1
|
Begum MSTM, Bokani A, Rajib SA, Soleimanpour M, Maeda Y, Yoshimura K, Satou Y, Ebrahimi D, Ikeda T. Potential Role of APOBEC3 Family Proteins in SARS-CoV-2 Replication. Viruses 2024; 16:1141. [PMID: 39066304 PMCID: PMC11281575 DOI: 10.3390/v16071141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/12/2024] [Accepted: 07/13/2024] [Indexed: 07/28/2024] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has acquired multiple mutations since its emergence. Analyses of the SARS-CoV-2 genomes from infected patients exhibit a bias toward C-to-U mutations, which are suggested to be caused by the apolipoprotein B mRNA editing enzyme polypeptide-like 3 (APOBEC3, A3) cytosine deaminase proteins. However, the role of A3 enzymes in SARS-CoV-2 replication remains unclear. To address this question, we investigated the effect of A3 family proteins on SARS-CoV-2 replication in the myeloid leukemia cell line THP-1 lacking A3A to A3G genes. The Wuhan, BA.1, and BA.5 variants had comparable viral replication in parent and A3A-to-A3G-null THP-1 cells stably expressing angiotensin-converting enzyme 2 (ACE2) protein. On the other hand, the replication and infectivity of these variants were abolished in A3A-to-A3G-null THP-1-ACE2 cells in a series of passage experiments over 20 days. In contrast to previous reports, we observed no evidence of A3-induced SARS-CoV-2 mutagenesis in the passage experiments. Furthermore, our analysis of a large number of publicly available SARS-CoV-2 genomes did not reveal conclusive evidence for A3-induced mutagenesis. Our studies suggest that A3 family proteins can positively contribute to SARS-CoV-2 replication; however, this effect is deaminase-independent.
Collapse
Affiliation(s)
- MST Monira Begum
- Division of Molecular Virology and Genetics, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-0811, Japan
| | - Ayub Bokani
- School of Engineering and Technology, CQ University, Sydney, NSW 2000, Australia
| | - Samiul Alam Rajib
- Division of Genomics and Transcriptomics, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-0811, Japan
| | | | - Yosuke Maeda
- Department of Microbiology, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
- Department of Nursing, Kibi International University, Takahashi 716-8508, Japan
| | | | - Yorifumi Satou
- Division of Genomics and Transcriptomics, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-0811, Japan
| | - Diako Ebrahimi
- Texas Biomedical Research Institute, San Antonio, TX 78227, USA
| | - Terumasa Ikeda
- Division of Molecular Virology and Genetics, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-0811, Japan
| |
Collapse
|
2
|
Hu Y, Delviks-Frankenberry KA, Wu C, Arizaga F, Pathak VK, Xiong Y. Structural insights into PPP2R5A degradation by HIV-1 Vif. Nat Struct Mol Biol 2024:10.1038/s41594-024-01314-6. [PMID: 38789685 DOI: 10.1038/s41594-024-01314-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 04/11/2024] [Indexed: 05/26/2024]
Abstract
HIV-1 Vif recruits host cullin-RING-E3 ubiquitin ligase and CBFβ to degrade the cellular APOBEC3 antiviral proteins through diverse interactions. Recent evidence has shown that Vif also degrades the regulatory subunits PPP2R5(A-E) of cellular protein phosphatase 2A to induce G2/M cell cycle arrest. As PPP2R5 proteins bear no functional or structural resemblance to A3s, it is unclear how Vif can recognize different sets of proteins. Here we report the cryogenic-electron microscopy structure of PPP2R5A in complex with HIV-1 Vif-CBFβ-elongin B-elongin C at 3.58 Å resolution. The structure shows PPP2R5A binds across the Vif molecule, with biochemical and cellular studies confirming a distinct Vif-PPP2R5A interface that partially overlaps with those for A3s. Vif also blocks a canonical PPP2R5A substrate-binding site, indicating that it suppresses the phosphatase activities through both degradation-dependent and degradation-independent mechanisms. Our work identifies critical Vif motifs regulating the recognition of diverse A3 and PPP2R5A substrates, whereby disruption of these host-virus protein interactions could serve as potential targets for HIV-1 therapeutics.
Collapse
Affiliation(s)
- Yingxia Hu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Krista A Delviks-Frankenberry
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, USA
| | - Chunxiang Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Fidel Arizaga
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vinay K Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, USA.
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| |
Collapse
|
3
|
Jang GM, Annan Sudarsan AK, Shayeganmehr A, Prando Munhoz E, Lao R, Gaba A, Granadillo Rodríguez M, Love RP, Polacco BJ, Zhou Y, Krogan NJ, Kaake RM, Chelico L. Protein Interaction Map of APOBEC3 Enzyme Family Reveals Deamination-Independent Role in Cellular Function. Mol Cell Proteomics 2024; 23:100755. [PMID: 38548018 PMCID: PMC11070599 DOI: 10.1016/j.mcpro.2024.100755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 03/13/2024] [Accepted: 03/25/2024] [Indexed: 04/09/2024] Open
Abstract
Human APOBEC3 enzymes are a family of single-stranded (ss)DNA and RNA cytidine deaminases that act as part of the intrinsic immunity against viruses and retroelements. These enzymes deaminate cytosine to form uracil which can functionally inactivate or cause degradation of viral or retroelement genomes. In addition, APOBEC3s have deamination-independent antiviral activity through protein and nucleic acid interactions. If expression levels are misregulated, some APOBEC3 enzymes can access the human genome leading to deamination and mutagenesis, contributing to cancer initiation and evolution. While APOBEC3 enzymes are known to interact with large ribonucleoprotein complexes, the function and RNA dependence are not entirely understood. To further understand their cellular roles, we determined by affinity purification mass spectrometry (AP-MS) the protein interaction network for the human APOBEC3 enzymes and mapped a diverse set of protein-protein and protein-RNA mediated interactions. Our analysis identified novel RNA-mediated interactions between APOBEC3C, APOBEC3H Haplotype I and II, and APOBEC3G with spliceosome proteins, and APOBEC3G and APOBEC3H Haplotype I with proteins involved in tRNA methylation and ncRNA export from the nucleus. In addition, we identified RNA-independent protein-protein interactions with APOBEC3B, APOBEC3D, and APOBEC3F and the prefoldin family of protein-folding chaperones. Interaction between prefoldin 5 (PFD5) and APOBEC3B disrupted the ability of PFD5 to induce degradation of the oncogene cMyc, implicating the APOBEC3B protein interaction network in cancer. Altogether, the results uncover novel functions and interactions of the APOBEC3 family and suggest they may have fundamental roles in cellular RNA biology, their protein-protein interactions are not redundant, and there are protein-protein interactions with tumor suppressors, suggesting a role in cancer biology. Data are available via ProteomeXchange with the identifier PXD044275.
Collapse
Affiliation(s)
- Gwendolyn M Jang
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Arun Kumar Annan Sudarsan
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Arzhang Shayeganmehr
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Erika Prando Munhoz
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Reanna Lao
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Amit Gaba
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Milaid Granadillo Rodríguez
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Robin P Love
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Benjamin J Polacco
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA
| | - Yuan Zhou
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA
| | - Robyn M Kaake
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, California, USA; J. David Gladstone Institutes, Gladstone Institute for Data Science and Biotechnology, San Francisco, California, USA.
| | - Linda Chelico
- College of Medicine, Biochemistry, Microbiology & Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
| |
Collapse
|
4
|
Yang H, Pacheco J, Kim K, Ebrahimi D, Ito F, Chen XS. Molecular mechanism for regulating APOBEC3G DNA editing function by the non-catalytic domain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.11.584510. [PMID: 38559028 PMCID: PMC10980023 DOI: 10.1101/2024.03.11.584510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
APOBEC3G (A3G) belongs to the AID/APOBEC cytidine deaminase family and is essential for antiviral immunity. It contains two zinc-coordinated cytidine-deaminase (CD) domains. The N-terminal CD1 domain is non-catalytic but has a strong affinity for nucleic acids, whereas the C-terminal CD2 domain catalyzes C-to-U editing in single-stranded DNA. The interplay between the two domains in DNA binding and editing is not fully understood. Here, our studies on rhesus macaque A3G (rA3G) show that the DNA editing function in linear and hairpin loop DNA is greatly enhanced by AA or GA dinucleotide motifs present downstream (in the 3'-direction) but not upstream (in the 5'-direction) of the target-C editing sites. The effective distance between AA/GA and the target-C sites depends on the local DNA secondary structure. We present two co-crystal structures of rA3G bound to ssDNA containing AA and GA, revealing the contribution of the non-catalytic CD1 domain in capturing AA/GA DNA and explaining our biochemical observations. Our structural and biochemical findings elucidate the molecular mechanism underlying the cooperative function between the non-catalytic and the catalytic domains of A3G, which is critical for its antiviral role and its contribution to genome mutations in cancer.
Collapse
Affiliation(s)
- Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Josue Pacheco
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Kyumin Kim
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Diako Ebrahimi
- Texas Biomedical Research Institute, San Antonio, TX 78227, USA
| | - Fumiaki Ito
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA90095, USA
| | - Xiaojiang S. Chen
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
- Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
- Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089, USA
| |
Collapse
|
5
|
Jang GM, Sudarsan AKA, Shayeganmehr A, Munhoz EP, Lao R, Gaba A, Rodríguez MG, Love RP, Polacco BJ, Zhou Y, Krogan NJ, Kaake RM, Chelico L. Protein interaction map of APOBEC3 enzyme family reveals deamination-independent role in cellular function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.06.579137. [PMID: 38370690 PMCID: PMC10871184 DOI: 10.1101/2024.02.06.579137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Human APOBEC3 enzymes are a family of single-stranded (ss)DNA and RNA cytidine deaminases that act as part of the intrinsic immunity against viruses and retroelements. These enzymes deaminate cytosine to form uracil which can functionally inactivate or cause degradation of viral or retroelement genomes. In addition, APOBEC3s have deamination independent antiviral activity through protein and nucleic acid interactions. If expression levels are misregulated, some APOBEC3 enzymes can access the human genome leading to deamination and mutagenesis, contributing to cancer initiation and evolution. While APOBEC3 enzymes are known to interact with large ribonucleoprotein complexes, the function and RNA dependence is not entirely understood. To further understand their cellular roles, we determined by affinity purification mass spectrometry (AP-MS) the protein interaction network for the human APOBEC3 enzymes and map a diverse set of protein-protein and protein-RNA mediated interactions. Our analysis identified novel RNA-mediated interactions between APOBEC3C, APOBEC3H Haplotype I and II, and APOBEC3G with spliceosome proteins, and APOBEC3G and APOBEC3H Haplotype I with proteins involved in tRNA methylation and ncRNA export from the nucleus. In addition, we identified RNA-independent protein-protein interactions with APOBEC3B, APOBEC3D, and APOBEC3F and the prefoldin family of protein folding chaperones. Interaction between prefoldin 5 (PFD5) and APOBEC3B disrupted the ability of PFD5 to induce degradation of the oncogene cMyc, implicating the APOBEC3B protein interaction network in cancer. Altogether, the results uncover novel functions and interactions of the APOBEC3 family and suggest they may have fundamental roles in cellular RNA biology, their protein-protein interactions are not redundant, and there are protein-protein interactions with tumor suppressors, suggesting a role in cancer biology.
Collapse
Affiliation(s)
- Gwendolyn M. Jang
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Arun Kumar Annan Sudarsan
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Centre for Commercialization of Regenerative Medicine (CCRM), 661 University Ave #1002, Toronto, ON M5G 1M1
| | - Arzhang Shayeganmehr
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Erika Prando Munhoz
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Department of Medicine, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW Calgary, AB T2N 4N1
| | - Reanna Lao
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Amit Gaba
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Milaid Granadillo Rodríguez
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| | - Robin P. Love
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
- Current Address: Faculty of Medicine & Dentistry, Department of Medicine, TB Program Evaluation & Research Unit, University of Alberta, 11402 University Avenue NW, Edmonton, AB, T6G 2J3
| | - Benjamin J. Polacco
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
| | - Yuan Zhou
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Nevan J. Krogan
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Robyn M. Kaake
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, 94158, USA
- Quantitative Biosciences Institute (QBI), University of California San Francisco, San Francisco, CA, 94158, USA
- J. David Gladstone Institutes, San Francisco, CA 94158, USA
| | - Linda Chelico
- University of Saskatchewan, College of Medicine, Biochemistry, Microbiology & Immunology, Saskatoon, Saskatchewan, Canada
| |
Collapse
|
6
|
Musier-Forsyth K, Rein A, Freed EO. Tribute to Dr. Judith G. Levin (1934-2023). Viruses 2024; 16:178. [PMID: 38399955 PMCID: PMC10893463 DOI: 10.3390/v16020178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 01/23/2024] [Indexed: 02/25/2024] Open
Abstract
Dr. Judith G. Levin passed away in Teaneck, NJ, USA, on 8 December 2023 [...].
Collapse
Affiliation(s)
- Karin Musier-Forsyth
- Department of Chemistry and Biochemistry, Center for Retrovirus Research, Center for RNA Biology, Ohio State University, Columbus, OH 43210, USA
| | - Alan Rein
- Retroviral Assembly Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA;
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA;
| |
Collapse
|
7
|
Byun H, Singh GB, Xu WK, Das P, Reyes A, Battenhouse A, Wylie DC, Lozano MM, Dudley JP. Apobec-Mediated Retroviral Hypermutation In Vivo is Dependent on Mouse Strain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.02.565355. [PMID: 37961113 PMCID: PMC10635078 DOI: 10.1101/2023.11.02.565355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Replication of the complex retrovirus mouse mammary tumor virus (MMTV) is antagonized by murine Apobec3 (mA3), a member of the Apobec family of cytidine deaminases. We have shown that MMTV-encoded Rem protein inhibits proviral mutagenesis by the Apobec enzyme, activation-induced cytidine deaminase (AID) during viral replication in BALB/c mice. To further study the role of Rem in vivo , we have infected C57BL/6 (B6) mice with a superantigen-independent lymphomagenic strain of MMTV (TBLV-WT) or a mutant strain (TBLV-SD) that is defective in Rem and its cleavage product Rem-CT. Unlike MMTV, TBLV induced T-cell tumors in µMT mice, indicating that mature B cells, which express the highest AID levels, are not required for TBLV replication. Compared to BALB/c, B6 mice were more susceptible to TBLV infection and tumorigenesis. The lack of Rem expression accelerated B6 tumorigenesis at limiting doses compared to TBLV-WT in either wild-type B6 or AID-deficient mice. However, unlike proviruses from BALB/c mice, high-throughput sequencing indicated that proviral G-to-A or C-to-T changes did not significantly differ in the presence and absence of Rem expression. Ex vivo stimulation showed higher levels of mA3 relative to AID in B6 compared to BALB/c splenocytes, but effects of agonists differed in the two strains. RNA-Seq revealed increased transcripts related to growth factor and cytokine signaling in TBLV-SD-induced tumors relative to those from TBLV-WT, consistent with a third Rem function. Thus, Rem-mediated effects on tumorigenesis in B6 mice are independent of Apobec-mediated proviral hypermutation.
Collapse
|
8
|
Delviks-Frankenberry KA, Ojha CR, Hermann KJ, Hu WS, Torbett BE, Pathak VK. Potent dual block to HIV-1 infection using lentiviral vectors expressing fusion inhibitor peptide mC46- and Vif-resistant APOBEC3G. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 33:794-809. [PMID: 37662965 PMCID: PMC10470399 DOI: 10.1016/j.omtn.2023.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/08/2023] [Indexed: 09/05/2023]
Abstract
Gene therapy strategies that effectively inhibit HIV-1 replication are needed to reduce the requirement for lifelong antiviral therapy and potentially achieve a functional cure. We previously designed self-activating lentiviral vectors that efficiently delivered and expressed a Vif-resistant mutant of APOBEC3G (A3G-D128K) to T cells, which potently inhibited HIV-1 replication and spread with no detectable virus. Here, we developed vectors that express A3G-D128K, membrane-associated fusion inhibitor peptide mC46, and O6-methylguanine-DNA-methyltransferase (MGMT) selectable marker for in vivo selection of transduced CD34+ hematopoietic stem and progenitor cells. MGMT-selected T cell lines MT4, CEM, and PM1 expressing A3G-D128K (with or without mC46) potently inhibited NL4-3 infection up to 45 days post infection with no detectable viral replication. Expression of mC46 was sufficient to block infection >80% in a single-cycle assay. Importantly, expression of mC46 provided a selective advantage to the A3G-D128K-modified T cells in the presence of replication competent virus. This combinational approach to first block HIV-1 entry with mC46, and then block any breakthrough infection with A3G-D128K, could provide an effective gene therapy treatment and a potential functional cure for HIV-1 infection.
Collapse
Affiliation(s)
- Krista A. Delviks-Frankenberry
- Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute at Frederick, Frederick, MD 21702, USA
| | - Chet R. Ojha
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, WA 98101, USA
| | - Kip J. Hermann
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Wei-Shau Hu
- Viral Recombination Section, HIV Dynamics and Replication Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Bruce E. Torbett
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, WA 98101, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
- Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98101, USA
| | - Vinay K. Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute at Frederick, Frederick, MD 21702, USA
| |
Collapse
|
9
|
Wang XF, Zhang X, Ma W, Li J, Wang X. Host cell restriction factors of equine infectious anemia virus. Virol Sin 2023; 38:485-496. [PMID: 37419416 PMCID: PMC10436108 DOI: 10.1016/j.virs.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 07/03/2023] [Indexed: 07/09/2023] Open
Abstract
Equine infectious anemia virus (EIAV) is a member of the lentivirus genus in the Retroviridae family and is considered an animal model for HIV/AIDS research. An attenuated EIAV vaccine, which was successfully developed in the 1970s by classical serial passage techniques, is the first and only lentivirus vaccine that has been widely used to date. Restriction factors are cellular proteins that provide an early line of defense against viral replication and spread by interfering with various critical steps in the viral replication cycle. However, viruses have evolved specific mechanisms to overcome these host barriers through adaptation. The battle between the viruses and restriction factors is actually a natural part of the viral replication process, which has been well studied in human immunodeficiency virus type 1 (HIV-1). EIAV has the simplest genome composition of all lentiviruses, making it an intriguing subject for understanding how the virus employs its limited viral proteins to overcome restriction factors. In this review, we summarize the current literature on the interactions between equine restriction factors and EIAV. The features of equine restriction factors and the mechanisms by which the EIAV counteract the restriction suggest that lentiviruses employ diverse strategies to counteract innate immune restrictions. In addition, we present our insights on whether restriction factors induce alterations in the phenotype of the attenuated EIAV vaccine.
Collapse
Affiliation(s)
- Xue-Feng Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Xiangmin Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Weiwei Ma
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Jiwei Li
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Xiaojun Wang
- State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150069, China.
| |
Collapse
|
10
|
Dudley JP. APOBECs: Our fickle friends? PLoS Pathog 2023; 19:e1011364. [PMID: 37200235 DOI: 10.1371/journal.ppat.1011364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023] Open
Affiliation(s)
- Jaquelin P Dudley
- Department of Molecular Biosciences and LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, Texas, United States of America
| |
Collapse
|
11
|
Britan-Rosich Y, Ma J, Kotler E, Hassan F, Botvinnik A, Smith Y, Moshel O, Nasereddin A, Sharma G, Pikarsky E, Ross S, Kotler M. APOBEC3G protects the genome of human cultured cells and mice from radiation-induced damage. FEBS J 2023; 290:1822-1839. [PMID: 36325681 PMCID: PMC10079569 DOI: 10.1111/febs.16673] [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: 03/24/2022] [Revised: 09/14/2022] [Accepted: 11/02/2022] [Indexed: 11/06/2022]
Abstract
Cytosine deaminases AID/APOBEC proteins act as potent nucleic acid editors, playing important roles in innate and adaptive immunity. However, the mutagenic effects of some of these proteins compromise genomic integrity and may promote tumorigenesis. Here, we demonstrate that human APOBEC3G (A3G), in addition to its role in innate immunity, promotes repair of double-strand breaks (DSBs) in vitro and in vivo. Transgenic mice expressing A3G successfully survived lethal irradiation, whereas wild-type controls quickly succumbed to radiation syndrome. Mass spectrometric analyses identified the differential upregulation of a plethora of proteins involved in DSB repair pathways in A3G-expressing cells early following irradiation to facilitate repair. Importantly, we find that A3G not only accelerates DSB repair but also promotes deamination-dependent error-free rejoining. These findings have two implications: (a) strategies aimed at inhibiting A3G may improve the efficacy of genotoxic therapies used to cure malignant tumours; and (b) enhancing A3G activity may reduce acute radiation syndrome in individuals exposed to ionizing radiation.
Collapse
Affiliation(s)
- Yelena Britan-Rosich
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Jing Ma
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, USA
| | - Eran Kotler
- Department of Genetics, Stanford University School of Medicine, Ca, USA
| | - Faizan Hassan
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Alexander Botvinnik
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Yoav Smith
- Genomic Data Analysis, Hadassah Medical School, Hebrew University, Jerusalem, Israel
| | - Ofra Moshel
- Core Research Facility, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Abed Nasereddin
- Core Research Facility of the Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Gunjan Sharma
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Eli Pikarsky
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Susan Ross
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, USA
| | - Moshe Kotler
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| |
Collapse
|
12
|
Bao Q, Zhou J. Various strategies for developing APOBEC3G protectors to circumvent human immunodeficiency virus type 1. Eur J Med Chem 2023; 250:115188. [PMID: 36773550 DOI: 10.1016/j.ejmech.2023.115188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/18/2023] [Accepted: 02/04/2023] [Indexed: 02/09/2023]
Abstract
Host restriction factor APOBEC3G (A3G) efficiently restricts Vif-deficient HIV-1 by being packaged with progeny virions and causing the G to A mutation during HIV-1 viral DNA synthesis as the progeny virus infects new cells. HIV-1 expresses Vif protein to resist the activity of A3G by mediating A3G degradation. This process requires the self-association of Vif in concert with A3G proteins, protein chaperones, and factors of the ubiquitination machinery, which are potential targets to discover novel anti-HIV drugs. This review will describe compounds that have been reported so far to inhibit viral replication of HIV-1 by protecting A3G from Vif-mediated degradation.
Collapse
Affiliation(s)
- Qiqi Bao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China
| | - Jinming Zhou
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China.
| |
Collapse
|
13
|
Stability of APOBEC3F in the Presence of the APOBEC3 Antagonist HIV-1 Vif Increases at the Expense of Co-Expressed APOBEC3H Haplotype I. Viruses 2023; 15:v15020463. [PMID: 36851677 PMCID: PMC9960753 DOI: 10.3390/v15020463] [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: 12/29/2022] [Revised: 02/03/2023] [Accepted: 02/04/2023] [Indexed: 02/10/2023] Open
Abstract
The seven human APOBEC3 enzymes (APOBEC3A through H, excluding E) are host restriction factors. Most of the APOBEC3 enzymes can restrict HIV-1 replication with different efficiencies. The HIV-1 Vif protein combats APOBEC3-mediated restriction by inducing ubiquitination and degradation in the proteasome. APOBEC3F and APOBEC3G can hetero-oligomerize, which increases their restriction capacity and resistance to Vif. Here we determined if APOBEC3C, APOBEC3F, or APOBEC3G could hetero-oligomerize with APOBEC3H haplotype I. APOBEC3H haplotype I has a short half-life in cells due to ubiquitination and degradation by host proteins, but is also resistant to Vif. We hypothesized that hetero-oligomerization with APOBEC3H haplotype I may result in less Vif-mediated degradation of the interacting APOBEC3 and stabilize APOBEC3H haplotype I, resulting in more efficient HIV-1 restriction. Although we found that all three APOBEC3s could interact with APOBEC3H haplotype I, only APOBEC3F affected APOBEC3H haplotype I by surprisingly accelerating its proteasomal degradation. However, this increased APOBEC3F levels in cells and virions in the absence or presence of Vif and enabled APOBEC3F-mediated restriction of HIV-1 in the presence of Vif. Altogether, the data suggest that APOBEC3 enzymes can co-regulate each other at the protein level and that they cooperate to ensure HIV-1 inactivation rather than evolution.
Collapse
|
14
|
Ajoge HO, Renner TM, Bélanger K, Greig M, Dankar S, Kohio HP, Coleman MD, Ndashimye E, Arts EJ, Langlois MA, Barr SD. Antiretroviral APOBEC3 cytidine deaminases alter HIV-1 provirus integration site profiles. Nat Commun 2023; 14:16. [PMID: 36627271 PMCID: PMC9832166 DOI: 10.1038/s41467-022-35379-y] [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: 11/11/2019] [Accepted: 11/30/2022] [Indexed: 01/12/2023] Open
Abstract
APOBEC3 (A3) proteins are host-encoded deoxycytidine deaminases that provide an innate immune barrier to retroviral infection, notably against HIV-1. Low levels of deamination are believed to contribute to the genetic evolution of HIV-1, while intense catalytic activity of these proteins can induce catastrophic hypermutation in proviral DNA leading to near-total HIV-1 restriction. So far, little is known about how A3 cytosine deaminases might impact HIV-1 proviral DNA integration sites in human chromosomal DNA. Using a deep sequencing approach, we analyze the influence of catalytic active and inactive APOBEC3F and APOBEC3G on HIV-1 integration site selections. Here we show that DNA editing is detected at the extremities of the long terminal repeat regions of the virus. Both catalytic active and non-catalytic A3 mutants decrease insertions into gene coding sequences and increase integration sites into SINE elements, oncogenes and transcription-silencing non-B DNA features. Our data implicates A3 as a host factor influencing HIV-1 integration site selection and also promotes what appears to be a more latent expression profile.
Collapse
Affiliation(s)
- Hannah O Ajoge
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada
| | - Tyler M Renner
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Kasandra Bélanger
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Matthew Greig
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Samar Dankar
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Hinissan P Kohio
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada
| | - Macon D Coleman
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada
| | - Emmanuel Ndashimye
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada
| | - Eric J Arts
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada
| | - Marc-André Langlois
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada. .,Ottawa Center for Infection, Immunity and Inflammation (CI3), Ottawa, ON, Canada.
| | - Stephen D Barr
- Western University, Schulich School of Medicine and Dentistry, Department of Microbiology and Immunology, London, ON, Canada.
| |
Collapse
|
15
|
Ito F, Alvarez-Cabrera AL, Liu S, Yang H, Shiriaeva A, Zhou ZH, Chen XS. Structural basis for HIV-1 antagonism of host APOBEC3G via Cullin E3 ligase. SCIENCE ADVANCES 2023; 9:eade3168. [PMID: 36598981 PMCID: PMC9812381 DOI: 10.1126/sciadv.ade3168] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Human APOBEC3G (A3G) is a virus restriction factor that inhibits HIV-1 replication and triggers lethal hypermutation on viral reverse transcripts. HIV-1 viral infectivity factor (Vif) breaches this host A3G immunity by hijacking a cellular E3 ubiquitin ligase complex to target A3G for ubiquitination and degradation. The molecular mechanism of A3G targeting by Vif-E3 ligase is unknown, limiting the antiviral efforts targeting this host-pathogen interaction crucial for HIV-1 infection. Here, we report the cryo-electron microscopy structures of A3G bound to HIV-1 Vif in complex with T cell transcription cofactor CBF-β and multiple components of the Cullin-5 RING E3 ubiquitin ligase. The structures reveal unexpected RNA-mediated interactions of Vif with A3G primarily through A3G's noncatalytic domain, while A3G's catalytic domain is poised for ubiquitin transfer. These structures elucidate the molecular mechanism by which HIV-1 Vif hijacks the host ubiquitin ligase to specifically target A3G to establish infection and offer structural information for the rational development of antiretroviral therapeutics.
Collapse
Affiliation(s)
- Fumiaki Ito
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Ana L. Alvarez-Cabrera
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - Shiheng Liu
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Anna Shiriaeva
- Department of Biological Chemistry, UCLA, Los Angeles, CA, USA
| | - Z. Hong Zhou
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - Xiaojiang S. Chen
- Molecular and Computational Biology, Departments of Biological Sciences, University of Southern California, Los Angeles, CA, USA
- Genetic, Molecular, and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA
- Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
16
|
Yang H, Kim K, Li S, Pacheco J, Chen XS. Structural basis of sequence-specific RNA recognition by the antiviral factor APOBEC3G. Nat Commun 2022; 13:7498. [PMID: 36470880 PMCID: PMC9722718 DOI: 10.1038/s41467-022-35201-9] [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: 05/11/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022] Open
Abstract
An essential step in restricting HIV infectivity by the antiviral factor APOBEC3G is its incorporation into progeny virions via binding to HIV RNA. However, the mechanism of APOBEC3G capturing viral RNA is unknown. Here, we report crystal structures of a primate APOBEC3G bound to different types of RNAs, revealing that APOBEC3G specifically recognizes unpaired 5'-AA-3' dinucleotides, and to a lesser extent, 5'-GA-3' dinucleotides. APOBEC3G binds to the common 3'A in the AA/GA motifs using an aromatic/hydrophobic pocket in the non-catalytic domain. It binds to the 5'A or 5'G in the AA/GA motifs using an aromatic/hydrophobic groove conformed between the non-catalytic and catalytic domains. APOBEC3G RNA binding property is distinct from that of the HIV nucleocapsid protein recognizing unpaired guanosines. Our findings suggest that the sequence-specific RNA recognition is critical for APOBEC3G virion packaging and restricting HIV infectivity.
Collapse
Affiliation(s)
- Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Kyumin Kim
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Shuxing Li
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089 USA
| | - Josue Pacheco
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Xiaojiang S. Chen
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, Los Angeles, CA 90033 USA ,grid.42505.360000 0001 2156 6853Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033 USA
| |
Collapse
|
17
|
Modenini G, Abondio P, Boattini A. The coevolution between APOBEC3 and retrotransposons in primates. Mob DNA 2022; 13:27. [PMID: 36443831 PMCID: PMC9706992 DOI: 10.1186/s13100-022-00283-1] [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: 09/06/2022] [Accepted: 10/31/2022] [Indexed: 12/02/2022] Open
Abstract
Retrotransposons are genetic elements with the ability to replicate in the genome using reverse transcriptase: they have been associated with the development of different biological structures, such as the Central Nervous System (CNS), and their high mutagenic potential has been linked to various diseases, including cancer and neurological disorders. Throughout evolution and over time, Primates and Homo had to cope with infections from viruses and bacteria, and also with endogenous retroelements. Therefore, host genomes have evolved numerous methods to counteract the activity of endogenous and exogenous pathogens, and the APOBEC3 family of mutators is a prime example of a defensive mechanism in this context.In most Primates, there are seven members of the APOBEC3 family of deaminase proteins: among their functions, there is the ability to inhibit the mobilization of retrotransposons and the functionality of viruses. The evolution of the APOBEC3 proteins found in Primates is correlated with the expansion of two major families of retrotransposons, i.e. ERV and LINE-1.In this review, we will discuss how the rapid expansion of the APOBEC3 family is linked to the evolution of retrotransposons, highlighting the strong evolutionary arms race that characterized the history of APOBEC3s and endogenous retroelements in Primates. Moreover, the possible role of this relationship will be assessed in the context of embryonic development and brain-associated diseases.
Collapse
Affiliation(s)
- Giorgia Modenini
- grid.6292.f0000 0004 1757 1758Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Paolo Abondio
- grid.6292.f0000 0004 1757 1758Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy ,grid.6292.f0000 0004 1757 1758Department of Cultural Heritage, University of Bologna, Ravenna, Italy
| | - Alessio Boattini
- grid.6292.f0000 0004 1757 1758Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| |
Collapse
|
18
|
Dominant Negative Mutants of Human Immunodeficiency Virus Type 1 Viral Infectivity Factor (Vif) Disrupt Core-Binding Factor Beta-Vif Interaction. J Virol 2022; 96:e0055522. [PMID: 35950859 PMCID: PMC9472641 DOI: 10.1128/jvi.00555-22] [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: 11/20/2022] Open
Abstract
Apolipoprotein B mRNA-editing catalytic polypeptide-like 3 family members (APOBEC3s) are host restriction factors that inhibit viral replication. Viral infectivity factor (Vif), a human immunodeficiency virus type 1 (HIV-1) accessory protein, mediates the degradation of APOBEC3s by forming the Vif-E3 complex, in which core-binding factor beta (CBFβ) is an essential molecular chaperone. Here, we screened nonfunctional Vif mutants with high affinity for CBFβ to inhibit HIV-1 in a dominant negative manner. We applied the yeast surface display technology to express Vif random mutant libraries, and mutants showing high CBFβ affinity were screened using flow cytometry. Most of the screened Vif mutants containing random mutations of different frequencies were able to rescue APOBEC3G (A3G). In the subsequent screening, three of the mutants restricted HIV-1, recovered G-to-A hypermutation, and rescued APOBEC3s. Among them, Vif-6M showed a cross-protection effect toward APOBEC3C, APOBEC3F, and African green monkey A3G. Stable expression of Vif-6M in T lymphocytes inhibited the viral replication in newly HIV-1-infected cells and the chronically infected cell line H9/HXB2. Furthermore, the expression of Vif-6M provided a survival advantage to T lymphocytes infected with HIV-1. These results suggest that dominant negative Vif mutants acting on the Vif-CBFβ target potently restrict HIV-1. IMPORTANCE Antiviral therapy cannot eliminate HIV and exhibits disadvantages such as drug resistance and toxicity. Therefore, novel strategies for inhibiting viral replication in patients with HIV are urgently needed. APOBEC3s in host cells are able to inhibit viral replication but are antagonized by HIV-1 Vif-mediated degradation. Therefore, we screened nonfunctional Vif mutants with high affinity for CBFβ to compete with the wild-type Vif (wtVif) as a potential strategy to assist with HIV-1 treatment. Most screened mutants rescued the expression of A3G in the presence of wtVif, especially Vif-6M, which could protect various APOBEC3s and improve the incorporation of A3G into HIV-1 particles. Transduction of Vif-6M into T lymphocytes inhibited the replication of the newly infected virus and the chronically infected virus. These data suggest that Vif mutants targeting the Vif-CBFβ interaction may be promising in the development of a new AIDS therapeutic strategy.
Collapse
|
19
|
Small-Angle X-ray Scattering (SAXS) Measurements of APOBEC3G Provide Structural Basis for Binding of Single-Stranded DNA and Processivity. Viruses 2022; 14:v14091974. [PMID: 36146779 PMCID: PMC9505750 DOI: 10.3390/v14091974] [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: 06/29/2022] [Revised: 08/05/2022] [Accepted: 08/31/2022] [Indexed: 11/17/2022] Open
Abstract
APOBEC3 enzymes are polynucleotide deaminases, converting cytosine to uracil on single-stranded DNA (ssDNA) and RNA as part of the innate immune response against viruses and retrotransposons. APOBEC3G is a two-domain protein that restricts HIV. Although X-ray single-crystal structures of individual catalytic domains of APOBEC3G with ssDNA as well as full-length APOBEC3G have been solved recently, there is little structural information available about ssDNA interaction with the full-length APOBEC3G or any other two-domain APOBEC3. Here, we investigated the solution-state structures of full-length APOBEC3G with and without a 40-mer modified ssDNA by small-angle X-ray scattering (SAXS), using size-exclusion chromatography (SEC) immediately prior to irradiation to effect partial separation of multi-component mixtures. To prevent cytosine deamination, the target 2′-deoxycytidine embedded in 40-mer ssDNA was replaced by 2′-deoxyzebularine, which is known to inhibit APOBEC3A, APOBEC3B and APOBEC3G when incorporated into short ssDNA oligomers. Full-length APOBEC3G without ssDNA comprised multiple multimeric species, of which tetramer was the most scattering species. The structure of the tetramer was elucidated. Dimeric interfaces significantly occlude the DNA-binding interface, whereas the tetrameric interface does not. This explains why dimers completely disappeared, and monomeric protein species became dominant, when ssDNA was added. Data analysis of the monomeric species revealed a full-length APOBEC3G–ssDNA complex that gives insight into the observed “jumping” behavior revealed in studies of enzyme processivity. This solution-state SAXS study provides the first structural model of ssDNA binding both domains of APOBEC3G and provides data to guide further structural and enzymatic work on APOBEC3–ssDNA complexes.
Collapse
|
20
|
Carcone A, Journo C, Dutartre H. Is the HTLV-1 Retrovirus Targeted by Host Restriction Factors? Viruses 2022; 14:v14081611. [PMID: 35893677 PMCID: PMC9332716 DOI: 10.3390/v14081611] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 02/04/2023] Open
Abstract
Human T cell leukemia virus type 1 (HTLV-1), the etiological agent of adult T cell leukemia/lymphoma (ATLL) and of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), was identified a few years before Human Immunodeficiency Virus (HIV). However, forty years later, our comprehension of HTLV-1 immune detection and the host immune responses to HTLV-1 is far more limited than for HIV. In addition to innate and adaptive immune responses that rely on specialized cells of the immune system, host cells may also express a range of antiviral factors that inhibit viral replication at different stages of the cycle, in a cell-autonomous manner. Multiple antiviral factors allowing such an intrinsic immunity have been primarily and extensively described in the context HIV infection. Here, we provide an overview of whether known HIV restriction factors might act on HTLV-1 replication. Interestingly, many of them do not exert any antiviral activity against HTLV-1, and we discuss viral replication cycle specificities that could account for these differences. Finally, we highlight future research directions that could help to identify antiviral factors specific to HTLV-1.
Collapse
|
21
|
Differential Activity of APOBEC3F, APOBEC3G, and APOBEC3H in the Restriction of HIV-2. J Mol Biol 2022; 434:167355. [PMID: 34774569 PMCID: PMC8752514 DOI: 10.1016/j.jmb.2021.167355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 11/04/2021] [Accepted: 11/04/2021] [Indexed: 02/01/2023]
Abstract
Human immunodeficiency virus (HIV) mutagenesis is driven by a variety of internal and external sources, including the host APOBEC3 (apolipoprotein B mRNA editing enzyme catalytic polypetide-like 3; A3) family of mutagenesis factors, which catalyze G-to-A transition mutations during virus replication. HIV-2 replication is characterized by a relative lack of G-to-A mutations, suggesting infrequent mutagenesis by A3 proteins. To date, the activity of the A3 repertoire against HIV-2 has remained largely uncharacterized, and the mutagenic activity of these proteins against HIV-2 remains to be elucidated. In this study, we provide the first comprehensive characterization of the restrictive capacity of A3 proteins against HIV-2 in cell culture using a dual fluorescent reporter HIV-2 vector virus. We found that A3F, A3G, and A3H restricted HIV-2 infectivity in the absence of Vif and were associated with significant increases in the frequency of viral mutants. These proteins increased the frequency of G-to-A mutations within the proviruses of infected cells as well. A3G and A3H also reduced HIV-2 infectivity via inhibition of reverse transcription and the accumulation of DNA products during replication. In contrast, A3D did not exhibit any restrictive activity against HIV-2, even at higher expression levels. Taken together, these results provide evidence that A3F, A3G, and A3H, but not A3D, are capable of HIV-2 restriction. Differences in A3-mediated restriction of HIV-1 and HIV-2 may serve to provide new insights in the observed mutation profiles of these viruses.
Collapse
|
22
|
A Conserved uORF Regulates APOBEC3G Translation and Is Targeted by HIV-1 Vif Protein to Repress the Antiviral Factor. Biomedicines 2021; 10:biomedicines10010013. [PMID: 35052693 PMCID: PMC8773096 DOI: 10.3390/biomedicines10010013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 11/17/2022] Open
Abstract
The HIV-1 Vif protein is essential for viral fitness and pathogenicity. Vif decreases expression of cellular restriction factors APOBEC3G (A3G), A3F, A3D and A3H, which inhibit HIV-1 replication by inducing hypermutation during reverse transcription. Vif counteracts A3G at several levels (transcription, translation, and protein degradation) that altogether reduce the levels of A3G in cells and prevent its incorporation into viral particles. How Vif affects A3G translation remains unclear. Here, we uncovered the importance of a short conserved uORF (upstream ORF) located within two critical stem-loop structures of the 5′ untranslated region (5′-UTR) of A3G mRNA for this process. A3G translation occurs through a combination of leaky scanning and translation re-initiation and the presence of an intact uORF decreases the extent of global A3G translation under normal conditions. Interestingly, the uORF is also absolutely required for Vif-mediated translation inhibition and redirection of A3G mRNA into stress granules. Overall, we discovered that A3G translation is regulated by a small uORF conserved in the human population and that Vif uses this specific feature to repress its translation.
Collapse
|
23
|
Xie Y, Zhang S, Deng T, Zhang K, Ren J, Li J. A Novel DNAzyme Signal Amplification-based Colorimetric Method for RNase H Assays. ANAL SCI 2021; 37:1675-1680. [PMID: 33162413 DOI: 10.2116/analsci.20p337] [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: 11/23/2022]
Abstract
A simple visual strategy was developed for the RNase H colorimetric measurement using DNAzyme-mediated signal amplification. When RNase H was presented, the RNA strand of the duplex formed by the G-rich DNA sequence (G-Rich) and its complementary RNA sequence (cp-RNA) was digested, releasing G-Rich to form HRP-mimicking DNAzymes of the G-quadruplex/hemin complexes in the presence of hemin. These DNAzymes catalyze the oxidation reaction of the substrate of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) to produce green-color products of ABTS•-, allowing for the detection of RNase H. A horseradish peroxidase (HRP)-mimicking DNAzyme of the G-quadruplex/hemin complex was used to mediate the signal amplification in the sensing strategy, resulting in high selectivity and sensitivity. This proposed colorimetric method shows a low detection limit of 0.04 U/mL, with a detection range of 0.1 to 3 U/mL. Moreover, this colorimetric method has been successfully used for RNase H assays in complicated biosamples, such as cell lysates. These results indicate that our colorimetric method not only detects RNase H in an ideal system, but also in real samples.
Collapse
Affiliation(s)
- Ye Xie
- Institute of Applied Chemistry, School of Science, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, Central South University of Forestry and Technology
| | - Sina Zhang
- Institute of Applied Chemistry, School of Science, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, Central South University of Forestry and Technology
| | - Ting Deng
- Institute of Applied Chemistry, School of Science, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, Central South University of Forestry and Technology
| | - Ke Zhang
- Institute of Applied Chemistry, School of Science, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, Central South University of Forestry and Technology
| | - Jiali Ren
- Institute of Applied Chemistry, School of Science, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, Central South University of Forestry and Technology
| | - Jishan Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University
| |
Collapse
|
24
|
Gaba A, Hix MA, Suhail S, Flath B, Boysan B, Williams DR, Pelletier T, Emerman M, Morcos F, Cisneros GA, Chelico L. Divergence in Dimerization and Activity of Primate APOBEC3C. J Mol Biol 2021; 433:167306. [PMID: 34666043 PMCID: PMC9202443 DOI: 10.1016/j.jmb.2021.167306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 11/21/2022]
Abstract
The APOBEC3 (A3) family of single-stranded DNA cytidine deaminases are host restriction factors that inhibit lentiviruses, such as HIV-1, in the absence of the Vif protein that causes their degradation. Deamination of cytidine in HIV-1 (−)DNA forms uracil that causes inactivating mutations when uracil is used as a template for (+)DNA synthesis. For APOBEC3C (A3C), the chimpanzee and gorilla orthologues are more active than human A3C, and we determined that Old World Monkey A3C from rhesus macaque (rh) is not active against HIV-1. Biochemical, virological, and coevolutionary analyses combined with molecular dynamics simulations showed that the key amino acids needed to promote rhA3C antiviral activity, 44, 45, and 144, also promoted dimerization and changes to the dynamics of loop 1, near the enzyme active site. Although forced evolution of rhA3C resulted in a similar dimer interface with hominid A3C, the key amino acid contacts were different. Overall, our results determine the basis for why rhA3C is less active than human A3C and establish the amino acid network for dimerization and increased activity. Based on identification of the key amino acids determining Old World Monkey antiviral activity we predict that other Old World Monkey A3Cs did not impart anti-lentiviral activity, despite fixation of a key residue needed for hominid A3C activity. Overall, the coevolutionary analysis of the A3C dimerization interface presented also provides a basis from which to analyze dimerization interfaces of other A3 family members.
Collapse
Affiliation(s)
- Amit Gaba
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada. https://twitter.com/optimist1023
| | - Mark A Hix
- Department of Chemistry, University of North Texas, Denton, TX, USA. https://twitter.com/markahix
| | - Sana Suhail
- Department of Biological Sciences, Center for Systems Biology, University of Texas at Dallas, Richardson, TX, USA. https://twitter.com/sakuraa_329
| | - Ben Flath
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Brock Boysan
- Department of Chemistry, University of North Texas, Denton, TX, USA
| | - Danielle R Williams
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. https://twitter.com/dani_renee_
| | - Tomas Pelletier
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Michael Emerman
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. https://twitter.com/memerman
| | - Faruck Morcos
- Department of Biological Sciences, Center for Systems Biology, University of Texas at Dallas, Richardson, TX, USA; Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA. https://twitter.com/MorcosLab
| | - G Andrés Cisneros
- Department of Chemistry, University of North Texas, Denton, TX, USA. https://twitter.com/CisnerosRes
| | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
| |
Collapse
|
25
|
Wörmann SM, Zhang A, Thege FI, Cowan RW, Rupani DN, Wang R, Manning SL, Gates C, Wu W, Levin-Klein R, Rajapakshe KI, Yu M, Multani AS, Kang Y, Taniguchi CM, Schlacher K, Bellin MD, Katz MHG, Kim MP, Fleming JB, Gallinger S, Maddipati R, Harris RS, Notta F, Ross SR, Maitra A, Rhim AD. APOBEC3A drives deaminase domain-independent chromosomal instability to promote pancreatic cancer metastasis. NATURE CANCER 2021; 2:1338-1356. [PMID: 35121902 DOI: 10.1038/s43018-021-00268-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 09/14/2021] [Indexed: 02/06/2023]
Abstract
Despite efforts in understanding its underlying mechanisms, the etiology of chromosomal instability (CIN) remains unclear for many tumor types. Here, we identify CIN initiation as a previously undescribed function for APOBEC3A (A3A), a cytidine deaminase upregulated across cancer types. Using genetic mouse models of pancreatic ductal adenocarcinoma (PDA) and genomics analyses in human tumor cells we show that A3A-induced CIN leads to aggressive tumors characterized by enhanced early dissemination and metastasis in a STING-dependent manner and independently of the canonical deaminase functions of A3A. We show that A3A upregulation recapitulates numerous copy number alterations commonly observed in patients with PDA, including co-deletions in DNA repair pathway genes, which in turn render these tumors susceptible to poly (ADP-ribose) polymerase inhibition. Overall, our results demonstrate that A3A plays an unexpected role in PDA as a specific driver of CIN, with significant effects on disease progression and treatment.
Collapse
Affiliation(s)
- Sonja M Wörmann
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA.
- Department of Translational Molecular Pathology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA.
| | - Amy Zhang
- Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Fredrik I Thege
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Translational Molecular Pathology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Robert W Cowan
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Gastroenterology, Hepatology & Nutrition, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Dhwani N Rupani
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Gastroenterology, Hepatology & Nutrition, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Runsheng Wang
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Gastroenterology, Hepatology & Nutrition, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Sara L Manning
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Gastroenterology, Hepatology & Nutrition, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Chris Gates
- BRCF Bioinformatics Core, University of Michigan, School of Medicine, Ann Arbor, MI, USA
| | - Weisheng Wu
- BRCF Bioinformatics Core, University of Michigan, School of Medicine, Ann Arbor, MI, USA
| | - Rena Levin-Klein
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
| | - Kimal I Rajapakshe
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Meifang Yu
- Department of Experimental Radiation Oncology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Asha S Multani
- Department of Genetics, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Ya'an Kang
- Department of Surgical Oncology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Cullen M Taniguchi
- Department of Experimental Radiation Oncology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Katharina Schlacher
- Department of Cancer Biology, Division of Basic Science Research, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Melena D Bellin
- University of Minnesota Medical Center, Schulze Diabetes Institute, Minneapolis, MN, USA
| | - Matthew H G Katz
- Department of Surgical Oncology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Michael P Kim
- Department of Surgical Oncology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Jason B Fleming
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center, Tampa, FL, USA
| | | | - Ravikanth Maddipati
- Department of Internal Medicine and Hamon Center for Therapeutic Oncology Research and Children's Research Institute, UT Southwestern Medical Center, Dallas, TX, USA
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
- Howard Hughes Medical Institute, University of Minnesota, Minneapolis, Minnesota, USA
| | - Faiyaz Notta
- Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Susan R Ross
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Anirban Maitra
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
- Department of Translational Molecular Pathology, MD Anderson Cancer Center, University of Texas, Houston, TX, USA
| | - Andrew D Rhim
- Ahmed Cancer Center for Pancreatic Cancer Research, MD Anderson Cancer Center, University of Texas, Houston, TX, USA.
- Department of Gastroenterology, Hepatology & Nutrition, MD Anderson Cancer Center, University of Texas, Houston, TX, USA.
| |
Collapse
|
26
|
Chintala K, Mohareer K, Banerjee S. Dodging the Host Interferon-Stimulated Gene Mediated Innate Immunity by HIV-1: A Brief Update on Intrinsic Mechanisms and Counter-Mechanisms. Front Immunol 2021; 12:716927. [PMID: 34394123 PMCID: PMC8358655 DOI: 10.3389/fimmu.2021.716927] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/14/2021] [Indexed: 12/12/2022] Open
Abstract
Host restriction factors affect different phases of a viral life cycle, contributing to innate immunity as the first line of defense against viruses, including HIV-1. These restriction factors are constitutively expressed, but triggered upon infection by interferons. Both pre-integration and post-integration events of the HIV-1 life cycle appear to play distinct roles in the induction of interferon-stimulated genes (ISGs), many of which encode antiviral restriction factors. However, HIV-1 counteracts the mechanisms mediated by these restriction factors through its encoded components. Here, we review the recent findings of pathways that lead to the induction of ISGs, and the mechanisms employed by the restriction factors such as IFITMs, APOBEC3s, MX2, and ISG15 in preventing HIV-1 replication. We also reflect on the current understanding of the counter-mechanisms employed by HIV-1 to evade innate immune responses and overcome host restriction factors. Overall, this mini-review provides recent insights into the HIV-1-host cross talk bridging the understanding between intracellular immunity and research avenues in the field of therapeutic interventions against HIV-1.
Collapse
|
27
|
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.
Collapse
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
| |
Collapse
|
28
|
Gaba A, Flath B, Chelico L. Examination of the APOBEC3 Barrier to Cross Species Transmission of Primate Lentiviruses. Viruses 2021; 13:1084. [PMID: 34200141 PMCID: PMC8228377 DOI: 10.3390/v13061084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/12/2022] Open
Abstract
The transmission of viruses from animal hosts into humans have led to the emergence of several diseases. Usually these cross-species transmissions are blocked by host restriction factors, which are proteins that can block virus replication at a specific step. In the natural virus host, the restriction factor activity is usually suppressed by a viral antagonist protein, but this is not the case for restriction factors from an unnatural host. However, due to ongoing viral evolution, sometimes the viral antagonist can evolve to suppress restriction factors in a new host, enabling cross-species transmission. Here we examine the classical case of this paradigm by reviewing research on APOBEC3 restriction factors and how they can suppress human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). APOBEC3 enzymes are single-stranded DNA cytidine deaminases that can induce mutagenesis of proviral DNA by catalyzing the conversion of cytidine to promutagenic uridine on single-stranded viral (-)DNA if they escape the HIV/SIV antagonist protein, Vif. APOBEC3 degradation is induced by Vif through the proteasome pathway. SIV has been transmitted between Old World Monkeys and to hominids. Here we examine the adaptations that enabled such events and the ongoing impact of the APOBEC3-Vif interface on HIV in humans.
Collapse
Affiliation(s)
| | | | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SA S7H 0E5, Canada; (A.G.); (B.F.)
| |
Collapse
|
29
|
Hu Y, Knecht KM, Shen Q, Xiong Y. Multifaceted HIV-1 Vif interactions with human E3 ubiquitin ligase and APOBEC3s. FEBS J 2021; 288:3407-3417. [PMID: 32893454 PMCID: PMC8172064 DOI: 10.1111/febs.15550] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/01/2020] [Indexed: 12/31/2022]
Abstract
APOBEC3 (A3) proteins are a family of host antiviral restriction factors that potently inhibit various retroviral infections, including human immunodeficiency virus (HIV)-1. To overcome this restriction, HIV-1 virion infectivity factor (Vif) recruits the cellular cofactor CBFβ to assist in targeting A3 proteins to a host E3 ligase complex for polyubiquitination and subsequent proteasomal degradation. Intervention of the Vif-A3 interactions could be a promising therapeutic strategy to facilitate A3-mediated suppression of HIV-1 in patients. In this structural snapshot, we review the structural features of the recently determined structure of human A3F in complex with HIV-1 Vif and its cofactor CBFβ, discuss insights into the molecular principles of Vif-A3 interplay during the arms race between the virus and host, and highlight the therapeutic implications.
Collapse
Affiliation(s)
- Yingxia Hu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Kirsten M. Knecht
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Qi Shen
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| |
Collapse
|
30
|
McDonnell MM, Karvonen SC, Gaba A, Flath B, Chelico L, Emerman M. Highly-potent, synthetic APOBEC3s restrict HIV-1 through deamination-independent mechanisms. PLoS Pathog 2021; 17:e1009523. [PMID: 34170969 PMCID: PMC8266076 DOI: 10.1371/journal.ppat.1009523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/08/2021] [Accepted: 06/07/2021] [Indexed: 02/07/2023] Open
Abstract
The APOBEC3 (A3) genes encode cytidine deaminase proteins with potent antiviral and anti-retroelement activity. This locus is characterized by duplication, recombination, and deletion events that gave rise to the seven A3s found in primates. These include three single deaminase domain A3s (A3A, A3C, and A3H) and four double deaminase domain A3s (A3B, A3D, A3F, and A3G). The most potent of the A3 proteins against HIV-1 is A3G. However, it is not clear if double deaminase domain A3s have a generalized functional advantage to restrict HIV-1. In order to test whether superior restriction factors could be created by genetically linking single A3 domains into synthetic double domains, we linked A3C and A3H single domains in novel combinations. We found that A3C/A3H double domains acquired enhanced antiviral activity that is at least as potent, if not better than, A3G. Although these synthetic double domain A3s package into budding virions more efficiently than their respective single domains, this does not fully explain their gain of antiviral potency. The antiviral activity is conferred both by cytidine-deaminase dependent and independent mechanisms, with the latter correlating to an increase in RNA binding affinity. T cell lines expressing this A3C-A3H super restriction factor are able to control replicating HIV-1ΔVif infection to similar levels as A3G. Together, these data show that novel combinations of A3 domains are capable of gaining potent antiviral activity to levels similar to the most potent genome-encoded A3s, via a primarily non-catalytic mechanism.
Collapse
Affiliation(s)
- Mollie M. McDonnell
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, Washington, United States of America
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Suzanne C. Karvonen
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Amit Gaba
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Ben Flath
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Michael Emerman
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| |
Collapse
|
31
|
Botvinnik A, Shivam P, Smith Y, Sharma G, Olshevsky U, Moshel O, Manevitch Z, Climent N, Oliva H, Britan-Rosich E, Kotler M. APOBEC3G rescues cells from the deleterious effects of DNA damage. FEBS J 2021; 288:6063-6077. [PMID: 33999509 DOI: 10.1111/febs.16025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 04/25/2021] [Accepted: 05/14/2021] [Indexed: 11/30/2022]
Abstract
Human apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G (hA3G), a member of the APOBEC family, was described as an anti-HIV-1 restriction factor, deaminating reverse transcripts of the HIV-1 genome. Several types of cancer cells that express high levels of A3G, such as diffuse large B-cell lymphoma cells and glioblastomas, show enhanced cell survival after ionizing radiation and chemotherapy treatments. Previously, we showed that hA3G promotes (DNA) double-strand breaks repair in cultured cells and rescues transgenic mice from a lethal dose of ionizing radiation. Here, we show that A3G rescues cells from the detrimental effects of DNA damage induced by ultraviolet irradiation and by combined bromodeoxyuridine and ultraviolet treatments. The combined treatments stimulate the synthesis of cellular proteins, which are exclusively associated with A3G expression. These proteins participate mainly in nucleotide excision repair and homologous recombination DNA repair pathways. Our results implicate A3G inhibition as a potential strategy for increasing tumor cell sensitivity to genotoxic treatments.
Collapse
Affiliation(s)
- Alexander Botvinnik
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Pushkar Shivam
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Yoav Smith
- Genomic Data Analysis, Hadassah Medical School, Hebrew University, Jerusalem, Israel
| | - Gunjan Sharma
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Udy Olshevsky
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Ofra Moshel
- Core Research Facility, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Zakhariya Manevitch
- Core Research Facility, Light Microscopy and Image Analysis Laboratory, Hadassah Medical School, Hebrew University, Jerusalem, Israel
| | - Nuria Climent
- Faculty of Medicine, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)-AIDS Research Group and HIV Vaccine Development in Catalonia (HIVACAT), Hospital Clínic de Barcelona, University of Barcelona, Barcelona, Spain
| | | | - Elena Britan-Rosich
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Moshe Kotler
- Department of Pathology and Immunology, The Lautenberg Center for Immunology and Cancer Research, The Hebrew University Hadassah Medical School, Jerusalem, Israel
| |
Collapse
|
32
|
Degradation-Independent Inhibition of APOBEC3G by the HIV-1 Vif Protein. Viruses 2021; 13:v13040617. [PMID: 33916704 PMCID: PMC8066197 DOI: 10.3390/v13040617] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 12/20/2022] Open
Abstract
The ubiquitin–proteasome system plays an important role in the cell under normal physiological conditions but also during viral infections. Indeed, many auxiliary proteins from the (HIV-1) divert this system to its own advantage, notably to induce the degradation of cellular restriction factors. For instance, the HIV-1 viral infectivity factor (Vif) has been shown to specifically counteract several cellular deaminases belonging to the apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC3 or A3) family (A3A to A3H) by recruiting an E3-ubiquitin ligase complex and inducing their polyubiquitination and degradation through the proteasome. Although this pathway has been extensively characterized so far, Vif has also been shown to impede A3s through degradation-independent processes, but research on this matter remains limited. In this review, we describe our current knowledge regarding the degradation-independent inhibition of A3s, and A3G in particular, by the HIV-1 Vif protein, the molecular mechanisms involved, and highlight important properties of this small viral protein.
Collapse
|
33
|
Insights into the Structures and Multimeric Status of APOBEC Proteins Involved in Viral Restriction and Other Cellular Functions. Viruses 2021; 13:v13030497. [PMID: 33802945 PMCID: PMC8002816 DOI: 10.3390/v13030497] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/15/2021] [Accepted: 03/15/2021] [Indexed: 12/16/2022] Open
Abstract
Apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC) proteins belong to a family of deaminase proteins that can catalyze the deamination of cytosine to uracil on single-stranded DNA or/and RNA. APOBEC proteins are involved in diverse biological functions, including adaptive and innate immunity, which are critical for restricting viral infection and endogenous retroelements. Dysregulation of their functions can cause undesired genomic mutations and RNA modification, leading to various associated diseases, such as hyper-IgM syndrome and cancer. This review focuses on the structural and biochemical data on the multimerization status of individual APOBECs and the associated functional implications. Many APOBECs form various multimeric complexes, and multimerization is an important way to regulate functions for some of these proteins at several levels, such as deaminase activity, protein stability, subcellular localization, protein storage and activation, virion packaging, and antiviral activity. The multimerization of some APOBECs is more complicated than others, due to the associated complex RNA binding modes.
Collapse
|
34
|
Jaguva Vasudevan AA, Balakrishnan K, Franken A, Krikoni A, Häussinger D, Luedde T, Münk C. Murine leukemia virus resists producer cell APOBEC3A by its Glycosylated Gag but not target cell APOBEC3A. Virology 2021; 557:1-14. [PMID: 33581610 DOI: 10.1016/j.virol.2021.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 01/22/2021] [Accepted: 01/29/2021] [Indexed: 12/14/2022]
Abstract
The human APOBEC3A (A3A) polynucleotide cytidine deaminase has been shown to have antiviral activity against HTLV-1 but not HIV-1, when expressed in the virus producer cell. In viral target cells, high levels of endogenous A3A activity have been associated with the restriction of HIV-1 during infection. Here we demonstrate that A3A derived from both target cells and producer cells can block the infection of Moloney-MLV (MLV) and related AKV-derived strains of MLV in a deaminase-dependent mode. Furthermore, glycosylated Gag (glycoGag) of MLV inhibits the encapsidation of human A3A, but target cell A3A was not affected by glycoGag and exerted deamination of viral DNA. Importantly, our results clearly indicate that poor glycoGag expression in MLV gag-pol packaging constructs as compared to abundant levels in full-length amphotropic MLV makes these viral vectors sensitive to A3A-mediated restriction. This raises the possibility of acquiring A3A-induced mutations in retroviral gene therapy applications.
Collapse
Affiliation(s)
- Ananda Ayyappan Jaguva Vasudevan
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany.
| | - Kannan Balakrishnan
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany; Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, India
| | - André Franken
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Aikaterini Krikoni
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Tom Luedde
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225, Düsseldorf, Germany.
| |
Collapse
|
35
|
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.
Collapse
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
| |
Collapse
|
36
|
Hakata Y, Miyazawa M. Deaminase-Independent Mode of Antiretroviral Action in Human and Mouse APOBEC3 Proteins. Microorganisms 2020; 8:microorganisms8121976. [PMID: 33322756 PMCID: PMC7764128 DOI: 10.3390/microorganisms8121976] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 02/06/2023] Open
Abstract
Apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) proteins (APOBEC3s) are deaminases that convert cytosines to uracils predominantly on a single-stranded DNA, and function as intrinsic restriction factors in the innate immune system to suppress replication of viruses (including retroviruses) and movement of retrotransposons. Enzymatic activity is supposed to be essential for the APOBEC3 antiviral function. However, it is not the only way that APOBEC3s exert their biological function. Since the discovery of human APOBEC3G as a restriction factor for HIV-1, the deaminase-independent mode of action has been observed. At present, it is apparent that both the deaminase-dependent and -independent pathways are tightly involved not only in combating viruses but also in human tumorigenesis. Although the deaminase-dependent pathway has been extensively characterized so far, understanding of the deaminase-independent pathway remains immature. Here, we review existing knowledge regarding the deaminase-independent antiretroviral functions of APOBEC3s and their molecular mechanisms. We also discuss the possible unidentified molecular mechanism for the deaminase-independent antiretroviral function mediated by mouse APOBEC3.
Collapse
Affiliation(s)
- Yoshiyuki Hakata
- Department of Immunology, Kindai University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511, Japan;
- Correspondence: ; Tel.: +81-72-367-7660
| | - Masaaki Miyazawa
- Department of Immunology, Kindai University Faculty of Medicine, 377-2 Ohno-Higashi, Osaka-Sayama, Osaka 589-8511, Japan;
- Kindai University Anti-Aging Center, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan
| |
Collapse
|
37
|
Retroviral Restriction Factors and Their Viral Targets: Restriction Strategies and Evolutionary Adaptations. Microorganisms 2020; 8:microorganisms8121965. [PMID: 33322320 PMCID: PMC7764263 DOI: 10.3390/microorganisms8121965] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/30/2020] [Accepted: 12/08/2020] [Indexed: 12/17/2022] Open
Abstract
The evolutionary conflict between retroviruses and their vertebrate hosts over millions of years has led to the emergence of cellular innate immune proteins termed restriction factors as well as their viral antagonists. Evidence accumulated in the last two decades has substantially increased our understanding of the elaborate mechanisms utilized by these restriction factors to inhibit retroviral replication, mechanisms that either directly block viral proteins or interfere with the cellular pathways hijacked by the viruses. Analyses of these complex interactions describe patterns of accelerated evolution for these restriction factors as well as the acquisition and evolution of their virus-encoded antagonists. Evidence is also mounting that many restriction factors identified for their inhibition of specific retroviruses have broader antiviral activity against additional retroviruses as well as against other viruses, and that exposure to these multiple virus challenges has shaped their adaptive evolution. In this review, we provide an overview of the restriction factors that interfere with different steps of the retroviral life cycle, describing their mechanisms of action, adaptive evolution, viral targets and the viral antagonists that evolved to counter these factors.
Collapse
|
38
|
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.
Collapse
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.
| |
Collapse
|
39
|
Granadillo Rodríguez M, Flath B, Chelico L. The interesting relationship between APOBEC3 deoxycytidine deaminases and cancer: a long road ahead. Open Biol 2020; 10:200188. [PMID: 33292100 PMCID: PMC7776566 DOI: 10.1098/rsob.200188] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/26/2020] [Indexed: 12/24/2022] Open
Abstract
Cancer is considered a group of diseases characterized by uncontrolled growth and spread of abnormal cells and is propelled by somatic mutations. Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3) family of enzymes are endogenous sources of somatic mutations found in multiple human cancers. While these enzymes normally act as an intrinsic immune defence against viruses, they can also catalyse 'off-target' cytidine deamination in genomic single-stranded DNA intermediates. The deamination of cytosine forms uracil, which is promutagenic in DNA. Key factors to trigger the APOBEC 'off-target' activity are overexpression in a non-normal cell type, nuclear localization and replication stress. The resulting uracil-induced mutations contribute to genomic variation, which may result in neutral, beneficial or harmful consequences for the cancer. This review summarizes the functional and biochemical basis of the APOBEC3 enzyme activity and highlights their relationship with the most well-studied cancers in this particular context such as breast, lung, bladder, and human papillomavirus-associated cancers. We focus on APOBEC3A, APOBEC3B and APOBEC3H haplotype I because they are the leading candidates as sources of somatic mutations in these and other cancers. Also, we discuss the prognostic value of the APOBEC3 expression in drug resistance and response to therapies.
Collapse
Affiliation(s)
| | | | - Linda Chelico
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| |
Collapse
|
40
|
The Role of APOBECs in Viral Replication. Microorganisms 2020; 8:microorganisms8121899. [PMID: 33266042 PMCID: PMC7760323 DOI: 10.3390/microorganisms8121899] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/14/2022] Open
Abstract
Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) proteins are a diverse and evolutionarily conserved family of cytidine deaminases that provide a variety of functions from tissue-specific gene expression and immunoglobulin diversity to control of viruses and retrotransposons. APOBEC family expansion has been documented among mammalian species, suggesting a powerful selection for their activity. Enzymes with a duplicated zinc-binding domain often have catalytically active and inactive domains, yet both have antiviral function. Although APOBEC antiviral function was discovered through hypermutation of HIV-1 genomes lacking an active Vif protein, much evidence indicates that APOBECs also inhibit virus replication through mechanisms other than mutagenesis. Multiple steps of the viral replication cycle may be affected, although nucleic acid replication is a primary target. Packaging of APOBECs into virions was first noted with HIV-1, yet is not a prerequisite for viral inhibition. APOBEC antagonism may occur in viral producer and recipient cells. Signatures of APOBEC activity include G-to-A and C-to-T mutations in a particular sequence context. The importance of APOBEC activity for viral inhibition is reflected in the identification of numerous viral factors, including HIV-1 Vif, which are dedicated to antagonism of these deaminases. Such viral antagonists often are only partially successful, leading to APOBEC selection for viral variants that enhance replication or avoid immune elimination.
Collapse
|
41
|
Maiti A, Myint W, Delviks-Frankenberry KA, Hou S, Kanai T, Balachandran V, Sierra Rodriguez C, Tripathi R, Kurt Yilmaz N, Pathak VK, Schiffer CA, Matsuo H. Crystal Structure of a Soluble APOBEC3G Variant Suggests ssDNA to Bind in a Channel that Extends between the Two Domains. J Mol Biol 2020; 432:6042-6060. [PMID: 33098858 DOI: 10.1016/j.jmb.2020.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/09/2020] [Accepted: 10/16/2020] [Indexed: 11/16/2022]
Abstract
APOBEC3G (A3G) is a single-stranded DNA (ssDNA) cytosine deaminase that can restrict HIV-1 infection by mutating the viral genome. A3G consists of a non-catalytic N-terminal domain (NTD) and a catalytic C-terminal domain (CTD) connected by a short linker. While the CTD catalyzes cytosine deamination, the NTD is believed to provide additional affinity for ssDNA. Structures of both A3G domains have been solved individually; however, a full-length A3G structure has been challenging. Recently, crystal structures of full-length rhesus macaque A3G variants were solved which suggested dimerization mechanisms and RNA binding surfaces, whereas the dimerization appeared to compromise catalytic activity. We determined the crystal structure of a soluble variant of human A3G (sA3G) at 2.5 Å and from these data generated a model structure of wild-type A3G. This model demonstrated that the NTD was rotated 90° relative to the CTD along the major axis of the molecule, an orientation that forms a positively charged channel connected to the CTD catalytic site, consisting of NTD loop-1 and CTD loop-3. Structure-based mutations, in vitro deamination and DNA binding assays, and HIV-1 restriction assays identify R24, located in the NTD loop-1, as essential to a critical interaction with ssDNA. Furthermore, sA3G was shown to bind a deoxy-cytidine dinucleotide near the catalytic Zn2+, yet not in the catalytic position, where the interactions between deoxy-cytidines and CTD loop-1 and loop-7 residues were different from those formed with substrate. These new interactions suggest a mechanism explaining why A3G exhibits a 3' to 5' directional preference in processive deamination.
Collapse
Affiliation(s)
- Atanu Maiti
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Wazo Myint
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Krista A Delviks-Frankenberry
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD 21702, USA
| | - Shurong Hou
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Tapan Kanai
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA; Department of Chemistry, Banasthali University, Banasthali 304022, Rajasthan, India
| | | | | | - Rashmi Tripathi
- Department of Bioscience and Biotechnology, Banasthali University, Banasthali 304022, Rajasthan, India
| | - Nese Kurt Yilmaz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Vinay K Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD 21702, USA
| | - Celia A Schiffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Hiroshi Matsuo
- Basic Science Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA.
| |
Collapse
|
42
|
Jaguva Vasudevan AA, Balakrishnan K, Gertzen CGW, Borvető F, Zhang Z, Sangwiman A, Held U, Küstermann C, Banerjee S, Schumann GG, Häussinger D, Bravo IG, Gohlke H, Münk C. Loop 1 of APOBEC3C Regulates its Antiviral Activity against HIV-1. J Mol Biol 2020; 432:6200-6227. [PMID: 33068636 DOI: 10.1016/j.jmb.2020.10.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 10/09/2020] [Accepted: 10/09/2020] [Indexed: 01/10/2023]
Abstract
APOBEC3 deaminases (A3s) provide mammals with an anti-retroviral barrier by catalyzing dC-to-dU deamination on viral ssDNA. Within primates, A3s have undergone a complex evolution via gene duplications, fusions, arms race, and selection. Human APOBEC3C (hA3C) efficiently restricts the replication of viral infectivity factor (vif)-deficient Simian immunodeficiency virus (SIVΔvif), but for unknown reasons, it inhibits HIV-1Δvif only weakly. In catarrhines (Old World monkeys and apes), the A3C loop 1 displays the conserved amino acid pair WE, while the corresponding consensus sequence in A3F and A3D is the largely divergent pair RK, which is also the inferred ancestral sequence for the last common ancestor of A3C and of the C-terminal domains of A3D and A3F in primates. Here, we report that modifying the WE residues in hA3C loop 1 to RK leads to stronger interactions with substrate ssDNA, facilitating catalytic function, which results in a drastic increase in both deamination activity and in the ability to restrict HIV-1 and LINE-1 replication. Conversely, the modification hA3F_WE resulted only in a marginal decrease in HIV-1Δvif inhibition. We propose that the two series of ancestral gene duplications that generated A3C, A3D-CTD and A3F-CTD allowed neo/subfunctionalization: A3F-CTD maintained the ancestral RK residues in loop 1, while diversifying selection resulted in the RK → WE modification in Old World anthropoids' A3C, possibly allowing for novel substrate specificity and function.
Collapse
Affiliation(s)
- Ananda Ayyappan Jaguva Vasudevan
- 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; Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, India
| | - Christoph G W Gertzen
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany; John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre & Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich GmbH, Jülich, Germany; Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Fanni Borvető
- Centre National de la Recherche Scientifique, Laboratory MIVEGEC (CNRS, IRD, Uni Montpellier), Montpellier, France
| | - Zeli Zhang
- 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
| | - Ulrike Held
- Division of Medical Biotechnology, Paul-Ehrlich-Institute, Langen, Germany
| | | | - Sharmistha Banerjee
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, India
| | - Gerald G Schumann
- Division of Medical Biotechnology, Paul-Ehrlich-Institute, Langen, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ignacio G Bravo
- Centre National de la Recherche Scientifique, Laboratory MIVEGEC (CNRS, IRD, Uni Montpellier), Montpellier, France
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany; John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre & Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
| |
Collapse
|
43
|
Brezgin S, Kostyusheva A, Ponomareva N, Volia V, Goptar I, Nikiforova A, Shilovskiy I, Smirnov V, Kostyushev D, Chulanov V. Clearing of Foreign Episomal DNA from Human Cells by CRISPRa-Mediated Activation of Cytidine Deaminases. Int J Mol Sci 2020; 21:ijms21186865. [PMID: 32962129 PMCID: PMC7557733 DOI: 10.3390/ijms21186865] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/07/2020] [Accepted: 09/16/2020] [Indexed: 02/06/2023] Open
Abstract
Restriction of foreign DNA is a fundamental defense mechanism required for maintaining genomic stability and proper function of mammalian cells. APOBEC cytidine deaminases are crucial effector molecules involved in clearing pathogenic DNA of viruses and other microorganisms and improperly localized self-DNA (DNA leakages). Mastering the expression of APOBEC provides the crucial means both for developing novel therapeutic approaches for combating infectious and non-infectious diseases and for numerous research purposes. In this study, we report successful application of a CRISPRa approach to effectively and specifically overexpress APOBEC3A and APOBEC3B deaminases and describe their effects on episomal and integrated foreign DNA. This method increased target gene transcription by >6–50-fold in HEK293T cells. Furthermore, CRISPRa-mediated activation of APOBEC3A/APOBEC3B suppressed episomal but not integrated foreign DNA. Episomal GC-rich DNA was rapidly destabilized and destroyed by CRISPRa-induced APOBEC3A/APOBEC3B, while the remaining DNA templates harbored frequent deaminated nucleotides. To conclude, the CRISPRa approach could be readily utilized for manipulating innate immunity and investigating the effects of the key effector molecules on foreign nucleic acids.
Collapse
Affiliation(s)
- Sergey Brezgin
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
- Department of Molecular Immunology, Institute of Immunology, Federal Medical Biological Agency, 115522 Moscow, Russia; (I.S.); (V.S.)
| | - Anastasiya Kostyusheva
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
| | - Natalia Ponomareva
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
| | - Viktoriia Volia
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
| | - Irina Goptar
- Izmerov Research Institute of Occupational Health, 105275 Moscow, Russia; (I.G.); (A.N.)
| | - Anastasiya Nikiforova
- Izmerov Research Institute of Occupational Health, 105275 Moscow, Russia; (I.G.); (A.N.)
| | - Igor Shilovskiy
- Department of Molecular Immunology, Institute of Immunology, Federal Medical Biological Agency, 115522 Moscow, Russia; (I.S.); (V.S.)
| | - Valery Smirnov
- Department of Molecular Immunology, Institute of Immunology, Federal Medical Biological Agency, 115522 Moscow, Russia; (I.S.); (V.S.)
| | - Dmitry Kostyushev
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
- Correspondence:
| | - Vladimir Chulanov
- Department of Molecular Biology and Immunopathology of Infectious Diseases, National Medical Research Center for Tuberculosis and Infectious Diseases, 127994 Moscow, Russia; (S.B.); (A.K.); (N.P.); (V.V.); (V.C.)
- Department of Infectious Diseases, Sechenov First Moscow State Medical University, 119146 Moscow, Russia
| |
Collapse
|
44
|
Delviks-Frankenberry KA, Desimmie BA, Pathak VK. Structural Insights into APOBEC3-Mediated Lentiviral Restriction. Viruses 2020; 12:E587. [PMID: 32471198 PMCID: PMC7354603 DOI: 10.3390/v12060587] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/22/2020] [Accepted: 05/24/2020] [Indexed: 01/18/2023] Open
Abstract
Mammals have developed clever adaptive and innate immune defense mechanisms to protect against invading bacterial and viral pathogens. Human innate immunity is continuously evolving to expand the repertoire of restriction factors and one such family of intrinsic restriction factors is the APOBEC3 (A3) family of cytidine deaminases. The coordinated expression of seven members of the A3 family of cytidine deaminases provides intrinsic immunity against numerous foreign infectious agents and protects the host from exogenous retroviruses and endogenous retroelements. Four members of the A3 proteins-A3G, A3F, A3H, and A3D-restrict HIV-1 in the absence of virion infectivity factor (Vif); their incorporation into progeny virions is a prerequisite for cytidine deaminase-dependent and -independent activities that inhibit viral replication in the host target cell. HIV-1 encodes Vif, an accessory protein that antagonizes A3 proteins by targeting them for polyubiquitination and subsequent proteasomal degradation in the virus producing cells. In this review, we summarize our current understanding of the role of human A3 proteins as barriers against HIV-1 infection, how Vif overcomes their antiviral activity, and highlight recent structural and functional insights into A3-mediated restriction of lentiviruses.
Collapse
Affiliation(s)
| | | | - Vinay K. Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute at Frederick, Frederick, MD 21702, USA; (K.A.D.-F.); (B.A.D.)
| |
Collapse
|
45
|
Abstract
As a part of the innate immune system, humans encode proteins that inhibit viruses such as HIV-1. These broadly acting antiviral proteins do not protect humans from viral infections because viruses encode proteins that antagonize the host antiviral proteins to evade the innate immune system. One such example of a host antiviral protein is APOBEC3C (A3C), which weakly inhibits HIV-1. Here, we show that we can improve the antiviral activity of A3C by duplicating the DNA sequence to create a synthetic tandem domain and, furthermore, that the proteins thus generated are relatively resistant to the viral antagonist Vif. Together, these data give insights about how nature has evolved a defense against viral pathogens such as HIV. Humans encode proteins, called restriction factors, that inhibit replication of viruses such as HIV-1. The members of one family of antiviral proteins, apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3; shortened here to A3), act by deaminating cytidines to uridines during the reverse transcription reaction of HIV-1. The A3 locus encodes seven genes, named A3A to A3H. These genes have either one or two cytidine deaminase domains, and several of these A3s potently restrict HIV-1. A3C, which has only a single cytidine deaminase domain, however, inhibits HIV-1 only very weakly. We tested novel double domain protein combinations by genetically linking two A3C genes to make a synthetic tandem domain protein. This protein created a “super restriction factor” that had more potent antiviral activity than the native A3C protein, which correlated with increased packaging into virions. Furthermore, disabling one of the active sites of the synthetic tandem domain protein resulted in an even greater increase in the antiviral activity—recapitulating a similar evolution seen in A3F and A3G (double domain A3s that use only a single catalytically active deaminase domain). These A3C tandem domain proteins do not have an increase in mutational activity but instead inhibit formation of reverse transcription products, which correlates with their ability to form large higher-order complexes in cells. Finally, the A3C-A3C super restriction factor largely escaped antagonism by the HIV-1 viral protein Vif.
Collapse
|
46
|
Radwan MO, Takaya D, Koga R, Iwamaru K, Tateishi H, Ali TF, Takaori-Kondo A, Otsuka M, Honma T, Fujita M. Interruption of Vif/Elongin C interaction: In silico and experimental elucidation of the underlying molecular mechanism of benzimidazole-based APOBEC3G stabilizers. Bioorg Med Chem 2020; 28:115409. [DOI: 10.1016/j.bmc.2020.115409] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 02/24/2020] [Accepted: 02/27/2020] [Indexed: 11/26/2022]
|
47
|
McDaniel YZ, Wang D, Love RP, Adolph MB, Mohammadzadeh N, Chelico L, Mansky LM. Deamination hotspots among APOBEC3 family members are defined by both target site sequence context and ssDNA secondary structure. Nucleic Acids Res 2020; 48:1353-1371. [PMID: 31943071 PMCID: PMC7026630 DOI: 10.1093/nar/gkz1164] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 11/27/2019] [Accepted: 12/02/2019] [Indexed: 12/26/2022] Open
Abstract
The human apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3, A3) family member proteins can deaminate cytosines in single-strand (ss) DNA, which restricts human immunodeficiency virus type 1 (HIV-1), retrotransposons, and other viruses such as hepatitis B virus, but can cause a mutator phenotype in many cancers. While structural information exists for several A3 proteins, the precise details regarding deamination target selection are not fully understood. Here, we report the first parallel, comparative analysis of site selection of A3 deamination using six of the seven purified A3 member enzymes, oligonucleotides having 5'TC3' or 5'CT3' dinucleotide target sites, and different flanking bases within diverse DNA secondary structures. A3A, A3F and A3H were observed to have strong preferences toward the TC target flanked by A or T, while all examined A3 proteins did not show a preference for a TC target flanked by a G. We observed that the TC target was strongly preferred in ssDNA regions rather than dsDNA, loop or bulge regions, with flanking bases influencing the degree of preference. CT was also shown to be a potential deamination target. Taken together, our observations provide new insights into A3 enzyme target site selection and how A3 mutagenesis impacts mutation rates.
Collapse
Affiliation(s)
- Yumeng Z McDaniel
- Veterinary Medicine Graduate Program, University of Minnesota, Minneapolis, MN 55455 USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455 USA
| | - Dake Wang
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455 USA
- Pharmacology Graduate Program, University of Minnesota, Minneapolis, MN 55455 USA
| | - Robin P Love
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Madison B Adolph
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Nazanin Mohammadzadeh
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Linda Chelico
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Louis M Mansky
- Veterinary Medicine Graduate Program, University of Minnesota, Minneapolis, MN 55455 USA
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455 USA
- Pharmacology Graduate Program, University of Minnesota, Minneapolis, MN 55455 USA
- Division of Basic Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455 USA
- Department of Microbiology & Immunology, University of Minnesota, Minneapolis, MN 55455 USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455 USA
| |
Collapse
|
48
|
Yang H, Ito F, Wolfe AD, Li S, Mohammadzadeh N, Love RP, Yan M, Zirkle B, Gaba A, Chelico L, Chen XS. Understanding the structural basis of HIV-1 restriction by the full length double-domain APOBEC3G. Nat Commun 2020; 11:632. [PMID: 32005813 PMCID: PMC6994475 DOI: 10.1038/s41467-020-14377-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 12/18/2019] [Indexed: 12/17/2022] Open
Abstract
APOBEC3G, a member of the double-domain cytidine deaminase (CD) APOBEC, binds RNA to package into virions and restrict HIV-1 through deamination-dependent or deamination-independent inhibition. Mainly due to lack of a full-length double-domain APOBEC structure, it is unknown how CD1/CD2 domains connect and how dimerization/multimerization is linked to RNA binding and virion packaging for HIV-1 restriction. We report rhesus macaque A3G structures that show different inter-domain packing through a short linker and refolding of CD2. The A3G dimer structure has a hydrophobic dimer-interface matching with that of the previously reported CD1 structure. A3G dimerization generates a surface with intensified positive electrostatic potentials (PEP) for RNA binding and dimer stabilization. Unexpectedly, mutating the PEP surface and the hydrophobic interface of A3G does not abolish virion packaging and HIV-1 restriction. The data support a model in which only one RNA-binding mode is critical for virion packaging and restriction of HIV-1 by A3G. APOBEC3G (A3G) belongs to the DNA/RNA cytosine deaminase family that plays important roles in innate immunity against HIV and internal retroelements. Here the authors report the structures of two full-length A3G variants that provides insight into domain organization, multimerization, RNA binding, and viral restriction.
Collapse
Affiliation(s)
- Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA
| | - Fumiaki Ito
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA
| | - Aaron D Wolfe
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA.,Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90033, USA.,Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, 90033, USA
| | - Shuxing Li
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA.,Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA, 90089, USA
| | - Nazanin Mohammadzadeh
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Robin P Love
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Maocai Yan
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA.,School of Pharmacy, Jining Medical University, 276800, Rizhao, Shandong, China
| | - Brett Zirkle
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA.,Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90033, USA
| | - Amit Gaba
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Xiaojiang S Chen
- Molecular and Computational Biology, Departments of Biological Sciences, Chemistry, University of Southern California, Los Angeles, CA, 90089, USA. .,Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90033, USA. .,Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, 90033, USA. .,Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA, 90089, USA.
| |
Collapse
|
49
|
Morse M, Naufer MN, Feng Y, Chelico L, Rouzina I, Williams MC. HIV restriction factor APOBEC3G binds in multiple steps and conformations to search and deaminate single-stranded DNA. eLife 2019; 8:e52649. [PMID: 31850845 PMCID: PMC6946564 DOI: 10.7554/elife.52649] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/18/2019] [Indexed: 12/15/2022] Open
Abstract
APOBEC3G (A3G), an enzyme expressed in primates with the potential to inhibit human immunodeficiency virus type 1 (HIV-1) infectivity, is a single-stranded DNA (ssDNA) deoxycytidine deaminase with two domains, a catalytically active, weakly ssDNA binding C-terminal domain (CTD) and a catalytically inactive, strongly ssDNA binding N-terminal domain (NTD). Using optical tweezers, we measure A3G binding a single, long ssDNA substrate under various applied forces to characterize the binding interaction. A3G binds ssDNA in multiple steps and in two distinct conformations, distinguished by degree of ssDNA contraction. A3G stabilizes formation of ssDNA loops, an ability inhibited by A3G oligomerization. Our data suggests A3G securely binds ssDNA through the NTD, while the CTD samples and potentially deaminates the substrate. Oligomerization of A3G stabilizes ssDNA binding but inhibits the CTD's search function. These processes explain A3G's ability to efficiently deaminate numerous sites across a 10,000 base viral genome during the reverse transcription process.
Collapse
Affiliation(s)
- Michael Morse
- Department of PhysicsNortheastern UniversityBostonUnited States
| | - M Nabuan Naufer
- Department of PhysicsNortheastern UniversityBostonUnited States
| | - Yuqing Feng
- Department of Biochemistry, Microbiology and ImmunologyUniversity of SaskatchewanSaskatoonCanada
| | - Linda Chelico
- Department of Biochemistry, Microbiology and ImmunologyUniversity of SaskatchewanSaskatoonCanada
| | - Ioulia Rouzina
- Department of Chemistry and BiochemistryOhio State UniversityColumbusUnited States
| | - Mark C Williams
- Department of PhysicsNortheastern UniversityBostonUnited States
| |
Collapse
|
50
|
Bohn JA, DaSilva J, Kharytonchyk S, Mercedes M, Vosters J, Telesnitsky A, Hatziioannou T, Smith JL. Flexibility in Nucleic Acid Binding Is Central to APOBEC3H Antiviral Activity. J Virol 2019; 93:e01275-19. [PMID: 31578294 PMCID: PMC6880157 DOI: 10.1128/jvi.01275-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 09/23/2019] [Indexed: 11/20/2022] Open
Abstract
APOBEC3 proteins APOBEC3F (A3F), APOBEC3G (A3G), and APOBEC3H (A3H) are host restriction factors that inhibit HIV-1 through DNA cytidine deaminase-dependent and -independent mechanisms and have either one (A3H) or two (A3F and A3G) zinc-binding domains. A3H antiviral activity encompasses multiple molecular functions, all of which depend on recognition of RNA or DNA. A3H crystal structures revealed an unusual interaction with RNA wherein an RNA duplex mediates dimerization of two A3H proteins. In this study, we sought to determine the importance of RNA-binding amino acids in the antiviral and biochemical properties of A3H. We show that the wild-type A3H-RNA interaction is essential for A3H antiviral activity and for two deaminase-independent processes: encapsidation into viral particles and inhibition of reverse transcription. Furthermore, an extensive mutagenesis campaign revealed distinct roles for two groups of amino acids at the RNA binding interface. C-terminal helix residues exclusively bind RNA, and loop 1 residues play a dual role in recognition of DNA substrates and in RNA binding. Weakening the interface between A3H and RNA allows DNA substrates to bind with greater affinity and enhances deamination rates, suggesting that RNA binding must be disrupted to accommodate DNA. Intriguingly, we demonstrate that A3H can deaminate overhanging DNA strands of RNA/DNA heteroduplexes, which are early intermediates during reverse transcription and may represent natural A3H substrates. Overall, we present a mechanistic model of A3H restriction and a step-by-step elucidation of the roles of RNA-binding residues in A3H activity, particle incorporation, inhibition of reverse transcriptase inhibition, and DNA cytidine deamination.IMPORTANCE APOBEC3 proteins are host factors that protect the integrity of the host genome by inhibiting retroelements as well as retroviruses, such as HIV-1. To do this, the APOBEC3H protein has evolved unique interactions with structured RNAs. Here, we studied the importance of these interactions in driving antiviral activity of APOBEC3H. Our results provide a clear picture of how RNA binding drives the ability of APOBEC3H to infiltrate new viruses and prevent synthesis of viral DNA. We also explore how RNA binding by APOBEC3H influences recognition and deamination of viral DNA and describe two possible routes by which APOBEC3H might hypermutate the HIV-1 genome. These results highlight how one protein can sense many nucleic acid species for a variety of antiviral activities.
Collapse
Affiliation(s)
- Jennifer A Bohn
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Justin DaSilva
- Laboratory of Retrovirology, The Rockefeller University, New York, New York, USA
| | - Siarhei Kharytonchyk
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Maria Mercedes
- Laboratory of Retrovirology, The Rockefeller University, New York, New York, USA
| | - Jennifer Vosters
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - Alice Telesnitsky
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Janet L Smith
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|