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Li Z, He H, Ren X, Chen Y, Liu W, Pu R, Fang L, Shi Y, Liu D, Zhao J, Niu Z, Xu M, Cao G. APOBEC3A suppresses cervical cancer via apoptosis. J Cancer 2023; 14:3429-3443. [PMID: 38021159 PMCID: PMC10647198 DOI: 10.7150/jca.89044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 09/25/2023] [Indexed: 12/01/2023] Open
Abstract
Background: Family members of Apolipoprotein B mRNA-editing enzyme catalytic 3 (APOBEC3) play critical roles in cancer evolution and development. However, the role of APOBEC3A in cervical cancer remains to be clarified. Methods: We used bioinformatics to investigate APOBEC3A expression and outcomes using The Cancer Genome Atlas (TCGA)-cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) dataset, GTEx, and GSE7803. Immunohistochemistry was then used to identify APOBEC3A's expression pattern. We performed Cell Counting Kit-8, wound-healing, Transwell, and flow cytometry assays to measure proliferation, migration, invasion, and apoptosis, respectively, using the SiHa and HeLa cell lines transfected with APOBEC3A. BALB/c nude mice were used to investigate the effects of APOBEC3A in vivo. The phosphorylated gamma-H2AX staining assay was applied to measure DNA damage. RNA sequencing (RNA-Seq) was applied to explore APOBEC3A-related signaling pathways. Results: APOBEC3A was more significantly expressed in cancer tissues than in adjacent normal tissues. Higher expression of APOBEC3A was associated with better outcomes in TCGA-CESC and GTEx. Immunohistochemistry showed that the expression of APOBEC3A was significantly higher in cancer tissues than in normal tissues. Transfection experiments showed that APOBEC3A inhibited proliferation, upregulated S-phase cells, inhibited migration and invasion, induced DNA damage, and promoted apoptosis. Overexpression of APOBEC3A inhibited tumor formation in the mouse model. RNA-seq analysis showed that ectopic expression of APOBEC3A inhibited several cancer-associated signaling pathways. Conclusions: APOBEC3A is significantly upregulated in cervical cancer, and higher expression of APOBEC3A is associated with better outcomes. APOBEC3A is a tumor suppressor whose overexpression induces apoptosis in cervical cancer.
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Affiliation(s)
- Zishuai Li
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Haiwei He
- Department of Obstetrics and Gynecology, the 1st Affiliated Hospital, Second Military Medical University, Shanghai 200433, China
| | - Xiangyu Ren
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Yifan Chen
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Wenbin Liu
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Rui Pu
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Letian Fang
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Yiwei Shi
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Donghong Liu
- Department of Hepatic Surgery, the 3rd Affiliated Hospital, Second Military Medical University, Shanghai, 200438, China
| | - Jiayi Zhao
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
| | - Zheyun Niu
- Shanghai East Hospital, Key Laboratory of Arrhythmias, Ministry of Education, Tongji University School of Medicine Tongji University, Shanghai 200120, China
| | - Mingjuan Xu
- Department of Obstetrics and Gynecology, the 1st Affiliated Hospital, Second Military Medical University, Shanghai 200433, China
| | - Guangwen Cao
- Department of Epidemiology, Second Military Medical University, Shanghai, 200433, China
- Shanghai Key Laboratory of Medical Bioprotection, Shanghai, 200433, China
- Key Laboratory of Biological Defense, Ministry of Education, Shanghai, 200433, China
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Fanunza E, Cheng AZ, Auerbach AA, Stefanovska B, Moraes SN, Lokensgard JR, Biolatti M, Dell'Oste V, Bierle CJ, Bresnahan WA, Harris RS. Human cytomegalovirus mediates APOBEC3B relocalization early during infection through a ribonucleotide reductase-independent mechanism. J Virol 2023; 97:e0078123. [PMID: 37565748 PMCID: PMC10506462 DOI: 10.1128/jvi.00781-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 06/21/2023] [Indexed: 08/12/2023] Open
Abstract
The APOBEC3 family of DNA cytosine deaminases comprises an important arm of the innate antiviral defense system. The gamma-herpesviruses Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus and the alpha-herpesviruses herpes simplex virus (HSV)-1 and HSV-2 have evolved an efficient mechanism to avoid APOBEC3 restriction by directly binding to APOBEC3B and facilitating its exclusion from the nuclear compartment. The only viral protein required for APOBEC3B relocalization is the large subunit of the ribonucleotide reductase (RNR). Here, we ask whether this APOBEC3B relocalization mechanism is conserved with the beta-herpesvirus human cytomegalovirus (HCMV). Although HCMV infection causes APOBEC3B relocalization from the nucleus to the cytoplasm in multiple cell types, the viral RNR (UL45) is not required. APOBEC3B relocalization occurs rapidly following infection suggesting the involvement of an immediate early or early (IE/E) viral protein. In support of this possibility, genetic (IE1 mutant) and pharmacologic (cycloheximide) strategies that prevent the expression of IE/E viral proteins also block APOBEC3B relocalization. In comparison, the treatment of infected cells with phosphonoacetic acid, which interferes with viral late protein expression, still permits A3B relocalization. These results combine to indicate that the beta-herpesvirus HCMV uses an RNR-independent, yet phenotypically similar, molecular mechanism to antagonize APOBEC3B. IMPORTANCE Human cytomegalovirus (HCMV) infections can range from asymptomatic to severe, particularly in neonates and immunocompromised patients. HCMV has evolved strategies to overcome host-encoded antiviral defenses to achieve lytic viral DNA replication and dissemination and, under some conditions, latency and long-term persistence. Here, we show that HCMV infection causes the antiviral factor, APOBEC3B, to relocalize from the nuclear compartment to the cytoplasm. This overall strategy resembles that used by related herpesviruses. However, the HCMV relocalization mechanism utilizes a different viral factor(s) and available evidence suggests the involvement of at least one protein expressed at the early stages of infection. This knowledge is important because a greater understanding of this mechanism could lead to novel antiviral strategies that enable APOBEC3B to naturally restrict HCMV infection.
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Affiliation(s)
- Elisa Fanunza
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, Cagilari, Italy
| | - Adam Z. Cheng
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Ashley A. Auerbach
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Bojana Stefanovska
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
- Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Sofia N. Moraes
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - James R. Lokensgard
- Department of Medicine, University of Minnesota, Minneapolis, Minnesota, USA
| | - Matteo Biolatti
- Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy
| | - Valentina Dell'Oste
- Department of Public Health and Pediatric Sciences, University of Turin, Turin, Italy
| | - Craig J. Bierle
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Wade A. Bresnahan
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Reuben S. Harris
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
- Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, Texas, USA
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3
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Fanunza E, Cheng AZ, Auerbach AA, Stefanovska B, Moraes SN, Lokensgard JR, Biolatti M, Dell’Oste V, Bierle CJ, Bresnahan WA, Harris RS. Human cytomegalovirus mediates APOBEC3B relocalization early during infection through a ribonucleotide reductase-independent mechanism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.30.526383. [PMID: 36778493 PMCID: PMC9915650 DOI: 10.1101/2023.01.30.526383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The APOBEC3 family of DNA cytosine deaminases comprises an important arm of the innate antiviral defense system. The gamma-herpesviruses EBV and KSHV and the alpha-herpesviruses HSV-1 and HSV-2 have evolved an efficient mechanism to avoid APOBEC3 restriction by directly binding to APOBEC3B and facilitating its exclusion from the nuclear compartment. The only viral protein required for APOBEC3B relocalization is the large subunit of the ribonucleotide reductase (RNR). Here, we ask whether this APOBEC3B relocalization mechanism is conserved with the beta-herpesvirus human cytomegalovirus (HCMV). Although HCMV infection causes APOBEC3B relocalization from the nucleus to the cytoplasm in multiple cell types, the viral RNR (UL45) is not required. APOBEC3B relocalization occurs rapidly following infection suggesting involvement of an immediate early or early (IE-E) viral protein. In support of this mechanism, cycloheximide treatment of HCMV-infected cells prevents the expression of viral proteins and simultaneously blocks APOBEC3B relocalization. In comparison, the treatment of infected cells with phosphonoacetic acid, which is a viral DNA synthesis inhibitor affecting late protein expression, still permits A3B relocalization. These results combine to show that the beta-herpesvirus HCMV uses a fundamentally different, RNR-independent molecular mechanism to antagonize APOBEC3B. Importance Human cytomegalovirus (HCMV) infections can range from asymptomatic to severe, particularly in neonates and immunocompromised patients. HCMV has evolved strategies to overcome host-encoded antiviral defenses in order to achieve lytic viral DNA replication and dissemination and, under some conditions, latency and long-term persistence. Here, we show that HCMV infection causes the antiviral factor, APOBEC3B, to relocalize from the nuclear compartment to the cytoplasm. This overall strategy resembles that used by related herpesviruses. However, the HCMV relocalization mechanism utilizes a different viral factor(s) and available evidence suggests the involvement of at least one protein expressed at the early stages of infection. This knowledge is important because a greater understanding of this mechanism could lead to novel antiviral strategies that enable APOBEC3B to naturally restrict HCMV infection.
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Affiliation(s)
- Elisa Fanunza
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Adam Z. Cheng
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ashley A. Auerbach
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Bojana Stefanovska
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX 78229, USA
- Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Sofia N. Moraes
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - James R. Lokensgard
- Department of Medicine, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Matteo Biolatti
- Department of Public Health and Pediatric Sciences, University of Turin, Turin, 10126, Italy
| | - Valentina Dell’Oste
- Department of Public Health and Pediatric Sciences, University of Turin, Turin, 10126, Italy
| | - Craig J. Bierle
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Wade A. Bresnahan
- Department of Microbiology and Immunology, University of Minnesota, MN 55455, USA
| | - Reuben S. Harris
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX 78229, USA
- Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, TX 78229, USA
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4
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Berry N, Suspène R, Caval V, Khalfi P, Beauclair G, Rigaud S, Blanc H, Vignuzzi M, Wain-Hobson S, Vartanian JP. Herpes Simplex Virus Type 1 Infection Disturbs the Mitochondrial Network, Leading to Type I Interferon Production through the RNA Polymerase III/RIG-I Pathway. mBio 2021; 12:e0255721. [PMID: 34809467 PMCID: PMC8609356 DOI: 10.1128/mbio.02557-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 10/19/2021] [Indexed: 11/20/2022] Open
Abstract
Viruses have evolved a plethora of mechanisms to impair host innate immune responses. Herpes simplex virus type 1 (HSV-1), a double-stranded linear DNA virus, impairs the mitochondrial network and dynamics predominantly through the UL12.5 gene. We demonstrated that HSV-1 infection induced a remodeling of mitochondrial shape, resulting in a fragmentation of the mitochondria associated with a decrease in their volume and an increase in their sphericity. This damage leads to the release of mitochondrial DNA (mtDNA) to the cytosol. By generating a stable THP-1 cell line expressing the DNase I-mCherry fusion protein and a THP-1 cell line specifically depleted of mtDNA upon ethidium bromide treatment, we showed that cytosolic mtDNA contributes to type I interferon and APOBEC3A upregulation. This was confirmed by using an HSV-1 strain (KOS37 UL98-SPA) with a deletion of the UL12.5 gene that impaired its ability to induce mtDNA stress. Furthermore, by using an inhibitor of RNA polymerase III, we demonstrated that upon HSV-1 infection, cytosolic mtDNA enhanced type I interferon induction through the RNA polymerase III/RIG-I pathway. APOBEC3A was in turn induced by interferon. Deep sequencing analyses of cytosolic mtDNA mutations revealed an APOBEC3A signature predominantly in the 5'TpCpG context. These data demonstrate that upon HSV-1 infection, the mitochondrial network is disrupted, leading to the release of mtDNA and ultimately to its catabolism through APOBEC3-induced mutations. IMPORTANCE Herpes simplex virus 1 (HSV-1) impairs the mitochondrial network through the viral protein UL12.5. This leads to the fusion of mitochondria and simultaneous release of mitochondrial DNA (mtDNA) in a mouse model. We have shown that released mtDNA is recognized as a danger signal, capable of stimulating signaling pathways and inducing the production of proinflammatory cytokines. The expression of the human cytidine deaminase APOBEC3A is highly upregulated by interferon responses. This enzyme catalyzes the deamination of cytidine to uridine in single-stranded DNA substrates, resulting in the catabolism of edited DNA. Using human cell lines deprived of mtDNA and viral strains deficient in UL12, we demonstrated the implication of mtDNA in the production of interferon and APOBEC3A expression during viral infection. We have shown that HSV-1 induces mitochondrial network fragmentation in a human model and confirmed the implication of RNA polymerase III/RIG-I signaling in the capture of cytosolic mtDNA.
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Affiliation(s)
- Noémie Berry
- Molecular Retrovirology Unit, Institut Pasteur, Paris, France
- Sorbonne Université, Complexité du Vivant, Paris, France
| | | | - Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, Paris, France
| | - Pierre Khalfi
- Molecular Retrovirology Unit, Institut Pasteur, Paris, France
- Sorbonne Université, Complexité du Vivant, Paris, France
| | | | | | - Hervé Blanc
- Viral Populations and Pathogenesis Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
| | - Marco Vignuzzi
- Viral Populations and Pathogenesis Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
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5
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Law EK, Levin-Klein R, Jarvis MC, Kim H, Argyris PP, Carpenter MA, Starrett GJ, Temiz NA, Larson LK, Durfee C, Burns MB, Vogel RI, Stavrou S, Aguilera AN, Wagner S, Largaespada DA, Starr TK, Ross SR, Harris RS. APOBEC3A catalyzes mutation and drives carcinogenesis in vivo. J Exp Med 2021; 217:152061. [PMID: 32870257 PMCID: PMC7953736 DOI: 10.1084/jem.20200261] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 06/08/2020] [Accepted: 07/22/2020] [Indexed: 12/24/2022] Open
Abstract
The APOBEC3 family of antiviral DNA cytosine deaminases is implicated as the second largest source of mutation in cancer. This mutational process may be a causal driver or inconsequential passenger to the overall tumor phenotype. We show that human APOBEC3A expression in murine colon and liver tissues increases tumorigenesis. All other APOBEC3 family members, including APOBEC3B, fail to promote liver tumor formation. Tumor DNA sequences from APOBEC3A-expressing animals display hallmark APOBEC signature mutations in TCA/T motifs. Bioinformatic comparisons of the observed APOBEC3A mutation signature in murine tumors, previously reported APOBEC3A and APOBEC3B mutation signatures in yeast, and reanalyzed APOBEC mutation signatures in human tumor datasets support cause-and-effect relationships for APOBEC3A-catalyzed deamination and mutagenesis in driving multiple human cancers.
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Affiliation(s)
- Emily K Law
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Rena Levin-Klein
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Matthew C Jarvis
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Hyoung Kim
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Prokopios P Argyris
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN.,Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, MN
| | - Michael A Carpenter
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Gabriel J Starrett
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN.,Laboratory of Cellular Oncology, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Nuri A Temiz
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Health Informatics, University of Minnesota, Minneapolis, MN
| | - Lindsay K Larson
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Cameron Durfee
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
| | - Michael B Burns
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN.,Department of Biology, Loyola University, Chicago, IL
| | - Rachel I Vogel
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Department of Obstetrics, Gynecology, and Women's Health, University of Minnesota, Minneapolis, MN
| | - Spyridon Stavrou
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.,Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Alexya N Aguilera
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Sandra Wagner
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Department of Pediatrics, University of Minnesota, Minneapolis, MN
| | - David A Largaespada
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Department of Pediatrics, University of Minnesota, Minneapolis, MN
| | - Timothy K Starr
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Department of Obstetrics, Gynecology, and Women's Health, University of Minnesota, Minneapolis, MN
| | - Susan R Ross
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.,Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Reuben S Harris
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN.,Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN
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6
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Caval V, Jiao W, Berry N, Khalfi P, Pitré E, Thiers V, Vartanian JP, Wain-Hobson S, Suspène R. Mouse APOBEC1 cytidine deaminase can induce somatic mutations in chromosomal DNA. BMC Genomics 2019; 20:858. [PMID: 31726973 PMCID: PMC6854741 DOI: 10.1186/s12864-019-6216-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023] Open
Abstract
Background APOBEC1 (A1) enzymes are cytidine deaminases involved in RNA editing. In addition to this activity, a few A1 enzymes have been shown to be active on single stranded DNA. As two human ssDNA cytidine deaminases APOBEC3A (A3A), APOBEC3B (A3B) and related enzymes across the spectrum of placental mammals have been shown to introduce somatic mutations into nuclear DNA of cancer genomes, we explored the mutagenic threat of A1 cytidine deaminases to chromosomal DNA. Results Molecular cloning and expression of various A1 enzymes reveal that the cow, pig, dog, rabbit and mouse A1 have an intracellular ssDNA substrate specificity. However, among all the enzymes studied, mouse A1 appears to be singular, being able to introduce somatic mutations into nuclear DNA with a clear 5’TpC editing context, and to deaminate 5-methylcytidine substituted DNA which are characteristic features of the cancer related mammalian A3A and A3B enzymes. However, mouse A1 activity fails to elicit formation of double stranded DNA breaks, suggesting that mouse A1 possess an attenuated nuclear DNA mutator phenotype reminiscent of human A3B. Conclusions At an experimental level mouse APOBEC1 is remarkable among 12 mammalian A1 enzymes in that it represents a source of somatic mutations in mouse genome, potentially fueling oncogenesis. While the order Rodentia is bereft of A3A and A3B like enzymes it seems that APOBEC1 may well substitute for it, albeit remaining much less active. This modifies the paradigm that APOBEC3 and AID enzymes are the sole endogenous mutator enzymes giving rise to off-target editing of mammalian genomes.
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Affiliation(s)
- Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.
| | - Wenjuan Jiao
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Noémie Berry
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Pierre Khalfi
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Emmanuelle Pitré
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Valérie Thiers
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Jean-Pierre Vartanian
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Simon Wain-Hobson
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Rodolphe Suspène
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
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7
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Green AM, Weitzman MD. The spectrum of APOBEC3 activity: From anti-viral agents to anti-cancer opportunities. DNA Repair (Amst) 2019; 83:102700. [PMID: 31563041 PMCID: PMC6876854 DOI: 10.1016/j.dnarep.2019.102700] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 12/17/2022]
Abstract
The APOBEC3 family of cytosine deaminases are part of the innate immune response to viral infection, but also have the capacity to damage cellular DNA. Detection of mutational signatures consistent with APOBEC3 activity, together with elevated APOBEC3 expression in cancer cells, has raised the possibility that these enzymes contribute to oncogenesis. Genome deamination by APOBEC3 enzymes also elicits DNA damage response signaling and presents therapeutic vulnerabilities for cancer cells. Here, we discuss implications of APOBEC3 activity in cancer and the potential to exploit their mutagenic activity for targeted cancer therapies.
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Affiliation(s)
- Abby M Green
- Division of Oncology, Children's Hospital of Philadelphia, United States; Division of Infectious Diseases, Children's Hospital of Philadelphia, United States; Center for Childhood Cancer Research, Children's Hospital of Philadelphia, United States; Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, United States; Department of Pediatrics, Washington University School of Medicine, United States.
| | - Matthew D Weitzman
- Center for Childhood Cancer Research, Children's Hospital of Philadelphia, United States; Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, United States; Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, United States.
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8
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Wang D, Li X, Li J, Lu Y, Zhao S, Tang X, Chen X, Li J, Zheng Y, Li S, Sun R, Yan M, Yu D, Cao G, Yang Y. APOBEC3B interaction with PRC2 modulates microenvironment to promote HCC progression. Gut 2019; 68:1846-1857. [PMID: 31154396 DOI: 10.1136/gutjnl-2018-317601] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 04/22/2019] [Accepted: 05/12/2019] [Indexed: 12/20/2022]
Abstract
OBJECTIVE APOBEC3B (A3B), a cytidine deaminase acting as a contributor to the APOBEC mutation pattern in many kinds of tumours, is upregulated in patients with hepatocellular carcinoma (HCC). However, APOBEC mutation patterns are absent in HCC. The mechanism of how A3B affects HCC progression remains elusive. DESIGN A3B -promoter luciferase reporter and other techniques were applied to elucidate mechanisms of A3B upregulation in HCC. A3B overexpression and knockdown cell models, immunocompetent and immune-deficient mouse HCC model were conducted to investigate the influence of A3B on HCC progression. RNA-seq, flow cytometry and other techniques were conducted to analyse how A3B modulated the cytokine to enhance the recruitment of myeloid--derived suppressor cells (MDSCs) and tumour--associated macrophages (TAMs). RESULTS A3B upregulation through non-classical nuclear factor-κB (NF-κB)signalling promotes HCC growth in immunocompetent mice, associated with an increase of MDSCs, TAMs and programmed cell death1 (PD1) exprssed CD8+ T cells. A CCR2 antagonist suppressed TAMs and MDSCs infiltration and delayed tumour growth in A3B and A3BE68Q/E255Q- expressing mouse tumours. Mechanistically, A3B upregulation in HCC depresses global H3K27me3 abundance via interaction with polycomb repressor complex 2 (PRC2) and reduces an occupancy of H3K27me3 on promoters of the chemokine CCL2 to recruit massive TAMs and MDSCs. CONCLUSION Our observations uncover a deaminase-independent role of the A3B in modulating the HCC microenvironment and demonstrate a proof for the concept of targeting A3B in HCC immunotherapy.
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Affiliation(s)
- Duowei Wang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Xianjing Li
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Jiani Li
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Yuan Lu
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Sen Zhao
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Xinying Tang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Xin Chen
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Jiaying Li
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Yan Zheng
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Shuran Li
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Rui Sun
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Ming Yan
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Decai Yu
- Department of General Surgery, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China
| | - Guangwen Cao
- Department of Epidemiology, Second Military Medical University, Shanghai, China
| | - Yong Yang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
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9
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Brown WL, Law EK, Argyris PP, Carpenter MA, Levin-Klein R, Ranum AN, Molan AM, Forster CL, Anderson BD, Lackey L, Harris RS. A Rabbit Monoclonal Antibody against the Antiviral and Cancer Genomic DNA Mutating Enzyme APOBEC3B. Antibodies (Basel) 2019; 8:antib8030047. [PMID: 31544853 PMCID: PMC6783943 DOI: 10.3390/antib8030047] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 12/18/2022] Open
Abstract
The DNA cytosine deaminase APOBEC3B (A3B) is normally an antiviral factor in the innate immune response. However, A3B has been implicated in cancer mutagenesis, particularly in solid tumors of the bladder, breast, cervix, head/neck, and lung. Here, we report data on the generation and characterization of a rabbit monoclonal antibody (mAb) for human A3B. One mAb, 5210-87-13, demonstrates utility in multiple applications, including ELISA, immunoblot, immunofluorescence microscopy, and immunohistochemistry. In head-to-head tests with commercial reagents, 5210-87-13 was the only rabbit monoclonal suitable for detecting native A3B and for immunohistochemical quantification of A3B in tumor tissues. This novel mAb has the potential to enable a wide range of fundamental and clinical studies on A3B in human biology and disease.
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Affiliation(s)
- William L Brown
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Emily K Law
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Prokopios P Argyris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Michael A Carpenter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Rena Levin-Klein
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alison N Ranum
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Amy M Molan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Colleen L Forster
- Clinical and Translational Science Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Brett D Anderson
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Lela Lackey
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA.
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA.
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455, USA.
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10
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Buisson R, Langenbucher A, Bowen D, Kwan EE, Benes CH, Zou L, Lawrence MS. Passenger hotspot mutations in cancer driven by APOBEC3A and mesoscale genomic features. Science 2019; 364:eaaw2872. [PMID: 31249028 PMCID: PMC6731024 DOI: 10.1126/science.aaw2872] [Citation(s) in RCA: 186] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 05/23/2019] [Indexed: 12/12/2022]
Abstract
Cancer drivers require statistical modeling to distinguish them from passenger events, which accumulate during tumorigenesis but provide no fitness advantage to cancer cells. The discovery of driver genes and mutations relies on the assumption that exact positional recurrence is unlikely by chance; thus, the precise sharing of mutations across patients identifies drivers. Examining the mutation landscape in cancer genomes, we found that many recurrent cancer mutations previously designated as drivers are likely passengers. Our integrated bioinformatic and biochemical analyses revealed that these passenger hotspot mutations arise from the preference of APOBEC3A, a cytidine deaminase, for DNA stem-loops. Conversely, recurrent APOBEC-signature mutations not in stem-loops are enriched in well-characterized driver genes and may predict new drivers. This demonstrates that mesoscale genomic features need to be integrated into computational models aimed at identifying mutations linked to diseases.
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Affiliation(s)
- Rémi Buisson
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Department of Biological Chemistry, Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California, Irvine, CA, USA
| | - Adam Langenbucher
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
| | - Danae Bowen
- Department of Biological Chemistry, Center for Epigenetics and Metabolism, Chao Family Comprehensive Cancer Center, University of California, Irvine, CA, USA
| | - Eugene E Kwan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
| | - Cyril H Benes
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA.
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael S Lawrence
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA.
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
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11
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Li X, Caval V, Wain-Hobson S, Vartanian JP. Elephant APOBEC3A cytidine deaminase induces massive double-stranded DNA breaks and apoptosis. Sci Rep 2019; 9:728. [PMID: 30679716 PMCID: PMC6345769 DOI: 10.1038/s41598-018-37305-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 12/06/2018] [Indexed: 01/24/2023] Open
Abstract
The incidence of developing cancer should increase with the body mass, yet is not the case, a conundrum referred to as Peto’s paradox. Elephants have a lower incidence of cancer suggesting that these animals have probably evolved different ways to protect themselves against the disease. The paradox is worth revisiting with the realization that most mammals encode an endogenous APOBEC3 cytidine deaminase capable of mutating single stranded DNA. Indeed, the mutagenic activity of some APOBEC3 enzymes has been shown to introduce somatic mutations into genomic DNA. These enzymes are now recognized as causal agent responsible for the accumulation of CG- > TA transitions and DNA breaks leading to chromosomal rearrangements in human cancer genomes. Here, we identified an elephant A3Z1 gene, related to human APOBEC3A and showed that it could efficiently deaminate cytidine, 5-methylcytidine and produce DNA breaks leading to massive apoptosis, similar to other mammalian APOBEC3A enzymes where body mass varies by up to four orders of magnitude. Consequently, it could be considered that eAZ1 might contribute to cancer in elephants in a manner similar to their proposed role in humans. If so, eAZ1 might be particularly well regulated to counter Peto’s paradox.
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Affiliation(s)
- Xiongxiong Li
- Molecular Retrovirology Unit, Institut Pasteur, CNRS-URA 3015, 28 rue du Docteur Roux, 75724, Paris, France.,Lanzhou Institute of Biological Products Co., Ltd (LIBP), subsidiary company of China National Biotec Group Company Limited (CNBG), 730046, Lanzhou, China
| | - Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, CNRS-URA 3015, 28 rue du Docteur Roux, 75724, Paris, France
| | - Simon Wain-Hobson
- Molecular Retrovirology Unit, Institut Pasteur, CNRS-URA 3015, 28 rue du Docteur Roux, 75724, Paris, France
| | - Jean-Pierre Vartanian
- Molecular Retrovirology Unit, Institut Pasteur, CNRS-URA 3015, 28 rue du Docteur Roux, 75724, Paris, France.
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12
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Salter JD, Polevoda B, Bennett RP, Smith HC. Regulation of Antiviral Innate Immunity Through APOBEC Ribonucleoprotein Complexes. Subcell Biochem 2019; 93:193-219. [PMID: 31939152 DOI: 10.1007/978-3-030-28151-9_6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The DNA mutagenic enzyme known as APOBEC3G (A3G) plays a critical role in innate immunity to Human Immunodeficiency Virus-1 (HIV-1 ). A3G is a zinc-dependent enzyme that mutates select deoxycytidines (dC) to deoxyuridine (dU) through deamination within nascent single stranded DNA (ssDNA) during HIV reverse transcription. This activity requires that the enzyme be delivered to viral replication complexes by redistributing from the cytoplasm of infected cells to budding virions through what appears to be an RNA-dependent process. Once inside infected cells, A3G must bind to nascent ssDNA reverse transcripts for dC to dU base modification gene editing. In this chapter we will discuss data indicating that ssDNA deaminase activity of A3G is regulated by RNA binding to A3G and ribonucleoprotein complex formation along with evidence suggesting that RNA-selective interactions with A3G are temporally and mechanistically important in this process.
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Affiliation(s)
- Jason D Salter
- OyaGen, Inc, 77 Ridgeland Road, Rochester, NY, 14623, USA
| | - Bogdan Polevoda
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, 601 Elmwood Ave, Rochester, NY, 14642, USA
| | - Ryan P Bennett
- OyaGen, Inc, 77 Ridgeland Road, Rochester, NY, 14623, USA
| | - Harold C Smith
- OyaGen, Inc, 77 Ridgeland Road, Rochester, NY, 14623, USA. .,Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, 601 Elmwood Ave, Rochester, NY, 14642, USA.
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13
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Hou S, Silvas TV, Leidner F, Nalivaika EA, Matsuo H, Kurt Yilmaz N, Schiffer CA. Structural Analysis of the Active Site and DNA Binding of Human Cytidine Deaminase APOBEC3B. J Chem Theory Comput 2018; 15:637-647. [PMID: 30457868 DOI: 10.1021/acs.jctc.8b00545] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
APOBEC3 (A3) proteins, a family of human cytidine deaminases, protect the host from endogenous retro-elements and exogenous viral infections by introducing hypermutations. However, overexpressed A3s can modify genomic DNA to promote tumorigenesis, especially A3B. Despite their overall similarity, A3 proteins have distinct deamination activity. Recently determined A3 structures have revealed the molecular determinants of nucleotide specificity and DNA binding. However, for A3B, the structural basis for regulation of deamination activity and the role of active site loops in coordinating DNA had remained unknown. Using advanced molecular modeling followed by experimental mutational analysis and dynamics simulations, we investigated the molecular mechanism of DNA binding by A3B-CTD. We modeled fully native A3B-DNA structure, and we identified Arg211 in loop 1 as the gatekeeper coordinating DNA and critical residue for nucleotide specificity. We also identified a unique autoinhibited conformation in A3B-CTD that restricts access and binding of DNA to the active site. Our results reveal the structural basis for DNA binding and relatively lower catalytic activity of A3B and provide opportunities for rational design of specific inhibitors to benefit cancer therapeutics.
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Affiliation(s)
- Shurong Hou
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
| | - Tania V Silvas
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
| | - Florian Leidner
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
| | - Ellen A Nalivaika
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
| | - Hiroshi Matsuo
- Basic Research Laboratory, Leidos Biomedical Research, Inc. , Frederick National Laboratory for Cancer Research , Frederick , Maryland 21702 , United States
| | - Nese Kurt Yilmaz
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
| | - Celia A Schiffer
- Department of Biochemistry and Molecular Pharmacology , University of Massachusetts Medical School , Worcester , Massachusetts 01655 , United States
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14
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Laude HC, Caval V, Bouzidi MS, Li X, Jamet F, Henry M, Suspène R, Wain-Hobson S, Vartanian JP. The rabbit as an orthologous small animal model for APOBEC3A oncogenesis. Oncotarget 2018; 9:27809-27822. [PMID: 29963239 PMCID: PMC6021247 DOI: 10.18632/oncotarget.25593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 05/24/2018] [Indexed: 11/25/2022] Open
Abstract
APOBEC3 are cytidine deaminases that convert cytidine to uridine residues. APOBEC3A and APOBEC3B enzymes able to target genomic DNA are involved in oncogenesis of a sizeable proportion of human cancers. While the APOBEC3 locus is conserved in mammals, it encodes from 1–7 genes. APOBEC3A is conserved in most mammals, although absent in pigs, cats and throughout Rodentia whereas APOBEC3B is restricted to the Primate order. Here we show that the rabbit APOBEC3 locus encodes two genes of which APOBEC3A enzyme is strictly orthologous to human APOBEC3A. The rabbit enzyme is expressed in the nucleus and the cytoplasm, it can deaminate cytidine, 5-methcytidine residues, nuclear DNA and induce double-strand DNA breaks. The rabbit APOBEC3A enzyme is negatively regulated by the rabbit TRIB3 pseudokinase protein which is guardian of genome integrity, just like its human counterpart. This indicates that the APOBEC3A/TRIB3 pair is conserved over approximately 100 million years. The rabbit APOBEC3A gene is widely expressed in rabbit tissues, unlike human APOBEC3A. These data demonstrate that rabbit could be used as a small animal model for studying APOBEC3 driven oncogenesis.
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Affiliation(s)
- Hélène C Laude
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Mohamed S Bouzidi
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Xiongxiong Li
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France.,Lanzhou Institute of Biological Products Co., Ltd (LIBP), subsidiary company of China National Biotec Group Company Limited (CNBG), Lanzhou 730046, China
| | - Florence Jamet
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Michel Henry
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Rodolphe Suspène
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
| | - Simon Wain-Hobson
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, France
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15
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Salter JD, Smith HC. Modeling the Embrace of a Mutator: APOBEC Selection of Nucleic Acid Ligands. Trends Biochem Sci 2018; 43:606-622. [PMID: 29803538 PMCID: PMC6073885 DOI: 10.1016/j.tibs.2018.04.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/25/2018] [Accepted: 04/30/2018] [Indexed: 12/17/2022]
Abstract
The 11-member APOBEC (apolipoprotein B mRNA editing catalytic polypeptide-like) family of zinc-dependent cytidine deaminases bind to RNA and single-stranded DNA (ssDNA) and, in specific contexts, modify select (deoxy)cytidines to (deoxy)uridines. In this review, we describe advances made through high-resolution co-crystal structures of APOBECs bound to mono- or oligonucleotides that reveal potential substrate-specific binding sites at the active site and non-sequence-specific nucleic acid binding sites distal to the active site. We also discuss the effect of APOBEC oligomerization on functionality. Future structural studies will need to address how ssDNA binding away from the active site may enhance catalysis and the mechanism by which RNA binding may modulate catalytic activity on ssDNA. APOBEC proteins catalyze deamination of cytidine or deoxycytidine in either a sequence-specific or semi-specific manner on either DNA or RNA. APOBECs each possess the cytidine deaminase core fold, but sequence and structural differences among loops surrounding the zinc-dependent active site impart differences in sequence-dependent target preferences, binding affinity, catalytic rate, and regulation of substrate access to the active site among the 11 family members. APOBECs also regulate the deamination reaction through additional nucleic acid substrate binding sites located within surface grooves or patches of positive electrostatic potential that are distal to the active site but may do so nonspecifically. Binding of nonsubstrate RNA and RNA-mediated oligomerization by APOBECs that deaminate ssDNA downregulates catalytic activity but also controls APOBEC subcellular or virion localization. The presence of a second, though noncatalytic, cytidine deaminase domain for some APOBECs and the ability of some APOBECs to oligomerize add additional molecular surfaces for positive or negative regulation of catalysis through nucleic acid binding.
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Affiliation(s)
- Jason D Salter
- OyaGen, Inc., 77 Ridgeland Road, Rochester, NY 14623, USA.
| | - Harold C Smith
- OyaGen, Inc., 77 Ridgeland Road, Rochester, NY 14623, USA; University of Rochester, School of Medicine and Dentistry, Department of Biochemistry and Biophysics, 601 Elmwood Avenue, Rochester, NY 14642, USA.
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16
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Shi K, Demir Ö, Carpenter MA, Wagner J, Kurahashi K, Harris RS, Amaro RE, Aihara H. Conformational Switch Regulates the DNA Cytosine Deaminase Activity of Human APOBEC3B. Sci Rep 2017; 7:17415. [PMID: 29234087 PMCID: PMC5727031 DOI: 10.1038/s41598-017-17694-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 11/29/2017] [Indexed: 02/07/2023] Open
Abstract
The APOBEC3B (A3B) single-stranded DNA (ssDNA) cytosine deaminase has important roles in innate immunity but is also a major endogenous source of mutations in cancer. Previous structural studies showed that the C-terminal catalytic domain of human A3B has a tightly closed active site, and rearrangement of the surrounding loops is required for binding to substrate ssDNA. Here we report structures of the A3B catalytic domain in a new crystal form that show alternative, yet still closed, conformations of active site loops. All-atom molecular dynamics simulations support the dynamic behavior of active site loops and recapitulate the distinct modes of interactions that maintain a closed active site. Replacing segments of A3B loop 1 to mimic the more potent cytoplasmic deaminase APOBEC3A leads to elevated ssDNA deaminase activity, likely by facilitating opening of the active site. These data collectively suggest that conformational equilibrium of the A3B active site loops, skewed toward being closed, controls enzymatic activity by regulating binding to ssDNA substrates.
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Affiliation(s)
- Ke Shi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Özlem Demir
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Michael A Carpenter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Jeff Wagner
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Kayo Kurahashi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, 55455, USA.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, 55455, USA
| | - Rommie E Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Hideki Aihara
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, 55455, USA. .,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, 55455, USA. .,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, 55455, USA.
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17
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APOBEC3A Is Upregulated by Human Cytomegalovirus (HCMV) in the Maternal-Fetal Interface, Acting as an Innate Anti-HCMV Effector. J Virol 2017; 91:JVI.01296-17. [PMID: 28956761 DOI: 10.1128/jvi.01296-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/18/2017] [Indexed: 12/14/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the leading cause of congenital infection and is associated with a wide range of neurodevelopmental disabilities and intrauterine growth restriction. Yet our current understanding of the mechanisms modulating transplacental HCMV transmission is poor. The placenta, given its critical function in protecting the fetus, has evolved effective yet largely uncharacterized innate immune barriers against invading pathogens. Here we show that the intrinsic cellular restriction factor apolipoprotein B editing catalytic subunit-like 3A (APOBEC3A [A3A]) is profoundly upregulated following ex vivo HCMV infection in human decidual tissues-constituting the maternal aspect of the placenta. We directly demonstrated that A3A severely restricted HCMV replication upon controlled overexpression in epithelial cells, acting by a cytidine deamination mechanism to introduce hypermutations into the viral genome. Importantly, we further found that A3 editing of HCMV DNA occurs both ex vivo in HCMV-infected decidual organ cultures and in vivo in amniotic fluid samples obtained during natural congenital infection. Our results reveal a previously unexplored role for A3A as an innate anti-HCMV effector, activated by HCMV infection in the maternal-fetal interface. These findings pave the way to new insights into the potential impact of APOBEC proteins on HCMV pathogenesis.IMPORTANCE In view of the grave outcomes associated with congenital HCMV infection, there is an urgent need to better understand the innate mechanisms acting to limit transplacental viral transmission. Toward this goal, our findings reveal the role of the intrinsic cellular restriction factor A3A (which has never before been studied in the context of HCMV infection and vertical viral transmission) as a potent anti-HCMV innate barrier, activated by HCMV infection in the authentic tissues of the maternal-fetal interface. The detection of naturally occurring hypermutations in clinical amniotic fluid samples of congenitally infected fetuses further supports the idea of the occurrence of A3 editing of the viral genome in the setting of congenital HCMV infection. Given the widely differential tissue distribution characteristics and biological functions of the members of the A3 protein family, our findings should pave the way to future studies examining the potential impact of A3A as well as of other A3s on HCMV pathogenesis.
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18
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Xiao X, Yang H, Arutiunian V, Fang Y, Besse G, Morimoto C, Zirkle B, Chen XS. Structural determinants of APOBEC3B non-catalytic domain for molecular assembly and catalytic regulation. Nucleic Acids Res 2017; 45:7494-7506. [PMID: 28575276 PMCID: PMC5499559 DOI: 10.1093/nar/gkx362] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 05/27/2017] [Indexed: 12/26/2022] Open
Abstract
The catalytic activity of human cytidine deaminase APOBEC3B (A3B) has been correlated with kataegic mutational patterns within multiple cancer types. The molecular basis of how the N-terminal non-catalytic CD1 regulates the catalytic activity and consequently, biological function of A3B remains relatively unknown. Here, we report the crystal structure of a soluble human A3B-CD1 variant and delineate several structural elements of CD1 involved in molecular assembly, nucleic acid interactions and catalytic regulation of A3B. We show that (i) A3B expressed in human cells exists in hypoactive high-molecular-weight (HMW) complexes, which can be activated without apparent dissociation into low-molecular-weight (LMW) species after RNase A treatment. (ii) Multiple surface hydrophobic residues of CD1 mediate the HMW complex assembly and affect the catalytic activity, including one tryptophan residue W127 that likely acts through regulating nucleic acid binding. (iii) One of the highly positively charged surfaces on CD1 is involved in RNA-dependent attenuation of A3B catalysis. (iv) Surface hydrophobic residues of CD1 are involved in heterogeneous nuclear ribonucleoproteins (hnRNPs) binding to A3B. The structural and biochemical insights described here suggest that unique structural features on CD1 regulate the molecular assembly and catalytic activity of A3B through distinct mechanisms.
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Affiliation(s)
- Xiao Xiao
- Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- These authors contributed equally to this work as first authors
| | - Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- These authors contributed equally to this work as first authors
| | - Vagan Arutiunian
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
| | - Yao Fang
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- Department of Clinical Microbiology and Immunology of Southwest Hospital, Third Military Medical University, Chongqing 400038, China
- 161 Hospital, Wuhan 430012, China
| | - Guillaume Besse
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- Polytech' Clermont-Ferrand, Université Blaise Pascal, Clermont-Ferrand, France
| | - Cherie Morimoto
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
| | - Brett Zirkle
- Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
| | - Xiaojiang S. Chen
- Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, University of Southern California, Los Angeles, CA 90089, USA
- Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089, USA
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
- To whom correspondence should be addressed. Tel: +1 213 740 5487; Fax: +1 213 740 4340;
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19
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Chen Z, Eggerman TL, Bocharov AV, Baranova IN, Vishnyakova TG, Kurlander R, Patterson AP. Heat shock proteins stimulate APOBEC-3-mediated cytidine deamination in the hepatitis B virus. J Biol Chem 2017. [PMID: 28637869 DOI: 10.1074/jbc.m116.760637] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Apolipoprotein B mRNA-editing enzyme catalytic subunit 3 (APOBEC-3) enzymes are cytidine deaminases that are broadly and constitutively expressed. They are often up-regulated during carcinogenesis and candidate genes for causing the major single-base substitution in cancer-associated DNA mutations. Moreover, APOBEC-3s are involved in host innate immunity against many viruses. However, how APOBEC-3 mutational activity is regulated in normal and pathological conditions remains largely unknown. Heat shock protein levels are often elevated in both carcinogenesis and viral infection and are associated with DNA mutations. Here, using mutational analyses of hepatitis B virus (HBV), we found that Hsp90 stimulates deamination activity of APOBEC-3G (A3G), A3B, and A3C during co-expression in human liver HepG2 cells. Hsp90 directly stimulated A3G deamination activity when the purified proteins were used in in vitro reactions. Hsp40, -60, and -70 also had variable stimulatory effects in the cellular assay, but not in vitro Sequencing analyses further demonstrated that Hsp90 increased both A3G cytosine mutation efficiency on HBV DNA and total HBV mutation frequency. In addition, Hsp90 shifted A3G's cytosine region selection in HBV DNA and increased A3G's 5' nucleoside preference for deoxycytidine (5'-CC). Furthermore, the Hsp90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin dose dependently inhibited A3G and A3B mutational activity on HBV viral DNA. Hsp90 knockdown by siRNA or by Hsp90 active-site mutation also decreased A3G activity. These results indicate that heat shock proteins, in particular Hsp90, stimulate APOBEC-3-mediated DNA deamination activity, suggesting a potential physiological role in carcinogenesis and viral innate immunity.
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Affiliation(s)
- Zhigang Chen
- From the Department of Laboratory Medicine, Clinical Center
| | - Thomas L Eggerman
- From the Department of Laboratory Medicine, Clinical Center.,the Division of Diabetes, Endocrinology, and Metabolic Diseases, NIDDK, and
| | | | | | | | | | - Amy P Patterson
- From the Department of Laboratory Medicine, Clinical Center, .,NHLBI, National Institutes of Health, Bethesda, Maryland 20892
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20
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Suspène R, Mussil B, Laude H, Caval V, Berry N, Bouzidi MS, Thiers V, Wain-Hobson S, Vartanian JP. Self-cytoplasmic DNA upregulates the mutator enzyme APOBEC3A leading to chromosomal DNA damage. Nucleic Acids Res 2017; 45:3231-3241. [PMID: 28100701 PMCID: PMC5389686 DOI: 10.1093/nar/gkx001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 12/29/2016] [Accepted: 01/02/2017] [Indexed: 12/23/2022] Open
Abstract
Foreign and self-cytoplasmic DNA are recognized by numerous DNA sensor molecules leading to the production of type I interferons. Such DNA agonists should be degraded otherwise cells would be chronically stressed. Most human APOBEC3 cytidine deaminases can initiate catabolism of cytoplasmic mitochondrial DNA. Using the human myeloid cell line THP-1 with an interferon inducible APOBEC3A gene, we show that cytoplasmic DNA triggers interferon α and β production through the RNA polymerase III transcription/RIG-I pathway leading to massive upregulation of APOBEC3A. By catalyzing C→U editing in single stranded DNA fragments, the enzyme prevents them from re-annealing so attenuating the danger signal. The price to pay is chromosomal DNA damage in the form of CG→TA mutations and double stranded DNA breaks which, in the context of chronic inflammation, could drive cells down the path toward cancer.
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Affiliation(s)
- Rodolphe Suspène
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Bianka Mussil
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
- Unit of Infection Models, German Primate Centre, Kellnerweg 4, 37077 Goettingen, Germany
| | - Hélène Laude
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Noémie Berry
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Mohamed S. Bouzidi
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Valérie Thiers
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Simon Wain-Hobson
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
| | - Jean-Pierre Vartanian
- Molecular Retrovirology Unit, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris cedex 15, France
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21
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Shi K, Carpenter M, Banerjee S, Shaban N, Kurahashi K, Salamango D, McCann J, Starrett G, Duffy J, Demir Ö, Amaro R, Harki D, Harris R, Aihara H. Structural basis for targeted DNA cytosine deamination and mutagenesis by APOBEC3A and APOBEC3B. Nat Struct Mol Biol 2017; 24:131-139. [PMID: 27991903 PMCID: PMC5296220 DOI: 10.1038/nsmb.3344] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/16/2016] [Indexed: 12/17/2022]
Abstract
APOBEC-catalyzed cytosine-to-uracil deamination of single-stranded DNA (ssDNA) has beneficial functions in immunity and detrimental effects in cancer. APOBEC enzymes have intrinsic dinucleotide specificities that impart hallmark mutation signatures. Although numerous structures have been solved, mechanisms for global ssDNA recognition and local target-sequence selection remain unclear. Here we report crystal structures of human APOBEC3A and a chimera of human APOBEC3B and APOBEC3A bound to ssDNA at 3.1-Å and 1.7-Å resolution, respectively. These structures reveal a U-shaped DNA conformation, with the specificity-conferring -1 thymine flipped out and the target cytosine inserted deep into the zinc-coordinating active site pocket. The -1 thymine base fits into a groove between flexible loops and makes direct hydrogen bonds with the protein, accounting for the strong 5'-TC preference. These findings explain both conserved and unique properties among APOBEC family members, and they provide a basis for the rational design of inhibitors to impede the evolvability of viruses and tumors.
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Affiliation(s)
- K. Shi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - M.A. Carpenter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - S. Banerjee
- Northeastern Collaborative Access Team, Cornell University, Advanced Photon Source, Lemont, Illinois, USA, 60439
| | - N.M. Shaban
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - K. Kurahashi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - D.J. Salamango
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - J.L. McCann
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - G.J. Starrett
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - J.V. Duffy
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - Ö. Demir
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093
| | - R.E. Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093
| | - D.A. Harki
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - R.S. Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, USA, 55455
| | - H. Aihara
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA, 55455
- Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota, USA, 55455
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22
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Radmanesh H, Spethmann T, Enßen J, Schürmann P, Bhuju S, Geffers R, Antonenkova N, Khusnutdinova E, Sadr-Nabavi A, Shandiz FH, Park-Simon TW, Hillemanns P, Christiansen H, Bogdanova N, Dörk T. Assessment of an APOBEC3B truncating mutation, c.783delG, in patients with breast cancer. Breast Cancer Res Treat 2017; 162:31-37. [PMID: 28062980 DOI: 10.1007/s10549-016-4100-9] [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: 09/23/2016] [Accepted: 12/30/2016] [Indexed: 12/30/2022]
Abstract
PURPOSE APOBEC3B belongs to the family of DNA-editing enzymes. A copy number variant targeting the genomic APOBEC3A-APOBEC3B locus has a significant impact on breast cancer risk, but the relative contribution of APOBEC3B is uncertain. In this study, we investigate a loss-of-function mutation that selectively targets APOBEC3B, for its association with breast cancer risk. METHODS We performed exome sequencing on genomic DNA samples of 6 Byelorussian patients with familial breast cancer. We then studied through mutation-specific genotyping four hospital-based breast cancer case-control series from Belarus, Russia, Germany, and Iran, respectively, comprising a total of 3070 breast cancer patients and 2878 healthy females. Results were evaluated using fixed-effects meta-analyses. RESULTS Exome sequencing uncovered a frameshift mutation, APOBEC3B*c.783delG, that was recurrent in the study populations. Subsequent genotyping identified this mutation in 23 additional breast cancer cases and 9 healthy female controls, with an adjusted Odds Ratio 2.29 (95% CI 1.04; 5.03, P = 0.04) in the combined analysis. There was an enrichment of the c.783delG mutation in patients with breast cancer diagnosed below 50 years of age (OR 3.22, 95% CI 1.37; 7.56, P = 0.007). CONCLUSIONS APOBEC3B*c.783delG showed evidence of modest association with breast cancer and seemed to contribute to earlier onset of the disease. These results may need to be reconciled with proposals to consider APOBEC3B as a possible therapeutic target in breast cancer.
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Affiliation(s)
- Hoda Radmanesh
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany
| | - Tessa Spethmann
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany.,Radiation Oncology Research Unit, Hannover Medical School, Hannover, Germany
| | - Julia Enßen
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany
| | - Peter Schürmann
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany
| | - Sabin Bhuju
- Genome Analytics Unit, Helmholtz Center for Infection Research, Brunswick, Germany
| | - Robert Geffers
- Genome Analytics Unit, Helmholtz Center for Infection Research, Brunswick, Germany
| | - Natalia Antonenkova
- N.N. Alexandrov Research Institute of Oncology and Medical Radiology, Minsk, Belarus
| | - Elza Khusnutdinova
- Institute of Biochemistry and Genetics, Ufa Science Center, Ufa, Russia.,Department of Genetics and Fundamental Medicine, Bashkir State University, Ufa, Russia
| | - Ariane Sadr-Nabavi
- Medical Genetic Research Center (MGRC), School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Molecular Medicine Research Group, Academic Centers for EducationCulture and Research (ACECR), Khorasan Basavi Branch, Mashhad, Iran.,Department of Medical Genetics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Fatemeh Homaei Shandiz
- Radiation Oncology Cancer Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Tjoung-Won Park-Simon
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany
| | - Peter Hillemanns
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany
| | - Hans Christiansen
- Radiation Oncology Research Unit, Hannover Medical School, Hannover, Germany
| | - Natalia Bogdanova
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany.,Radiation Oncology Research Unit, Hannover Medical School, Hannover, Germany
| | - Thilo Dörk
- Gynaecology Research Unit, Clinics of Obstetrics and Gynaecology, Hannover Medical School, Hannover, Germany.
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23
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Kostrzak A, Caval V, Escande M, Pliquet E, Thalmensi J, Bestetti T, Julithe M, Fiette L, Huet T, Wain-Hobson S, Langlade-Demoyen P. APOBEC3A intratumoral DNA electroporation in mice. Gene Ther 2016; 24:74-83. [PMID: 27858943 DOI: 10.1038/gt.2016.77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 10/26/2016] [Accepted: 11/11/2016] [Indexed: 12/21/2022]
Abstract
Human APOBEC3A (A3A) cytidine deaminase shows pro-apoptotic properties resulting from hypermutation of genomic DNA, induction of double-stranded DNA breaks (DSBs) and G1 cell cycle arrest. Given this, we evaluated the antitumor efficacy of A3A by intratumoral electroporation of an A3A expression plasmid. DNA was repeatedly electroporated into B16OVA, B16Luc tumors of C57BL/6J mice as well as the aggressive fibrosarcoma Sarc2 tumor of HLA-A*0201/DRB1*0101 transgenic mice using noninvasive plate electrodes. Intratumoral electroporation of A3A plasmid DNA resulted in regression of ~50% of small B16OVA melanoma tumors that did not rebound in the following 2 months without treatment. Larger or more aggressive tumors escaped regression when so treated. As APOBEC3A was much less efficient in provoking hypermutation and DSBs in B16OVA cells compared with human or quail cells, it is likely that APOBEC3A would be more efficient in a human setting than in a mouse model.
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Affiliation(s)
- A Kostrzak
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - V Caval
- Molecular Retrovirology Unit, Institut Pasteur, Paris, France
| | - M Escande
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - E Pliquet
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - J Thalmensi
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - T Bestetti
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - M Julithe
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - L Fiette
- Human Histopathology and Animal Models, Infection & Epidemiology Department, Institut Pasteur, Paris, France.,Université Paris Descartes, Sorbonne Paris-Cité, Paris, France
| | - T Huet
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France
| | - S Wain-Hobson
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France.,Molecular Retrovirology Unit, Institut Pasteur, Paris, France
| | - P Langlade-Demoyen
- Invectys, Pepinière Paris Biotech Santé Cochin, Paris, France.,Molecular Retrovirology Unit, Institut Pasteur, Paris, France
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24
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Starrett GJ, Luengas EM, McCann JL, Ebrahimi D, Temiz NA, Love RP, Feng Y, Adolph MB, Chelico L, Law EK, Carpenter MA, Harris RS. The DNA cytosine deaminase APOBEC3H haplotype I likely contributes to breast and lung cancer mutagenesis. Nat Commun 2016; 7:12918. [PMID: 27650891 PMCID: PMC5036005 DOI: 10.1038/ncomms12918] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 08/16/2016] [Indexed: 12/17/2022] Open
Abstract
Cytosine mutations within TCA/T motifs are common in cancer. A likely cause is the DNA cytosine deaminase APOBEC3B (A3B). However, A3B-null breast tumours still have this mutational bias. Here we show that APOBEC3H haplotype I (A3H-I) provides a likely solution to this paradox. A3B-null tumours with this mutational bias have at least one copy of A3H-I despite little genetic linkage between these genes. Although deemed inactive previously, A3H-I has robust activity in biochemical and cellular assays, similar to A3H-II after compensation for lower protein expression levels. Gly105 in A3H-I (versus Arg105 in A3H-II) results in lower protein expression levels and increased nuclear localization, providing a mechanism for accessing genomic DNA. A3H-I also associates with clonal TCA/T-biased mutations in lung adenocarcinoma suggesting this enzyme makes broader contributions to cancer mutagenesis. These studies combine to suggest that A3B and A3H-I, together, explain the bulk of ‘APOBEC signature' mutations in cancer. The APOBEC family of enzymes are cytidine deaminases with APOBEC3A and APOBEC3B thought to contribute to DNA damage signatures detected in cancer genomes. Here, the authors demonstrate an unappreciated role for APOBEC3H haplotype I in the generation of DNA damage in breast cancer.
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Affiliation(s)
- Gabriel J Starrett
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Elizabeth M Luengas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Jennifer L McCann
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Diako Ebrahimi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Nuri A Temiz
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Robin P Love
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E5
| | - Yuqing Feng
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E5
| | - Madison B Adolph
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E5
| | - Linda Chelico
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E5
| | - Emily K Law
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Michael A Carpenter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Center for Genome Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA
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25
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Shaban NM, Shi K, Li M, Aihara H, Harris RS. 1.92 Angstrom Zinc-Free APOBEC3F Catalytic Domain Crystal Structure. J Mol Biol 2016; 428:2307-2316. [PMID: 27139641 PMCID: PMC5142242 DOI: 10.1016/j.jmb.2016.04.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 04/13/2016] [Accepted: 04/19/2016] [Indexed: 01/07/2023]
Abstract
The APOBEC3 family of DNA cytosine deaminases is capable of restricting the replication of HIV-1 and other pathogens. Here, we report a 1.92 Å resolution crystal structure of the Vif-binding and catalytic domain of APOBEC3F (A3F). This structure is distinct from the previously published APOBEC and phylogenetically related deaminase structures, as it is the first without zinc in the active site. We determined an additional structure containing zinc in the same crystal form that allows direct comparison with the zinc-free structure. In the absence of zinc, the conserved active site residues that normally participate in zinc coordination show unique conformations, including a 90 degree rotation of His249 and disulfide bond formation between Cys280 and Cys283. We found that zinc coordination is influenced by pH, and treating the protein at low pH in crystallization buffer is sufficient to remove zinc. Zinc coordination and catalytic activity are reconstituted with the addition of zinc only in a reduced environment likely due to the two active site cysteines readily forming a disulfide bond when not coordinating zinc. We show that the enzyme is active in the presence of zinc and cobalt but not with other divalent metals. These results unexpectedly demonstrate that zinc is not required for the structural integrity of A3F and suggest that metal coordination may be a strategy for regulating the activity of A3F and related deaminases.
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Affiliation(s)
- Nadine M. Shaban
- Department of Biochemistry, Molecular Biology, and Biophysics, Masonic Cancer Center, Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455,Correspondence: ;
| | - Ke Shi
- Department of Biochemistry, Molecular Biology, and Biophysics, Masonic Cancer Center, Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455
| | - Ming Li
- Department of Biochemistry, Molecular Biology, and Biophysics, Masonic Cancer Center, Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455
| | - Hideki Aihara
- Department of Biochemistry, Molecular Biology, and Biophysics, Masonic Cancer Center, Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455
| | - Reuben S. Harris
- Department of Biochemistry, Molecular Biology, and Biophysics, Masonic Cancer Center, Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455,Correspondence: ;
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26
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Byeon IJL, Byeon CH, Wu T, Mitra M, Singer D, Levin JG, Gronenborn AM. Nuclear Magnetic Resonance Structure of the APOBEC3B Catalytic Domain: Structural Basis for Substrate Binding and DNA Deaminase Activity. Biochemistry 2016; 55:2944-59. [PMID: 27163633 DOI: 10.1021/acs.biochem.6b00382] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Human APOBEC3B (A3B) is a member of the APOBEC3 (A3) family of cytidine deaminases, which function as DNA mutators and restrict viral pathogens and endogenous retrotransposons. Recently, A3B was identified as a major source of genetic heterogeneity in several human cancers. Here, we determined the solution nuclear magnetic resonance structure of the catalytically active C-terminal domain (CTD) of A3B and performed detailed analyses of its deaminase activity. The core of the structure comprises a central five-stranded β-sheet with six surrounding helices, common to all A3 proteins. The structural fold is most similar to that of A3A and A3G-CTD, with the most prominent difference being found in loop 1. The catalytic activity of A3B-CTD is ∼15-fold lower than that of A3A, although both exhibit a similar pH dependence. Interestingly, A3B-CTD with an A3A loop 1 substitution had significantly increased deaminase activity, while a single-residue change (H29R) in A3A loop 1 reduced A3A activity to the level seen with A3B-CTD. This establishes that loop 1 plays an important role in A3-catalyzed deamination by precisely positioning the deamination-targeted C into the active site. Overall, our data provide important insights into the determinants of the activities of individual A3 proteins and facilitate understanding of their biological function.
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Affiliation(s)
| | | | - Tiyun Wu
- Section on Viral Gene Regulation, Program in Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Mithun Mitra
- Section on Viral Gene Regulation, Program in Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Dustin Singer
- Section on Viral Gene Regulation, Program in Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Judith G Levin
- Section on Viral Gene Regulation, Program in Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health , Bethesda, Maryland 20892, United States
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