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Niu AX, Liu J, Zhu CW. Progress in research of ubiquitination modification of hepatitis B surface antigen. WORLD CHINESE JOURNAL OF DIGESTOLOGY 2024; 32:333-338. [DOI: 10.11569/wcjd.v32.i5.333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
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Chen R, Zhang H, Li L, Li J, Xie J, Weng J, Tan H, Liu Y, Guo T, Wang M. Roles of ubiquitin-specific proteases in inflammatory diseases. Front Immunol 2024; 15:1258740. [PMID: 38322269 PMCID: PMC10844489 DOI: 10.3389/fimmu.2024.1258740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 01/02/2024] [Indexed: 02/08/2024] Open
Abstract
Ubiquitin-specific proteases (USPs), as one of the deubiquitinating enzymes (DUBs) families, regulate the fate of proteins and signaling pathway transduction by removing ubiquitin chains from the target proteins. USPs are essential for the modulation of a variety of physiological processes, such as DNA repair, cell metabolism and differentiation, epigenetic modulations as well as protein stability. Recently, extensive research has demonstrated that USPs exert a significant impact on innate and adaptive immune reactions, metabolic syndromes, inflammatory disorders, and infection via post-translational modification processes. This review summarizes the important roles of the USPs in the onset and progression of inflammatory diseases, including periodontitis, pneumonia, atherosclerosis, inflammatory bowel disease, sepsis, hepatitis, diabetes, and obesity. Moreover, we highlight a comprehensive overview of the pathogenesis of USPs in these inflammatory diseases as well as post-translational modifications in the inflammatory responses and pave the way for future prospect of targeted therapies in these inflammatory diseases.
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Affiliation(s)
- Rui Chen
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- Department of Stomatology, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, Sichuan, China
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Hui Zhang
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
- College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Linke Li
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- Department of Stomatology, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Jinsheng Li
- College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Jiang Xie
- Department of Pediatrics, Chengdu Third People's Hospital, Chengdu, Sichuan, China
| | - Jie Weng
- College of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Huan Tan
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Yanjun Liu
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Tailin Guo
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Mengyuan Wang
- Center of Obesity and Metabolic Diseases, Department of General Surgery, The Third People's Hospital of Chengdu, Affiliated Hospital of Southwest Jiaotong University, Chengdu, China
- Department of Stomatology, The Third People's Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University, Chengdu, Sichuan, China
- College of Medicine, Southwest Jiaotong University, Chengdu, Sichuan, China
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Ren J, Yu P, Liu S, Li R, Niu X, Chen Y, Zhang Z, Zhou F, Zhang L. Deubiquitylating Enzymes in Cancer and Immunity. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2303807. [PMID: 37888853 PMCID: PMC10754134 DOI: 10.1002/advs.202303807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 08/30/2023] [Indexed: 10/28/2023]
Abstract
Deubiquitylating enzymes (DUBs) maintain relative homeostasis of the cellular ubiquitome by removing the post-translational modification ubiquitin moiety from substrates. Numerous DUBs have been demonstrated specificity for cleaving a certain type of ubiquitin linkage or positions within ubiquitin chains. Moreover, several DUBs perform functions through specific protein-protein interactions in a catalytically independent manner, which further expands the versatility and complexity of DUBs' functions. Dysregulation of DUBs disrupts the dynamic equilibrium of ubiquitome and causes various diseases, especially cancer and immune disorders. This review summarizes the Janus-faced roles of DUBs in cancer including proteasomal degradation, DNA repair, apoptosis, and tumor metastasis, as well as in immunity involving innate immune receptor signaling and inflammatory and autoimmune disorders. The prospects and challenges for the clinical development of DUB inhibitors are further discussed. The review provides a comprehensive understanding of the multi-faced roles of DUBs in cancer and immunity.
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Affiliation(s)
- Jiang Ren
- The Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhen518033P. R. China
| | - Peng Yu
- Zhongshan Institute for Drug DiscoveryShanghai Institute of Materia MedicaChinese Academy of SciencesZhongshanGuangdongP. R. China
| | - Sijia Liu
- International Biomed‐X Research CenterSecond Affiliated Hospital of Zhejiang University School of MedicineZhejiang UniversityHangzhouP. R. China
- Key Laboratory of Precision Diagnosis and Treatment for Hepatobiliary and Pancreatic Tumor of Zhejiang ProvinceHangzhou310058China
| | - Ran Li
- The Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhen518033P. R. China
| | - Xin Niu
- MOE Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling NetworkLife Sciences InstituteZhejiang UniversityHangzhou310058P. R. China
| | - Yan Chen
- The Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhen518033P. R. China
| | - Zhenyu Zhang
- Department of NeurosurgeryThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan450003P. R. China
| | - Fangfang Zhou
- Institutes of Biology and Medical ScienceSoochow UniversitySuzhou215123P. R. China
| | - Long Zhang
- The Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhen518033P. R. China
- International Biomed‐X Research CenterSecond Affiliated Hospital of Zhejiang University School of MedicineZhejiang UniversityHangzhouP. R. China
- MOE Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling NetworkLife Sciences InstituteZhejiang UniversityHangzhou310058P. R. China
- Cancer CenterZhejiang UniversityHangzhouZhejiang310058P. R. China
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Pi Y, Li Y, Yan Q, Luo H, Zhou P, Chang W, Gong D, Hu Y, Wang K, Tang N, Huang A, Chen Y. SPOP inhibits HBV transcription and replication by ubiquitination and degradation of HNF1α. J Med Virol 2023; 95:e29254. [PMID: 38018242 DOI: 10.1002/jmv.29254] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/20/2023] [Accepted: 11/11/2023] [Indexed: 11/30/2023]
Abstract
Hepatitis B virus (HBV) infection remains a significant public health burden worldwide. The persistence of covalently closed circular DNA (cccDNA) within the nucleus of infected hepatocytes is responsible for the failure of antiviral treatments. The ubiquitin proteasome system (UPS) has emerged as a promising antiviral target, as it can regulate HBV replication by promoting critical protein degradation in steps of viral life cycle. Speckle-type POZ protein (SPOP) is a critical adaptor for Cul3-RBX1 E3 ubiquitin ligase complex, but the effect of SPOP on HBV replication is less known. Here, we identified SPOP as a novel host antiviral factor against HBV infection. SPOP overexpression significantly inhibited the transcriptional activity of HBV cccDNA without affecting cccDNA level in HBV-infected HepG2-NTCP and primary human hepatocyte cells. Mechanism studies showed that SPOP interacted with hepatocyte nuclear factor 1α (HNF1α), and induced HNF1α degradation through host UPS pathway. Moreover, the antiviral role of SPOP was also confirmed in vivo. Together, our findings reveal that SPOP is a novel host factor which inhibits HBV transcription and replication by ubiquitination and degradation of HNF1α, providing a potential therapeutic strategy for the treatment of HBV infection.
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Affiliation(s)
- Yubo Pi
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Yang Li
- Chongqing Big Data Research Institute of Peking University, Chongqing, China
| | - Qi Yan
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Huimin Luo
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Peng Zhou
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Wenyi Chang
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Deao Gong
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Yuan Hu
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Kai Wang
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Ni Tang
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Ailong Huang
- Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Diseases, Ministry of Education, The Second Affiliated Hospital of Chongqing Medical University, Institute for Viral Hepatitis, Chongqing, China
| | - Yanmeng Chen
- Key Laboratory of Laboratory Medical Diagnostics, Department of Laboratory Medicine, Ministry of Education, Chongqing Medical University, Chongqing, China
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Kar A, Samanta A, Mukherjee S, Barik S, Biswas A. The HBV web: An insight into molecular interactomes between the hepatitis B virus and its host en route to hepatocellular carcinoma. J Med Virol 2023; 95:e28436. [PMID: 36573429 DOI: 10.1002/jmv.28436] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 11/26/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022]
Abstract
Hepatitis B virus (HBV) is a major aetiology associated with the development and progression of hepatocellular carcinoma (HCC), the most common primary liver malignancy. Over the past few decades, direct and indirect mechanisms have been identified in the pathogenesis of HBV-associated HCC which include altered signaling pathways, genome integration, mutation-induced genomic instability, chromosomal deletions and rearrangements. Intertwining of the HBV counterparts with the host cellular factors, though well established, needs to be systemized to understand the dynamics of host-HBV crosstalk and its consequences on HCC progression. Existence of a vast array of protein-protein and protein-nucleic acid interaction databases has led to the uncoiling of the compendia of genes/gene products associated with these interactions. This review covers the existing knowledge about the HBV-host interplay and brings it down under one canopy emphasizing on the HBV-host interactomics; and thereby highlights new strategies for therapeutic advancements against HBV-induced HCC.
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Affiliation(s)
- Arpita Kar
- Department of Signal Transduction and Biogenic Amines, Chittaranjan National Cancer Institute, Kolkata, West Bengal, India
| | - Abhisekh Samanta
- Department of Signal Transduction and Biogenic Amines, Chittaranjan National Cancer Institute, Kolkata, West Bengal, India
| | - Soumyadeep Mukherjee
- Department of In Vitro Carcinogenesis and Cellular Chemotherapy, Chittaranjan National Cancer Institute, Kolkata, West Bengal, India
| | - Subhasis Barik
- Department of In Vitro Carcinogenesis and Cellular Chemotherapy, Chittaranjan National Cancer Institute, Kolkata, West Bengal, India
| | - Avik Biswas
- Department of Signal Transduction and Biogenic Amines, Chittaranjan National Cancer Institute, Kolkata, West Bengal, India
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Zhang Y, Li L, Cheng ST, Qin YP, He X, Li F, Wu DQ, Ren F, Yu HB, Liu J, Chen J, Ren JH, Zhang ZZ. Rapamycin inhibits hepatitis B virus covalently closed circular DNA transcription by enhancing the ubiquitination of HBx. Front Microbiol 2022; 13:850087. [PMID: 36033851 PMCID: PMC9403416 DOI: 10.3389/fmicb.2022.850087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Hepatitis B virus (HBV) infection is still a serious public health problem worldwide. Antiviral therapies such as interferon and nucleos(t)ide analogs efficiently control HBV replication, but they cannot eradicate chronic hepatitis B (CHB) because of their incapacity to eliminate endocellular covalently closed circular DNA (cccDNA). Thus, there is a necessity to develop new strategies for targeting cccDNA. As cccDNA is difficult to clear, transcriptional silencing of cccDNA is a possible effective strategy. HBx plays a vitally important role in maintaining the transcriptional activity of cccDNA and it could be a target for blocking the transcription of cccDNA. To screen new drugs that may contribute to antiviral therapy, the ability of 2,000 small-molecule compounds to inhibit HBx was examined by the HiBiT lytic detection system. We found that the macrolide compound rapamycin, which is clinically used to prevent acute rejection after organ transplantation, could significantly reduce HBx protein expression. Mechanistic studies demonstrated that rapamycin decreased the stability of the HBx protein by promoting its degradation via the ubiquitin-proteasome system. Moreover, rapamycin inhibited HBV RNA, HBV DNA, and cccDNA transcription levels in HBV-infected cells. In addition, HBx deficiency abrogated the inhibition of cccDNA transcription induced by rapamycin. Similar results were also confirmed in a recombinant cccDNA mouse model. In summary, we report a new small-molecule, rapamycin, which targets HBx to block HBV cccDNA transcription and inhibit HBV replication. This approach can identify new strategies to cure CHB.
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Affiliation(s)
- Yuan Zhang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
- Department of Infectious Disease, Children’s Hospital of Chongqing Medical University, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- Chongqing Key Laboratory of Child Infection and Immunity, Chongqing, China
| | - Liang Li
- Department of Gastroenterology, Chongqing University Three Gorges Hospital, Chongqing, China
| | - Sheng-Tao Cheng
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yi-Ping Qin
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Xin He
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Fan Li
- Department of Endocrine and Breast Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Dai-Qing Wu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Fang Ren
- Chongqing Key Laboratory of Sichuan-Chongqing Co-construction for Diagnosis and Treatment of Infectious Diseases Integrated Traditional Chinese and Western Medicine, Chongqing, China
- Department of Laboratory Medicine, Chongqing Hospital of Traditional Chinese Medicine, Chongqing, China
| | - Hai-Bo Yu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Jing Liu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Juan Chen
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Ji-Hua Ren
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
- Ji-Hua Ren,
| | - Zhen-Zhen Zhang
- Department of Infectious Disease, Children’s Hospital of Chongqing Medical University, Chongqing, China
- National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China
- Chongqing Key Laboratory of Child Infection and Immunity, Chongqing, China
- *Correspondence: Zhen-Zhen Zhang,
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Hepatitis B Virus X Protein Is Stabilized by the Deubiquitinating Enzyme VCPIP1 in a Ubiquitin-Independent Manner by Recruiting the 26S Proteasome Subunit PSMC3. J Virol 2022; 96:e0061122. [PMID: 35695579 PMCID: PMC9278118 DOI: 10.1128/jvi.00611-22] [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] [Indexed: 12/09/2022] Open
Abstract
Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide, and the viral X protein (HBx) is an etiological factor in HCC development. HBx is a high-turnover protein, but knowledge of the role of deubiquitinating enzymes (DUBs) in maintaining HBx homeostasis is very limited. We used a 74-DUB library-based yeast two-hybrid assay and determined that a novel DUB, valosin-containing protein-interacting protein 1 (VCPIP1), interacted with HBx. VCPIP1 and its C-terminal amino acids 863 to 1221 upregulated the HBx protein expression, with or without HBV infection. Mechanistically, VCPIP1 stabilized HBx protein through a ubiquitin-independent pathway, which was validated by the HBx ubiquitination site mutant plasmid. Coimmunoprecipitation assays demonstrated the potency of VCPIP1 in recruiting 26S proteasome regulatory subunit 6A (PSMC3) and forming a ternary complex with HBx through mutual interaction. In vitro, purified His-tagged PSMC3 protein rescued HBx degradation induced by the 20S proteasome, and in vivo VCPIP1 synergized the mechanism. Functionally, HBx specifically binding to VCPIP1 significantly enhanced the transcriptional transactivation of HBx by activating NF-κB, AP-1, and SP-1 and inhibited hepatoma cell clonogenicity in Huh7 and HepG2 cells. Moreover, we further demonstrated that overexpression of VCPIP1 significantly affected the HBV covalently closed circular DNA (cccDNA) transcription in HBV-infected HepG2-NTCP cells. Altogether, our results indicate a novel mechanism by which VCPIP1 recruits PSMC3 to bind with HBx, stabilizing it in a ubiquitin-independent manner, which might be critical for developing DUB inhibitors in the future. IMPORTANCE HBx is a multifunctional viral oncoprotein that plays an essential role in the viral life cycle and hepatocarcinogenesis. HBx degradation occurs through the ubiquitin-proteasome system (UPS). However, whether novel compartments of the DUBs in the UPS also act in regulating HBx stability is not fully understood. Here, for the first time, we defined VCPIP1 as a novel DUB for preventing HBx degradation by the 20S proteasome in a ubiquitin-independent manner. PSMC3, encoding the 26S proteasome regulatory subunit, directly stabilized HBx through physical binding instead of a common approach in protein degradation, serving as the key downstream effector of VCPIP1 on HBx. Therefore, the ternary binding pattern between VCPIP1, HBx, and PSMC3 is initiated for the first time, which eventually promotes HBx stability and its functions. Our findings provide novel insights into host-virus cross talk by targeting DUBs in the UPS.
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Li YC, Cai SW, Shu YB, Chen MW, Shi Z. USP15 in Cancer and Other Diseases: From Diverse Functionsto Therapeutic Targets. Biomedicines 2022; 10:biomedicines10020474. [PMID: 35203682 PMCID: PMC8962386 DOI: 10.3390/biomedicines10020474] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/09/2022] [Accepted: 02/13/2022] [Indexed: 12/10/2022] Open
Abstract
The process of protein ubiquitination and deubiquitination plays an important role in maintaining protein stability and regulating signal pathways, and protein homeostasis perturbations may induce a variety of diseases. The deubiquitination process removes ubiquitin molecules from the protein, which requires the participation of deubiquitinating enzymes (DUBs). Ubiquitin-specific protease 15 (USP15) is a DUB that participates in many biological cell processes and regulates tumorigenesis. A dislocation catalytic triplet was observed in the USP15 structure, a conformation not observed in other USPs, except USP7, which makes USP15 appear to be unique. USP15 has been reported to be involved in the regulation of various cancers and diseases, and the reported substrate functions of USP15 are conflicting, suggesting that USP15 may act as both an oncogene and a tumor suppressor in different contexts. The importance and complexity of USP15 in the pathological processes remains unclear. Therefore, we reviewed the diverse biological functions of USP15 in cancers and other diseases, suggesting the potential of USP15 as an attractive therapeutic target.
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Affiliation(s)
- Yan-Chi Li
- Department of Cell Biology & Institute of Biomedicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Center of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; (Y.-C.L.); (Y.-B.S.)
| | - Song-Wang Cai
- Department of Thoracic Surgery, The First Affiliated Hospital of Jinan University, Guangzhou 510632, China;
| | - Yu-Bin Shu
- Department of Cell Biology & Institute of Biomedicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Center of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; (Y.-C.L.); (Y.-B.S.)
| | - Mei-Wan Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 519000, China;
| | - Zhi Shi
- Department of Cell Biology & Institute of Biomedicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Center of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; (Y.-C.L.); (Y.-B.S.)
- Correspondence: ; Tel.: +86-20-852-245-25; Fax: +86-20-852-259-77
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Van Damme E, Vanhove J, Severyn B, Verschueren L, Pauwels F. The Hepatitis B Virus Interactome: A Comprehensive Overview. Front Microbiol 2021; 12:724877. [PMID: 34603251 PMCID: PMC8482013 DOI: 10.3389/fmicb.2021.724877] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/17/2021] [Indexed: 12/19/2022] Open
Abstract
Despite the availability of a prophylactic vaccine, chronic hepatitis B (CHB) caused by the hepatitis B virus (HBV) is a major health problem affecting an estimated 292 million people globally. Current therapeutic goals are to achieve functional cure characterized by HBsAg seroclearance and the absence of HBV-DNA after treatment cessation. However, at present, functional cure is thought to be complicated due to the presence of covalently closed circular DNA (cccDNA) and integrated HBV-DNA. Even if the episomal cccDNA is silenced or eliminated, it remains unclear how important the high level of HBsAg that is expressed from integrated HBV DNA is for the pathology. To identify therapies that could bring about high rates of functional cure, in-depth knowledge of the virus' biology is imperative to pinpoint mechanisms for novel therapeutic targets. The viral proteins and the episomal cccDNA are considered integral for the control and maintenance of the HBV life cycle and through direct interaction with the host proteome they help create the most optimal environment for the virus whilst avoiding immune detection. New HBV-host protein interactions are continuously being identified. Unfortunately, a compendium of the most recent information is lacking and an interactome is unavailable. This article provides a comprehensive review of the virus-host relationship from viral entry to release, as well as an interactome of cccDNA, HBc, and HBx.
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Affiliation(s)
- Ellen Van Damme
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Jolien Vanhove
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium.,Early Discovery Biology, Charles River Laboratories, Beerse, Belgium
| | - Bryan Severyn
- Janssen Research & Development, Janssen Pharmaceutical Companies, Springhouse, PA, United States
| | - Lore Verschueren
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Frederik Pauwels
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
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Singh P, Kairuz D, Arbuthnot P, Bloom K. Silencing hepatitis B virus covalently closed circular DNA: The potential of an epigenetic therapy approach. World J Gastroenterol 2021; 27:3182-3207. [PMID: 34163105 PMCID: PMC8218364 DOI: 10.3748/wjg.v27.i23.3182] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/23/2021] [Accepted: 05/07/2021] [Indexed: 02/06/2023] Open
Abstract
Global prophylactic vaccination programmes have helped to curb new hepatitis B virus (HBV) infections. However, it is estimated that nearly 300 million people are chronically infected and have a high risk of developing hepatocellular carcinoma. As such, HBV remains a serious health priority and the development of novel curative therapeutics is urgently needed. Chronic HBV infection has been attributed to the persistence of the covalently closed circular DNA (cccDNA) which establishes itself as a minichromosome in the nucleus of hepatocytes. As the viral transcription intermediate, the cccDNA is responsible for producing new virions and perpetuating infection. HBV is dependent on various host factors for cccDNA formation and the minichromosome is amenable to epigenetic modifications. Two HBV proteins, X (HBx) and core (HBc) promote viral replication by modulating the cccDNA epigenome and regulating host cell responses. This includes viral and host gene expression, chromatin remodeling, DNA methylation, the antiviral immune response, apoptosis, and ubiquitination. Elimination of the cccDNA minichromosome would result in a sterilizing cure; however, this may be difficult to achieve. Epigenetic therapies could permanently silence the cccDNA minichromosome and promote a functional cure. This review explores the cccDNA epigenome, how host and viral factors influence transcription, and the recent epigenetic therapies and epigenome engineering approaches that have been described.
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Affiliation(s)
- Prashika Singh
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Dylan Kairuz
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
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Proulx J, Borgmann K, Park IW. Role of Virally-Encoded Deubiquitinating Enzymes in Regulation of the Virus Life Cycle. Int J Mol Sci 2021; 22:ijms22094438. [PMID: 33922750 PMCID: PMC8123002 DOI: 10.3390/ijms22094438] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 01/21/2023] Open
Abstract
The ubiquitin (Ub) proteasome system (UPS) plays a pivotal role in regulation of numerous cellular processes, including innate and adaptive immune responses that are essential for restriction of the virus life cycle in the infected cells. Deubiquitination by the deubiquitinating enzyme, deubiquitinase (DUB), is a reversible molecular process to remove Ub or Ub chains from the target proteins. Deubiquitination is an integral strategy within the UPS in regulating survival and proliferation of the infecting virus and the virus-invaded cells. Many viruses in the infected cells are reported to encode viral DUB, and these vial DUBs actively disrupt cellular Ub-dependent processes to suppress host antiviral immune response, enhancing virus replication and thus proliferation. This review surveys the types of DUBs encoded by different viruses and their molecular processes for how the infecting viruses take advantage of the DUB system to evade the host immune response and expedite their replication.
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Affiliation(s)
- Jessica Proulx
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (J.P.); (K.B.)
| | - Kathleen Borgmann
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (J.P.); (K.B.)
| | - In-Woo Park
- Department of Microbiology, Immunology and Genetics, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
- Correspondence: ; Tel.: +1-(817)-735-5115; Fax: +1-(817)-735-2610
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12
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Yuan S, Tanzeel Y, Tian X, Zheng D, Wajeeha N, Xu J, Ke Y, Zhang Z, Peng X, Lu L, Sun G, Guo D, Wang M. Global analysis of HBV-mediated host proteome and ubiquitylome change in HepG2.2.15 human hepatoblastoma cell line. Cell Biosci 2021; 11:75. [PMID: 33865438 PMCID: PMC8052555 DOI: 10.1186/s13578-021-00588-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/08/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) infection remains a major health issue worldwide and the leading cause of cirrhosis and hepatocellular carcinoma (HCC). It has been reported previously that HBV invasion can extensively alter transcriptome, the proteome of exosomes and host cell lipid rafts. The impact of HBV on host proteins through regulating their global post-translational modifications (PTMs), however, is not well studied. Viruses have been reported to exploit cellular processes by enhancing or inhibiting the ubiquitination of specific substrates. Nevertheless, host cell physiology in terms of global proteome and ubiquitylome has not been addressed yet. Here by using HBV-integrated HepG2.2.15 model cell line we first report that HBV significantly modify the host global ubiquitylome. As currently the most widely used HBV cell culture model, HepG2.2.15 can be cultivated for multiple generations for protein labeling, and can replicate HBV, express HBV proteins and secrete complete HBV Dane particles, which makes it a suitable cell line for ubiquitylome analysis to study HBV replication, hepatocyte immune response and HBV-related HCC progression. Our previous experimental results showed that the total ubiquitination level of HepG2.2.15 cell line was significantly higher than that of the corresponding parental HepG2 cell line. By performing a Ubiscan quantification analysis based on stable isotope labeling of amino acids in cell culture (SILAC) of HepG2.2.15 and HepG2 cell lines, we identified a total of 7188 proteins and the protein levels of nearly 19% of them were changed over 2-folds. We further identified 3798 ubiquitinated Lys sites in 1476 host proteins with altered ubiquitination in response to HBV. Our results also showed that the global proteome and ubiquitylome were negatively correlated, indicating that ubiquitination might be involved in the degradation of host proteins upon HBV integration. We first demonstrated the ubiquitination change of VAMP3, VAMP8, DNAJB6, RAB8A, LYN, VDAC2, OTULIN, SLC1A4, SLC1A5, HGS and TOLLIP. In addition, we described 5 novel host factors SLC1A4, SLC1A5, EIF4A1, TOLLIP and BRCC36 that efficiently reduced the amounts of secreted HBsAg and HBeAg. Overall, the HBV-mediated host proteome and ubiquitylome change we reported will provide a valuable resource for further investigation of HBV pathogenesis and host-virus interaction networks.
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Affiliation(s)
- Sen Yuan
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Yousaf Tanzeel
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Xuezhang Tian
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Dandan Zheng
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Naz Wajeeha
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Jiaqi Xu
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Yujia Ke
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Zuopeng Zhang
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China
| | - Xiaojun Peng
- Jingjie PTM BioLab (Hangzhou) Co. Ltd., Hangzhou, People's Republic of China
| | - Long Lu
- School of Information Management, Wuhan University, Wuhan, People's Republic of China
| | - Guihong Sun
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China. .,Hubei Provincial Key Laboratory of Allergy and Immunology, Wuhan, People's Republic of China.
| | - Deyin Guo
- School of Medicine, Sun Yat-Sen University, Shenzhen, People's Republic of China.
| | - Min Wang
- School of Basic Medical Sciences, Wuhan University, Wuhan, People's Republic of China.
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Yao J, Li C, Shi L, Lu Y, Liu X. Zebrafish ubiquitin-specific peptidase 5 (USP5) activates interferon resistance to the virus by increase the expression of RIG-I. Gene 2020; 751:144761. [DOI: 10.1016/j.gene.2020.144761] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/02/2020] [Accepted: 05/08/2020] [Indexed: 12/15/2022]
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Chromatin remodelling factor BAF155 protects hepatitis B virus X protein (HBx) from ubiquitin-independent proteasomal degradation. Emerg Microbes Infect 2020; 8:1393-1405. [PMID: 31533543 PMCID: PMC6758689 DOI: 10.1080/22221751.2019.1666661] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
HBx is a short-lived protein whose rapid turnover is mainly regulated by ubiquitin-dependent proteasomal degradation pathways. Our prior work identified BAF155 to be one of the HBx binding partners. Since BAF155 has been shown to stabilize other members of the SWI/SNF chromatin remodelling complex by attenuating their proteasomal degradation, we proposed that BAF155 might also contribute to stabilizing HBx protein in a proteasome-dependent manner. Here we report that BAF155 protected hepatitis B virus X protein (HBx) from ubiquitin-independent proteasomal degradation by competing with the 20S proteasome subunit PSMA7 to bind to HBx. BAF155 was found to directly interact with HBx via binding of its SANT domain to the HBx region between amino acid residues 81 and 120. Expression of either full-length BAF155 or SANT domain increased HBx protein levels whereas siRNA-mediated knockdown of endogenous BAF155 reduced HBx protein levels. Increased HBx stability and steady-state level by BAF155 were attributable to inhibition of ubiquitin-independent and PSMA7-mediated protein degradation. Consequently, overexpression of BAF155 enhanced the transcriptional transactivation function of HBx, activated protooncogene expression and inhibited hepatoma cell clonogenicity. These results suggest that BAF155 plays important roles in ubiquitin-independent degradation of HBx, which may be related to the pathogenesis and carcinogenesis of HBV-associated HCC.
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15
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Prescott NA, Bram Y, Schwartz RE, David Y. Targeting Hepatitis B Virus Covalently Closed Circular DNA and Hepatitis B Virus X Protein: Recent Advances and New Approaches. ACS Infect Dis 2019; 5:1657-1667. [PMID: 31525994 DOI: 10.1021/acsinfecdis.9b00249] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Chronic Hepatitis B virus (HBV) infection remains a worldwide concern and public health problem. Two key aspects of the HBV life cycle are essential for viral replication and thus the development of chronic infections: the establishment of the viral minichromosome, covalently closed circular (ccc) DNA, within the nucleus of infected hepatocytes and the expression of the regulatory Hepatitis B virus X protein (HBx). Interestingly, nuclear HBx redirects host epigenetic machinery to activate cccDNA transcription. In this Perspective, we provide an overview of recent advances in understanding the regulation of cccDNA and the mechanistic and functional roles of HBx. We also describe the progress toward targeting both cccDNA and HBx for therapeutic purposes. Finally, we outline standing questions in the field and propose complementary chemical biology approaches to address them.
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Affiliation(s)
- Nicholas A. Prescott
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
| | - Yaron Bram
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10065, United States
| | - Robert E. Schwartz
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10065, United States
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10065, United States
| | - Yael David
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, United States
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10065, United States
- Department of Pharmacology, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10065, United States
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Kong F, You H, Kong D, Zheng K, Tang R. The interaction of hepatitis B virus with the ubiquitin proteasome system in viral replication and associated pathogenesis. Virol J 2019; 16:73. [PMID: 31146743 PMCID: PMC6543661 DOI: 10.1186/s12985-019-1183-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/20/2019] [Indexed: 12/21/2022] Open
Abstract
Background The ubiquitin proteasome system (UPS) regulates the expression levels of cellular proteins by ubiquitination of protein substrates followed by their degradation via the proteasome. As a highly conserved cellular degradation mechanism, the UPS affects a variety of biological processes and participates in viral propagation. Main body During hepatitis B virus (HBV) infection, the UPS is shown to act as a double-edged sword in viral pathogenesis. On the one hand, the UPS acts as a host defense mechanism to selectively recognize HBV proteins as well as special cellular proteins that favor the viral life cycle and induces their ubiquitin-dependent proteasomal degradation to limit HBV infection. On the other hand, the HBV has evolved to subvert the UPS function for its own advantage. Moreover, in the infected hepatocytes, certain cellular proteins that are dependent on the UPS are involved in abnormal biological processes which are mediated by HBV. Conclusion The molecular interaction of HBV with the UPS to modulate viral propagation and pathogenesis is summarized in the review. Considering the important role of the UPS in HBV infection, a better understanding of the HBV-UPS interaction could provide novel insight into the mechanisms that are involved in viral replication and pathogenesis and help to develop potential treatment strategies targeting the UPS.
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Affiliation(s)
- Fanyun Kong
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China
| | - Hongjuan You
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China
| | - Delong Kong
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China
| | - Kuiyang Zheng
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China.,National Demonstration Center for Experimental Basic Medical Sciences Education, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China
| | - Renxian Tang
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China. .,National Demonstration Center for Experimental Basic Medical Sciences Education, Xuzhou Medical University, Xuzhou, 221004, Jiangsu, China.
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USP15 Participates in Hepatitis C Virus Propagation through Regulation of Viral RNA Translation and Lipid Droplet Formation. J Virol 2019; 93:JVI.01708-18. [PMID: 30626683 DOI: 10.1128/jvi.01708-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 12/23/2018] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) utilizes cellular factors for efficient propagation. Ubiquitin is covalently conjugated to the substrate to alter its stability or to modulate signal transduction. In this study, we examined the importance of ubiquitination for HCV propagation. We found that inhibition of deubiquitinating enzymes (DUBs) or overexpression of nonspecific DUBs impaired HCV replication, suggesting that ubiquitination regulates HCV replication. To identify specific DUBs involved in HCV propagation, we set up RNA interference (RNAi) screening against DUBs and successfully identified ubiquitin-specific protease 15 (USP15) as a novel host factor for HCV propagation. Our studies showed that USP15 is involved in translation of HCV RNA and production of infectious HCV particles. In addition, deficiency of USP15 in human hepatic cell lines (Huh7 and Hep3B/miR-122 cells) but not in a nonhepatic cell line (293T cells) impaired HCV propagation, suggesting that USP15 participates in HCV propagation through the regulation of hepatocyte-specific functions. Moreover, we showed that loss of USP15 had no effect on innate immune responses in vitro and in vivo We also found that USP15-deficient Huh7 cells showed reductions in the amounts of lipid droplets (LDs), and the addition of palmitic acids restored the production of infectious HCV particles. Taken together, these data suggest that USP15 participates in HCV propagation by regulating the translation of HCV RNA and the formation of LDs.IMPORTANCE Although ubiquitination has been shown to play important roles in the HCV life cycle, the roles of deubiquitinating enzymes (DUBs), which cleave ubiquitin chains from their substrates, in HCV propagation have not been investigated. Here, we identified USP15 as a DUB regulating HCV propagation. USP15 showed no interaction with viral proteins and no participation in innate immune responses. Deficiency of USP15 in Huh7 cells resulted in suppression of the translation of HCV RNA and reduction in the amounts of lipid droplets, and the addition of fatty acids partially restored the production of infectious HCV particles. These data suggest that USP15 participates in HCV propagation in hepatic cells through the regulation of viral RNA translation and lipid metabolism.
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