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Ramirez Bustamante CE, Agarwal N, Cox AR, Hartig SM, Lake JE, Balasubramanyam A. Adipose Tissue Dysfunction and Energy Balance Paradigms in People Living With HIV. Endocr Rev 2024; 45:190-209. [PMID: 37556371 PMCID: PMC10911955 DOI: 10.1210/endrev/bnad028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 07/09/2023] [Accepted: 08/07/2023] [Indexed: 08/11/2023]
Abstract
Over the past 4 decades, the clinical care of people living with HIV (PLWH) evolved from treatment of acute opportunistic infections to the management of chronic, noncommunicable comorbidities. Concurrently, our understanding of adipose tissue function matured to acknowledge its important endocrine contributions to energy balance. PLWH experience changes in the mass and composition of adipose tissue depots before and after initiating antiretroviral therapy, including regional loss (lipoatrophy), gain (lipohypertrophy), or mixed lipodystrophy. These conditions may coexist with generalized obesity in PLWH and reflect disturbances of energy balance regulation caused by HIV persistence and antiretroviral therapy drugs. Adipocyte hypertrophy characterizes visceral and subcutaneous adipose tissue depot expansion, as well as ectopic lipid deposition that occurs diffusely in the liver, skeletal muscle, and heart. PLWH with excess visceral adipose tissue exhibit adipokine dysregulation coupled with increased insulin resistance, heightening their risk for cardiovascular disease above that of the HIV-negative population. However, conventional therapies are ineffective for the management of cardiometabolic risk in this patient population. Although the knowledge of complex cardiometabolic comorbidities in PLWH continues to expand, significant knowledge gaps remain. Ongoing studies aimed at understanding interorgan communication and energy balance provide insights into metabolic observations in PLWH and reveal potential therapeutic targets. Our review focuses on current knowledge and recent advances in HIV-associated adipose tissue dysfunction, highlights emerging adipokine paradigms, and describes critical mechanistic and clinical insights.
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Affiliation(s)
- Claudia E Ramirez Bustamante
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Neeti Agarwal
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Aaron R Cox
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sean M Hartig
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jordan E Lake
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School at UTHealth, Houston, TX 77030, USA
| | - Ashok Balasubramanyam
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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Shrivastav S, Lee H, Okamoto K, Lu H, Yoshida T, Latt KZ, Wakashin H, Dalgleish JLT, Koritzinsky EH, Xu P, Asico LD, Chung JY, Hewitt S, Gildea JJ, Felder RA, Jose PA, Rosenberg AZ, Knepper MA, Kino T, Kopp JB. HIV-1 Vpr suppresses expression of the thiazide-sensitive sodium chloride co-transporter in the distal convoluted tubule. PLoS One 2022; 17:e0273313. [PMID: 36129874 PMCID: PMC9491550 DOI: 10.1371/journal.pone.0273313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/07/2022] [Indexed: 11/19/2022] Open
Abstract
HIV-associated nephropathy (HIVAN) impairs functions of both glomeruli and tubules. Attention has been previously focused on the HIVAN glomerulopathy. Tubular injury has drawn increased attention because sodium wasting is common in hospitalized HIV/AIDS patients. We used viral protein R (Vpr)-transgenic mice to investigate the mechanisms whereby Vpr contributes to urinary sodium wasting. In phosphoenolpyruvate carboxykinase promoter-driven Vpr-transgenic mice, in situ hybridization showed that Vpr mRNA was expressed in all nephron segments, including the distal convoluted tubule. Vpr-transgenic mice, compared with wild-type littermates, markedly increased urinary sodium excretion, despite similar plasma renin activity and aldosterone levels. Kidneys from Vpr-transgenic mice also markedly reduced protein abundance of the Na+-Cl- cotransporter (NCC), while mineralocorticoid receptor (MR) protein expression level was unchanged. In African green monkey kidney cells, Vpr abrogated the aldosterone-mediated stimulation of MR transcriptional activity. Gene expression of Slc12a3 (NCC) in Vpr-transgenic mice was significantly lower compared with wild-type mice, assessed by both qRT-PCR and RNAScope in situ hybridization analysis. Chromatin immunoprecipitation assays identified multiple MR response elements (MRE), located from 5 kb upstream of the transcription start site and extending to the third exon of the SLC12A3 gene. Mutation of MRE and SP1 sites in the SLC12A3 promoter region abrogated the transcriptional responses to aldosterone and Vpr, indicating that functional MRE and SP1 are required for the SLC12A3 gene suppression in response to Vpr. Thus, Vpr attenuates MR transcriptional activity and inhibits Slc12a3 transcription in the distal convoluted tubule and contributes to salt wasting in Vpr-transgenic mice.
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Affiliation(s)
- Shashi Shrivastav
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Hewang Lee
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Koji Okamoto
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Huiyan Lu
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Teruhiko Yoshida
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Khun Zaw Latt
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Hidefumi Wakashin
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - James L. T. Dalgleish
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Erik H. Koritzinsky
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Peng Xu
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Laureano D. Asico
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Joon-Yong Chung
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - Stephen Hewitt
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - John J. Gildea
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Robin A. Felder
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Pedro A. Jose
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Avi Z. Rosenberg
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
| | - Mark A. Knepper
- Epithelial Systems Biology Laboratory, Systems Biology Center, Division of Intramural Research, NHLBI, NIH, Bethesda, Maryland, United States of America
| | - Tomoshige Kino
- Laboratory for Molecular and Genomic Endocrinology, Division of Translational Medicine, Sidra Medicine, Doha, Qatar
| | - Jeffrey B. Kopp
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
- * E-mail:
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Atindaana E, Kissi-Twum A, Emery S, Burnett C, Pitcher J, Visser M, Kidd JM, Telesnitsky A. Bimodal Expression Patterns, and Not Viral Burst Sizes, Predict the Effects of Vpr on HIV-1 Proviral Populations in Jurkat Cells. mBio 2022; 13:e0374821. [PMID: 35384697 PMCID: PMC9040753 DOI: 10.1128/mbio.03748-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/28/2022] [Indexed: 11/29/2022] Open
Abstract
Integration site landscapes, clonal dynamics, and latency reversal with or without vpr were compared in HIV-1-infected Jurkat cell populations, and the properties of individual clones were defined. Clones differed in fractions of long terminal repeat (LTR)-active daughter cells, with some clones containing few to no LTR-active cells, while almost all cells were LTR active for others. Clones varied over 4 orders of magnitude in virus release per active cell. Proviruses in largely LTR-active clones were closer to preexisting enhancers and promoters than low-LTR-active clones. Unsurprisingly, major vpr+ clones contained fewer LTR-active cells than vpr- clones, and predominant vpr+ proviruses were farther from enhancers and promoters than those in vpr- pools. Distances to these marks among intact proviruses previously reported for antiretroviral therapy (ART)-suppressed patients revealed that patient integration sites were more similar to those in the vpr+ pool than to vpr- integrants. Complementing vpr-defective proviruses with vpr led to the rapid loss of highly LTR-active clones, indicating that the effect of Vpr on proviral populations occurred after integration. However, major clones in the complemented pool and its vpr- parent population did not differ in burst sizes. When the latency reactivation agents prostratin and JQ1 were applied separately or in combination, vpr+ and vpr- population-wide trends were similar, with dual-treatment enhancement being due in part to reactivated clones that did not respond to either drug applied separately. However, the expression signatures of individual clones differed between populations. These observations highlight how Vpr, exerting selective pressure on proviral epigenetic variation, can shape integration site landscapes, proviral expression patterns, and reactivation properties. IMPORTANCE A bedrock assumption in HIV-1 population modeling is that all active cells release the same amount of virus. However, the findings here revealed that when HIV-infected cells expand into clones, each clone differs in virus production. Reasoning that this variation in expression patterns constituted a population of clones from which differing subsets would prevail under differing environmental conditions, the cytotoxic HIV-1 protein Vpr was introduced, and population dynamics and expression properties were compared in the presence and absence of Vpr. The results showed that whereas most clones produced fairly continuous levels of virus in the absence of Vpr, its presence selected for a distinct subset of clones with properties reminiscent of persistent populations in patients, suggesting the possibility that the interclonal variation in expression patterns observed in culture may contribute to proviral persistence in vivo.
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Affiliation(s)
- Edmond Atindaana
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Abena Kissi-Twum
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Legon, Greater Accra Region, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Greater Accra Region, Ghana
| | - Sarah Emery
- Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Cleo Burnett
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jake Pitcher
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Myra Visser
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jeffrey M. Kidd
- Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Alice Telesnitsky
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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HIV-1 Tat Protein Promotes Neuroendocrine Dysfunction Concurrent with the Potentiation of Oxycodone's Psychomotor Effects in Female Mice. Viruses 2021; 13:v13050813. [PMID: 33946474 PMCID: PMC8147167 DOI: 10.3390/v13050813] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023] Open
Abstract
Human immunodeficiency virus (HIV) is associated with neuroendocrine dysfunction which may contribute to co-morbid stress-sensitive disorders. The hypothalamic-pituitary-adrenal (HPA) or -gonadal (HPG) axes are perturbed in up to 50% of HIV patients. The mechanisms are not known, but we have found the HIV-1 trans-activator of transcription (Tat) protein to recapitulate the clinical phenotype in male mice. We hypothesized that HPA and/or HPG dysregulation contributes to Tat-mediated interactions with oxycodone, an opioid often prescribed to HIV patients, in females. Female mice that conditionally-expressed the Tat1-86 protein [Tat(+) mice] or their counterparts that did not [Tat(-) control mice] were exposed to forced swim stress (or not) and behaviorally-assessed for motor and anxiety-like behavior. Some mice had glucocorticoid receptors (GR) or corticotropin-releasing factor receptors (CRF-R) pharmacologically inhibited. Some mice were ovariectomized (OVX). As seen previously in males, Tat elevated basal corticosterone levels and potentiated oxycodone's psychomotor activity in females. Unlike males, females did not demonstrate adrenal insufficiency and oxycodone potentiation was not regulated by GRs or CRF-Rs. Rather OVX attenuated Tat/oxycodone interactions. Either Tat or oxycodone increased anxiety-like behavior and their combination increased hypothalamic allopregnanolone. OVX increased basal hypothalamic allopregnanolone and obviated Tat or oxycodone-mediated fluctuations. Together, these data provide further evidence for Tat-mediated dysregulation of the HPA axis and reveal the importance of HPG axis regulation in females. HPA/HPG disruption may contribute vulnerability to affective and substance use disorders.
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Panda S, Behera S, Alam MF, Syed GH. Endoplasmic reticulum & mitochondrial calcium homeostasis: The interplay with viruses. Mitochondrion 2021; 58:227-242. [PMID: 33775873 DOI: 10.1016/j.mito.2021.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 03/08/2021] [Accepted: 03/22/2021] [Indexed: 02/08/2023]
Abstract
Calcium ions (Ca2+) act as secondary messengers in a plethora of cellular processes and play crucial role in cellular organelle function and homeostasis. The average resting concentration of Ca2+ is nearly 100 nM and in certain cells it can reach up to 1 µM. The high range of Ca2+ concentration across the plasma membrane and intracellular Ca2+ stores demands a well-coordinated maintenance of free Ca2+ via influx, efflux, buffering and storage. Endoplasmic Reticulum (ER) and Mitochondria depend on Ca2+ for their function and also serve as major players in intracellular Ca2+ homeostasis. The ER-mitochondria interplay helps in orchestrating cellular calcium homeostasis to avoid any detrimental effect resulting from Ca2+ overload or depletion. Since Ca2+ plays a central role in many biological processes it is an essential component of the virus-host interactions. The large gradient across membranes enable the viruses to easily modulate this buffered environment to meet their needs. Viruses exploit Ca2+ signaling to establish productive infection and evade the host immune defense. In this review we will detail the interplay between the viruses and cellular & ER-mitochondrial calcium signaling and the significance of these events on viral life cycle and disease pathogenesis.
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Affiliation(s)
- Swagatika Panda
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India
| | - Suchismita Behera
- Institute of Life Sciences, Bhubaneswar, Clinical Proteomics Laboratory, Institute of Life Sciences, Bhubaneswar, India
| | - Mohd Faraz Alam
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India
| | - Gulam Hussain Syed
- Institute of Life Sciences, Bhubaneswar, Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneswar, India.
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HIV-1 Vpr mediates the depletion of the cellular repressor CTIP2 to counteract viral gene silencing. Sci Rep 2019; 9:13154. [PMID: 31511615 PMCID: PMC6739472 DOI: 10.1038/s41598-019-48689-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 08/07/2019] [Indexed: 12/15/2022] Open
Abstract
Mammals have evolved many antiviral factors impacting different steps of the viral life cycle. Associated with chromatin-modifying enzymes, the cellular cofactor CTIP2 contributes to HIV-1 gene silencing in latently infected reservoirs that constitute the major block toward an HIV cure. We report, for the first time, that the virus has developed a strategy to overcome this major transcriptional block. Productive HIV-1 infection results in a Vpr-mediated depletion of CTIP2 in microglial cells and CD4+ T cells, two of the major viral reservoirs. Associated to the Cul4A-DDB1-DCAF1 ubiquitin ligase complex, Vpr promotes CTIP2 degradation via the proteasome pathway in the nuclei of target cells and notably at the latent HIV-1 promoter. Importantly, Vpr targets CTIP2 associated with heterochromatin-promoting enzymes dedicated to HIV-1 gene silencing. Thereby, Vpr reactivates HIV-1 expression in a microglial model of HIV-1 latency. Altogether our results suggest that HIV-1 Vpr mediates the depletion of the cellular repressor CTIP2 to counteract viral gene silencing.
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Sims EK, Park G, Mather KJ, Mirmira RG, Liu Z, Gupta SK. Immune reconstitution in ART treated, but not untreated HIV infection, is associated with abnormal beta cell function. PLoS One 2018; 13:e0197080. [PMID: 29795574 PMCID: PMC5967701 DOI: 10.1371/journal.pone.0197080] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/23/2018] [Indexed: 01/05/2023] Open
Abstract
HIV infection has been associated with increased diabetes risk, but prior work has mostly focused on insulin resistance, as opposed to beta cell effects, or included patients on antiretroviral therapies (ART) directly linked to metabolic toxicity. In this analysis, we measured markers of glucose homeostasis and beta cell function, stress, and death in fasting sera from a cross section of HIV+ individuals off ART (n = 43), HIV+ individuals on ART (n = 23), and HIV- controls (n = 39). Markers included glucose, HOMA%S, HOMA%B, proinsulin:C-peptide ratio (PI:C ratio), and circulating preproinsulin (INS) DNA. We performed multiple linear regressions with adjustments for age, sex, race, BMI, and smoking status. Compared to HIV- controls, HIV+ participants off ART exhibited similar beta cell function and insulin sensitivity, without increases in markers of beta cell stress or death. Specifically, in HIV+ participants with CD4 counts <350 cells/μL, PI:C ratios were lower than in HIV- controls (p<0.01), suggesting a reduction in intrinsic beta cell stress among this group. By contrast, HIV+ participants on ART had higher fasting glucose (p<0.0001) and lower HOMA%B (p<0.001) compared to HIV- controls. Among the entire HIV+ population, higher HIV RNA correlated with lower fasting glucose (r = -0.57, p<0.001), higher HOMA%B (r = 0.40, p = 0.001), and lower PI:C ratios (r = -0.42, p<0.001), whereas higher CD4 counts correlated with higher PI:C ratios (r = 0.2, p = 0.00499). Our results suggest that HIV seropositivity in the absence of ART does not worsen beta cell function or glucose homeostasis, but immune reconstitution with ART may be associated with worsened beta cell function.
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Affiliation(s)
- Emily K. Sims
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States of America
- * E-mail:
| | - Grace Park
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Kieren J. Mather
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Raghavendra G. Mirmira
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Ziyue Liu
- Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Samir K. Gupta
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States of America
- Division of Infectious Diseases, Indiana University School of Medicine, Indianapolis, IN, United States of America
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The Interactome of the Glucocorticoid Receptor and Its Influence on the Actions of Glucocorticoids in Combatting Inflammatory and Infectious Diseases. Microbiol Mol Biol Rev 2016; 80:495-522. [PMID: 27169854 DOI: 10.1128/mmbr.00064-15] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoids (GCs) have been widely used for decades as a first-line treatment for inflammatory and autoimmune diseases. However, their use is often hampered by the onset of adverse effects or resistance. GCs mediate their effects via binding to glucocorticoid receptor (GR), a transcription factor belonging to the family of nuclear receptors. An important aspect of GR's actions, including its anti-inflammatory capacity, involves its interactions with various proteins, such as transcription factors, cofactors, and modifying enzymes, which codetermine receptor functionality. In this review, we provide a state-of-the-art overview of the protein-protein interactions (PPIs) of GR that positively or negatively affect its anti-inflammatory properties, along with mechanistic insights, if known. Emphasis is placed on the interactions that affect its anti-inflammatory effects in the presence of inflammatory and microbial diseases.
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Hurt DE, Suzuki S, Mayama T, Charmandari E, Kino T. Structural Analysis on the Pathologic Mutant Glucocorticoid Receptor Ligand-Binding Domains. Mol Endocrinol 2016; 30:173-88. [PMID: 26745667 DOI: 10.1210/me.2015-1177] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Glucocorticoid receptor (GR) gene mutations may cause familial or sporadic generalized glucocorticoid resistance syndrome. Most of the missense forms distribute in the ligand-binding domain and impair its ligand-binding activity and formation of the activation function (AF)-2 that binds LXXLL motif-containing coactivators. We performed molecular dynamics simulations to ligand-binding domain of pathologic GR mutants to reveal their structural defects. Several calculated parameters including interaction energy for dexamethasone or the LXXLL peptide indicate that destruction of ligand-binding pocket (LBP) is a primary character. Their LBP defects are driven primarily by loss/reduction of the electrostatic interaction formed by R611 and T739 of the receptor to dexamethasone and a subsequent conformational mismatch, which deacylcortivazol resolves with its large phenylpyrazole moiety and efficiently stimulates transcriptional activity of the mutant receptors with LBP defect. Reduced affinity of the LXXLL peptide to AF-2 is caused mainly by disruption of the electrostatic bonds to the noncore leucine residues of this peptide that determine the peptide's specificity to GR, as well as by reduced noncovalent interaction against core leucines and subsequent exposure of the AF-2 surface to solvent. The results reveal molecular defects of pathologic mutant receptors and provide important insights to the actions of wild-type GR.
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Affiliation(s)
- Darrell E Hurt
- Bioinformatics and Computational Biosciences Branch (D.E.H.), Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852; Program in Reproductive and Adult Endocrinology (S.S., T.M., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Endocrinology, Metabolism and Diabetes (E.C.), First Department of Pediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens 11527, Greece; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha, Qatar
| | - Shigeru Suzuki
- Bioinformatics and Computational Biosciences Branch (D.E.H.), Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852; Program in Reproductive and Adult Endocrinology (S.S., T.M., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Endocrinology, Metabolism and Diabetes (E.C.), First Department of Pediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens 11527, Greece; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha, Qatar
| | - Takafumi Mayama
- Bioinformatics and Computational Biosciences Branch (D.E.H.), Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852; Program in Reproductive and Adult Endocrinology (S.S., T.M., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Endocrinology, Metabolism and Diabetes (E.C.), First Department of Pediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens 11527, Greece; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha, Qatar
| | - Evangelia Charmandari
- Bioinformatics and Computational Biosciences Branch (D.E.H.), Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852; Program in Reproductive and Adult Endocrinology (S.S., T.M., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Endocrinology, Metabolism and Diabetes (E.C.), First Department of Pediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens 11527, Greece; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha, Qatar
| | - Tomoshige Kino
- Bioinformatics and Computational Biosciences Branch (D.E.H.), Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852; Program in Reproductive and Adult Endocrinology (S.S., T.M., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Endocrinology, Metabolism and Diabetes (E.C.), First Department of Pediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens 11527, Greece; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha, Qatar
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10
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Jeng MY, Ali I, Ott M. Manipulation of the host protein acetylation network by human immunodeficiency virus type 1. Crit Rev Biochem Mol Biol 2015; 50:314-25. [PMID: 26329395 DOI: 10.3109/10409238.2015.1061973] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Over the past 15 years, protein acetylation has emerged as a globally important post-translational modification that fine-tunes major cellular processes in many life forms. This dynamic regulatory system is critical both for complex eukaryotic cells and for the viruses that infect them. HIV-1 accesses the host acetylation network by interacting with several key enzymes, thereby promoting infection at multiple steps during the viral life cycle. Inhibitors of host histone deacetylases and bromodomain-containing proteins are now being pursued as therapeutic strategies to enhance current antiretroviral treatment. As more acetylation-targeting compounds are reaching clinical trials, it is time to review the role of reversible protein acetylation in HIV-infected CD4(+) T cells.
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Affiliation(s)
- Mark Y Jeng
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
| | - Ibraheem Ali
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
| | - Melanie Ott
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
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11
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Zahoor MA, Xue G, Sato H, Aida Y. Genome-wide transcriptional profiling reveals that HIV-1 Vpr differentially regulates interferon-stimulated genes in human monocyte-derived dendritic cells. Virus Res 2015; 208:156-63. [PMID: 26116899 DOI: 10.1016/j.virusres.2015.06.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/17/2015] [Accepted: 06/17/2015] [Indexed: 12/21/2022]
Abstract
Dendritic cells (DCs) are potent antigen-presenting cells (APCs) that directly link the innate and adaptive immune responses. HIV-1 infection of DCs leads to a diverse array of changes in gene expression and play a major role in dissemination of the virus into T-cells. Although HIV-1 Vpr is a pleiotropic protein involved in HIV-1 replication and pathogenesis, its exact role in APCs such as DCs remains elusive. In this study, utilizing a microarray-based systemic biology approach, we found that HIV-1 Vpr differentially regulates (fold change >2.0) more than 200 genes, primarily those involved in the immune response and innate immune response including type I interferon signaling pathway. The differential expression profiles of select genes involved in innate immune responses (interferon-stimulated genes [ISGs]), including MX1, MX2, ISG15, ISG20, IFIT1, IFIT2, IFIT3, IFI27, IFI44L, and TNFSF10, were validated by real-time quantitative PCR; the results were consistent with the microarray data. Taken together, our findings are the first to demonstrate that HIV-1 Vpr induces ISGs and activates the type I IFN signaling pathway in human DCs, and provide insights into the role of Vpr in HIV-1 pathogenesis.
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Affiliation(s)
- Muhammad Atif Zahoor
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama 351-0198, Japan; International Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan
| | - Guangai Xue
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama 351-0198, Japan; International Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan; Japanese Foundation of AIDS Prevention, Tokyo, Japan
| | - Hirotaka Sato
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama 351-0198, Japan
| | - Yoko Aida
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama 351-0198, Japan.
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12
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Agarwal N, Balasubramanyam A. Viral mechanisms of adipose dysfunction: lessons from HIV-1 Vpr. Adipocyte 2015; 4:55-9. [PMID: 26167403 DOI: 10.4161/adip.29852] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 07/07/2014] [Accepted: 07/07/2014] [Indexed: 01/02/2023] Open
Abstract
HIV-associated lipodystrophy is a heterogeneous, evolving condition associated with fundamental defects in adipose tissue differentiation, turnover and function. Although many antiretroviral drugs can affect adipose tissues adversely, clinical evidence suggests that factors associated with the virus per se could play a role. We have focused on the possibility that an HIV accessory protein, viral protein R (Vpr) could dysregulate metabolically critical transcription factors to cause the adipose dysfunction. In a recent study published in Science Translational Medicine, we utilized 2 animal models to show that Vpr, produced in tissues that sequester HIV after antiretroviral therapy, can act in a paracrine or endocrine fashion to disrupt adipocyte differentiation and function by inhibiting PPARγ target gene expression and activating glucocorticoid target gene expression. The phenotypic consequences included many features typical of the human syndrome, including accelerated lipolysis, increased macrophage infiltration in adipose tissue, diminished size of white adipose depots and hepatic steatosis. In this commentary, we summarize the background, results, and implications of these studies, and raise important questions for future investigation. More broadly, these studies suggest that chronic viral infections may be a causative factor in the pathogenesis of some forms of lipid metabolic disease, insulin resistance, and diabetes.
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13
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Chrousos GP, Zapanti ED. Hypothalamic-pituitary-adrenal axis in HIV infection and disease. Endocrinol Metab Clin North Am 2014; 43:791-806. [PMID: 25169568 DOI: 10.1016/j.ecl.2014.06.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
HIV infection induces hypothalamic-pituitary-adrenal (HPA) axis derangements. Partial glucocorticoid resistance has been observed in a subset of AIDS patients, possibly owing to HIV-induced altered cytokine secretion and action. Because glucocorticoids have immunomodulatory effects, the severity of the HPA axis disorder could play a central role in disease progression. The characteristic phenotype of AIDS patients (visceral obesity, lipodystrophy) may be owing to effects of HIV proteins on the HPA axis, including changes in glucocorticoid and insulin sensitivity of target tissues, as well as altered cytokine production and interaction with the HPA axis, genetic causes, comorbidities, and, possibly, use of antiretroviral agents.
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Affiliation(s)
- George P Chrousos
- First Department of Pediatrics, "Agia Sofia" Children's Hospital, University of Athens, Thivon and Papadiamantopoulou, Athens 11527, Greece
| | - Evangelia D Zapanti
- First Endocrine Department and Diabetes Center, Alexandra Hospital, 80 Vassilisis Sofias Avenue, Athens 11528, Greece.
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14
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Agarwal N, Iyer D, Patel SG, Sekhar RV, Phillips TM, Schubert U, Oplt T, Buras ED, Samson SL, Couturier J, Lewis DE, Rodriguez-Barradas MC, Jahoor F, Kino T, Kopp JB, Balasubramanyam A. HIV-1 Vpr induces adipose dysfunction in vivo through reciprocal effects on PPAR/GR co-regulation. Sci Transl Med 2014; 5:213ra164. [PMID: 24285483 DOI: 10.1126/scitranslmed.3007148] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Viral infections, such as HIV, have been linked to obesity, but mechanistic evidence that they cause adipose dysfunction in vivo is lacking. We investigated a pathogenic role for the HIV-1 accessory protein viral protein R (Vpr), which can coactivate the glucocorticoid receptor (GR) and co-repress peroxisome proliferator-activated receptor γ (PPARγ) in vitro, in HIV-associated adipose dysfunction. Vpr circulated in the blood of most HIV-infected patients tested, including those on antiretroviral therapy (ART) with undetectable viral load. Vpr-mediated mechanisms were dissected in vivo using mouse models expressing the Vpr transgene in adipose tissues and liver (Vpr-Tg) or infused with synthetic Vpr. Both models demonstrated accelerated whole-body lipolysis, hyperglycemia and hypertriglyceridemia, and tissue-specific findings. Fat depots in these mice had diminished mass, macrophage infiltration, and blunted PPARγ target gene expression but increased GR target gene expression. In liver, we observed blunted PPARα target gene expression, steatosis with decreased adenosine monophosphate-activated protein kinase activity, and insulin resistance. Similar to human HIV-infected patients, Vpr circulated in the serum of Vpr-Tg mice. Vpr blocked differentiation in preadipocytes through cell cycle arrest, whereas in mature adipocytes, it increased lipolysis with reciprocally altered association of PPARγ and GR with their target promoters. These results delineate a distinct pathogenic sequence: Vpr, released from HIV-1 in tissue reservoirs after ART, can disrupt PPAR/GR co-regulation and cell cycle control to produce adipose dysfunction and hepatosteatosis. Confirmation of these mechanisms in HIV patients could lead to targeted treatment of the metabolic complications with Vpr inhibitors, GR antagonists, or PPARγ/PPARα agonists.
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Affiliation(s)
- Neeti Agarwal
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, TX 77030, USA
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15
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Liu R, Lin Y, Jia R, Geng Y, Liang C, Tan J, Qiao W. HIV-1 Vpr stimulates NF-κB and AP-1 signaling by activating TAK1. Retrovirology 2014; 11:45. [PMID: 24912525 PMCID: PMC4057933 DOI: 10.1186/1742-4690-11-45] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/20/2014] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The Vpr protein of human immunodeficiency virus type 1 (HIV-1) plays an important role in viral replication. It has been reported that Vpr stimulates the nuclear factor-κB (NF-κB) and activator protein 1 (AP-1) signaling pathways, and thereby regulates viral and host cell gene expression. However, the molecular mechanism behind this function of Vpr is not fully understood. RESULTS Here, we have identified transforming growth factor-β-activated kinase 1 (TAK1) as the important upstream signaling molecule that Vpr associates with in order to activate NF-κB and AP-1 signaling. HIV-1 virion-associated Vpr is able to stimulate phosphorylation of TAK1. This activity of Vpr depends on its association with TAK1, since the S79A Vpr mutant lost interaction with TAK1 and was unable to activate TAK1. This association allows Vpr to promote the interaction of TAB3 with TAK1 and increase the polyubiquitination of TAK1, which renders TAK1 phosphorylation. In further support of the key role of TAK1 in this function of Vpr, knockdown of endogenous TAK1 significantly attenuated the ability of Vpr to activate NF-κB and AP-1 as well as the ability to stimulate HIV-1 LTR promoter. CONCLUSIONS HIV-1 Vpr enhances the phosphorylation and polyubiquitination of TAK1, and as a result, activates NF-κB and AP-1 signaling pathways and stimulates HIV-1 LTR promoter.
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Affiliation(s)
| | | | | | | | | | - Juan Tan
- Key Laboratory of Molecular Microbiology and Biotechnology (Ministry of Education) and Key Laboratory of Microbial Functional Genomics (Tianjin), College of Life Sciences, Nankai University, Tianjin 300071, China.
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16
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Deng A, Chen C, Ishizaka Y, Chen X, Sun B, Yang R. Human immunodeficiency virus type 1 Vpr increases hepatitis C virus RNA replication in cell culture. Virus Res 2014; 184:93-102. [PMID: 24589706 DOI: 10.1016/j.virusres.2014.02.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 02/17/2014] [Accepted: 02/18/2014] [Indexed: 01/02/2023]
Abstract
Human immunodeficiency virus (HIV) coinfection with hepatitis C virus (HCV) is associated with an increased HCV RNA level, as well as a more rapid progression to cirrhosis and end-stage liver disease. However, the mechanism underlying this effect is largely unknown. Here, we investigated the role of HIV-1 Vpr in HCV infection and clearly demonstrated that Vpr increased the replication of both the infectious HCV full-length genome and the subgenomic replicon. We also demonstrated that Vpr increased HCV infection by enhancing RNA replication but not viral entry or translation. Further, we showed that Vpr could partially overcome the anti-HCV effect of PEG-IFN. Our findings not only partially explain the clinical observation that patients coinfected with HIV and HCV have higher levels of HCV RNA and viral load than HCV mono-infected patients but also provide important information for HCV treatment in HIV/HCV coinfected patients.
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Affiliation(s)
- Amei Deng
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Disease, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China
| | - Chao Chen
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Disease, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China
| | - Yukihito Ishizaka
- Department of Intractable Diseases, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Xinwen Chen
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Disease, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China
| | - Binlian Sun
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Disease, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China.
| | - Rongge Yang
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Disease, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China.
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17
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Murakami T, Aida Y. Visualizing Vpr-induced G2 arrest and apoptosis. PLoS One 2014; 9:e86840. [PMID: 24466265 PMCID: PMC3899331 DOI: 10.1371/journal.pone.0086840] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 12/13/2013] [Indexed: 12/05/2022] Open
Abstract
Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1) with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2). The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to characterize the dynamics of the morphological changes that occur during Vpr-induced G2 arrest and apoptosis.
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Affiliation(s)
- Tomoyuki Murakami
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama, Japan
- Laboratory of Viral Infectious Diseases, Department of Medical Genome Sciences, Graduate School of Frontier Science, The University of Tokyo, Wako, Saitama, Japan
| | - Yoko Aida
- Viral Infectious Diseases Unit, RIKEN, Wako, Saitama, Japan
- Laboratory of Viral Infectious Diseases, Department of Medical Genome Sciences, Graduate School of Frontier Science, The University of Tokyo, Wako, Saitama, Japan
- * E-mail:
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18
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Webster Marketon JI, Corry J, Teng MN. The respiratory syncytial virus (RSV) nonstructural proteins mediate RSV suppression of glucocorticoid receptor transactivation. Virology 2014; 449:62-9. [PMID: 24418538 PMCID: PMC3904736 DOI: 10.1016/j.virol.2013.11.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 07/12/2013] [Accepted: 11/06/2013] [Indexed: 12/22/2022]
Abstract
Respiratory syncytial virus (RSV)-induced bronchiolitis in infants is not responsive to glucocorticoids. We have shown that RSV infection impairs glucocorticoid receptor (GR) function. In this study, we have investigated the mechanism by which RSV impairs GR function. We have shown that RSV repression of GR-induced transactivation is not mediated through a soluble autocrine factor. Knock-down of mitochondrial antiviral signaling protein (MAVS), but not retinoic acid-inducible gene 1 (RIG-I) or myeloid differentiation primary response gene 88 (MyD88), impairs GR-mediated gene activation even in mock-infected cells. Over-expression of the RSV nonstructural protein NS1, but not NS2, impairs glucocorticoid-induced transactivation and viruses deleted in NS1 and/or NS2 are unable to repress glucocorticoid-induction of the known GR regulated gene glucocorticoid-inducible leucine zipper (GILZ). These data suggest that the RSV nonstructural proteins mediate RSV repression of GR-induced transactivation and that inhibition of the nonstructural proteins may be a viable target for therapy against RSV-related disease.
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Affiliation(s)
- Jeanette I Webster Marketon
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States; Institute for Behavioral Medicine Research, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States.
| | - Jacqueline Corry
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States.
| | - Michael N Teng
- Joy McCann Culverhouse Airway Disease Research Center, Division of Allergy and Immunology, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, United States
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19
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20
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Abbas W, Herbein G. T-Cell Signaling in HIV-1 Infection. Open Virol J 2013; 7:57-71. [PMID: 23986795 PMCID: PMC3751038 DOI: 10.2174/1874357920130621001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 05/31/2013] [Accepted: 06/04/2013] [Indexed: 12/20/2022] Open
Abstract
HIV exploits the T-cell signaling network to gain access to downstream cellular components, which serves as effective tools to break the cellular barriers. Multiple host factors and their interaction with viral proteins contribute to the complexity of HIV-1 pathogenesis and disease progression. HIV-1 proteins gp120, Nef, Tat and Vpr alter the T-cell signaling pathways by activating multiple transcription factors including NF-ĸB, Sp1 and AP-1. HIV-1 evades the immune system by developing a multi-pronged strategy. Additionally, HIV-1 encoded proteins influence the apoptosis in the host cell favoring or blocking T-cell apoptosis. Thus, T-cell signaling hijacked by viral proteins accounts for both viral persistence and immune suppression during HIV-1 infection. Here, we summarize past and present studies on HIV-1 T-cell signaling with special focus on the possible role of T cells in facilitating viral infection and pathogenesis
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Affiliation(s)
- Wasim Abbas
- Department of Virology, Pathogens & Inflammation Laboratory, UPRES EA4266, SFR FED 4234, University of Franche-Comte, CHRU Besançon, F-25030 Besançon, France
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21
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Casey Klockow L, Sharifi HJ, Wen X, Flagg M, Furuya AKM, Nekorchuk M, de Noronha CMC. The HIV-1 protein Vpr targets the endoribonuclease Dicer for proteasomal degradation to boost macrophage infection. Virology 2013; 444:191-202. [PMID: 23849790 DOI: 10.1016/j.virol.2013.06.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 06/09/2013] [Indexed: 12/13/2022]
Abstract
The HIV-1 protein Vpr enhances macrophage infection, triggers G2 cell cycle arrest, and targets cells for NK-cell killing. Vpr acts through the CRL4(DCAF1) ubiquitin ligase complex to cause G2 arrest and trigger expression of NK ligands. Corresponding ubiquitination targets have not been identified. UNG2 and SMUG1 are the only known substrates for Vpr-directed depletion through CRL4(DCAF1). Here we identify the endoribonuclease Dicer as a target of HIV-1 Vpr-directed proteasomal degradation through CRL4(DCAF1). We show that HIV-1 Vpr inhibits short hairpin RNA function as expected upon reduction of Dicer levels. Dicer inhibits HIV-1 replication in T cells. We demonstrate that Dicer also restricts HIV-1 replication in human monocyte-derived macrophages (MDM) and that reducing Dicer expression in MDMs enhances HIV-1 infection in a Vpr-dependent manner. Our results support a model in which Vpr complexes with human Dicer to boost its interaction with the CRL4(DCAF1) ubiquitin ligase complex and its subsequent degradation.
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Affiliation(s)
- Laurieann Casey Klockow
- Center for Immunology and Microbial Disease, Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
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22
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Bromodomain proteins in HIV infection. Viruses 2013; 5:1571-86. [PMID: 23793227 PMCID: PMC3717722 DOI: 10.3390/v5061571] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/09/2013] [Accepted: 06/13/2013] [Indexed: 02/06/2023] Open
Abstract
Bromodomains are conserved protein modules of ~110 amino acids that bind acetylated lysine residues in histone and non-histone proteins. Bromodomains are present in many chromatin-associated transcriptional regulators and have been linked to diverse aspects of the HIV life cycle, including transcription and integration. Here, we review the role of bromodomain-containing proteins in HIV infection. We begin with a focus on acetylated viral factors, followed by a discussion of structural and biological studies defining the involvement of bromodomain proteins in the HIV life cycle. We end with an overview of promising new studies of bromodomain inhibitory compounds for the treatment of HIV latency.
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Palios J, Kadoglou NPE, Lampropoulos S. The pathophysiology of HIV-/HAART-related metabolic syndrome leading to cardiovascular disorders: the emerging role of adipokines. EXPERIMENTAL DIABETES RESEARCH 2011. [PMID: 22203832 DOI: 10.13039/501100005302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Individuals infected with human immunodeficiency virus (HIV) frequently demonstrate metabolic syndrome (MS) associated with increased incidence of cardiovascular disorders. Characteristics of HIV infection, such as immunodeficiency, viral load, and duration of the disease, in addition to the highly active antiretroviral therapy (HAART) have been suggested to induce MS in these patients. It is well documented that MS involves a number of traditional cardiovascular risk factors, like glucose, lipids, and arterial blood pressure abnormalities, leading to extensive atherogenic arterial wall changes. Nevertheless, the above traditional cardiovascular risk factors merely explain the exacerbated cardiovascular risk in MS. Nowadays, the adipose-tissue derivatives, known as adipokines, have been suggested to contribute to chronic inflammation and the MS-related cardiovascular disease. In view of a novel understanding on how adipokines affect the pathogenesis of HIV/HAART-related MS and cardiovascular complications, this paper focuses on the interaction of the metabolic pathways and the potential cardiovascular consequences. Based on the current literature, we suggest adipokines to have a role in the pathogenesis of the HIV/HAART-related MS. It is crucial to understand the pathophysiology of the HIV/HAART-related MS and apply therapeutic strategies in order to reduce cardiovascular risk in HIV patients.
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Affiliation(s)
- John Palios
- 2nd Department of Cardiology, Attikon University Hospital of Athens, Haidari 12462, Greece
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24
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The pathophysiology of HIV-/HAART-related metabolic syndrome leading to cardiovascular disorders: the emerging role of adipokines. EXPERIMENTAL DIABETES RESEARCH 2011; 2012:103063. [PMID: 22203832 PMCID: PMC3235775 DOI: 10.1155/2012/103063] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 11/01/2011] [Indexed: 01/01/2023]
Abstract
Individuals infected with human immunodeficiency virus (HIV) frequently demonstrate metabolic syndrome (MS) associated with increased incidence of cardiovascular disorders. Characteristics of HIV infection, such as immunodeficiency, viral load, and duration of the disease, in addition to the highly active antiretroviral therapy (HAART) have been suggested to induce MS in these patients. It is well documented that MS involves a number of traditional cardiovascular risk factors, like glucose, lipids, and arterial blood pressure abnormalities, leading to extensive atherogenic arterial wall changes. Nevertheless, the above traditional cardiovascular risk factors merely explain the exacerbated cardiovascular risk in MS. Nowadays, the adipose-tissue derivatives, known as adipokines, have been suggested to contribute to chronic inflammation and the MS-related cardiovascular disease. In view of a novel understanding on how adipokines affect the pathogenesis of HIV/HAART-related MS and cardiovascular complications, this paper focuses on the interaction of the metabolic pathways and the potential cardiovascular consequences. Based on the current literature, we suggest adipokines to have a role in the pathogenesis of the HIV/HAART-related MS. It is crucial to understand the pathophysiology of the HIV/HAART-related MS and apply therapeutic strategies in order to reduce cardiovascular risk in HIV patients.
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25
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Takeda E, Murakami T, Matsuda G, Murakami H, Zako T, Maeda M, Aida Y. Nuclear exportin receptor CAS regulates the NPI-1-mediated nuclear import of HIV-1 Vpr. PLoS One 2011; 6:e27815. [PMID: 22110766 PMCID: PMC3218035 DOI: 10.1371/journal.pone.0027815] [Citation(s) in RCA: 15] [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: 10/26/2011] [Indexed: 11/24/2022] Open
Abstract
Vpr, an accessory protein of human immunodeficiency virus type 1, is a multifunctional protein that plays an important role in viral replication. We have previously shown that the region between residues 17 and 74 of Vpr (VprN17C74) contained a bona fide nuclear localization signal and it is targeted VprN17C74 to the nuclear envelope and then imported into the nucleus by importin α (Impα) alone. The interaction between Impα and Vpr is important not only for the nuclear import of Vpr but also for HIV-1 replication in macrophages; however, it was unclear whether full-length Vpr enters the nucleus in a manner similar to VprN17C74. This study investigated the nuclear import of full-length Vpr using the three typical Impα isoforms, Rch1, Qip1 and NPI-1, and revealed that full-length Vpr is selectively imported by NPI-1, but not Rch1 and Qip1, after it makes contact with the perinuclear region in digitonin-permeabilized cells. A binding assay using the three Impα isoforms showed that Vpr bound preferentially to the ninth armadillo repeat (ARM) region (which is also essential for the binding of CAS, the export receptor for Impα) in all three isoforms. Comparison of biochemical binding affinities between Vpr and the Impα isoforms using surface plasmon resonance analysis demonstrated almost identical values for the binding of Vpr to the full-length isoforms and to their C-terminal domains. By contrast, the data showed that, in the presence of CAS, Vpr was released from the Vpr/NPI-1 complex but was not released from Rch1 or Qip1. Finally, the NPI-1–mediated nuclear import of Vpr was greatly reduced in semi-intact CAS knocked-down cells and was recovered by the addition of exogenous CAS. This report is the first to show the requirement for and the regulation of CAS in the functioning of the Vpr-Impα complex.
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Affiliation(s)
- Eri Takeda
- Viral Infectious Diseases Unit, RIKEN, Hirosawa, Wako, Saitama, Japan
| | - Tomoyuki Murakami
- Viral Infectious Diseases Unit, RIKEN, Hirosawa, Wako, Saitama, Japan
- Laboratory of Viral Infectious Diseases, Department of Medical Genome Sciences, Graduate School of Frontier Science, The University of Tokyo, Wako, Saitama, Japan
| | - Go Matsuda
- Viral Infectious Diseases Unit, RIKEN, Hirosawa, Wako, Saitama, Japan
| | - Hironobu Murakami
- Viral Infectious Diseases Unit, RIKEN, Hirosawa, Wako, Saitama, Japan
- Japan Foundation for AIDS Prevention, Chiyoda-ku, Tokyo, Japan
| | - Tamotsu Zako
- Bioengineering Laboratory, RIKEN, Hirosawa, Wako, Saitama, Japan
| | - Mizuo Maeda
- Bioengineering Laboratory, RIKEN, Hirosawa, Wako, Saitama, Japan
| | - Yoko Aida
- Viral Infectious Diseases Unit, RIKEN, Hirosawa, Wako, Saitama, Japan
- Laboratory of Viral Infectious Diseases, Department of Medical Genome Sciences, Graduate School of Frontier Science, The University of Tokyo, Wako, Saitama, Japan
- * E-mail:
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Shimura M, Toyoda Y, Iijima K, Kinomoto M, Tokunaga K, Yoda K, Yanagida M, Sata T, Ishizaka Y. Epigenetic displacement of HP1 from heterochromatin by HIV-1 Vpr causes premature sister chromatid separation. J Cell Biol 2011; 194:721-35. [PMID: 21875947 PMCID: PMC3171121 DOI: 10.1083/jcb.201010118] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 08/03/2011] [Indexed: 11/22/2022] Open
Abstract
Although pericentromeric heterochromatin is essential for chromosome segregation, its role in humans remains controversial. Dissecting the function of HIV-1-encoded Vpr, we unraveled important properties of heterochromatin during chromosome segregation. In Vpr-expressing cells, hRad21, hSgo1, and hMis12, which are crucial for proper chromosome segregation, were displaced from the centromeres of mitotic chromosomes, resulting in premature chromatid separation (PCS). Interestingly, Vpr displaced heterochromatin protein 1-α (HP1-α) and HP1-γ from chromatin. RNA interference (RNAi) experiments revealed that down-regulation of HP1-α and/or HP1-γ induced PCS, concomitant with the displacement of hRad21. Notably, Vpr stimulated the acetylation of histone H3, whereas p300 RNAi attenuated the Vpr-induced displacement of HP1-α and PCS. Furthermore, Vpr bound to p300 that was present in insoluble regions of the nucleus, suggesting that Vpr aberrantly recruits the histone acetyltransferase activity of p300 to chromatin, displaces HP1-α, and causes chromatid cohesion defects. Our study reveals for the first time centromere cohesion impairment resulting from epigenetic disruption of higher-order structures of heterochromatin by a viral pathogen.
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Affiliation(s)
- Mari Shimura
- Department of Intractable Diseases, Research Institute, National Center for Global Health and Medicine, Shinjuku, Tokyo 162-8655, Japan.
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27
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Sarmady M, Dampier W, Tozeren A. HIV protein sequence hotspots for crosstalk with host hub proteins. PLoS One 2011; 6:e23293. [PMID: 21858059 PMCID: PMC3156123 DOI: 10.1371/journal.pone.0023293] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 07/12/2011] [Indexed: 11/18/2022] Open
Abstract
HIV proteins target host hub proteins for transient binding interactions. The presence of viral proteins in the infected cell results in out-competition of host proteins in their interaction with hub proteins, drastically affecting cell physiology. Functional genomics and interactome datasets can be used to quantify the sequence hotspots on the HIV proteome mediating interactions with host hub proteins. In this study, we used the HIV and human interactome databases to identify HIV targeted host hub proteins and their host binding partners (H2). We developed a high throughput computational procedure utilizing motif discovery algorithms on sets of protein sequences, including sequences of HIV and H2 proteins. We identified as HIV sequence hotspots those linear motifs that are highly conserved on HIV sequences and at the same time have a statistically enriched presence on the sequences of H2 proteins. The HIV protein motifs discovered in this study are expressed by subsets of H2 host proteins potentially outcompeted by HIV proteins. A large subset of these motifs is involved in cleavage, nuclear localization, phosphorylation, and transcription factor binding events. Many such motifs are clustered on an HIV sequence in the form of hotspots. The sequential positions of these hotspots are consistent with the curated literature on phenotype altering residue mutations, as well as with existing binding site data. The hotspot map produced in this study is the first global portrayal of HIV motifs involved in altering the host protein network at highly connected hub nodes.
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MESH Headings
- Amino Acid Motifs/genetics
- Amino Acid Sequence
- Binding Sites/genetics
- CREB-Binding Protein/metabolism
- Calcium-Calmodulin-Dependent Protein Kinases/metabolism
- Calmodulin/metabolism
- Casein Kinase II/metabolism
- Databases, Protein
- Human Immunodeficiency Virus Proteins/chemistry
- Human Immunodeficiency Virus Proteins/genetics
- Human Immunodeficiency Virus Proteins/metabolism
- Humans
- Hydrophobic and Hydrophilic Interactions
- Mitogen-Activated Protein Kinase 1/metabolism
- Models, Molecular
- Protein Binding
- Protein Interaction Mapping/methods
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Proteins/genetics
- Proteins/metabolism
- env Gene Products, Human Immunodeficiency Virus/chemistry
- env Gene Products, Human Immunodeficiency Virus/genetics
- env Gene Products, Human Immunodeficiency Virus/metabolism
- gag Gene Products, Human Immunodeficiency Virus/chemistry
- gag Gene Products, Human Immunodeficiency Virus/genetics
- gag Gene Products, Human Immunodeficiency Virus/metabolism
- nef Gene Products, Human Immunodeficiency Virus/chemistry
- nef Gene Products, Human Immunodeficiency Virus/genetics
- nef Gene Products, Human Immunodeficiency Virus/metabolism
- rev Gene Products, Human Immunodeficiency Virus/chemistry
- rev Gene Products, Human Immunodeficiency Virus/genetics
- rev Gene Products, Human Immunodeficiency Virus/metabolism
- tat Gene Products, Human Immunodeficiency Virus/chemistry
- tat Gene Products, Human Immunodeficiency Virus/genetics
- tat Gene Products, Human Immunodeficiency Virus/metabolism
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Affiliation(s)
- Mahdi Sarmady
- Center for Integrated Bioinformatics, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - William Dampier
- Center for Integrated Bioinformatics, Drexel University, Philadelphia, Pennsylvania, United States of America
| | - Aydin Tozeren
- Center for Integrated Bioinformatics, Drexel University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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28
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Zhao RY, Li G, Bukrinsky MI. Vpr-host interactions during HIV-1 viral life cycle. J Neuroimmune Pharmacol 2011; 6:216-29. [PMID: 21318276 PMCID: PMC5482210 DOI: 10.1007/s11481-011-9261-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Accepted: 01/23/2011] [Indexed: 12/21/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) is a multifunctional viral protein that plays important role at multiple stages of the HIV-1 viral life cycle. Although the molecular mechanisms underlying these activities are subject of ongoing investigations, overall, these activities have been linked to promotion of viral replication and impairment of anti-HIV immunity. Importantly, functional defects of Vpr have been correlated with slow disease progression of HIV-infected patients. Vpr is required for efficient viral replication in non-dividing cells such as macrophages, and it promotes, to some extent, viral replication in proliferating CD4+ T cells. The specific activities of Vpr include modulation of fidelity of viral reverse transcription, nuclear import of the HIV-1 pre-integration complex, transactivation of the HIV-1 LTR promoter, induction of cell cycle G2 arrest and cell death via apoptosis. In this review, we focus on description of the cellular proteins that specifically interact with Vpr and discuss their significance with regard to the known Vpr activities at each step of the viral life cycle in proliferating and non-proliferating cells.
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Affiliation(s)
- Richard Y Zhao
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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29
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Taneichi D, Iijima K, Doi A, Koyama T, Minemoto Y, Tokunaga K, Shimura M, Kano S, Ishizaka Y. Identification of SNF2h, a chromatin-remodeling factor, as a novel binding protein of Vpr of human immunodeficiency virus type 1. J Neuroimmune Pharmacol 2011; 6:177-87. [PMID: 21519849 DOI: 10.1007/s11481-011-9276-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 03/16/2011] [Indexed: 12/24/2022]
Abstract
Vpr, an accessory gene of human immunodeficiency virus type 1, encodes a virion-associated nuclear protein that plays an important role in the primary viral infection of resting macrophages. It has a variety of biological functions, including roles in a cell cycle abnormality at G(2)/M phase, apoptosis, nuclear transfer of preintegration complex, and DNA double-strand breaks (DSBs), some of which depend on its association with the chromatin of the host cells. Given that DSB signals are postulated to be a positive factor in the viral infection, understanding the mode of chromatin recruitment of Vpr is important. Here, we identified SNF2h, a chromatin-remodeling factor, as a novel binding partner of Vpr involved in its chromatin recruitment. When endogenous SNF2h protein was extensively downregulated by SNF2h small interfering RNA (siRNA), the amount of Vpr loaded on chromatin decreased to about 30% of the control level. Biochemical analysis using a mutant Vpr suggested that Vpr binds SNF2h via HFRIG (amino acids 71-75 depicted by single letters) and the Vpr mutant lacking this motif lost the activity to induce DSB-dependent signals. Consistently, Vpr-induced DSBs were attenuated by extensive downregulaion of endogenous SNF2h. Based on these data, we discuss the role of DSB and DSB signals in the viral infection.
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Affiliation(s)
- Daiki Taneichi
- Department of Intractable Diseases, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku, Tokyo 162-8655, Japan
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30
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Ong EBB, Watanabe N, Saito A, Futamura Y, Abd El Galil KH, Koito A, Najimudin N, Osada H. Vipirinin, a coumarin-based HIV-1 Vpr inhibitor, interacts with a hydrophobic region of VPR. J Biol Chem 2011; 286:14049-56. [PMID: 21357691 PMCID: PMC3077605 DOI: 10.1074/jbc.m110.185397] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 02/27/2011] [Indexed: 11/06/2022] Open
Abstract
The human immunodeficiency virus 1 (HIV-1) viral protein R (Vpr) is an accessory protein that has been shown to have multiple roles in HIV-1 pathogenesis. By screening chemical libraries in the RIKEN Natural Products Depository, we identified a 3-phenyl coumarin-based compound that inhibited the cell cycle arrest activity of Vpr in yeast and Vpr-dependent viral infection of human macrophages. We determined its minimal pharmacophore through a structure-activity relationship study and produced more potent derivatives. We detected direct binding, and by assaying a panel of Vpr mutants, we found the hydrophobic region about residues Glu-25 and Gln-65 to be potentially involved in the binding of the inhibitor. Our findings exposed a targeting site on Vpr and delineated a convenient approach to explore other targeting sites on the protein using small molecule inhibitors as bioprobes.
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Affiliation(s)
- Eugene Boon Beng Ong
- From the Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- the School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia, and
| | - Nobumoto Watanabe
- From the Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- the School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia, and
| | - Akiko Saito
- From the Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Yushi Futamura
- From the Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Khaled Hussein Abd El Galil
- the Department of Retrovirology and Self-Defense, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Atsushi Koito
- the Department of Retrovirology and Self-Defense, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Nazalan Najimudin
- the School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia, and
| | - Hiroyuki Osada
- From the Chemical Biology Core Facility, Chemical Biology Department, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- the School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia, and
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31
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Wu XL, Zhang WG, Shi XM, An P, Sun WS, Qiao CL, Wang Z. Effect of artemisinin combined with glucocorticoid on the expressions of glucocorticoid receptor α mRNA, glucocorticoid receptor β mRNA and P300/CBP protein in lupus nephritis mice. Chin J Integr Med 2011; 17:277-82. [PMID: 21509671 DOI: 10.1007/s11655-011-0693-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To investigate the therapeutic effects and mechanisms of using artemisinin (Art) combined with glucocorticoid (GC) to treat lupus nephritis (LN) mice. METHODS Forty hybrid female mice were randomly and equally divided into four groups with the method of random number table: control group, model group, prednisone group administrated with 6.45 mg/(kg·d) prednisone suspension, and Art+prednisone group administrated with 150 mg/(kg·d) Art suspension and 3.225 mg/(kg·d) prednisone suspension. A mice model of LN was established by injection with living lymph cell suspension. The changes of urine protein/24h, the expressions of GC receptor α (GRα) mRNA, GC receptor β (GRβ) mRNA in peripheral blood mononuclear cells (PBMCs), and transcriptional coactivator P300/CBP protein in renal tissue were measured. RESULTS Compared with the model group, the treatment groups had significant decrease in urine protein/24 h, and renal pathological lesion (P<0.01). In the same groups, the expression of transcriptional coactivator P300/CBP protein in renal tissue and GRα mRNA were significantly increased, and GRβ mRNA expression was significantly decreased (P<0.01). And the Art+prednisone group has a better therapeutic effect than the prednisone group (P<0.01). CONCLUSIONS Art has therapeutic sensitization effects on GC in the LN mice. The underlying mechanism could be correlated with the effect of Art on the increase of the expressions of GRα mRNA and transcriptional coactivator P300 300/CBP protein in renal tissue and on the decrease of the expression of GRβ mRNA in PBMC.
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Affiliation(s)
- Xi-Li Wu
- Department of Integrated Chinese Traditional and Western Medicine, Shaanxi Province Key Traditional Chinese Medicine, Department of Nephrology, Second Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an (710004), China.
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32
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Kogan M, Rappaport J. HIV-1 accessory protein Vpr: relevance in the pathogenesis of HIV and potential for therapeutic intervention. Retrovirology 2011; 8:25. [PMID: 21489275 PMCID: PMC3090340 DOI: 10.1186/1742-4690-8-25] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 04/13/2011] [Indexed: 01/11/2023] Open
Abstract
The HIV protein, Vpr, is a multifunctional accessory protein critical for efficient viral infection of target CD4+ T cells and macrophages. Vpr is incorporated into virions and functions to transport the preintegration complex into the nucleus where the process of viral integration into the host genome is completed. This action is particularly important in macrophages, which as a result of their terminal differentiation and non-proliferative status, would be otherwise more refractory to HIV infection. Vpr has several other critical functions including activation of HIV-1 LTR transcription, cell-cycle arrest due to DCAF-1 binding, and both direct and indirect contributions to T-cell dysfunction. The interactions of Vpr with molecular pathways in the context of macrophages, on the other hand, support accumulation of a persistent reservoir of HIV infection in cells of the myeloid lineage. The role of Vpr in the virus life cycle, as well as its effects on immune cells, appears to play an important role in the immune pathogenesis of AIDS and the development of HIV induced end-organ disease. In view of the pivotal functions of Vpr in virus infection, replication, and persistence of infection, this protein represents an attractive target for therapeutic intervention.
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Affiliation(s)
- Michael Kogan
- Department of Neuroscience, Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, 3500 North Broad Street, Philadelphia, PA 19140, USA
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33
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Abstract
PURPOSE OF REVIEW To review the current scientific literature and recent clinical trials on HIV protease inhibitors and their potential role in the pathogenesis of lipodystrophy and metabolic disorders. RECENT FINDINGS HIV protease inhibitor treatment may affect the normal stimulatory effect of insulin on glucose and fat storage. Further, chronic inflammation from HIV infection and protease inhibitor treatment trigger cellular homeostatic stress responses with adverse effects on intermediary metabolism. The physiologic outcome is such that total adipocyte storage capacity is decreased, and the remaining adipocytes resist further fat storage. This process leads to a pathologic cycle of lipodystrophy and lipotoxicity, a proatherogenic lipid profile, and a clinical phenotype of increased central body fat distribution similar to the metabolic syndrome. SUMMARY Protease inhibitors are a key component of antiretroviral therapy and have dramatically improved the life expectancy of HIV-infected individuals. However, they are also associated with abnormalities in glucose/lipid metabolism and body fat distribution. Further studies are needed to better define the pathogenesis of protease inhibitor-associated metabolic and body fat changes and their potential treatment.
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Affiliation(s)
| | - Andrew Bremer
- Department of Pediatrics, University of California, Davis, CA
| | - Lars Berglund
- Departments of Medicine University of California, Davis, CA
- VA Northern California Health Care System, Sacramento, CA
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34
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The HIV-1/HAART associated metabolic syndrome – Novel adipokines, molecular associations and therapeutic implications. J Infect 2010; 61:101-13. [DOI: 10.1016/j.jinf.2010.06.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 05/18/2010] [Accepted: 06/07/2010] [Indexed: 10/19/2022]
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35
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Hapgood JP, Tomasicchio M. Modulation of HIV-1 virulence via the host glucocorticoid receptor: towards further understanding the molecular mechanisms of HIV-1 pathogenesis. Arch Virol 2010; 155:1009-19. [PMID: 20446002 DOI: 10.1007/s00705-010-0678-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 03/26/2010] [Indexed: 10/19/2022]
Abstract
The glucocorticoid receptor (GR) is a steroid receptor that regulates diverse functions, which include the immune response. In humans, the GR acts via binding to cortisol, resulting in the transcriptional modulation of key host genes. Several lines of evidence suggest that the host GR could be a key protein exploited by HIV at multiple levels to ensure its pathogenic success. Endogenous and therapeutic glucocorticoids play important roles in patients with HIV due to their well-established effects on immune function. AIDS patients develop glucocorticoid hypersensitivity, consistent with a mechanism involving an HIV-1-induced increase in expression or activity of the GR. Both the HIV-1 accessory protein Vpr and the host GR affect transcription of viral proteins from the long terminal repeat (LTR) region of the HIV-1 promoter. In addition, Vpr modulates host GR function to affect transcription of host genes, most likely via direct interaction with the GR. Vpr appears to regulate GR function by acting as a co-activator for the GR. Since both the GR and Vpr are involved in apoptosis in T cells and dendritic cells, crosstalk between these proteins may also regulate apoptosis in these and other cells. Given that cortisol is not the only ligand that activates the GR, other endogenous as well as synthetic GR ligands such as progestins may also modulate HIV pathogenesis, in particular in the cervicovaginal environment. Investigating the molecular determinants, ligand-selectivity and role in HIV pathogenesis of the GR-Vpr interaction may lead to new strategies for development of anti-HIV drugs.
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Affiliation(s)
- Janet Patricia Hapgood
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa.
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36
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Abstract
Like most viral regulatory proteins, HIV-1 Vpr and homologous proteins from primate lentiviruses are small and multifunctional. They are associated with a plethora of effects and functions, including induction of cell cycle arrest in the G(2) phase, induction of apoptosis, transactivation, enhancement of the fidelity of reverse transcription, and nuclear import of viral DNA in macrophages and other nondividing cells. This review focuses on the cellular proteins that have been reported to interact with Vpr and their significance with respect to the known functions and effects of Vpr on cells and on viral replication.
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Affiliation(s)
- Vicente Planelles
- Division of Cell Biology and Immunology, Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East #2100-Room 2520, Salt Lake City, Utah 84112, USA.
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37
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Casey L, Wen X, de Noronha CMC. The functions of the HIV1 protein Vpr and its action through the DCAF1.DDB1.Cullin4 ubiquitin ligase. Cytokine 2010; 51:1-9. [PMID: 20347598 DOI: 10.1016/j.cyto.2010.02.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2009] [Revised: 01/30/2010] [Accepted: 02/24/2010] [Indexed: 01/21/2023]
Abstract
Among the proteins encoded by human and simian immunodeficiency viruses (HIV and SIV) at least three, Vif, Vpu and Vpr, subvert cellular ubiquitin ligases to block the action of anti-viral defenses. This review focuses on Vpr and its HIV2/SIV counterparts, Vpx and Vpr, which all engage the DDB1.Cullin4 ubiquitin ligase complex through the DCAF1 adaptor protein. Here, we discuss the multiple functions that have been linked to Vpr expression and summarize the current knowledge on the role of the ubiquitin ligase complex in carrying out a subset of these activities.
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Affiliation(s)
- Laurieann Casey
- Center for Immunology and Microbial Disease, Albany Medical College, 43 New Scotland Avenue, Albany, NY 12208, USA
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38
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Tazi J, Bakkour N, Marchand V, Ayadi L, Aboufirassi A, Branlant C. Alternative splicing: regulation of HIV-1 multiplication as a target for therapeutic action. FEBS J 2010; 277:867-76. [DOI: 10.1111/j.1742-4658.2009.07522.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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39
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Chrousos GP, Kino T. Glucocorticoid signaling in the cell. Expanding clinical implications to complex human behavioral and somatic disorders. Ann N Y Acad Sci 2009; 1179:153-66. [PMID: 19906238 DOI: 10.1111/j.1749-6632.2009.04988.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Glucocorticoids contribute to the maintenance of basal and stress-related homeostasis in all higher organisms, and influence a large proportion of the expressed human genome, and their effects spare almost no organs or tissues. Glucocorticoids regulate many functions of the central nervous system, such as arousal, cognition, mood, sleep, the activity and direction of intermediary metabolism, the maintenance of a proper cardiovascular tone, the activity and quality of the immune and inflammatory reaction, including the manifestations of the sickness syndrome, and growth and reproduction. The numerous actions of glucocorticoids are mediated by a set of at least 16 glucocorticoid receptor (GR) isoforms forming homo- or hetero-dimers. The GRs consist of multifunctional domain proteins operating as ligand-dependent transcription factors that interact with many other cell signaling systems, including large and small G proteins. The presence of multiple GR monomers and homo- or hetero-dimers expressed in a cell-specific fashion at different quantities with quantitatively and qualitatively different transcriptional activities suggest that the glucocorticoid signaling system is highly stochastic. Glucocorticoids are heavily involved in human pathophysiology and influence life expectancy. Common behavioral and/or somatic complex disorders, such as anxiety, depression, insomnia, chronic pain and fatigue syndromes, obesity, the metabolic syndrome, essential hypertension, diabetes type 2, atherosclerosis with its cardiovascular sequelae, and osteoporosis, as well as autoimmune inflammatory and allergic disorders, all appear to have a glucocorticoid-regulated component.
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Affiliation(s)
- George P Chrousos
- First Department of Pediatrics, Athens University Medical School, Athens, Greece.
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40
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Easley R, Van Duyne R, Coley W, Guendel I, Dadgar S, Kehn-Hall K, Kashanchi F. Chromatin dynamics associated with HIV-1 Tat-activated transcription. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2009; 1799:275-85. [PMID: 19716452 DOI: 10.1016/j.bbagrm.2009.08.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Revised: 08/14/2009] [Accepted: 08/20/2009] [Indexed: 02/07/2023]
Abstract
Chromatin remodeling is an essential event for HIV-1 transcription. Over the last two decades this field of research has come to the forefront, as silencing of the HIV-1 provirus through chromatin modifications has been linked to latency. Here, we focus on chromatin remodeling, especially in relation to the transactivator Tat, and review the most important and newly emerging studies that investigate remodeling mechanisms. We begin by discussing covalent modifications that can alter chromatin structure including acetylation, deacetylation, and methylation, as well as topics addressing the interplay between chromatin remodeling and splicing. Next, we focus on complexes that use the energy of ATP to remove or secure nucleosomes and can additionally act to control HIV-1 transcription. Finally, we cover recent literature on viral microRNAs which have been shown to alter chromatin structure by inducing methylation or even by remodeling nucleosomes.
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Affiliation(s)
- Rebecca Easley
- The George Washington University Medical Center, Department of Microbiology, Immunology, and Tropical Medicine, Washington, DC 20037, USA
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41
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Nonaka M, Hashimoto Y, Takeshima SN, Aida Y. The human immunodeficiency virus type 1 Vpr protein and its carboxy-terminally truncated form induce apoptosis in tumor cells. Cancer Cell Int 2009; 9:20. [PMID: 19674438 PMCID: PMC2735735 DOI: 10.1186/1475-2867-9-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Accepted: 08/12/2009] [Indexed: 01/19/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) accessory protein Vpr induces apoptosis after cell cycle arrest at the G2 phase in primate cells. We have reported previously that C81, a carboxy-terminally truncated form of Vpr, interferes with cell proliferation and results in apoptosis without G2 arrest. Here, we investigated whether this property of Vpr and C81 could be exploited for use as a potential anticancer agent. First, we demonstrated that C81 induced G1 arrest and apoptosis in all tumor cells tested. In contrast, Vpr resulted in G2 arrest and apoptosis in HeLa and 293 T cells. Vpr also suppressed the damaged-DNA-specific binding protein 1 (DDB1) in HepG2 cells, thereby inducing apoptosis without G2 arrest. G2 arrest was restored when DDB1 was overexpressed in cells that also expressed Vpr. Surprisingly, C81 induced G2 arrest when DDB1 was overexpressed in HepG2 cells, but not in HeLa or 293 T cells. Thus, the induction of Vpr- and C81-mediated cell cycle arrest appears to depend on the cell type, whereas apoptosis was observed in all tumor cells tested. Overall, Vpr and C81 have potential as novel therapeutic agents for treatment of cancer.
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Affiliation(s)
- Mizuho Nonaka
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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42
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Zhou Y, Frey TK, Yang JJ. Viral calciomics: interplays between Ca2+ and virus. Cell Calcium 2009; 46:1-17. [PMID: 19535138 PMCID: PMC3449087 DOI: 10.1016/j.ceca.2009.05.005] [Citation(s) in RCA: 206] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Revised: 05/15/2009] [Accepted: 05/18/2009] [Indexed: 12/23/2022]
Abstract
Ca2+ is one of the most universal and versatile signaling molecules and is involved in almost every aspect of cellular processes. Viruses are adept at utilizing the universal Ca2+ signal to create a tailored cellular environment that meets their own demands. This review summarizes most of the known mechanisms by which viruses perturb Ca2+ homeostasis and utilize Ca2+ and cellular Ca2+-binding proteins to their benefit in their replication cycles. Ca2+ plays important roles in virion structure formation, virus entry, viral gene expression, posttranslational processing of viral proteins and virion maturation and release. As part of the review, we introduce an algorithm to identify linear “EF-hand” Ca2+-binding motifs which resulted in the prediction of a total of 93 previously unrecognized Ca2+-binding motifs in virus proteins. Many of these proteins are nonstructural proteins, a class of proteins among which Ca2+ interactions had not been formerly appreciated. The presence of linear Ca2+-binding motifs in viral proteins enlarges the spectrum of Ca2+–virus interplay and expands the total scenario of viral calciomics.
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Affiliation(s)
- Yubin Zhou
- Department of Chemistry, Georgia State University, 50 Decatur St., Atlanta, GA 30303 USA
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43
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Romani B, Engelbrecht S. Human immunodeficiency virus type 1 Vpr: functions and molecular interactions. J Gen Virol 2009; 90:1795-1805. [PMID: 19458171 DOI: 10.1099/vir.0.011726-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) is an accessory protein that interacts with a number of cellular and viral proteins. The functions of many of these interactions in the pathogenesis of HIV-1 have been identified. Deletion of the vpr gene reduces the virulence of HIV-1 dramatically, indicating the importance of this protein for the virus. This review describes the current findings on several established functions of HIV-1 Vpr and some possible roles proposed for this protein. Because Vpr exploits cellular proteins and pathways to influence the biology of HIV-1, understanding the functions of Vpr usually involves the study of cellular pathways. Several functions of Vpr are attributed to the virion-incorporated protein, but some of them are attributed to the expression of Vpr in HIV-1-infected cells. The structure of Vpr may be key to understanding the variety of its interactions. Due to the critical role of Vpr in HIV-1 pathogenicity, study of the interactions between Vpr and cellular proteins may help us to understand the mechanism(s) of HIV-1 pathogenicity.
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Affiliation(s)
- Bizhan Romani
- Department of Pathology, Division of Medical Virology, University of Stellenbosch, Tygerberg 7505, South Africa
| | - Susan Engelbrecht
- National Health Laboratory Services, Tygerberg 7505, South Africa.,Department of Pathology, Division of Medical Virology, University of Stellenbosch, Tygerberg 7505, South Africa
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44
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Nader N, Chrousos GP, Kino T. Circadian rhythm transcription factor CLOCK regulates the transcriptional activity of the glucocorticoid receptor by acetylating its hinge region lysine cluster: potential physiological implications. FASEB J 2009; 23:1572-83. [PMID: 19141540 PMCID: PMC2669420 DOI: 10.1096/fj.08-117697] [Citation(s) in RCA: 232] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 12/11/2008] [Indexed: 01/15/2023]
Abstract
Glucocorticoids, end products of the hypothalamic-pituitary-adrenal axis, influence functions of virtually all organs and tissues through the glucocorticoid receptor (GR). Circulating levels of glucocorticoids fluctuate naturally in a circadian fashion and regulate the transcriptional activity of GR in target tissues. The basic helix-loop-helix protein CLOCK, a histone acetyltransferase (HAT), and its heterodimer partner BMAL1 are self-oscillating transcription factors that generate circadian rhythms in both the central nervous system and periphery. We found that CLOCK/BMAL1 repressed GR-induced transcriptional activity in a HAT-activity- dependent fashion. In serum-shock-synchronized cells, transactivational activity of GR, accessed by mRNA expression of an endogenous-responsive gene, fluctuated spontaneously in a circadian fashion in reverse phase with CLOCK/BMAL1 mRNA expression. CLOCK and GR interacted with each other physically, and CLOCK suppressed binding of GR to its DNA recognition sequences by acetylating multiple lysine residues located in its hinge region. These findings indicate that CLOCK/BMAL1 functions as a reverse-phase negative regulator of glucocorticoid action in target tissues, possibly by antagonizing biological actions of diurnally fluctuating circulating glucocorticoids. Further, these results suggest that a peripheral target tissue circadian rhythm indirectly influences the functions of every organ and tissue inside the body through modulation of the ubiquitous and diverse actions of glucocorticoids.
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Affiliation(s)
- Nancy Nader
- Section on Pediatric Endocrinology, Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1109, USA
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45
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Romani B, Glashoff R, Engelbrecht S. Molecular and phylogenetic analysis of HIV type 1 vpr sequences of South African strains. AIDS Res Hum Retroviruses 2009; 25:357-62. [PMID: 19271970 DOI: 10.1089/aid.2008.0251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HIV-1 subtype C is the prevalent subtype in South Africa, with non-C subtypes being sporadically detected. The accessory genes of subtype C have not been well studied in South Africa. In this study the HIV-1 vpr region of 58 strains was amplified, sequenced, and subtyped. Phylogenetic analysis characterized 54 strains as HIV-1 subtype C and 4 strains as HIV-1 subtype B. The amino acid sequence of the protein was also investigated. The overall amino acid sequence of Vpr was conserved as well as the motifs FPRPWL (34-39: IH1) and TYGDTW (49-54: IH2). The C-terminal was more variable. The importance of these motifs and variability needs to be addressed.
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Affiliation(s)
- Bizhan Romani
- Department of Pathology, Division of Medical Virology, University of Stellenbosch, Tygerberg 7505, South Africa
| | - Richard Glashoff
- Department of Pathology, Division of Medical Virology, University of Stellenbosch, Tygerberg 7505, South Africa
| | - Susan Engelbrecht
- Department of Pathology, Division of Medical Virology, University of Stellenbosch, Tygerberg 7505, South Africa
- National Health Laboratory Services (NHLS), Tygerberg 7505, South Africa
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46
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Kaul D, Ahlawat A, Gupta SD. HIV-1 genome-encoded hiv1-mir-H1 impairs cellular responses to infection. Mol Cell Biochem 2008; 323:143-8. [PMID: 19082544 DOI: 10.1007/s11010-008-9973-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Accepted: 11/28/2008] [Indexed: 10/21/2022]
Abstract
The recent discovery of HIV-1 genome-encoded novel microRNA (miRNA; designated as hiv1-mir-H1) having ability to target selectively and specifically human cellular AATF gene, prompted us to explore the role of this miRNA in the regulation of genes involved in cellular apoptosis, proliferation and nucleic acid-based immune mechanism governed by miRNAs. Such a study revealed that this miRNA-induced knockdown of AATF gene, within normal human blood mononuclear cells, was responsible for the suppression of genes coding for Bcl-2, c-myc, Par-4 and Dicer. Further, hiv1-mir-H1 had the capacity to downregulate expression of cellular miR149 gene recognized to target Vpr gene encoded by HIV-1. Based upon these findings, we propose an "Epigenomic Pathway" through which hiv1-mir-H1 induced AATF gene knockdown within human mononuclear cells initiates their apoptosis.
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Affiliation(s)
- Deepak Kaul
- Molecular Biology Unit, Department of Experimental Medicine & Biotechnology, PGIMER, Chandigarh, 160 012, India.
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47
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HIV-1 infection and the PPARγ-dependent control of adipose tissue physiology. PPAR Res 2008; 2009:607902. [PMID: 19081837 PMCID: PMC2593159 DOI: 10.1155/2009/607902] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Accepted: 07/23/2008] [Indexed: 01/03/2023] Open
Abstract
PPARγ is a ligand-dependent master transcription factor controlling adipocyte differentiation as well as multiple biological processes taking place in other cells present in adipose tissue depots such as macrophages. Recent research indicates that HIV-1 infection-related events may alter adipose tissue biology through several mechanisms involving PPARγ, ranging from direct effects of HIV-1-encoded proteins on adipocytes to the promotion of a proinflammatory environment that interferes with PPARγ actions. This effect of HIV-1 on adipose tissue cells can occur even in the absence of direct infection of adipocytes, as soluble HIV-1-encoded proteins such as Vpr may enter cells and inhibit PPARγ action. Moreover, repression of PPARγ actions may relieve inhibitory pathways of HIV-1 gene transcription, thus enhancing HIV-1 effects in infected cells. HIV-1 infection-mediated interference of PPARγ-dependent pathways in adipocytes and other cells inside adipose depots such as macrophages is likely to create an altered local environment that, after antiretroviral treatment, leads to lipodystrophy in HIV-1-infected and HAART-treated patients.
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Wiegers K, Schwarck D, Reimer R, Bohn W. Activation of the glucocorticoid receptor releases unstimulated PBMCs from an early block in HIV-1 replication. Virology 2008; 375:73-84. [PMID: 18295813 DOI: 10.1016/j.virol.2008.01.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Revised: 10/19/2007] [Accepted: 01/19/2008] [Indexed: 10/22/2022]
Abstract
Infection of resting peripheral mononuclear blood cells (PBMCs) with HIV-1 is not productive due to a block prior to integration of the provirus into the host genome. Here we show that a unique restriction is determined by the status of the glucocorticoid receptor (GR). Proviral integration increases after addition of a GR ligand. The ligand dependent effect is confined to an early time period after infection and requires GR and the GR binding viral protein Vpr. Endogenous GR and transiently expressed Vpr are localized in the cytoplasm in unstimulated PMCs and comigrate into the nucleus upon ligand addition. Thus, the predominant cytoplasmic localization of GR seems to be a specific obstacle for HIV replication. Accordingly, efficient proviral integration in a cell line with a constitutive cytoplasmic GR requires addition of a GR ligand. The data suggest that steroids can overcome the restriction on HIV provirus formation and thereby increase the reservoir of virus producing cells.
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Affiliation(s)
- Klaus Wiegers
- Heinrich-Pette-Institut für Experimentelle Virologie und Immunologie an der Universität Hamburg, 20251 Hamburg, Germany.
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49
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Proteomic studies reveal coordinated changes in T-cell expression patterns upon infection with human immunodeficiency virus type 1. J Virol 2008; 82:4320-30. [PMID: 18287243 DOI: 10.1128/jvi.01819-07] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We performed an extensive two-dimensional differential in-gel electrophoresis proteomic analysis of the cellular changes in human T cells upon human immunodeficiency virus type 1 (HIV-1) infection. We detected 2,000 protein spots, 15% of which were differentially expressed at peak infection. A total of 93 proteins that changed in relative abundance were identified. Of these, 27 were found to be significantly downregulated and 66 were upregulated at peak HIV infection. Early in infection, only a small group of proteins was changed. A clear and consistent program of metabolic rerouting could be seen, in which glycolysis was downregulated and mitochondrial oxidation enhanced. Proteins that participate in apoptotic signaling were also significantly influenced. Apart from these changes, the virus also strongly influenced levels of proteins involved in intracellular transport. These and other results are discussed in light of previous microarray and proteomic studies regarding the impact of HIV-1 infection on cellular mRNA and protein content.
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50
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Is HIV infection a TNF receptor signalling-driven disease? Trends Immunol 2008; 29:61-7. [DOI: 10.1016/j.it.2007.10.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Revised: 09/20/2007] [Accepted: 10/31/2007] [Indexed: 02/03/2023]
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