1
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Butt Y, Sakhtemani R, Mohamad-Ramshan R, Lawrence MS, Bhagwat AS. Distinguishing preferences of human APOBEC3A and APOBEC3B for cytosines in hairpin loops, and reflection of these preferences in APOBEC-signature cancer genome mutations. Nat Commun 2024; 15:2369. [PMID: 38499553 PMCID: PMC10948833 DOI: 10.1038/s41467-024-46231-w] [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: 07/31/2023] [Accepted: 02/19/2024] [Indexed: 03/20/2024] Open
Abstract
The APOBEC3 enzymes convert cytosines in single-stranded DNA to uracils to protect against viruses and retrotransposons but can contribute to mutations that diversify tumors. To understand the mechanism of mutagenesis, we map the uracils resulting from expression of APOBEC3B or its catalytic carboxy-terminal domain (CTD) in Escherichia coli. Like APOBEC3A, the uracilomes of A3B and A3B-CTD show a preference to deaminate cytosines near transcription start sites and the lagging-strand replication templates and in hairpin loops. Both biochemical activities of the enzymes and genomic uracil distribution show that A3A prefers 3 nt loops the best, while A3B prefers 4 nt loops. Reanalysis of hairpin loop mutations in human tumors finds intrinsic characteristics of both the enzymes, with a much stronger contribution from A3A. We apply Hairpin Signatures 1 and 2, which define A3A and A3B preferences respectively and are orthogonal to published methods, to evaluate their contribution to human tumor mutations.
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Affiliation(s)
- Yasha Butt
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - Ramin Sakhtemani
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
- Massachusetts General Hospital Cancer Center, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Michael S Lawrence
- Massachusetts General Hospital Cancer Center, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Ashok S Bhagwat
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
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2
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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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Butt Y, Sakhtemani R, Mohamad-Ramshan R, Lawrence MS, Bhagwat AS. Distinguishing preferences of human APOBEC3A and APOBEC3B for cytosines in hairpin loops, and reflection of these preferences in APOBEC-signature cancer genome mutations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.01.551518. [PMID: 37577595 PMCID: PMC10418155 DOI: 10.1101/2023.08.01.551518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The APOBEC3 family of enzymes convert cytosines in single-stranded DNA to uracils thereby causing mutations. These enzymes protect human cells against viruses and retrotransposons, but in many cancers they contribute to mutations that diversify the tumors and help them escape anticancer drug treatments. To understand the mechanism of mutagenesis by APOBEC3B, we expressed the complete enzyme or its catalytic carboxy-terminal domain (CTD) in repair-deficient Eschericia coli and mapped the resulting uracils using uracil pull-down and sequencing technology. The uracilomes of A3B-full and A3B-CTD showed peaks in many of the same regions where APOBEC3A also created uracilation peaks. Like A3A, the two A3B enzymes also preferred to deaminate cytosines near transcription start sites and in the lagging-strand template at replication forks. In contrast to an earlier report that A3B does not favor hairpin loops over linear DNA, we found that both A3B-full and A3B-CTD showed a strong preference for cytosines in hairpin loops. The major difference between A3A and A3B was that while the former enzyme prefers 3 nt loops the best, A3B prefers loops of 4 nt over those of other lengths. Furthermore, within 5 nt loops, A3A prefers cytosine to be in the penultimate position, while A3B prefers it to be at the 3' end of the loop. We confirmed these loop size and sequence preferences experimentally using purified A3A and A3B-CTD proteins. Reanalysis of hairpin loop mutations in human tumors using the size, sequence and position preferences of the two enzymes found that the tumors displayed mutations with intrinsic characteristics of both the enzymes with a stronger contribution from A3A.
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4
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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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5
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Moraes SN, Becker JT, Moghadasi SA, Shaban NM, Auerbach AA, Cheng AZ, Harris RS. Evidence linking APOBEC3B genesis and evolution of innate immune antagonism by gamma-herpesvirus ribonucleotide reductases. eLife 2022; 11:83893. [PMID: 36458685 DOI: 10.7554/elife.83893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 10/12/2022] [Indexed: 12/04/2022] Open
Abstract
Viruses have evolved diverse mechanisms to antagonize host immunity such as direct inhibition and relocalization of cellular APOBEC3B (A3B) by the ribonucleotide reductase (RNR) of Epstein-Barr virus. Here, we investigate the mechanistic conservation and evolutionary origin of this innate immune counteraction strategy. First, we find that human gamma-herpesvirus RNRs engage A3B via largely distinct surfaces. Second, we show that RNR-mediated enzymatic inhibition and relocalization of A3B depend upon binding to different regions of the catalytic domain. Third, we show that the capability of viral RNRs to antagonize A3B is conserved among gamma-herpesviruses that infect humans and Old World monkeys that encode this enzyme but absent in homologous viruses that infect New World monkeys that naturally lack the A3B gene. Finally, we reconstruct the ancestral primate A3B protein and demonstrate that it is active and similarly engaged by the RNRs from viruses that infect humans and Old World monkeys but not by the RNRs from viruses that infect New World monkeys. These results combine to indicate that the birth of A3B at a critical branchpoint in primate evolution may have been a driving force in selecting for an ancestral gamma-herpesvirus with an expanded RNR functionality through counteraction of this antiviral enzyme.
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Affiliation(s)
- Sofia N Moraes
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States
| | - Jordan T Becker
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States
| | - Seyed Arad Moghadasi
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States
| | - Nadine M Shaban
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States
| | - Ashley A Auerbach
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States.,Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, United States
| | - Adam Z Cheng
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, United States.,Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, United States.,Howard Hughes Medical Institute, University of Texas Health San Antonio, San Antonio, United States
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6
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Wong L, Sami A, Chelico L. Competition for DNA binding between the genome protector replication protein A and the genome modifying APOBEC3 single-stranded DNA deaminases. Nucleic Acids Res 2022; 50:12039-12057. [PMID: 36444883 PMCID: PMC9757055 DOI: 10.1093/nar/gkac1121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/21/2022] [Accepted: 11/08/2022] [Indexed: 11/30/2022] Open
Abstract
The human APOBEC family of eleven cytosine deaminases use RNA and single-stranded DNA (ssDNA) as substrates to deaminate cytosine to uracil. This deamination event has roles in lipid metabolism by altering mRNA coding, adaptive immunity by causing evolution of antibody genes, and innate immunity through inactivation of viral genomes. These benefits come at a cost where some family members, primarily from the APOBEC3 subfamily (APOBEC3A-H, excluding E), can cause off-target deaminations of cytosine to form uracil on transiently single-stranded genomic DNA, which induces mutations that are associated with cancer evolution. Since uracil is only promutagenic, the mutations observed in cancer genomes originate only when uracil is not removed by uracil DNA glycosylase (UNG) or when the UNG-induced abasic site is erroneously repaired. However, when ssDNA is present, replication protein A (RPA) binds and protects the DNA from nucleases or recruits DNA repair proteins, such as UNG. Thus, APOBEC enzymes must compete with RPA to access their substrate. Certain APOBEC enzymes can displace RPA, bind and scan ssDNA efficiently to search for cytosines, and can become highly overexpressed in tumor cells. Depending on the DNA replication conditions and DNA structure, RPA can either be in excess or deficient. Here we discuss the interplay between these factors and how despite RPA, multiple cancer genomes have a mutation bias at cytosines indicative of APOBEC activity.
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Affiliation(s)
- Lai Wong
- University of Saskatchewan, College of Medicine, Department of Biochemistry, Microbiology, and Immunology, Saskatoon, Saskatchewan, S7N 5E5, Canada
| | - Alina Sami
- University of Saskatchewan, College of Medicine, Department of Biochemistry, Microbiology, and Immunology, Saskatoon, Saskatchewan, S7N 5E5, Canada
| | - Linda Chelico
- To whom correspondence should be addressed. Tel: +1 306 966 4318; Fax: +1 306 966 4298;
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7
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G 1/S Cell Cycle Induction by Epstein-Barr Virus BORF2 Is Mediated by P53 and APOBEC3B. J Virol 2022; 96:e0066022. [PMID: 36069545 PMCID: PMC9517719 DOI: 10.1128/jvi.00660-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Herpesvirus lytic infection causes cells to arrest at the G1/S phase of the cell cycle by poorly defined mechanisms. In a prior study using fluorescent ubiquitination-based cell cycle indicator (FUCCI) cells that express fluorescently tagged proteins marking different stages of the cell cycle, we showed that the Epstein-Barr virus (EBV) protein BORF2 induces the accumulation of G1/S cells, and that BORF2 affects p53 levels without affecting the p53 target protein p21. We also found that BORF2 specifically interacted with APOBEC3B (A3B) and forms perinuclear bodies with A3B that prevent A3B from mutating replicating EBV genomes. We now show that BORF2 also interacts with p53 and that A3B interferes with the BORF2-p53 interaction, although A3B and p53 engage distinct surfaces on BORF2. Cell cycle analysis showed that G1/S induction by BORF2 is abrogated when either p53 or A3B is silenced or when an A3B-binding mutant of BORF2 is used. Furthermore, silencing A3B in EBV lytic infection increased cell proliferation, supporting a role for A3B in G1/S arrest. These data suggest that the p53 induced by BORF2 is inactive when it binds BORF2, but is released and induces G1/S arrest when A3B is present and sequesters BORF2 in perinuclear bodies. Interestingly, this mechanism is conserved in the BORF2 homologue in HSV-1, which also re-localizes A3B, induces and binds p53, and induces G1/S dependent on A3B and p53. In summary, we have identified a new mechanism by which G1/S arrest can be induced in herpesvirus lytic infection. IMPORTANCE In lytic infection, herpesviruses cause cells to arrest at the G1/S phase of the cell cycle in order to provide an optimal environment for viral replication; however, the mechanisms involved are not well understood. We have shown that the Epstein-Barr virus BORF2 protein and its homologue in herpes simplex virus 1 both induce G1/S, and do this by similar mechanisms which involve binding p53 and APOBEC3B and induction of p53. Our study identifies a new mechanism by which G1/S arrest can be induced in herpesvirus lytic infection and a new role of APOBEC3B in herpesvirus lytic infection.
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8
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Shaban NM, Yan R, Shi K, Moraes SN, Cheng AZ, Carpenter MA, McLellan JS, Yu Z, Harris RS. Cryo-EM structure of the EBV ribonucleotide reductase BORF2 and mechanism of APOBEC3B inhibition. SCIENCE ADVANCES 2022; 8:eabm2827. [PMID: 35476445 PMCID: PMC9045721 DOI: 10.1126/sciadv.abm2827] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 02/23/2022] [Indexed: 05/26/2023]
Abstract
Viruses use a plethora of mechanisms to evade immune responses. A recent example is neutralization of the nuclear DNA cytosine deaminase APOBEC3B by the Epstein-Barr virus (EBV) ribonucleotide reductase subunit BORF2. Cryo-EM studies of APOBEC3B-BORF2 complexes reveal a large >1000-Å2 binding surface composed of multiple structural elements from each protein, which effectively blocks the APOBEC3B active site from accessing single-stranded DNA substrates. Evolutionary optimization is suggested by unique insertions in BORF2 absent from other ribonucleotide reductases and preferential binding to APOBEC3B relative to the highly related APOBEC3A and APOBEC3G enzymes. A molecular understanding of this pathogen-host interaction has potential to inform the development of drugs that block the interaction and liberate the natural antiviral activity of APOBEC3B. In addition, given a role for APOBEC3B in cancer mutagenesis, it may also be possible for information from the interaction to be used to develop DNA deaminase inhibitors.
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Affiliation(s)
- Nadine M. Shaban
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Rui Yan
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 55416, USA
| | - Ke Shi
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sofia N. Moraes
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Adam Z. Cheng
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Michael A. Carpenter
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55416, USA
| | - Jason S. McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Zhiheng Yu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 55416, USA
| | - Reuben S. Harris
- Department of Biochemistry, Molecular Biology, and Biophysics, Institute for Molecular Virology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55416, USA
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9
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Chen Y, Luo L, Deng L, Tian X, Chen S, Xu A, Yuan S. New Insights Into the Lineage-Specific Expansion and Functional Diversification of Lamprey AID/APOBEC Family. Front Immunol 2022; 13:822616. [PMID: 35359986 PMCID: PMC8962628 DOI: 10.3389/fimmu.2022.822616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
The AID/APOBEC family which converts cytidine to uridine on RNA or DNA experienced dynamic expansion in primates in order to resist exogenous viruses and endogenous retrotransposons. Recently, expansion of AID/APOBEC-like homologs has also been observed in the extant jawless vertebrate lamprey. To reveal what causes such expansion and leads to the functional diversification of lamprey cytosine deaminases (CDAs), we reassessed the CDA genes in Lethenteron japonicum (Lj). We first confirmed the expansion of LjCDA1L1 (CDA1-like 1) genes and found the expression correlation of LjCDA2 and LjCDA1L2 with LjVLRs (variable lymphocyte receptors). Among up to 14 LjCDA1L1 proteins, LjCDA1L1_4a has an extremely high deamination activity on ssDNA and buDNA and, unexpectedly, on dsDNA. LjCDA1L1s can also restrict the infection of HSV-1 particles. Thus, the arms race between the host and pathogens along with the recruitment by VLR assembly may participate together to form a driving force in the expansion and diversification of the lamprey AID/APOBEC family.
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Affiliation(s)
- Yan Chen
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Lingjie Luo
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Lisi Deng
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Xiaoxue Tian
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Shangwu Chen
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Anlong Xu
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing, China
- *Correspondence: Shaochun Yuan, ; Anlong Xu,
| | - Shaochun Yuan
- Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Laboratory of Ocean Science and Engineering (Zhuhai), State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- *Correspondence: Shaochun Yuan, ; Anlong Xu,
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10
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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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11
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Sadeghpour S, Khodaee S, Rahnama M, Rahimi H, Ebrahimi D. Human APOBEC3 Variations and Viral Infection. Viruses 2021; 13:1366. [PMID: 34372572 PMCID: PMC8310219 DOI: 10.3390/v13071366] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022] Open
Abstract
Human APOBEC3 (apolipoprotein B mRNA-editing catalytic polypeptide-like 3) enzymes are capable of inhibiting a wide range of endogenous and exogenous viruses using deaminase and deaminase-independent mechanisms. These enzymes are essential components of our innate immune system, as evidenced by (a) their strong positive selection and expansion in primates, (b) the evolution of viral counter-defense mechanisms, such as proteasomal degradation mediated by HIV Vif, and (c) hypermutation and inactivation of a large number of integrated HIV-1 proviruses. Numerous APOBEC3 single nucleotide polymorphisms, haplotypes, and splice variants have been identified in humans. Several of these variants have been reported to be associated with differential antiviral immunity. This review focuses on the current knowledge in the field about these natural variations and their roles in infectious diseases.
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Affiliation(s)
- Shiva Sadeghpour
- Department of Biological Science, University of California Irvine, Irvine, CA 92697, USA;
| | - Saeideh Khodaee
- Department of Bioinformatics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran 1417614335, Iran;
| | - Mostafa Rahnama
- Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA;
| | - Hamzeh Rahimi
- Department of Molecular Medicine, Biotechnology Research Center, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Diako Ebrahimi
- Texas Biomedical Research Institute, San Antonio, TX 78227, USA
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12
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Cheng AZ, Moraes SN, Shaban NM, Fanunza E, Bierle CJ, Southern PJ, Bresnahan WA, Rice SA, Harris RS. APOBECs and Herpesviruses. Viruses 2021; 13:v13030390. [PMID: 33671095 PMCID: PMC7998176 DOI: 10.3390/v13030390] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/26/2021] [Accepted: 02/27/2021] [Indexed: 12/14/2022] Open
Abstract
The apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) family of DNA cytosine deaminases provides a broad and overlapping defense against viral infections. Successful viral pathogens, by definition, have evolved strategies to escape restriction by the APOBEC enzymes of their hosts. HIV-1 and related retroviruses are thought to be the predominant natural substrates of APOBEC enzymes due to obligate single-stranded (ss)DNA replication intermediates, abundant evidence for cDNA strand C-to-U editing (genomic strand G-to-A hypermutation), and a potent APOBEC degradation mechanism. In contrast, much lower mutation rates are observed in double-stranded DNA herpesviruses and the evidence for APOBEC mutation has been less compelling. However, recent work has revealed that Epstein-Barr virus (EBV), Kaposi’s sarcoma-associated herpesvirus (KSHV), and herpes simplex virus-1 (HSV-1) are potential substrates for cellular APOBEC enzymes. To prevent APOBEC-mediated restriction these viruses have repurposed their ribonucleotide reductase (RNR) large subunits to directly bind, inhibit, and relocalize at least two distinct APOBEC enzymes—APOBEC3B and APOBEC3A. The importance of this interaction is evidenced by genetic inactivation of the EBV RNR (BORF2), which results in lower viral infectivity and higher levels of C/G-to-T/A hypermutation. This RNR-mediated mechanism therefore likely functions to protect lytic phase viral DNA replication intermediates from APOBEC-catalyzed DNA C-to-U deamination. The RNR-APOBEC interaction defines a new pathogen-host conflict that the virus must win in real-time for transmission and pathogenesis. However, partial losses over evolutionary time may also benefit the virus by providing mutational fuel for adaptation.
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Affiliation(s)
- Adam Z. Cheng
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; (S.N.M.); (N.M.S.); (E.F.)
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Correspondence: (A.Z.C.); (R.S.H.)
| | - Sofia N. Moraes
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; (S.N.M.); (N.M.S.); (E.F.)
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Nadine M. Shaban
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; (S.N.M.); (N.M.S.); (E.F.)
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Elisa Fanunza
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; (S.N.M.); (N.M.S.); (E.F.)
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Craig J. Bierle
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Peter J. Southern
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Wade A. Bresnahan
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stephen A. Rice
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Reuben S. Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; (S.N.M.); (N.M.S.); (E.F.)
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; (C.J.B.); (P.J.S.); (W.A.B.); (S.A.R.)
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455, USA
- Correspondence: (A.Z.C.); (R.S.H.)
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13
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Uriu K, Kosugi Y, Ito J, Sato K. The Battle between Retroviruses and APOBEC3 Genes: Its Past and Present. Viruses 2021; 13:124. [PMID: 33477360 PMCID: PMC7830460 DOI: 10.3390/v13010124] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/07/2021] [Accepted: 01/13/2021] [Indexed: 12/17/2022] Open
Abstract
The APOBEC3 family of proteins in mammals consists of cellular cytosine deaminases and well-known restriction factors against retroviruses, including lentiviruses. APOBEC3 genes are highly amplified and diversified in mammals, suggesting that their evolution and diversification have been driven by conflicts with ancient viruses. At present, lentiviruses, including HIV, the causative agent of AIDS, are known to encode a viral protein called Vif to overcome the antiviral effects of the APOBEC3 proteins of their hosts. Recent studies have revealed that the acquisition of an anti-APOBEC3 ability by lentiviruses is a key step in achieving successful cross-species transmission. Here, we summarize the current knowledge of the interplay between mammalian APOBEC3 proteins and viral infections and introduce a scenario of the coevolution of mammalian APOBEC3 genes and viruses.
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Affiliation(s)
- Keiya Uriu
- Division of Systems Virology, Department of Infectious Disease Control, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo 1088639, Japan; (K.U.); (J.I.)
- Graduate School of Medicine, The University of Tokyo, Tokyo 1130033, Japan
| | - Yusuke Kosugi
- Laboratory of Systems Virology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 6068507, Japan;
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 6068501, Japan
| | - Jumpei Ito
- Division of Systems Virology, Department of Infectious Disease Control, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo 1088639, Japan; (K.U.); (J.I.)
| | - Kei Sato
- Division of Systems Virology, Department of Infectious Disease Control, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo 1088639, Japan; (K.U.); (J.I.)
- Graduate School of Medicine, The University of Tokyo, Tokyo 1130033, Japan
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14
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Stewart JA, Schauer G, Bhagwat AS. Visualization of uracils created by APOBEC3A using UdgX shows colocalization with RPA at stalled replication forks. Nucleic Acids Res 2020; 48:e118. [PMID: 33074285 PMCID: PMC7672425 DOI: 10.1093/nar/gkaa845] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 09/11/2020] [Accepted: 09/18/2020] [Indexed: 12/19/2022] Open
Abstract
The AID/APOBEC enzymes deaminate cytosines in single-stranded DNA (ssDNA) and play key roles in innate and adaptive immunity. The resulting uracils cause mutations and strand breaks that inactivate viruses and diversify antibody repertoire. Mutational evidence suggests that two members of this family, APOBEC3A (A3A) and APOBEC3B, deaminate cytosines in the lagging-strand template during replication. To obtain direct evidence for the presence of these uracils, we engineered a protein that covalently links to DNA at uracils, UdgX, for mammalian expression and immunohistochemistry. We show that UdgX strongly prefers uracils in ssDNA over those in U•G or U:A pairs, and localizes to nuclei in a dispersed form. When A3A is expressed in these cells, UdgX tends to form foci. The treatment of cells with cisplatin, which blocks replication, causes a significant increase in UdgX foci. Furthermore, this protein- and hence the uracils created by A3A- colocalize with replication protein A (RPA), but not with A3A. Using purified proteins, we confirm that RPA inhibits A3A by binding ssDNA, but despite its overexpression following cisplatin treatment, RPA is unable to fully protect ssDNA created by cisplatin adducts. This suggests that cisplatin treatment of cells expressing APOBEC3A should cause accumulation of APOBEC signature mutations.
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Affiliation(s)
- Jessica A Stewart
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA
| | - Grant Schauer
- Department of Biochemistry & Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Ashok S Bhagwat
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.,Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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15
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Zhang Z, Perković M, Gu Q, Balakrishnan K, Sangwiman A, Häussinger D, Lindemann D, Münk C. HIV-2 Vif and foamy virus Bet antagonize APOBEC3B by different mechanisms. Virology 2020; 554:17-27. [PMID: 33333348 DOI: 10.1016/j.virol.2020.11.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 11/17/2022]
Abstract
The family of human APOBEC3 (A3) restriction factors is formed by seven different proteins, A3A-D and A3F-H. Among these A3s, A3B harbors strong restriction activity against several retroviruses, such as SIV, and MLV. How lentiviruses and other retroviruses, prevalent in many primate species, counteract A3B is poorly understood. In this study, we found that A3B strongly inhibited SIVmac and HIV-2 infectivity, which was antagonized by their Vif proteins. Both SIVmac and HIV-2 Vifs diminished the protein level of A3B in viral producer cells, and hindered A3B incorporation into viral particles. We observed that HIV-2 Vif binds A3B and induces its degradation by assembly of an A3-Vif-CUL5-ElonginB/C E3-ligase complex. A3B and HIV-2 Vif localize and interact in the nucleus. In addition, we also found that the accessory protein Bet of prototype foamy virus (PFV) significantly antagonized the anti-SIVmac activity of A3B. Like Vif, Bet prevented the incorporation of A3B into viral particles. However, in contrast to Vif Bet did not induce the degradation of A3B. Rather, Bet binds A3B to block formation of high molecular weight A3B complexes and induces A3B cytoplasmic trapping. In summary, these findings indicate that A3B is recognized by diverse retroviruses and counteracted by virus-specific pathways that could be targeted to inhibit A3B mutating activity in cancers.
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Affiliation(s)
- Zeli Zhang
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Mario Perković
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Qinyong Gu
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Kannan Balakrishnan
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anucha Sangwiman
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Dirk Lindemann
- Institute of Virology, Medical Faculty "Carl Gustav Carus", Technische Universität Dresden, 01307, Dresden, Germany; CRTD/DFG-Center for Regenerative Therapies, Technische Universität Dresden, 01307, Dresden, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.
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16
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Abstract
APOBEC3 (A3) genes are members of the AID/APOBEC gene family that are found exclusively in mammals. A3 genes encode antiviral proteins that restrict the replication of retroviruses by inducing G-to-A mutations in their genomes and have undergone extensive amplification and diversification during mammalian evolution. Endogenous retroviruses (ERVs) are sequences derived from ancient retroviruses that are widespread mammalian genomes. In this study we characterize the A3 repertoire and use the ERV fossil record to explore the long-term history of coevolutionary interaction between A3s and retroviruses. We examine the genomes of 160 mammalian species and identify 1,420 AID/APOBEC-related genes, including representatives of previously uncharacterized lineages. We show that A3 genes have been amplified in mammals and that amplification is positively correlated with the extent of germline colonization by ERVs. Moreover, we demonstrate that the signatures of A3-mediated mutation can be detected in ERVs found throughout mammalian genomes and show that in mammalian species with expanded A3 repertoires, ERVs are significantly enriched for G-to-A mutations. Finally, we show that A3 amplification occurred concurrently with prominent ERV invasions in primates. Our findings establish that conflict with retroviruses is a major driving force for the rapid evolution of mammalian A3 genes.
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