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Zhang T, Shang F, Ma Y, Xu Y, Sun W, Song H. Caveolin-1 Promotes the Imbalance of Th17/Treg in Chronic Obstructive Pulmonary Disease by Regulating Hsp70 Expression. Int J Chron Obstruct Pulmon Dis 2023; 18:565-574. [PMID: 37077366 PMCID: PMC10106795 DOI: 10.2147/copd.s398780] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 03/27/2023] [Indexed: 04/21/2023] Open
Abstract
Objective To investigate whether the expression of Hsp70 is associated with Cav-1 in promoting the imbalance of Th17/Treg cells in COPD. Methods The plasma Cav-1, Hsp70 expression were quantified by enzyme-linked immunosorbent assay (ELISA). The frequencies of circulating Th17, Treg cells and Th17/Treg ratio were determined by flow cytometry. Peripheral blood mononuclear cells (PBMCs) from subjects were transfected with Cav-1 or control plasmids and Hsp70 plasmid. Results We found that Cav-1 expression was lower but the levels of Hsp70 and Th17 cells were higher in COPD than in healthy control (HC). Hsp70 expressions were positively correlated with Cav-1 levels, Th17 cells, and Th17/Treg ratio in COPD but not in HC. Cav-1 over-expression resulted in an increase in Hsp70 and Th17 levels. Suppressing Hsp70 expressing by small interfering RNA (siRNA), the decline of Th17 frequency was observed in Cav-1-overexpressed PBMCs. Conclusion Collectively, our results illuminate that Cav-1 contributes to the imbalance of Th17/Treg through potentially regulating Hsp70 expression.
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Affiliation(s)
- Tongsong Zhang
- Department of Oncology, Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, Qingdao, Shandong, 266042, People’s Republic of China
| | - Fangfang Shang
- Department of Pathology, No. 971 Hospital of People’s Liberation Army Navy, Qingdao, 266071, People’s Republic of China
| | - Yanhui Ma
- Department of Clinical Laboratory, Biotherapy Center, Affiliated Qingdao Central Hospital, Qingdao University, Qingdao, 266042, People’s Republic of China
| | - Yanxia Xu
- Department of Oncology, Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, Qingdao, Shandong, 266042, People’s Republic of China
| | - Weihong Sun
- Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, Qingdao, Shandong, 266042, People’s Republic of China
| | - Haiping Song
- Department of Oncology, Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, Qingdao, Shandong, 266042, People’s Republic of China
- Correspondence: Haiping Song; Yanxia Xu, Department of Oncology, Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, 127 Siliu South Road, Qingdao, 266042, People’s Republic of China, Tel +86 532 8496 2202; +86 532 84962203, Fax +86 532-84963506, Email ;
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2
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Liu W, Tang D, Xu XX, Liu YJ, Jiu Y. How Physical Factors Coordinate Virus Infection: A Perspective From Mechanobiology. Front Bioeng Biotechnol 2021; 9:764516. [PMID: 34778236 PMCID: PMC8585752 DOI: 10.3389/fbioe.2021.764516] [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: 08/25/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Pandemics caused by viruses have threatened lives of thousands of people. Understanding the complicated process of viral infection provides significantly directive implication to epidemic prevention and control. Viral infection is a complex and diverse process, and substantial studies have been complemented in exploring the biochemical and molecular interactions between viruses and hosts. However, the physical microenvironment where infections implement is often less considered, and the role of mechanobiology in viral infection remains elusive. Mechanobiology focuses on sensation, transduction, and response to intracellular and extracellular physical factors by tissues, cells, and extracellular matrix. The intracellular cytoskeleton and mechanosensors have been proven to be extensively involved in the virus life cycle. Furthermore, innovative methods based on micro- and nanofabrication techniques are being utilized to control and modulate the physical and chemical cell microenvironment, and to explore how extracellular factors including stiffness, forces, and topography regulate viral infection. Our current review covers how physical factors in the microenvironment coordinate viral infection. Moreover, we will discuss how this knowledge can be harnessed in future research on cross-fields of mechanobiology and virology.
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Affiliation(s)
- Wei Liu
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Department of Systems Biology for Medicine, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Daijiao Tang
- The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xin-Xin Xu
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Department of Systems Biology for Medicine, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Yan-Jun Liu
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Department of Systems Biology for Medicine, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Yaming Jiu
- The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
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3
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Sahay B, Mergia A. The Potential Contribution of Caveolin 1 to HIV Latent Infection. Pathogens 2020; 9:pathogens9110896. [PMID: 33121153 PMCID: PMC7692328 DOI: 10.3390/pathogens9110896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 12/25/2022] Open
Abstract
Combinatorial antiretroviral therapy (cART) suppresses HIV replication to undetectable levels and has been effective in prolonging the lives of HIV infected individuals. However, cART is not capable of eradicating HIV from infected individuals mainly due to HIV’s persistence in small reservoirs of latently infected resting cells. Latent infection occurs when the HIV-1 provirus becomes transcriptionally inactive and several mechanisms that contribute to the silencing of HIV transcription have been described. Despite these advances, latent infection remains a major hurdle to cure HIV infected individuals. Therefore, there is a need for more understanding of novel mechanisms that are associated with latent infection to purge HIV from infected individuals thoroughly. Caveolin 1(Cav-1) is a multifaceted functional protein expressed in many cell types. The expression of Cav-1 in lymphocytes has been controversial. Recent evidence, however, convincingly established the expression of Cav-1 in lymphocytes. In lieu of this finding, the current review examines the potential role of Cav-1 in HIV latent infection and provides a perspective that helps uncover new insights to understand HIV latent infection.
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Affiliation(s)
| | - Ayalew Mergia
- Correspondence: ; Tel.: +352-294-4139; Fax: +352-392-9704
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4
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Multifaceted Functions of Host Cell Caveolae/Caveolin-1 in Virus Infections. Viruses 2020; 12:v12050487. [PMID: 32357558 PMCID: PMC7291293 DOI: 10.3390/v12050487] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 02/07/2023] Open
Abstract
Virus infection has drawn extensive attention since it causes serious or even deadly diseases, consequently inducing a series of social and public health problems. Caveolin-1 is the most important structural protein of caveolae, a membrane invagination widely known for its role in endocytosis and subsequent cytoplasmic transportation. Caveolae/caveolin-1 is tightly associated with a wide range of biological processes, including cholesterol homeostasis, cell mechano-sensing, tumorigenesis, and signal transduction. Intriguingly, the versatile roles of caveolae/caveolin-1 in virus infections have increasingly been appreciated. Over the past few decades, more and more viruses have been identified to invade host cells via caveolae-mediated endocytosis, although other known pathways have been explored. The subsequent post-entry events, including trafficking, replication, assembly, and egress of a large number of viruses, are caveolae/caveolin-1-dependent. Deprivation of caveolae/caveolin-1 by drug application or gene editing leads to abnormalities in viral uptake, viral protein expression, or virion release, whereas the underlying mechanisms remain elusive and must be explored holistically to provide potential novel antiviral targets and strategies. This review recapitulates our current knowledge on how caveolae/caveolin-1 functions in every step of the viral infection cycle and various relevant signaling pathways, hoping to provide a new perspective for future viral cell biology research.
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Smith JN, Edgar JM, Balk JM, Iftikhar M, Fong JC, Olsen TJ, Fishman DA, Majumdar S, Weiss GA. Directed evolution and biophysical characterization of a full-length, soluble, human caveolin-1 variant. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:963-972. [PMID: 29857161 DOI: 10.1016/j.bbapap.2018.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 05/16/2018] [Accepted: 05/24/2018] [Indexed: 12/22/2022]
Abstract
Protein engineering by directed evolution can alter proteins' structures, properties, and functions. However, membrane proteins, despite their importance to living organisms, remain relatively unexplored as targets for protein engineering and directed evolution. This gap in capabilities likely results from the tendency of membrane proteins to aggregate and fail to overexpress in bacteria cells. For example, the membrane protein caveolin-1 has been implicated in many cell signaling pathways and diseases, yet the full-length protein is too aggregation-prone for detailed mutagenesis, directed evolution, and biophysical characterization. Using a phage-displayed library of full-length caveolin-1 variants, directed evolution with alternating subtractive and functional selections isolated a full-length, soluble variant, termed cavsol, for expression in E. coli. Cavsol folds correctly and binds to its known protein ligands HIV gp41, the catalytic domain of cAMP-dependent protein kinase A, and the polymerase I and transcript release factor. As expected, cavsol does not bind off-target proteins. Cellular studies show that cavsol retains the parent protein's ability to localize at the cellular membrane. Unlike truncated versions of caveolin, cavsol forms large, oligomeric complexes consisting of approximately >50 monomeric units without requiring additional cellular components. Cavsol's secondary structure is a mixture of α-helices and β-strands. Isothermal titration calorimetry experiments reveal that cavsol binds to gp41 and PKA with low micromolar binding affinity (KD). In addition to the insights into caveolin structure and function, the approach applied here could be generalized to other membrane proteins.
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Affiliation(s)
- Joshua N Smith
- Department of Molecular Biology and Biochemistry,University of California, Irvine, CA 92697, USA
| | - Joshua M Edgar
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - J Mark Balk
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Mariam Iftikhar
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Jessica C Fong
- Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA
| | - Tivoli J Olsen
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Dmitry A Fishman
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Sudipta Majumdar
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Gregory A Weiss
- Department of Molecular Biology and Biochemistry,University of California, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, CA 92697, USA.
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Thangavel S, Mulet CT, Atluri VSR, Agudelo M, Rosenberg R, Devieux JG, Nair MPN. Oxidative Stress in HIV Infection and Alcohol Use: Role of Redox Signals in Modulation of Lipid Rafts and ATP-Binding Cassette Transporters. Antioxid Redox Signal 2018; 28:324-337. [PMID: 29132227 PMCID: PMC5743035 DOI: 10.1089/ars.2016.6830] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
AIMS Human immunodeficiency virus (HIV) infection induces oxidative stress and alcohol use accelerates disease progression, subsequently causing immune dysfunction. However, HIV and alcohol impact on lipid rafts-mediated immune dysfunction remains unknown. In this study, we investigate the modulation by which oxidative stress induces reactive oxygen species (ROS) affecting redox expression, lipid rafts caveiloin-1, ATP-binding cassette (ABC) transporters, and transcriptional sterol regulatory element-binding protein (SREBP) gene and protein modification and how these mechanisms are associated with arachidonic acid (AA) metabolites in HIV positive alcohol users, and how they escalate immune dysfunction. RESULTS In both alcohol using HIV-positive human subjects and in vitro studies of alcohol with HIV-1 gp120 protein in peripheral blood mononuclear cells, increased ROS production significantly affected redox expression in glutathione synthetase (GSS), super oxide dismutase (SOD), and glutathione peroxidase (GPx), and subsequently impacted lipid rafts Cav-1, ABC transporters ABCA1, ABCG1, ABCB1, and ABCG4, and SREBP transcription. The increased level of rate-limiting enzyme 3-hydroxy-3-methylglutaryl HMG-CoA reductase (HMGCR), subsequently, inhibited 7-dehydrocholesterol reductase (DHCR-7). Moreover, the expression of cyclooxygenase-2 (COX-2) and lipoxygenase-5 (5-LOX) mRNA and protein modification tentatively increased the levels of prostaglandin E2 synthases (PGE2) in plasma when compared with either HIV or alcohol alone. INNOVATION This article suggests for the first time that the redox inhibition affects lipid rafts, ABC-transporter, and SREBP transcription and modulates AA metabolites, serving as an important intermediate signaling network during immune cell dysfunction in HIV-positive alcohol users. CONCLUSION These findings indicate that HIV infection induces oxidative stress and redox inhibition, affecting lipid rafts and ABC transports, subsequently upregulating AA metabolites and leading to immune toxicity, and further exacerbation with alcohol use. Antioxid. Redox Signal. 28, 324-337.
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Affiliation(s)
- Samikkannu Thangavel
- 1 Department of Immunology, Institute of NeuroImmune Pharmacology, College of Medicine, Florida International University , Miami, Florida
| | - Carmen T Mulet
- 1 Department of Immunology, Institute of NeuroImmune Pharmacology, College of Medicine, Florida International University , Miami, Florida
| | - Venkata S R Atluri
- 1 Department of Immunology, Institute of NeuroImmune Pharmacology, College of Medicine, Florida International University , Miami, Florida
| | - Marisela Agudelo
- 1 Department of Immunology, Institute of NeuroImmune Pharmacology, College of Medicine, Florida International University , Miami, Florida
| | - Rhonda Rosenberg
- 2 Department of Health Promotion & Disease Prevention, Robert Stempel School of Public Health, Florida International University , Miami, Florida
| | - Jessy G Devieux
- 2 Department of Health Promotion & Disease Prevention, Robert Stempel School of Public Health, Florida International University , Miami, Florida
| | - Madhavan P N Nair
- 1 Department of Immunology, Institute of NeuroImmune Pharmacology, College of Medicine, Florida International University , Miami, Florida
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7
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Udayantha HMV, Bathige SDNK, Priyathilaka TT, Lee S, Kim MJ, Lee J. Identification and characterization of molluscan caveolin-1 ortholog from Haliotis discus discus: Possible involvement in embryogenesis and host defense mechanism against pathogenic stress. Gene Expr Patterns 2017; 27:85-92. [PMID: 29128397 DOI: 10.1016/j.gep.2017.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/13/2017] [Accepted: 11/06/2017] [Indexed: 02/05/2023]
Abstract
Caveolins are principal membrane proteins of caveolae that play a central role in signal transduction, substrate transport, and membrane trafficking in various cell types. Numerous studies have reported the crucial role of caveolin-1 (CAV1) in response to invading microbes; yet, very little is known about molluscan CAV1. In this study, we identified and characterized CAV1 ortholog from the disk abalone, Haliotis discus discus (HdCAV1). The cDNA sequence of HdCAV1 is 826 bp long and encodes a 127-amino acid polypeptide. Characteristic caveolin superfamily domain (Glu3 - Lys126) and two possible transmembrane domains (Cys48 - Tyr67 and Ile103 - Phe120) were identified in the HdCAV1 protein. Homology analysis revealed that HdCAV1 shared higher identity (>47%) with molluscans, but lower identity with other species. Phylogenetic tree constructed by the neighbor-joining (NJ) method revealed a distinct evolutionary pathway for molluscans. Transcriptional analysis by SYBR Green qPCR showed the highest expression of HdCAV1 mRNA in late veliger stage, as compared to that in other embryonic developmental stages of disk abalone. In adult animals, gill tissue showed highest HdCAV1 transcript levels under normal physiological condition. Stimulations with two bacteria (Vibrio parahaemolyticus and Listeria monocytogenes), viral hemorrhagic septicemia virus, and two pathogen-associated molecular patterns (LPS and poly I:C) significantly modulated the expression of HdCAV1 transcripts. Collectively, these data suggest that CAV1 plays an important role in embryogenesis and host immune defense in disk abalone.
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Affiliation(s)
- H M V Udayantha
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Department of Fisheries and Aquaculture, Faculty of Fisheries and Marine Sciences and Technology, University of Ruhuna, Matara, Sri Lanka
| | - S D N K Bathige
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Mahenwatta, Pitipana, Homagama, Sri Lanka
| | - Thanthrige Thiunuwan Priyathilaka
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea
| | - Sukkyoung Lee
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea
| | - Myoung-Jin Kim
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea.
| | - Jehee Lee
- Department of Marine Life Sciences, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea.
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8
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Garg H, Joshi A. Host and Viral Factors in HIV-Mediated Bystander Apoptosis. Viruses 2017; 9:v9080237. [PMID: 28829402 PMCID: PMC5579491 DOI: 10.3390/v9080237] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/14/2017] [Accepted: 08/16/2017] [Indexed: 02/07/2023] Open
Abstract
Human immunodeficiency virus (HIV) infections lead to a progressive loss of CD4 T cells primarily via the process of apoptosis. With a limited number of infected cells and vastly disproportionate apoptosis in HIV infected patients, it is believed that apoptosis of uninfected bystander cells plays a significant role in this process. Disease progression in HIV infected individuals is highly variable suggesting that both host and viral factors may influence HIV mediated apoptosis. Amongst the viral factors, the role of Envelope (Env) glycoprotein in bystander apoptosis is well documented. Recent evidence on the variability in apoptosis induction by primary patient derived Envs underscores the role of Env glycoprotein in HIV disease. Amongst the host factors, the role of C-C Chemokine Receptor type 5 (CCR5), a coreceptor for HIV Env, is also becoming increasingly evident. Polymorphisms in the CCR5 gene and promoter affect CCR5 cell surface expression and correlate with both apoptosis and CD4 loss. Finally, chronic immune activation in HIV infections induces multiple defects in the immune system and has recently been shown to accelerate HIV Env mediated CD4 apoptosis. Consequently, those factors that affect CCR5 expression and/or immune activation in turn indirectly regulate HIV mediated apoptosis making this phenomenon both complex and multifactorial. This review explores the complex role of various host and viral factors in determining HIV mediated bystander apoptosis.
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Affiliation(s)
- Himanshu Garg
- Center of Emphasis in Infectious Diseases, Department of Biomedical Sciences, Texas Tech University Health Sciences Center, 5001 El Paso Dr., El Paso, TX 79905, USA.
| | - Anjali Joshi
- Center of Emphasis in Infectious Diseases, Department of Biomedical Sciences, Texas Tech University Health Sciences Center, 5001 El Paso Dr., El Paso, TX 79905, USA.
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9
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The Role of Caveolin 1 in HIV Infection and Pathogenesis. Viruses 2017; 9:v9060129. [PMID: 28587148 PMCID: PMC5490806 DOI: 10.3390/v9060129] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/02/2017] [Accepted: 05/22/2017] [Indexed: 12/29/2022] Open
Abstract
Caveolin 1 (Cav-1) is a major component of the caveolae structure and is expressed in a variety of cell types including macrophages, which are susceptible to human immunodeficiency virus (HIV) infection. Caveolae structures are present in abundance in mechanically stressed cells such as endothelial cells and adipocytes. HIV infection induces dysfunction of these cells and promotes pathogenesis. Cav-1 and the caveolae structure are believed to be involved in multiple cellular processes that include signal transduction, lipid regulation, endocytosis, transcytosis, and mechanoprotection. Such a broad biological role of Cav-1/caveolae is bound to have functional cross relationships with several molecular pathways including HIV replication and viral-induced pathogenesis. The current review covers the relationship of Cav-1 and HIV in respect to viral replication, persistence, and the potential role in pathogenesis.
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10
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Selvan LDN, Sreenivasamurthy SK, Kumar S, Yelamanchi SD, Madugundu AK, Anil AK, Renuse S, Nair BG, Gowda H, Mathur PP, Satishchandra P, Shankar SK, Mahadevan A, Keshava Prasad TS. Characterization of host response to Cryptococcus neoformans through quantitative proteomic analysis of cryptococcal meningitis co-infected with HIV. MOLECULAR BIOSYSTEMS 2016; 11:2529-40. [PMID: 26181685 DOI: 10.1039/c5mb00187k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cryptococcal meningitis is the most common opportunistic fungal infection causing morbidity and mortality (>60%) in HIV-associated immunocompromised individuals caused by Cryptococcus neoformans. Molecular mechanisms of cryptococcal infection in brain have been studied using experimental animal models and cell lines. There are limited studies for the molecular understanding of cryptococcal meningitis in human brain. The proteins involved in the process of invasion and infection in human brain still remains obscure. To this end we carried out mass spectrometry-based quantitative proteomics of frontal lobe brain tissues from cryptococcal meningitis patients and controls to identify host proteins that are associated with the pathogenesis of cryptococcal meningitis. We identified 317 proteins to be differentially expressed (≥2-fold) from a total of 3423 human proteins. We found proteins involved in immune response and signal transduction to be differentially expressed in response to cryptococcal infection in human brain. Immune response proteins including complement factors, major histocompatibility proteins, proteins previously known to be involved in fungal invasion to brain such as caveolin 1 and actin were identified to be differentially expressed in cryptococcal meningitis brain tissues co-infected with HIV. We also validated the expression status of 5 proteins using immunohistochemistry. Overexpression of major histocompatibility complexes, class I, B (HLA-B), actin alpha 2 smooth muscle aorta (ACTA2) and caveolin 1 (CAV1) and downregulation of peripheral myelin protein 2 (PMP2) and alpha crystallin B chain (CRYAB) in cryptococcal meningitis were confirmed by IHC-based validation experiments. This study provides the brain proteome profile of cryptococcal meningitis co-infected with HIV for a better understanding of the host response associated with the disease.
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Lim JS, Nguyen KCT, Nguyen CT, Jang I, Han JM, Fabian C, Lee SE, Rhee JH, Cho KA. Flagellin-dependent TLR5/caveolin-1 as a promising immune activator in immunosenescence. Aging Cell 2015. [PMID: 26223660 PMCID: PMC4568978 DOI: 10.1111/acel.12383] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The age-associated decline of immune responses causes high susceptibility to infections and reduced vaccine efficacy in the elderly. However, the mechanisms underlying age-related deficits are unclear. Here, we found that the expression and signaling of flagellin (FlaB)-dependent Toll-like receptor 5 (TLR5), unlike the other TLRs, were well maintained in old macrophages, similar to young macrophages. The expression and activation of TLR5/MyD88, but not TLR4, were sensitively regulated by the upregulation of caveolin-1 in old macrophages through direct interaction. This interaction was also confirmed using macrophages from caveolin-1 or MyD88 knockout mice. Because TLR5 and caveolin-1 were well expressed in major old tissues including lung, skin, intestine, and spleen, we analyzed in vivo immune responses via a vaccine platform with FlaB as a mucosal adjuvant for the pneumococcal surface protein A (PspA) against Streptococcus pneumoniae infection in young and aged mice. The FlaB-PspA fusion protein induced a significantly higher level of PspA-specific IgG and IgA responses and demonstrated a high protective efficacy against a lethal challenge with live S. pneumoniae in aged mice. These results suggest that caveolin-1/TLR5 signaling plays a key role in age-associated innate immune responses and that FlaB-PspA stimulation of TLR5 may be a new strategy for a mucosal vaccine adjuvant against pneumococcal infection in the elderly.
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Affiliation(s)
- Jae Sung Lim
- Department of Biochemistry Chonnam National University Medical School Gwangju 501‐746 South Korea
| | - Kim Cuc Thi Nguyen
- Department of Biochemistry Chonnam National University Medical School Gwangju 501‐746 South Korea
- Center for Creative Biomedical Scientists Chonnam National University Medical School Gwangju 501‐746 South Korea
| | - Chung Truong Nguyen
- Clinical Vaccine R&D Center Chonnam National University Hwasun Hospital 160 Ilsim‐Ri Hwasun‐gun Jeonnam 519‐809 South Korea
| | - Ik‐Soon Jang
- Division of Life Science Korea Basic Science Institute Daejeon 305‐333 South Korea
| | - Jung Min Han
- Department of Integrated OMICS for Biomedical Science Yonsei University Seoul 120‐749 South Korea
- College of Pharmacy Yonsei University Incheon 406‐840 South Korea
| | - Claire Fabian
- Department of Immunology Fraunhofer Institute for Cell Therapy and Immunology (IZI) University of Leipzig 04103 Leipzig Germany
- Translational Center for Regenerative Medicine (TRM) University of Leipzig 04103 Leipzig Germany
| | - Shee Eun Lee
- Clinical Vaccine R&D Center Chonnam National University Hwasun Hospital 160 Ilsim‐Ri Hwasun‐gun Jeonnam 519‐809 South Korea
- Dental Science Research Institute School of Dentistry Chonnam National University Gwangju 500‐757 South Korea
| | - Joon Haeng Rhee
- Clinical Vaccine R&D Center Chonnam National University Hwasun Hospital 160 Ilsim‐Ri Hwasun‐gun Jeonnam 519‐809 South Korea
- Department of Microbiology Chonnam National University Medical School Gwangju 501‐746 South Korea
| | - Kyung A Cho
- Department of Biochemistry Chonnam National University Medical School Gwangju 501‐746 South Korea
- Center for Creative Biomedical Scientists Chonnam National University Medical School Gwangju 501‐746 South Korea
- Clinical Vaccine R&D Center Chonnam National University Hwasun Hospital 160 Ilsim‐Ri Hwasun‐gun Jeonnam 519‐809 South Korea
- Research Institute of Medical Sciences Chonnam National University Medical School Gwangju 501‐746 South Korea
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12
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Lin S, Nadeau PE, Mergia A. HIV inhibits endothelial reverse cholesterol transport through impacting subcellular Caveolin-1 trafficking. Retrovirology 2015; 12:62. [PMID: 26169283 PMCID: PMC4501058 DOI: 10.1186/s12977-015-0188-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 07/06/2015] [Indexed: 01/13/2023] Open
Abstract
Background Human immunodeficiency virus (HIV) infection leads to decreased reverse cholesterol transport (RCT) in macrophages, and Nef mediated down-regulation and redistribution of ATP-binding cassette transporter A1 (ABCA1) are identified as key factors for this effect. This may partially explain the increased risk of atherosclerosis in HIV infected individuals. Since endothelial dysfunction is key in the initial stages of atherosclerosis, we sought to determine whether RCT was affected in human aortic endothelial cells (HAECs). Results We found that apoA-I does not significantly stimulate cholesterol efflux in HAECs while cholesterol efflux to high-density lipoprotein (HDL) was dramatically reduced in HAECs co-cultured with HIV infected cells. Studies with wild type and Nef defective HIV revealed no significant differences suggesting that multiple factors are working perhaps in concert with Nef to affect cholesterol efflux to HDL from HAECs. Interestingly, treating HAECs with recombinant Nef showed similar effect in HDL mediated cholesterol efflux as observed in HAECs co-cultured with HIV infected cells. Using a detergent-free based subcellular fractionation approach, we demonstrated that exposure of HAECs to HIV infected cells or Nef alone disrupts caveolin 1 (Cav-1) subcellular trafficking upon HDL stimulation. Moreover, Nef significantly enhanced tyrosine 14 phosphorylation of Cav-1 which may have an impact on recycling of Cav-1 and caveolae. Conclusion These results suggest that HIV interferes with cholesterol efflux by HDL in HAECs through the disruption of Cav-1s’ cellular distribution and that multiple factors are involved, possibly including Nef, for the inhibition of HDL mediated cholesterol efflux and alteration of cellular distribution of Cav-1. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0188-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shanshan Lin
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, 32611, USA.
| | - Peter E Nadeau
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, 32611, USA.
| | - Ayalew Mergia
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, 32611, USA.
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Yuan TZ, Ormonde CFG, Kudlacek ST, Kunche S, Smith JN, Brown WA, Pugliese KM, Olsen TJ, Iftikhar M, Raston CL, Weiss GA. Shear-stress-mediated refolding of proteins from aggregates and inclusion bodies. Chembiochem 2015; 16:393-6. [PMID: 25620679 DOI: 10.1002/cbic.201402427] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 12/01/2014] [Indexed: 11/12/2022]
Abstract
Recombinant protein overexpression of large proteins in bacteria often results in insoluble and misfolded proteins directed to inclusion bodies. We report the application of shear stress in micrometer-wide, thin fluid films to refold boiled hen egg white lysozyme, recombinant hen egg white lysozyme, and recombinant caveolin-1. Furthermore, the approach allowed refolding of a much larger protein, cAMP-dependent protein kinase A (PKA). The reported methods require only minutes, which is more than 100 times faster than conventional overnight dialysis. This rapid refolding technique could significantly shorten times, lower costs, and reduce waste streams associated with protein expression for a wide range of industrial and research applications.
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Affiliation(s)
- Tom Z Yuan
- University of California, Irvine, Department of Molecular Biology and Biochemistry, Irvine, CA, 92697-2025 (USA)
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Lo YT, Nadeau PE, Lin S, Mergia A. Establishing Restricted Expression of Caveolin-1 in HIV Infected Cells and Inhibition of Virus Replication. Open Microbiol J 2014; 8:114-21. [PMID: 25408776 PMCID: PMC4235073 DOI: 10.2174/1874285801408010114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 09/22/2014] [Accepted: 10/02/2014] [Indexed: 11/22/2022] Open
Abstract
Background: Caveolin-1 (Cav-1) is the major protein of the caveolae and plays a role in multiple cellular functions and implicated to have anti-HIV activity. Regulated expression of Cav-1 is important for safe and effective use in order to exploit Cav-1 for HIV therapeutic applications. Methods: A series of Cav-1 and GFP expression vectors were constructed under the control of the HIV LTR for conditional expression or CMV promoter and the expression of Cav-1 was monitored in the presence or absence of Tat or HIV infection in order to establish the restricted expression of Cav-1 to HIV infected cells. Results: Cav-1 expression was evident under the control of the HIV LTR in the absence of Tat or HIV infection as demonstrated by immunoblot. Placing two internal ribosomal entry sequences (IRES) and a Rev response element, RRE (5’~ LTR-IRES-GFP-RRE-IRES-Cav-1~3’) resulted in no expression of Cav-1 in the absence of Tat with effective expression in the presence of Tat. Transduction of HIV permissive cells with this construct using a foamy virus vector show that Cav-1 was able to inhibit HIV replication by 82%. Cells that received LTR-IRES-GFP-RRE-IRES-Cav-1 remain healthy in the absence of Tat or HIV infection. Conclusion: These results taken together reveal the inclusion of two IRES establishes a significant reduction of leak through expression of Cav-1 in the absence of Tat or HIV infection. Such regulated expression will have therapeutic application of Cav-1 for HIV infection as well as broad applications which can be beneficial for other host-targeted interventions as therapeutics.
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Affiliation(s)
- Yung-Tsun Lo
- Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA
| | - Peter E Nadeau
- Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA
| | - Shanshan Lin
- Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA
| | - Ayalew Mergia
- Department of Infectious Disease and Pathology, University of Florida, Gainesville, FL 32611, USA
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Identification of molecular sub-networks associated with cell survival in a chronically SIVmac-infected human CD4+ T cell line. Virol J 2014; 11:152. [PMID: 25163480 PMCID: PMC4163169 DOI: 10.1186/1743-422x-11-152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 08/15/2014] [Indexed: 12/31/2022] Open
Abstract
Background The deciphering of cellular networks to determine susceptibility to infection by HIV or the related simian immunodeficiency virus (SIV) is a major challenge in infection biology. Results Here, we have compared gene expression profiles of a human CD4+ T cell line at 24 h after infection with a cell line of the same origin permanently releasing SIVmac. A new knowledge-based-network approach (Inter-Chain-Finder, ICF) has been used to identify sub-networks associated with cell survival of a chronically SIV-infected T cell line. Notably, the method can identify not only differentially expressed key hub genes but also non-differentially expressed, critical, ‘hidden’ regulators. Six out of the 13 predicted major hidden key regulators were among the landscape of proteins known to interact with HIV. Several sub-networks were dysregulated upon chronic infection with SIV. Most prominently, factors reported to be engaged in early stages of acute viral infection were affected, e.g. entry, integration and provirus transcription and other cellular responses such as apoptosis and proliferation were modulated. For experimental validation of the gene expression analyses and computational predictions, individual pathways/sub-networks and significantly altered key regulators were investigated further. We showed that the expression of caveolin-1 (Cav-1), the top hub in the affected protein-protein interaction network, was significantly upregulated in chronically SIV-infected CD4+ T cells. Cav-1 is the main determinant of caveolae and a central component of several signal transduction pathways. Furthermore, CD4 downregulation and modulation of the expression of alternate and co-receptors as well as pathways associated with viral integration into the genome were also observed in these cells. Putatively, these modifications interfere with re-infection and the early replication cycle and inhibit cell death provoked by syncytia formation and bystander apoptosis. Conclusions Thus, by using the novel approach for network analysis, ICF, we predict that in the T cell line chronically infected with SIV, cellular processes that are known to be crucial for early phases of HIV/SIV replication are altered and cellular responses that result in cell death are modulated. These modifications presumably contribute to cell survival despite chronic infection. Electronic supplementary material The online version of this article (doi:10.1186/1743-422X-11-152) contains supplementary material, which is available to authorized users.
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Abstract
Apoptosis of uninfected bystander cells is a key element of HIV pathogenesis and believed to be the driving force behind the selective depletion of CD4+ T cells leading to immunodeficiency. While several viral proteins have been implicated in this process the complex interaction between Env glycoprotein expressed on the surface of infected cells and the receptor and co-receptor expressing bystander cells has been proposed as a major mechanism. HIV-1 utilizes CD4 as the primary receptor for entry into cells; however, it is the viral co-receptor usage that greatly influences CD4 decline and progression to AIDS. This phenomenon is relatively simple for X4 viruses, which arise later during the course of the disease, are considered to be highly fusogenic, and cause a rapid CD4+ T cell decline. However, in contrast, R5 viruses in general have a greater transmissibility, are encountered early during the disease and have a lesser pathogenic potential than the former. The above generalization gets complicated in numerous situations where R5 viruses persist throughout the disease and are capable of causing a rigorous CD4+ T cell decline. This review will discuss the multiple factors that are reported to influence HIV induced bystander apoptosis and pathogenesis including Env glycoprotein phenotype, virus tropism, disease stage, co-receptor expression on CD4+ T cells, immune activation and therapies targeting the viral envelope.
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Affiliation(s)
- Himanshu Garg
- Center of Excellence for Infectious Disease, Department of Biomedical Science, Texas Tech University Health Sciences Center, 5001 El Paso Dr, MSB-1 Annex, El Paso, TX 79905, USA.
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Lin S, Nadeau PE, Wang X, Mergia A. Caveolin-1 reduces HIV-1 infectivity by restoration of HIV Nef mediated impairment of cholesterol efflux by apoA-I. Retrovirology 2012; 9:85. [PMID: 23067370 PMCID: PMC3487900 DOI: 10.1186/1742-4690-9-85] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/26/2012] [Indexed: 11/12/2022] Open
Abstract
Background HIV infection results in inhibited cholesterol efflux by apolipoprotein A-I (apoA-I) in macrophages, and this impairment involves Nef mediated down-regulation and redistribution of ATP-binding cassette transporter A1 (ABCA-1). We investigated the effect of caveolin-1 (Cav-1) on the cholesterol efflux by apoA-I in HIV infected primary and THP-1 cell-differentiated macrophages as well as astrocyte derived glioblastoma U87 cells. Results Our results reveal that Cav-1 restores the Nef -mediated impairment of cholesterol efflux by apoA-I in both cell types. Co-immunoprecipitation studies indicate a physical association of Cav-1 and Nef. The level of ABCA-1 expression remains the same whether Cav-1 is over-expressed or not. In addition, we examined the cholesterol composition of HIV particles released from Cav-1 treated cells and identified that the cholesterol content is dramatically reduced. The infectivity level of these virus particles is also significantly decreased. Conclusions These observations suggest that the interplay of Cav-1 with Nef and cholesterol subsequently counters Nef induced impairment of cholesterol efflux by apoA-l. The findings provide a cellular mechanism by which Cav-1 has an ability to restore HIV mediated impairment of cholesterol efflux in macrophages. This subsequently influences the cholesterol content incorporated into virus particles thereby inhibiting HIV infectivity and contributing to HIV’s persistent infection of macrophages.
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Affiliation(s)
- Shanshan Lin
- Department of Infectious Disease and Pathology, University of Florida, Gainesville, Florida, 32611, USA
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Guo Q, Shen N, Yuan K, Li J, Wu H, Zeng Y, Fox J, Bansal AK, Singh BB, Gao H, Wu M. Caveolin-1 plays a critical role in host immunity against Klebsiella pneumoniae by regulating STAT5 and Akt activity. Eur J Immunol 2012; 42:1500-11. [PMID: 22678904 DOI: 10.1002/eji.201142051] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Caveolin-1 (Cav1) is a structural protein of caveolae. Although Cav1 is associated with certain bacterial infections, it is unknown whether Cav1 is involved in host immunity against Klebsiella pneumoniae, the third most commonly isolated microorganism from bacterial sepsis patients. Here, we showed that cav1 knockout mice succumbed to K. pneumoniae infection with markedly decreased survival rates, increased bacterial burdens, intensified tissue injury, hyperactive proinflammatory cytokines, and systemic bacterial dissemination as compared with WT mice. Knocking down Cav1 by a dominant negative approach in lung epithelial MLE-12 cells resulted in similar outcomes (decreased bacterial clearance and increased proinflammatory cytokine production). Furthermore, we revealed that STAT5 influences the GSK3β-β-catenin-Akt pathway, which contributes to the intensive inflammatory response and rapid infection dissemination seen in Cav1 deficiency. Collectively, our findings indicate that Cav1 may offer resistance to K. pneumoniae infection, by affecting both systemic and local production of proinflammatory cytokines via the actions of STAT5 and the GSK3β-β-catenin-Akt pathway.
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Affiliation(s)
- Qiang Guo
- Department of Biochemistry and Molecular Biology, University of North Dakota, Grand Forks, North Dakota 58203, USA
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Caveolin-1 suppresses human immunodeficiency virus-1 replication by inhibiting acetylation of NF-κB. Virology 2012; 432:110-9. [PMID: 22748181 DOI: 10.1016/j.virol.2012.05.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 03/24/2012] [Accepted: 05/22/2012] [Indexed: 12/22/2022]
Abstract
Caveolin-1 is an integral membrane protein primarily responsible for the formation of membrane structures known as caveolae. Caveolae are specialized lipid rafts involved in protein trafficking, cholesterol homeostasis, and a number of signaling functions. It has been demonstrated that caveolin-1 suppresses HIV-1 protein expression. We found that co-transfecting cells with HIV-1 and caveolin-1 constructs, results in a marked decrease in the level of HIV-1 transcription relative to cells transfected with HIV-1 DNA alone. Correspondingly, reduction of endogenous caveolin-1 expression by siRNA-mediated silencing resulted in an enhancement of HIV-1 replication. Further, we observed a loss of caveolin-mediated suppression of HIV-1 transcription in promoter studies with reporters containing mutations in the NF-κB binding site. Our analysis of the posttranslational modification status of the p65 subunit of NF-κB demonstrates hypoacetylation of p65 in the presence of caveolin-1. Since hypoacetylated p65 has been shown to inhibit transcription, we conclude that caveolin-1 inhibits HIV-1 transcription through a NF-κB-dependent mechanism.
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Cunyat F, Marfil S, García E, Svicher V, Pérez-Alvárez N, Curriu M, Perno CF, Clotet B, Blanco J, Cabrera C. The HR2 polymorphism N140I in the HIV-1 gp41 combined with the HR1 V38A mutation is associated with a less cytopathic phenotype. Retrovirology 2012; 9:15. [PMID: 22333046 PMCID: PMC3312827 DOI: 10.1186/1742-4690-9-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 02/14/2012] [Indexed: 12/11/2022] Open
Abstract
Background Resistance to the fusion inhibitor enfuvirtide (ENF) is achieved by changes in the gp41 subunit of the HIV envelope glycoprotein (Env). Specific ENF-associated mutational pathways correlate with immunological recovery, even after virological failure, suggesting that the acquisition of ENF resistance alters gp41 pathogenicity. To test this hypothesis, we have characterized the expression, fusion capability, induction of CD4+ T cell loss and single CD4+ T cell death of 48 gp41 proteins derived from three patients displaying different amino acids (N, T or I) at position 140 that developed a V38A mutation after ENF-based treatment. Results In all cases, intra-patient comparison of Env isolated pre- or post-treatment showed comparable values of expression and fusogenic capacity. Furthermore, Env with either N or T at position 140 induced comparable losses of CD4+ T-cells, irrespective of the residue present at position 38. Conversely, Env acquiring the V38A mutation in a 140I background induced a significantly reduced loss of CD4+ T cells and lower single-cell death than did their baseline controls. No altered ability to induce single-cell death was observed in the other clones. Conclusions Overall, primary gp41 proteins with both V38A and N140I changes showed a reduced ability to induce single cell death and deplete CD4+ T cells, despite maintaining fusion activity. The specificity of this phenotype highlights the relevance of the genetic context to the cytopathic capacity of Env and the role of ENF-resistance mutations in modulating viral pathogenicity in vivo, further supporting the hypothesis that gp41 is a critical mediator of HIV pathogenesis.
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Affiliation(s)
- Francesc Cunyat
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Catalonia, Spain.
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Mo S, Yang S, Cui Z. New glimpses of caveolin-1 functions in embryonic development and human diseases. FRONTIERS IN BIOLOGY 2011; 6:367. [PMID: 32215005 PMCID: PMC7089126 DOI: 10.1007/s11515-011-1132-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 12/30/2010] [Indexed: 11/17/2022]
Abstract
Caveolin-1 (Cav-1) isoforms, including Cav-1α and Cav-1β, were identified as integral membrane proteins and the major components of caveolae. Cav-1 proteins are highly conserved during evolution from {itCaenorhabditis elegans} to human and are capable of interacting with many signaling molecules through their caveolin scaffolding domains to regulate the activities of multiple signaling pathways. Thus, Cav-1 plays crucial roles in the regulation of cellular proliferation, differentiation and apoptosis in a cell-specific and contextual manner. In addition, Cav-1 is essential for embryonic development of vertebrates owing to its regulation of BMP, Wnt, TGF-β and other key signaling molecules. Moreover, Cav-1 is mainly expressed in terminally differentiated cells and its abnormal expression is often associated with human diseases, such as tumor progression, cardiovascular diseases, fibrosis, lung regeneration, and diseases related to virus. In this review, we will further discuss the potential of Cav-1 as a target for disease therapy and multiple drug resistance.
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Affiliation(s)
- Saijun Mo
- Department of Basic Oncology, College of Basic Medical Sciences, Zhengzhou University, Zhengzhou, 450001 China
| | - Shengli Yang
- Department of Basic Oncology, College of Basic Medical Sciences, Zhengzhou University, Zhengzhou, 450001 China
| | - Zongbin Cui
- Key Laboratory of Biodiversity and Conservation of Aquatic Organism, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072 China
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Caveolin 1 inhibits HIV replication by transcriptional repression mediated through NF-κB. J Virol 2011; 85:5483-93. [PMID: 21430048 DOI: 10.1128/jvi.00254-11] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Caveolin 1 (Cav-1), the scaffold protein of a specific membrane lipid raft called caveolae, has been reported to suppress HIV-1 replication. However, the mechanism by which Cav-1 inhibits HIV replication remains unclear. In this study, we investigated the mechanism by which Cav-1 inhibits HIV replication at the level of gene expression. Our results show that Cav-1 represses viral gene expression and that this suppression involves the NF-κB pathway. We used several approaches in different cell types, including primary CD4(+) T cells and macrophages, to demonstrate the role of nuclear factor κB (NF-κB) in Cav-1-mediated inhibition of viral expression. A mutational analysis of the cis-acting element shows that the two NF-κB sites in the U3 region of the long terminal repeat (LTR) are critical for Cav-1-mediated inhibition of viral expression. In the presence of Cav-1, phosphorylation of IKKβ, IKKα, IκBα, and NF-κB p65 is dramatically reduced, while viral gene expression is suppressed. In addition, translocation of NF-κB p65 to the nucleus decreases substantially in the presence of Cav-1. Furthermore, significant inhibition of NF-κB activation and binding to target DNA are evident in the presence of Cav-1. These results establish evidence that Cav-1 inhibits HIV replication by transcriptional repression of viral gene expression and contributes to HIV's persistent infection of macrophages.
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Abstract
Caveolin 1 (Cav-1) is a major protein of a specific membrane lipid raft known as caveolae. Cav-1 interacts with the gp41 of the human immunodeficiency virus (HIV) envelope, but the role of Cav-1 in HIV replication and pathogenesis is not known. In this report, we demonstrate that HIV infection in primary human monocyte-derived macrophages (MDMs), THP-1 macrophages, and U87-CD4 cells results in a dramatic upregulation of Cav-1 expression mediated by HIV Tat. The activity of p53 is essential for Tat-induced Cav-1 expression, as our findings show enhanced phosphorylation of serine residues at amino acid positions 15 and 46 in the presence of Tat with a resulting Cav-1 upregulation. Furthermore, inhibition of p38 mitogen-activated protein kinase (MAPK) blocked phosphorylation of p53 in the presence of Tat. Infection studies of Cav-1-overexpressing cells reveal a significant reduction of HIV production. Taken together, these results suggest that HIV infection enhances the expression of Cav-1, which subsequently causes virus reduction, suggesting that Cav-1 may contribute to persistent infection in macrophages.
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