, Wu H, Seto D, Zhang HJ, Chen Z, Wan C, Zheng BJ. Parental LTRs are important in a construct of a stable and efficient replication-competent infectious molecular clone of HIV-1 CRF08_BC. PLoS One 2012; 7:e31233. [PMID: 22363589 PMCID: PMC3281951 DOI: 10.1371/journal.pone.0031233] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 01/04/2012] [Indexed: 12/17/2022] Open
Abstract
Circulating recombinant forms (CRFs) of HIV-1 have been identified in southern China in recent years. CRF08_BC is one of the most predominant subtypes circulating in China. In order to study HIV subtype biology and to provide a tool for biotechnological applications, the first full-length replication-competent infectious molecular clone harboring CRF08_BC is reported. The construction of this clone pBRGX indicates that a moderate-copy number vector is required for its amplification in E. coli. In addition, it is shown that the parental CRF08_BC LTRs are important for generating this efficient replication-competent infectious clone. These observations may aid in the construction of infectious clones from other subtypes. Both the pBRGX-derived virus and its parental isolate contain CCR5 tropism. Their full-length genomes were also sequenced, analyzed, compared and deposited in GenBank (JF719819 and JF719818, respectively). The availability of pBRGX as the first replication-competent molecular clone of CRF08_BC provides a useful tool for a wide range of studies of this newly emergent HIV subtype, including the development of HIV vaccine candidates, antiviral drug screening and drug resistance analysis.
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Affiliation(s)
- Qiwei Zhang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- Department of Microbiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, China
- * E-mail: (QZ); (BJZ)
| | - Xiaomin Zhang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Hao Wu
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Donald Seto
- Bioinformatics and Computational Biology, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Hao-Jie Zhang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Zhiwei Chen
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- AIDS Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Chengsong Wan
- Department of Microbiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, China
| | - Bo-Jian Zheng
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- * E-mail: (QZ); (BJZ)
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32
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Diagnosis of HIV-1 infection by near-infrared spectroscopy: Analysis using molecular clones of various HIV-1 subtypes. Clin Chim Acta 2012; 413:467-72. [DOI: 10.1016/j.cca.2011.10.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 10/31/2011] [Accepted: 10/31/2011] [Indexed: 11/19/2022]
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Toda T, Kuwahara K, Kondo N, Matsuda Z, Maeda Y, Maeda K, Sakaguchi N. Dynamic appearance of antigenic epitopes effective for viral neutralization during membrane fusion initiated by interactions between HIV-1 envelope proteins and CD4/CXCR4. Immunobiology 2011; 217:864-72. [PMID: 22226668 DOI: 10.1016/j.imbio.2011.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2011] [Revised: 12/15/2011] [Accepted: 12/16/2011] [Indexed: 11/19/2022]
Abstract
HIV-1 entry into cells is mediated by interactions between the envelope (Env) gp120 and gp41 proteins with CD4 and chemokine receptors via an intermediate called the viral fusion complex (vFC). Here, mAbs were used to find the dynamic changes in expression of antigenic epitopes during vFC formation. A CD4-specific mAb (R275) and anti-vFC mAbs, designated F12-1, F13-6 and F18-4 that recognize the epitopes only appeared by the co-culture of env-transfected 293FT and CD4-transfected 293 cells, were developed by immunizing ganp-gene transgenic mice with an vFC-like structure formed by the same co-culture. The epitopes recognized by the mAbs appeared at different time points during vFC formation: F18-4 appeared first, followed by F13-6, and finally F12-1. The anti-vFC mAbs had little effect on vFC formation or virus neutralization; however, interestingly F12-1 and F18-4 increased exposure of the OKT4-epitope on the domain 3 in the extracellular region of CD4. R275, which recognizes the epitope closely associated with the OKT4-determinant on the domain 3, showed the marked inhibition of vFC formation and viral neutralization activity. The Ab binding to the epitopes appeared during viral membrane fusion might reinforce the appearance of the target epitopes for effective neutralization activity.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/metabolism
- CD4 Antigens/immunology
- CD4 Antigens/metabolism
- Cell Line
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Gene Order
- Gene Targeting
- HIV Antibodies/immunology
- HIV Antibodies/metabolism
- HIV-1/immunology
- Humans
- Immunoglobulin Fc Fragments/immunology
- Immunoglobulin Fc Fragments/metabolism
- Mice
- Mice, Transgenic
- Neutralization Tests
- Protein Binding
- Receptors, CXCR4/immunology
- Receptors, CXCR4/metabolism
- Virus Internalization
- env Gene Products, Human Immunodeficiency Virus/chemistry
- env Gene Products, Human Immunodeficiency Virus/immunology
- env Gene Products, Human Immunodeficiency Virus/metabolism
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Affiliation(s)
- Teppei Toda
- Department of Immunology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan
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Biswas N, Wang T, Ding M, Tumne A, Chen Y, Wang Q, Gupta P. ADAR1 is a novel multi targeted anti-HIV-1 cellular protein. Virology 2011; 422:265-77. [PMID: 22104209 DOI: 10.1016/j.virol.2011.10.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/29/2011] [Accepted: 10/16/2011] [Indexed: 11/29/2022]
Abstract
We examined the antiviral activity of ADAR1 against HIV-1. Our results indicated that ADAR1 in a transfection system inhibited production of viral proteins and infectious HIV-1 in various cell lines including 293T, HeLa, Jurkat T and primary CD4+ T cells, and was active against a number of X4 and R5 HIV-1 of different clades. Further analysis showed that ADAR1 inhibited viral protein synthesis without any effect on viral RNA synthesis. Mutational analysis showed that ADAR1 introduced most of the A-to-G mutations in the rev RNA, in the region of RNA encoding for Rev Response Element (RRE) binding domain and in env RNA. These mutations inhibited the binding of rev to the RRE and inhibited transport of primary transcripts like gag, pol and env from nucleus to cytoplasm resulting in inhibition of viral protein synthesis without any effect on viral RNA synthesis. Furthermore, ADAR1 induced mutations in the env gene inhibited viral infectivity.
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Affiliation(s)
- Nabanita Biswas
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Synergy against drug-resistant HIV-1 with the microbicide antiretrovirals, dapivirine and tenofovir, in combination. AIDS 2011; 25:1585-94. [PMID: 21633286 DOI: 10.1097/qad.0b013e3283491f89] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To evaluate the candidate antiretroviral microbicide compounds, dapivirine (DAP) and tenofovir (TFV), alone and in combination against the transmission of wild-type and nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant HIV-1 from different subtypes. DESIGN AND METHODS We determined single-drug efficacy of the RTIs, DAP and TFV, against subtype B and non-B wild-type and NNRTI-resistant HIV-1 in vitro. To assess breadth of activity, compounds were tested alone and in combination against wild-type and NNRTI-resistant subtype C primary HIV-1 isolates and complimentary clonal HIV-1 from subtypes B, C and CRF02_AG to control for viral variation. Early infection was quantified by counting light units emitted from TZM-bl cells less than 48-h postinfection. Combination ratios were based on drug inhibitory concentrations (IC(50)s) and combined effects were determined by calculating combination indices. RESULTS Both candidate microbicide antiretrovirals demonstrated potent anti-NNRTI-resistant HIV-1 activity in vitro, albeit the combination protected better than the single-drug treatments. Of particular interest, the DAP with TFV combination exhibited synergy (50% combination index, CI(50) = 0.567) against subtype C NNRTI-resistant HIV-1, whereas additivity (CI(50) = 0.987) was observed against the wild-type counterpart from the same patient. The effect was not compounded by the presence of subdominant viral fractions, as experiments using complimentary clonal subtype C wild-type (CI(50) = 0.968) and NNRTI-resistant (CI(50) = 0.672) HIV-1, in lieu of the patient quasispecies, gave similar results. CONCLUSION This study supports the notion that antiretroviral drug combinations may retain antiviral activity against some drug-resistant HIV-1 despite subtype classification and quasispecies diversity.
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Inhibition of β-TrcP-dependent ubiquitination of p53 by HIV-1 Vpu promotes p53-mediated apoptosis in human T cells. Blood 2011; 117:6600-7. [PMID: 21521785 DOI: 10.1182/blood-2011-01-333427] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
HIV-1 viral protein U (Vpu) is involved in ubiquitination and degradation of BM stromal cell Ag 2 and surface receptor CD4 through their recruitment to SCF(β-TrcP) (Skp1/Cul1/F-box) ubiquitin ligase (SCF) complex. Here, we show that specific interaction of wild-type Vpu protein with SCF complex leads to inhibition of ubiquitination and proteasomal degradation of p53 protein in a β-TrcP-dependent manner. Successful interaction of SCF(β-TrcP) complex with β-TrcP binding motif (DS(52)GNES(56)) present in Vpu is essential because mutant Vpu possessing specific alanine substitutions (DA(52)GNEA(56)) in the β-TrcP binding motif not only failed to stabilize p53 protein but was also unable to inhibit ubiquitination of p53 protein. Furthermore, Vpu competes efficiently with the interaction of p53 protein with the β-TrcP subunit of the SCF complex and inhibits subsequent ubiquitination of p53 proteins in a dose-dependent manner. We also observed potent apoptotic activity in a p53 null cell line (H-1299) that was cotransfected with p53 and Vpu-expressing plasmids. Furthermore, MOLT-3 (human T-lymphoblast) cells when infected with vesicular stomatitis virus glycoprotein-pseudotypic HIV-1 possessing wild-type vpu gene exhibited maximum activation of p53/Bax proteins and p53-mediated cell death. These findings establish a novel function of Vpu in modulating the stability of p53 protein that correlates positively with apoptosis during late stages of HIV-1 infection.
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Bala M, Arias JF, Deb M, Ikuta K. Immunofluorescence assay in India for confirmation of HIV-1 infection using a T-cell line infected with defective HIV-1. Int J Infect Dis 2010; 14:e1093-8. [PMID: 20952236 DOI: 10.1016/j.ijid.2010.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 07/22/2010] [Accepted: 08/16/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In India, the enzyme immunoassay (EIA)/rapid test is used for screening and confirmatory antibody testing of HIV infection, and all HIV reactive samples are further confirmed by two other rapid tests working on different principles; however, Western blotting (WB) and immunofluorescence (IF) assays are not routinely performed in this country. METHODS A total of 2104 sera from Indian subjects were tested for the presence of HIV-1 antibody using EIA/rapid tests, according to the guidelines of the National AIDS Control Organization of India, and were also subjected to IF test using L-2 cells persistently infected with defective HIV-1. WB and a nested reverse transcriptase polymerase chain reaction (RT-PCR) were performed on discrepant samples. RESULTS IF results were 100% concordant with EIA/rapid tests for 212 HIV-1-positive samples and 1889 HIV-1-negative samples. Interestingly, three (0.14%) samples negative by EIA/rapid tests were weakly or moderately positive (1+/2+) by IF test. All three of these samples were confirmed to be negative by WB (reactive with Gag/Pol, but not with Env), but positive by RT-PCR with primers targeting the C2-V5 fragment of the env gene. These three samples were from individuals who voluntarily reported for HIV testing because of high-risk practices, and they may have been at an early stage of HIV infection. CONCLUSIONS These results confirm that the IF test using L-2 cells is a sensitive and specific alternative method for confirmation of HIV-1 infection and could be included in the diagnostic algorithm in reference laboratories in developing countries.
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Affiliation(s)
- Manju Bala
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamadaoka, Suita, Osaka 565-0871, Japan
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Construction and characterization of a full-length infectious clone from a fast-replicating, X4-tropic HIV-1 subtype B′ isolate. Arch Virol 2010; 155:1923-31. [DOI: 10.1007/s00705-010-0776-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 07/26/2010] [Indexed: 10/19/2022]
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Sakuragi JI, Sakuragi S, Ohishi M, Shioda T. Direct correlation between genome dimerization and recombination efficiency of HIV-1. Microbes Infect 2010; 12:1002-11. [PMID: 20637891 DOI: 10.1016/j.micinf.2010.06.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 06/24/2010] [Accepted: 06/26/2010] [Indexed: 11/19/2022]
Abstract
More than ten subtypes of Human immunodeficiency virus type 1 (HIV-1) have been identified, and many inter-subtype recombinant viruses have been isolated. The genome of HIV-1 is a single-stranded positive sense RNA, and is always found as dimers in virus particles. Frequent recombination between two genomes during reverse transcription is often observed and thus reasonable to assume that genome dimerization controls viral genomic recombination. Recently, several reports indicated in vitro/in vivo data to support this idea. In the study reported here, in an attempt to show a comprehensive evidence, we compared the efficiency of various inter-subtype dimerization and recombination and detected a near-complete correlation of the two functions. This suggests that genome dimerization controls recombination and plays an important role in promoting the genetic diversity of HIV-1 in general. We also investigated various inter-subtype hetero-dimerization within HIV-1 virions, and found that the dimer initiation site is a major, but not the sole determinant of dimerization (and recombination) efficiency.
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Affiliation(s)
- Jun-ichi Sakuragi
- Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita City, Osaka 565-0871, Japan.
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HIV-1 protease codon 36 polymorphisms and differential development of resistance to nelfinavir, lopinavir, and atazanavir in different HIV-1 subtypes. Antimicrob Agents Chemother 2010; 54:2878-85. [PMID: 20404123 DOI: 10.1128/aac.01828-09] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The amino acid at position 36 of the HIV-1 protease differs among various viral subtypes, in that methionine is usually found in subtype B viruses but isoleucine is common in other subtypes. This polymorphism is associated with higher rates of treatment failure involving protease inhibitors (PIs) in non-subtype B-infected patients. To investigate this, we generated genetically homogeneous wild-type viruses from subtype B, subtype C, and CRF02_AG full-length molecular clones and showed that subtype C and CRF02_AG I36 viruses exhibited higher levels of resistance to various PIs than their respective M36 counterparts, while the opposite was observed for subtype B viruses. Selections for resistance with each variant were performed with nelfinavir (NFV), lopinavir (LPV), and atazanavir (ATV). Sequence analysis of the protease gene at week 35 revealed that the major NFV resistance mutation D30N emerged in NFV-selected subtype B viruses and in I36 subtype C viruses, despite polymorphic variation. A unique mutational pattern developed in subtype C M36 viruses selected with NFV or ATV. The presence of I47A in LPV-selected I36 CRF02_AG virus conferred higher-level resistance than L76V in LPV-selected M36 CRF02_AG virus. Phenotypic analysis revealed a >1,000-fold increase in NFV resistance in I36 subtype C NFV-selected virus with no apparent impact on viral replication capacity. Thus, the position 36 polymorphism in the HIV-1 protease appears to have a differential effect on both drug susceptibility and the viral replication capacity, depending on both the viral subtype and the drug being evaluated.
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Tripathy MK, Mitra D. Differential modulation of mitochondrial OXPHOS system during HIV-1 induced T-cell apoptosis: up regulation of Complex-IV subunit COX-II and its possible implications. Apoptosis 2010; 15:28-40. [PMID: 19771519 DOI: 10.1007/s10495-009-0408-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Human Immunodeficiency Virus-1 (HIV-1) infection leads to CD4+ T cell depletion primarily by apoptosis employing both intrinsic and extrinsic pathways. Although extensive literature exists about the role of mitochondrial proteins in HIV induced T cell apoptosis, there is little understanding about the role of different components of mitochondrial oxidative phosphorylation (OXPHOS) system in apoptosis. The OXPHOS system comprises of five enzyme complexes (Complex I, II, III, IV, V), subunits of which have been implicated in various functions in addition to their primary role in energy generating process. Here using differential gene expression analysis, we report that Cytochrome Oxidase-II (COX-II), a subunit of Complex-IV is induced in HIV infected apoptotic T-cells. We also observe a temporal up regulation of this subunit across different T-cell lines and in human PBMCs. Further analysis indicates increase in expression of majority of Complex-IV subunits with concomitant increase in Complex-IV activity in HIV infected T cells. Silencing of COX-II expression leads to reduced apoptosis in infected T-cells, indicating its importance in apoptosis. Furthermore, our results also show that the activities of enzyme complexes I, II and III are decreased while those of Complex IV and V are increased at the time of acute infection and apoptosis. This differential regulation in activities of OXPHOS system complexes indicate a complex modulation of host cell energy generating system during HIV infection that ultimately leads to T cell apoptosis.
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Arias JF, Nishihara R, Bala M, Ikuta K. High systemic levels of interleukin-10, interleukin-22 and C-reactive protein in Indian patients are associated with low in vitro replication of HIV-1 subtype C viruses. Retrovirology 2010; 7:15. [PMID: 20211031 PMCID: PMC2841095 DOI: 10.1186/1742-4690-7-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 03/09/2010] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND HIV-1 subtype C (HIV-1C) accounts for almost 50% of all HIV-1 infections worldwide and predominates in countries with the highest case-loads globally. Functional studies suggest that HIV-1C is unique in its biological properties, and there are contradicting reports about its replicative characteristics. The present study was conducted to evaluate whether the host cytokine environment modulates the in vitro replication capacity of HIV-1C viruses. METHODS A small subset of HIV-1C isolates showing efficient replication in peripheral blood mononuclear cells (PBMC) is described, and the association of in vitro replication capacity with disease progression markers and the host cytokine response was evaluated. Viruses were isolated from patient samples, and the corresponding in vitro growth kinetics were determined by monitoring for p24 production. Genotype, phenotype and co-receptor usage were determined for all isolates, while clinical category, CD4 cell counts and viral loads were recorded for all patients. Plasmatic concentrations of cytokines and, acute-phase response, and microbial translocation markers were determined; and the effect of cytokine treatment on in vitro replication rates was also measured. RESULTS We identified a small number of viral isolates showing high in vitro replication capacity in healthy-donor PBMC. HIV-1C usage of CXCR4 co-receptor was rare; therefore, it did not account for the differences in replication potential observed. There was also no correlation between the in vitro replication capacity of HIV-1C isolates and patients' disease status. Efficient virus growth was significantly associated with low interleukin-10 (IL-10), interleukin-22 (IL-22), and C-reactive protein (CRP) levels in plasma (p < .0001). In vitro, pretreatment of virus cultures with IL-10 and CRP resulted in a significant reduction of virus production, whereas IL-22, which lacks action on immune cells appears to mediate its anti-HIV effect through interaction with both IL-10 and CRP, and its own protective effect on mucosal membranes. CONCLUSIONS These results indicate that high systemic levels of IL-10, CRP and IL-22 in HIV-1C-infected Indian patients are associated with low viral replication in vitro, and that the former two have direct inhibitory effects whereas the latter acts through downstream mechanisms that remain uncertain.
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Affiliation(s)
- Juan F Arias
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
- Viral Emergent Diseases Research Group (VIREM), Universidad del Valle, Cali, Colombia
| | - Reiko Nishihara
- Department of Health Promotion Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Manju Bala
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
- Regional STD Teaching, Training and Research Center, VM Medical College & Safdarjang Hospital, New Delhi, India
| | - Kazuyoshi Ikuta
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
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Kitagawa Y, Maeda-Sato M, Tanaka K, Tobiume M, Sawa H, Hasegawa H, Kojima A, Hall WW, Kurata T, Sata T, Takahashi H. Covalent bonded Gag multimers in human immunodeficiency virus type-1 particles. Microbiol Immunol 2009; 53:609-20. [PMID: 19903261 DOI: 10.1111/j.1348-0421.2009.00164.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The oligomerization of HIV-1 Gag and Gag-Pol proteins, which are assembled at the plasma membrane, leads to viral budding. The budding generally places the viral components under non-reducing conditions. Here the effects of non-reducing conditions on Gag structures and viral RNA protection were examined. Using different reducing conditions and SDS-PAGE, it was shown that oligomerized Gag possesses intermolecular covalent bonds under non-reducing conditions. In addition, it was demonstrated that the mature viral core contains a large amount of covalent bonded Gag multimers, as does the immature core. Viral genomic RNA becomes sensitive to ribonuclease in reducing conditions. These results suggest that, under non-reducing conditions, covalent bonded Gag multimers are formed within the viral particles and play a role in protection of the viral genome.
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Affiliation(s)
- Yoshinori Kitagawa
- Department of Pathology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
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HIV-1 clade C env clones obtained from an Indian patient exhibiting expanded coreceptor tropism are presented with naturally occurring unusual amino acid substitutions in V3 loop. Virus Res 2009; 144:306-14. [PMID: 19409946 DOI: 10.1016/j.virusres.2009.04.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 04/17/2009] [Indexed: 11/20/2022]
Abstract
HIV-1 subtype C is predominantly circulating in India and has been reported to be strictly CCR5 tropic irrespective of disease stages. In the present study, we examined env clones obtained from a late stage Indian patient with a history of multiple sexual partners and opportunistic infections for coreceptor usage and V3 loop sequence. The env clones were found to exploit several coreceptors in addition to CCR5 in a cell-associated and cell-free manner. Analysis of V3 loop sequence revealed that the NARI-VB105 env clones were presented with unique amino acid substitutions with GPGR motif, atypical of clade C envelope. Further genetic analysis showed the V3 sequences albeit belonging to subtype C; however clustered distinctly to that of other clade C envelopes originated in different geographical regions. Modelling data revealed that NARI-VB105 V3 loop contained several basic residues giving rise a high net positive charge of +8 to these envelopes.
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Estimation of the predictive role of plasma viral load on CD4 decline in HIV-1 subtype C-infected subjects in India. J Acquir Immune Defic Syndr 2009; 50:119-25. [PMID: 19131898 DOI: 10.1097/qai.0b013e3181911991] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Plasma viral load has been shown to be a meaningful prognostic marker for disease progression in untreated, HIV-1 subtype B-infected subjects in United States and Western Europe and therefore used as a prognostic marker for disease progression. Because of high expenses of commercially available viral load assays, the role of viral load in disease progression has not been evaluated in HIV-1 subtype C-infected patients in India. METHODS We developed an inexpensive real-time reverse transcriptase-polymerase chain reaction assay to quantify viral load in plasma of HIV-1 subtype C-infected subjects from India and used it in a longitudinal analysis of viral load and CD4 cell number in HIV-infected subjects from Calcutta, India. RESULTS The real-time reverse transcriptase-polymerase chain reaction assay can quantify plasma viral load with a linear range of detection from 10 to 10 HIV-1 RNA copies per input. Longitudinal analysis of viral load in a cohort of 39 subjects over an average period of approximately 3 years indicates that 1-log increase in HIV-1 RNA level was associated with a decline of 67 CD4 cell count. Furthermore, HIV-1 RNA level between 500 and 50,000 copies per milliliter would predict a 12.9% decrease in CD4 cell count per year, whereas HIV-1 RNA levels above 50,000 copies HIV-1 RNA per milliliter would predict a 25.3% decrease in CD4 cells per year. In addition, we estimated that the mean incubation period of disease development, as defined by the loss of CD4 below 200, is 8.2 years. CONCLUSION Our report on the level of viral load on predicting CD4 decline in Indian subjects with HIV-1 provides an additional important tool to the physicians for treating and planning a therapeutic strategy to control HIV-1 infection in India.
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Rodriguez MA, Ding M, Ratner D, Chen Y, Tripathy SP, Kulkarni SS, Chatterjee R, Tarwater PM, Gupta P. High replication fitness and transmission efficiency of HIV-1 subtype C from India: Implications for subtype C predominance. Virology 2009; 385:416-24. [PMID: 19157481 DOI: 10.1016/j.virol.2008.12.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 10/30/2008] [Accepted: 12/17/2008] [Indexed: 10/21/2022]
Abstract
HIV-1 subtype C has been the predominant subtype throughout the course of the HIV-1 epidemic in India regardless of the geographic region of the country. In an effort to understand the mechanism of subtype C predominance in this country, we have investigated the in vitro replication fitness and transmission efficiency of HIV-1 subtypes A and C from India. Using a dual infection growth competition assay, we found that primary HIV-1 subtype C isolates had higher overall relative fitness in PBMC than subtype A primary isolates. Moreover, in an ex vivo cervical tissue derived organ culture, subtype C isolates displayed higher transmission efficiency across cervical mucosa than subtype A isolates. We found that higher fitness of subtype C was not due to a trans effect exerted by subtype C infected PBMC. A half genome A/C recombinant clone in which the 3' half of the viral genome of subtype A was replaced with the corresponding subtype C3' half, had similar replicative fitness as the parental subtype A. These results suggest that the higher replication fitness and transmission efficiency of subtype C virus compared to subtype A virus from India is most probably not due to the envelope gene alone and may be due to genes present within the 5' half of the viral genome or to a more complex interaction between the genes located within the two halves of the viral genome. These data provide a model to explain the asymmetric distribution of subtype C over other subtypes in India.
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Affiliation(s)
- Milka A Rodriguez
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, 426 Parran Hall, GSPH, 130 DeSoto Street, Pittsburgh, PA 15261, USA
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Abstract
Human immunodeficiency virus (HIV)-associated dementia (HAD) is common among clade B HIV-infected individuals, but less common and less severe among individuals infected with clade C HIV-1, suggesting clade-specific differences in neuropathogenicity. Although differences in neuropathogenicity have been investigated in vitro using viral proteins responsible for HAD, to date there are no virological studies using animal models to address this issue. Therefore, we investigated neuropathogenesis induced by HIV-1 clades using the severe combined immune deficiency (SCID) mouse HIV encephalitis model, which involves intracranial injection of macrophages infected with representative clade B (HIV-1(ADA)) or clade C (HIV-1(Indie-C1)) HIV-1 isolates into SCID mice. In cognitive tests, mice exposed to similar inputs of HIV-1 clade C made fewer memory errors than those exposed to HIV-1 clade B. Histopathological analysis of mice exposed to clade B exhibited greater astrogliosis and increased loss of neuronal network integrity. In vitro experiments revealed differences in a key characteristic of HIV-1 that influences HAD, increased monocyte infiltration. HIV-1(Indie-C1)-infected macrophages recruited monocytes poorly in vitro compared with HIV-1(ADA)-infected macrophages. Monocyte recruitment was HIV-1 Tat and CCL2 dependent. This is the first demonstration, ever since HIV neuropathogenesis was first recognized, that viral genetic differences between clades can affect disease severity and that such studies help identify key players in neuropathogenesis by HIV-1.
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Swaminathan S, Hanna LE, Sundaramurthi JC, Leonard A, Angayarkanni B, Francis AC, Lakshmi S, Nayak K. Prevalence and pattern of cross-reacting antibodies to HIV in patients with tuberculosis. AIDS Res Hum Retroviruses 2008; 24:941-6. [PMID: 18593340 DOI: 10.1089/aid.2007.0211] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In many countries, HIV testing among tuberculosis (TB) patients is recommended so that both infections are appropriately treated. Cross-reacting antibodies to HIV antigens have been reported for several conditions, including TB, leprosy, malaria, and rheumatoid arthritis. To study the pattern and prevalence of cross-reacting antibodies to HIV antigens, we examined sera from 153 HIV-negative TB patients and 40 healthy individuals in Chennai, south India. We also studied the differences in cross-reactivity of various HIV antigens using two different Western blot kits. Of the 153 samples studied, 80 were tested using HIV Western blot and 73 were tested using INNOLIA. Most patients in the study had concordantly negative ELISA and rapid tests, and no subject had a positive Western blot. However, seven TB patients had antibodies that cross-reacted with HIV antigens, giving rise to an indeterminate result. While p51/55 was the most frequently recognized antigen in the Western blot assay, antibodies to sgp120 was most frequently identified in INNOLIA. Sequence similarities between the two organisms could be responsible for eliciting cross-reacting antibodies, since a few related epitopes were identified in HIV and Mycobacterium. These findings could have potential implications for the development of diagnostics and vaccines.
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Affiliation(s)
- Soumya Swaminathan
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
| | - Luke Elizabeth Hanna
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
| | | | - Antony Leonard
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
| | - B. Angayarkanni
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
| | | | - S. Lakshmi
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
| | - Kaustuv Nayak
- Division of HIV/AIDS, Tuberculosis Research Center, Indian Council of Medical Research, Chetput, Chennai, India
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Dash PK, Siddappa NB, Mangaiarkarasi A, Mahendarkar AV, Roshan P, Anand KK, Mahadevan A, Satishchandra P, Shankar SK, Prasad VR, Ranga U. Exceptional molecular and coreceptor-requirement properties of molecular clones isolated from an Human Immunodeficiency Virus Type-1 subtype C infection. Retrovirology 2008; 5:25. [PMID: 18328091 PMCID: PMC2292743 DOI: 10.1186/1742-4690-5-25] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Accepted: 03/07/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The pathogenic significance of coreceptor switch in the viral infection of HIV-1 is not completely understood. This situation is more complex in subtype C infection where coreceptor switch is either absent or extremely rare. To gain insights into the mechanisms that underlie coreceptor requirement of subtype C, we screened several primary viral isolates and identified a clinical sample that demonstrated a potential to grow on standard T-cell lines with no detectable CCR5 expression. The subject was diagnosed with HIV-1 associated dementia in the absence of opportunistic infections of the brain. To isolate molecular clones from this virus, we devised a novel strategy based on anchor primers that target a sequence in the reverse transcriptase, highly conserved among diverse subtypes of HIV-1. RESULTS Using this strategy, we isolated 8 full-length molecular clones from the donor. Two of the eight molecular clones, 03In94_D17 and 03In94_D24, (D17 and D24) generated replication-competent viruses. Phylogenetic analysis of the full-length viral sequences revealed that both clones were non-recombinant subtype C viruses. They contain intact open reading frames in all the viral proteins. Both the viral clones are endowed with several unique molecular and biological properties. The viral promoter of the clones is characterized by the presence of four NF-kB binding elements, a feature rarely seen in the subtype C HIV-1 LTR. Interestingly, we identified the coexistence of two different forms of Rev, a truncated form common to subtype C and a full-length form less common for this subtype, in both proviral and plasma virus compartments. An exceptional property of the viruses, atypical of subtype C, is their ability to use a wide range of coreceptors including CCR5, CXCR4, and several others tested. Sequence analysis of Env of D17 and D24 clones identified differences within the variable loops providing important clues for the expanded coreceptor use. The V1, V2 and V4 loops in both of the molecular clones are longer due to the insertion of several amino acid residues that generated potential N-linked glycosylation sites. CONCLUSION The exceptional biological and molecular properties of these clones make them invaluable tools to understand the unique pathogenic characteristics of subtype C.
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Affiliation(s)
- Prasanta K Dash
- Molecular Virology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India.
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Kitagawa Y, Kameoka M, Shoji-Kawata S, Iwabu Y, Mizuta H, Tokunaga K, Fujino M, Natori Y, Yura Y, Ikuta K. Inhibitory function of adapter-related protein complex 2 alpha 1 subunit in the process of nuclear translocation of human immunodeficiency virus type 1 genome. Virology 2008; 373:171-80. [PMID: 18178234 DOI: 10.1016/j.virol.2007.11.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 10/01/2007] [Accepted: 11/30/2007] [Indexed: 11/29/2022]
Abstract
The transfection of human cells with siRNA against adapter-related protein complex 2 alpha 1 subunit (AP2alpha) was revealed to significantly up-regulate the replication of human immunodeficiency virus type 1 (HIV-1). This effect was confirmed by cell infection with vesicular stomatitis virus G protein-pseudotyped HIV-1 as well as CXCR4-tropic and CCR5-tropic HIV-1. Viral adsorption, viral entry and reverse transcription processes were not affected by cell transfection with siRNA against AP2alpha. In contrast, viral nuclear translocation as well as the integration process was significantly up-regulated in cells transfected with siRNA against AP2alpha. Confocal fluorescence microscopy revealed that a subpopulation of AP2alpha was not only localized in the cytoplasm but was also partly co-localized with lamin B, importin beta and Nup153, implying that AP2alpha negatively regulates HIV-1 replication in the process of nuclear translocation of viral DNA in the cytoplasm or the perinuclear region. We propose that AP2alpha may be a novel target for disrupting HIV-1 replication in the early stage of the viral life cycle.
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Affiliation(s)
- Yukiko Kitagawa
- Department of Virology, Research Institute for Microbial Diseases and Osaka University, Osaka 565-0871, Japan
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