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Waheed AA, Zhu Y, Agostino E, Naing L, Hikichi Y, Soheilian F, Yoo SW, Song Y, Zhang P, Slusher BS, Haughey NJ, Freed EO. Neutral sphingomyelinase 2 is required for HIV-1 maturation. Proc Natl Acad Sci U S A 2023; 120:e2219475120. [PMID: 37406093 PMCID: PMC10334776 DOI: 10.1073/pnas.2219475120] [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: 11/18/2022] [Accepted: 04/11/2023] [Indexed: 07/07/2023] Open
Abstract
HIV-1 assembly occurs at the inner leaflet of the plasma membrane (PM) in highly ordered membrane microdomains. The size and stability of membrane microdomains is regulated by activity of the sphingomyelin hydrolase neutral sphingomyelinase 2 (nSMase2) that is localized primarily to the inner leaflet of the PM. In this study, we demonstrate that pharmacological inhibition or depletion of nSMase2 in HIV-1-producer cells results in a block in the processing of the major viral structural polyprotein Gag and the production of morphologically aberrant, immature HIV-1 particles with severely impaired infectivity. We find that disruption of nSMase2 also severely inhibits the maturation and infectivity of other primate lentiviruses HIV-2 and simian immunodeficiency virus, has a modest or no effect on nonprimate lentiviruses equine infectious anemia virus and feline immunodeficiency virus, and has no effect on the gammaretrovirus murine leukemia virus. These studies demonstrate a key role for nSMase2 in HIV-1 particle morphogenesis and maturation.
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Affiliation(s)
- Abdul A. Waheed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD21702
| | - Yanan Zhu
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, OxfordOX3 7BN, United Kingdom
| | - Eva Agostino
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD21702
| | - Lwar Naing
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD21702
| | - Yuta Hikichi
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD21702
| | - Ferri Soheilian
- Electron Microscopy Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Frederick, MD21702
| | - Seung-Wan Yoo
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - Yun Song
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, DidcotOX11 0DE, United Kingdom
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, OxfordOX3 7BN, United Kingdom
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, DidcotOX11 0DE, United Kingdom
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, OxfordOX3 7BN, United Kingdom
| | - Barbara S. Slusher
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD21287
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, MD21287
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - Norman J. Haughey
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD21287
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD21702
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2
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Alfadhli A, Romanaggi C, Barklis RL, Barklis E. Analysis of HIV-1 envelope cytoplasmic tail effects on viral replication. Virology 2023; 579:54-66. [PMID: 36603533 PMCID: PMC10003682 DOI: 10.1016/j.virol.2022.12.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/27/2022] [Accepted: 12/28/2022] [Indexed: 01/03/2023]
Abstract
Trimers of the HIV-1 envelope (Env) protein perform receptor binding and virus-cell fusion functions during the virus life cycle. The cytoplasmic tail (CT) of Env forms an unusual baseplate structure, and is palmitoylated, rich in arginines, carries trafficking motifs, binds cholesterol, and interacts with host proteins. To dissect CT activities, we examined a panel of Env variants, including CT truncations, mutations, and an extension. We found that whereas all variants could replicate in permissive cells, viruses with CT truncations or baseplate mutations were defective in restrictive cells. We also identified a determinant in HIV-1 amphotericin sensitivity, and characterized variants that escape amphotericin inhibition via viral protease-mediated CT cleavage. Results additionally showed that full-length, his tagged Env can oligomerize and be co-assembled with CT truncations that delete portions of the baseplate, host protein binding sites, and trafficking signals. Our observations illuminate novel aspects of HIV-1 CT structure, interactions, and functions.
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Affiliation(s)
- Ayna Alfadhli
- Department of Molecular Microbiology and Immunology, Oregon Health and Sciences University, Portland, OR, USA
| | - CeAnn Romanaggi
- Department of Molecular Microbiology and Immunology, Oregon Health and Sciences University, Portland, OR, USA
| | - Robin Lid Barklis
- Department of Molecular Microbiology and Immunology, Oregon Health and Sciences University, Portland, OR, USA
| | - Eric Barklis
- Department of Molecular Microbiology and Immunology, Oregon Health and Sciences University, Portland, OR, USA.
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3
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Baghirova AA, Kasumov KM. Antifungal Macrocycle Antibiotic Amphotericin B-Its Present and Future. Multidisciplinary Perspective for the Use in the Medical Practice. BIOCHEMISTRY (MOSCOW) SUPPLEMENT. SERIES B, BIOMEDICAL CHEMISTRY 2022; 16:1-12. [PMID: 35194486 PMCID: PMC8853366 DOI: 10.1134/s1990750822010024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 06/15/2021] [Accepted: 06/22/2021] [Indexed: 12/13/2022]
Abstract
This review is devoted to a broad analysis of the results of studies of the effect of macrocyclic antifungal polyene antibiotic amphotericin B on cell membranes. A detailed study of polyenes has shown that some of them can have not only antifungal, but also antiviral and antitumor effects. Under conditions of global pandemic fungal pathology develops especially quickly and in this case leads to invasive aspergillosis, which contributes to the complication of coronavirus infection in the lungs and even secondary infection with invasive aspergillosis. The treatment of an invasive form of bronchopulmonary aspergillosis is directly related to the immunomodulatory and immunostimulating properties of the macrocyclic polyene drug amphotericin B. The article presents experimental data on the study of the biological activity and membrane properties of amphotericin B and the effect of its chemically modified derivatives, as well as liposomal forms of amphotericin B on viral, bacterial and fungal infections. The mechanism of action of amphotericin B and its analogues is based on their interaction with cellular and lipid membranes, followed by formation of ion channels of molecular size in the membranes. The importance of these studies is that polyenes are sensitive to membranes that contain sterols of a certain structure. The analysis showed that pathogenic fungal cells containing ergosterol were 10−100 times more sensitive to polyene antibiotics than host cell membranes containing cholesterol. The high sterol selectivity of the action of polyenes opens broad prospects for the use of polyene antifungal drugs in practical medicine and pharmacology in the treatment of invasive mycoses and the prevention of atherosclerosis. In this context, it should be noted that polyene antibiotics are the main tool in the study of the biochemical mechanism of changes in the permeability of cell membranes for energy-dependent substrates. Chemical and genetic engineering transformation of the structure of polyene antibiotic molecules opens prospects for the identification and creation of new biologically active forms of the antibiotic that have a high selectivity of action in the treatment of pathogenic infections.
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Affiliation(s)
- A A Baghirova
- Institute of Botany, Azerbaijan National Academy of Sciences, Patamdartskoe shosse 40, AZ1004 Baku, Azerbaijan
| | - Kh M Kasumov
- Institute of Botany, Azerbaijan National Academy of Sciences, Patamdartskoe shosse 40, AZ1004 Baku, Azerbaijan
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4
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Baghirova AA, Kasumov KM. [Antifungal macrocycle antibiotic amphotericin B - its present and future. Multidisciplinary perspective for the use in the medical practice]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2021; 67:311-322. [PMID: 34414889 DOI: 10.18097/pbmc20216704311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This review is devoted to a broad analysis of the results of studies of the effect of macrocyclic antifungal polyene antibiotic amphotericin B on cell membranes. A multi-prolonged study of polyenes showed that some of them can have not only antifungal, but also antiviral and antitumor action. Fungal pathology develops especially quickly and in this case leads to invasive aspergillosis, which contributes to the complication of coronavirus infection in the lungs and even secondary infection with invasive aspergillosis in the context of a global pandemic. The treatment of an invasive form of bronchopulmonary aspergillosis is directly related to the immunomodulatory and immunostimulating properties of the macrocyclic polyene drug amphotericin B. The article presents experimental data on the study of the biological activity and membrane properties of amphotericin B and the effect of its chemically modified derivatives, as well as liposomal forms of amphotericin B on viral, bacterial and fungal infections. The mechanism of action of amphotericin B and its analogues is based on their interaction with cellular and lipid membranes, by forming ion channels of molecular size in them. The importance of these studies is that polyenes are sensitive to membranes that contain sterols of a certain structure. The analysis showed that pathogenic fungal cells containing ergosterol were 10-100 times more sensitive to polyene antibiotics than host cell membranes containing cholesterol. The high sterol selectivity of the action of polyenes opens up broad prospects for the use of polyene antifungal drugs in practical medicine and pharmacology in the treatment of invasive mycoses and the prevention of atherosclerosis. In this connection, it should be noted that polyene antibiotics are the main tool in the study of the biochemical mechanism of changes in the permeability of cell membranes for energy-dependent substrates. Chemical and genetic engineering transformation of the structure of polyene antibiotic molecules opens up prospects for the identification and creation of new biologically active forms of the antibiotic that have a high selectivity of action in the treatment of pathogenic infections.
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Affiliation(s)
- A A Baghirova
- Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
| | - Kh M Kasumov
- Institute of Botany, Azerbaijan National Academy of Sciences, Baku, Azerbaijan
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5
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Anand J, Ghildiyal T, Madhwal A, Bhatt R, Verma D, Rai N. Computational guided approach for drug repurposing against SARS-CoV-2. Future Virol 2021. [PMCID: PMC7923689 DOI: 10.2217/fvl-2020-0403] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Background: In the current SARS-CoV-2 outbreak, drug repositioning emerges as a promising approach to develop efficient therapeutics in comparison to de novo drug development. The present investigation screened 130 US FDA-approved drugs including hypertension, cardiovascular diseases, respiratory tract infections (RTI), antibiotics and antiviral drugs for their inhibitory potential against SARS-CoV-2. Materials & methods: The molecular drug targets against SARS-CoV-2 proteins were determined by the iGEMDOCK computational docking tool. The protein homology models were generated through SWISS Model workspace. The pharmacokinetics of all the ligands was determined by ADMET analysis. Results: The study identified 15 potent drugs exhibiting significant inhibitory potential against SARS-CoV-2. Conclusion: Our investigation has identified possible repurposed drug candidates to improve the current modus operandi of the treatment given to COVID-19 patients.
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Affiliation(s)
- Jigisha Anand
- Department of Biotechnology, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
| | - Tanmay Ghildiyal
- Department of Life Sciences, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
| | - Aakanksha Madhwal
- Department of Life Sciences, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
| | - Rishabh Bhatt
- Department of Life Sciences, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
| | - Devvret Verma
- Department of Biotechnology, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
| | - Nishant Rai
- Department of Biotechnology, Graphic Era (Deemed to be University), Clement Town, Dehradun, Uttarakhand-248001, India
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Nieto‐Garai JA, Arboleya A, Otaegi S, Chojnacki J, Casas J, Fabriàs G, Contreras F, Kräusslich H, Lorizate M. Cholesterol in the Viral Membrane is a Molecular Switch Governing HIV-1 Env Clustering. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2003468. [PMID: 33552873 PMCID: PMC7856888 DOI: 10.1002/advs.202003468] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/13/2020] [Indexed: 05/07/2023]
Abstract
HIV-1 entry requires the redistribution of envelope glycoproteins (Env) into a cluster and the presence of cholesterol (chol) in the viral membrane. However, the molecular mechanisms underlying the specific role of chol in infectivity and the driving force behind Env clustering remain unknown. Here, gp41 is demonstrated to directly interact with chol in the viral membrane via residues 751-854 in the cytoplasmic tail (CT751-854). Super-resolution stimulated emission depletion (STED) nanoscopy analysis of Env distribution further demonstrates that both truncation of gp41 CT751-854 and depletion of chol leads to dispersion of Env clusters in the viral membrane and inhibition of virus entry. This work reveals a direct interaction of gp41 CT with chol and indicates that this interaction is an important orchestrator of Env clustering.
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Affiliation(s)
- Jon Ander Nieto‐Garai
- Instituto Biofisika (UPV/EHU, CSIC)University of the Basque CountryLeioaE‐48940Spain
- Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB)Barrio Sarriena s/nLeioaE‐48940Spain
| | - Aroa Arboleya
- Instituto Biofisika (UPV/EHU, CSIC)University of the Basque CountryLeioaE‐48940Spain
- Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB)Barrio Sarriena s/nLeioaE‐48940Spain
| | - Sara Otaegi
- Instituto Biofisika (UPV/EHU, CSIC)University of the Basque CountryLeioaE‐48940Spain
- Department of Biochemistry and Molecular BiologyFaculty of Science and TechnologyUniversity of the Basque CountryLeioaE‐48940Spain
| | | | - Josefina Casas
- Research Unit on BioActive Molecules. Department of Biological ChemistryInstitute for Advanced Chemistry of Catalonia (IQAC‐CSIC)BarcelonaCatalonia08034Spain
- Liver and Digestive Diseases Networking Biomedical Research Center (CIBEREHD) ISCIIMadrid28029Spain
| | - Gemma Fabriàs
- Research Unit on BioActive Molecules. Department of Biological ChemistryInstitute for Advanced Chemistry of Catalonia (IQAC‐CSIC)BarcelonaCatalonia08034Spain
- Liver and Digestive Diseases Networking Biomedical Research Center (CIBEREHD) ISCIIMadrid28029Spain
| | - F‐Xabier Contreras
- Instituto Biofisika (UPV/EHU, CSIC)University of the Basque CountryLeioaE‐48940Spain
- Department of Biochemistry and Molecular BiologyFaculty of Science and TechnologyUniversity of the Basque CountryLeioaE‐48940Spain
- IkerbasqueBasque Foundation for ScienceBilbao48013Spain
| | - Hans‐Georg Kräusslich
- Department of Infectious DiseasesVirologyUniversitätsklinikum HeidelbergHeidelberg69120Germany
| | - Maier Lorizate
- Instituto Biofisika (UPV/EHU, CSIC)University of the Basque CountryLeioaE‐48940Spain
- Department of Biochemistry and Molecular BiologyFaculty of Science and TechnologyUniversity of the Basque CountryLeioaE‐48940Spain
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LY6E Restricts Entry of Human Coronaviruses, Including Currently Pandemic SARS-CoV-2. J Virol 2020; 94:JVI.00562-20. [PMID: 32641482 PMCID: PMC7459569 DOI: 10.1128/jvi.00562-20] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/05/2020] [Indexed: 12/26/2022] Open
Abstract
Virus entry into host cells is one of the key determinants of host range and cell tropism and is subjected to the control of host innate and adaptive immune responses. In the last decade, several interferon-inducible cellular proteins, including IFITMs, GILT, ADAP2, 25CH, and LY6E, had been identified to modulate the infectious entry of a variety of viruses. Particularly, LY6E was recently identified as a host factor that facilitates the entry of several human-pathogenic viruses, including human immunodeficiency virus, influenza A virus, and yellow fever virus. Identification of LY6E as a potent restriction factor of coronaviruses expands the biological function of LY6E and sheds new light on the immunopathogenesis of human coronavirus infection. C3A is a subclone of the human hepatoblastoma HepG2 cell line with strong contact inhibition of growth. We fortuitously found that C3A was more susceptible to human coronavirus HCoV-OC43 infection than HepG2, which was attributed to the increased efficiency of virus entry into C3A cells. In an effort to search for the host cellular protein(s) mediating the differential susceptibility of the two cell lines to HCoV-OC43 infection, we found that ArfGAP with dual pleckstrin homology (PH) domains 2 (ADAP2), gamma-interferon-inducible lysosome/endosome-localized thiolreductase (GILT), and lymphocyte antigen 6 family member E (LY6E), the three cellular proteins identified to function in interference with virus entry, were expressed at significantly higher levels in HepG2 cells. Functional analyses revealed that ectopic expression of LY6E, but not GILT or ADAP2, in HEK 293 cells inhibited the entry of HCoV-O43. While overexpression of LY6E in C3A and A549 cells efficiently inhibited the infection of HCoV-OC43, knockdown of LY6E expression in HepG2 significantly increased its susceptibility to HCoV-OC43 infection. Moreover, we found that LY6E also efficiently restricted the entry mediated by the envelope spike proteins of other human coronaviruses, including the currently pandemic SARS-CoV-2. Interestingly, overexpression of serine protease TMPRSS2 or amphotericin treatment significantly neutralized the IFN-inducible transmembrane 3 (IFITM3) restriction of human coronavirus (CoV) entry, but did not compromise the effect of LY6E on the entry of human coronaviruses. The work reported herein thus demonstrates that LY6E is a critical antiviral immune effector that controls CoV infection and pathogenesis via a mechanism distinct from other factors that modulate CoV entry. IMPORTANCE Virus entry into host cells is one of the key determinants of host range and cell tropism and is subjected to the control of host innate and adaptive immune responses. In the last decade, several interferon-inducible cellular proteins, including IFITMs, GILT, ADAP2, 25CH, and LY6E, had been identified to modulate the infectious entry of a variety of viruses. Particularly, LY6E was recently identified as a host factor that facilitates the entry of several human-pathogenic viruses, including human immunodeficiency virus, influenza A virus, and yellow fever virus. Identification of LY6E as a potent restriction factor of coronaviruses expands the biological function of LY6E and sheds new light on the immunopathogenesis of human coronavirus infection.
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AL-Khikani FHO. Amphotericin B from antifungal to antiviral therapy: promising modern therapeutic branch. RESEARCH RESULTS IN PHARMACOLOGY 2020. [DOI: 10.3897/rrpharmacology.6.53649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Introduction: Amphotericin B (AmB) which belongs to the polyene group has a wide spectrum in vitro and in vivo antimicrobial activity against fungi and parasites, but resistance to AmB is rare despite extensive use.
Material and methods: Atotal of 2530 articles were investigated in PubMed (n = 1525), Medline (n = 705), and Google Scholar (n = 300). From 2530 articles, only 61 studies were included in this review. All the short and full articles were searched that were scheduled to be published until April 2020.
Results: After its discovery, AmB has been one of the most common first-line choices in treating systemic fungal infection for over seven decades from its discovery. Recently, some studies have focused on the potential antimicrobial action of AmB against some enveloped and non-enveloped viruses, such as human immunodeficiency virus, Japanese encephalitis virus, herpes simplex virus, and Rubella virus.
Discussion: Among the invading pathogens, viruses constitute the most common ones,Due to the continuous spreading of viral infections with the rise in death numbers, new therapeutics development is urgent, as in general, some lethal viruses have no specific antiviral drugs or vaccines. So, this review may serve as an impetus for researchers working in the field of medical microbiology, vaccination, and antiviral drug design by discussing the most recent information about the antiviral action of AmB, as well as trying to provide a deeper understanding of major properties, mechanisms of action, immune system responses, and antimicrobial efficiency of AmB.
Conclusion: Since AmB is expected to alter the structure of the viral envelope, membrane integrity of cells, and internal cellular organelles, besides its other unique properties, such as host immunomodulatory effects, this review suggested that AmB as an effective anti-fungi drug may hold the promise of formulating a novel therapeutic option to treat many dangerous viruses, including those for treating which there are no active drugs or vaccines.
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Sanna G, Madeddu S, Murgia G, Serreli G, Begala M, Caboni P, Incani A, Franci G, Galdiero M, Giliberti G. Potent and Selective Activity against Human Immunodeficiency Virus 1 (HIV-1) of Thymelaea hirsuta Extracts. Viruses 2020; 12:v12060664. [PMID: 32575585 PMCID: PMC7354558 DOI: 10.3390/v12060664] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 12/27/2022] Open
Abstract
Historically, natural products have been the most successful source of inspiration for the development of new drugs. Members of the Thymelaeaceae family have been of interest owing to their excellent medicinal value. Given the successful history of natural product-based drug discovery, extracts from the aerial parts of Thymelaea hirsuta were evaluated for their potential anti-human immunodeficiency virus type 1 (HIV-1) activity. Ethyl acetate extracts from leaves (71B) and branches (72B) of Thymelaea hirsuta showed potent and selective activity against HIV-1 wt (EC50 = 0.8 µg/mL) at non-cytotoxic concentrations (CC50 > 100 µg/mL). They proved to be active against HIV-1 variants carrying clinically relevant NNRTI and NRTI mutations at low concentration (0.3–4 µg/mL range) and against the M-tropic strain HIV-1 BaL. The 72B extract, chosen as a lead, was not able to inhibit the RT and protease enzymatic functions. Furthermore, it was not virucidal, since exposure of HIV to high concentration did not affect virus infectivity. The pre-clinical safety profile of this extract showed no adverse effect on the growth of Lactobacilli, and non-toxic concentration of the extract did not influence the Caco-2 epithelial cells monolayer integrity. Additionally, extract 72B prevented syncytia formation at low concentration (0.4 µg/mL). The potent inhibitory effect on the syncytia formation in co-cultures showed that 72B inhibits an early event in the replication cycle of HIV. All of these findings prompt us to carry on new studies on Thymelaea hirsuta extracts.
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Affiliation(s)
- Giuseppina Sanna
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (S.M.); (G.S.); (A.I.); (G.G.)
- Correspondence:
| | - Silvia Madeddu
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (S.M.); (G.S.); (A.I.); (G.G.)
| | - Giuseppe Murgia
- Department of Inorganic and Analytical Chemistry, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy;
| | - Gabriele Serreli
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (S.M.); (G.S.); (A.I.); (G.G.)
| | - Michela Begala
- Department of Life and Environmental Sciences-Unit of Drug Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (M.B.); (P.C.)
| | - Pierluigi Caboni
- Department of Life and Environmental Sciences-Unit of Drug Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (M.B.); (P.C.)
| | - Alessandra Incani
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (S.M.); (G.S.); (A.I.); (G.G.)
| | - Gianluigi Franci
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy;
| | - Marilena Galdiero
- Department of Experimental Medicine, University of Study of Campania “Luigi Vanvitelli”, Via Costantinopoli 16, 80138 Napoli, Italy;
| | - Gabriele Giliberti
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato, 09042 Cagliari, Italy; (S.M.); (G.S.); (A.I.); (G.G.)
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In Silico Insights into HIV-1 Vpu-Tetherin Interactions and Its Mutational Counterparts. Med Sci (Basel) 2019; 7:medsci7060074. [PMID: 31234536 PMCID: PMC6631454 DOI: 10.3390/medsci7060074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 06/15/2019] [Accepted: 06/19/2019] [Indexed: 11/16/2022] Open
Abstract
Tetherin, an interferon-induced host protein encoded by the bone marrow stromal antigen 2 (BST2/CD317/HM1.24) gene, is involved in obstructing the release of many retroviruses and other enveloped viruses by cross-linking the budding virus particles to the cell surface. This activity is antagonized in the case of human immunodeficiency virus (HIV)-1 wherein its accessory protein Viral Protein U (Vpu) interacts with tetherin, causing its downregulation from the cell surface. Vpu and tetherin connect through their transmembrane (TM) domains, culminating into events leading to tetherin degradation by recruitment of β-TrCP2. However, mutations in the TM domains of both proteins are reported to act as a resistance mechanism to Vpu countermeasure impacting tetherin's sensitivity towards Vpu but retaining its antiviral activity. Our study illustrates the binding aspects of blood-derived, brain-derived, and consensus HIV-1 Vpu with tetherin through protein-protein docking. The analysis of the bound complexes confirms the blood-derived Vpu-tetherin complex to have the best binding affinity as compared to other two. The mutations in tetherin and Vpu are devised computationally and are subjected to protein-protein interactions. The complexes are tested for their binding affinities, residue connections, hydrophobic forces, and, finally, the effect of mutation on their interactions. The single point mutations in tetherin at positions L23Y, L24T, and P40T, and triple mutations at {L22S, F44Y, L37I} and {L23T, L37T, T45I}, while single point mutations in Vpu at positions A19H and W23Y and triplet of mutations at {V10K, A11L, A19T}, {V14T, I18T, I26S}, and {A11T, V14L, A15T} have revealed no polar contacts with minimal hydrophobic interactions between Vpu and tetherin, resulting in reduced binding affinity. Additionally, we have explored the aggregation potential of tetherin and its association with the brain-derived Vpu protein. This work is a possible step toward an understanding of Vpu-tetherin interactions.
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11
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Effect of Chemically Transformed Macrocyclic Polyene Antibiotics on Tumor Cells. Bull Exp Biol Med 2019; 166:735-738. [PMID: 31020586 DOI: 10.1007/s10517-019-04429-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Indexed: 10/26/2022]
Abstract
Comparative analysis of the effects of chemically transformed polyene antibiotics pimaricin, nystatin, lucensomycin, amphotericin B, and levorin on biological objects in vivo and in vitro revealed the greatest biological activity of original amphotericin B and levorin with its derivatives. The study also examined the effects of alkyl derivatives of amphotericin B and levorin modified in certain parts of the lactone ring on the lipid and biological membranes. It is established that methylated levorin possesses larger biological activity than the original antibiotic. Examination of the effects of alkyl derivatives of levorin and amphotericin B on cell cultures C6 (rat glioma) and HeLa (human cervical carcinoma) in vitro revealed the antitumor action of methylated levorin and original amphotericin B.
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12
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Carravilla P, Nieva JL. HIV antivirals: targeting the functional organization of the lipid envelope. Future Virol 2018. [DOI: 10.2217/fvl-2017-0114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Most of the surface of the lipid bilayer covering the human immunodeficiency virus type 1 (HIV-1) particle is directly accessible from the aqueous medium. Its peculiar chemical composition and physical properties appear to be critical for infection and, therefore, may comprise a target for selective antiviral activity. The HIV-1 membrane is enriched in raft-type lipids and also displays aminophospholipids on its external leaflet. We contend here that a great deal of membrane-active compounds described to block HIV-1 infection can do so by following a common mechanism of action: alteration of the lateral heterogeneity that supports the functional organization of the lipid envelope. The confirmation of this hypothesis could lay new foundations for the rational development of compounds with anti-HIV activity.
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Affiliation(s)
- Pablo Carravilla
- Biofisika Institute (CSIC, UPV/EHU) & Department of Biochemistry & Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - José L Nieva
- Biofisika Institute (CSIC, UPV/EHU) & Department of Biochemistry & Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
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13
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Dumas F, Haanappel E. Lipids in infectious diseases - The case of AIDS and tuberculosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:1636-1647. [PMID: 28535936 DOI: 10.1016/j.bbamem.2017.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 05/11/2017] [Accepted: 05/14/2017] [Indexed: 02/07/2023]
Abstract
Lipids play a central role in many infectious diseases. AIDS (Acquired Immune Deficiency Syndrome) and tuberculosis are two of the deadliest infectious diseases to have struck mankind. The pathogens responsible for these diseases, Human Immunodeficiency Virus-1 and Mycobacterium tuberculosis, rely on lipids and on lipid membrane properties to gain access to their host cells, to persist in them and ultimately to egress from their hosts. In this Review, we discuss the life cycles of these pathogens and the roles played by lipids and membranes. We then give an overview of therapies that target lipid metabolism, modulate host membrane properties or implement lipid-based drug delivery systems. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.
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Affiliation(s)
- Fabrice Dumas
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France.
| | - Evert Haanappel
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, France
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14
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Klug YA, Rotem E, Schwarzer R, Shai Y. Mapping out the intricate relationship of the HIV envelope protein and the membrane environment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1859:550-560. [PMID: 27793589 DOI: 10.1016/j.bbamem.2016.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 10/20/2016] [Accepted: 10/24/2016] [Indexed: 01/08/2023]
Abstract
The HIV gp160 envelope fusion protein is situated in the viral membrane and mediates virus entry into its host cell. Increasing evidence suggests that virtually all parts of the HIV envelope are structurally and functionally dependent on membranes. Protein-lipid interactions and membrane properties influence the dynamics of a manifold of gp160 biological activities such as membrane fusion, immune suppression and gp160 incorporation into virions during HIV budding and assembly. In the following we will summarize our current understanding of this interdependence between membrane interaction, structural conformation and functionality of the different gp160 domains. This article is part of a Special Issue entitled: Lipid order/lipid defects and lipid-control of protein activity edited by Dirk Schneider.
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Affiliation(s)
- Yoel A Klug
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Etai Rotem
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Roland Schwarzer
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Yechiel Shai
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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15
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Xu F, Zhao X, Hu S, Li J, Yin L, Mei S, Liu T, Wang Y, Ren L, Cen S, Zhao Z, Wang J, Jin Q, Liang C, Ai B, Guo F. Amphotericin B Inhibits Enterovirus 71 Replication by Impeding Viral Entry. Sci Rep 2016; 6:33150. [PMID: 27608771 PMCID: PMC5016833 DOI: 10.1038/srep33150] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/22/2016] [Indexed: 12/03/2022] Open
Abstract
Enterovirus 71 (EV71) infection causes hand-foot-and-mouth disease that leads to cardiopulmonary complications and death in young children. There is thus an urgent need to find new treatments to control EV71 infection. In this study, we report potent inhibition of EV71 by a polyene antibiotic Amphotericin B. Amphotericin B profoundly diminished the expression of EV71 RNA and viral proteins in the RD cells and the HEK293 cells. As a result, EV71 production was inhibited by Amphotericin B with an EC50 (50% effective concentration) of 1.75 μM in RD cells and 0.32 μM in 293 cells. In addition to EV71, EV68 was also strongly inhibited by Amphotericin B. Results of mechanistic studies revealed that Amphotericin B targeted the early stage of EV71 infection through impairing the attachment and internalization of EV71 by host cells. As an effective anti-fungi drug, Amphotericin B thus holds the promise of formulating a novel therapeutic to treat EV71 infection.
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Affiliation(s)
- Fengwen Xu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Xiaoxiao Zhao
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Siqi Hu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Jian Li
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Lijuan Yin
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Shan Mei
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Tingting Liu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Ying Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Lili Ren
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Shan Cen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Zhendong Zhao
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Jianwei Wang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Qi Jin
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
| | - Chen Liang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
- Lady Davis Institute, Jewish General Hospital, Montreal, Qc, Canada H3T 1E2
| | - Bin Ai
- Department of Medical Oncology, Beijing Hospital, Beijing, P. R. China
| | - Fei Guo
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, and Center for AIDS Research, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, P. R. China
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16
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Mercredi PY, Bucca N, Loeliger B, Gaines CR, Mehta M, Bhargava P, Tedbury PR, Charlier L, Floquet N, Muriaux D, Favard C, Sanders CR, Freed EO, Marchant J, Summers MF. Structural and Molecular Determinants of Membrane Binding by the HIV-1 Matrix Protein. J Mol Biol 2016; 428:1637-55. [PMID: 26992353 DOI: 10.1016/j.jmb.2016.03.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/09/2016] [Accepted: 03/10/2016] [Indexed: 10/22/2022]
Abstract
Assembly of HIV-1 particles is initiated by the trafficking of viral Gag polyproteins from the cytoplasm to the plasma membrane, where they co-localize and bud to form immature particles. Membrane targeting is mediated by the N-terminally myristoylated matrix (MA) domain of Gag and is dependent on the plasma membrane marker phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2]. Recent studies revealed that PI(4,5)P2 molecules containing truncated acyl chains [tr-PI(4,5)P2] are capable of binding MA in an "extended lipid" conformation and promoting myristoyl exposure. Here we report that tr-PI(4,5)P2 molecules also readily bind to non-membrane proteins, including HIV-1 capsid, which prompted us to re-examine MA-PI(4,5)P2 interactions using native lipids and membrane mimetic liposomes and bicelles. Liposome binding trends observed using a recently developed NMR approach paralleled results of flotation assays, although the affinities measured under the equilibrium conditions of NMR experiments were significantly higher. Native PI(4,5)P2 enhanced MA binding to liposomes designed to mimic non-raft-like regions of the membrane, suggesting the possibility that binding of the protein to disordered domains may precede Gag association with, or nucleation of, rafts. Studies with bicelles revealed a subset of surface and myr-associated MA residues that are sensitive to native PI(4,5)P2, but cleft residues that interact with the 2'-acyl chains of tr-PI(4,5)P2 molecules in aqueous solution were insensitive to native PI(4,5)P2 in bicelles. Our findings call to question extended-lipid MA:membrane binding models, and instead support a model put forward from coarse-grained simulations indicating that binding is mediated predominantly by dynamic, electrostatic interactions between conserved basic residues of MA and multiple PI(4,5)P2 and phosphatidylserine molecules.
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Affiliation(s)
- Peter Y Mercredi
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Nadine Bucca
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Burk Loeliger
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Christy R Gaines
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Mansi Mehta
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Pallavi Bhargava
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Philip R Tedbury
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, National Cancer Institute at Fredrick, Fredrick, MD 21702-1201, USA
| | - Landry Charlier
- Institut des Biomolécules Max Mousseron, CNRS UMR5247, Université Montpellier, Faculté de Pharmacie, Montpellier Cedex 05, France
| | - Nicolas Floquet
- Institut des Biomolécules Max Mousseron, CNRS UMR5247, Université Montpellier, Faculté de Pharmacie, Montpellier Cedex 05, France
| | - Delphine Muriaux
- Centre d'études d'agents Pathogénes et Biotechnologies pour la Santé CNRS-UMR 5236, Université Montpellier, Montpellier Cedex 5, France
| | - Cyril Favard
- Centre d'études d'agents Pathogénes et Biotechnologies pour la Santé CNRS-UMR 5236, Université Montpellier, Montpellier Cedex 5, France
| | - Charles R Sanders
- Department of Biochemistry, Center for Structural Biology, and Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN 37240-7917, USA
| | - Eric O Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, National Cancer Institute at Fredrick, Fredrick, MD 21702-1201, USA.
| | - Jan Marchant
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA.
| | - Michael F Summers
- Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of Maryland, Baltimore County, Baltimore, MD 21250, USA.
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17
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Hawkes D, Jones KL, Smyth RP, Pereira CF, Bittman R, Jaworowski A, Mak J. Properties of HIV-1 associated cholesterol in addition to raft formation are important for virus infection. Virus Res 2015; 210:18-21. [DOI: 10.1016/j.virusres.2015.06.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 06/25/2015] [Accepted: 06/25/2015] [Indexed: 11/28/2022]
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18
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Overexpression of inactive tetherin delGPI mutant inhibits HIV-1 Vpu-mediated antagonism of endogenous tetherin. FEBS Lett 2012. [PMID: 23201263 DOI: 10.1016/j.febslet.2012.11.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tetherin/BST-2/CD317 inhibits HIV-1 release from infected cells, but the viral Vpu protein efficiently antagonizes this antiviral activity through direct interaction between the transmembrane (TM) domains of each protein. Here, we demonstrated that overexpression of an inactive tetherin delGPI mutant, the TM domain of which could competitively block Vpu targeting of endogenous tetherin, potently inhibited HIV-1 release from human tetherin-positive cells in both transient and stable expression conditions. These results also suggest that heterologous dimerization occurred between the delGPI mutant and endogenous tetherin. These findings suggest that blocking the Vpu/tetherin interface may be a novel therapeutic approach against HIV-1 release.
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Abstract
The limited therapeutic arsenal and the increase in reports of fungal resistance to multiple antifungal agents have made fungal infections a major therapeutic challenge. The polyene antibiotics are the only group of antifungal antibiotics that directly target the plasma membrane via a specific interaction with the main fungal sterol, ergosterol, often resulting in membrane permeabilization. In contrast to other polyene antibiotics that form pores in the membrane, the mode of action of natamycin has remained obscure but is not related to membrane permeabilization. Here, we demonstrate that natamycin inhibits growth of yeasts and fungi via the immediate inhibition of amino acid and glucose transport across the plasma membrane. This is attributable to ergosterol-specific and reversible inhibition of membrane transport proteins. It is proposed that ergosterol-dependent inhibition of membrane proteins is a general mode of action of all the polyene antibiotics, of which some have been shown additionally to permeabilize the plasma membrane. Our results imply that sterol-protein interactions are fundamentally important for protein function even for those proteins that are not known to reside in sterol-rich domains.
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20
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Fischer WB, Wang YT, Schindler C, Chen CP. Mechanism of function of viral channel proteins and implications for drug development. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 294:259-321. [PMID: 22364876 PMCID: PMC7149447 DOI: 10.1016/b978-0-12-394305-7.00006-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Viral channel-forming proteins comprise a class of viral proteins which, similar to their host companions, are made to alter electrochemical or substrate gradients across lipid membranes. These proteins are active during all stages of the cellular life cycle of viruses. An increasing number of proteins are identified as channel proteins, but the precise role in the viral life cycle is yet unknown for the majority of them. This review presents an overview about these proteins with an emphasis on those with available structural information. A concept is introduced which aligns the transmembrane domains of viral channel proteins with those of host channels and toxins to give insights into the mechanism of function of the viral proteins from potential sequence identities. A summary of to date investigations on drugs targeting these proteins is given and discussed in respect of their mode of action in vivo.
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Affiliation(s)
- Wolfgang B. Fischer
- Institute of Biophotonics, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei 112, Taiwan
| | - Yi-Ting Wang
- Institute of Biophotonics, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei 112, Taiwan
| | - Christina Schindler
- Institute of Biophotonics, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei 112, Taiwan
| | - Chin-Pei Chen
- Institute of Biophotonics, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei 112, Taiwan
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21
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Dubé M, Paquay C, Roy BB, Bego MG, Mercier J, Cohen EA. HIV-1 Vpu antagonizes BST-2 by interfering mainly with the trafficking of newly synthesized BST-2 to the cell surface. Traffic 2011; 12:1714-29. [PMID: 21902775 DOI: 10.1111/j.1600-0854.2011.01277.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Bone marrow stromal cell antigen-2 (BST-2) inhibits human immunodeficiency virus type 1 (HIV-1) release by cross-linking nascent virions on infected cell surface. HIV-1 Vpu is thought to antagonize BST-2 by downregulating its surface levels via a mechanism that involves intracellular sequestration and lysosomal degradation. Here, we investigated the functional importance of cell-surface BST-2 downregulation and the BST-2 pools targeted by Vpu using an inducible proviral expression system. Vpu established a surface BST-2 equilibrium at ∼60% of its initial levels within 6 h, a condition that coincided with detection of viral release. Analysis of BST-2 post-endocytic trafficking revealed that the protein is engaged in a late endosomal pathway independent of Vpu. While Vpu moderately enhanced cell-surface BST-2 clearance, it strongly affected the protein resupply to the plasma membrane via newly synthesized proteins. Noticeably, Vpu affected clearance of surface BST-2 more substantially in Jurkat T cells than in HeLa cells, suggesting a cell-dependent impact of Vpu on the pool of surface BST-2. Collectively, our data reveal that Vpu imposes a new BST-2 equilibrium, incompatible with efficient restriction of HIV-1 release, by combining an acceleration of surface BST-2 natural clearance, whose degree might be cell-type dependent, to a severe impairment of the protein resupply to the plasma membrane.
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Affiliation(s)
- Mathieu Dubé
- Laboratory of Human Retrovirology, Institut de recherches cliniques de Montréal, 110 avenue des Pins ouest, Montreal, Quebec, Canada
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22
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Checkley MA, Luttge BG, Freed EO. HIV-1 envelope glycoprotein biosynthesis, trafficking, and incorporation. J Mol Biol 2011; 410:582-608. [PMID: 21762802 PMCID: PMC3139147 DOI: 10.1016/j.jmb.2011.04.042] [Citation(s) in RCA: 328] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 04/14/2011] [Accepted: 04/15/2011] [Indexed: 12/13/2022]
Abstract
The HIV-1 envelope (Env) glycoproteins play an essential role in the virus replication cycle by mediating the fusion between viral and cellular membranes during the entry process. The Env glycoproteins are synthesized as a polyprotein precursor (gp160) that is cleaved by cellular proteases to the mature surface glycoprotein gp120 and the transmembrane glycoprotein gp41. During virus assembly, the gp120/gp41 complex is incorporated as heterotrimeric spikes into the lipid bilayer of nascent virions. These gp120/gp41 complexes then initiate the infection process by binding receptor and coreceptor on the surface of target cells. Much is currently known about the HIV-1 Env glycoprotein trafficking pathway and the structure of gp120 and the extracellular domain of gp41. However, the mechanism by which the Env glycoprotein complex is incorporated into virus particles remains incompletely understood. Genetic data support a major role for the cytoplasmic tail of gp41 and the matrix domain of Gag in Env glycoprotein incorporation. Still to be defined are the identities of host cell factors that may promote Env incorporation and the role of specific membrane microdomains in this process. Here, we review our current understanding of HIV-1 Env glycoprotein trafficking and incorporation into virions.
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Affiliation(s)
- Mary Ann Checkley
- Virus-Cell Interaction Section, HIV Drug Resistance Program National Cancer Institute Frederick, MD 21702
| | - Benjamin G. Luttge
- Virus-Cell Interaction Section, HIV Drug Resistance Program National Cancer Institute Frederick, MD 21702
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Drug Resistance Program National Cancer Institute Frederick, MD 21702
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23
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Lv M, Wang J, Wang X, Zuo T, Zhu Y, Kong W, Yu X. Polarity changes in the transmembrane domain core of HIV-1 Vpu inhibits its anti-tetherin activity. PLoS One 2011; 6:e20890. [PMID: 21674066 PMCID: PMC3107245 DOI: 10.1371/journal.pone.0020890] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 05/12/2011] [Indexed: 11/18/2022] Open
Abstract
Tetherin (BST-2/CD317) is an interferon-inducible antiviral protein that restricts the release of enveloped viruses from infected cells. The HIV-1 accessory protein Vpu can efficiently antagonize this restriction. In this study, we analyzed mutations of the transmembrane (TM) domain of Vpu, including deletions and substitutions, to delineate amino acids important for HIV-1 viral particle release and in interactions with tetherin. The mutants had similar subcellular localization patterns with that of wild-type Vpu and were functional with respect to CD4 downregulation. We showed that the hydrophobic binding surface for tetherin lies in the core of the Vpu TM domain. Three consecutive hydrophobic isoleucine residues in the middle region of the Vpu TM domain, I15, I16 and I17, were important for stabilizing the tetherin binding interface and determining its sensitivity to tetherin. Changing the polarity of the amino acids at these positions resulted in severe impairment of Vpu-induced tetherin targeting and antagonism. Taken together, these data reveal a model of specific hydrophobic interactions between Vpu and tetherin, which can be potentially targeted in the development of novel anti-HIV-1 drugs.
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Affiliation(s)
- Mingyu Lv
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
| | - Jiawen Wang
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
| | - Xiaodan Wang
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
| | - Tao Zuo
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
| | - Yingzi Zhu
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
| | - Wei Kong
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
- * E-mail: (WK); (XY)
| | - Xianghui Yu
- National Engineering Laboratory For AIDS Vaccine, College of Life Science, Jilin University, Changchun, Jilin Province, People's Republic of China
- * E-mail: (WK); (XY)
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24
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Kuhl BD, Sloan RD, Donahue DA, Bar-Magen T, Liang C, Wainberg MA. Tetherin restricts direct cell-to-cell infection of HIV-1. Retrovirology 2010; 7:115. [PMID: 21184674 PMCID: PMC3017029 DOI: 10.1186/1742-4690-7-115] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 12/24/2010] [Indexed: 01/10/2023] Open
Abstract
Background Tetherin (BST-2/CD317/HM1.24) is an interferon (IFN)-inducible factor of the innate immune system, recently shown to exert antiviral activity against HIV-1 and other enveloped viruses by tethering nascent viral particles to the cell surface, thereby inhibiting viral release. In HIV-1 infection, the viral protein U (Vpu) counteracts this antiviral action by down-modulating tetherin from the cell surface. Viral dissemination between T-cells can occur via cell-free transmission or the more efficient direct cell-to-cell route through lipid raft-rich virological synapses, to which tetherin localizes. Results We established a flow cytometry-based co-culture assay to distinguish viral transfer from viral transmission and investigated the influence of tetherin on cell-to-cell spread of HIV-1. Sup-T1 cells inducible for tetherin expression were used to examine the impact of effector and target cell tetherin expression on virus transfer and transmission. Using this assay, we showed that tetherin inhibits direct cell-to-cell virus transfer and transmission. Viral Vpu promoted viral transmission from tetherin-expressing cells by down-modulating tetherin from the effector cell surface. Further, we showed that tetherin on the target cell promotes viral transfer and transmission. Viral infectivity in itself was not affected by tetherin. Conclusion In addition to inhibiting viral release, tetherin also inhibits direct cell-to-cell spread. Viral protein Vpu counteracts this restriction, outweighing its possible cost of fitness in cell-to-cell transmission. The differential role of tetherin in effector and target cells suggest a role for tetherin in cell-cell contacts and virological synapses.
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Affiliation(s)
- Björn D Kuhl
- McGill University AIDS Center, Lady Davis Institute, Jewish General Hospital, Montréal, Canada
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25
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Neumann A, Baginski M, Czub J. How Do Sterols Determine the Antifungal Activity of Amphotericin B? Free Energy of Binding between the Drug and Its Membrane Targets. J Am Chem Soc 2010; 132:18266-72. [DOI: 10.1021/ja1074344] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anna Neumann
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdansk University of Technology, Narutowicza St. 11/12, 80-233 Gdansk, Poland
| | - Maciej Baginski
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdansk University of Technology, Narutowicza St. 11/12, 80-233 Gdansk, Poland
| | - Jacek Czub
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdansk University of Technology, Narutowicza St. 11/12, 80-233 Gdansk, Poland
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Ohmine S, Sakuma R, Sakuma T, Thatava T, Solis GP, Ikeda Y. Cytoplasmic body component TRIM5{alpha} requires lipid-enriched microdomains for efficient HIV-1 restriction. J Biol Chem 2010; 285:34508-17. [PMID: 20810659 DOI: 10.1074/jbc.m110.158188] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
TRIM5α is a member of the tripartite motif (TRIM) family of proteins and affects both early and late phases of the retroviral life cycle. Although TRIM5α multimerizes to form cytoplasmic bodies, which are thought to play an important role in viral restriction, the identity of TRIM5α-containing cytoplasmic bodies remains elusive. To better understand TRIM5α cytoplasmic body constituents and the cellular proteins that could be involved in the TRIM5α-mediated antiviral activities, we sought TRIM5α-binding factors. We identified a lipid microdomain protein flotillin-1/Reggie-2 as an interacting partner of TRIM5α via co-immunoprecipitation. Immunohistochemistry studies confirmed the co-localization of rhesus monkey TRIM5α (TRIM5αrh) cytoplasmic bodies with flotillin-1/Reggie-2. Caveolin-1, another lipid microdomain-associated protein, also co-localized with TRIM5α cytoplasmic bodies. Intriguingly, disruption of cellular cholesterol by cyclodextrin perturbed TRIM5α cytoplasmic body formation. Furthermore, lipid starvation partially relieved the endogenous post-entry restriction of HIV-1 infection, which could be subsequently restored by lipid repletion. These observations indicate the involvement of cellular lipids in TRIM5α-mediated antiviral activities. Given that many viruses utilize cellular lipid microdomains for viral entry and assembly, it is plausible that lipid-enriched domains provide microenvironments where TRIM5α recognizes retroviral components.
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Affiliation(s)
- Seiga Ohmine
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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Ejara ED, Lynen L, Boelaert M, Van Griensven J. Challenges in HIV and visceral Leishmania co-infection: future research directions. Trop Med Int Health 2010; 15:1266-7. [PMID: 20723183 DOI: 10.1111/j.1365-3156.2010.02612.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Retroviruses undergo several critical steps to complete a replication cycle. These include the complex processes of virus entry, assembly, and budding that often take place at the plasma membrane of the host cell. Both virus entry and release involve membrane fusion/fission reactions between the viral envelopes and host cell membranes. Accumulating evidence indicates important roles for lipids and lipid microdomains in virus entry and egress. In this review, we outline the current understanding of the role of lipids and membrane microdomains in retroviral replication.
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Abstract
Advances in cell biology and biophysics revealed that cellular membranes consist of multiple microdomains with specific sets of components such as lipid rafts and TEMs (tetraspanin-enriched microdomains). An increasing number of enveloped viruses have been shown to utilize these microdomains during their assembly. Among them, association of HIV-1 (HIV type 1) and other retroviruses with lipid rafts and TEMs within the PM (plasma membrane) is well documented. In this review, I describe our current knowledge on interrelationships between PM microdomain organization and the HIV-1 particle assembly process. Microdomain association during virus particle assembly may also modulate subsequent virus spread. Potential roles played by microdomains will be discussed with regard to two post-assembly events, i.e., inhibition of virus release by a raft-associated protein BST-2/tetherin and cell-to-cell HIV-1 transmission at virological synapses.
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Arhel N, Kirchhoff F. Host proteins involved in HIV infection: New therapeutic targets. Biochim Biophys Acta Mol Basis Dis 2010; 1802:313-21. [PMID: 20018238 DOI: 10.1016/j.bbadis.2009.12.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 12/08/2009] [Accepted: 12/08/2009] [Indexed: 12/18/2022]
Affiliation(s)
- Nathalie Arhel
- Institute of Molecular Virology, Universitätsklinikum Ulm, Albert-Einstein-Allee 11, 81089 Ulm, Germany.
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31
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Adamson CS, Freed EO. Novel approaches to inhibiting HIV-1 replication. Antiviral Res 2010; 85:119-41. [PMID: 19782103 PMCID: PMC2815006 DOI: 10.1016/j.antiviral.2009.09.009] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 09/09/2009] [Accepted: 09/12/2009] [Indexed: 01/17/2023]
Abstract
Considerable success has been achieved in the treatment of HIV-1 infection, and more than two-dozen antiretroviral drugs are available targeting several distinct steps in the viral replication cycle. However, resistance to these compounds emerges readily, even in the context of combination therapy. Drug toxicity, adverse drug-drug interactions, and accompanying poor patient adherence can also lead to treatment failure. These considerations make continued development of novel antiretroviral therapeutics necessary. In this article, we highlight a number of steps in the HIV-1 replication cycle that represent promising targets for drug discovery. These include lipid raft microdomains, the RNase H activity of the viral enzyme reverse transcriptase, uncoating of the viral core, host cell machinery involved in the integration of the viral DNA into host cell chromatin, virus assembly, maturation, and budding, and the functions of several viral accessory proteins. We discuss the relevant molecular and cell biology, and describe progress to date in developing inhibitors against these novel targets. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of antiretroviral drug discovery and development, Vol 85, issue 1, 2010.
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Affiliation(s)
- Catherine S. Adamson
- Virus-Cell Interaction Section, HIV Drug Resistance Program, National Cancer Institute at Frederick, Maryland, 21702-1201
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Drug Resistance Program, National Cancer Institute at Frederick, Maryland, 21702-1201
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Effect of mutations in the human immunodeficiency virus type 1 protease on cleavage of the gp41 cytoplasmic tail. J Virol 2009; 84:3121-6. [PMID: 20042499 DOI: 10.1128/jvi.02002-09] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously reported that human immunodeficiency virus type 1 (HIV-1) develops resistance to the cholesterol-binding compound amphotericin B methyl ester (AME) by acquiring mutations (P203L and S205L) in the cytoplasmic tail of the transmembrane envelope glycoprotein gp41 that create cleavage sites for the viral protease (PR). In the present study, we observed that a PR inhibitor-resistant (PIR) HIV-1 mutant is unable to efficiently cleave the gp41 cytoplasmic tail in P203L and S205L virions, resulting in loss of AME resistance. To define the pathway to AME resistance in the context of the PIR PR, we selected for resistance with an HIV-1 isolate expressing the mutant enzyme. We identified a new gp41 mutation, R236L, that results in cleavage of the gp41 tail by the PIR PR. These results highlight the central role of gp41 cleavage as the primary mechanism of AME resistance.
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Deficiency of niemann-pick type C-1 protein impairs release of human immunodeficiency virus type 1 and results in Gag accumulation in late endosomal/lysosomal compartments. J Virol 2009; 83:7982-95. [PMID: 19474101 DOI: 10.1128/jvi.00259-09] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) relies on cholesterol-laden lipid raft membrane microdomains for entry into and egress out of susceptible cells. In the present study, we examine the need for intracellular cholesterol trafficking pathways with respect to HIV-1 biogenesis using Niemann-Pick type C-1 (NPC1)-deficient (NPCD) cells, wherein these pathways are severely compromised, causing massive accumulation of cholesterol in late endosomal/lysosomal (LE/L) compartments. We have found that induction of an NPC disease-like phenotype through treatment of various cell types with the commonly used hydrophobic amine drug U18666A resulted in profound suppression of HIV-1 release. Further, NPCD Epstein-Barr virus-transformed B lymphocytes and fibroblasts from patients with NPC disease infected with a CD4-independent strain of HIV-1 or transfected with an HIV-1 proviral clone, respectively, replicated HIV-1 poorly compared to normal cells. Infection of the NPCD fibroblasts with a vesicular stomatitis virus G-pseudotyped strain of HIV-1 produced similar results, suggesting a postentry block to HIV-1 replication in these cells. Examination of these cells using confocal microscopy showed an accumulation and stabilization of Gag in LE/L compartments. Additionally, normal HIV-1 production could be restored in NPCD cells upon expression of a functional NPC1 protein, and overexpression of NPC1 increased HIV-1 release. Taken together, our findings demonstrate that intact intracellular cholesterol trafficking pathways mediated by NPC1 are needed for efficient HIV-1 production.
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Waheed AA, Freed EO. Lipids and membrane microdomains in HIV-1 replication. Virus Res 2009; 143:162-76. [PMID: 19383519 DOI: 10.1016/j.virusres.2009.04.007] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Revised: 04/01/2009] [Accepted: 04/03/2009] [Indexed: 10/20/2022]
Abstract
Several critical steps in the replication cycle of human immunodeficiency virus type 1 (HIV-1) - entry, assembly and budding - are complex processes that take place at the plasma membrane of the host cell. A growing body of data indicates that these early and late steps in HIV-1 replication take place in specialized plasma membrane microdomains, and that many of the viral and cellular components required for entry, assembly, and budding are concentrated in these microdomains. In particular, a number of studies have shown that cholesterol- and sphingolipid-enriched microdomains known as lipid rafts play important roles in multiple steps in the virus replication cycle. In this review, we provide an overview of what is currently known about the involvement of lipids and membrane microdomains in HIV-1 replication.
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Affiliation(s)
- Abdul A Waheed
- Virus-Cell Interaction Section, HIV Drug Resistance Program, National Cancer Institute, Frederick, MD 21702, USA.
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Abstract
Virus particle formation of HIV-1 is a multi-step process driven by a viral structural protein Gag. This process takes place at the plasma membrane in most cell types. However, the pathway that directs Gag to the plasma membrane has recently come under intense scrutiny because of its importance in production of progeny virions as well as virus transmission at cell-cell contacts. This review highlights recent advances in our current understanding of mechanisms that traffic and localize Gag to the plasma membrane. In addition, findings on Gag association with specific plasma membrane domains are discussed in light of potential roles in cell-to-cell transmission.
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