1
|
Budzko L, Hoffa-Sobiech K, Jackowiak P, Figlerowicz M. Engineered deaminases as a key component of DNA and RNA editing tools. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 34:102062. [PMID: 38028200 PMCID: PMC10661471 DOI: 10.1016/j.omtn.2023.102062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Over recent years, zinc-dependent deaminases have attracted increasing interest as key components of nucleic acid editing tools that can generate point mutations at specific sites in either DNA or RNA by combining a targeting module (such as a catalytically impaired CRISPR-Cas component) and an effector module (most often a deaminase). Deaminase-based molecular tools are already being utilized in a wide spectrum of therapeutic and research applications; however, their medical and biotechnological potential seems to be much greater. Recent reports indicate that the further development of nucleic acid editing systems depends largely on our ability to engineer the substrate specificity and catalytic activity of the editors themselves. In this review, we summarize the current trends and achievements in deaminase engineering. The presented data indicate that the potential of these enzymes has not yet been fully revealed or understood. Several examples show that even relatively minor changes in the structure of deaminases can give them completely new and unique properties.
Collapse
Affiliation(s)
- Lucyna Budzko
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Karolina Hoffa-Sobiech
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Paulina Jackowiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Marek Figlerowicz
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| |
Collapse
|
2
|
Ranga A, Gupta A, Yadav L, Kumar S, Jain P. Advancing beyond reverse transcriptase inhibitors: The new era of hepatitis B polymerase inhibitors. Eur J Med Chem 2023; 257:115455. [PMID: 37216809 DOI: 10.1016/j.ejmech.2023.115455] [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: 02/28/2023] [Revised: 05/03/2023] [Accepted: 05/03/2023] [Indexed: 05/24/2023]
Abstract
Hepatitis B virus (HBV) is a genetically diverse blood-borne virus responsible for chronic hepatitis B. The HBV polymerase plays a key role in viral genome replication within the human body and has been identified as a potential drug target for chronic hepatitis B therapeutics. However, available nucleotide reverse transcriptase inhibitors only target the reverse transcriptase domain of the HBV polymerase; they also pose resistance issues and require lifelong treatment that can burden patients financially. In this study, various chemical classes are reviewed that have been developed to target different domains of the HBV polymerase: Terminal protein, which plays a vital role in the formation of the viral DNA; Reverse transcriptase, which is responsible for the synthesis of the viral DNA from RNA, and; Ribonuclease H, which is responsible for degrading the RNA strand in the RNA-DNA duplex formed during the reverse transcription process. Host factors that interact with the HBV polymerase to achieve HBV replication are also reviewed; these host factors can be targeted by inhibitors to indirectly inhibit polymerase functionality. A detailed analysis of the scope and limitations of these inhibitors from a medicinal chemistry perspective is provided. The structure-activity relationship of these inhibitors and the factors that may affect their potency and selectivity are also examined. This analysis will be useful in supporting the further development of these inhibitors and in designing new inhibitors that can inhibit HBV replication more efficiently.
Collapse
Affiliation(s)
- Abhishek Ranga
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Aarti Gupta
- Department of Pharmaceutical Biotechnology, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Laxmi Yadav
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Sachin Kumar
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India.
| | - Priti Jain
- Department of Pharmaceutical Chemistry, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India.
| |
Collapse
|
3
|
Zhang Y, Chen X, Cao Y, Yang Z. Roles of APOBEC3 in hepatitis B virus (HBV) infection and hepatocarcinogenesis. Bioengineered 2021; 12:2074-2086. [PMID: 34043485 PMCID: PMC8806738 DOI: 10.1080/21655979.2021.1931640] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/12/2021] [Accepted: 05/13/2021] [Indexed: 02/08/2023] Open
Abstract
APOBEC3 (A3) cytidine deaminases inhibit hepatitis B virus (HBV) infection and play vital roles in maintaining a variety of biochemical processes, including the regulation of protein expression and innate immunity. Emerging evidence indicates that the deaminated deoxycytidine biochemical activity of A3 proteins in single-stranded DNA makes them a double-edged sword. These enzymes can cause cellular genetic mutations at replication forks or within transcription bubbles, depending on the physiological state of the cell and the phase of the cell cycle. Under pathological conditions, aberrant expression of A3 genes with improper deaminase activity regulation may threaten genomic stability and eventually lead to cancer development. This review attempted to summarize the antiviral activities and underlying mechanisms of A3 editing enzymes in HBV infections. Moreover, the correlations between A3 genes and hepatocarcinogenesis were also elucidated.
Collapse
Affiliation(s)
- Yuan Zhang
- Department of Integrative Medicine, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Xiaorong Chen
- Department of Integrative Medicine, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yajuan Cao
- Central Laboratory, Shanghai Pulmonary HospitalSchool of Medicine, Tongji University School of Medicine, Shanghai, China
- Clinical Translation Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Zongguo Yang
- Department of Integrative Medicine, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| |
Collapse
|
4
|
Potential APOBEC-mediated RNA editing of the genomes of SARS-CoV-2 and other coronaviruses and its impact on their longer term evolution. Virology 2021; 556:62-72. [PMID: 33545556 PMCID: PMC7831814 DOI: 10.1016/j.virol.2020.12.018] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/21/2020] [Accepted: 12/21/2020] [Indexed: 12/19/2022]
Abstract
Members of the APOBEC family of cytidine deaminases show antiviral activities in mammalian cells through lethal editing in the genomes of small DNA viruses, herpesviruses and retroviruses, and potentially those of RNA viruses such as coronaviruses. Consistent with the latter, APOBEC-like directional C→U transitions of genomic plus-strand RNA are greatly overrepresented in SARS-CoV-2 genome sequences of variants emerging during the COVID-19 pandemic. A C→U mutational process may leave evolutionary imprints on coronavirus genomes, including extensive homoplasy from editing and reversion at targeted sites and the occurrence of driven amino acid sequence changes in viral proteins. If sustained over longer periods, this process may account for the previously reported marked global depletion of C and excess of U bases in human seasonal coronavirus genomes. This review synthesizes the current knowledge on APOBEC evolution and function and the evidence of their role in APOBEC-mediated genome editing of SARS-CoV-2 and other coronaviruses. SARS-CoV-2 sequence variants contain an overabundance of C- > U transitions C- > U transitions are the hallmark of the activity of APOBEC cytosine deaminases Further work is needed to determine APOBEC's role in coronavirus evolution
Collapse
|
5
|
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
|
6
|
Caval V, Jiao W, Berry N, Khalfi P, Pitré E, Thiers V, Vartanian JP, Wain-Hobson S, Suspène R. Mouse APOBEC1 cytidine deaminase can induce somatic mutations in chromosomal DNA. BMC Genomics 2019; 20:858. [PMID: 31726973 PMCID: PMC6854741 DOI: 10.1186/s12864-019-6216-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 10/22/2019] [Indexed: 02/06/2023] Open
Abstract
Background APOBEC1 (A1) enzymes are cytidine deaminases involved in RNA editing. In addition to this activity, a few A1 enzymes have been shown to be active on single stranded DNA. As two human ssDNA cytidine deaminases APOBEC3A (A3A), APOBEC3B (A3B) and related enzymes across the spectrum of placental mammals have been shown to introduce somatic mutations into nuclear DNA of cancer genomes, we explored the mutagenic threat of A1 cytidine deaminases to chromosomal DNA. Results Molecular cloning and expression of various A1 enzymes reveal that the cow, pig, dog, rabbit and mouse A1 have an intracellular ssDNA substrate specificity. However, among all the enzymes studied, mouse A1 appears to be singular, being able to introduce somatic mutations into nuclear DNA with a clear 5’TpC editing context, and to deaminate 5-methylcytidine substituted DNA which are characteristic features of the cancer related mammalian A3A and A3B enzymes. However, mouse A1 activity fails to elicit formation of double stranded DNA breaks, suggesting that mouse A1 possess an attenuated nuclear DNA mutator phenotype reminiscent of human A3B. Conclusions At an experimental level mouse APOBEC1 is remarkable among 12 mammalian A1 enzymes in that it represents a source of somatic mutations in mouse genome, potentially fueling oncogenesis. While the order Rodentia is bereft of A3A and A3B like enzymes it seems that APOBEC1 may well substitute for it, albeit remaining much less active. This modifies the paradigm that APOBEC3 and AID enzymes are the sole endogenous mutator enzymes giving rise to off-target editing of mammalian genomes.
Collapse
Affiliation(s)
- Vincent Caval
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.
| | - Wenjuan Jiao
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Noémie Berry
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Pierre Khalfi
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Emmanuelle Pitré
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France.,Sorbonne Université, Complexité du Vivant, ED515, 75005, Paris, France
| | - Valérie Thiers
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Jean-Pierre Vartanian
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Simon Wain-Hobson
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| | - Rodolphe Suspène
- Molecular Retrovirology Unit, Institut Pasteur, CNRS UMR 3569, 28 rue du Dr. Roux, 75724, Paris cedex 15, France
| |
Collapse
|
7
|
Michalski D, Ontiveros JG, Russo J, Charley PA, Anderson JR, Heck AM, Geiss BJ, Wilusz J. Zika virus noncoding sfRNAs sequester multiple host-derived RNA-binding proteins and modulate mRNA decay and splicing during infection. J Biol Chem 2019; 294:16282-16296. [PMID: 31519749 DOI: 10.1074/jbc.ra119.009129] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 08/19/2019] [Indexed: 12/17/2022] Open
Abstract
Insect-borne flaviviruses produce a 300-500-base long noncoding RNA, termed subgenomic flavivirus RNA (sfRNA), by stalling the cellular 5'-3'-exoribonuclease 1 (XRN1) via structures located in their 3' UTRs. In this study, we demonstrate that sfRNA production by Zika virus represses XRN1 analogous to what we have previously shown for other flaviviruses. Using protein-RNA reconstitution and a stringent RNA pulldown assay with human choriocarcinoma (JAR) cells, we demonstrate that the sfRNAs from both dengue type 2 and Zika viruses interact with a common set of 21 RNA-binding proteins that contribute to the regulation of post-transcriptional processes in the cell, including splicing, RNA stability, and translation. We found that four of these sfRNA-interacting host proteins, DEAD-box helicase 6 (DDX6) and enhancer of mRNA decapping 3 (EDC3) (two RNA decay factors), phosphorylated adaptor for RNA export (a regulator of the biogenesis of the splicing machinery), and apolipoprotein B mRNA-editing enzyme catalytic subunit 3C (APOBEC3C, a nucleic acid-editing deaminase), inherently restrict Zika virus infection. Furthermore, we demonstrate that the regulations of cellular mRNA decay and RNA splicing are compromised by Zika virus infection as well as by sfRNA alone. Collectively, these results reveal the large extent to which Zika virus-derived sfRNAs interact with cellular RNA-binding proteins and highlight the potential for widespread dysregulation of post-transcriptional control that likely limits the effective response of these cells to viral infection.
Collapse
Affiliation(s)
- Daniel Michalski
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523
| | - J Gustavo Ontiveros
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523
| | - Joseph Russo
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523
| | - Phillida A Charley
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523
| | - John R Anderson
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523
| | - Adam M Heck
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523
| | - Brian J Geiss
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523.,Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523
| | - Jeffrey Wilusz
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523 .,Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado 80523
| |
Collapse
|
8
|
Ren F, Li W, Xiang A, Wang L, Li M, Guo Y. Distribution and difference of APOBEC-induced mutations in the TpCpW context of HBV DNA between HCC and non-HCC. J Med Virol 2019; 92:53-61. [PMID: 31429946 DOI: 10.1002/jmv.25572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 08/10/2019] [Indexed: 12/30/2022]
Abstract
Hepatitis B virus (HBV) DNA is vulnerable to editing by human apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) cytidine deaminases. However, the distribution of APOBEC-induced mutations on HBV DNA is not well characterized. To this end, we obtained the HBV DNA sequence of HBV-infected individuals with and without hepatocellular carcinoma (HCC and non-HCC groups, respectively) from NCBI database and calculated the rapo values of APOBEC-induced TpCpW→TpKpW mutation prevalence in HBV DNA. The results showed that the APOBEC-induced mutations were mainly distributed in the minus strand of non-HCC-derived HBV DNA (rapo = 2.04), while the mutation on the plus-strand was weaker (rapo = 0.99). There were high APOBEC-induced mutation regions in the minus strand of HBV DNA 1 to 1000 nucleotides (nts) region and in the plus-strand of HBV DNA 1000 to 1500 nts region; the mutations in the 1 to 1000 nts region were mainly TpCpW→TpTpW mutation types (total T/G: 111/18) and a number of these were missense mutations (missense/synonymous: 35/94 in P gene, 17/15 in S gene, and 5/10 in X gene). The difference between minus to plus-strand rapo of HCC-derived HBV DNA (1.96) was greater than that of the non-HCC group (1.05). The minus-strand rapo of HCC-derived HBV DNA regions 1000 to1500nts and 1500 to 2000 nts (rapo = 4.2 and 4.2) was also higher than that of the same regions of non-HCC-derived HBV DNA (rapo = 1.2 and 1.1). Finally, the ratio of minus to plus-strand rapo was used to distinguish HCC-derived HBV DNA from non-HCC-derived HBV DNA. This study unraveled the distribution characteristics of APOBEC-induced mutations on double strands of HBV DNA from HCC and non-HCC samples. Our findings would help understand the mechanism of APOBECs on HBV DNA and may provide important insights for the screening of HCC.
Collapse
Affiliation(s)
- FengLing Ren
- Department of Environmental and Occupational Health, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - WeiNa Li
- Department of Biopharmaceutics, Air Force Military Medical University, Xi'an, Shaanxi, China
| | - An Xiang
- Department of Biopharmaceutics, Air Force Military Medical University, Xi'an, Shaanxi, China
| | - Li Wang
- Department of Biopharmaceutics, Air Force Military Medical University, Xi'an, Shaanxi, China
| | - Meng Li
- Department of Biopharmaceutics, Air Force Military Medical University, Xi'an, Shaanxi, China
| | - YanHai Guo
- Department of Biopharmaceutics, Air Force Military Medical University, Xi'an, Shaanxi, China
| |
Collapse
|
9
|
Lerner T, Papavasiliou FN, Pecori R. RNA Editors, Cofactors, and mRNA Targets: An Overview of the C-to-U RNA Editing Machinery and Its Implication in Human Disease. Genes (Basel) 2018; 10:E13. [PMID: 30591678 PMCID: PMC6356216 DOI: 10.3390/genes10010013] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 12/10/2018] [Accepted: 12/20/2018] [Indexed: 12/22/2022] Open
Abstract
One of the most prevalent epitranscriptomic modifications is RNA editing. In higher eukaryotes, RNA editing is catalyzed by one of two classes of deaminases: ADAR family enzymes that catalyze A-to-I (read as G) editing, and AID/APOBEC family enzymes that catalyze C-to-U. ADAR-catalyzed deamination has been studied extensively. Here we focus on AID/APOBEC-catalyzed editing, and review the emergent knowledge regarding C-to-U editing consequences in the context of human disease.
Collapse
Affiliation(s)
- Taga Lerner
- Division of Immune Diversity, Program in Cancer Immunology, German Cancer Research Centre, 69120 Heidelberg, Germany.
- Division of Biosciences, Uni Heidelberg, 69120 Heidelberg, Germany.
| | - F Nina Papavasiliou
- Division of Immune Diversity, Program in Cancer Immunology, German Cancer Research Centre, 69120 Heidelberg, Germany.
| | - Riccardo Pecori
- Division of Immune Diversity, Program in Cancer Immunology, German Cancer Research Centre, 69120 Heidelberg, Germany.
| |
Collapse
|
10
|
Wu L, Yao Q, Lin P, Li Y, Li H. Comparative transcriptomics reveals specific responding genes associated with atherosclerosis in rabbit and mouse models. PLoS One 2018; 13:e0201618. [PMID: 30067832 PMCID: PMC6070260 DOI: 10.1371/journal.pone.0201618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 07/18/2018] [Indexed: 11/18/2022] Open
Abstract
Mouse and rabbit are frequently employed species for atherosclerosis research. With respect to modeling human atherosclerosis, it has been observed that variations in phenotype under commonly used atherogenic conditions are partial or no congruence between two species. However, genome-wide molecular variations are still lacking. To understand the differences between rabbit and mouse in developing atherosclerosis, here from aspect of orthologs, we compared the genome-wide expression profiles of two species under the same atherosclerosis driven factors: high-fat diet or LDLR deficiency. Our results illuminated that: 1) LDLR-deficiency induced different gene expression changes in rabbit and mouse. WHHL rabbit had more significantly differential expressed genes and the most of genes were down-regulated. 2) Some genes and functions were commonly dysregulated in high-fat fed rabbit and mouse models, such as lipid metabolism and inflammation process. However, high-fat intake in rabbit produced more differentially expressed genes and more serious functional effects. 3) Specific differential expression genes were revealed for rabbit and mouse related with high-fat intake. In the aspect of lipoprotein metabolism, APOA4 and APOB was the major responding gene in rabbit and mice, respectively. The expression change of APOA4 and APOB in human atherosclerosis was more similar to rabbit, and therefore rabbit might be a better animal model for investigating human lipoprotein metabolism related diseases. In conclusion, our comparative transcriptome analysis revealed species-specific expression regulation that could partially explain the different phenotypes between rabbit and mouse, which was helpful for model selection to study atherosclerosis.
Collapse
Affiliation(s)
- Leilei Wu
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Qianlan Yao
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Ping Lin
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yixue Li
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
- Collaborative Innovation Center of Genetics and Development, Fudan University, Shanghai, China
| | - Hong Li
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| |
Collapse
|
11
|
Ortega-Prieto AM, Dorner M. Immune Evasion Strategies during Chronic Hepatitis B and C Virus Infection. Vaccines (Basel) 2017; 5:E24. [PMID: 28862649 PMCID: PMC5620555 DOI: 10.3390/vaccines5030024] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 08/25/2017] [Accepted: 08/30/2017] [Indexed: 12/15/2022] Open
Abstract
Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are a major global healthcare problem with more than 240 million and 70 million infected, respectively. Both viruses persist within the liver and result in progressive liver disease, resulting in liver fibrosis, cirrhosis and hepatocellular carcinoma. Strikingly, this pathogenesis is largely driven by immune responses, unable to clear an established infection, rather than by the viral pathogens themselves. Even though disease progression is very similar in both infections, HBV and HCV have evolved distinct mechanisms, by which they ensure persistence within the host. Whereas HCV utilizes a cloak-and-dagger approach, disguising itself as a lipid-like particle and immediately crippling essential pattern-recognition pathways, HBV has long been considered a "stealth" virus, due to the complete absence of innate immune responses during infection. Recent developments and access to improved model systems, however, revealed that even though it is among the smallest human-tropic viruses, HBV may, in addition to evading host responses, employ subtle immune evasion mechanisms directed at ensuring viral persistence in the absence of host responses. In this review, we compare the different strategies of both viruses to ensure viral persistence by actively interfering with viral recognition and innate immune responses.
Collapse
Affiliation(s)
| | - Marcus Dorner
- Section of Virology, Department of Medicine, Imperial College London, London W2 1PG, UK.
| |
Collapse
|
12
|
Ito F, Fu Y, Kao SCA, Yang H, Chen XS. Family-Wide Comparative Analysis of Cytidine and Methylcytidine Deamination by Eleven Human APOBEC Proteins. J Mol Biol 2017; 429:1787-1799. [PMID: 28479091 DOI: 10.1016/j.jmb.2017.04.021] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 04/28/2017] [Accepted: 04/29/2017] [Indexed: 01/17/2023]
Abstract
Apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) proteins are a family of cytidine deaminases involved in various important biological processes such as antibody diversification/maturation, restriction of viral infection, and generation of somatic mutations. Catalytically active APOBEC proteins execute their biological functions mostly through deaminating cytosine (C) to uracil on single-stranded DNA/RNA. Activation-induced cytidine deaminase, one of the APOBEC members, was reported to deaminate methylated cytosine (mC) on DNA, and this mC deamination was proposed to be involved in the demethylation of mC for epigenetic regulation. The mC deamination activity is later demonstrated for APOBEC3A (A3A) and more recently for APOBEC3B and APOBEC3H (A3H). Despite extensive studies on APOBEC proteins, questions regarding whether the rest of APOBEC members have any mC deaminase activity and what are the relative deaminase activities for each APOBEC member remain unclear. Here, we performed a family-wide analysis of deaminase activities on C and mC by using purified recombinant proteins for 11 known human APOBEC proteins under similar conditions. Our comprehensive analyses revealed that each APOBEC has unique deaminase activity and selectivity for mC. A3A and A3H showed distinctively high deaminase activities on C and mC with relatively high selectivity for mC, whereas six other APOBEC members showed relatively low deaminase activity and selectivity for mC. Our mutational analysis showed that loop-1 of A3A is responsible for its high deaminase activity and selectivity for mC. These findings extend our understanding of APOBEC family proteins that have important roles in diverse biological functions and in genetic mutations.
Collapse
Affiliation(s)
- Fumiaki Ito
- Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Yang Fu
- Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Shen-Chi A Kao
- Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Hanjing Yang
- Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Xiaojiang S Chen
- Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA; Department of Chemistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA; Center of Excellence in NanoBiophysics, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA.
| |
Collapse
|
13
|
Opossum APOBEC1 is a DNA mutator with retrovirus and retroelement restriction activity. Sci Rep 2017; 7:46719. [PMID: 28429755 PMCID: PMC5399452 DOI: 10.1038/srep46719] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 03/23/2017] [Indexed: 01/12/2023] Open
Abstract
APOBEC3s (A3s) are single-stranded DNA cytosine deaminases that provide innate immune defences against retroviruses and mobile elements. A3s are specific to eutherian mammals because no direct homologs exist at the syntenic genomic locus in metatherian (marsupial) or prototherian (monotreme) mammals. However, the A3s in these species have the likely evolutionary precursors, the antibody gene deaminase AID and the RNA/DNA editing enzyme APOBEC1 (A1). Here, we used cell culture-based assays to determine whether opossum A1 restricts the infectivity of retroviruses including human immunodeficiency virus type 1 (HIV-1) and the mobility of LTR/non-LTR retrotransposons. Opossum A1 partially inhibited HIV-1, as well as simian immunodeficiency virus (SIV), murine leukemia virus (MLV), and the retrotransposon MusD. The mechanism of inhibition required catalytic activity, except for human LINE1 (L1) restriction, which was deamination-independent. These results indicate that opossum A1 functions as an innate barrier to infection by retroviruses such as HIV-1, and controls LTR/non-LTR retrotransposition in marsupials.
Collapse
|
14
|
Creation of chimeric human/rabbit APOBEC1 with HIV-1 restriction and DNA mutation activities. Sci Rep 2016; 6:19035. [PMID: 26738439 PMCID: PMC4704027 DOI: 10.1038/srep19035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 12/04/2015] [Indexed: 11/17/2022] Open
Abstract
APOBEC1 (A1) proteins from lagomorphs and rodents have deaminase-dependent restriction activity against HIV-1, whereas human A1 exerts a negligible effect. To investigate these differences in the restriction of HIV-1 by A1 proteins, a series of chimeric proteins combining rabbit and human A1s was constructed. Homology models of the A1s indicated that their activities derive from functional domains that likely act in tandem through a dimeric interface. The C-terminal region containing the leucine-rich motif and the dimerization domains of rabbit A1 is important for its anti-HIV-1 activity. The A1 chimeras with strong anti-HIV-1 activity were incorporated into virions more efficiently than those without anti-HIV-1 activity, and exhibited potent DNA-mutator activity. Therefore, the C-terminal region of rabbit A1 is involved in both its packaging into the HIV-1 virion and its deamination activity against both viral cDNA and genomic RNA. This study identifies the novel molecular mechanism underlying the target specificity of A1.
Collapse
|
15
|
He X, Li J, Wu J, Zhang M, Gao P. Associations between activation-induced cytidine deaminase/apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like cytidine deaminase expression, hepatitis B virus (HBV) replication and HBV-associated liver disease (Review). Mol Med Rep 2015; 12:6405-14. [PMID: 26398702 PMCID: PMC4626158 DOI: 10.3892/mmr.2015.4312] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 08/25/2015] [Indexed: 12/12/2022] Open
Abstract
The hepatitis B virus (HBV) infection is a major risk factor in the development of chronic hepatitis (CH) and hepa-tocellular carcinoma (HCC). The activation-induced cytidine deaminase (AID)/apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) family of cytidine deaminases is significant in innate immunity, as it restricts numerous viruses, including HBV, through hypermutation-dependent and -independent mechanisms. It is important to induce covalently closed circular (ccc)DNA degradation by interferon-α without causing side effects in the infected host cell. Furthermore, organisms possess multiple mechanisms to regulate the expression of AID/APOBECs, control their enzymatic activity and restrict their access to DNA or RNA substrates. Therefore, the AID/APOBECs present promising targets for preventing and treating viral infections. In addition, gene polymorphisms of the AID/APOBEC family may alter host susceptibility to HBV acquisition and CH disease progression. Through G-to-A hypermutation, AID/APOBECs also edit HBV DNA and facilitate the mutation of HBV DNA, which may assist the virus to evolve and potentially escape from the immune responses. The AID/APOBEC family and their associated editing patterns may also exert oncogenic activity. Understanding the effects of cytidine deaminases in CH virus-induced hepatocarcinogenesis may aid with developing efficient prophylactic and therapeutic strategies against HCC.
Collapse
Affiliation(s)
- Xiuting He
- Department of Geriatrics, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jie Li
- Department of Geriatrics, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jing Wu
- Department of Geriatrics, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Manli Zhang
- Department of Gastroenterology, The Second Branch of The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Pujun Gao
- Department of Hepatology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| |
Collapse
|
16
|
Ji X, Zhang Q, Du Y, Liu W, Li Z, Hou X, Cao G. Somatic mutations, viral integration and epigenetic modification in the evolution of hepatitis B virus-induced hepatocellular carcinoma. Curr Genomics 2015; 15:469-80. [PMID: 25646075 PMCID: PMC4311391 DOI: 10.2174/1389202915666141114213833] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 11/11/2014] [Accepted: 11/14/2014] [Indexed: 02/08/2023] Open
Abstract
Liver cancer in men is the second leading cause of cancer death and hepatocellular carcinoma (HCC) accounts for 70%-85% of the total liver cancer worldwide. Chronic infection with hepatitis B virus (HBV) is the major cause of HCC. Chronic, intermittently active inflammation provides “fertile field” for “mutation, selection, and adaptation” of HBV and the infected hepatocytes, a long-term evolutionary process during HBV-induced carcinogenesis. HBV mutations, which are positively selected by insufficient immunity, can promote and predict the occurrence of HCC. Recently, advanced sequencing technologies including whole genome sequencing, exome sequencing, and RNA sequencing provide opportunities to better under-stand the insight of how somatic mutations, structure variations, HBV integrations, and epigenetic modifications contribute to HCC development. Genomic variations of HCC caused by various etiological factors may be different, but the common driver mutations are important to elucidate the HCC evolutionary process. Genome-wide analyses of HBV integrations are helpful in clarifying the targeted genes of HBV in carcinogenesis and disease progression. RNA sequencing can identify key molecules whose expressions are epigenetically modified during HCC evolution. In this review, we summarized the current findings of next generation sequencings for HBV-HCC and proposed a theory framework of Cancer Evolution and Development based on the current knowledge of HBV-induced HCC to characterize and interpret evolutionary mechanisms of HCC and possible other cancers. Understanding the key viral and genomic variations involved in HCC evolution is essential for generating effective diagnostic, prognostic, and predictive biomarkers as well as therapeutic targets for the interventions of HBV-HCC.
Collapse
Affiliation(s)
- Xiaowei Ji
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Qi Zhang
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Yan Du
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Wenbin Liu
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Zixiong Li
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Xiaomei Hou
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| | - Guangwen Cao
- Department of Epidemiology, Second Military Medical University, Shanghai 200433, China
| |
Collapse
|
17
|
Moris A, Murray S, Cardinaud S. AID and APOBECs span the gap between innate and adaptive immunity. Front Microbiol 2014; 5:534. [PMID: 25352838 PMCID: PMC4195361 DOI: 10.3389/fmicb.2014.00534] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 09/24/2014] [Indexed: 12/17/2022] Open
Abstract
The activation-induced deaminase (AID)/APOBEC cytidine deaminases participate in a diversity of biological processes from the regulation of protein expression to embryonic development and host defenses. In its classical role, AID mutates germline-encoded sequences of B cell receptors, a key aspect of adaptive immunity, and APOBEC1, mutates apoprotein B pre-mRNA, yielding two isoforms important for cellular function and plasma lipid metabolism. Investigations over the last ten years have uncovered a role of the APOBEC superfamily in intrinsic immunity against viruses and innate immunity against viral infection by deamination and mutation of viral genomes. Further, discovery in the area of human immunodeficiency virus (HIV) infection revealed that the HIV viral infectivity factor protein interacts with APOBEC3G, targeting it for proteosomal degradation, overriding its antiviral function. More recently, our and others' work have uncovered that the AID and APOBEC cytidine deaminase family members have an even more direct link between activity against viral infection and induction and shaping of adaptive immunity than previously thought, including that of antigen processing for cytotoxic T lymphocyte activity and natural killer cell activation. Newly ascribed functions of these cytodine deaminases will be discussed, including their newly identified roles in adaptive immunity, epigenetic regulation, and cell differentiation. Herein this review we discuss AID and APOBEC cytodine deaminases as a link between innate and adaptive immunity uncovered by recent studies.
Collapse
Affiliation(s)
- Arnaud Moris
- Center for Immunology and Microbial Infections, Faculty of Medicine, Université Paris-Sorbonne UPMC Univ Paris 06, Paris, France ; Center for Immunology and Microbial Infections, Institut National de la Santé et de la Recherche Médicale U1135, Paris, France ; Center for Immunology and Microbial Infections, Centre National de la Recherche Scientifique ERL 8255, Paris, France ; Department of Immunology, Hôpital Pitié-Salpêtière Paris, France
| | - Shannon Murray
- Center for Immunology and Microbial Infections, Faculty of Medicine, Université Paris-Sorbonne UPMC Univ Paris 06, Paris, France ; Center for Immunology and Microbial Infections, Institut National de la Santé et de la Recherche Médicale U1135, Paris, France ; Center for Immunology and Microbial Infections, Centre National de la Recherche Scientifique ERL 8255, Paris, France
| | - Sylvain Cardinaud
- Center for Immunology and Microbial Infections, Faculty of Medicine, Université Paris-Sorbonne UPMC Univ Paris 06, Paris, France ; Center for Immunology and Microbial Infections, Institut National de la Santé et de la Recherche Médicale U1135, Paris, France ; Center for Immunology and Microbial Infections, Centre National de la Recherche Scientifique ERL 8255, Paris, France
| |
Collapse
|
18
|
Barrett BS, Guo K, Harper MS, Li SX, Heilman KJ, Davidson NO, Santiago ML. Reassessment of murine APOBEC1 as a retrovirus restriction factor in vivo. Virology 2014; 468-470:601-608. [PMID: 25303118 DOI: 10.1016/j.virol.2014.09.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 09/02/2014] [Accepted: 09/06/2014] [Indexed: 12/21/2022]
Abstract
APOBEC1 is a cytidine deaminase involved in cholesterol metabolism that has been linked to retrovirus restriction, analogous to the evolutionarily-related APOBEC3 proteins. In particular, murine APOBEC1 was shown to inhibit Friend retrovirus (FV) in vitro, generating high levels of C-to-T and G-to-A mutations. These observations raised the possibility that FV infection might be altered in APOBEC1-null mice. To examine this question directly, we infected wild-type and APOBEC1-null mice with FV complex and evaluated acute infection levels. Surprisingly, APOBEC1-null mice exhibited similar cellular infection levels and plasma viremia relative to wild-type mice. Moreover, next-generation sequencing analyses revealed that in contrast to APOBEC3, APOBEC1 did not enhance retroviral C-to-T and G-to-A mutational frequencies in genomic DNA. Thus, APOBEC1 neither inhibited nor significantly drove the molecular evolution of FV in vivo. Our findings reinforce that not all retrovirus restriction factors characterized as potent in vitro may be functionally relevant in vivo.
Collapse
Affiliation(s)
- Bradley S Barrett
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - Kejun Guo
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - Michael S Harper
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA; Department of Immunology and Microbiology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Sam X Li
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA; Department of Immunology and Microbiology, University of Colorado Denver, Aurora, CO 80045, USA
| | - Karl J Heilman
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - Nicholas O Davidson
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Mario L Santiago
- Department of Medicine, University of Colorado Denver, Aurora, CO 80045, USA; Department of Immunology and Microbiology, University of Colorado Denver, Aurora, CO 80045, USA.
| |
Collapse
|
19
|
Pei RJ, Chen XW, Lu MJ. Control of hepatitis B virus replication by interferons and Toll-like receptor signaling pathways. World J Gastroenterol 2014; 20:11618-11629. [PMID: 25206268 PMCID: PMC4155354 DOI: 10.3748/wjg.v20.i33.11618] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/23/2013] [Accepted: 04/16/2014] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is one of the major causes of liver diseases, affecting more than 350 million people worldwide. The interferon (IFN)-mediated innate immune responses could restrict HBV replication at the different steps of viral life cycle. Indeed, IFN-α has been successfully used for treatment of patients with chronic hepatitis B. However, the role of the innate immune response in HBV replication and the mechanism of the anti-HBV effect of IFN-α are not completely explored. In this review, we summarized the currently available knowledge about the IFN-mediated anti-HBV effect in the HBV life cycle and the possible effectors downstream the IFN signaling pathway. The antiviral effect of Toll-like receptors (TLRs) in HBV replication is briefly discussed. The strategies exploited by HBV to evade the IFN- and TLR-mediated antiviral actions are summarized.
Collapse
|
20
|
Prohaska KM, Bennett RP, Salter JD, Smith HC. The multifaceted roles of RNA binding in APOBEC cytidine deaminase functions. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 5:493-508. [PMID: 24664896 DOI: 10.1002/wrna.1226] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 02/13/2014] [Accepted: 02/13/2014] [Indexed: 01/06/2023]
Abstract
Cytidine deaminases have important roles in the regulation of nucleoside/deoxynucleoside pools for DNA and RNA synthesis. The APOBEC family of cytidine deaminases (named after the first member of the family that was described, Apolipoprotein B mRNA Editing Catalytic Subunit 1, also known as APOBEC1 or A1) is a fascinating group of mutagenic proteins that use RNA and single-stranded DNA (ssDNA) as substrates for their cytidine or deoxycytidine deaminase activities. APOBEC proteins and base-modification nucleic acid editing have been the subject of numerous publications, reviews, and speculation. These proteins play diverse roles in host cell defense, protecting cells from invading genetic material, enabling the acquired immune response to antigens and changing protein expression at the level of the genetic code in mRNA or DNA. The amazing power these proteins have for interphase cell functions relies on structural and biochemical properties that are beginning to be understood. At the same time, the substrate selectivity of each member in the family and their regulation remains to be elucidated. This review of the APOBEC family will focus on an open question in regulation, namely what role the interactions of these proteins with RNA have in editing substrate recognition or allosteric regulation of DNA mutagenic and host-defense activities.
Collapse
|
21
|
Janahi EM, McGarvey MJ. The inhibition of hepatitis B virus by APOBEC cytidine deaminases. J Viral Hepat 2013; 20:821-8. [PMID: 24304451 DOI: 10.1111/jvh.12192] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Accepted: 09/24/2013] [Indexed: 12/13/2022]
Abstract
APOBEC3 (A3) cytidine deaminases are a family of enzymes that have been shown to inhibit the replication of HIV-1 and other retroviruses as part of the innate immune responses to virus infection. They can also hyperedit HBV DNA and inhibit HBV replication. Although A3 proteins are present at low levels in normal liver, A3 gene expression is highly stimulated by both interferon-α and interferon-γ. A3 deaminases are incorporated into nascent HBV capsids where they cleave amino groups from cytidine bases converting them to uracil in newly synthesized DNA following reverse transcription of pregenomic RNA. This modified HBV DNA is susceptible to degradation, or alternatively, numerous G-to-A nucleotide mutations are incorporated into positive-strand viral DNA disrupting coding sequences. A3 proteins in which the cytidine deaminase activity has been lost can also inhibit HBV replication, suggesting that there may be more than one way in which inhibition can occur. There is also evidence that A3 proteins might play a role in the development of hepatocellular carcinoma during chronic HBV infection.
Collapse
Affiliation(s)
- E M Janahi
- Department of Biology, College of Science, University of Bahrain, Sakhir, Bahrain
| | | |
Collapse
|
22
|
Deng Y, Du Y, Zhang Q, Han X, Cao G. Human cytidine deaminases facilitate hepatitis B virus evolution and link inflammation and hepatocellular carcinoma. Cancer Lett 2013; 343:161-71. [PMID: 24120759 DOI: 10.1016/j.canlet.2013.09.041] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 09/27/2013] [Accepted: 09/27/2013] [Indexed: 12/13/2022]
Abstract
During hepatitis B virus (HBV)-induced hepatocarcinogenesis, chronic inflammation facilitates the evolution of hepatocellular carcinoma (HCC)-promoting HBV mutants. Cytidine deaminases, whose expression is stimulated by inflammatory cytokines and/or chemokines, play an important role in bridging inflammation and HCC. Through G-to-A hypermutation, cytidine deaminases inhibit HBV replication and facilitate the generation of HCC-promoting HBV mutants including C-terminal-truncated HBx. Cytidine deaminases also promote cancer-related somatic mutations including TP53 mutations. Their editing efficiency is counteracted by uracil-DNA glycosylase. Understanding the effects of cytidine deaminases in HBV-induced hepatocarcinogenesis and HCC progression will aid in developing efficient prophylactic and therapeutic strategies against HCC in HBV-infected population.
Collapse
Affiliation(s)
- Yang Deng
- Department of Epidemiology, Second Military Medical University, Shanghai, China
| | - Yan Du
- Department of Epidemiology, Second Military Medical University, Shanghai, China
| | - Qi Zhang
- Department of Epidemiology, Second Military Medical University, Shanghai, China
| | - Xue Han
- Division of Chronic Diseases, Center for Disease Control and Prevention of Yangpu District, Shanghai, China
| | - Guangwen Cao
- Department of Epidemiology, Second Military Medical University, Shanghai, China.
| |
Collapse
|
23
|
Rathore A, Carpenter MA, Demir Ö, Ikeda T, Li M, Shaban NM, Law EK, Anokhin D, Brown WL, Amaro RE, Harris RS. The local dinucleotide preference of APOBEC3G can be altered from 5'-CC to 5'-TC by a single amino acid substitution. J Mol Biol 2013; 425:4442-54. [PMID: 23938202 DOI: 10.1016/j.jmb.2013.07.040] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 07/18/2013] [Accepted: 07/20/2013] [Indexed: 10/26/2022]
Abstract
APOBEC3A and APOBEC3G are DNA cytosine deaminases with biological functions in foreign DNA and retrovirus restriction, respectively. APOBEC3A has an intrinsic preference for cytosine preceded by thymine (5'-TC) in single-stranded DNA substrates, whereas APOBEC3G prefers the target cytosine to be preceded by another cytosine (5'-CC). To determine the amino acids responsible for these strong dinucleotide preferences, we analyzed a series of chimeras in which putative DNA binding loop regions of APOBEC3G were replaced with the corresponding regions from APOBEC3A. Loop 3 replacement enhanced APOBEC3G catalytic activity but did not alter its intrinsic 5'-CC dinucleotide substrate preference. Loop 7 replacement caused APOBEC3G to become APOBEC3A-like and strongly prefer 5'-TC substrates. Simultaneous loop 3/7 replacement resulted in a hyperactive APOBEC3G variant that also preferred 5'-TC dinucleotides. Single amino acid exchanges revealed D317 as a critical determinant of dinucleotide substrate specificity. Multi-copy explicitly solvated all-atom molecular dynamics simulations suggested a model in which D317 acts as a helix-capping residue by constraining the mobility of loop 7, forming a novel binding pocket that favorably accommodates cytosine. All catalytically active APOBEC3G variants, regardless of dinucleotide preference, retained human immunodeficiency virus type 1 restriction activity. These data support a model in which the loop 7 region governs the selection of local dinucleotide substrates for deamination but is unlikely to be part of the higher level targeting mechanisms that direct these enzymes to biological substrates such as human immunodeficiency virus type 1 cDNA.
Collapse
Affiliation(s)
- Anurag Rathore
- Department of Biochemistry, Molecular Biology and Biophysics, Institute for Molecular Virology, Center for Genome Engineering, Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Vieira VC, Soares MA. The role of cytidine deaminases on innate immune responses against human viral infections. BIOMED RESEARCH INTERNATIONAL 2013; 2013:683095. [PMID: 23865062 PMCID: PMC3707226 DOI: 10.1155/2013/683095] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 05/29/2013] [Accepted: 05/31/2013] [Indexed: 02/06/2023]
Abstract
The APOBEC family of proteins comprises deaminase enzymes that edit DNA and/or RNA sequences. The APOBEC3 subgroup plays an important role on the innate immune system, acting on host defense against exogenous viruses and endogenous retroelements. The role of APOBEC3 proteins in the inhibition of viral infection was firstly described for HIV-1. However, in the past few years many studies have also shown evidence of APOBEC3 action on other viruses associated with human diseases, including HTLV, HCV, HBV, HPV, HSV-1, and EBV. APOBEC3 inhibits these viruses through a series of editing-dependent and independent mechanisms. Many viruses have evolved mechanisms to counteract APOBEC effects, and strategies that enhance APOBEC3 activity constitute a new approach for antiviral drug development. On the other hand, novel evidence that editing by APOBEC3 constitutes a source for viral genetic diversification and evolution has emerged. Furthermore, a possible role in cancer development has been shown for these host enzymes. Therefore, understanding the role of deaminases on the immune response against infectious agents, as well as their role in human disease, has become pivotal. This review summarizes the state-of-the-art knowledge of the impact of APOBEC enzymes on human viruses of distinct families and harboring disparate replication strategies.
Collapse
Affiliation(s)
- Valdimara C. Vieira
- Programa de Oncovirologia, Instituto Nacional de Câncer, Rua André Cavalcanti, No. 37–4 Andar, Bairro de Fátima, 20231-050 Rio de Janeiro, RJ, Brazil
| | - Marcelo A. Soares
- Programa de Oncovirologia, Instituto Nacional de Câncer, Rua André Cavalcanti, No. 37–4 Andar, Bairro de Fátima, 20231-050 Rio de Janeiro, RJ, Brazil
- Departamento de Genética, Universidade Federal do Rio de Janeiro, 21949-570 Rio de Janeiro, RJ, Brazil
| |
Collapse
|
25
|
Kitamura K, Wang Z, Chowdhury S, Simadu M, Koura M, Muramatsu M. Uracil DNA glycosylase counteracts APOBEC3G-induced hypermutation of hepatitis B viral genomes: excision repair of covalently closed circular DNA. PLoS Pathog 2013; 9:e1003361. [PMID: 23696735 PMCID: PMC3656096 DOI: 10.1371/journal.ppat.1003361] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 03/31/2013] [Indexed: 12/17/2022] Open
Abstract
The covalently closed circular DNA (cccDNA) of the hepatitis B virus (HBV) plays an essential role in chronic hepatitis. The cellular repair system is proposed to convert cytoplasmic nucleocapsid (NC) DNA (partially double-stranded DNA) into cccDNA in the nucleus. Recently, antiviral cytidine deaminases, AID/APOBEC proteins, were shown to generate uracil residues in the NC-DNA through deamination, resulting in cytidine-to-uracil (C-to-U) hypermutation of the viral genome. We investigated whether uracil residues in hepadnavirus DNA were excised by uracil-DNA glycosylase (UNG), a host factor for base excision repair (BER). When UNG activity was inhibited by the expression of the UNG inhibitory protein (UGI), hypermutation of NC-DNA induced by either APOBEC3G or interferon treatment was enhanced in a human hepatocyte cell line. To assess the effect of UNG on the cccDNA viral intermediate, we used the duck HBV (DHBV) replication model. Sequence analyses of DHBV DNAs showed that cccDNA accumulated G-to-A or C-to-T mutations in APOBEC3G-expressing cells, and this was extensively enhanced by UNG inhibition. The cccDNA hypermutation generated many premature stop codons in the P gene. UNG inhibition also enhanced the APOBEC3G-mediated suppression of viral replication, including reduction of NC-DNA, pre-C mRNA, and secreted viral particle-associated DNA in prolonged culture. Enhancement of APOBEC3G-mediated suppression by UNG inhibition was not observed when the catalytic site of APOBEC3G was mutated. Transfection experiments of recloned cccDNAs revealed that the combination of UNG inhibition and APOBEC3G expression reduced the replication ability of cccDNA. Taken together, these data indicate that UNG excises uracil residues from the viral genome during or after cccDNA formation in the nucleus and imply that BER pathway activities decrease the antiviral effect of APOBEC3-mediated hypermutation.
Collapse
Affiliation(s)
- Kouichi Kitamura
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Zhe Wang
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Sajeda Chowdhury
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Miyuki Simadu
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Miki Koura
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Masamichi Muramatsu
- Department of Molecular Genetics, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
- * E-mail:
| |
Collapse
|
26
|
Abstract
Organisms minimize genetic damage through complex pathways of DNA repair. Yet a gene family--the AID/APOBECs--has evolved in vertebrates with the sole purpose of producing targeted damage in DNA/RNA molecules through cytosine deamination. They likely originated from deaminases involved in A>I editing in tRNAs. AID, the archetypal AID/APOBEC, is the trigger of the somatic diversification processes of the antibody genes. Its homologs may have been associated with the immune system even before the evolution of the antibody genes. The APOBEC3s, arising from duplication of AID, are involved in the restriction of exogenous/endogenous threats such as retroviruses and mobile elements. Another family member, APOBEC1, has (re)acquired the ability to target RNA while maintaining its ability to act on DNA. The AID/APOBECs have shaped the evolution of vertebrate genomes, but their ability to mutate nucleic acids is a double-edged sword: AID is a key player in lymphoproliferative diseases by triggering mutations and chromosomal translocations in B cells, and there is increasing evidence suggesting that other AID/APOBECs could be involved in cancer development as well.
Collapse
|
27
|
Lethal mutagenesis of foot-and-mouth disease virus involves shifts in sequence space. J Virol 2011; 85:12227-40. [PMID: 21917974 DOI: 10.1128/jvi.00716-11] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lethal mutagenesis or virus transition into error catastrophe is an antiviral strategy that aims at extinguishing a virus by increasing the viral mutation rates during replication. The molecular basis of lethal mutagenesis is largely unknown. Previous studies showed that a critical substitution in the foot-and-mouth disease virus (FMDV) polymerase was sufficient to allow the virus to escape extinction through modulation of the transition types induced by the purine nucleoside analogue ribavirin. This substitution was not detected in mutant spectra of FMDV populations that had not replicated in the presence of ribavirin, using standard molecular cloning and nucleotide sequencing. Here we selectively amplify and analyze low-melting-temperature cDNA duplexes copied from FMDV genome populations passaged in the absence or presence of ribovirin Hypermutated genomes with high frequencies of A and U were present in both ribavirin -treated and untreated populations, but the major effect of ribavirin mutagenesis was to accelerate the occurrence of AU-rich mutant clouds during the early replication rounds of the virus. The standard FMDV quasispecies passaged in the absence of ribavirin included the salient transition-modulating, ribavirin resistance mutation, whose frequency increased in populations treated with ribavirin. Thus, even nonmutagenized FMDV quasispecies include a deep, mutationally biased portion of sequence space, in support of the view that the virus replicates close to the error threshold for maintenance of genetic information.
Collapse
|
28
|
Vartanian JP, Henry M, Marchio A, Suspène R, Aynaud MM, Guétard D, Cervantes-Gonzalez M, Battiston C, Mazzaferro V, Pineau P, Dejean A, Wain-Hobson S. Massive APOBEC3 editing of hepatitis B viral DNA in cirrhosis. PLoS Pathog 2010; 6:e1000928. [PMID: 20523896 PMCID: PMC2877740 DOI: 10.1371/journal.ppat.1000928] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 04/27/2010] [Indexed: 12/13/2022] Open
Abstract
DNA viruses, retroviruses and hepadnaviruses, such as hepatitis B virus (HBV), are vulnerable to genetic editing of single stranded DNA by host cell APOBEC3 (A3) cytidine deaminases. At least three A3 genes are up regulated by interferon-α in human hepatocytes while ectopic expression of activation induced deaminase (AICDA), an A3 paralog, has been noted in a variety of chronic inflammatory syndromes including hepatitis C virus infection. Yet virtually all studies of HBV editing have confined themselves to analyses of virions from culture supernatants or serum where the frequency of edited genomes is generally low (≤10−2). We decided to look at the nature and frequency of HBV editing in cirrhotic samples taken during removal of a primary hepatocellular carcinoma. Forty-one cirrhotic tissue samples (10 alcoholic, 10 HBV+, 11 HBV+HCV+ and 10 HCV+) as well as 4 normal livers were studied. Compared to normal liver, 5/7 APOBEC3 genes were significantly up regulated in the order: HCV±HBV>HBV>alcoholic cirrhosis. A3C and A3D were up regulated for all groups while the interferon inducible A3G was over expressed in virus associated cirrhosis, as was AICDA in ∼50% of these HBV/HCV samples. While AICDA can indeed edit HBV DNA ex vivo, A3G is the dominant deaminase in vivo with up to 35% of HBV genomes being edited. Despite these highly deleterious mutant spectra, a small fraction of genomes survive and contribute to loss of HBeAg antigenemia and possibly HBsAg immune escape. In conclusion, the cytokine storm associated with chronic inflammatory responses to HBV and HCV clearly up regulates a number of A3 genes with A3G clearly being a major restriction factor for HBV. Although the mutant spectrum resulting from A3 editing is highly deleterious, a very small part, notably the lightly edited genomes, might help the virus evolve and even escape immune responses. Retroviruses and hepadnaviruses such as hepatitis B virus (HBV) are vulnerable to mutation by host cell single stranded DNA cytidine deaminases. The result is hypermutated viral peppered with uracil residues. While there are potentially 11 such human enzymes, the major players belong to the 7 gene APOBEC3 cluster on chromosome 22, some of which can be activated by anti-viral interferons. We investigated the nature and frequency of HBV editing in 41 cirrhotic samples following surgical removal of primary hepatocellular carcinoma. Numerous APOBEC3 genes were activated in the decreasing order HCV±HBV>HBV>alcoholic cirrhosis. We observed that APOBEC3G was the dominant restricting factor in vivo with up to 35% of HBV edited genomes. Among the HBV mutants generated by APOBEC3 editing, we found a small fraction of lightly APOBEC3G edited genomes that can impact HBV replication in vivo and possibly immune escape.
Collapse
|