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Bulnes-Ramos A, Schott K, Rabinowitz J, Luchsinger C, Bertelli C, Miyagi E, Yu CH, Persaud M, Shepard C, König R, Kim B, Ivanov DN, Strebel K, Diaz-Griffero F. Acetylation of SAMHD1 at lysine 580 is crucial for blocking HIV-1 infection. mBio 2024; 15:e0195824. [PMID: 39162568 PMCID: PMC11389391 DOI: 10.1128/mbio.01958-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 07/10/2024] [Indexed: 08/21/2024] Open
Abstract
In humans, sterile alpha motif (SAM) domain- and histidine-aspartic acid (HD) domain-containing protein 1 (SAMHD1) is a dNTPase enzyme that prevents HIV-1 infection in non-cycling cells, such as differentiated THP-1 cells and human primary macrophages. Although phosphorylation of threonine 592 (T592) in SAMHD1 is recognized as the primary regulator of the ability to prevent HIV-1 infection, the contributions of SAMHD1 acetylation to this ability remain unknown. Mass spectrometry analysis of SAMHD1 proteins derived from cycling and non-cycling THP-1 cells, primary cycling B cells, and primary macrophages revealed that SAMHD1 is preferentially acetylated at lysine residues 354, 494, and 580 (K354, K494, and K580). In non-cycling cells, SAMHD1 is preferentially acetylated at K580, suggesting that this post-translational modification may contribute to the ability of SAMHD1 to block HIV-1 infection. Consistent with this finding, we found that mutations in K580 disrupted the ability of SAMHD1 to block HIV-1 infection without affecting the ability of SAMHD1 to deplete cellular dNTP levels. Gene editing of SAMHD1 in macrophage-like cells revealed that an intact K580 is required for HIV-1 restriction. This finding suggests that K580 acetylation in SAMHD1 is essential for blocking HIV-1 infection. More importantly, we found that a larger proportion of SAMHD1 featuring K580 acetylation could be detected in human primary macrophages when compared to human primary monocytes. In agreement, we found that SAMHD1 is acetylated during the monocyte-to-macrophage differentiation process. This finding agrees with the idea that the blockade of HIV-1 infection in macrophages requires SAMHD1 acetylation.IMPORTANCEThe natural inhibitor of HIV-1, sterile alpha motif (SAM) domain- and histidine-aspartic acid (HD) domain-containing protein 1 (SAMHD1), plays a pivotal role in preventing HIV-1 infection of macrophages and dendritic cells, which are vital components of the immune system. This study unveils that SAMHD1 undergoes post-translational modifications, specifically acetylation at lysines 354, 494, and 580. Our research underscores the significance of these modifications, demonstrating that acetylation at residue K580 is indispensable for SAMHD1's efficacy in blocking HIV-1 infection. Notably, K580 is found in a critical regulatory domain of SAMHD1, highlighting acetylation as a novel layer of SAMHD1 regulation for HIV-1 restriction in humans. A comprehensive understanding of the regulation mechanisms governing this anti-HIV-1 protein is crucial for leveraging nature's defense mechanisms against HIV-1 and could pave the way for innovative therapeutic strategies.
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Affiliation(s)
- Angel Bulnes-Ramos
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Kerstin Schott
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, Langen, Germany
| | - Jesse Rabinowitz
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Charlotte Luchsinger
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Cinzia Bertelli
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Eri Miyagi
- Viral Biochemistry Section NIAID, NIH, Bethesda, Maryland, USA
| | - Corey H Yu
- Department of Biochemistry, UTHSA, San Antonio, Texas, USA
| | - Mirjana Persaud
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Caitlin Shepard
- Department of Pediatrics, Center for ViroScience and Cure, School of Medicine, Emory University, Atlanta, Georgia, USA
- Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, Langen, Germany
| | - Baek Kim
- Department of Pediatrics, Center for ViroScience and Cure, School of Medicine, Emory University, Atlanta, Georgia, USA
- Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | | | - Klaus Strebel
- Viral Biochemistry Section NIAID, NIH, Bethesda, Maryland, USA
| | - Felipe Diaz-Griffero
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
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Lo SY, Lai MJ, Yang CH, Li HC. Unveiling the Connection: Viral Infections and Genes in dNTP Metabolism. Viruses 2024; 16:1412. [PMID: 39339888 PMCID: PMC11437409 DOI: 10.3390/v16091412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2024] [Revised: 08/31/2024] [Accepted: 09/01/2024] [Indexed: 09/30/2024] Open
Abstract
Deoxynucleoside triphosphates (dNTPs) are crucial for the replication and maintenance of genomic information within cells. The balance of the dNTP pool involves several cellular enzymes, including dihydrofolate reductase (DHFR), ribonucleotide reductase (RNR), and SAM and HD domain-containing protein 1 (SAMHD1), among others. DHFR is vital for the de novo synthesis of purines and deoxythymidine monophosphate, which are necessary for DNA synthesis. SAMHD1, a ubiquitously expressed deoxynucleotide triphosphohydrolase, converts dNTPs into deoxynucleosides and inorganic triphosphates. This process counteracts the de novo dNTP synthesis primarily carried out by RNR and cellular deoxynucleoside kinases, which are most active during the S phase of the cell cycle. The intracellular levels of dNTPs can influence various viral infections. This review provides a concise summary of the interactions between different viruses and the genes involved in dNTP metabolism.
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Affiliation(s)
- Shih-Yen Lo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
- Department of Laboratory Medicine, Buddhist Tzu Chi General Hospital, Hualien 970, Taiwan
| | - Meng-Jiun Lai
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
| | - Chee-Hing Yang
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
- Department of Microbiology and Immunology, School of Medicine, Tzu Chi University, Hualien 970, Taiwan
| | - Hui-Chun Li
- Department of Biochemistry, School of Medicine, Tzu Chi University, Hualien 970, Taiwan
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3
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Rashid F, Zaongo SD, Iqbal H, Harypursat V, Song F, Chen Y. Interactions between HIV proteins and host restriction factors: implications for potential therapeutic intervention in HIV infection. Front Immunol 2024; 15:1390650. [PMID: 39221250 PMCID: PMC11361988 DOI: 10.3389/fimmu.2024.1390650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 07/22/2024] [Indexed: 09/04/2024] Open
Abstract
Different host proteins target different HIV proteins and antagonize their functions, depending on the stage of the HIV life cycle and the stage of infection. Concurrently, HIV proteins also target and antagonize various different host proteins to facilitate HIV replication within host cells. The preceding quite specific area of knowledge in HIV pathogenesis, however, remains insufficiently understood. We therefore propose, in this review article, to examine and discuss the HIV proteins that counteract those host restriction proteins which results directly in increased infectivity of HIV. We elaborate on HIV proteins that antagonize host cellular proteins to promote HIV replication, and thus HIV infection. We examine the functions and mechanisms via which Nef, Vif, Vpu, Env, Vpr, and Vpx counteract host proteins such as Ser5, PSGL-1, IFITMS, A3G, tetherin, GBP5, SAMHD1, STING, HUSH, REAF, and TET2 to increase HIV infectivity. Nef antagonizes three host proteins, viz., Ser5, PSGL1, and IFITIMs, while Vpx also antagonizes three host restriction factors, viz., SAMHD1, STING, and HUSH complex; therefore, these proteins may be potential candidates for therapeutic intervention in HIV infection. Tetherin is targeted by Vpu and Env, PSGL1 is targeted by Nef and Vpu, while Ser5 is targeted by Nef and Env proteins. Finally, conclusive remarks and future perspectives are also presented.
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Affiliation(s)
- Farooq Rashid
- Department of Infectious Diseases, Chongqing Public Health Medical Center, Chongqing, China
| | - Silvere D. Zaongo
- Department of Infectious Diseases, Chongqing Public Health Medical Center, Chongqing, China
| | - Hifza Iqbal
- School of science, University of Management and Technology, Lahore, Pakistan
| | - Vijay Harypursat
- Department of Infectious Diseases, Chongqing Public Health Medical Center, Chongqing, China
| | - Fangzhou Song
- Basic Medicine College, Chongqing Medical University, Chongqing, China
| | - Yaokai Chen
- Department of Infectious Diseases, Chongqing Public Health Medical Center, Chongqing, China
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4
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Moezpoor MR, Stevenson M. Help or Hinder: Protein Host Factors That Impact HIV-1 Replication. Viruses 2024; 16:1281. [PMID: 39205255 PMCID: PMC11360189 DOI: 10.3390/v16081281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Revised: 08/05/2024] [Accepted: 08/08/2024] [Indexed: 09/04/2024] Open
Abstract
Interactions between human immunodeficiency virus type 1 (HIV-1) and the host factors or restriction factors of its target cells determine the cell's susceptibility to, and outcome of, infection. Factors intrinsic to the cell are involved at every step of the HIV-1 replication cycle, contributing to productive infection and replication, or severely attenuating the chances of success. Furthermore, factors unique to certain cell types contribute to the differences in infection between these cell types. Understanding the involvement of these factors in HIV-1 infection is a key requirement for the development of anti-HIV-1 therapies. As the list of factors grows, and the dynamic interactions between these factors and the virus are elucidated, comprehensive and up-to-date summaries that recount the knowledge gathered after decades of research are beneficial to the field, displaying what is known so that researchers can build off the groundwork of others to investigate what is unknown. Herein, we aim to provide a review focusing on protein host factors, both well-known and relatively new, that impact HIV-1 replication in a positive or negative manner at each stage of the replication cycle, highlighting factors unique to the various HIV-1 target cell types where appropriate.
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Affiliation(s)
- Michael Rameen Moezpoor
- Department of Microbiology and Immunology, University of Miami Leonard M. Miller School of Medicine, Miami, FL 33136, USA
| | - Mario Stevenson
- Raymond F. Schinazi and Family Endowed Chair in Biomedicine; Professor of Medicine; Director, Institute of AIDS and Emerging Infectious Diseases; Department of Microbiology and Immunology, University of Miami Leonard M. Miller School of Medicine, Life Science Technology Park, 1951 NW 7th Avenue, Room 2331B, Suite 200, Miami, FL 33136, USA;
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Arribas L, Menéndez-Arias L, Betancor G. May I Help You with Your Coat? HIV-1 Capsid Uncoating and Reverse Transcription. Int J Mol Sci 2024; 25:7167. [PMID: 39000271 PMCID: PMC11241228 DOI: 10.3390/ijms25137167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Revised: 06/26/2024] [Accepted: 06/27/2024] [Indexed: 07/16/2024] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) capsid is a protein core formed by multiple copies of the viral capsid (CA) protein. Inside the capsid, HIV-1 harbours all the viral components required for replication, including the genomic RNA and viral enzymes reverse transcriptase (RT) and integrase (IN). Upon infection, the RT transforms the genomic RNA into a double-stranded DNA molecule that is subsequently integrated into the host chromosome by IN. For this to happen, the viral capsid must open and release the viral DNA, in a process known as uncoating. Capsid plays a key role during the initial stages of HIV-1 replication; therefore, its stability is intimately related to infection efficiency, and untimely uncoating results in reverse transcription defects. How and where uncoating takes place and its relationship with reverse transcription is not fully understood, but the recent development of novel biochemical and cellular approaches has provided unprecedented detail on these processes. In this review, we present the latest findings on the intricate link between capsid stability, reverse transcription and uncoating, the different models proposed over the years for capsid uncoating, and the role played by other cellular factors on these processes.
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Affiliation(s)
- Laura Arribas
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS), Universidad de Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain;
| | - Luis Menéndez-Arias
- Centro de Biología Molecular “Severo Ochoa” (Consejo Superior de Investigaciones Científicas & Universidad Autónoma de Madrid), 28049 Madrid, Spain;
| | - Gilberto Betancor
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias (IUIBS), Universidad de Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain;
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Ananth S, Ambiel I, Schifferdecker S, Müller TG, Wratil PR, Mejias-Perez E, Kräusslich HG, Müller B, Keppler OT, Fackler OT. Spatial resolution of HIV-1 post-entry steps in resting CD4 T cells. Cell Rep 2024; 43:113941. [PMID: 38478523 DOI: 10.1016/j.celrep.2024.113941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/20/2023] [Accepted: 02/26/2024] [Indexed: 04/02/2024] Open
Abstract
Resting CD4 T cells resist productive HIV-1 infection. The HIV-2/simian immunodeficiency virus protein viral accessory protein X (Vpx) renders these cells permissive to infection, presumably by alleviating blocks at cytoplasmic reverse transcription and subsequent nuclear import of reverse-transcription/pre-integration complexes (RTC/PICs). Here, spatial analyses using quantitative virus imaging techniques reveal that HIV-1 capsids containing RTC/PICs are readily imported into the nucleus, recruit the host dependency factor CPSF6, and translocate to nuclear speckles in resting CD4 T cells. Reverse transcription, however, remains incomplete, impeding proviral integration and viral gene expression. Vpx or pharmacological inhibition of the deoxynucleotide triphosphohydrolase (dNTPase) activity of the restriction factor SAM domain and HD domain-containing protein 1 (SAMHD1) increases levels of nuclear reverse-transcribed cDNA and facilitates HIV-1 integration. Nuclear import and intranuclear transport of viral complexes therefore do not pose important blocks to HIV-1 in resting CD4 T cells, and the limitation to reverse transcription by SAMHD1's dNTPase activity constitutes the main pre-integration block to infection.
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Affiliation(s)
- Swetha Ananth
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Integrative Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany
| | - Ina Ambiel
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Integrative Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany
| | - Sandra Schifferdecker
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany
| | - Thorsten G Müller
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany
| | - Paul R Wratil
- Max von Pettenkofer Institute and Gene Center, Virology, National Reference Center for Retroviruses, Ludwig-Maximilians-Universität München, Munich, Germany; German Centre for Infection Research (DZIF), Partner Site München, Munich, Germany
| | - Ernesto Mejias-Perez
- Max von Pettenkofer Institute and Gene Center, Virology, National Reference Center for Retroviruses, Ludwig-Maximilians-Universität München, Munich, Germany; German Centre for Infection Research (DZIF), Partner Site München, Munich, Germany
| | - Hans-Georg Kräusslich
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany; German Centre for Infection Research (DZIF), Partner Site Heidelberg, Heidelberg, Germany
| | - Barbara Müller
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany
| | - Oliver T Keppler
- Max von Pettenkofer Institute and Gene Center, Virology, National Reference Center for Retroviruses, Ludwig-Maximilians-Universität München, Munich, Germany; German Centre for Infection Research (DZIF), Partner Site München, Munich, Germany
| | - Oliver T Fackler
- Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Integrative Virology, Center of Integrative Infectious Disease Research (CIID), Heidelberg, Germany; German Centre for Infection Research (DZIF), Partner Site Heidelberg, Heidelberg, Germany.
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7
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Zhao Z, Han S, Zhang Q, Wang Y, Yue K, Abbas S, He H. Impaired influenza A virus replication by the host restriction factor SAMHD1 which inhibited by PA-mediated dephosphorylation of the host transcription factor IRF3. Virol J 2024; 21:33. [PMID: 38287375 PMCID: PMC10826253 DOI: 10.1186/s12985-024-02295-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 01/11/2024] [Indexed: 01/31/2024] Open
Abstract
BACKGROUND Influenza A virus (IAV) can cause severe and life-threatening illness in humans and animals. Therefore, it is important to search for host antiviral proteins and elucidate their antiviral mechanisms for the development of potential treatments. As a part of human innate immunity, host restriction factors can inhibit the replication of viruses, among which SAM and HD domain containing deoxynucleoside triphosphate triphosphohydrolase 1 (SAMHD1) can restrict the replication of viruses, such as HIV and enterovirus EV71. Viruses also developed countermeasures in the arms race with their hosts. There are few reports about whether SAMHD1 has a restriction effect on IAV. METHODS To investigate the impact of IAV infection on SAMHD1 expression in A549 cells, we infected A549 cells with a varying multiplicity of infection (MOI) of IAV and collected cell samples at different time points for WB and RT-qPCR analysis to detect viral protein and SAMHD1 levels. The virus replication level in the cell culture supernatant was determined using TCID50 assay. Luciferase assay was used to reveal that H5N1 virus polymerase acidic protein (PA) affected the activity of the SAMHD1 promoter. To assess the antiviral capacity of SAMHD1, we generated a knockdown and overexpressed cell line for detecting H5N1 replication. RESULTS In this study, we observed that SAMHD1 can restrict the intracellular replication of H5N1 and that the H5N1 viral protein PA can downregulate the expression of SAMHD1 by affecting SAMHD1 transcriptional promoter activity. We also found that SAMHD1's ability to restrict H5N1 is related to phosphorylation at 592-tyrosine. CONCLUSIONS In conclusion, we found that SAMHD1 may affect the replication of IAVs as a host restriction factor and be countered by PA. Furthermore, SAMHD1 may be a potential target for developing antiviral drugs.
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Affiliation(s)
- Zhilei Zhao
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shuyi Han
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Qingxun Zhang
- Beijing Milu Ecological Research Center, Beijing, 100076, China
| | - Ye Wang
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Kening Yue
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Salbia Abbas
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Hongxuan He
- National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
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Schüssler M, Schott K, Fuchs NV, Oo A, Zahadi M, Rauch P, Kim B, König R. Gene editing of SAMHD1 in macrophage-like cells reveals complex relationships between SAMHD1 phospho-regulation, HIV-1 restriction, and cellular dNTP levels. mBio 2023; 14:e0225223. [PMID: 37800914 PMCID: PMC10653793 DOI: 10.1128/mbio.02252-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE We introduce BLaER1 cells as an alternative myeloid cell model in combination with CRISPR/Cas9-mediated gene editing to study the influence of sterile α motif and HD domain-containing protein 1 (SAMHD1) T592 phosphorylation on anti-viral restriction and the control of cellular dNTP levels in an endogenous, physiologically relevant context. A proper understanding of the mechanism of the anti-viral function of SAMHD1 will provide attractive strategies aiming at selectively manipulating SAMHD1 without affecting other cellular functions. Even more, our toolkit may inspire further genetic analysis and investigation of restriction factors inhibiting retroviruses and their cellular function and regulation, leading to a deeper understanding of intrinsic anti-viral immunity.
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Affiliation(s)
- Moritz Schüssler
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Kerstin Schott
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Adrian Oo
- Department of Pediatrics, Emory University, Atlanta, Georgia, USA
| | - Morssal Zahadi
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Paula Rauch
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Baek Kim
- Department of Pediatrics, Emory University, Atlanta, Georgia, USA
- Center for Drug Discovery, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
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9
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Schüssler M, Schott K, Fuchs NV, Oo A, Zahadi M, Rauch P, Kim B, König R. Gene editing of SAMHD1 in macrophage-like cells reveals complex relationships between SAMHD1 phospho-regulation, HIV-1 restriction and cellular dNTP levels. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.24.554731. [PMID: 37662193 PMCID: PMC10473771 DOI: 10.1101/2023.08.24.554731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Sterile α motif (SAM) and HD domain-containing protein 1 (SAMHD1) is a dNTP triphosphate triphosphohydrolase (dNTPase) and a potent restriction factor for immunodeficiency virus 1 (HIV-1), active in myeloid and resting CD4+ T cells. The anti-viral activity of SAMHD1 is regulated by dephosphorylation of the residue T592. However, the impact of T592 phosphorylation on dNTPase activity is still under debate. Whether additional cellular functions of SAMHD1 impact anti-viral restriction is not completely understood. We report BLaER1 cells as a novel human macrophage HIV-1 infection model combined with CRISPR/Cas9 knock-in (KI) introducing specific mutations into the SAMHD1 locus to study mutations in a physiological context. Transdifferentiated BLaER1 cells harbor active dephosphorylated SAMHD1 that blocks HIV-1 reporter virus infection. As expected, homozygous T592E mutation, but not T592A, relieved a block to HIV-1 reverse transcription. Co-delivery of VLP-Vpx to SAMHD1 T592E KI mutant cells did not further enhance HIV-1 infection indicating the absence of an additional SAMHD1-mediated antiviral activity independent of T592 de-phosphorylation. T592E KI cells retained dNTP levels similar to WT cells indicating uncoupling of anti-viral and dNTPase activity of SAMHD1. The integrity of the catalytic site in SAMHD1 was critical for anti-viral activity, yet poor correlation of HIV-1 restriction and global cellular dNTP levels was observed in cells harboring catalytic core mutations. Together, we emphasize the complexity of the relationship between HIV-1 restriction, SAMHD1 enzymatic function and T592 phospho-regulation and provide novel tools for investigation in an endogenous and physiological context.
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Affiliation(s)
- Moritz Schüssler
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Kerstin Schott
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | | | - Adrian Oo
- Department of Pediatrics, Emory University, Atlanta, USA
| | - Morssal Zahadi
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Paula Rauch
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
| | - Baek Kim
- Department of Pediatrics, Emory University, Atlanta, USA
- Center for Drug Discovery, Children’s Healthcare of Atlanta, Atlanta, USA
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, Langen, Germany
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10
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Tsai MHC, Caswell SJ, Morris ER, Mann MC, Pennell S, Kelly G, Groom HCT, Taylor IA, Bishop KN. Attenuation of reverse transcriptase facilitates SAMHD1 restriction of HIV-1 in cycling cells. Retrovirology 2023; 20:5. [PMID: 37127613 PMCID: PMC10150492 DOI: 10.1186/s12977-023-00620-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 04/06/2023] [Indexed: 05/03/2023] Open
Abstract
BACKGROUND SAMHD1 is a deoxynucleotide triphosphohydrolase that restricts replication of HIV-1 in differentiated leucocytes. HIV-1 is not restricted in cycling cells and it has been proposed that this is due to phosphorylation of SAMHD1 at T592 in these cells inactivating the enzymatic activity. To distinguish between theories for how SAMHD1 restricts HIV-1 in differentiated but not cycling cells, we analysed the effects of substitutions at T592 on restriction and dNTP levels in both cycling and differentiated cells as well as tetramer stability and enzymatic activity in vitro. RESULTS We first showed that HIV-1 restriction was not due to SAMHD1 nuclease activity. We then characterised a panel of SAMHD1 T592 mutants and divided them into three classes. We found that a subset of mutants lost their ability to restrict HIV-1 in differentiated cells which generally corresponded with a decrease in triphosphohydrolase activity and/or tetramer stability in vitro. Interestingly, no T592 mutants were able to restrict WT HIV-1 in cycling cells, despite not being regulated by phosphorylation and retaining their ability to hydrolyse dNTPs. Lowering dNTP levels by addition of hydroxyurea did not give rise to restriction. Compellingly however, HIV-1 RT mutants with reduced affinity for dNTPs were significantly restricted by wild-type and T592 mutant SAMHD1 in both cycling U937 cells and Jurkat T-cells. Restriction correlated with reverse transcription levels. CONCLUSIONS Altogether, we found that the amino acid at residue 592 has a strong effect on tetramer formation and, although this is not a simple "on/off" switch, this does correlate with the ability of SAMHD1 to restrict HIV-1 replication in differentiated cells. However, preventing phosphorylation of SAMHD1 and/or lowering dNTP levels by adding hydroxyurea was not enough to restore restriction in cycling cells. Nonetheless, lowering the affinity of HIV-1 RT for dNTPs, showed that restriction is mediated by dNTP levels and we were able to observe for the first time that SAMHD1 is active and capable of inhibiting HIV-1 replication in cycling cells, if the affinity of RT for dNTPs is reduced. This suggests that the very high affinity of HIV-1 RT for dNTPs prevents HIV-1 restriction by SAMHD1 in cycling cells.
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Affiliation(s)
- Ming-Han C Tsai
- Retroviral Replication Laboratory, The Francis Crick Institute, London, UK
- LabGenius, London, UK
| | - Sarah J Caswell
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
- AstraZeneca, Granta Park, Cambridge, UK
| | - Elizabeth R Morris
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
- Department of Biosciences, University of Durham, Durham, UK
| | - Melanie C Mann
- Retroviral Replication Laboratory, The Francis Crick Institute, London, UK
- Sartorius, Ulm, Germany
| | - Simon Pennell
- Structural Biology of DNA-Damage Signalling Laboratory, The Francis Crick Institute, London, UK
- MRC London Institute of Medical Sciences, London, UK
| | - Geoff Kelly
- The Medical Research Council Biomedical NMR Centre, The Francis Crick Institute, London, UK
| | - Harriet C T Groom
- Retroviral Replication Laboratory, The Francis Crick Institute, London, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
| | - Kate N Bishop
- Retroviral Replication Laboratory, The Francis Crick Institute, London, UK.
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11
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Host Cell Restriction Factors Blocking Efficient Vector Transduction: Challenges in Lentiviral and Adeno-Associated Vector Based Gene Therapies. Cells 2023; 12:cells12050732. [PMID: 36899868 PMCID: PMC10001033 DOI: 10.3390/cells12050732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/02/2023] [Accepted: 02/08/2023] [Indexed: 03/03/2023] Open
Abstract
Gene therapy relies on the delivery of genetic material to the patient's cells in order to provide a therapeutic treatment. Two of the currently most used and efficient delivery systems are the lentiviral (LV) and adeno-associated virus (AAV) vectors. Gene therapy vectors must successfully attach, enter uncoated, and escape host restriction factors (RFs), before reaching the nucleus and effectively deliver the therapeutic genetic instructions to the cell. Some of these RFs are ubiquitously expressed in mammalian cells, while others are cell-specific, and others still are expressed only upon induction by danger signals as type I interferons. Cell restriction factors have evolved to protect the organism against infectious diseases and tissue damage. These restriction factors can be intrinsic, directly acting on the vector, or related with the innate immune response system, acting indirectly through the induction of interferons, but both are intertwined. The innate immunity is the first line of defense against pathogens and, as such cells derived from myeloid progenitors (but not only), are well equipped with RFs to detect pathogen-associated molecular patterns (PAMPs). In addition, some non-professional cells, such as epithelial cells, endothelial cells, and fibroblasts, play major roles in pathogen recognition. Unsurprisingly, foreign DNA and RNA molecules are among the most detected PAMPs. Here, we review and discuss identified RFs that block LV and AAV vector transduction, hindering their therapeutic efficacy.
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12
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Schumann T, Ramon SC, Schubert N, Mayo MA, Hega M, Maser KI, Ada SR, Sydow L, Hajikazemi M, Badstübner M, Müller P, Ge Y, Shakeri F, Buness A, Rupf B, Lienenklaus S, Utess B, Muhandes L, Haase M, Rupp L, Schmitz M, Gramberg T, Manel N, Hartmann G, Zillinger T, Kato H, Bauer S, Gerbaulet A, Paeschke K, Roers A, Behrendt R. Deficiency for SAMHD1 activates MDA5 in a cGAS/STING-dependent manner. J Exp Med 2022; 220:213670. [PMID: 36346347 PMCID: PMC9648672 DOI: 10.1084/jem.20220829] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 09/01/2022] [Accepted: 10/06/2022] [Indexed: 11/09/2022] Open
Abstract
Defects in nucleic acid metabolizing enzymes can lead to spontaneous but selective activation of either cGAS/STING or RIG-like receptor (RLR) signaling, causing type I interferon-driven inflammatory diseases. In these pathophysiological conditions, activation of the DNA sensor cGAS and IFN production are linked to spontaneous DNA damage. Physiological, or tonic, IFN signaling on the other hand is essential to functionally prime nucleic acid sensing pathways. Here, we show that low-level chronic DNA damage in mice lacking the Aicardi-Goutières syndrome gene SAMHD1 reduced tumor-free survival when crossed to a p53-deficient, but not to a DNA mismatch repair-deficient background. Increased DNA damage did not result in higher levels of type I interferon. Instead, we found that the chronic interferon response in SAMHD1-deficient mice was driven by the MDA5/MAVS pathway but required functional priming through the cGAS/STING pathway. Our work positions cGAS/STING upstream of tonic IFN signaling in Samhd1-deficient mice and highlights an important role of the pathway in physiological and pathophysiological innate immune priming.
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Affiliation(s)
- Tina Schumann
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Santiago Costas Ramon
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Nadja Schubert
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Mohamad Aref Mayo
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Melanie Hega
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Katharina Isabell Maser
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Servi-Remzi Ada
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Lukas Sydow
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Mona Hajikazemi
- Clinic of Internal Medicine III, Oncology, Hematology, Rheumatology and Clinical Immunology, University Hospital Bonn, Bonn, Germany
| | - Markus Badstübner
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Patrick Müller
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Yan Ge
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,Institute for Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Farhad Shakeri
- Institute for Medical Biometry, Informatics and Epidemiology, Medical Faculty, University of Bonn, Bonn, Germany,Institute for Genomic Statistics and Bioinformatics, Medical Faculty, University of Bonn, Bonn, Germany
| | - Andreas Buness
- Institute for Medical Biometry, Informatics and Epidemiology, Medical Faculty, University of Bonn, Bonn, Germany,Institute for Genomic Statistics and Bioinformatics, Medical Faculty, University of Bonn, Bonn, Germany
| | - Benjamin Rupf
- Institute for Immunology, Philipps-University Marburg, Marburg, Germany
| | - Stefan Lienenklaus
- Institute of Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | - Barbara Utess
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Lina Muhandes
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Michael Haase
- Department of Pediatric Surgery, University Hospital Dresden, Dresden, Germany
| | - Luise Rupp
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Marc Schmitz
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,National Center for Tumor Diseases, Partner Site Dresden, Dresden, Germany,German Cancer Consortium, Partner Site Dresden, and German Cancer Research Center, Heidelberg, Germany
| | - Thomas Gramberg
- Institute of Clinical and Molecular Virology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Nicolas Manel
- Institut national de la santé et de la recherche médicale U932, Institut Curie, Paris Sciences et Lettres Research University, Paris, France
| | - Gunther Hartmann
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Thomas Zillinger
- Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Hiroki Kato
- Institute of Cardiovascular Immunology, Medical Faculty, University Hospital Bonn, Bonn, Germany
| | - Stefan Bauer
- Institute for Immunology, Philipps-University Marburg, Marburg, Germany
| | - Alexander Gerbaulet
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Katrin Paeschke
- Clinic of Internal Medicine III, Oncology, Hematology, Rheumatology and Clinical Immunology, University Hospital Bonn, Bonn, Germany
| | - Axel Roers
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,Institute for Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Rayk Behrendt
- Institute for Immunology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany,Institute for Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany,Correspondence to Rayk Behrendt:
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13
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Huan C, Qu X, Li Z. Host Restrictive Factors Are the Emerging Storm Troopers Against Enterovirus: A Mini-Review. Front Immunol 2022; 13:910780. [PMID: 35603180 PMCID: PMC9114347 DOI: 10.3389/fimmu.2022.910780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 04/12/2022] [Indexed: 11/27/2022] Open
Abstract
Enterovirus infection continues to be a global health problem. The lack of specific drugs and broad-spectrum vaccines means an urgent need to develop effective strategies against enteroviruses. Host restrictive factors are a class of intrinsic host antiviral factors that have been broadly defined and investigated during HIV infections and have great significance for drug development and treatment design. In recent years, the essential role of host restrictive factors in regulating enteroviral infections has been gradually recognized and investigated. An increasing number of studies have shown that host-restrictive factors regulate multiple steps in the life cycle of enteroviruses. This mini-review discusses the restrictive factors against enteroviruses, their antiviral mechanism, and the arms race between them and enteroviruses. We also summarise the pathways that enteroviruses use to impair host antiviral signals. This mini-review characterizes the essential role of host restriction factors in enterovirus infections, which provides ideas and potential targets for antiviral drug design by regulating host restrictive factors. It also reveals potential future research on the interplay between host restrictive factors and enteroviruses.
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Affiliation(s)
- Chen Huan
- Center of Infectious Diseases and Pathogen Biology, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin University, Changchun, China
| | - Xinglong Qu
- Respiratory Department of the First Hospital of Jilin University, Changchun, China
| | - Zhaolong Li
- Center of Infectious Diseases and Pathogen Biology, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of The Ministry of Education, The First Hospital of Jilin University, Changchun, China
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14
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Mohamed A, Bakir T, Al-Hawel H, Al-Sharif I, Bakheet R, Kouser L, Murugaiah V, Al-Mozaini M. HIV-2 Vpx neutralizes host restriction factor SAMHD1 to promote viral pathogenesis. Sci Rep 2021; 11:20984. [PMID: 34697376 PMCID: PMC8545964 DOI: 10.1038/s41598-021-00415-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 10/12/2021] [Indexed: 11/21/2022] Open
Abstract
SAMHD1, a human host factor found in myeloid cells which restricts HIV-1 replication. It depletes the dNTPs pool for viral cDNA syntheses, thus preventing the viral replication in the cells. The viral accessory protein, Vpx, exists only in SIVmac/HIV-2 particles. Vpx in SIVmac can induce proteosomal degradation of SAMHD1, which then leads to a decrease in the cytoplasmic dNTP pool. The protein-protein interaction between Vpx and SAMHD1 and its consequences are still unclear. Methods: In this study, we cloned, for the first time, Vpx gene from a HIV-2 infected patient and found up to 30% sequence variation compared to known HIV-2 strains. We then analyzed the role of SAMHD1 protein expression in transfected THP-1 and U937 cells by transfecting with the Vpx gene derived from SIVmac, HIV-2 from the NIH sample as well as HIV-2 from a Saudi patient. We found that Vpx gene expression led to reduced levels of intracellular SAMHD1. When the supernatants of the transfected cell lines were examined for secreted cytokines, chemokines and growth factors, Vpx expression seemed to be suppressive of pro-inflammatory response, and skewed the immune response towards an anti-inflammatory response. These results suggest that Vpx can act at two levels: clearance of intracellular restriction factor and suppression of cytokine storm: both aimed at long-term latency and host-pathogen stand-off, suggesting that Vpx is likely to be a potential therapeutic target.
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Affiliation(s)
- Ahlam Mohamed
- Immunocompromised Host Research Section, Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, PO Box 3354 (MBC-03), Riyadh, 11211, Kingdom of Saudi Arabia
| | - Talal Bakir
- Department of Clinical Laboratories Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Huda Al-Hawel
- Immunocompromised Host Research Section, Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, PO Box 3354 (MBC-03), Riyadh, 11211, Kingdom of Saudi Arabia
| | - Ibtihaj Al-Sharif
- Immunocompromised Host Research Section, Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, PO Box 3354 (MBC-03), Riyadh, 11211, Kingdom of Saudi Arabia
| | - Razan Bakheet
- Immunocompromised Host Research Section, Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, PO Box 3354 (MBC-03), Riyadh, 11211, Kingdom of Saudi Arabia
| | | | - Valarmathy Murugaiah
- Biosciences, College of Health, Medicine and Life Sciences, Brunel University London, London, UK
| | - Maha Al-Mozaini
- Immunocompromised Host Research Section, Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, PO Box 3354 (MBC-03), Riyadh, 11211, Kingdom of Saudi Arabia.
- Department of Clinical Laboratories Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
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15
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SAMHD1 Inhibits Multiple Enteroviruses by Interfering with the Interaction between VP1 and VP2 Proteins. J Virol 2021; 95:e0062021. [PMID: 33883225 DOI: 10.1128/jvi.00620-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Sterile alpha motif and histidine-aspartic acid domain-containing protein 1 (SAMHD1) possesses multiple biological activities such as virus restriction, innate immunity regulation, and autoimmunity. Our previous study demonstrated that SAMHD1 potently inhibits the replication of enterovirus 71 (EV71). In this study, we observed that SAMHD1 also restricts multiple enteroviruses (EVs), including coxsackievirus A16 (CA16) and enterovirus D68 (EVD68), but not coxsackievirus A6 (CA6). Mechanistically, SAMHD1 competitively interacted with the same domain in VP1 that binds to VP2 of EV71 and EVD68, thereby interfering with the interaction between VP1 and VP2 , and therefore viral assembly. Moreover, we showed that the SAMHD1 T592A mutant maintained the EV71 inhibitory effect by attenuating the interaction between VP1 and VP2, whereas the T592D mutant failed to. We also demonstrated that SAMHD1 could not inhibit CA6 because a different binding site is required for the SAMHD1 and VP1 interaction. Our findings reveal the mechanism of SAMHD1 inhibition of multiple EVs, and this could potentially be important for developing drugs against a broad range of EVs. IMPORTANCE Enterovirus causes a wide variety of diseases, such as hand, foot, and mouth disease (HFMD), which is a severe public problem threatening children under 5 years. Therefore, identifying essential genes which restrict EV infection and exploring the underlying mechanisms are necessary to develop an effective strategy to inhibit EV infection. In this study, we report that host restrictive factor SAMHD1 has broad-spectrum antiviral activity against EV71, CA16, and EVD68 independent of its well-known deoxynucleoside triphosphate triphosphohydrolase (dNTPase) or RNase activity. Mechanistically, SAMHD1 restricts EVs by competitively interacting with the same domain in VP1 that binds to VP2 of EVs, thereby interfering with the interaction between VP1 and VP2, and therefore viral assembly. In contrast, we also demonstrated that SAMHD1 could not inhibit CA6 because a different binding site is required for the SAMHD1 and CA6 VP1 interaction. Our study reveals a novel mechanism for the SAMHD1 anti-EV replication activity.
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16
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SAMHD1 … and Viral Ways around It. Viruses 2021; 13:v13030395. [PMID: 33801276 PMCID: PMC7999308 DOI: 10.3390/v13030395] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/24/2021] [Accepted: 02/25/2021] [Indexed: 12/19/2022] Open
Abstract
The SAM and HD domain-containing protein 1 (SAMHD1) is a dNTP triphosphohydrolase that plays a crucial role for a variety of different cellular functions. Besides balancing intracellular dNTP concentrations, facilitating DNA damage repair, and dampening excessive immune responses, SAMHD1 has been shown to act as a major restriction factor against various virus species. In addition to its well-described activity against retroviruses such as HIV-1, SAMHD1 has been identified to reduce the infectivity of different DNA viruses such as the herpesviruses CMV and EBV, the poxvirus VACV, or the hepadnavirus HBV. While some viruses are efficiently restricted by SAMHD1, others have developed evasion mechanisms that antagonize the antiviral activity of SAMHD1. Within this review, we summarize the different cellular functions of SAMHD1 and highlight the countermeasures viruses have evolved to neutralize the restriction factor SAMHD1.
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17
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Benayas B, Sastre I, López-Martín S, Oo A, Kim B, Bullido MJ, Aldudo J, Yáñez-Mó M. Tetraspanin CD81 regulates HSV-1 infection. Med Microbiol Immunol 2020; 209:489-498. [PMID: 32500359 PMCID: PMC7271138 DOI: 10.1007/s00430-020-00684-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 05/27/2020] [Indexed: 02/08/2023]
Abstract
Different members of the tetraspanin superfamily have been described to regulate different virus infectious cycles at several stages: viral entry, viral replication or virion exit or infectivity. In addition, tetraspanin CD81 regulates HIV reverse transcription through its association with the dNTP hydrolase SAMHD1. Here we aimed at analysing the role of CD81 in Herpes simplex virus 1 infectivity using a neuroblastoma cell model. For this purpose, we generated a CD81 KO cell line using the CRISPR/Cas9 technology. Despite being CD81 a plasma membrane protein, CD81 KO cells showed no defects in viral entry nor in the expression of early protein markers. In contrast, glycoprotein B and C, which require viral DNA replication for their expression, were significantly reduced in CD81 KO infected cells. Indeed, HSV-1 DNA replication and the formation of new infectious particles were severely compromised in CD81 KO cells. We could not detect significant changes in SAMHD1 total expression levels, but a relocalization into endosomal structures was observed in CD81 KO cells. In summary, CD81 KO cells showed impaired viral DNA replication and produced greatly diminished viral titers.
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Affiliation(s)
- Beatriz Benayas
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), 28006, Madrid, Spain
| | - Isabel Sastre
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain
- Centro de Investigacion Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Soraya López-Martín
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), 28006, Madrid, Spain
| | - Adrian Oo
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Baek Kim
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Maria J Bullido
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain
- Centro de Investigacion Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Instituto de Investigación Sanitaria "Hospital la Paz" (IdIPaz), Madrid, Spain
| | - Jesús Aldudo
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain.
- Centro de Investigacion Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
- Instituto de Investigación Sanitaria "Hospital la Paz" (IdIPaz), Madrid, Spain.
| | - María Yáñez-Mó
- Centro de Biología Molecular, "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, C/Nicolás Cabrera 1, 28049, Madrid, Spain.
- Centro de Biología Molecular Severo Ochoa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), 28006, Madrid, Spain.
- Departamento de Bioquímica y Biología Molecular, UAM, Centro de Biología Molecular Severo Ochoa, Lab 412, C/Nicolás Cabrera, 1, 28049, Madrid, Spain.
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18
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Restriction of exogenous DNA expression by SAMHD1. Sci Bull (Beijing) 2020; 65:573-586. [PMID: 36659189 DOI: 10.1016/j.scib.2019.12.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/09/2019] [Accepted: 11/19/2019] [Indexed: 01/21/2023]
Abstract
SAMHD1 (Sterile Alpha Motif and Histidine-aspartate Domain containing protein 1) has been documented as a host factor that restricts HIV-1 and some DNA viruses. In this work, we attempted to explore possible effects of SAMHD1 on exogenous DNA and show that SAMHD1 exerts a general inhibition on the expression of exogenous DNA in vitro and in mice. This inhibition is achieved through repressing transcription of exogenous DNA. Intriguingly, unlike SAMHD1's restriction of HIV-1, such restriction does not require the dNTPase or RNase activities, or T592 phosphorylation of SAMHD1. Mechanistically, SAMHD1 enhances the expression of interferon regulatory factor-1 (IRF1), while IRF1 upregulation was demonstrated to inhibit exogenous DNA expression in a similar fashion as SAMHD1. IFNλ1, whose induction has been associated with IRF1 activation, is dispensable for SAMHD1/IRF1-mediated restriction of exogenous DNA, and neither type I nor II interferons appear to be involved. We also demonstrate that SAMHD1/IRF1-mediated restriction can effectively inhibit hepatitis B virus (HBV) antigen expression and progeny virus production in mouse models. In conclusion, these data support restriction of exogenous DNA as a novel function of SAMHD1.
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19
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SAMHD1 Functions and Human Diseases. Viruses 2020; 12:v12040382. [PMID: 32244340 PMCID: PMC7232136 DOI: 10.3390/v12040382] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 12/12/2022] Open
Abstract
Deoxynucleoside triphosphate (dNTP) molecules are essential for the replication and maintenance of genomic information in both cells and a variety of viral pathogens. While the process of dNTP biosynthesis by cellular enzymes, such as ribonucleotide reductase (RNR) and thymidine kinase (TK), has been extensively investigated, a negative regulatory mechanism of dNTP pools was recently found to involve sterile alpha motif (SAM) domain and histidine-aspartate (HD) domain-containing protein 1, SAMHD1. When active, dNTP triphosphohydrolase activity of SAMHD1 degrades dNTPs into their 2'-deoxynucleoside (dN) and triphosphate subparts, steadily depleting intercellular dNTP pools. The differential expression levels and activation states of SAMHD1 in various cell types contributes to unique dNTP pools that either aid (i.e., dividing T cells) or restrict (i.e., nondividing macrophages) viral replication that consumes cellular dNTPs. Genetic mutations in SAMHD1 induce a rare inflammatory encephalopathy called Aicardi-Goutières syndrome (AGS), which phenotypically resembles viral infection. Recent publications have identified diverse roles for SAMHD1 in double-stranded break repair, genome stability, and the replication stress response through interferon signaling. Finally, a series of SAMHD1 mutations were also reported in various cancer cell types while why SAMHD1 is mutated in these cancer cells remains to investigated. Here, we reviewed a series of studies that have begun illuminating the highly diverse roles of SAMHD1 in virology, immunology, and cancer biology.
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20
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Li Z, Huan C, Wang H, Liu Y, Liu X, Su X, Yu J, Zhao Z, Yu XF, Zheng B, Zhang W. TRIM21-mediated proteasomal degradation of SAMHD1 regulates its antiviral activity. EMBO Rep 2020; 21:e47528. [PMID: 31797533 PMCID: PMC6944907 DOI: 10.15252/embr.201847528] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 10/09/2019] [Accepted: 11/13/2019] [Indexed: 01/01/2023] Open
Abstract
SAMHD1 possesses multiple functions, but whether cellular factors regulate SAMHD1 expression or its function remains not well characterized. Here, by investigating why cultured RD and HEK293T cells show different sensitivity to enterovirus 71 (EV71) infection, we demonstrate that SAMHD1 is a restriction factor for EV71. Importantly, we identify TRIM21, an E3 ubiquitin ligase, as a key regulator of SAMHD1, which specifically interacts and degrades SAMHD1 through the proteasomal pathway. However, TRIM21 has no effect on EV71 replication itself. Moreover, we prove that interferon production stimulated by EV71 infection induces increased TRIM21 and SAMHD1 expression, whereas increasing TRIM21 overrides SAMHD1 inhibition of EV71 in cells and in a neonatal mouse model. TRIM21-mediated degradation of SAMHD1 also affects SAMHD1-dependent restriction of HIV-1 and the regulation of interferon production. We further identify the functional domains in TRIM21 required for SAMHD1 binding and the ubiquitination site K622 in SAMHD1 and show that phosphorylation of SAMHD1 at T592 also blocks EV71 restriction. Our findings illuminate how EV71 overcomes SAMHD1 inhibition via the upregulation of TRIM21.
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Affiliation(s)
- Zhaolong Li
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Chen Huan
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Hong Wang
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Yue Liu
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Xin Liu
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Xing Su
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Jinghua Yu
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Zhilei Zhao
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Xiao-Fang Yu
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
- Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, Ministry of Education), Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Baisong Zheng
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
| | - Wenyan Zhang
- The First Hospital of Jilin University, Institute of Virology and AIDS Research, Changchun, China
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21
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Monit C, Morris ER, Ruis C, Szafran B, Thiltgen G, Tsai MHC, Mitchison NA, Bishop KN, Stoye JP, Taylor IA, Fassati A, Goldstein RA. Positive selection in dNTPase SAMHD1 throughout mammalian evolution. Proc Natl Acad Sci U S A 2019; 116:18647-18654. [PMID: 31451672 PMCID: PMC6744909 DOI: 10.1073/pnas.1908755116] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The vertebrate protein SAMHD1 is highly unusual in having roles in cellular metabolic regulation, antiviral restriction, and regulation of innate immunity. Its deoxynucleoside triphosphohydrolase activity regulates cellular dNTP concentration, reducing levels below those required by lentiviruses and other viruses to replicate. To counter this threat, some primate lentiviruses encode accessory proteins that bind SAMHD1 and induce its degradation; in turn, positive diversifying selection has been observed in regions bound by these lentiviral proteins, suggesting that primate SAMHD1 has coevolved to evade these countermeasures. Moreover, deleterious polymorphisms in human SAMHD1 are associated with autoimmune disease linked to uncontrolled DNA synthesis of endogenous retroelements. Little is known about how evolutionary pressures affect these different SAMHD1 functions. Here, we examine the deeper history of these interactions by testing whether evolutionary signatures in SAMHD1 extend to other mammalian groups and exploring the molecular basis of this coevolution. Using codon-based likelihood models, we find positive selection in SAMHD1 within each mammal lineage for which sequence data are available. We observe positive selection at sites clustered around T592, a residue that is phosphorylated to regulate SAMHD1 activity. We verify experimentally that mutations within this cluster affect catalytic rate and lentiviral restriction, suggesting that virus-host coevolution has required adaptations of enzymatic function. Thus, persistent positive selection may have involved the adaptation of SAMHD1 regulation to balance antiviral, metabolic, and innate immunity functions.
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Affiliation(s)
- Christopher Monit
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom
| | - Elizabeth R Morris
- Macromolecular Structure Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - Christopher Ruis
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom
| | - Bart Szafran
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - Grant Thiltgen
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom
| | - Ming-Han Chloe Tsai
- Retroviral Replication Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - N Avrion Mitchison
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom
| | - Kate N Bishop
- Retroviral Replication Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - Jonathan P Stoye
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | - Ariberto Fassati
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom;
| | - Richard A Goldstein
- Division of Infection and Immunity, University College London, WC1E 6BT London, United Kingdom;
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22
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Morris ER, Taylor IA. The missing link: allostery and catalysis in the anti-viral protein SAMHD1. Biochem Soc Trans 2019; 47:1013-1027. [PMID: 31296733 PMCID: PMC7045340 DOI: 10.1042/bst20180348] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 12/11/2022]
Abstract
Vertebrate protein SAMHD1 (sterile-α-motif and HD domain containing protein 1) regulates the cellular dNTP (2'-deoxynucleoside-5'-triphosphate) pool by catalysing the hydrolysis of dNTP into 2'-deoxynucleoside and triphosphate products. As an important regulator of cell proliferation and a key player in dNTP homeostasis, mutations to SAMHD1 are implicated in hypermutated cancers, and germline mutations are associated with Chronic Lymphocytic Leukaemia and the inflammatory disorder Aicardi-Goutières Syndrome. By limiting the supply of dNTPs for viral DNA synthesis, SAMHD1 also restricts the replication of several retroviruses, such as HIV-1, and some DNA viruses in dendritic and myeloid lineage cells and resting T-cells. SAMHD1 activity is regulated throughout the cell cycle, both at the level of protein expression and post-translationally, through phosphorylation. In addition, allosteric regulation further fine-tunes the catalytic activity of SAMHD1, with a nucleotide-activated homotetramer as the catalytically active form of the protein. In cells, GTP and dATP are the likely physiological activators of two adjacent allosteric sites, AL1 (GTP) and AL2 (dATP), that bridge monomer-monomer interfaces to stabilise the protein homotetramer. This review summarises the extensive X-ray crystallographic, biophysical and molecular dynamics experiments that have elucidated important features of allosteric regulation in SAMHD1. We present a comprehensive mechanism detailing the structural and protein dynamics components of the allosteric coupling between nucleotide-induced tetramerization and the catalysis of dNTP hydrolysis by SAMHD1.
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Affiliation(s)
- Elizabeth R Morris
- Macromolecular Structure Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, U.K.
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, U.K
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23
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Interplay between Intrinsic and Innate Immunity during HIV Infection. Cells 2019; 8:cells8080922. [PMID: 31426525 PMCID: PMC6721663 DOI: 10.3390/cells8080922] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023] Open
Abstract
Restriction factors are antiviral components of intrinsic immunity which constitute a first line of defense by blocking different steps of the human immunodeficiency virus (HIV) replication cycle. In immune cells, HIV infection is also sensed by several pattern recognition receptors (PRRs), leading to type I interferon (IFN-I) and inflammatory cytokines production that upregulate antiviral interferon-stimulated genes (ISGs). Several studies suggest a link between these two types of immunity. Indeed, restriction factors, that are generally interferon-inducible, are able to modulate immune responses. This review highlights recent knowledge of the interplay between restriction factors and immunity inducing antiviral defenses. Counteraction of this intrinsic and innate immunity by HIV viral proteins will also be discussed.
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24
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Wohnhaas CT, Leparc GG, Fernandez-Albert F, Kind D, Gantner F, Viollet C, Hildebrandt T, Baum P. DMSO cryopreservation is the method of choice to preserve cells for droplet-based single-cell RNA sequencing. Sci Rep 2019; 9:10699. [PMID: 31337793 PMCID: PMC6650608 DOI: 10.1038/s41598-019-46932-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/04/2019] [Indexed: 11/15/2022] Open
Abstract
Combining single-cell RNA sequencing (scRNA-seq) with upstream cell preservation procedures such as cryopreservation or methanol fixation has recently become more common. By separating cell handling and preparation, from downstream library generation, scRNA-seq workflows are more flexible and manageable. However, the inherent transcriptomic changes associated with cell preservation and how they may bias further downstream analysis remain unknown. Here, we present a side-by-side droplet-based scRNA-seq analysis, comparing the gold standard - fresh cells - to three different cell preservation workflows: dimethyl sulfoxide based cryopreservation, methanol fixation and CellCover reagent. Cryopreservation proved to be the most robust protocol, maximizing both cell integrity and low background ambient RNA. Importantly, gene expression profiles from fresh cells correlated most with those of cryopreserved cells. Such similarities were consistently observed across the tested cell lines (R ≥ 0.97), monocyte-derived macrophages (R = 0.97) and immune cells (R = 0.99). In contrast, both methanol fixation and CellCover preservation showed an increased ambient RNA background and an overall lower gene expression correlation to fresh cells. Thus, our results demonstrate the superiority of cryopreservation over other cell preservation methods. We expect our comparative study to provide single-cell omics researchers invaluable support when integrating cell preservation into their scRNA-seq studies.
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Affiliation(s)
- Christian T Wohnhaas
- Computational Biology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
| | - Germán G Leparc
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
| | | | - David Kind
- Computational Biology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
| | - Florian Gantner
- Department of Biology, University of Konstanz, 78457, Konstanz, Germany
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
| | - Coralie Viollet
- Computational Biology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
| | - Tobias Hildebrandt
- Computational Biology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany
| | - Patrick Baum
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397, Biberach, Germany.
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25
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Kong J, Wang MM, He SY, Peng X, Qin XH. Structural characterization and directed modification of Sus scrofa SAMHD1 reveal the mechanism underlying deoxynucleotide regulation. FEBS J 2019; 286:3844-3857. [PMID: 31152619 DOI: 10.1111/febs.14943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 03/12/2019] [Accepted: 05/30/2019] [Indexed: 12/12/2022]
Abstract
Sterile α-motif/histidine-aspartate domain-containing protein 1 (SAMHD1) is an intrinsic antiviral restriction factor known to play a vital role in preventing multiple viral infections and in the control of the cellular deoxynucleoside triphosphate (dNTP) pool. Human and mouse SAMHD1 have both been extensively studied; however, our knowledge on porcine SAMHD1 is limited. Here, we report our findings from comprehensive structural and functional studies on porcine SAMHD1. We determined the crystal structure of porcine SAMHD1 and showed that it forms a symmetric tetramer. Moreover, we modified the deoxynucleotide triphosphohydrolase (dNTPase) activity of SAMHD1 by site-directed mutagenesis based on the crystal structure, and obtained an artificial dimeric enzyme possessing high dNTPase activity. Taken together, our results define the mechanism underlying dNTP regulation and provide a deeper understanding of the regulation of porcine SAMHD1 functions. Directed modification of key residues based on the protein structure enhances the activity of the enzyme, which will be beneficial in the search for new antiviral strategies and for future translational applications.
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Affiliation(s)
- Jia Kong
- School of Chemical Engineering and Technology, Tianjin University, China.,School of Life Sciences, Tianjin University, China
| | - Mei-Mei Wang
- School of Life Sciences, Tianjin University, China
| | - Shuang-Yi He
- School of Life Sciences, Tianjin University, China
| | - Xin Peng
- School of Life Sciences, Tianjin University, China
| | - Xiao-Hong Qin
- School of Life Sciences, Tianjin University, China.,State Key Laboratory of Medicinal Chemical Biology, NanKai University, Tianjin, China
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26
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SAMHD1 Enhances Chikungunya and Zika Virus Replication in Human Skin Fibroblasts. Int J Mol Sci 2019; 20:ijms20071695. [PMID: 30959732 PMCID: PMC6480247 DOI: 10.3390/ijms20071695] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 03/23/2019] [Accepted: 04/03/2019] [Indexed: 01/19/2023] Open
Abstract
Chikungunya virus (CHIKV) and Zika virus (ZIKV) are emerging arboviruses that pose a worldwide threat to human health. Currently, neither vaccine nor antiviral treatment to control their infections is available. As the skin is a major viral entry site for arboviruses in the human host, we determined the global proteomic profile of CHIKV and ZIKV infections in human skin fibroblasts using Stable Isotope Labelling by Amino acids in Cell culture (SILAC)-based mass-spectrometry analysis. We show that the expression of the interferon-stimulated proteins MX1, IFIT1, IFIT3 and ISG15, as well as expression of defense response proteins DDX58, STAT1, OAS3, EIF2AK2 and SAMHD1 was significantly up-regulated in these cells upon infection with either virus. Exogenous expression of IFITs proteins markedly inhibited CHIKV and ZIKV replication which, accordingly, was restored following the abrogation of IFIT1 or IFIT3. Overexpression of SAMHD1 in cutaneous cells, or pretreatment of cells with the virus-like particles containing SAMHD1 restriction factor Vpx, resulted in a strong increase or inhibition, respectively, of both CHIKV and ZIKV replication. Moreover, silencing of SAMHD1 by specific SAMHD1-siRNA resulted in a marked decrease of viral RNA levels. Together, these results suggest that IFITs are involved in the restriction of replication of CHIKV and ZIKV and provide, as yet unreported, evidence for a proviral role of SAMHD1 in arbovirus infection of human skin cells.
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27
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Majer C, Schüssler JM, König R. Intertwined: SAMHD1 cellular functions, restriction, and viral evasion strategies. Med Microbiol Immunol 2019; 208:513-529. [PMID: 30879196 DOI: 10.1007/s00430-019-00593-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 03/08/2019] [Indexed: 01/01/2023]
Abstract
SAMHD1 was initially described for its ability to efficiently restrict HIV-1 replication in myeloid cells and resting CD4+ T cells. However, a growing body of evidence suggests that SAMHD1-mediated restriction is by far not limited to lentiviruses, but seems to be a general concept that applies to most retroviruses and at least a number of DNA viruses. SAMHD1 anti-viral activity was long believed to be solely due to its ability to deplete cellular dNTPs by enzymatic degradation. However, since its discovery, several new functions have been attributed to SAMHD1. It has been demonstrated to bind nucleic acids, to modulate innate immunity, as well as to participate in the DNA damage response and resolution of stalled replication forks. Consequently, it is likely that SAMHD1-mediated anti-viral activity is not or not exclusively mediated through its dNTPase activity. Therefore, in this review, we summarize current knowledge on SAMHD1 cellular functions and systematically discuss how these functions could contribute to the restriction of a broad range of viruses besides retroviruses: herpesviruses, poxviruses and hepatitis B virus. Furthermore, we aim to highlight different ways how viruses counteract SAMHD1-mediated restriction to bypass the SAMHD1-mediated block to viral infection.
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Affiliation(s)
- Catharina Majer
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany
| | | | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany. .,Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA. .,German Center for Infection Research (DZIF), 63225, Langen, Germany. .,Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany.
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28
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Profiling of LINE-1-Related Genes in Hepatocellular Carcinoma. Int J Mol Sci 2019; 20:ijms20030645. [PMID: 30717368 PMCID: PMC6387036 DOI: 10.3390/ijms20030645] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 01/26/2019] [Accepted: 01/29/2019] [Indexed: 12/14/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a prime public health concern that accounts for most of the primary liver malignancies in humans. The most common etiological factor of HCC is hepatitis B virus (HBV). Despite recent advances in treatment strategies, there has been little success in improving the survival of HCC patients. To develop a novel therapeutic approach, evaluation of a working hypothesis based on different viewpoints might be important. Long interspersed element 1 (L1) retrotransposons have been suggested to play a role in HCC. However, the molecular machineries that can modulate L1 biology in HBV-related HCC have not been well-evaluated. Here, we summarize the profiles of expression and/or activation status of L1-related genes in HBV-related HCC, and HBV- and HCC-related genes that may impact L1-mediated tumorigenesis. L1 restriction factors appear to be suppressed by HBV infection. Since some of the L1 restriction factors also limit HBV, these factors may be exhausted in HBV-infected cells, which causes de-suppression of L1. Several HBV- and HCC-related genes that interact with L1 can affect oncogenic processes. Thus, L1 may be a novel prime therapeutic target for HBV-related HCC. Studies in this area will provide insights into HCC and other types of cancers.
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29
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Colomer-Lluch M, Ruiz A, Moris A, Prado JG. Restriction Factors: From Intrinsic Viral Restriction to Shaping Cellular Immunity Against HIV-1. Front Immunol 2018; 9:2876. [PMID: 30574147 PMCID: PMC6291751 DOI: 10.3389/fimmu.2018.02876] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/22/2018] [Indexed: 01/20/2023] Open
Abstract
Antiviral restriction factors are host cellular proteins that constitute a first line of defense blocking viral replication and propagation. In addition to interfering at critical steps of the viral replication cycle, some restriction factors also act as innate sensors triggering innate responses against infections. Accumulating evidence suggests an additional role for restriction factors in promoting antiviral cellular immunity to combat viruses. Here, we review the recent progress in our understanding on how restriction factors, particularly APOBEC3G, SAMHD1, Tetherin, and TRIM5α have the cell-autonomous potential to induce cellular resistance against HIV-1 while promoting antiviral innate and adaptive immune responses. Also, we provide an overview of how these restriction factors may connect with protein degradation pathways to modulate anti-HIV-1 cellular immune responses, and we summarize the potential of restriction factors-based therapeutics. This review brings a global perspective on the influence of restrictions factors in intrinsic, innate, and also adaptive antiviral immunity opening up novel research avenues for therapeutic strategies in the fields of drug discovery, gene therapy, and vaccines to control viral infections.
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Affiliation(s)
- Marta Colomer-Lluch
- IrsiCaixa AIDS Research Institute, Germans Trias i Pujol Research Institute, Universitat Autonoma de Barcelona, Badalona, Spain
| | - Alba Ruiz
- IrsiCaixa AIDS Research Institute, Germans Trias i Pujol Research Institute, Universitat Autonoma de Barcelona, Badalona, Spain
| | - Arnaud Moris
- Sorbonne Université, INSERM U1135, CNRS ERL 8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Julia G Prado
- IrsiCaixa AIDS Research Institute, Germans Trias i Pujol Research Institute, Universitat Autonoma de Barcelona, Badalona, Spain
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30
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Chen S, Bonifati S, Qin Z, St Gelais C, Wu L. SAMHD1 Suppression of Antiviral Immune Responses. Trends Microbiol 2018; 27:254-267. [PMID: 30336972 DOI: 10.1016/j.tim.2018.09.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/17/2018] [Accepted: 09/26/2018] [Indexed: 12/18/2022]
Abstract
SAMHD1 is a host triphosphohydrolase that degrades intracellular deoxynucleoside triphosphates (dNTPs) to a lower level that restricts viral DNA synthesis, and thus prevents replication of diverse viruses in nondividing cells. Recent progress indicates that SAMHD1 negatively regulates antiviral innate immune responses and inflammation through interacting with various key proteins in immune signaling and DNA damage-repair pathways. SAMHD1 can also modulate antibody production in adaptive immune responses. In this review, we summarize how SAMHD1 regulates antiviral immune responses through distinct mechanisms, and discuss the implications of these new functions of SAMHD1. Furthermore, we propose important new questions and future directions that can advance functional and mechanistic studies of SAMHD1-mediated immune regulation during viral infections.
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Affiliation(s)
- Shuliang Chen
- School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China; Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Serena Bonifati
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Zhihua Qin
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Corine St Gelais
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Li Wu
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA; Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA.
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31
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Li M, Xu X, Jiang Z, Liu C, Shi X, Qi G, Li Y, Chen X, Huang Q, Mao H, Hu C. Fish SAMHD1 performs as an activator for IFN expression. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 86:138-146. [PMID: 29753769 DOI: 10.1016/j.dci.2018.05.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/11/2018] [Accepted: 05/07/2018] [Indexed: 06/08/2023]
Abstract
As a host limiting factor, Sterile Alpha Motif and Histidine-Aspartate Domain 1 protein (SAMHD1) is associated with IRF3-mediated antiviral and apoptotic responses in mammals. However, the antiviral mechanism of SAMHD1 remains indistinct in fish. In this study, we found the expression of Ctenopharyngodon idella SAMHD1 (MF326081) was up-regulated after transfection with poly I:C (dsRNA analog), B-DNA or Z-DNA into C. idella kidney cells (CIKs), but these expression profiles had no obvious change when the cells were incubated with these nucleic acids. These data may indicate that CiSAMHD1 participates in the intracellular PRR-mediated signaling pathway rather than extracellular PRR-mediated signaling pathway. Subcellular localization assay suggested that a part of over-expressed CiSAMHD1 were translocated from nuclear to cytoplasm when C. idella ovary cells (COs) were transfected with poly I:C, B-DNA or Z-DNA. Nucleic acid pulldown assays were performed to investigate the reason for nuclear-cytoplasm translocation of CiSAMHD1. The results showed that CiSAMHD1 had a high affinity with B-DNA, Z-DNA and ISD-PS (dsRNA analog). In addition, co-IP assays revealed the interaction of CiSAMHD1 with CiSTING (KF494194). Taken together, all these results suggest that grass carp SAMHD1 performs as an activator for innate immune response through STING-mediated signaling pathway.
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Affiliation(s)
- Meifeng Li
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Xiaowen Xu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Zeyin Jiang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Changxin Liu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Xiao Shi
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Guoqin Qi
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Yinping Li
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Xin Chen
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Qingli Huang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Huiling Mao
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China
| | - Chengyu Hu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang, 330031, China.
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32
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Martinez-Lopez A, Martin-Fernandez M, Buta S, Kim B, Bogunovic D, Diaz-Griffero F. SAMHD1 deficient human monocytes autonomously trigger type I interferon. Mol Immunol 2018; 101:450-460. [PMID: 30099227 DOI: 10.1016/j.molimm.2018.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 07/24/2018] [Accepted: 08/02/2018] [Indexed: 01/04/2023]
Abstract
Germline mutations in the human SAMHD1 gene cause the development of Aicardi-Goutières Syndrome (AGS), with a dominant feature being increased systemic type I interferon(IFN) production. Here we tested the state of type I IFN induction and response to, in SAMHD1 knockout (KO) human monocytic cells. SAMHD1 KO cells exhibited spontaneous transcription and translation of IFN-β and subsequent interferon-stimulated genes (ISGs) as compared to parental wild-type cells. This elevation of IFN-β and ISGs was abrogated via inhibition of the TBK1-IRF3 pathway in the SAMHD1 KO cells. In agreement, we found that SAMHD1 KO cells present high levels of phosphorylated TBK1 when compared to control cells. Moreover, addition of blocking antibody against type I IFN also reversed elevation of ISGs. These experiments suggested that SAMHD1 KO cells are persistently auto-stimulating the TBK1-IRF3 pathway, leading to an enhanced production of type I IFN and subsequent self-induction of ISGs.
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Affiliation(s)
- Alicia Martinez-Lopez
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, United States
| | - Marta Martin-Fernandez
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Sofija Buta
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Baek Kim
- Department of Pediatrics, Emory University, Atlanta, GA 30322, United States
| | - Dusan Bogunovic
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Felipe Diaz-Griffero
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, United States.
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33
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Lentiviral infection of proliferating brain macrophages in HIV and simian immunodeficiency virus encephalitis despite sterile alpha motif and histidine-aspartate domain-containing protein 1 expression. AIDS 2018; 32:965-974. [PMID: 29698322 PMCID: PMC5943146 DOI: 10.1097/qad.0000000000001793] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Objective: HIV-1 infection of the brain and related cognitive impairment remain prevalent in HIV-1-infected individuals despite combination antiretroviral therapy. Sterile alpha motif and histidine-aspartate domain-containing protein 1 (SAMHD1) is a newly identified host restriction factor that blocks the replication of HIV-1 and other retroviruses in myeloid cells. Cell cycle-regulated phosphorylation at residue Thr592 and viral protein X (Vpx)-mediated degradation of SAMHD1 have been shown to bypass SAMHD1 restriction in vitro. Herein, we investigated expression and phosphorylation of SAMHD1 in vivo in relation to macrophage infection and proliferation during the neuropathogenesis of HIV-1 and simian immunodeficiency virus (SIV) encephalitis. Methods: Using brain and other tissues from uninfected and SIV-infected macaques with or without encephalitis, we performed immunohistochemistry, multilabel fluorescence microscopy and western blot to examine the expression, localization and phosphorylation of SAMHD1. Results: The number of SAMHD1+ nuclei increased in encephalitic brains despite the presence of Vpx. Many of these cells were perivascular macrophages, although subsets of SAMHD1+ microglia and endothelial cells were also observed. The SAMHD1+ macrophages were shown to be both infected and proliferating. Moreover, the presence of cycling SAMHD1+ brain macrophages was confirmed in the tissue of HIV-1-infected patients with encephalitis. Finally, western blot analysis of brain-protein extracts from SIV-infected macaques showed that SAMHD1 protein exists in the brain mainly as an inactive Thr592-phosphorylated form. Conclusion: The ability of SAMHD1 to act as a restriction factor for SIV/HIV in the brain is likely bypassed in proliferating brain macrophages through the phosphorylation-mediated inactivation, not Vpx-mediated degradation of SAMHD1.
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Mauney CH, Hollis T. SAMHD1: Recurring roles in cell cycle, viral restriction, cancer, and innate immunity. Autoimmunity 2018; 51:96-110. [PMID: 29583030 PMCID: PMC6117824 DOI: 10.1080/08916934.2018.1454912] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 03/16/2018] [Indexed: 12/24/2022]
Abstract
Sterile alpha motif and histidine-aspartic acid domain-containing protein 1 (SAMHD1) is a deoxynucleotide triphosphate (dNTP) hydrolase that plays an important role in the homeostatic balance of cellular dNTPs. Its emerging role as an effector of innate immunity is affirmed by mutations in the SAMHD1 gene that cause the severe autoimmune disease, Aicardi-Goutieres syndrome (AGS) and that are linked to cancer. Additionally, SAMHD1 functions as a restriction factor for retroviruses, such as HIV. Here, we review the current biochemical and biological properties of the enzyme including its structure, activity, and regulation by post-translational modifications in the context of its cellular function. We outline open questions regarding the biology of SAMHD1 whose answers will be important for understanding its function as a regulator of cell cycle progression, genomic integrity, and in autoimmunity.
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Affiliation(s)
- Christopher H Mauney
- a Department of Biochemistry , Center for Structural Biology, Wake Forest School of Medicine , Winston Salem , NC , USA
| | - Thomas Hollis
- a Department of Biochemistry , Center for Structural Biology, Wake Forest School of Medicine , Winston Salem , NC , USA
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SAMHD1 suppresses innate immune responses to viral infections and inflammatory stimuli by inhibiting the NF-κB and interferon pathways. Proc Natl Acad Sci U S A 2018; 115:E3798-E3807. [PMID: 29610295 DOI: 10.1073/pnas.1801213115] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Sterile alpha motif and HD-domain-containing protein 1 (SAMHD1) blocks replication of retroviruses and certain DNA viruses by reducing the intracellular dNTP pool. SAMHD1 has been suggested to down-regulate IFN and inflammatory responses to viral infections, although the functions and mechanisms of SAMHD1 in modulating innate immunity remain unclear. Here, we show that SAMHD1 suppresses the innate immune responses to viral infections and inflammatory stimuli by inhibiting nuclear factor-κB (NF-κB) activation and type I interferon (IFN-I) induction. Compared with control cells, infection of SAMHD1-silenced human monocytic cells or primary macrophages with Sendai virus (SeV) or HIV-1, or treatment with inflammatory stimuli, induces significantly higher levels of NF-κB activation and IFN-I induction. Exogenous SAMHD1 expression in cells or SAMHD1 reconstitution in knockout cells suppresses NF-κB activation and IFN-I induction by SeV infection or inflammatory stimuli. Mechanistically, SAMHD1 inhibits NF-κB activation by interacting with NF-κB1/2 and reducing phosphorylation of the NF-κB inhibitory protein IκBα. SAMHD1 also interacts with the inhibitor-κB kinase ε (IKKε) and IFN regulatory factor 7 (IRF7), leading to the suppression of the IFN-I induction pathway by reducing IKKε-mediated IRF7 phosphorylation. Interactions of endogenous SAMHD1 with NF-κB and IFN-I pathway proteins were validated in human monocytic cells and primary macrophages. Comparing splenocytes from SAMHD1 knockout and heterozygous mice, we further confirmed SAMHD1-mediated suppression of NF-κB activation, suggesting an evolutionarily conserved property of SAMHD1. Our findings reveal functions of SAMHD1 in down-regulating innate immune responses to viral infections and inflammatory stimuli, highlighting the importance of SAMHD1 in modulating antiviral immunity.
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Herrmann A, Wittmann S, Thomas D, Shepard CN, Kim B, Ferreirós N, Gramberg T. The SAMHD1-mediated block of LINE-1 retroelements is regulated by phosphorylation. Mob DNA 2018; 9:11. [PMID: 29610582 PMCID: PMC5872582 DOI: 10.1186/s13100-018-0116-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 03/19/2018] [Indexed: 12/22/2022] Open
Abstract
Background The restriction factor SAMHD1 regulates intracellular nucleotide level by degrading dNTPs and blocks the replication of retroviruses and DNA viruses in non-cycling cells, like macrophages or dendritic cells. In patients, inactivating mutations in samhd1 are associated with the autoimmune disease Aicardi-Goutières Syndrome (AGS). The accumulation of intracellular nucleic acids derived from endogenous retroelements thriving in the absence of SAMHD1 has been discussed as potential trigger of the autoimmune reaction. In vitro, SAMHD1 has been found to restrict endogenous retroelements, like LINE-1 elements (L1). The mechanism, however, by which SAMHD1 blocks endogenous retroelements, is still unclear. Results Here, we show that SAMHD1 inhibits the replication of L1 and other endogenous retroelements in cycling cells. By applying GFP- and neomycin-based reporter assays we found that the anti-L1 activity of SAMHD1 is regulated by phosphorylation at threonine 592 (T592). Similar to the block of HIV, the cofactor binding site and the enzymatic active HD domain of SAMHD1 proofed to be essential for restriction of L1 elements. However, phosphorylation at T592 did not correlate with the dNTP hydrolase activity of SAMHD1 in cycling 293T cells suggesting an alternative mechanism of regulation. Interestingly, we found that SAMHD1 binds to ORF2 protein of L1 and that this interaction is regulated by T592 phosphorylation. Together with the finding that the block is also active in cycling cells, our results suggest that the SAMHD1-mediated inhibition of L1 is similar but not identical to HIV restriction. Conclusion Our findings show conclusively that SAMHD1 restricts the replication of endogenous retroelements in vitro. The results suggest that SAMHD1 is important for maintaining genome integrity and support the idea of an enhanced replication of endogenous retroelements in the absence of SAMHD1 in vivo, potentially triggering autoimmune diseases like AGS. Our analysis also contributes to the better understanding of the activities of SAMHD1 in antiviral defense and nucleotide metabolism. The finding that the phosphorylation of SAMHD1 at T592 regulates its activity against retroelements but not necessarily intracellular dNTP level suggests that the dNTP hydrolase activity might not be the only function of SAMHD1 important for its antiviral activity and for controlling autoimmunity. Electronic supplementary material The online version of this article (10.1186/s13100-018-0116-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexandra Herrmann
- 1Institute of Clinical and Molecular Virology, Friedrich-Alexander University Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - Sabine Wittmann
- 1Institute of Clinical and Molecular Virology, Friedrich-Alexander University Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - Dominique Thomas
- 2pharmazentrum frankfurt/ZAFES, Institute of Clinical Pharmacology, Goethe-University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
| | - Caitlin N Shepard
- 3Center for Drug Discovery, Department of Pediatrics, Emory Center for AIDS Research, Emory University, Children's Healthcare of Atlanta, Atlanta, GA 30322 USA
| | - Baek Kim
- 3Center for Drug Discovery, Department of Pediatrics, Emory Center for AIDS Research, Emory University, Children's Healthcare of Atlanta, Atlanta, GA 30322 USA.,4College of Pharmacy, Kyung-Hee University, Seoul, South Korea
| | - Nerea Ferreirós
- 2pharmazentrum frankfurt/ZAFES, Institute of Clinical Pharmacology, Goethe-University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
| | - Thomas Gramberg
- 1Institute of Clinical and Molecular Virology, Friedrich-Alexander University Erlangen-Nürnberg, Schlossgarten 4, 91054 Erlangen, Germany
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Bakir TM. The role of SAMHD1 expression and its relation to HIV-2 (Vpx) gene production. Saudi Pharm J 2018; 26:903-908. [PMID: 30202235 PMCID: PMC6128726 DOI: 10.1016/j.jsps.2018.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 03/10/2018] [Indexed: 11/21/2022] Open
Abstract
SAMHD1 (sterile alpha motif and HD domain 1) is a protein that is found in myeloid cells, which restricts HIV1 replication. It depletes the de-oxy-nucleoside tri-phosphate (dNTPs) pool needed for a viral cDNA synthesis leading to inhibition of viral replication inside the cells. However, it does not restrict HIV2 replication in myeloid cells due to the presence of viral Vpx protein. Vpx is a virion-associated protein which augments viral infectivity and it only exists in HIV2 and it has been recently shown in Simian Immunodeficiency Virus (SIV) and which can induce degradation of SAMHD1 protein. This increases the amount of dNTPs for viral reverse transcription in cytoplasm and HIV infection. HIV2 reverse transcription is believed to be less active than HIV1 and this could be the reason for the absence of Vpx from HIV1. Protein expression and interaction between Vpx and SAMHD1 remains unclear. The interaction of SAMHD1 and HIV2-VPx patients' cells can be considered as a first step to help in the development for more effective anti-HIV drugs and possible novel intervention therapy in the future. Present review article provides comprehensive insights on the above issue. We performed a comprehensive literature search in the bibliographic database “Pubmed,” looking at studies discussing the SAMHDI and Vpx interactions.
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Ryoo J, Hwang SY, Choi J, Oh C, Ahn K. Reply to SAMHD1-mediated HIV-1 restriction in cells does not involve ribonuclease activity. Nat Med 2018; 22:1074-1075. [PMID: 27711067 DOI: 10.1038/nm.4164] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jeongmin Ryoo
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sung-Yeon Hwang
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Jongsu Choi
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Changhoon Oh
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Kwangseog Ahn
- Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
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Raniga K, Liang C. Interferons: Reprogramming the Metabolic Network against Viral Infection. Viruses 2018; 10:E36. [PMID: 29342871 PMCID: PMC5795449 DOI: 10.3390/v10010036] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/09/2018] [Accepted: 01/12/2018] [Indexed: 12/12/2022] Open
Abstract
Viruses exploit the host and induce drastic metabolic changes to ensure an optimal environment for replication and the production of viral progenies. In response, the host has developed diverse countermeasures to sense and limit these alterations to combat viral infection. One such host mechanism is through interferon signaling. Interferons are cytokines that enhances the transcription of hundreds of interferon-stimulated genes (ISGs) whose products are key players in the innate immune response to viral infection. In addition to their direct targeting of viral components, interferons and ISGs exert profound effects on cellular metabolism. Recent studies have started to illuminate on the specific role of interferon in rewiring cellular metabolism to activate immune cells and limit viral infection. This review reflects on our current understanding of the complex networking that occurs between the virus and host at the interface of cellular metabolism, with a focus on the ISGs in particular, cholesterol-25-hydroxylase (CH25H), spermidine/spermine acetyltransferase 1 (SAT1), indoleamine-2,3-dioxygenase (IDO1) and sterile alpha motif and histidine/aspartic acid domain-containing protein 1 (SAMHD1), which were recently discovered to modulate specific metabolic events and consequently deter viral infection.
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Affiliation(s)
- Kavita Raniga
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
- Department of Microbiology & Immunology, McGill University, Montreal, QC H3A 2B4, Canada.
| | - Chen Liang
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
- Department of Microbiology & Immunology, McGill University, Montreal, QC H3A 2B4, Canada.
- Department of Medicine, McGill University, Montreal, QC H3A 2B4, Canada.
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40
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Oh C, Ryoo J, Park K, Kim B, Daly MB, Cho D, Ahn K. A central role for PI3K-AKT signaling pathway in linking SAMHD1-deficiency to the type I interferon signature. Sci Rep 2018; 8:84. [PMID: 29311560 PMCID: PMC5758801 DOI: 10.1038/s41598-017-18308-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 12/08/2017] [Indexed: 11/08/2022] Open
Abstract
The autoimmune disorder Aicardi-Goutières syndrome (AGS) is characterized by a constitutive type I interferon response. SAMHD1 possesses both dNTPase and RNase activities and mutations in SAMHD1 cause AGS; however, how SAMHD1-deficiency causes the type I interferon response in patients with AGS remains unknown. Here, we show that endogenous RNA substrates accumulated in the absence of SAMHD1 act as a major immunogenic source for the type I interferon response. Reconstitution of SAMHD1-negative human cells with wild-type but not RNase-defective SAMHD1 abolishes spontaneous type I interferon induction. We further identify that the PI3K/AKT/IRF3 signaling pathway is essential for the type I interferon response in SAMHD1-deficient human monocytic cells. Treatment of PI3K or AKT inhibitors dramatically reduces the type I interferon signatures in SAMHD1-deficient cells. Moreover, SAMHD1/AKT1 double knockout relieves the type I interferon signatures to the levels observed for wild-type cells. Identification of AGS-related RNA sensing pathway provides critical insights into the molecular pathogenesis of the type I interferonopathies such as AGS and overlapping autoimmune disorders.
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Affiliation(s)
- Changhoon Oh
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- Center for RNA Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
- Department of the Interdisciplinary Program in Genetic Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jeongmin Ryoo
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- Center for RNA Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
| | - Kiwon Park
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Baek Kim
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, 30322, USA
| | - Michele B Daly
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, 30322, USA
| | - DongYeon Cho
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- Center for RNA Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea
| | - Kwangseog Ahn
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- Center for RNA Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.
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p21 Restricts HIV-1 in Monocyte-Derived Dendritic Cells through the Reduction of Deoxynucleoside Triphosphate Biosynthesis and Regulation of SAMHD1 Antiviral Activity. J Virol 2017; 91:JVI.01324-17. [PMID: 28931685 DOI: 10.1128/jvi.01324-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/15/2017] [Indexed: 02/07/2023] Open
Abstract
HIV-1 infection of noncycling cells, such as dendritic cells (DCs), is impaired due to limited availability of deoxynucleoside triphosphates (dNTPs), which are needed for HIV-1 reverse transcription. The levels of dNTPs are tightly regulated during the cell cycle and depend on the balance between dNTP biosynthesis and degradation. SAMHD1 potently blocks HIV-1 replication in DCs, although the underlying mechanism is still unclear. SAMHD1 has been reported to be able to degrade dNTPs and viral nucleic acids, which may both hamper HIV-1 reverse transcription. The relative contribution of these activities may differ in cycling and noncycling cells. Here, we show that inhibition of HIV-1 replication in monocyte-derived DCs (MDDCs) is associated with an increased expression of p21cip1/waf, a cell cycle regulator that is involved in the differentiation and maturation of DCs. Induction of p21 in MDDCs decreases the pool of dNTPs and increases the antiviral active isoform of SAMHD1. Although both processes are complementary in inhibiting HIV-1 replication, the antiviral activity of SAMHD1 in our primary cell model appears to be, at least partially, independent of its dNTPase activity. The reduction in the pool of dNTPs in MDDCs appears rather mostly due to a p21-mediated suppression of several enzymes involved in dNTP synthesis (i.e., RNR2, TYMS, and TK-1). These results are important to better understand the interplay between HIV-1 and DCs and may inform the design of new therapeutic approaches to decrease viral dissemination and improve immune responses against HIV-1.IMPORTANCE DCs play a key role in the induction of immune responses against HIV. However, HIV has evolved ways to exploit these cells, facilitating immune evasion and virus dissemination. We have found that the expression of p21, a cyclin-dependent kinase inhibitor involved in cell cycle regulation and monocyte differentiation and maturation, potentially can contribute to the inhibition of HIV-1 replication in monocyte-derived DCs through multiple mechanisms. p21 decreased the size of the intracellular dNTP pool. In parallel, p21 prevented SAMHD1 phosphorylation and promoted SAMHD1 dNTPase-independent antiviral activity. Thus, induction of p21 resulted in conditions that allowed the effective inhibition of HIV-1 replication through complementary mechanisms. Overall, p21 appears to be a key regulator of HIV infection in myeloid cells.
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Antonucci JM, St Gelais C, Wu L. The Dynamic Interplay between HIV-1, SAMHD1, and the Innate Antiviral Response. Front Immunol 2017; 8:1541. [PMID: 29176984 PMCID: PMC5686096 DOI: 10.3389/fimmu.2017.01541] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 10/30/2017] [Indexed: 01/03/2023] Open
Abstract
The innate immune response constitutes the first cellular line of defense against initial HIV-1 infection. Immune cells sense invading virus and trigger signaling cascades that induce antiviral defenses to control or eliminate infection. Professional antigen-presenting cells located in mucosal tissues, including dendritic cells and macrophages, are critical for recognizing HIV-1 at the site of initial exposure. These cells are less permissive to HIV-1 infection compared to activated CD4+ T-cells, which is mainly due to host restriction factors that serve an immediate role in controlling the establishment or spread of viral infection. However, HIV-1 can exploit innate immune cells and their cellular factors to avoid detection and clearance by the host immune system. Sterile alpha motif and HD-domain containing protein 1 (SAMHD1) is the mammalian deoxynucleoside triphosphate triphosphohydrolase responsible for regulating intracellular dNTP pools and restricting the replication of HIV-1 in non-dividing myeloid cells and quiescent CD4+ T-cells. Here, we review and analyze the latest literature on the antiviral function of SAMHD1, including the mechanism of HIV-1 restriction and the ability of SAMHD1 to regulate the innate immune response to viral infection. We also provide an overview of the dynamic interplay between HIV-1, SAMHD1, and the cell-intrinsic antiviral response to elucidate how SAMHD1 modulates HIV-1 infection in non-dividing immune cells. A more complete understanding of SAMHD1’s role in the innate immune response to HIV-1 infection may help develop stratagems to enhance its antiviral effects and to more efficiently block HIV-1 replication and avoid the pathogenic result of viral infection.
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Affiliation(s)
- Jenna M Antonucci
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Corine St Gelais
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Li Wu
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
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Rocha-Perugini V, Suárez H, Álvarez S, López-Martín S, Lenzi GM, Vences-Catalán F, Levy S, Kim B, Muñoz-Fernández MA, Sánchez-Madrid F, Yáñez-Mó M. CD81 association with SAMHD1 enhances HIV-1 reverse transcription by increasing dNTP levels. Nat Microbiol 2017; 2:1513-1522. [PMID: 28871089 PMCID: PMC5660623 DOI: 10.1038/s41564-017-0019-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 08/01/2017] [Indexed: 12/15/2022]
Abstract
In this study, we report that the tetraspanin CD81 enhances human immunodeficiency virus (HIV)-1 reverse transcription in HIV-1-infected cells. This is enabled by the direct interaction of CD81 with the deoxynucleoside triphosphate phosphohydrolase SAMHD1. This interaction prevents endosomal accumulation and favours the proteasome-dependent degradation of SAMHD1. Consequently, CD81 depletion results in SAMHD1 increased expression, decreasing the availability of deoxynucleoside triphosphates (dNTP) and thus HIV-1 reverse transcription. Conversely, CD81 overexpression, but not the expression of a CD81 carboxy (C)-terminal deletion mutant, increases cellular dNTP content and HIV-1 reverse transcription. Our results demonstrate that the interaction of CD81 with SAMHD1 controls the metabolic rate of HIV-1 replication by tuning the availability of building blocks for reverse transcription, namely dNTPs. Together with its role in HIV-1 entry and budding into host cells, the data herein indicate that HIV-1 uses CD81 as a rheostat that controls different stages of the infection.
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Affiliation(s)
- Vera Rocha-Perugini
- Servicio de Inmunología, Hospital de la Princesa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Madrid, 28006, Spain
- Vascular Pathophysiology Research Area, Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, 28029, Spain
| | - Henar Suárez
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Centro de Biología Molecular Severo Ochoa, Madrid, 28049, Spain
| | - Susana Álvarez
- Servicio de Inmunobiología Molecular del Hospital Universitario Gregorio Marañón, Madrid, 28007, Spain
| | - Soraya López-Martín
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Centro de Biología Molecular Severo Ochoa, Madrid, 28049, Spain
| | - Gina M Lenzi
- Center for Drug Discovery, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30332, USA
| | - Felipe Vences-Catalán
- Division of Oncology, Center for Clinical Sciences Research, Stanford University, Stanford, CA, 94305-5151, USA
| | - Shoshana Levy
- Division of Oncology, Center for Clinical Sciences Research, Stanford University, Stanford, CA, 94305-5151, USA
| | - Baek Kim
- Center for Drug Discovery, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30332, USA
| | - María A Muñoz-Fernández
- Servicio de Inmunobiología Molecular del Hospital Universitario Gregorio Marañón, Madrid, 28007, Spain
| | - Francisco Sánchez-Madrid
- Servicio de Inmunología, Hospital de la Princesa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Madrid, 28006, Spain
- Vascular Pathophysiology Research Area, Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, 28029, Spain
- CIBER Cardiovascular, Madrid, Spain
| | - Maria Yáñez-Mó
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Centro de Biología Molecular Severo Ochoa, Madrid, 28049, Spain.
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Patra KK, Bhattacharya A, Bhattacharya S. Allosteric Signal Transduction in HIV-1 Restriction Factor SAMHD1 Proceeds via Reciprocal Handshake across Monomers. J Chem Inf Model 2017; 57:2523-2538. [PMID: 28956603 DOI: 10.1021/acs.jcim.7b00279] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The sterile alpha motif and histidine-aspartate domain-containing protein 1 (or SAMHD1), a human dNTP-triphosphohydrolase, contributes to HIV-1 restriction in select terminally differentiated cells of the immune system. The catalytically active form of the protein is an allosterically triggered tetramer, whose HIV-1 restriction properties are attributed to its dNTP-triphosphohydrolase activity. The tetramer itself is assembled by a GTP/dNTP combination. This enzyme uses the strategy of deoxynucleotide starvation, which is thought to prevent effective reverse transcription of the retroviral genome-hence, restricting HIV-1 propagation. HIV-2 and SIV have evolved defenses against SAMHD1, underscoring its role in restriction. Previous studies have provided high-resolution structures of GTP/dNTP-bound enzyme complexes but have not been able to provide information on dynamics. In this study, we have used correlation network analysis along with MD techniques to study the flow of allosteric information across the active complex. We have found evidence of a reciprocal allosteric "handshake" occurring across monomeric units. We have also uncovered a short linker region as the nexus for funnelling the regulatory signal from phosphorylation at T592 from the surface to the interior core of the protein.
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Affiliation(s)
- Kajwal Kumar Patra
- Department of Physics, Indian Institute of Technology Guwahati , Guwahati, Assam, India 781039
| | - Akash Bhattacharya
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio , San Antonio, Texas 78229-3900, United States
| | - Swati Bhattacharya
- Department of Physics, Indian Institute of Technology Guwahati , Guwahati, Assam, India 781039.,Department of Chemical Engineering, Indian Institute of Technology Bombay , Mumbai, India 400076
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Herold N, Rudd SG, Sanjiv K, Kutzner J, Myrberg IH, Paulin CBJ, Olsen TK, Helleday T, Henter JI, Schaller T. With me or against me: Tumor suppressor and drug resistance activities of SAMHD1. Exp Hematol 2017; 52:32-39. [PMID: 28502830 DOI: 10.1016/j.exphem.2017.05.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 04/29/2017] [Accepted: 05/02/2017] [Indexed: 01/04/2023]
Abstract
Sterile alpha motif and histidine/aspartic acid domain-containing protein 1 (SAMHD1) is a (deoxy)guanosine triphosphate (dGTP/GTP)-activated deoxyribonucleoside triphosphate (dNTP) triphosphohydrolase involved in cellular dNTP homoeostasis. Mutations in SAMHD1 have been associated with the hyperinflammatory disease Aicardi-Goutières syndrome (AGS). SAMHD1 also limits cells' permissiveness to infection with diverse viruses, including human immunodeficiency virus (HIV-1), and controls endogenous retroviruses. Increasing evidence supports the role of SAMHD1 as a tumor suppressor. However, SAMHD1 also can act as a resistance factor to nucleoside-based chemotherapies by hydrolyzing their active triphosphate metabolites, thereby reducing response of various malignancies to these anticancer drugs. Hence, informed cancer therapies must take into account the ambiguous properties of SAMHD1 as both an inhibitor of uncontrolled proliferation and a resistance factor limiting the efficacy of anticancer treatments. Here, we provide evidence that SAMHD1 is a double-edged sword for patients with acute myelogenous leukemia (AML). Our time-dependent analyses of The Cancer Genome Atlas (TCGA) AML cohort indicate that high expression of SAMHD1, even though it critically limits the efficacy of high-dose ara-C therapy, might be associated with more favorable disease progression.
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Affiliation(s)
- Nikolas Herold
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, and Karolinska University Hospital, Stockholm, Sweden; Theme of Children's and Women's Health, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.
| | - Sean G Rudd
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Kumar Sanjiv
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Juliane Kutzner
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Ida Hed Myrberg
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, and Karolinska University Hospital, Stockholm, Sweden
| | - Cynthia B J Paulin
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Thale Kristin Olsen
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, and Karolinska University Hospital, Stockholm, Sweden
| | - Thomas Helleday
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Jan-Inge Henter
- Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institutet, and Karolinska University Hospital, Stockholm, Sweden; Theme of Children's and Women's Health, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Torsten Schaller
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany.
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46
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Li M, Zhang D, Zhu M, Shen Y, Wei W, Ying S, Korner H, Li J. Roles of SAMHD1 in antiviral defense, autoimmunity and cancer. Rev Med Virol 2017; 27. [PMID: 28444859 DOI: 10.1002/rmv.1931] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 02/26/2017] [Accepted: 03/13/2017] [Indexed: 01/02/2023]
Abstract
The enzyme, sterile α motif and histidine-aspartic acid domain-containing protein 1 (SAMHD1) diminishes infection of human immunodeficiency virus type 1 (HIV-1) by hydrolyzing intracellular deoxynucleotide triphosphates (dNTPs) in myeloid cells and resting CD4+ T cells. This dNTP degradation reduces the dNTP concentration to a level insufficient for viral cDNA synthesis, thereby inhibiting retroviral replication. This antiviral enzymatic activity can be inhibited by viral protein X (Vpx). The HIV-2/SIV Vpx causes degradation of SAMHD1, thus interfering with the SAMHD1-mediated restriction of retroviral replication. Recently, SAMHD1 has been suggested to restrict HIV-1 infection by directly digesting genomic HIV-1 RNA through a still controversial RNase activity. Here, we summarize the current knowledge about structure, antiviral mechanisms, intracellular localization, interferon-regulated expression of SAMHD1. We also describe SAMHD1-deficient animal models and an antiviral drug on the basis of disrupting proteasomal degradation of SAMHD1. In addition, the possible roles of SAMHD1 in regulating innate immune sensing, Aicardi-Goutières syndrome and cancer are discussed in this review.
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Affiliation(s)
- Miaomiao Li
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui Province, PR China
| | - Dong Zhang
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui Province, PR China.,School of Basic Medical Sciences and Biopharmaceutical Research Institute, Anhui Medical University, Hefei, Anhui Province, PR China
| | - Mengying Zhu
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui Province, PR China
| | - Yuxian Shen
- School of Basic Medical Sciences and Biopharmaceutical Research Institute, Anhui Medical University, Hefei, Anhui Province, PR China
| | - Wei Wei
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Hefei, Anhui Province, PR China
| | - Songcheng Ying
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui Province, PR China.,School of Pharmacy, Anhui Medical University, Hefei, Anhui Province, PR China
| | - Heinrich Korner
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Hefei, Anhui Province, PR China.,Menzies Institute for Medical Research Tasmania, Hobart, Tasmania, Australia
| | - Jun Li
- School of Pharmacy, Anhui Medical University, Hefei, Anhui Province, PR China
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47
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Sadewasser A, Paki K, Eichelbaum K, Bogdanow B, Saenger S, Budt M, Lesch M, Hinz KP, Herrmann A, Meyer TF, Karlas A, Selbach M, Wolff T. Quantitative Proteomic Approach Identifies Vpr Binding Protein as Novel Host Factor Supporting Influenza A Virus Infections in Human Cells. Mol Cell Proteomics 2017; 16:728-742. [PMID: 28289176 DOI: 10.1074/mcp.m116.065904] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/03/2017] [Indexed: 12/24/2022] Open
Abstract
Influenza A virus (IAV) infections are a major cause for respiratory disease in humans, which affects all age groups and contributes substantially to global morbidity and mortality. IAV have a large natural host reservoir in avian species. However, many avian IAV strains lack adaptation to other hosts and hardly propagate in humans. While seasonal or pandemic IAV strains replicate efficiently in permissive human cells, many avian IAV cause abortive nonproductive infections in these hosts despite successful cell entry. However, the precise reasons for these differential outcomes are poorly defined. We hypothesized that the distinct course of an IAV infection with a given virus strain is determined by the differential interplay between specific host and viral factors. By using Spike-in SILAC mass spectrometry-based quantitative proteomics we characterized sets of cellular factors whose abundance is specifically up- or downregulated in the course of permissive versus nonpermissive IAV infection, respectively. This approach allowed for the definition and quantitative comparison of about 3500 proteins in human lung epithelial cells in response to seasonal or low-pathogenic avian H3N2 IAV. Many identified proteins were similarly regulated by both virus strains, but also 16 candidates with distinct changes in permissive versus nonpermissive infection were found. RNAi-mediated knockdown of these differentially regulated host factors identified Vpr binding protein (VprBP) as proviral host factor because its downregulation inhibited efficient propagation of seasonal IAV whereas overexpression increased viral replication of both seasonal and avian IAV. These results not only show that there are similar differences in the overall changes during permissive and nonpermissive influenza virus infections, but also provide a basis to evaluate VprBP as novel anti-IAV drug target.
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Affiliation(s)
- Anne Sadewasser
- From the ‡Unit 17 Influenza and other Respiratory Viruses", Robert Koch Institut, Seestr. 10, 13353 Berlin, Germany
| | - Katharina Paki
- From the ‡Unit 17 Influenza and other Respiratory Viruses", Robert Koch Institut, Seestr. 10, 13353 Berlin, Germany
| | - Katrin Eichelbaum
- §Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Boris Bogdanow
- §Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Sandra Saenger
- From the ‡Unit 17 Influenza and other Respiratory Viruses", Robert Koch Institut, Seestr. 10, 13353 Berlin, Germany
| | - Matthias Budt
- From the ‡Unit 17 Influenza and other Respiratory Viruses", Robert Koch Institut, Seestr. 10, 13353 Berlin, Germany
| | - Markus Lesch
- ¶Max Planck Institute for Infection Biology, Charitéplatz, 110117 Berlin, Germany
| | - Klaus-Peter Hinz
- ‖Institute of Inorganic and Analytical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Andreas Herrmann
- **Molecular Biophysics, Department of Biology, Humboldt-Universität zu Berlin, Invalidenstr. 43, 10115 Berlin, Germany
| | - Thomas F Meyer
- ¶Max Planck Institute for Infection Biology, Charitéplatz, 110117 Berlin, Germany
| | - Alexander Karlas
- ¶Max Planck Institute for Infection Biology, Charitéplatz, 110117 Berlin, Germany
| | - Matthias Selbach
- §Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Thorsten Wolff
- From the ‡Unit 17 Influenza and other Respiratory Viruses", Robert Koch Institut, Seestr. 10, 13353 Berlin, Germany;
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48
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Ordonez P, Kunzelmann S, Groom HCT, Yap MW, Weising S, Meier C, Bishop KN, Taylor IA, Stoye JP. SAMHD1 enhances nucleoside-analogue efficacy against HIV-1 in myeloid cells. Sci Rep 2017; 7:42824. [PMID: 28220857 PMCID: PMC5318888 DOI: 10.1038/srep42824] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/16/2017] [Indexed: 11/17/2022] Open
Abstract
SAMHD1 is an intracellular enzyme that specifically degrades deoxynucleoside triphosphates into component nucleoside and inorganic triphosphate. In myeloid-derived dendritic cells and macrophages as well as resting T-cells, SAMHD1 blocks HIV-1 infection through this dNTP triphosphohydrolase activity by reducing the cellular dNTP pool to a level that cannot support productive reverse transcription. We now show that, in addition to this direct effect on virus replication, manipulating cellular SAMHD1 activity can significantly enhance or decrease the anti-HIV-1 efficacy of nucleotide analogue reverse transcription inhibitors presumably as a result of modulating dNTP pools that compete for recruitment by viral polymerases. Further, a variety of other nucleotide-based analogues, not normally considered antiretrovirals, such as the anti-herpes drugs Aciclovir and Ganciclovir and the anti-cancer drug Clofarabine are now revealed as potent anti-HIV-1 agents, under conditions of low dNTPs. This in turn suggests novel uses for nucleotide analogues to inhibit HIV-1 in differentiated cells low in dNTPs.
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Affiliation(s)
- Paula Ordonez
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, London, UK
| | - Simone Kunzelmann
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Harriet C. T. Groom
- Infection and Replication of Retroviruses Laboratory, The Francis Crick Institute, London, UK
| | - Melvyn W. Yap
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, London, UK
| | - Simon Weising
- Organic Chemistry, Department of Chemistry, Faculty of Sciences, University of Hamburg, Germany
| | - Chris Meier
- Organic Chemistry, Department of Chemistry, Faculty of Sciences, University of Hamburg, Germany
| | - Kate N. Bishop
- Infection and Replication of Retroviruses Laboratory, The Francis Crick Institute, London, UK
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
| | - Jonathan P. Stoye
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, London, UK
- Faculty of Medicine, Imperial College London, London, UK
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49
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Crowl JT, Gray EE, Pestal K, Volkman HE, Stetson DB. Intracellular Nucleic Acid Detection in Autoimmunity. Annu Rev Immunol 2017; 35:313-336. [PMID: 28142323 DOI: 10.1146/annurev-immunol-051116-052331] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Protective immune responses to viral infection are initiated by innate immune sensors that survey extracellular and intracellular space for foreign nucleic acids. The existence of these sensors raises fundamental questions about self/nonself discrimination because of the abundance of self-DNA and self-RNA that occupy these same compartments. Recent advances have revealed that enzymes that metabolize or modify endogenous nucleic acids are essential for preventing inappropriate activation of the innate antiviral response. In this review, we discuss rare human diseases caused by dysregulated nucleic acid sensing, focusing primarily on intracellular sensors of nucleic acids. We summarize lessons learned from these disorders, we rationalize the existence of these diseases in the context of evolution, and we propose that this framework may also apply to a number of more common autoimmune diseases for which the underlying genetics and mechanisms are not yet fully understood.
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Affiliation(s)
- John T Crowl
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98109;
| | - Elizabeth E Gray
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98109;
| | - Kathleen Pestal
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98109;
| | - Hannah E Volkman
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98109;
| | - Daniel B Stetson
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington 98109;
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50
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Fu W, Qiu C, Zhou M, Zhu L, Yang Y, Qiu C, Zhang L, Xu X, Wang Y, Xu J, Zhang X. Immune Activation Influences SAMHD1 Expression and Vpx-mediated SAMHD1 Degradation during Chronic HIV-1 Infection. Sci Rep 2016; 6:38162. [PMID: 27922067 PMCID: PMC5138643 DOI: 10.1038/srep38162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/04/2016] [Indexed: 02/07/2023] Open
Abstract
SAMHD1 restricts human immunodeficiency virus type 1 (HIV-1) replication in myeloid cells and CD4+ T cells, while Vpx can mediate SAMHD1 degradation to promote HIV-1 replication. Although the restriction mechanisms of SAMHD1 have been well-described, SAMHD1 expression and Vpx-mediated SAMHD1 degradation during chronic HIV-1 infection were poorly understood. Flow cytometric analysis was used to directly visualize ex vivo, and after in vitro SIV-Vpx treatment, SAMHD1 expression in CD4+ T cells and monocytes. Here we report activated CD4+ T cells without SAMHD1 expression were severely reduced, and SAMHD1 in CD4+ T cells became susceptible to SIV-Vpx mediated degradation during chronic HIV-1 infection, which was absent from uninfected donors. These alterations were irreversible, even after long-term fully suppressive antiretroviral treatment. Although SAMHD1 expression in CD4+ T cells and monocytes was not found to correlate with plasma viral load, Vpx-mediated SAMHD1 degradation was associated with indicators of immune activation. In vitro assays further revealed that T-cell activation and an upregulated IFN-I pathway contributed to these altered SAMHD1 properties. These findings provide insight into how immune activation during HIV-1 infection leads to irreparable aberrations in restriction factors and in subsequent viral evasion from host antiviral defenses.
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Affiliation(s)
- Weihui Fu
- Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Chao Qiu
- Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China.,Huashan Hospital, Fudan University, Shanghai, China.,Minhang Hospital, Fudan University, Shanghai, China
| | - Mingzhe Zhou
- Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Lingyan Zhu
- Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Yu Yang
- Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Chenli Qiu
- Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Linxia Zhang
- Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Xuan Xu
- Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Ying Wang
- Shanghai Municipal Center for Disease Control &Prevention, Shanghai, China
| | - Jianqing Xu
- Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaoyan Zhang
- Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Medical Molecular Virology of Ministry of Education/Health at Shanghai Medical College, Fudan University, Shanghai, China
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