1
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Abdelrazak Morsy MH, Lilienthal I, Lord M, Merrien M, Wasik AM, Sureda-Gómez M, Amador V, Johansson HJ, Lehtiö J, Garcia-Torre B, Martin-Subero JI, Tsesmetzis N, Tao S, Schinazi RF, Kim B, Sorteberg AL, Wickström M, Sheppard D, Rassidakis GZ, Taylor IA, Christensson B, Campo E, Herold N, Sander B. SOX11 is a novel binding partner and endogenous inhibitor of SAMHD1 ara-CTPase activity in mantle cell lymphoma. Blood 2024; 143:1953-1964. [PMID: 38237141 PMCID: PMC11103171 DOI: 10.1182/blood.2023022241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/18/2023] [Accepted: 01/08/2024] [Indexed: 01/24/2024] Open
Abstract
ABSTRACT Sterile alpha motif and histidine-aspartate (HD) domain-containing protein 1 (SAMHD1) is a deoxynucleoside triphosphate triphosphohydrolase with ara-CTPase activity that confers cytarabine (ara-C) resistance in several hematological malignancies. Targeting SAMHD1's ara-CTPase activity has recently been demonstrated to enhance ara-C efficacy in acute myeloid leukemia. Here, we identify the transcription factor SRY-related HMG-box containing protein 11 (SOX11) as a novel direct binding partner and first known endogenous inhibitor of SAMHD1. SOX11 is aberrantly expressed not only in mantle cell lymphoma (MCL), but also in some Burkitt lymphomas. Coimmunoprecipitation of SOX11 followed by mass spectrometry in MCL cell lines identified SAMHD1 as the top SOX11 interaction partner, which was validated by proximity ligation assay. In vitro, SAMHD1 bound to the HMG box of SOX11 with low-micromolar affinity. In situ crosslinking studies further indicated that SOX11-SAMHD1 binding resulted in a reduced tetramerization of SAMHD1. Functionally, expression of SOX11 inhibited SAMHD1 ara-CTPase activity in a dose-dependent manner resulting in ara-C sensitization in cell lines and in a SOX11-inducible mouse model of MCL. In SOX11-negative MCL, SOX11-mediated ara-CTPase inhibition could be mimicked by adding the recently identified SAMHD1 inhibitor hydroxyurea. Taken together, our results identify SOX11 as a novel SAMHD1 interaction partner and its first known endogenous inhibitor with potentially important implications for clinical therapy stratification.
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Affiliation(s)
- Mohammad Hamdy Abdelrazak Morsy
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
- Department of Applied Medical Chemistry, Medical Research Institute, Alexandria University, Alexandria, Egypt
| | - Ingrid Lilienthal
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Martin Lord
- Department of Pharmaceutical Biosciences, Immuno-oncology, Uppsala University Biomedical Centre, Uppsala, Sweden
| | - Magali Merrien
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Agata Magdalena Wasik
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Marta Sureda-Gómez
- Institut d'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain
| | - Virginia Amador
- Institut d'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer, Madrid, Spain
| | | | - Janne Lehtiö
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
| | | | - Jose Ignacio Martin-Subero
- Institut d'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Nikolaos Tsesmetzis
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Sijia Tao
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA
| | - Raymond F. Schinazi
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA
| | - Baek Kim
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA
| | - Agnes L. Sorteberg
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Malin Wickström
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Devon Sheppard
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Georgios Z. Rassidakis
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Birger Christensson
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Elias Campo
- Institut d'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer, Madrid, Spain
- Hematopathology Section, Department of Anatomic Pathology, Hospital Clinic Barcelona, University of Barcelona, Barcelona, Spain
| | - Nikolas Herold
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
- Paediatric Oncology, Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Birgitta Sander
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
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2
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Lin C, Kuffour EO, Li T, Gertzen CGW, Kaiser J, Luedde T, König R, Gohlke H, Münk C. The ISG15-Protease USP18 Is a Pleiotropic Enhancer of HIV-1 Replication. Viruses 2024; 16:485. [PMID: 38675828 PMCID: PMC11053637 DOI: 10.3390/v16040485] [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: 02/16/2024] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 04/28/2024] Open
Abstract
The innate immune response to viruses is formed in part by interferon (IFN)-induced restriction factors, including ISG15, p21, and SAMHD1. IFN production can be blocked by the ISG15-specific protease USP18. HIV-1 has evolved to circumvent host immune surveillance. This mechanism might involve USP18. In our recent studies, we demonstrate that HIV-1 infection induces USP18, which dramatically enhances HIV-1 replication by abrogating the antiviral function of p21. USP18 downregulates p21 by accumulating misfolded dominant negative p53, which inactivates wild-type p53 transactivation, leading to the upregulation of key enzymes involved in de novo dNTP biosynthesis pathways and inactivated SAMHD1. Despite the USP18-mediated increase in HIV-1 DNA in infected cells, it is intriguing to note that the cGAS-STING-mediated sensing of the viral DNA is abrogated. Indeed, the expression of USP18 or knockout of ISG15 inhibits the sensing of HIV-1. We demonstrate that STING is ISGylated at residues K224, K236, K289, K347, K338, and K370. The inhibition of STING K289-linked ISGylation suppresses its oligomerization and IFN induction. We propose that human USP18 is a novel factor that potentially contributes in multiple ways to HIV-1 replication.
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Affiliation(s)
- Chaohui Lin
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.L.); (E.O.K.); (T.L.); (T.L.)
| | - Edmund Osei Kuffour
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.L.); (E.O.K.); (T.L.); (T.L.)
| | - Taolan Li
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.L.); (E.O.K.); (T.L.); (T.L.)
| | - Christoph G. W. Gertzen
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.G.W.G.); (J.K.); (H.G.)
| | - Jesko Kaiser
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.G.W.G.); (J.K.); (H.G.)
| | - Tom Luedde
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.L.); (E.O.K.); (T.L.); (T.L.)
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institut, 63225 Langen, Germany;
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.G.W.G.); (J.K.); (H.G.)
- Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Carsten Münk
- Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.L.); (E.O.K.); (T.L.); (T.L.)
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3
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Morsy MHA, Lilienthal I, Lord M, Merrien M, Wasik AM, Sureda-Gómez M, Amador V, Johansson HJ, Lehtiö J, Garcia-Torre B, Martin-Subero JI, Tsesmetzis N, Tao S, Schinazi RF, Kim B, Sorteberg AL, Wickström M, Sheppard D, Rassidakis GZ, Taylor IA, Christensson B, Campo E, Herold N, Sander B. SOX11 is a novel binding partner and endogenous inhibitor of SAMHD1 ara-CTPase activity in mantle cell lymphoma. Blood 2024; 143:1953-1964. [PMID: 38774451 PMCID: PMC7615944 DOI: 10.1182/blood.2023022241/2210808/blood.2023022241.pdf] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2024] Open
Abstract
The sterile alpha motif and histidine-aspartate (HD) domain containing protein 1 (SAMHD1) is a deoxynucleoside triphosphate triphosphohydrolase with ara-CTPase activity that confers cytarabine (ara-C) resistance in several haematological malignancies. Targeting SAMHD1's ara-CTPase activity has recently been demonstrated to enhance ara-C efficacy in acute myeloid leukemia. Here, we identify the transcription factor SRY-related HMG-box containing protein 11 (SOX11) as a novel direct binding partner and first known endogenous inhibitor of SAMHD1. SOX11 is aberrantly expressed not only in mantle cell lymphoma (MCL), but also in some Burkitt lymphomas. Co-immunoprecipitation of SOX11 followed by mass spectrometry in MCL cell lines identified SAMHD1 as the top SOX11 interaction partner which was validated by proximity ligation assay. In vitro, SAMHD1 bound to the HMG box of SOX11 with low-micromolar affinity. In situ crosslinking studies further indicated that SOX11-SAMHD1 binding resulted in a reduced tetramerization of SAMHD1. Functionally, expression of SOX11 inhibited SAMHD1 ara-CTPase activity in a dose-dependent manner resulting in ara-C sensitization in cell lines and in a SOX11-inducible mouse model of MCL. In SOX11-negative MCL, SOX11-mediated ara-CTPase inhibition could be mimicked by adding the recently identified SAMHD1 inhibitor hydroxyurea. Taken together, our results identify SOX11 as a novel SAMHD1 interaction partner and its first known endogenous inhibitor with potentially important implications for clinical therapy stratification.
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Affiliation(s)
- Mohammad Hamdy Abdelrazak Morsy
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet and Karolinska University Hospital, SE14186, Stockholm, Sweden
- Department of Applied Medical Chemistry, Medical Research Institute, Alexandria University, 21561, Alexandria, Egypt
| | - Ingrid Lilienthal
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Martin Lord
- Department of Pharmaceutical Biosciences, Immuno-oncology, Uppsala University Biomedical Centre (BMC), SE-751 24, Uppsala, Sweden
| | - Magali Merrien
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet and Karolinska University Hospital, SE14186, Stockholm, Sweden
| | - Agata Magdalena Wasik
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet and Karolinska University Hospital, SE14186, Stockholm, Sweden
| | - Marta Sureda-Gómez
- Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Barcelona, Spain
| | - Virginia Amador
- Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | | | - Janne Lehtiö
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Beatriz Garcia-Torre
- Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Barcelona, Spain
| | - Jose Ignacio Martin-Subero
- Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Nikolaos Tsesmetzis
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Sijia Tao
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA
| | - Raymond F Schinazi
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA
| | - Baek Kim
- Center for ViroScience and Cure, Department of Pediatrics, School of Medicine, Emory University, Atlanta, USA
| | - Agnes L Sorteberg
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Malin Wickström
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
| | - Devon Sheppard
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Georgios Z Rassidakis
- Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Birger Christensson
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet and Karolinska University Hospital, SE14186, Stockholm, Sweden
| | - Elias Campo
- Institut d'Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
- Hematopathology Section, Department of Anatomic Pathology, Hospital Clinic Barcelona, University of Barcelona, Barcelona, Spain
| | - Nikolas Herold
- Childhood Cancer Research Unit, Department of Women’s, and Children’s Health, Karolinska Institutet, Solna, Sweden
- Paediatric Oncology, Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Birgitta Sander
- Department of Laboratory Medicine, Division of Pathology, Karolinska Institutet and Karolinska University Hospital, SE14186, Stockholm, Sweden
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4
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Antequera-Parrilla P, Castillo-Acosta VM, Bosch-Navarrete C, Ruiz-Pérez LM, González-Pacanowska D. A nuclear orthologue of the dNTP triphosphohydrolase SAMHD1 controls dNTP homeostasis and genomic stability in Trypanosoma brucei. Front Cell Infect Microbiol 2023; 13:1241305. [PMID: 37674581 PMCID: PMC10478004 DOI: 10.3389/fcimb.2023.1241305] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/07/2023] [Indexed: 09/08/2023] Open
Abstract
Maintenance of dNTPs pools in Trypanosoma brucei is dependent on both biosynthetic and degradation pathways that together ensure correct cellular homeostasis throughout the cell cycle which is essential for the preservation of genomic stability. Both the salvage and de novo pathways participate in the provision of pyrimidine dNTPs while purine dNTPs are made available solely through salvage. In order to identify enzymes involved in degradation here we have characterized the role of a trypanosomal SAMHD1 orthologue denominated TbHD82. Our results show that TbHD82 is a nuclear enzyme in both procyclic and bloodstream forms of T. brucei. Knockout forms exhibit a hypermutator phenotype, cell cycle perturbations and an activation of the DNA repair response. Furthermore, dNTP quantification of TbHD82 null mutant cells revealed perturbations in nucleotide metabolism with a substantial accumulation of dATP, dCTP and dTTP. We propose that this HD domain-containing protein present in kinetoplastids plays an essential role acting as a sentinel of genomic fidelity by modulating the unnecessary and detrimental accumulation of dNTPs.
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Affiliation(s)
| | - Víctor M. Castillo-Acosta
- Instituto de Parasitología y Biomedicina “López-Neyra, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | | | | | - Dolores González-Pacanowska
- Instituto de Parasitología y Biomedicina “López-Neyra, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
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5
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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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6
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Withers SE, Rowlands CF, Tapia VS, Hedley F, Mosneag IE, Crilly S, Rice GI, Badrock AP, Hayes A, Allan SM, Briggs TA, Kasher PR. Characterization of a mutant samhd1 zebrafish model implicates dysregulation of cholesterol biosynthesis in Aicardi-Goutières syndrome. Front Immunol 2023; 14:1100967. [PMID: 36949945 PMCID: PMC10025490 DOI: 10.3389/fimmu.2023.1100967] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/20/2023] [Indexed: 03/08/2023] Open
Abstract
Aicardi-Goutières syndrome (AGS1-9) is a genetically determined encephalopathy that falls under the type I interferonopathy disease class, characterized by excessive type I interferon (IFN-I) activity, coupled with upregulation of IFN-stimulated genes (ISGs), which can be explained by the vital role these proteins play in self-non-self-discrimination. To date, few mouse models fully replicate the vast clinical phenotypes observed in AGS patients. Therefore, we investigated the use of zebrafish as an alternative species for generating a clinically relevant model of AGS. Using CRISPR-cas9 technology, we generated a stable mutant zebrafish line recapitulating AGS5, which arises from recessive mutations in SAMHD1. The resulting homozygous mutant zebrafish larvae possess a number of neurological phenotypes, exemplified by variable, but increased expression of several ISGs in the head region, a significant increase in brain cell death, microcephaly and locomotion deficits. A link between IFN-I signaling and cholesterol biosynthesis has been highlighted by others, but not previously implicated in the type I interferonopathies. Through assessment of neurovascular integrity and qPCR analysis we identified a significant dysregulation of cholesterol biosynthesis in the zebrafish model. Furthermore, dysregulation of cholesterol biosynthesis gene expression was also observed through RNA sequencing analysis of AGS patient whole blood. From this novel finding, we hypothesize that cholesterol dysregulation may play a role in AGS disease pathophysiology. Further experimentation will lend critical insight into the molecular pathophysiology of AGS and the potential links involving aberrant type I IFN signaling and cholesterol dysregulation.
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Affiliation(s)
- Sarah E. Withers
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
| | - Charlie F. Rowlands
- Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Genomic Medicine, St. Mary’s Hospital, Manchester University National Health Service (NHS) Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Victor S. Tapia
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
| | - Frances Hedley
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
| | - Ioana-Emilia Mosneag
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
| | - Siobhan Crilly
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
| | - Gillian I. Rice
- Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Genomic Medicine, St. Mary’s Hospital, Manchester University National Health Service (NHS) Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Andrew P. Badrock
- Medical Research Council (MRC) Human Genetics Unit, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew Hayes
- Genomic Technologies Core Facility, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
| | - Stuart M. Allan
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Tracy A. Briggs
- Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Genomic Medicine, St. Mary’s Hospital, Manchester University National Health Service (NHS) Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Paul R. Kasher
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
- Geoffrey Jefferson Brain Research Centre, The Manchester Academic Health Science Centre, Northern Care Alliance National Health Service (NHS) Foundation Trust, The University of Manchester, Manchester, United Kingdom
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
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7
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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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8
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Tsai KD, Lee YC, Chen BY, Wu LS, Liang SY, Liu MY, Hung YW, Hsu HL, Chen PQ, Shieh JC, Lee YJ, Lin TH. Recombinant Klotho attenuates IFNγ receptor signaling and SAMHD1 expression through blocking NF-κB translocation in glomerular mesangial cells. Int J Med Sci 2023; 20:810-817. [PMID: 37213666 PMCID: PMC10198147 DOI: 10.7150/ijms.78279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 03/30/2023] [Indexed: 05/23/2023] Open
Abstract
Interferon gamma (IFNγ) is a cytokine implicated in the pathogenesis of autoimmune diseases. SAM and HD domain-containing protein 1 (SAMHD1) is an IFNγ-inducible protein that modulates cellular dNTP levels. Mutations in the human SAMHD1 gene cause Aicardi-Goutières (AG) syndrome, an autoimmune disease sharing similar clinical features with systemic lupus erythematosus (SLE). Klotho is an anti-inflammatory protein which suppresses aging through multiple mechanisms. Implication of Klotho in autoimmune response is identified in rheumatologic diseases such as SLE. Little information exists regarding the effect of Klotho in lupus nephritis, one of the prevalent symptoms of SLE. The present study verified the effect of IFNγ on SAMHD1 and Klotho expression in MES-13 glomerular mesangial cells, a special cell type in glomerulus that is critically involved in lupus nephritis. IFNγ upregulated SAMHD1 expression in MES-13 cells through the Janus kinase-signal transducer and activator of transcription 1 (JAK-STAT1) and the nuclear factor kappa B (NFκB) signaling pathways. IFNγ decreased Klotho protein expression in MES-13 cells. Treatment of MES-13 cells with recombinant Klotho protein inhibited SAMHD1 expression by blocking IFNγ-induced NFκB nuclear translocation, but showed no effect on JAK-STAT1 signaling. Collectively, our findings support the protective role of Klotho in attenuating lupus nephritis through the inhibition of IFNγ-induced SAMHD1 expression and IFNγ downstream signaling in MES-13 cells.
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Affiliation(s)
- Kuen-Daw Tsai
- Department of Internal Medicine, China Medical University Beigang Hospital, 123 Sinde Road, Beigang Township, Yunlin County, 65152, Taiwan, ROC
- School of Chinese Medicine, College of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan, ROC
| | - Yi-Chao Lee
- Ph.D. Program in Medical Neuroscience, College of Medical Science and Technology, Taipei Medical University, Taipei, 11031, Taiwan
| | - Bo-Yu Chen
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Li-Syuan Wu
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Shan-Yuan Liang
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Ming-Yuan Liu
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Yu-Wen Hung
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Hui-Ling Hsu
- Department of Respiratory Therapy, China Medical University Beigang Hospital, 123 Sinde Road, Beigang Township, Yunlin County, 65152, Taiwan, ROC
| | - Pei-Qi Chen
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Jia-Ching Shieh
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
| | - Yi-Ju Lee
- Institute of Medicine, Chung Shan Medical University, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
- ✉ Corresponding authors: (T.-H.L.); (Y.-J.L.); Tel.: +886-4-24730022 (ext.11805) (T.-H.L.); +886-4-24730022 (ext. 12008) (Y.-J.L.)
| | - Ting-Hui Lin
- School of Biomedical Sciences, College of Medical Science and Technology, Chung Shan Medical University; Department of Medical Research, Chung Shan Medical University Hospital, 110 Jianguo North Road, Section 1, Taichung 40203, Taiwan, ROC
- ✉ Corresponding authors: (T.-H.L.); (Y.-J.L.); Tel.: +886-4-24730022 (ext.11805) (T.-H.L.); +886-4-24730022 (ext. 12008) (Y.-J.L.)
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9
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Felip E, Gutiérrez-Chamorro L, Gómez M, Garcia-Vidal E, Romeo M, Morán T, Layos L, Pérez-Roca L, Riveira-Muñoz E, Clotet B, Fernandez PL, Mesía R, Martínez-Cardús A, Ballana E, Margelí M. Modulation of DNA Damage Response by SAM and HD Domain Containing Deoxynucleoside Triphosphate Triphosphohydrolase (SAMHD1) Determines Prognosis and Treatment Efficacy in Different Solid Tumor Types. Cancers (Basel) 2022; 14:641. [PMID: 35158911 PMCID: PMC8833711 DOI: 10.3390/cancers14030641] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 12/31/2022] Open
Abstract
SAMHD1 is a deoxynucleotide triphosphate (dNTP) triphosphohydrolase with important roles in the control of cell proliferation and apoptosis, either through the regulation of intracellular dNTPs levels or the modulation of the DNA damage response. However, SAMHD1's role in cancer evolution is still unknown. We performed the first in-depth study of SAMHD1's role in advanced solid tumors, by analyzing samples of 128 patients treated with chemotherapy agents based on platinum derivatives and/or antimetabolites, developing novel in vitro knock-out models to explore the mechanisms driving SAMHD1 function in cancer. Low (or no) expression of SAMHD1 was associated with a positive prognosis in breast, ovarian, and non-small cell lung cancer (NSCLC) cancer patients. A predictive value was associated with low-SAMHD1 expression in NSCLC and ovarian patients treated with antimetabolites in combination with platinum derivatives. In vitro, SAMHD1 knock-out cells showed increased γ-H2AX and apoptosis, suggesting that SAMHD1 depletion induces DNA damage leading to cell death. In vitro treatment with platinum-derived drugs significantly enhanced γ-H2AX and apoptotic markers expression in knock-out cells, indicating a synergic effect of SAMHD1 depletion and platinum-based treatment. SAMHD1 expression represents a new strong prognostic and predictive biomarker in solid tumors and, thus, modulation of the SAMHD1 function may constitute a promising target for the improvement of cancer therapy.
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Affiliation(s)
- Eudald Felip
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Lucía Gutiérrez-Chamorro
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
| | - Maica Gómez
- Department of Pathology, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (M.G.); (P.L.F.)
| | - Edurne Garcia-Vidal
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
| | - Margarita Romeo
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Teresa Morán
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Laura Layos
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Laia Pérez-Roca
- Banc de Tumors, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain;
| | - Eva Riveira-Muñoz
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
| | - Bonaventura Clotet
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
| | - Pedro Luis Fernandez
- Department of Pathology, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (M.G.); (P.L.F.)
| | - Ricard Mesía
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Anna Martínez-Cardús
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Ester Ballana
- AIDS Research Institute-IrsiCaixa, IGTP (Health Research Institute Germans Trias i Pujol), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain; (E.F.); (L.G.-C.); (E.G.-V.); (E.R.-M.); (B.C.)
| | - Mireia Margelí
- Medical Oncology Department, Catalan Institute of Oncology-Badalona, Hospital Germans Trias i Pujol (HGTiP), 08916 Badalona, Spain; (M.R.); (T.M.); (L.L.); (R.M.); (A.M.-C.)
- (B-ARGO) Badalona Applied Research Group in Oncology, (IGTP), Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, Departament de Medicina, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
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10
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Banchenko S, Krupp F, Gotthold C, Bürger J, Graziadei A, O’Reilly FJ, Sinn L, Ruda O, Rappsilber J, Spahn CMT, Mielke T, Taylor IA, Schwefel D. Structural insights into Cullin4-RING ubiquitin ligase remodelling by Vpr from simian immunodeficiency viruses. PLoS Pathog 2021; 17:e1009775. [PMID: 34339457 PMCID: PMC8360603 DOI: 10.1371/journal.ppat.1009775] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/12/2021] [Accepted: 07/02/2021] [Indexed: 12/21/2022] Open
Abstract
Viruses have evolved means to manipulate the host's ubiquitin-proteasome system, in order to down-regulate antiviral host factors. The Vpx/Vpr family of lentiviral accessory proteins usurp the substrate receptor DCAF1 of host Cullin4-RING ligases (CRL4), a family of modular ubiquitin ligases involved in DNA replication, DNA repair and cell cycle regulation. CRL4DCAF1 specificity modulation by Vpx and Vpr from certain simian immunodeficiency viruses (SIV) leads to recruitment, poly-ubiquitylation and subsequent proteasomal degradation of the host restriction factor SAMHD1, resulting in enhanced virus replication in differentiated cells. To unravel the mechanism of SIV Vpr-induced SAMHD1 ubiquitylation, we conducted integrative biochemical and structural analyses of the Vpr protein from SIVs infecting Cercopithecus cephus (SIVmus). X-ray crystallography reveals commonalities between SIVmus Vpr and other members of the Vpx/Vpr family with regard to DCAF1 interaction, while cryo-electron microscopy and cross-linking mass spectrometry highlight a divergent molecular mechanism of SAMHD1 recruitment. In addition, these studies demonstrate how SIVmus Vpr exploits the dynamic architecture of the multi-subunit CRL4DCAF1 assembly to optimise SAMHD1 ubiquitylation. Together, the present work provides detailed molecular insight into variability and species-specificity of the evolutionary arms race between host SAMHD1 restriction and lentiviral counteraction through Vpx/Vpr proteins.
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Affiliation(s)
- Sofia Banchenko
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Ferdinand Krupp
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Christine Gotthold
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Jörg Bürger
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
- Microscopy and Cryo-Electron Microscopy Service Group, Max-Planck-Institute for Molecular Genetics, Berlin, Germany
| | - Andrea Graziadei
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Francis J. O’Reilly
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Ludwig Sinn
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Olga Ruda
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Juri Rappsilber
- Bioanalytics Unit, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Christian M. T. Spahn
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Thorsten Mielke
- Microscopy and Cryo-Electron Microscopy Service Group, Max-Planck-Institute for Molecular Genetics, Berlin, Germany
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - David Schwefel
- Charité–Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
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11
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Martinat C, Cormier A, Tobaly-Tapiero J, Palmic N, Casartelli N, Mahboubi B, Coggins SA, Buchrieser J, Persaud M, Diaz-Griffero F, Espert L, Bossis G, Lesage P, Schwartz O, Kim B, Margottin-Goguet F, Saïb A, Zamborlini A. SUMOylation of SAMHD1 at Lysine 595 is required for HIV-1 restriction in non-cycling cells. Nat Commun 2021; 12:4582. [PMID: 34321470 PMCID: PMC8319325 DOI: 10.1038/s41467-021-24802-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 07/05/2021] [Indexed: 02/06/2023] Open
Abstract
SAMHD1 is a cellular triphosphohydrolase (dNTPase) proposed to inhibit HIV-1 reverse transcription in non-cycling immune cells by limiting the supply of the dNTP substrates. Yet, phosphorylation of T592 downregulates SAMHD1 antiviral activity, but not its dNTPase function, implying that additional mechanisms contribute to viral restriction. Here, we show that SAMHD1 is SUMOylated on residue K595, a modification that relies on the presence of a proximal SUMO-interacting motif (SIM). Loss of K595 SUMOylation suppresses the restriction activity of SAMHD1, even in the context of the constitutively active phospho-ablative T592A mutant but has no impact on dNTP depletion. Conversely, the artificial fusion of SUMO2 to a non-SUMOylatable inactive SAMHD1 variant restores its antiviral function, a phenotype that is reversed by the phosphomimetic T592E mutation. Collectively, our observations clearly establish that lack of T592 phosphorylation cannot fully account for the restriction activity of SAMHD1. We find that SUMOylation of K595 is required to stimulate a dNTPase-independent antiviral activity in non-cycling immune cells, an effect that is antagonized by cyclin/CDK-dependent phosphorylation of T592 in cycling cells.
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Affiliation(s)
- Charlotte Martinat
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Arthur Cormier
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Joëlle Tobaly-Tapiero
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Noé Palmic
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Nicoletta Casartelli
- grid.428999.70000 0001 2353 6535Institut Pasteur, Virus and Immunity Unit, CNRS-UMR3569, Paris, France ,grid.511001.4Vaccine Research Institute, Créteil, France
| | - Bijan Mahboubi
- grid.189967.80000 0001 0941 6502Emory School of Medicine, Atlanta, USA
| | - Si’Ana A. Coggins
- grid.189967.80000 0001 0941 6502Emory School of Medicine, Atlanta, USA
| | - Julian Buchrieser
- grid.428999.70000 0001 2353 6535Institut Pasteur, Virus and Immunity Unit, CNRS-UMR3569, Paris, France ,grid.511001.4Vaccine Research Institute, Créteil, France ,grid.4991.50000 0004 1936 8948James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Mirjana Persaud
- grid.251993.50000000121791997Albert Einstein College of Medicine, Microbiology and Immunology, Bronx, NY USA
| | - Felipe Diaz-Griffero
- grid.251993.50000000121791997Albert Einstein College of Medicine, Microbiology and Immunology, Bronx, NY USA
| | - Lucile Espert
- grid.503217.2IRIM, University of Montpellier, UMR 9004 CNRS, Montpellier, France
| | - Guillaume Bossis
- grid.429192.50000 0004 0599 0285IGMM, Univ Montpellier, CNRS, Montpellier, France
| | - Pascale Lesage
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Olivier Schwartz
- grid.428999.70000 0001 2353 6535Institut Pasteur, Virus and Immunity Unit, CNRS-UMR3569, Paris, France ,grid.511001.4Vaccine Research Institute, Créteil, France
| | - Baek Kim
- grid.189967.80000 0001 0941 6502Emory School of Medicine, Atlanta, USA
| | | | - Ali Saïb
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France
| | - Alessia Zamborlini
- INSERM U944, CNRS UMR 7212, Genomes & Cell Biology of Disease Unit, Institut de Recherche Saint-Louis, Université de Paris, Hôpital Saint-Louis, Paris, France ,grid.457334.2Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
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12
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Bühler MM, Lu J, Scheinost S, Nadeu F, Roos-Weil D, Hensel M, Thavayogarajah T, Moch H, Manz MG, Haralambieva E, Marques Maggio E, Beà S, Giné E, Campo E, Bernard OA, Huber W, Zenz T. SAMHD1 mutations in mantle cell lymphoma are recurrent and confer in vitro resistance to nucleoside analogues. Leuk Res 2021; 107:106608. [PMID: 33979727 DOI: 10.1016/j.leukres.2021.106608] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/19/2021] [Accepted: 04/29/2021] [Indexed: 12/17/2022]
Affiliation(s)
- Marco M Bühler
- Department of Pathology and Molecular Pathology, University Hospital and University of Zurich, Zurich, Switzerland; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Hematopathology Section, Laboratory of Pathology, Hospital Clínic de Barcelona, University of Barcelona, Barcelona, Spain
| | - Junyan Lu
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Sebastian Scheinost
- Molecular Therapy in Hematology and Oncology, National Center for Tumor Diseases, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ferran Nadeu
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Cancer (CIBERONC), Madrid, Spain
| | - Damien Roos-Weil
- Gustave Roussy, INSERM U1170, Villejuif and Université Paris-Saclay Orsay, France
| | | | - Tharshika Thavayogarajah
- Department of Medical Oncology and Hematology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Holger Moch
- Department of Pathology and Molecular Pathology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Markus G Manz
- Department of Medical Oncology and Hematology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Eugenia Haralambieva
- Department of Pathology and Molecular Pathology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Ewerton Marques Maggio
- Department of Pathology and Molecular Pathology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Sílvia Beà
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Hematopathology Section, Laboratory of Pathology, Hospital Clínic de Barcelona, University of Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Cancer (CIBERONC), Madrid, Spain
| | - Eva Giné
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Cancer (CIBERONC), Madrid, Spain; Department of Hematology, Hospital Clínic de Barcelona, University of Barcelona, Barcelona, Spain
| | - Elías Campo
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Hematopathology Section, Laboratory of Pathology, Hospital Clínic de Barcelona, University of Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Cancer (CIBERONC), Madrid, Spain
| | - Olivier A Bernard
- Gustave Roussy, INSERM U1170, Villejuif and Université Paris-Saclay Orsay, France
| | - Wolfgang Huber
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany; Molecular Medicine Partnership Unit (MMPU), Heidelberg, Germany
| | - Thorsten Zenz
- Department of Medical Oncology and Hematology, University Hospital and University of Zurich, Zurich, Switzerland.
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13
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Coggins SA, Kim DH, Schinazi RF, Desrosier RC, Kim B. Enhanced enzyme kinetics of reverse transcriptase variants cloned from animals infected with SIVmac239 lacking viral protein X. J Biol Chem 2020; 295:16975-16986. [PMID: 33008888 PMCID: PMC7863885 DOI: 10.1074/jbc.ra120.015273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/01/2020] [Indexed: 12/14/2022] Open
Abstract
HIV Type 1 (HIV-1) and simian immunodeficiency virus (SIV) display differential replication kinetics in macrophages. This is because high expression levels of the active host deoxynucleotide triphosphohydrolase sterile α motif domain and histidine-aspartate domain-containing protein 1 (SAMHD1) deplete intracellular dNTPs, which restrict HIV-1 reverse transcription, and result in a restrictive infection in this myeloid cell type. Some SIVs overcome SAMHD1 restriction using viral protein X (Vpx), a viral accessory protein that induces proteasomal degradation of SAMHD1, increasing cellular dNTP concentrations and enabling efficient proviral DNA synthesis. We previously reported that SAMHD1-noncounteracting lentiviruses may have evolved to harbor RT proteins that efficiently polymerize DNA, even at low dNTP concentrations, to circumvent SAMHD1 restriction. Here we investigated whether RTs from SIVmac239 virus lacking a Vpx protein evolve during in vivo infection to more efficiently synthesize DNA at the low dNTP concentrations found in macrophages. Sequence analysis of RTs cloned from Vpx (+) and Vpx (-) SIVmac239-infected animals revealed that Vpx (-) RTs contained more extensive mutations than Vpx (+) RTs. Although the amino acid substitutions were dispersed indiscriminately across the protein, steady-state and pre-steady-state analysis demonstrated that selected SIVmac239 Vpx (-) RTs are characterized by higher catalytic efficiency and incorporation efficiency values than RTs cloned from SIVmac239 Vpx (+) infections. Overall, this study supports the possibility that the loss of Vpx may generate in vivo SIVmac239 RT variants that can counteract the limited availability of dNTP substrate in macrophages.
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Affiliation(s)
- Si'Ana A Coggins
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Dong-Hyun Kim
- Department of Pharmacy, Kyung-Hee University, Seoul, South Korea
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Ronald C Desrosier
- Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA; Children's Healthcare of Atlanta, Atlanta, Georgia, USA.
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14
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Coggins SA, Mahboubi B, Schinazi RF, Kim B. Mechanistic cross-talk between DNA/RNA polymerase enzyme kinetics and nucleotide substrate availability in cells: Implications for polymerase inhibitor discovery. J Biol Chem 2020; 295:13432-13443. [PMID: 32737197 PMCID: PMC7521635 DOI: 10.1074/jbc.rev120.013746] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/31/2020] [Indexed: 01/01/2023] Open
Abstract
Enzyme kinetic analysis reveals a dynamic relationship between enzymes and their substrates. Overall enzyme activity can be controlled by both protein expression and various cellular regulatory systems. Interestingly, the availability and concentrations of intracellular substrates can constantly change, depending on conditions and cell types. Here, we review previously reported enzyme kinetic parameters of cellular and viral DNA and RNA polymerases with respect to cellular levels of their nucleotide substrates. This broad perspective exposes a remarkable co-evolution scenario of DNA polymerase enzyme kinetics with dNTP levels that can vastly change, depending on cell proliferation profiles. Similarly, RNA polymerases display much higher Km values than DNA polymerases, possibly due to millimolar range rNTP concentrations found in cells (compared with micromolar range dNTP levels). Polymerases are commonly targeted by nucleotide analog inhibitors for the treatments of various human diseases, such as cancers and viral pathogens. Because these inhibitors compete against natural cellular nucleotides, the efficacy of each inhibitor can be affected by varying cellular nucleotide levels in their target cells. Overall, both kinetic discrepancy between DNA and RNA polymerases and cellular concentration discrepancy between dNTPs and rNTPs present pharmacological and mechanistic considerations for therapeutic discovery.
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Affiliation(s)
- Si'Ana A Coggins
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Bijan Mahboubi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA; Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, Georgia, USA.
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15
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Ferreira IATM, Porterfield JZ, Gupta RK, Mlcochova P. Cell Cycle Regulation in Macrophages and Susceptibility to HIV-1. Viruses 2020; 12:v12080839. [PMID: 32751972 PMCID: PMC7472357 DOI: 10.3390/v12080839] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/24/2020] [Accepted: 07/28/2020] [Indexed: 02/07/2023] Open
Abstract
Macrophages are the first line of defence against invading pathogens. They play a crucial role in immunity but also in regeneration and homeostasis. Their remarkable plasticity in their phenotypes and function provides them with the ability to quickly respond to environmental changes and infection. Recent work shows that macrophages undergo cell cycle transition from a G0/terminally differentiated state to a G1 state. This G0-to-G1 transition presents a window of opportunity for HIV-1 infection. Macrophages are an important target for HIV-1 but express high levels of the deoxynucleotide-triphosphate hydrolase SAMHD1, which restricts viral DNA synthesis by decreasing levels of dNTPs. While the G0 state is non-permissive to HIV-1 infection, a G1 state is very permissive to HIV-1 infection. This is because macrophages in a G1 state switch off the antiviral restriction factor SAMHD1 by phosphorylation, thereby allowing productive HIV-1 infection. Here, we explore the macrophage cell cycle and the interplay between its regulation and permissivity to HIV-1 infection.
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Affiliation(s)
- Isabella A. T. M. Ferreira
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Cambridge CB20AW, UK; (I.A.T.M.F.); (R.K.G.)
- Department of Medicine, University of Cambridge, Cambridge CB20QQ, UK
| | - J. Zachary Porterfield
- Department of Microbiology, University of Kentucky, Lexington, KY 40536, USA;
- Africa Health Research Institute, Durban 4001, South Africa
| | - Ravindra K. Gupta
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Cambridge CB20AW, UK; (I.A.T.M.F.); (R.K.G.)
- Department of Medicine, University of Cambridge, Cambridge CB20QQ, UK
- Africa Health Research Institute, Durban 4001, South Africa
| | - Petra Mlcochova
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Cambridge CB20AW, UK; (I.A.T.M.F.); (R.K.G.)
- Department of Medicine, University of Cambridge, Cambridge CB20QQ, UK
- Correspondence:
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16
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Davenne T, Klintman J, Sharma S, Rigby RE, Blest HTW, Cursi C, Bridgeman A, Dadonaite B, De Keersmaecker K, Hillmen P, Chabes A, Schuh A, Rehwinkel J. SAMHD1 Limits the Efficacy of Forodesine in Leukemia by Protecting Cells against the Cytotoxicity of dGTP. Cell Rep 2020; 31:107640. [PMID: 32402273 PMCID: PMC7225753 DOI: 10.1016/j.celrep.2020.107640] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 03/12/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022] Open
Abstract
The anti-leukemia agent forodesine causes cytotoxic overload of intracellular deoxyguanosine triphosphate (dGTP) but is efficacious only in a subset of patients. We report that SAMHD1, a phosphohydrolase degrading deoxyribonucleoside triphosphate (dNTP), protects cells against the effects of dNTP imbalances. SAMHD1-deficient cells induce intrinsic apoptosis upon provision of deoxyribonucleosides, particularly deoxyguanosine (dG). Moreover, dG and forodesine act synergistically to kill cells lacking SAMHD1. Using mass cytometry, we find that these compounds kill SAMHD1-deficient malignant cells in patients with chronic lymphocytic leukemia (CLL). Normal cells and CLL cells from patients without SAMHD1 mutation are unaffected. We therefore propose to use forodesine as a precision medicine for leukemia, stratifying patients by SAMHD1 genotype or expression.
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Affiliation(s)
- Tamara Davenne
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK; Laboratory for Disease Mechanisms in Cancer, Department of Oncology, KU Leuven and Leuven Cancer Institute (LKI), Herestraat 49, 3000 Leuven, Belgium
| | - Jenny Klintman
- Molecular Diagnostic Centre, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Sushma Sharma
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, 901 87 Umeå, Sweden
| | - Rachel E Rigby
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Henry T W Blest
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Chiara Cursi
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Anne Bridgeman
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Bernadeta Dadonaite
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Kim De Keersmaecker
- Laboratory for Disease Mechanisms in Cancer, Department of Oncology, KU Leuven and Leuven Cancer Institute (LKI), Herestraat 49, 3000 Leuven, Belgium
| | - Peter Hillmen
- St James' Institute of Oncology, St James' University Hospital, Leeds LS9 7TF, UK
| | - Andrei Chabes
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, 901 87 Umeå, Sweden
| | - Anna Schuh
- Molecular Diagnostic Centre, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK; Department of Oncology, Old Road Campus Research Building, University of Oxford, Oxford OX3 7DQ, UK; Department of Haematology, Oxford University Hospitals NHS Trust, Oxford OX3 7JL, UK
| | - Jan Rehwinkel
- Medical Research Council Human Immunology Unit, Medical Research Council Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, UK.
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17
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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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18
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Martín-Moreno A, Muñoz-Fernández MA. Dendritic Cells, the Double Agent in the War Against HIV-1. Front Immunol 2019; 10:2485. [PMID: 31708924 PMCID: PMC6820366 DOI: 10.3389/fimmu.2019.02485] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/04/2019] [Indexed: 12/19/2022] Open
Abstract
Human Immunodeficiency Virus (HIV) infects cells from the immune system and has thus developed tools to circumvent the host immunity and use it in its advance. Dendritic cells (DCs) are the first immune cells to encounter the HIV, and being the main antigen (Ag) presenting cells, they link the innate and the adaptive immune responses. While DCs work to promote an efficient immune response and halt the infection, HIV-1 has ways to take advantage of their role and uses DCs to gain faster and more efficient access to CD4+ T cells. Due to their ability to activate a specific immune response, DCs are promising candidates to achieve the functional cure of HIV-1 infection, but knowing the molecular partakers that determine the relationship between virus and cell is the key for the rational and successful design of a DC-based therapy. In this review, we summarize the current state of knowledge on how both DC subsets (myeloid and plasmacytoid DCs) act in presence of HIV-1, and focus on different pathways that the virus can take after binding to DC. First, we explore the consequences of HIV-1 recognition by each receptor on DCs, including CD4 and DC-SIGN. Second, we look at cellular mechanisms that prevent productive infection and weapons that turn cellular defense into a Trojan horse that hides the virus all the way to T cell. Finally, we discuss the possible outcomes of DC-T cell contact.
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Affiliation(s)
- Alba Martín-Moreno
- Sección de Inmunología, Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón (HGUGM), Madrid, Spain.,Instituto Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
| | - Mª Angeles Muñoz-Fernández
- Sección de Inmunología, Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón (HGUGM), Madrid, Spain.,Instituto Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Spanish HIV-HGM BioBank, Madrid, Spain.,Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER BBN), Madrid, Spain
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19
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Interferon γ and α Have Differential Effects on SAMHD1, a Potent Antiviral Protein, in Feline Lymphocytes. Viruses 2019; 11:v11100921. [PMID: 31600877 PMCID: PMC6832628 DOI: 10.3390/v11100921] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/05/2019] [Accepted: 10/06/2019] [Indexed: 12/15/2022] Open
Abstract
Sterile alpha motif and histidine/aspartic domain-containing protein 1 (SAMHD1) is a protein with anti-viral, anti-neoplastic, and anti-inflammatory properties. By degrading cellular dNTPs to constituent deoxynucleoside and free triphosphate, SAMHD1 limits viral DNA synthesis and prevents replication of HIV-1 and some DNA viruses such as HBV, vaccinia, and HSV-1. Recent findings suggest SAMHD1 is broadly active against retroviruses in addition to HIV-1, such as HIV-2, FIV, BIV, and EIAV. Interferons are cytokines produced by lymphocytes and other cells that induce a wide array of antiviral proteins, including some with activity again lentiviruses. Here we evaluated the role of IFNs on SAMHD1 gene expression, transcription, and post-translational modification in a feline CD4+ T cell line (FeTJ) and in primary feline CD4+ T lymphocytes. SAMHD1 mRNA in FetJ cells increased in a dose-related manner in response to IFNγ treatment concurrent with increased nuclear localization and phosphorylation. IFNα treatment induced SAMHD1 mRNA but did not significantly alter SAMHD1 protein detection, phosphorylation, or nuclear translocation. In purified primary feline CD4+ lymphocytes, IL2 supplementation increased SAMHD1 expression, but the addition of IFNγ did not further alter SAMHD1 protein expression or nuclear localization. Thus, the effect of IFNγ on SAMHD1 expression is cell-type dependent, with increased translocation to the nucleus and phosphorylation in FeTJ but not primary CD4+ lymphocytes. These findings imply that while SAMH1 is inducible by IFNγ, overall activity is cell type and compartment specific, which is likely relevant to the establishment of lentiviral reservoirs in quiescent lymphocyte populations.
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20
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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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21
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Jiang H, Li C, Liu Z. Expression and Relationship of SAMHD1 with Other Apoptotic and Autophagic Genes in Acute Myeloid Leukemia Patients. Acta Haematol 2019; 143:51-59. [PMID: 31434075 DOI: 10.1159/000500822] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/08/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND SAM domain- and HD domain-containing protein 1 (SAMHD1) is a cellular enzyme which is responsible for blocking replication in viruses and participates in the progression of many cancers. OBJECTIVE The aim of this study was to correlate the expression level of SAMHD1 with other apoptotic and autophagic genes in acute myeloid leukemia (AML) patients. METHODS In the present study, mRNA levels of SAMHD1 with other apoptotic and autophagic-related genes were evaluated in patients who were newly diagnosed with AML. RESULTS SAMHD1, Bcl-xl, Bax, Bak, XIAP, and cIAP1 were downregulated in the AML group compared to the non-AML group (p < 0.05). SAMHD1 expression did not correlate with the other genes, while most apoptotic genes were positively correlated with each other. SAMHD1 expression was not associated with the blood routine or blast percentage of the AML patients, while Bax, Bak, cIAP2, and LC3 were significantly correlated with white blood cells. No statistically significant differences were found between the studied genes and prognosis stratifications, but Bcl-xl, Bak, cIAP1, and Mcl-1, LC3 were expressed at lower levels in the unfavorable AML group compared to the controls. CONCLUSION SAMHD1 and Bcl-xl, Bax, Bak, XIAP, and cIAP1 were downregulated in AML patients, while there were no significant differences in the clinical characteristics and prognosis with reference to SAMHD1 expression.
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Affiliation(s)
- Huinan Jiang
- Hematology Department, Shengjing Hospital, China Medical University, Shenyang, China
| | - Chuan Li
- Hematology Department, Shengjing Hospital, China Medical University, Shenyang, China
| | - Zhuogang Liu
- Hematology Department, Shengjing Hospital, China Medical University, Shenyang, China
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22
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Increased SAMHD1 transcript expression correlates with interferon-related genes in HIV-1-infected patients. Med Microbiol Immunol 2018; 208:679-691. [PMID: 30564919 DOI: 10.1007/s00430-018-0574-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 11/24/2018] [Indexed: 01/12/2023]
Abstract
PURPOSE To investigate the contribution of SAMHD1 to HIV-1 infection in vivo and its relationship with IFN response, the expression of SAMHD1 and IFN-related pathways was evaluated in HIV-1-infected patients. METHODS Peripheral blood mononuclear cells (PBMC) from 388 HIV-1-infected patients, both therapy naïve (n = 92) and long-term HAART treated (n = 296), and from 100 gender and age-matched healthy individuals were examined. CD4+ T cells, CD14+ monocytes and gut biopsies were also analyzed in HIV-1-infected subjects on suppressive antiretroviral therapy. Gene expression levels of SAMDH1, ISGs (MxA, MxB, HERC5, IRF7) and IRF3 were evaluated by real-time RT-PCR assays. RESULTS SAMHD1 levels in HIV-1-positive patients were significantly increased compared to those in healthy donors. SAMHD1 expression was enhanced in treated patients compared to naïve patients (p < 0.0001) and healthy donors (p = 0.0038). Virologically suppressed treated patients exhibited higher SAMHD1 levels than healthy donors (p = 0.0008), viraemic patients (p = 0.0001) and naïve patients (p < 0.0001). SAMHD1 levels were also increased in CD4+ T cells compared to those in CD14+ monocytes and in PBMC compared to those of GALT. Moreover, SAMHD1 was expressed more strongly than ISGs in HIV-1-infected patients and positive correlations were found between SAMHD1, ISGs and IRF3 levels. CONCLUSIONS SAMHD1 is more strongly expressed than the classical IFN-related genes, increased during antiretroviral therapy and correlated with ISGs and IRF3 in HIV-1-infected patients.
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Mauney CH, Perrino FW, Hollis T. Identification of Inhibitors of the dNTP Triphosphohydrolase SAMHD1 Using a Novel and Direct High-Throughput Assay. Biochemistry 2018; 57:6624-6636. [PMID: 30380297 DOI: 10.1021/acs.biochem.8b01038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dNTP triphosphohydrolase SAMHD1 is a regulator of cellular dNTP pools. Given its central role in nucleotide metabolism, SAMHD1 performs important functions in cellular homeostasis, cell cycle regulation, and innate immunity. It therefore represents a high-profile target for small molecule drug design. SAMHD1 has a complex mechanism of catalytic activation that makes the design of an activating compound challenging. However, an inhibitor of SAMHD1 could serve multiple therapeutic roles, including the potentiation of antiviral and anticancer drug regimens. The lack of high-throughput screens that directly measure SAMHD1 catalytic activity has impeded efforts to identify inhibitors of SAMHD1. Here we describe a novel high-throughput screen that directly measures SAMHD1 catalytic activity. This assay results in a colorimetric end point that can be read spectrophotometrically and utilizes bis(4-nitrophenyl) phosphate as the substrate and Mn2+ as the activating cation that facilitates catalysis. When used to screen a library of Food and Drug Administration-approved drugs, this HTS identified multiple novel compounds that inhibited SAMHD1 dNTPase activity at micromolar concentrations.
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Affiliation(s)
- Christopher H Mauney
- Center for Structural Biology, Department of Biochemistry , Wake Forest School of Medicine , Winston-Salem , North Carolina 27157 , United States
| | - Fred W Perrino
- Center for Structural Biology, Department of Biochemistry , Wake Forest School of Medicine , Winston-Salem , North Carolina 27157 , United States
| | - Thomas Hollis
- Center for Structural Biology, Department of Biochemistry , Wake Forest School of Medicine , Winston-Salem , North Carolina 27157 , United States
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24
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Mahboubi B, Gavegnano C, Kim DH, Schinazi RF, Kim B. Host SAMHD1 protein restricts endogenous reverse transcription of HIV-1 in nondividing macrophages. Retrovirology 2018; 15:69. [PMID: 30316304 PMCID: PMC6186296 DOI: 10.1186/s12977-018-0452-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/06/2018] [Indexed: 12/13/2022] Open
Abstract
Background SAM domain and HD domain containing protein 1 (SAMHD1) is a host anti-HIV-1 restriction factor known to suppress viral reverse transcription in nondividing myeloid cells by its dNTP triphosphorylase activity that depletes cellular dNTPs. However, HIV-2 and some SIV strains rapidly replicate in macrophages due to their accessory protein, viral protein X (Vpx), which proteosomally degrades SAMHD1 and elevates dNTP levels. Endogenous reverse transcription (ERT) of retroviruses is the extra-cellular reverse transcription step that partially synthesizes proviral DNAs within cell-free viral particles before the viruses infect new cells. ERT activity utilizes dNTPs co-packaged during budding from the virus-producing cells, and high ERT activity is known to enhance HIV-1 infectivity in nondividing cells. Here, since Vpx elevates cellular dNTP levels in macrophages, we hypothesize that HIV-2 should contain higher ERT activity than HIV-1 in macrophages, and that the Vpx-mediated dNTP elevation should enhance both ERT activity and infectivity of HIV-1 particles produced in macrophages. Results Here, we demonstrate that HIV-2 produced from human primary monocyte derived macrophages displays higher ERT activity than HIV-1 produced from macrophages. Also, HIV-1 particles produced from macrophages treated with virus like particles (VLPs) containing Vpx, Vpx (+), displayed large increases of ERT activity with the enhanced copy numbers of early, middle and late reverse transcription products within the viral particles, compared to the viruses produced from macrophages treated with Vpx (−) VLPs. Furthermore, upon the infection with an equal p24 amount to fresh macrophages, the viruses produced from the Vpx (+) VLP treated macrophages demonstrated higher infectivity than the viruses from the Vpx (−) VLP treated macrophages. Conclusions This finding identifies the viral ERT step as an additional step of HIV-1 replication cycle that SAMHD1 restricts in nondividing myeloid target cells. Electronic supplementary material The online version of this article (10.1186/s12977-018-0452-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bijan Mahboubi
- Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Christina Gavegnano
- Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Dong-Hyun Kim
- School of Pharmacy, Kyung-Hee University, Seoul, South Korea
| | - Raymond F Schinazi
- Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Baek Kim
- Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA. .,School of Pharmacy, Kyung-Hee University, Seoul, South Korea. .,Children's Healthcare of Atlanta, Atlanta, GA, USA.
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25
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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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26
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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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27
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Chase AJ, Wombacher R, Fackler OT. Intrinsic properties and plasma membrane trafficking route of Src family kinase SH4 domains sensitive to retargeting by HIV-1 Nef. J Biol Chem 2018; 293:7824-7840. [PMID: 29588370 DOI: 10.1074/jbc.ra118.002794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Indexed: 01/18/2023] Open
Abstract
The HIV type 1 pathogenicity factor Nef enhances viral replication by modulating multiple host cell pathways, including tuning the activation state of infected CD4 T lymphocytes to optimize virus spread. For this, Nef inhibits anterograde transport of the Src family kinase (SFK) Lck toward the plasma membrane (PM). This leads to retargeting of the kinase to the trans-Golgi network, whereas the intracellular transport of a related SFK, Fyn, is unaffected by Nef. The 18-amino acid Src homology 4 (SH4) domain membrane anchor of Lck is necessary and sufficient for Nef-mediated retargeting, but other details of this process are not known. The goal of this study was therefore to identify characteristics of SH4 domains responsive to Nef and the transport machinery used. Screening a panel of SFK SH4 domains revealed two groups that were sensitive or insensitive for trans-Golgi network retargeting by Nef as well as the importance of the amino acid at position 8 for determining Nef sensitivity. Anterograde transport of Nef-sensitive domains was characterized by slower delivery to the PM and initial targeting to Golgi membranes, where transport was arrested in the presence of Nef. For Nef-sensitive SH4 domains, ectopic expression of the lipoprotein binding chaperone Unc119a or the GTPase Arl3 or reduction of their endogenous expression phenocopied the effect of Nef. Together, these results suggest that, analogous to K-Ras, Nef-sensitive SH4 domains are transported to the PM by a cycle of solubilization and membrane insertion and that intrinsic properties define SH4 domains as cargo of this Nef-sensitive lipoprotein binding chaperone-GTPase transport cycle.
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Affiliation(s)
- Amanda J Chase
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Rebecka Wombacher
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
| | - Oliver T Fackler
- From the Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, University Hospital Heidelberg, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany
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28
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Mlcochova P, Caswell SJ, Taylor IA, Towers GJ, Gupta RK. DNA damage induced by topoisomerase inhibitors activates SAMHD1 and blocks HIV-1 infection of macrophages. EMBO J 2018; 37:50-62. [PMID: 29084722 PMCID: PMC5753034 DOI: 10.15252/embj.201796880] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 09/19/2017] [Accepted: 09/22/2017] [Indexed: 12/15/2022] Open
Abstract
We report that DNA damage induced by topoisomerase inhibitors, including etoposide (ETO), results in a potent block to HIV-1 infection in human monocyte-derived macrophages (MDM). SAMHD1 suppresses viral reverse transcription (RT) through depletion of cellular dNTPs but is naturally switched off by phosphorylation in a subpopulation of MDM found in a G1-like state. We report that SAMHD1 was activated by dephosphorylation following ETO treatment, along with loss of expression of MCM2 and CDK1, and reduction in dNTP levels. Suppression of infection occurred after completion of viral DNA synthesis, at the step of 2LTR circle and provirus formation. The ETO-induced block was completely rescued by depletion of SAMHD1 in MDM Concordantly, infection by HIV-2 and SIVsm encoding the SAMHD1 antagonist Vpx was insensitive to ETO treatment. The mechanism of DNA damage-induced blockade of HIV-1 infection involved activation of p53, p21, decrease in CDK1 expression, and SAMHD1 dephosphorylation. Therefore, topoisomerase inhibitors regulate SAMHD1 and HIV permissivity at a post-RT step, revealing a mechanism by which the HIV-1 reservoir may be limited by chemotherapeutic drugs.
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Affiliation(s)
| | - Sarah J Caswell
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
| | | | - Ravindra K Gupta
- Division of Infection and Immunity, UCL, London, UK
- Africa Health Research Institute, Durban, KwaZulu Natal, South Africa
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29
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Asadian P, Finnie G, Bienzle D. The expression profile of sterile alpha motif and histidine-aspartate domain-containing protein 1 (SAMHD1) in feline tissues. Vet Immunol Immunopathol 2017; 195:7-18. [PMID: 29249320 DOI: 10.1016/j.vetimm.2017.11.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 10/29/2017] [Accepted: 11/02/2017] [Indexed: 12/15/2022]
Abstract
SAMHD1 restricts lentiviruses by limiting availability of deoxynucleoside triphosphates for reverse transcription. HIV-2 and SIV have virion-associated proteins to counteract SAMHD1. Cats have an ortholog to human SAMHD1 and the FIV is restricted by human SAMHD1, but expression of feline SAMHD1 is unknown. Using a whole-body tissue microarray consisting of 24 tissues for immunohistochemistry, SAMHD1 expression was identified in a wide range of cat tissues. SAMHD1 was most strongly expressed in skin and mucosal epithelium, and in hemolymphatic and spermatogenic tissues. Both nuclear and cytoplasmic expression was detected. Feline cell lines susceptible to FIV infection also highly expressed SAMHD1. Preferential expression of SAMHD1 at sites of viral entry and replication supports a role for feline SAMHD1 in restricting FIV.
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Affiliation(s)
- Peyman Asadian
- Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Gillian Finnie
- Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Dorothee Bienzle
- Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2W1, Canada.
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30
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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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31
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Jobe O, Kim J, Tycksen E, Onkar S, Michael NL, Alving CR, Rao M. Human Primary Macrophages Derived In Vitro from Circulating Monocytes Comprise Adherent and Non-Adherent Subsets with Differential Expression of Siglec-1 and CD4 and Permissiveness to HIV-1 Infection. Front Immunol 2017; 8:1352. [PMID: 29123518 PMCID: PMC5662875 DOI: 10.3389/fimmu.2017.01352] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/03/2017] [Indexed: 12/18/2022] Open
Abstract
Macrophages are a major target for human immunodeficiency virus type 1 (HIV-1) infection. However, macrophages are largely heterogeneous and may exhibit differences in permissiveness to HIV-1 infection. This study highlights the interplay of macrophage heterogeneity in HIV-1 pathogenesis. We show that monocyte-derived macrophages (MDMs) could be divided into two distinct subsets: CD14+Siglec-1hiCD4+ (non-adherent MDM) and CD14+Siglec-1LoCD4− (adherent MDM). The CD14+Siglec-1hiCD4+MDM subset represented the smaller proportion in the macrophage pool, and varied among different donors. Fractionation and subsequent exposure of the two MDM subsets to HIV-1 revealed opposite outcomes in terms of HIV-1 capture and infection. Although the CD14+Siglec-1hiCD4+MDM captured significantly more HIV-1, infection was significantly higher in the CD14+Siglec-1LoCD4−MDM subset. Thus, CD14+Siglec-1hiCD4+MDM were less permissive to infection. Depletion of CD14+Siglec-1hiCD4+MDM or a decrease in their percentage, resulted in increased infection of MDM, suggestive of a capacity of these cells to capture and sequester HIV-1 in an environment that hinders its infectivity. Increased expression of innate restriction factors and cytokine genes were observed in the non-adherent CD14+Siglec-1hiCD4+MDM, both before and after HIV-1 infection, compared to the adherent CD14+Siglec-1LoCD4−MDM. We speculate that the differential expression of gene expression profiles in the two macrophage subsets may provide an explanation for the differences observed in HIV-1 infectivity.
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Affiliation(s)
- Ousman Jobe
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, United States.,Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Jiae Kim
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, United States.,Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Eric Tycksen
- Genome Technology Access Center, Department of Genetics, Washington University in St. Louis, St. Louis, MO, United States
| | - Sayali Onkar
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, United States.,Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Nelson L Michael
- Laboratory of Molecular Virology and Pathogenesis, Host Genetics Section, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Carl R Alving
- Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Mangala Rao
- Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, United States
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32
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Irwin CR, Hitt MM, Evans DH. Targeting Nucleotide Biosynthesis: A Strategy for Improving the Oncolytic Potential of DNA Viruses. Front Oncol 2017; 7:229. [PMID: 29018771 PMCID: PMC5622948 DOI: 10.3389/fonc.2017.00229] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022] Open
Abstract
The rapid growth of tumors depends upon elevated levels of dNTPs, and while dNTP concentrations are tightly regulated in normal cells, this control is often lost in transformed cells. This feature of cancer cells has been used to advantage to develop oncolytic DNA viruses. DNA viruses employ many different mechanisms to increase dNTP levels in infected cells, because the low concentration of dNTPs found in non-cycling cells can inhibit virus replication. By disrupting the virus-encoded gene(s) that normally promote dNTP biosynthesis, one can assemble oncolytic versions of these agents that replicate selectively in cancer cells. This review covers the pathways involved in dNTP production, how they are dysregulated in cancer cells, and the various approaches that have been used to exploit this biology to improve the tumor specificity of oncolytic viruses. In particular, we compare and contrast the ways that the different types of oncolytic virus candidates can directly modulate these processes. We limit our review to the large DNA viruses that naturally encode homologs of the cellular enzymes that catalyze dNTP biogenesis. Lastly, we consider how this knowledge might guide future development of oncolytic viruses.
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Affiliation(s)
- Chad R Irwin
- Faculty of Medicine and Dentistry, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada
| | - Mary M Hitt
- Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - David H Evans
- Faculty of Medicine and Dentistry, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Faculty of Medicine and Dentistry, Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB, Canada
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33
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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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34
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Mlcochova P, Sutherland KA, Watters SA, Bertoli C, de Bruin RA, Rehwinkel J, Neil SJ, Lenzi GM, Kim B, Khwaja A, Gage MC, Georgiou C, Chittka A, Yona S, Noursadeghi M, Towers GJ, Gupta RK. A G1-like state allows HIV-1 to bypass SAMHD1 restriction in macrophages. EMBO J 2017; 36:604-616. [PMID: 28122869 PMCID: PMC5331754 DOI: 10.15252/embj.201696025] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 01/09/2023] Open
Abstract
An unresolved question is how HIV-1 achieves efficient replication in terminally differentiated macrophages despite the restriction factor SAMHD1. We reveal inducible changes in expression of cell cycle-associated proteins including MCM2 and cyclins A, E, D1/D3 in macrophages, without evidence for DNA synthesis or mitosis. These changes are induced by activation of the Raf/MEK/ERK kinase cascade, culminating in upregulation of CDK1 with subsequent SAMHD1 T592 phosphorylation and deactivation of its antiviral activity. HIV infection is limited to these G1-like phase macrophages at the single-cell level. Depletion of SAMHD1 in macrophages decouples the association between infection and expression of cell cycle-associated proteins, with terminally differentiated macrophages becoming highly susceptible to HIV-1. We observe both embryo-derived and monocyte-derived tissue-resident macrophages in a G1-like phase at frequencies approaching 20%, suggesting how macrophages sustain HIV-1 replication in vivo Finally, we reveal a SAMHD1-dependent antiretroviral activity of histone deacetylase inhibitors acting via p53 activation. These data provide a basis for host-directed therapeutic approaches aimed at limiting HIV-1 burden in macrophages that may contribute to curative interventions.
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Affiliation(s)
- Petra Mlcochova
- Division of Infection and Immunity, University College London, London, UK
| | | | - Sarah A Watters
- Division of Infection and Immunity, University College London, London, UK
| | - Cosetta Bertoli
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Rob Am de Bruin
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Jan Rehwinkel
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Stuart J Neil
- Division of Immunology, Infection and Inflammatory Disease, King's College, London, UK
| | - Gina M Lenzi
- Department of Pediatrics, Center for Drug Discovery, Emory School of Medicine, Atlanta, GA, USA
| | - Baek Kim
- Department of Pediatrics, Center for Drug Discovery, Emory School of Medicine, Atlanta, GA, USA
| | - Asim Khwaja
- Research Department of Haematology, UCL, London, UK
| | - Matthew C Gage
- Division of Medicine, University College London, London, UK
| | | | | | - Simon Yona
- Division of Medicine, University College London, London, UK
| | - Mahdad Noursadeghi
- Division of Infection and Immunity, University College London, London, UK
| | - Greg J Towers
- Division of Infection and Immunity, University College London, London, UK
| | - Ravindra K Gupta
- Division of Infection and Immunity, University College London, London, UK
- Africa Health Research Institute, KwaZulu Natal, South Africa
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35
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Vpx overcomes a SAMHD1-independent block to HIV reverse transcription that is specific to resting CD4 T cells. Proc Natl Acad Sci U S A 2017; 114:2729-2734. [PMID: 28228523 DOI: 10.1073/pnas.1613635114] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Early after entry into monocytes, macrophages, dendritic cells, and resting CD4 T cells, HIV encounters a block, limiting reverse transcription (RT) of the incoming viral RNA genome. In this context, dNTP triphosphohydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) has been identified as a restriction factor, lowering the concentration of dNTP substrates to limit RT. The accessory lentiviral protein X (Vpx) proteins from the major simian immunodeficiency virus of rhesus macaque, sooty mangabey, and HIV-2 (SIVsmm/SIVmac/HIV-2) lineage packaged into virions target SAMHD1 for proteasomal degradation, increase intracellular dNTP pools, and facilitate HIV cDNA synthesis. We find that virion-packaged Vpx proteins from a second SIV lineage, SIV of red-capped mangabeys or mandrills (SIVrcm/mnd-2), increased HIV infection in resting CD4 T cells, but not in macrophages, and, unexpectedly, acted in the absence of SAMHD1 degradation, dNTP pool elevation, or changes in SAMHD1 phosphorylation. Vpx rcm/mnd-2 virion incorporation resulted in a dramatic increase of HIV-1 RT intermediates and viral cDNA in infected resting CD4 T cells. These analyses also revealed a barrier limiting HIV-1 infection of resting CD4 T cells at the level of nuclear import. Single amino acid changes in the SAMHD1-degrading Vpx mac239 allowed it to enhance early postentry steps in a Vpx rcm/mnd-2-like fashion. Moreover, Vpx enhanced HIV-1 infection of SAMHD1-deficient resting CD4 T cells of a patient with Aicardi-Goutières syndrome. These results indicate that Vpx, in addition to SAMHD1, overcomes a previously unappreciated restriction for lentiviruses at the level of RT that acts independently of dNTP concentrations and is specific to resting CD4 T cells.
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36
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Riess M, Fuchs NV, Idica A, Hamdorf M, Flory E, Pedersen IM, König R. Interferons Induce Expression of SAMHD1 in Monocytes through Down-regulation of miR-181a and miR-30a. J Biol Chem 2016; 292:264-277. [PMID: 27909056 DOI: 10.1074/jbc.m116.752584] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 11/29/2016] [Indexed: 01/01/2023] Open
Abstract
SAMHD1 is a phosphohydrolase maintaining cellular dNTP homeostasis but also acts as a critical regulator in innate immune responses due to its antiviral activity and association with autoimmune disease, leading to aberrant activation of interferon. SAMHD1 expression is differentially regulated by interferon in certain primary cells, but the underlying mechanism is not understood. Here, we report a detailed characterization of the promotor region, the 5'- and 3'-untranslated region (UTR) of SAMHD1, and the mechanism responsible for the cell type-dependent up-regulation of SAMHD1 protein by interferon. We demonstrate that induction of SAMHD1 by type I and II interferons depends on 3'-UTR post-transcriptional regulation, whereas the promoter drives basal expression levels. We reveal novel functional target sites for the microRNAs miR-181a, miR-30a, and miR-155 in the SAMHD1 3'-UTR. Furthermore, we demonstrate that down-regulation of endogenous miR-181a and miR-30a levels inversely correlates with SAMHD1 protein up-regulation upon type I and II interferon stimulation in primary human monocytes. These miRNAs are not modulated by interferon in macrophages or dendritic cells, and consequently protein levels of SAMHD1 remain unchanged. These results suggest that SAMHD1 is a non-classical interferon-stimulated gene regulated through cell type-dependent down-regulation of miR-181a and miR-30a in innate sentinel cells.
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Affiliation(s)
| | | | - Adam Idica
- the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697
| | - Matthias Hamdorf
- the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697
| | - Egbert Flory
- the Division of Medical Biotechnology, Paul-Ehrlich-Institute, 63225 Langen, Germany
| | - Irene Munk Pedersen
- the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697
| | - Renate König
- From the Host-Pathogen Interactions Group and .,the Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, and.,the German Center for Infection Research (DZIF), 63225 Langen, Germany
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Borsotti C, Borroni E, Follenzi A. Lentiviral vector interactions with the host cell. Curr Opin Virol 2016; 21:102-108. [PMID: 27637073 DOI: 10.1016/j.coviro.2016.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 10/21/2022]
Abstract
Lentiviral vectors (LVs)-mediated gene transfer is an efficient method for ex vivo and in vivo gene therapy. Actually, LVs have been used in several clinical trials and therapeutic correction was reached in affected patients. However, in order to be effective gene therapy needs to be efficient without detrimental effects for target cells. Successful cell transduction by LVs can be hampered by several factors such as the activation of innate immune sensors during cell transduction and different restriction factors (RFs) inhibiting viral replication inside the cells. Therefore, a better knowledge of host-vector interactions is important for the development of more efficient gene therapy strategies improving the LVs platform by limiting harmful responses.
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Affiliation(s)
- Chiara Borsotti
- Department of Health Sciences, Università del Piemonte Orientale "A. Avogadro", Novara 28100, Italy
| | - Ester Borroni
- Department of Health Sciences, Università del Piemonte Orientale "A. Avogadro", Novara 28100, Italy
| | - Antonia Follenzi
- Department of Health Sciences, Università del Piemonte Orientale "A. Avogadro", Novara 28100, Italy.
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Interferon-induced sterile alpha motif and histidine/aspartic acid domain-containing protein 1 expression in astrocytes and microglia is mediated by microRNA-181a. AIDS 2016; 30:2053-64. [PMID: 27219130 DOI: 10.1097/qad.0000000000001166] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Sterile alpha motif and histidine/aspartic acid domain-containing protein 1 (SAMHD1), a newly discovered HIV-1 host restriction factor, has been found to be induced by interferons and to be regulated by microRNA-181a (miR-181a). However, the mechanism of interferons-induced SAMHD1 expression is unclear. DESIGN We hypothesized that interferons induce SAMHD1 expression through Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathways, which is mediated by miR-181a. METHODS We examined the effect of IFN-α and IFN-γ on SAMHD1 mRNA and protein expression, as well as the levels of phosphorylated SAMHD1 and miR-181a in astrocytes and microglia. To determine whether interferons-induced SAMHD1 expression was mediated by miR-181a, we overexpressed or inhibited miR-181a in these cells and exposed them to interferons. We also detected the effect of SAMHD1 and miR-181a on HIV-1 infection in astrocytes and microglia. RESULTS Both IFN-α and IFN-γ increased SAMHD1 mRNA and protein expression, and reduced miR-181a levels, particularly in microglia. Phosphorylated SAMHD1was not induced by interferons. Overexpression of miR-181a counteracted induction of SAMHD1 expression by interferons, and inhibition of miR-181a mimicked interferons treatment. Inhibition of JAK-STAT signaling pathways resulted in increased miR-181a levels and decreased SAMHD1 mRNA expression. Knock-down of SAMHD1 or overexpression of miR-181a enhanced HIV-1 infection, whereas inhibition of miR-181a reduced HIV-1 infection. However, inhibition of HIV-1 infection induced by IFN-α was not significantly affected by miR-181a and SAMHD1. CONCLUSION MiR-181a is an important mediator for interferons-induced SAMHD1 expression in astrocytes and microglia, but not for inhibition of HIV-1 infection induced by IFN-α.
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Rausell A, Muñoz M, Martinez R, Roger T, Telenti A, Ciuffi A. Innate immune defects in HIV permissive cell lines. Retrovirology 2016; 13:43. [PMID: 27350062 PMCID: PMC4924258 DOI: 10.1186/s12977-016-0275-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/14/2016] [Indexed: 11/29/2022] Open
Abstract
Background Primary CD4+ T cells and cell lines differ in their permissiveness to HIV infection. Impaired innate immunity may contribute to this different phenotype. Findings We used transcriptome profiling of 1503 innate immunity genes in primary CD4+ T cells and permissive cell lines. Two clusters of differentially expressed genes were identified: a set of 249 genes that were highly expressed in primary cells and minimally expressed in cell lines and a set of 110 genes with the opposite pattern. Specific to HIV, HEK293T, Jurkat, SupT1 and CEM cell lines displayed unique patterns of downregulation of genes involved in viral sensing and restriction. Activation of primary CD4+ T cells resulted in reversal of the pattern of expression of those sets of innate immunity genes. Functional analysis of prototypical innate immunity pathways of permissive cell lines confirmed impaired responses identified in transcriptome analyses. Conclusion Integrity of innate immunity genes and pathways needs to be considered in designing gain/loss functional genomic screens of viral infection. Electronic supplementary material The online version of this article (doi:10.1186/s12977-016-0275-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Antonio Rausell
- Clinical Bioinformatics lab, Imagine Institute, Paris Descartes University - Sorbonne Paris Cité, 75015, Paris, France.
| | - Miguel Muñoz
- Institute of Microbiology, University Hospital of Lausanne (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland
| | - Raquel Martinez
- Institute of Microbiology, University Hospital of Lausanne (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland
| | - Thierry Roger
- Infectious Diseases Service, Department of Medicine, University Hospital of Lausanne (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland
| | - Amalio Telenti
- Genetic Medicine, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - Angela Ciuffi
- Institute of Microbiology, University Hospital of Lausanne (CHUV) and University of Lausanne, 1011, Lausanne, Switzerland
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Coiras M, Bermejo M, Descours B, Mateos E, García-Pérez J, López-Huertas MR, Lederman MM, Benkirane M, Alcamí J. IL-7 Induces SAMHD1 Phosphorylation in CD4+ T Lymphocytes, Improving Early Steps of HIV-1 Life Cycle. Cell Rep 2016; 14:2100-2107. [PMID: 26923586 PMCID: PMC5063304 DOI: 10.1016/j.celrep.2016.02.022] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 12/10/2015] [Accepted: 01/29/2016] [Indexed: 01/12/2023] Open
Abstract
HIV-1 post-integration latency in CD4+ lymphocytes is responsible for viral persistence despite treatment, but mechanisms involved in the establishment of latent viral reservoirs are not fully understood. We determined that both interleukin 2 (IL-2) and IL-7 induced SAMHD1 phosphorylation in T592, abrogating its antiviral activity. However, IL-7 caused a much more profound stimulatory effect on HIV-1 reverse transcription and integration than IL-2 that required chemokine co-stimulation. Both cytokines barely induced transcription due to low NF-κB induction, favoring the establishment of latent reservoirs. Effect of IL-7 on SAMHD1 phosphorylation was confirmed in IL-7-treated patients (ACTG 5214 study). Dasatinib—a tyrosine-kinase inhibitor—blocked SAMHD1 phosphorylation induced by IL-2 and IL-7 and restored HIV-1 restriction. We propose that γc-cytokines play a major role in the reservoir establishment not only by driving homeostatic proliferation but also by increasing susceptibility of CD4+ lymphocytes to HIV-1 infection through SAMHD1 inactivation.
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Affiliation(s)
- Mayte Coiras
- AIDS Immunopathogenesis Unit, Instituto de Salud Carlos III, Madrid 28220, Spain.
| | - Mercedes Bermejo
- AIDS Immunopathogenesis Unit, Instituto de Salud Carlos III, Madrid 28220, Spain
| | - Benjamin Descours
- Institut de Génétique Humaine CNRS UPR1142, Université de Montpellier, Laboratoire de Virologie Moléculaire, Montpellier 34000, France
| | - Elena Mateos
- AIDS Immunopathogenesis Unit, Instituto de Salud Carlos III, Madrid 28220, Spain
| | - Javier García-Pérez
- AIDS Immunopathogenesis Unit, Instituto de Salud Carlos III, Madrid 28220, Spain
| | | | - Michael M Lederman
- Case Western Reserve University, University Hospitals Case Medical Center, Cleveland, OH 44106, USA
| | - Monsef Benkirane
- Institut de Génétique Humaine CNRS UPR1142, Université de Montpellier, Laboratoire de Virologie Moléculaire, Montpellier 34000, France
| | - José Alcamí
- AIDS Immunopathogenesis Unit, Instituto de Salud Carlos III, Madrid 28220, Spain.
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Kim KA, Jeong JJ, Yoo SY, Kim DH. Gut microbiota lipopolysaccharide accelerates inflamm-aging in mice. BMC Microbiol 2016; 16:9. [PMID: 26772806 PMCID: PMC4715324 DOI: 10.1186/s12866-016-0625-7] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 01/08/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The constitutive inflammation that characterizes advanced age is termed inflamm-aging. This process is associated with age-related changes to immune homeostasis and gut microbiota. We investigated the relationship between aging and gut microbiota lipopolysaccharide (LPS)-inducible inflammation. RESULTS A taxonomy-based analysis showed that aging resulted in increased prevalence of the phyla Firmicutes and Actinobacteria and a reduced prevalence of Bacteroidetes and Tenericutes, resulting in an increase in the Firmicutes to Bacteroidetes ratio. The levels of plasmatic and fecal lipopolysaccharides were higher in aged mice. Aging induced the expression of p16 and the activation of nuclear factor-kappa B (NF-κB) in the colon of aged mice. Interestingly, the expression level of sterile α-motif domain- and HD domain-containing protein 1 (SAMHD1) in the colon was higher in aged mice than in young mice, while cyclin-dependent kinase-2 and cyclin E levels were lower in aged mice than in young mice. The lipopolysaccharide fraction of fecal lysates (LFL) from young or aged mice increased p16 and SAMHD1 expression and NF-κB activation in peritoneal macrophages from wild-type mice, in a TLR4-dependent manner. However, LFLs did not induce NF-κB activation and SAMHD1 expression in peritoneal macrophages from TLR4-deificent mice, whereas they significantly induced p16 expression. Nevertheless, p16 expression was induced more potently in macrophages from WT mice than in macrophages from TLR4-deficient mice. CONCLUSION Aging increased p16 and SAMHD1 expression, gut microbiota LPS production, and NF-κB activation; thereby, signifying that gut microbiota LPS may accelerate inflamm-aging and SAMHD1 may be an inflamm-aging marker.
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Affiliation(s)
- Kyung-Ah Kim
- Department of Life and Nanopharmaceutical Sciences, College of Pharmacy, Kyung Hee University, 1, Hoegi, Dongdaemun-ku, Seoul, 130-701, Korea.,Department of Food and Nutrition, Song Won University, 73, Songamro, Nam-gu, Gwangju, 503-742, Korea
| | - Jin-Ju Jeong
- Department of Life and Nanopharmaceutical Sciences, College of Pharmacy, Kyung Hee University, 1, Hoegi, Dongdaemun-ku, Seoul, 130-701, Korea
| | - Sul-Young Yoo
- Department of Life and Nanopharmaceutical Sciences, College of Pharmacy, Kyung Hee University, 1, Hoegi, Dongdaemun-ku, Seoul, 130-701, Korea
| | - Dong-Hyun Kim
- Department of Life and Nanopharmaceutical Sciences, College of Pharmacy, Kyung Hee University, 1, Hoegi, Dongdaemun-ku, Seoul, 130-701, Korea.
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Dragin L, Munir-Matloob S, Froehlich J, Morel M, Sourisce A, Lahouassa H, Bailly K, Mangeney M, Ramirez BC, Margottin-Goguet F. Evidence that HIV-1 restriction factor SAMHD1 facilitates differentiation of myeloid THP-1 cells. Virol J 2015; 12:201. [PMID: 26606981 PMCID: PMC4660839 DOI: 10.1186/s12985-015-0425-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 11/15/2015] [Indexed: 12/12/2022] Open
Abstract
Background SAMHD1 counteracts HIV-1 or HIV-2/SIVsmm that lacks Vpx by depleting the intracellular pool of nucleotides in myeloid cells and CD4+ quiescent T cells, thereby inhibiting the synthesis of retroviral DNA by reverse transcriptase. Depletion of nucleotides has been shown to underline the establishment of quiescence in certain cellular systems. These observations led us to investigate whether SAMHD1 could control the transition between proliferation and quiescence using the THP-1 cell model. Findings The entry of dividing THP-1 myeloid cells into a non-dividing differentiated state was monitored after addition of phorbol-12-myristate-13-acetate (PMA), an inducer of differentiation. Under PMA treatment, cells overexpressing SAMHD1 display stronger and faster adhesion to their support, compared to cells expressing a catalytically inactive form of SAMHD1, or cells depleted of SAMHD1, which appear less differentiated. After PMA removal, cells overexpressing SAMHD1 maintain low levels of cyclin A, in contrast to other cell lines. Interestingly, SAMHD1 overexpression slightly increases cell adhesion even in the absence of the differentiation inducer PMA. Finally, we found that levels of SAMHD1 are reduced in proliferating primary CD4+ T cells after T cell receptor activation, suggesting that SAMHD1 may also be involved in the transition from a quiescent state to a dividing state in primary T cells. Conclusions Altogether, we provide evidence that SAMHD1 may facilitate some aspects of THP-1 cell differentiation. Restriction of HIV-1 by SAMHD1 may rely upon its ability to modify cell cycle parameters, in addition to the direct inhibition of reverse transcription. Electronic supplementary material The online version of this article (doi:10.1186/s12985-015-0425-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Loic Dragin
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Soundasse Munir-Matloob
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Jeanne Froehlich
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Marina Morel
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Adèle Sourisce
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Hichem Lahouassa
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Karine Bailly
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Marianne Mangeney
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Bertha Cecilia Ramirez
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
| | - Florence Margottin-Goguet
- Inserm, U1016, Institut Cochin, 22 rue Méchain, 75014, Paris, France. .,CNRS, UMR8104, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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Ballana E, Esté JA. SAMHD1: at the crossroads of cell proliferation, immune responses, and virus restriction. Trends Microbiol 2015; 23:680-692. [PMID: 26439297 DOI: 10.1016/j.tim.2015.08.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/28/2015] [Accepted: 08/07/2015] [Indexed: 12/31/2022]
Abstract
SAMHD1 is a triphosphohydrolase enzyme that controls the intracellular level of deoxyribonucleoside triphosphates (dNTPs) and plays a role in innate immune sensing and autoimmune disease. SAMHD1 has also been identified as an intrinsic virus restriction factor, inactivated through degradation by HIV-2 Vpx or through a post-transcriptional regulatory mechanism. Phosphorylation of SAMHD1 by cyclin-dependent kinases has been strongly associated with inactivation of the virus restriction mechanism, providing an association between virus replication and cell proliferation. Tight regulation of cell proliferation suggests that viruses, particularly HIV-1 replication, latency, and reactivation, may be similarly controlled by multiple checkpoint mechanisms that, in turn, regulate dNTP levels. In this review, we discuss how SAMHD1 is a viral restriction factor, the mechanism associated with viral restriction, the pathway leading to its inactivation in proliferating cells, and how strategies aimed at controlling virus restriction could lead to a functional cure for HIV.
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Affiliation(s)
- Ester Ballana
- AIDS Research Institute-IrsiCaixa and Health Research Institute Germans Trias i Pujol (IGTP), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - José A Esté
- AIDS Research Institute-IrsiCaixa and Health Research Institute Germans Trias i Pujol (IGTP), Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain.
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Franzolin E, Salata C, Bianchi V, Rampazzo C. The Deoxynucleoside Triphosphate Triphosphohydrolase Activity of SAMHD1 Protein Contributes to the Mitochondrial DNA Depletion Associated with Genetic Deficiency of Deoxyguanosine Kinase. J Biol Chem 2015; 290:25986-96. [PMID: 26342080 PMCID: PMC4646252 DOI: 10.1074/jbc.m115.675082] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Indexed: 11/22/2022] Open
Abstract
The dNTP triphosphohydrolase SAMHD1 is a nuclear antiviral host restriction factor limiting HIV-1 infection in macrophages and a major regulator of dNTP concentrations in human cells. In normal human fibroblasts its expression increases during quiescence, contributing to the small dNTP pool sizes of these cells. Down-regulation of SAMHD1 by siRNA expands all four dNTP pools, with dGTP undergoing the largest relative increase. The deoxyguanosine released by SAMHD1 from dGTP can be phosphorylated inside mitochondria by deoxyguanosine kinase (dGK) or degraded in the cytosol by purine nucleoside phosphorylase. Genetic mutations of dGK cause mitochondrial (mt) DNA depletion in noncycling cells and hepato-cerebral mtDNA depletion syndrome in humans. We studied if SAMHD1 and dGK interact in the regulation of the dGTP pool during quiescence employing dGK-mutated skin fibroblasts derived from three unrelated patients. In the presence of SAMHD1 quiescent mutant fibroblasts manifested mt dNTP pool imbalance and mtDNA depletion. When SAMHD1 was silenced by siRNA transfection the composition of the mt dNTP pool approached that of the controls, and mtDNA copy number increased, compensating the depletion to various degrees in the different mutant fibroblasts. Chemical inhibition of purine nucleoside phosphorylase did not improve deoxyguanosine recycling by dGK in WT cells. We conclude that the activity of SAMHD1 contributes to the pathological phenotype of dGK deficiency. Our results prove the importance of SAMHD1 in the regulation of all dNTP pools and suggest that dGK inside mitochondria has the function of recycling the deoxyguanosine derived from endogenous dGTP degraded by SAMHD1 in the nucleus.
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Affiliation(s)
- Elisa Franzolin
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
| | - Cristiano Salata
- Department of Molecular Medicine, University of Padova, 35121 Padova, Italy
| | - Vera Bianchi
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
| | - Chiara Rampazzo
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
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Appelberg KS, Goodenow MM. Editorial: Passive aggressive avoidance of SAMHD1 restriction by HIV-1. J Leukoc Biol 2015; 98:1-3. [DOI: 10.1189/jlb.4ce0215-044r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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