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Guo NJ, Wang B, Zhang Y, Kang HQ, Nie HQ, Feng MK, Zhang XY, Zhao LJ, Wang N, Liu HM, Zheng YC, Li W, Gao Y. USP7 as an emerging therapeutic target: A key regulator of protein homeostasis. Int J Biol Macromol 2024; 263:130309. [PMID: 38382779 DOI: 10.1016/j.ijbiomac.2024.130309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/19/2024] [Accepted: 02/18/2024] [Indexed: 02/23/2024]
Abstract
Maintaining protein balance within a cell is essential for proper cellular function, and disruptions in the ubiquitin-proteasome pathway, which is responsible for degrading and recycling unnecessary or damaged proteins, can lead to various diseases. Deubiquitinating enzymes play a vital role in regulating protein homeostasis by removing ubiquitin chains from substrate proteins, thereby controlling important cellular processes, such as apoptosis and DNA repair. Among these enzymes, ubiquitin-specific protease 7 (USP7) is of particular interest. USP7 is a cysteine protease consisting of a TRAF region, catalytic region, and C-terminal ubiquitin-like (UBL) region, and it interacts with tumor suppressors, transcription factors, and other key proteins involved in cell cycle regulation and epigenetic control. Moreover, USP7 has been implicated in the pathogenesis and progression of various diseases, including cancer, inflammation, neurodegenerative conditions, and viral infections. Overall, characterizing the functions of USP7 is crucial for understanding the pathophysiology of diverse diseases and devising innovative therapeutic strategies. This article reviews the structure and function of USP7 and its complexes, its association with diseases, and its known inhibitors and thus represents a valuable resource for advancing USP7 inhibitor development and promoting potential future treatment options for a wide range of diseases.
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Affiliation(s)
- Ning-Jie Guo
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Bo Wang
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Yu Zhang
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Hui-Qin Kang
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Hai-Qian Nie
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Meng-Kai Feng
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Xi-Ya Zhang
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Li-Juan Zhao
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Ning Wang
- The School of Chinese Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Hong-Min Liu
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Yi-Chao Zheng
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China.
| | - Wen Li
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China.
| | - Ya Gao
- State Key Laboratory of Esophageal Cancer Prevention & Treatment, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Key Laboratory of Henan Province for Drug Quality and Evaluation, Henan Province, Institute of Drug Discovery and Development; School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China.
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2
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Park HB, Baek KH. Current and future directions of USP7 interactome in cancer study. Biochim Biophys Acta Rev Cancer 2023; 1878:188992. [PMID: 37775071 DOI: 10.1016/j.bbcan.2023.188992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/14/2023] [Accepted: 09/23/2023] [Indexed: 10/01/2023]
Abstract
The ubiquitin-proteasome system (UPS) is an essential protein quality controller for regulating protein homeostasis and autophagy. Ubiquitination is a protein modification process that involves the binding of one or more ubiquitins to substrates through a series of enzymatic processes. These include ubiquitin-activating enzymes (E1), ubiquitin-conjugating enzymes (E2), and ubiquitin ligases (E3). Conversely, deubiquitination is a reverse process that removes ubiquitin from substrates via deubiquitinating enzymes (DUBs). Dysregulation of ubiquitination-related enzymes can lead to various human diseases, including cancer, through the modulation of protein ubiquitination. The most structurally and functionally studied DUB is the ubiquitin-specific protease 7 (USP7). Both the TRAF and UBL domains of USP7 are known to bind to the [P/A/E]-X-X-S or K-X-X-X-K motif of substrates. USP7 has been shown to be involved in cancer pathogenesis by binding with numerous substrates. Recently, a novel substrate of USP7 was discovered through a systemic analysis of its binding motif. This review summarizes the currently discovered substrates and cellular functions of USP7 in cancer and suggests putative substrates of USP7 through a comprehensive systemic analysis.
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Affiliation(s)
- Hong-Beom Park
- Department of Convergence, CHA University, Gyeonggi-Do 13488, Republic of Korea
| | - Kwang-Hyun Baek
- Department of Convergence, CHA University, Gyeonggi-Do 13488, Republic of Korea; International Ubiquitin Center(,) CHA University, Gyeonggi-Do 13488, Republic of Korea.
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3
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Chi L, Wang H, Yu F, Gao C, Dai H, Si X, Liu L, Wang Z, Zheng J, Ke Y, Liu H, Zhang Q. Recent Progress of Ubiquitin-Specific-Processing Protease 7 Inhibitors. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2023. [DOI: 10.1134/s1068162023020073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Kim JS, Kim HK, Cho E, Mun SJ, Jang S, Jang J, Yang CS. PE_PGRS38 Interaction With HAUSP Downregulates Antimycobacterial Host Defense via TRAF6. Front Immunol 2022; 13:862628. [PMID: 35572598 PMCID: PMC9095961 DOI: 10.3389/fimmu.2022.862628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 04/06/2022] [Indexed: 12/04/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) is the causative pathogen of tuberculosis (TB), which manipulates the host immunity to ensure survival and colonization in the host. Mtb possess a unique family of proteins, named PE_PGRS, associated with Mtb pathogenesis. Thus, elucidation of the functions of PE_PGRS proteins is necessary to understand TB pathogenesis. Here, we investigated the role of PE_PGRS38 binding to herpesvirus-associated ubiquitin-specific protease (HAUSP, USP7) in regulating the activity of various substrate proteins by modulating their state of ubiquitination. We constructed the recombinant PE_PGRS38 expressed in M. smegmatis (Ms_PE_PGRS38) to investigate the role of PE_PGRS38. We found that Ms_PE_PGRS38 regulated the cytokine levels in murine bone marrow-derived macrophages by inhibiting the deubiquitination of tumor necrosis factor receptor-associated factor (TRAF) 6 by HAUSP. Furthermore, the PE domain in PE_PGRS38 was identified as essential for mediating TRAF6 deubiquitination. Ms_PE_PGRS38 increased the intracellular burden of bacteria by manipulating cytokine levels in vitro and in vivo. Overall, we revealed that the interplay between HAUSP and PE_PGRS38 regulated the inflammatory response to increase the survival of mycobacteria.
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Affiliation(s)
- Jae-Sung Kim
- Department of Bionano Technology, Hanyang University, Seoul, South Korea.,Institute of Natural Science & Technology, Hanyang University, Ansan, South Korea
| | - Hyo Keun Kim
- Department of Molecular and Life Science, Hanyang University, Ansan, South Korea.,Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, South Korea
| | - Euni Cho
- Department of Bionano Technology, Hanyang University, Seoul, South Korea.,Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, South Korea
| | - Seok-Jun Mun
- Department of Bionano Technology, Hanyang University, Seoul, South Korea.,Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, South Korea
| | - Sein Jang
- Department of Molecular and Life Science, Hanyang University, Ansan, South Korea.,Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, South Korea
| | - Jichan Jang
- Molecular Mechanisms of Antibiotics, Division of Life Science, Research Institute of Life Science, Department of Bio & Medical Big Data (Brain Korea 21 Four Program), Gyeongsang National University, Jinju, South Korea
| | - Chul-Su Yang
- Department of Molecular and Life Science, Hanyang University, Ansan, South Korea.,Center for Bionano Intelligence Education and Research, Hanyang University, Ansan, South Korea
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Zhang Q, Jia Q, Gao W, Zhang W. The Role of Deubiquitinases in Virus Replication and Host Innate Immune Response. Front Microbiol 2022; 13:839624. [PMID: 35283827 PMCID: PMC8908266 DOI: 10.3389/fmicb.2022.839624] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 01/12/2022] [Indexed: 11/13/2022] Open
Abstract
As a critical post-translational modification, ubiquitination is known to affect almost all the cellular processes including immunity, signaling pathways, cell death, cancer development, and viral infection by controlling protein stability. Deubiquitinases (DUBs) cleave ubiquitin from proteins and reverse the process of ubiquitination. Thus, DUBs play an important role in the deubiquitination process and serve as therapeutic targets for various diseases. DUBs are found in eukaryotes, bacteria, and viruses and influence various biological processes. Here, we summarize recent findings on the function of DUBs in modulating viral infection, the mechanism by which viral DUBs regulate host innate immune response, and highlight those DUBs that have recently been discovered as antiviral therapeutic targets.
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Affiliation(s)
- Qinglin Zhang
- College of Life Sciences of Jilin University, Changchun, China
| | - Qizhen Jia
- College of Life Sciences of Jilin University, Changchun, China
| | - Wenying Gao
- Center for Pathogen Biology and Infectious Diseases, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
| | - Wenyan Zhang
- Center for Pathogen Biology and Infectious Diseases, Institute of Virology and AIDS Research, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
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A Single Amino Acid Switch in the Adenoviral DNA Binding Protein Abrogates Replication Center Formation and Productive Viral Infection. mBio 2022; 13:e0014422. [PMID: 35254132 PMCID: PMC9040859 DOI: 10.1128/mbio.00144-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Adenoviruses are very efficient high-capacity vaccine vectors and are common gene delivery systems. Despite their extensive use in preclinical models and clinical trials over the past decades, adenoviral vectors still require optimization. To achieve that, more thorough characterizations of adenoviral genes and gene products, as well as pathogen-host interactions, are indispensable. The adenoviral DNA binding protein (DBP) is a key regulatory protein involved in various cellular and viral processes. Here, we show that single amino acid exchange mutations in human adenovirus C5 (HAdV-C5) DBP strongly influence adenoviral replication by altering interaction with the cellular ubiquitination machinery. Specifically, phenotypic analyses of DBP mutants demonstrate that single amino acid substitutions can regulate interactions with the cellular USP7 deubiquitinase, impede viral DNA synthesis, and completely abolish viral late protein expression and progeny production. Importantly, cells infected with the DBP mutant UBM5 consistently lack DBP-positive replication centers (RCs), which are usually formed during the transition from the early to the late phase of infection. Our findings demonstrate that DBP regulates a key step at the onset of the late phase of infection and that this activity is unambiguously linked to the formation and integrity of viral RCs. These data provide the experimental basis for future work that targets DBP and its interference with the formation of viral RCs during productive infection. Consequently, this work will have immediate impact on DNA virus and adenovirus research in general and, potentially, also on safety optimization of existing and development of novel adenoviral vectors and anti-adenoviral compounds.
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Zhou L, Ouyang T, Li M, Hong T, Mhs A, Meng W, Zhang N. Ubiquitin-Specific Peptidase 7: A Novel Deubiquitinase That Regulates Protein Homeostasis and Cancers. Front Oncol 2021; 11:784672. [PMID: 34869041 PMCID: PMC8640129 DOI: 10.3389/fonc.2021.784672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/26/2021] [Indexed: 12/23/2022] Open
Abstract
Ubiquitin-Specific Peptidase 7 (USP7), or herpes virus-associated protease (HAUSP), is the largest family of the deubiquitinating enzymes (DUBs). Recent studies have shown that USP7 plays a vital role in regulating various physiological and pathological processes. Dysregulation of these processes mediated by USP7 may contribute to many diseases, such as cancers. Moreover, USP7 with aberrant expression levels and abnormal activity are found in cancers. Therefore, given the association between USP7 and cancers, targeting USP7 could be considered as an attractive and potential therapeutic approach in cancer treatment. This review describes the functions of USP7 and the regulatory mechanisms of its expression and activity, aiming to emphasize the necessity of research on USP7, and provide a better understanding of USP7-related biological processes and cancer.
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Affiliation(s)
- Lin Zhou
- First Clinical Medical College, Nanchang University, Nanchang, China
| | - Taohui Ouyang
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Meihua Li
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Tao Hong
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Alriashy Mhs
- Department of Neurosurgery, Huashan Hospital of Fudan University, Shanghai, China
| | - Wei Meng
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Na Zhang
- Department of Neurology, The First Affiliated Hospital of Nanchang University, Nanchang, China
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The ORF45 Protein of Kaposi Sarcoma-Associated Herpesvirus Is an Inhibitor of p53 Signaling during Viral Reactivation. J Virol 2021; 95:e0145921. [PMID: 34523970 DOI: 10.1128/jvi.01459-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Kaposi sarcoma-associated herpesvirus (KSHV) is a carcinogenic double-stranded DNA virus and the etiological agent of Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman's disease (MCD). To prevent premature apoptosis and support its replication cycle, KSHV expresses a series of open reading frames (ORFs) that regulate signaling by the p53 tumor suppressor protein. Here, we describe a novel viral inhibitor of p53 encoded by KSHV ORF45 and identify its mechanism of action. ORF45 binds to p53 and prevents its interactions with USP7, a p53 deubiquitinase. This results in decreased p53 accumulation, localization of p53 to the cytoplasm, and diminished transcriptional activity. IMPORTANCE Unlike in other cancers, the tumor suppressor protein p53 is rarely mutated in Kaposi sarcoma (KS). Rather, Kaposi sarcoma-associated herpesvirus (KSHV) inactivates p53 through multiple viral proteins. One possible therapeutic approach to KS is the activation of p53, which would result in apoptosis and tumor regression. In this regard, it is important to understand all the mechanisms used by KSHV to modulate p53 signaling. This work describes a novel inhibitor of p53 signaling and a potential drug target, ORF45, and identifies the mechanisms of its action.
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9
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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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10
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Bojagora A, Saridakis V. USP7 manipulation by viral proteins. Virus Res 2020; 286:198076. [DOI: 10.1016/j.virusres.2020.198076] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 05/14/2020] [Accepted: 06/24/2020] [Indexed: 01/27/2023]
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The Ubiquitin-Specific Protease Usp7, a Novel Merkel Cell Polyomavirus Large T-Antigen Interaction Partner, Modulates Viral DNA Replication. J Virol 2020; 94:JVI.01638-19. [PMID: 31801860 DOI: 10.1128/jvi.01638-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/01/2019] [Indexed: 02/06/2023] Open
Abstract
Merkel cell polyomavirus (MCPyV) is the major cause for Merkel cell carcinoma (MCC), a rare but highly aggressive skin cancer predominantly found in elderly and immunosuppressed patients. The early viral gene products large T-antigen (LT) and small T-antigen (sT) are important for efficient viral DNA replication, and both contribute to transformation processes. These functions are executed mainly through interactions with host factors. Here, we identify the cellular ubiquitin-specific processing protease 7 (Usp7) as a new interaction partner of the MCPyV LT. Using glutathione S-transferase pulldown experiments, we show that MCPyV LT directly binds to Usp7 and that N- as well as C-terminal regions of LT bind to the TRAF (tumor necrosis factor receptor-associated) domain of Usp7. We demonstrate that endogenous Usp7 coprecipitates with MCPyV T-antigens and relocalizes to viral DNA replication centers in cells actively replicating MCPyV genomes. We show that Usp7 does not alter ubiquitination levels of the T-antigens; however, Usp7 binding increases the binding affinity of LT to the origin of replication, thereby negatively regulating viral DNA replication. Together, these data identify Usp7 as a restriction factor of MCPyV replication. In contrast to other DNA viruses, Usp7 does not affect MCPyV gene expression via its ubiquitination activity but influences MCPyV DNA replication solely via a novel mechanism that modulates binding of LT to viral DNA.IMPORTANCE MCPyV is the only human polyomavirus that is associated with cancer; the majority of Merkel cell cancers have a viral etiology. While much emphasis was placed on investigations to understand the transformation process by MCPyV oncoproteins and cellular factors, we have only limited knowledge of cellular factors participating in the MCPyV life cycle. Here, we describe Usp7, a cellular deubiquitination enzyme, as a new factor involved in MCPyV replication. Usp7 is known in the context of large DNA tumor viruses, Epstein-Barr virus (EBV) and Kaposi's sarcoma herpesvirus, to restrict viral replication. Similar to EBV, where Usp7 binding to EBNA1 increases EBNA1 binding affinity to viral DNA, we find MCPyV LT binding to the origin of replication to be increased in the presence of Usp7, resulting in restriction of viral DNA replication. However, Usp7-induced restriction of MCPyV replication is independent of its enzymatic activity, thereby constituting a novel mechanism of Usp7-induced restriction of viral replication.
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12
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Xiang Q, Ju H, Nicholas J. USP7-Dependent Regulation of TRAF Activation and Signaling by a Viral Interferon Regulatory Factor Homologue. J Virol 2020; 94:e01553-19. [PMID: 31666375 PMCID: PMC6955280 DOI: 10.1128/jvi.01553-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 10/22/2019] [Indexed: 01/12/2023] Open
Abstract
Human herpesvirus 8 (HHV-8) encodes four viral interferon regulatory factors (vIRFs 1 to 4), all of which are expressed during lytic replication and inhibit a variety of antiviral signaling pathways. Viral IRFs 1, 2, and 3 are also expressed during latency in primary effusion lymphoma (PEL) cells, and vIRF-1 and vIRF-3 have been reported to promote PEL cell viability. Viral IRFs 1, 3, and 4 are known to interact with ubiquitin-specific protease 7 (USP7); interactions of vIRF-1 and vIRF-3 with USP7 promote PEL cell viability and regulate productive replication. Here, we report that vIRF-2 also targets USP7, utilizing a PSTS motif matching the USP7 N-terminal domain-binding A/PxxS consensus, but uniquely requires catalytic domain residues for intracellular interaction. In functional and mechanistic analyses, tumor necrosis factor receptor-associated factor (TRAF)-mediated signaling and associated polyubiquitination of TRAFs 3 and 6, specifically, were regulated negatively by USP7 and positively by vIRF-2-USP7 interaction, the latter competing for USP7-TRAF association. Using depletion, depletion-complementation, and targeted mutagenesis approaches, vIRF-2 was determined to promote latent PEL cell viability, likely independently of USP7 interaction, while lytic replication was inhibited by vIRF-2, in part or in whole via USP7 interaction. Together, our data identify a new molecular determinant of USP7 recognition, TRAF3/6-specific targeting by the deubiquitinase, associated activation of these TRAFs by vIRF-2, and activities of vIRF-2 and vIRF-2-USP7 interaction in HHV-8 latent and lytic biology.IMPORTANCE Human herpesvirus 8-encoded IRF homologues were the first to be identified in a virus. Through inhibitory interactions with cellular IRFs and other mediators of antiviral signaling, the vIRFs are believed to be essential for productive replication and also for latency in particular cell types. The deubiquitinase USP7 is a regulator of key cellular pathways, modulates HHV-8 latent and lytic infection, and is targeted by vIRFs 1, 3, and 4. Here, we report that vIRF-2 also interacts with USP7, via a means distinguishable from USP7 interactions with other vIRFs and other proteins, that this interaction modulates antiviral signaling via disruption of USP7 interactions with innate immune signaling proteins TRAF3 and TRAF6, and that vIRF-2 targeting of USP7 regulates HHV-8 productive replication. The presented data are the first to identify vIRF-2 targeting of USP7 and its role in HHV-8 biology, expanding our understanding of the repertoire and importance of virus-host interactions.
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Affiliation(s)
- Qiwang Xiang
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hyunwoo Ju
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - John Nicholas
- Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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13
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Gagarina V, Bojagora A, Lacdao IK, Luthra N, Pfoh R, Mohseni S, Chaharlangi D, Tan N, Saridakis V. Structural Basis of the Interaction Between Ubiquitin Specific Protease 7 and Enhancer of Zeste Homolog 2. J Mol Biol 2019; 432:897-912. [PMID: 31866294 DOI: 10.1016/j.jmb.2019.12.026] [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] [Received: 08/12/2019] [Revised: 11/26/2019] [Accepted: 12/12/2019] [Indexed: 11/25/2022]
Abstract
USP7 is a deubiquitinase that regulates many diverse cellular processes, including tumor suppression, epigenetics, and genome stability. Several substrates, including GMPS, UHRF1, and ICP0, were shown to bear a specific KxxxK motif that interacts within the C-terminal region of USP7. We identified a similar motif in Enhancer of Zeste 2 (EZH2), the histone methyltransferase found within Polycomb Repressive Complex 2 (PRC2). PRC2 is responsible for the methylation of Histone 3 Lys27 (H3K27) leading to gene silencing. GST pull-down and coimmunoprecipitation experiments showed that USP7 interacts with EZH2. We determined the structural basis of interaction between USP7 and EZH2 and identified residues mediating the interaction. Mutations in these critical residues disrupted the interaction between USP7 and EZH2. Furthermore, USP7 silencing and knockout experiments showed decreased EZH2 levels in HCT116 carcinoma cells. Finally, we demonstrated decreased H3K27Me3 levels in HCT116 USP7 knockout cells. These results indicate that USP7 interacts with EZH2 and regulates both its stability and function.
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Affiliation(s)
- Varvara Gagarina
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Anna Bojagora
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Ira Kay Lacdao
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Niharika Luthra
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Roland Pfoh
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Sadaf Mohseni
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Danica Chaharlangi
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Nadine Tan
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada
| | - Vivian Saridakis
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J1P3, Canada.
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14
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Xin S, Du S, Liu L, Xie Y, Zuo L, Yang J, Hu J, Yue W, Zhang J, Cao P, Zhu F, Lu J. Epstein-Barr Virus Nuclear Antigen 1 Recruits Cyclophilin A to Facilitate the Replication of Viral DNA Genome. Front Microbiol 2019; 10:2879. [PMID: 31921057 PMCID: PMC6923202 DOI: 10.3389/fmicb.2019.02879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/28/2019] [Indexed: 12/18/2022] Open
Abstract
Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1)-mediated DNA episomal genome replication and persistence are essential for the viral pathogenesis. Cyclophilin A (CYPA) is upregulated in EBV-associated nasopharyngeal carcinoma (NPC) with unknown roles. In the present approach, cytosolic CYPA was found to be bound with EBNA1 into the nucleus. The amino acid 376-459 of the EBNA1 domain was important for the binding. CYPA depletion attenuated and ectopic CYPA expression improved EBNA1 expression in EBV-positive cells. The loss of viral copy number was also accelerated by CYPA consumption in daughter cells during culture passages. Mechanistically, CYPA mediated the connection of EBNA1 with oriP (origin of EBV DNA replication) and subsequent oriP transcription, which is a key step for the initiation of EBV genome replication. Moreover, CYPA overexpression markedly antagonized the connection of EBNA1 to Ubiquitin-specific protease 7 (USP7), which is a strong host barrier with a role of inhibiting EBV genome replication. The PPIase activity of CYPA was required for the promotion of oriP transcription and antagonism with USP7. The results revealed a strategy that EBV recruited a host factor to counteract the host defense, thus facilitating its own latent genome replication. This study provides a new insight into EBV pathogenesis and potential virus-targeted therapeutics in EBV-associated NPC, in which CYPA is upregulated at all stages.
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Affiliation(s)
- Shuyu Xin
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Shujuan Du
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Lingzhi Liu
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Yan Xie
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Lielian Zuo
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Yang
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China
| | - Jingjin Hu
- Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Wenxing Yue
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Jing Zhang
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Pengfei Cao
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
| | - Fanxiu Zhu
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Biological Sciences, Florida State University, Tallahassee, FL, United States
| | - Jianhong Lu
- NHC Key Laboratory of Carcinogenesis, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital, Central South University, Changsha, China.,Department of Medical Microbiology, School of Basic Medical Science, Central South University, Changsha, China
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15
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Regulation of the Ebola Virus VP24 Protein by SUMO. J Virol 2019; 94:JVI.01687-19. [PMID: 31597768 DOI: 10.1128/jvi.01687-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 10/02/2019] [Indexed: 12/15/2022] Open
Abstract
Some viruses take advantage of conjugation of ubiquitin or ubiquitin-like proteins to enhance their own replication. One example is Ebola virus, which has evolved strategies to utilize these modification pathways to regulate the viral proteins VP40 and VP35 and to counteract the host defenses. Here, we show a novel mechanism by which Ebola virus exploits the ubiquitin and SUMO pathways. Our data reveal that minor matrix protein VP24 of Ebola virus is a bona fide SUMO target. Analysis of a SUMOylation-defective VP24 mutant revealed a reduced ability to block the type I interferon (IFN) pathway and to inhibit IFN-mediated STAT1 nuclear translocation, exhibiting a weaker interaction with karyopherin 5 and significantly diminished stability. Using glutathione S-transferase (GST) pulldown assay, we found that VP24 also interacts with SUMO in a noncovalent manner through a SIM domain. Mutation of the SIM domain in VP24 resulted in a complete inability of the protein to downmodulate the IFN pathway and in the monoubiquitination of the protein. We identified SUMO deubiquitinating enzyme ubiquitin-specific-processing protease 7 (USP7) as an interactor and a negative modulator of VP24 ubiquitination. Finally, we show that mutation of one ubiquitination site in VP24 potentiates the IFN modulatory activity of the viral protein and its ability to block IFN-mediated STAT1 nuclear translocation, pointing to the ubiquitination of VP24 as a negative modulator of the VP24 activity. Altogether, these results indicate that SUMO interacts with VP24 and promotes its USP7-mediated deubiquitination, playing a key role in the interference with the innate immune response mediated by the viral protein.IMPORTANCE The Ebola virus VP24 protein plays a critical role in escape of the virus from the host innate immune response. Therefore, deciphering the molecular mechanisms modulating VP24 activity may be useful to identify potential targets amenable to therapeutics. Here, we identify the cellular proteins USP7, SUMO, and ubiquitin as novel interactors and regulators of VP24. These interactions may represent novel potential targets to design new antivirals with the ability to modulate Ebola virus replication.
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16
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Yuan Y, Miao Y, Zeng C, Liu J, Chen X, Qian L, Wang X, Qian F, Yu Z, Wang J, Qian G, Fu Q, Lv H, Zheng H. Small-molecule inhibitors of ubiquitin-specific protease 7 enhance type-I interferon antiviral efficacy by destabilizing SOCS1. Immunology 2019; 159:309-321. [PMID: 31691271 DOI: 10.1111/imm.13147] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/13/2019] [Accepted: 11/03/2019] [Indexed: 12/20/2022] Open
Abstract
Type-I interferons (IFN-I) are used as common antiviral drugs for a range of viral diseases in clinic. However, the antiviral efficacy of IFN-I is largely restricted by negative regulators of IFN-I signaling in cells. Therefore, identification of intracellular inhibitors of IFN-I signaling is important for developing novel targets to improve IFN-I antiviral therapy. In this study, we report that the deubiquitinase ubiquitin-specific protease 7 (USP7) negatively regulates IFN-I-mediated antiviral activity. USP7 physically interacts with suppressor of cytokine signaling 1 (SOCS1) and enhances SOCS1 protein stability by deubiquitination effects, which in turn restricts IFN-I-induced activation of Janus kinase-signal transducer and activator of transcription 1 signaling. Interestingly, viral infection up-regulates USP7 and therefore facilitates viral immune evasion. Importantly, the USP7 small-molecule inhibitors P5091 and P22077 inhibit SOCS1 expression and enhance IFN-I antiviral efficacy. Our findings identify a novel regulator of IFN-I antiviral activity and reveal that USP7 inhibitors could be potential enhancement agents for improving IFN-I antiviral therapy.
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Affiliation(s)
- Yukang Yuan
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Ying Miao
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Chenhua Zeng
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Jin Liu
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China.,The Affiliated Infectious Diseases Hospital of Soochow University, Suzhou, China
| | - Xiangjie Chen
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Liping Qian
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Xiaofang Wang
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Feng Qian
- The Affiliated Infectious Diseases Hospital of Soochow University, Suzhou, China
| | - Zhengyuan Yu
- Department of Oncology, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jun Wang
- Department of Intensive Care Medicine, the First Affiliated Hospital of Soochow University, Suzhou, China
| | - Guanghui Qian
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, China
| | - Qian Fu
- Soochow University Library, Suzhou, China
| | - Haitao Lv
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, China
| | - Hui Zheng
- Institutes of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
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17
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Kosulin K, Lam E, Heim A, Dobner T, Rodríguez E. Broad-spectrum antiviral activity of the deubiquitinase inhibitor HBX against human adenoviruses. Antivir Ther 2019; 23:475-483. [PMID: 29557344 DOI: 10.3851/imp3230] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND Human adenoviral (HAdV) infections are usually mild and self-limited, however, some infections from species A, B, C, D and E, can cause severe illnesses, which have raised public health concerns over the past few years. Current available antiviral therapies have limited efficacy and severe toxicity; therefore, finding new targets for specific anti-adenoviral drug design is urgently needed. Our previous work showed that the small molecule compound, HBX, inhibits HAdV type 5 (species C, HAdV-C5) replication and oncogenic transformation through inhibition of the cellular pro-viral factor ubiquitin-specific protease 7 (USP7). Here, we have tested the ability of HBX to inhibit other HAdV species, as well as different clinical isolates that are the cause of severe infections. METHODS We treated HAdV-infected A549 cells with different concentrations of HBX and analysed the antiviral efficacy of the drug by determining the half maximal inhibitory concentration (IC50) necessary to decrease both viral genome copies and virus progeny production at different time points after infection. RESULTS In addition to its effect on HAdV-C5, HBX was able to significantly inhibit virus genome replication and progeny release of all adenovirus types tested, with the exception of types 12 and 31, from species A. Of note, clinical isolates were more sensitive to HBX treatment than their prototype strains. CONCLUSIONS These results point to HBX as a promising broad-spectrum anti-adenoviral drug, opening new opportunities to prevent severe adenoviral infections and to improve their treatment.
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Affiliation(s)
- Karin Kosulin
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany.,Present address: Children's Cancer Research Institute, Vienna, Austria
| | - Elena Lam
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Albert Heim
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Thomas Dobner
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Estefanía Rodríguez
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
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18
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Wang Z, Kang W, You Y, Pang J, Ren H, Suo Z, Liu H, Zheng Y. USP7: Novel Drug Target in Cancer Therapy. Front Pharmacol 2019; 10:427. [PMID: 31114498 PMCID: PMC6502913 DOI: 10.3389/fphar.2019.00427] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/04/2019] [Indexed: 12/22/2022] Open
Abstract
Ubiquitin specific protease 7 (USP7) is one of the deubiquitinating enzymes (DUB) that erases ubiquitin and protects substrate protein from degradation. Full activity of USP7 requires the C-terminal Ub-like domains fold back onto the catalytic domain, allowing the remodeling of the active site to a catalytically competent state by the C-terminal peptide. Until now, numerous proteins have been identified as substrates of USP7, which play a key role in cell cycle, DNA repair, chromatin remodeling, and epigenetic regulation. Aberrant activation or overexpression of USP7 may promote oncogenesis and viral disease, making it a target for therapeutic intervention. Currently, several synthetic small molecules have been identified as inhibitors of USP7, and applied in the treatment of diverse diseases. Hence, USP7 may be a promising therapeutic target for the treatment of cancer.
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Affiliation(s)
- Zhiru Wang
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China.,Pathology, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Wenting Kang
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
| | - Yinghua You
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
| | - Jingru Pang
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
| | - Hongmei Ren
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
| | - Zhenhe Suo
- Pathology, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Hongmin Liu
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
| | - Yichao Zheng
- School of Pharmaceutical Sciences, Zhenghzou University, Zhengzhou, China.,Collaborative Innovation Centre of New Drug Research and Safety Evaluation, Henan Province, and Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, and Key Laboratory of Henan Province for Drug Quality and Evaluation, Ministry of Education of China, Zhengzhou, China
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19
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Zhang F, Liang D, Lin X, Zou Z, Sun R, Wang X, Liang X, Kaye KM, Lan K. NDRG1 facilitates the replication and persistence of Kaposi's sarcoma-associated herpesvirus by interacting with the DNA polymerase clamp PCNA. PLoS Pathog 2019; 15:e1007628. [PMID: 30811506 PMCID: PMC6411202 DOI: 10.1371/journal.ppat.1007628] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/11/2019] [Accepted: 02/08/2019] [Indexed: 02/07/2023] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) latently infects host cells and establishes lifelong persistence as an extra-chromosomal episome in the nucleus. To persist in proliferating cells, the viral genome typically replicates once per cell cycle and is distributed into daughter cells. This process involves host machinery utilized by KSHV, however the underlying mechanisms are not fully elucidated. In present study, we found that N-Myc downstream regulated gene 1 (NDRG1), a cellular gene known to be non-detectable in primary B cells and endothelial cells which are the major cell types for KSHV infection in vivo, was highly upregulated by KSHV in these cells. We further demonstrated that the high expression of NDRG1 was regulated by latency-associated nuclear antigen (LANA), the major viral latent protein which tethers the viral genome to host chromosome and plays an essential role in viral genome maintenance. Surprisingly, knockdown of NDRG1 in KSHV latently infected cells resulted in a significant decrease of viral genome copy number in these cells. Interestingly, NDRG1 can directly interact with proliferating cell nuclear antigen (PCNA), a cellular protein which functions as a DNA polymerase clamp during DNA replication. Intriguingly, we found that NDRG1 forms a complex with LANA and PCNA and serves as a scaffold protein bridging these two proteins. We further demonstrated that NDRG1 is critical for mediating LANA to recruit PCNA onto terminal repeat (TR) of KSHV genome, and facilitates viral DNA replication and episome persistence. Taken together, our findings suggest that NDRG1 plays an important role in KSHV viral genome replication, and provide new clues for understanding of KSHV persistence.
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Affiliation(s)
- Fang Zhang
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Deguang Liang
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Xiaoxi Lin
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Zhe Zou
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Rui Sun
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Xing Wang
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Xiaozhen Liang
- CAS Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Kenneth M. Kaye
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Ke Lan
- State Key Laboratory of Virology, College of Life Sciences, Medical Research Institute, Wuhan University, Wuhan, China
- * E-mail:
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20
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Georges A, Coyaud E, Marcon E, Greenblatt J, Raught B, Frappier L. USP7 Regulates Cytokinesis through FBXO38 and KIF20B. Sci Rep 2019; 9:2724. [PMID: 30804394 PMCID: PMC6389929 DOI: 10.1038/s41598-019-39368-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/18/2019] [Indexed: 01/13/2023] Open
Abstract
The ubiquitin specific protease 7 (USP7 or HAUSP) is known to regulate a variety of cellular processes by binding and deubiquitylating specific target proteins. To gain a more comprehensive understanding of its interactions and functions, we used affinity purification coupled to mass spectrometry to profile USP7 interactions. This revealed a novel interaction with FBXO38, a poorly characterized F-box protein. We showed that USP7 stabilizes FBXO38 dependent on its catalytic activity by protecting FBXO38 from proteasomal degradation. We used a BioID approach to profile the protein interactions (and putative functions) of FBXO38, revealing an interaction with KIF20B, a Kinesin-6 protein required for efficient cytokinesis. FBXO38 was shown to function independently from an SCF complex to stabilize KIF20B. Consequently, depletion of either FBXO38 or USP7 led to dramatic decreases in KIF20B levels and KIF20B at the midbody, which were manifested in cytokinetic defects. Furthermore, cytokinetic defects associated with USP7 silencing were rescued by restoring FBXO38 or KIF20B. The results indicate a novel mechanism of regulating cytokinesis through USP7 and FBXO38.
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Affiliation(s)
- Anna Georges
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Etienne Coyaud
- The Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, M5G 1L7, Canada
| | - Edyta Marcon
- Donnelly Centre, University of Toronto, Toronto, Canada
| | - Jack Greenblatt
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.,Donnelly Centre, University of Toronto, Toronto, Canada
| | - Brian Raught
- The Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Lori Frappier
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
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21
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USP7: Structure, substrate specificity, and inhibition. DNA Repair (Amst) 2019; 76:30-39. [PMID: 30807924 DOI: 10.1016/j.dnarep.2019.02.005] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 02/07/2019] [Indexed: 12/24/2022]
Abstract
Turnover of cellular proteins is regulated by Ubiquitin Proteasome System (UPS). Components of this pathway, including the proteasome, ubiquitinating enzymes and deubiquitinating enzymes, are highly specialized and tightly regulated. In this mini-review we focus on the de-ubiquitinating enzyme USP7, and summarize latest advances in understanding its structure, substrate specificity and relevance to human cancers. There is increasing interest in UPS components as targets for cancer therapy and here we also overview the recent progress in the development of small molecule inhibitors that target USP7.
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22
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Georges A, Marcon E, Greenblatt J, Frappier L. Identification and Characterization of USP7 Targets in Cancer Cells. Sci Rep 2018; 8:15833. [PMID: 30367141 PMCID: PMC6203733 DOI: 10.1038/s41598-018-34197-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/12/2018] [Indexed: 02/07/2023] Open
Abstract
The ubiquitin specific protease, USP7, regulates multiple cellular pathways relevant for cancer through its ability to bind and sometimes stabilize specific target proteins through deubiquitylation. To gain a more complete profile of USP7 interactions in cancer cells, we performed affinity purification coupled to mass spectrometry to identify USP7 binding targets in gastric carcinoma cells. This confirmed reported associations of USP7 with USP11, PPM1G phosphatase and TRIP12 E3 ubiquitin ligase as well as identifying novel interactions with two DEAD/DEAH-box RNA helicases, DDX24 and DHX40. Using USP7 binding pocket mutants, we show that USP11, PPM1G, TRIP12 and DDX24 bind USP7 through its TRAF domain binding pocket, while DHX40 interacts with USP7 through a distinct binding pocket in the Ubl2 domain. P/A/ExxS motifs in USP11 and DDX24 that are critical for USP7 binding were also identified. Modulation of USP7 expression levels and inhibition of USP7 catalytic activity in multiple cells lines showed that USP7 consistently stabilizes DDX24, DHX40 and TRIP12 dependent on its catalytic activity, while USP11 and PPM1G levels were not consistently affected. Our study better defines the mechanisms of USP7 interaction with known targets and identifies DDX24 and DHX40 as new targets that are specifically bound and regulated by USP7.
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Affiliation(s)
- Anna Georges
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Edyta Marcon
- Donnelly Centre, University of Toronto, Toronto, Canada
| | - Jack Greenblatt
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.,Donnelly Centre, University of Toronto, Toronto, Canada
| | - Lori Frappier
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
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23
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Ubiquitination at the interface of tumor viruses and DNA damage responses. Curr Opin Virol 2018; 32:40-47. [PMID: 30261451 DOI: 10.1016/j.coviro.2018.08.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 08/31/2018] [Indexed: 01/09/2023]
Abstract
Viruses exploit cellular ubiquitination machinery to shape the host proteome and promote productive infection. Among the cellular processes influenced by viral manipulation of ubiquitination is the DNA damage response (DDR), a network of cellular signaling pathways that sense and respond to genomic damage. This host-pathogen interaction is particularly important during virus replication and transformation by DNA tumor viruses. Manipulating DDR pathways can promote virus replication but also impacts host genomic instability, potentially leading to cellular transformation and tumor formation. We review ways in which viruses are known to hijack the cellular ubiquitin system to reshape host DDR pathways.
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24
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Emerging insights into HAUSP (USP7) in physiology, cancer and other diseases. Signal Transduct Target Ther 2018; 3:17. [PMID: 29967688 PMCID: PMC6023882 DOI: 10.1038/s41392-018-0012-y] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 02/13/2018] [Accepted: 02/23/2018] [Indexed: 12/13/2022] Open
Abstract
Herpesvirus-associated ubiquitin-specific protease (HAUSP) is a USP family deubiquitinase. HAUSP is a protein of immense biological importance as it is involved in several cellular processes, including host-virus interactions, oncogenesis and tumor suppression, DNA damage and repair processes, DNA dynamics and epigenetic modulations, regulation of gene expression and protein function, spatio-temporal distribution, and immune functions. Since its discovery in the late 1990s as a protein interacting with a herpes virus regulatory protein, extensive studies have assessed its complex roles in p53-MDM2-related networks, identified numerous additional interacting partners, and elucidated the different roles of HAUSP in the context of cancer, development, and metabolic and neurological pathologies. Recent analyses have provided new insights into its biochemical and functional dynamics. In this review, we provide a comprehensive account of our current knowledge about emerging insights into HAUSP in physiology and diseases, which shed light on fundamental biological questions and promise to provide a potential target for therapeutic intervention. Improved understandings of a molecular-tag-removing enzyme could lead to the development of therapies for many diseases. Dr. Mrinal K Ghosh of the Council of Scientific and Industrial Research-Indian Institute of Chemical Biology (CSIR-IICB) and colleagues reviewed 20 years of research on herpesvirus-associated ubiquitin-specific protease (HAUSP), involved in a wide range of cellular processes through its role in removing the ubiquitin from molecules, thus signaling their fate. It was first discovered in/as a herpes virus infected cells, ultimately enhancing infection. It was later found to have a wide range of functions depending on the molecules it interacts with under normal physiological and disease conditions. Targeting HAUSP with drugs shows promise for suppressing prostate, lung, colon, breast, blood, and other cancers. It could also impact treatment of neurological conditions such as Huntington’s disease, and metabolic disorders, such as diabetes.
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Yeasmin Khusbu F, Chen FZ, Chen HC. Targeting ubiquitin specific protease 7 in cancer: A deubiquitinase with great prospects. Cell Biochem Funct 2018; 36:244-254. [PMID: 29781103 DOI: 10.1002/cbf.3336] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/21/2018] [Accepted: 04/23/2018] [Indexed: 12/20/2022]
Abstract
Deubiquitinase (DUB)-mediated cleavage of ubiquitin chain balances ubiquitination and deubiquitination for determining protein fate. USP7 is one of the best characterized DUBs and functionally important. Numerous proteins have been identified as potential substrates and binding partners of USP7; those play crucial roles in diverse array of cellular and biological processes including tumour suppression, cell cycle, DNA repair, chromatin remodelling, and epigenetic regulation. This review aims at summarizing the current knowledge of this wide association of USP7 with many cellular processes that enlightens the possibility of abnormal USP7 activity in promoting oncogenesis and the importance of identification of specific inhibitors.
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Affiliation(s)
- Farjana Yeasmin Khusbu
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Fang-Zhi Chen
- Department of Urology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Han-Chun Chen
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Central South University, Changsha, Hunan, China
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Mariggiò G, Koch S, Schulz TF. Kaposi sarcoma herpesvirus pathogenesis. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0275. [PMID: 28893942 PMCID: PMC5597742 DOI: 10.1098/rstb.2016.0275] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2017] [Indexed: 12/15/2022] Open
Abstract
Kaposi sarcoma herpesvirus (KSHV), taxonomical name human gammaherpesvirus 8, is a phylogenetically old human virus that co-evolved with human populations, but is now only common (seroprevalence greater than 10%) in sub-Saharan Africa, around the Mediterranean Sea, parts of South America and in a few ethnic communities. KSHV causes three human malignancies, Kaposi sarcoma, primary effusion lymphoma, and many cases of the plasmablastic form of multicentric Castleman's disease (MCD) as well as occasional cases of plasmablastic lymphoma arising from MCD; it has also been linked to rare cases of bone marrow failure and hepatitis. As it has colonized humans physiologically for many thousand years, cofactors are needed to allow it to unfold its pathogenic potential. In most cases, these include immune defects of genetic, iatrogenic or infectious origin, and inflammation appears to play an important role in disease development. Our much improved understanding of its life cycle and its role in pathogenesis should now allow us to develop new therapeutic strategies directed against key viral proteins or intracellular pathways that are crucial for virus replication or persistence. Likewise, its limited (for a herpesvirus) distribution and transmission should offer an opportunity for the development and use of a vaccine to prevent transmission. This article is part of the themed issue ‘Human oncogenic viruses’.
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Affiliation(s)
- Giuseppe Mariggiò
- Institute of Virology, Hannover Medical School, Carl Neuberg Strasse 1, 30625 Hannover, Germany.,German Centre for Infection Research, Hannover-Braunschweig site, Hannover, Germany
| | - Sandra Koch
- Institute of Virology, Hannover Medical School, Carl Neuberg Strasse 1, 30625 Hannover, Germany.,German Centre for Infection Research, Hannover-Braunschweig site, Hannover, Germany
| | - Thomas F Schulz
- Institute of Virology, Hannover Medical School, Carl Neuberg Strasse 1, 30625 Hannover, Germany .,German Centre for Infection Research, Hannover-Braunschweig site, Hannover, Germany
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Human Herpesvirus 8 Interferon Regulatory Factors 1 and 3 Mediate Replication and Latency Activities via Interactions with USP7 Deubiquitinase. J Virol 2018; 92:JVI.02003-17. [PMID: 29343584 DOI: 10.1128/jvi.02003-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 01/12/2018] [Indexed: 12/14/2022] Open
Abstract
Human herpesvirus 8 (HHV-8) encodes four viral interferon regulatory factors (vIRF-1 to -4) that likely function to suppress innate immune and cellular stress responses through inhibitory interactions with various cellular proteins involved in these activities. It is notable that vIRF-1 and -4 have been reported to interact with the deubiquitinase ubiquitin-specific protease 7 (USP7), substrates of which include p53 and the p53-targeting and -destabilizing ubiquitin E3 ligase MDM2. Structural studies of vIRF-1 and vIRF-4 USP7 binding sequences in association with USP7 have been reported; both involve interactions with N-terminal-domain residues of USP7 via EGPS and ASTS motifs in vIRF-1 and vIRF-4, respectively, but vIRF-4 residues also contact the catalytic site. However, the biological activities of vIRF-1 and vIRF-4 via USP7 interactions are unknown. Here, we report that vIRF-3, which is latently, as well as lytically, expressed in HHV-8-infected primary effusion lymphoma (PEL) cells, also interacts with USP7-via duplicated EGPS motifs-and that this interaction is important for PEL cell growth and viability. The interaction also contributes to suppression of productive virus replication by vIRF-3, which we identify here. We further show that vIRF-1, which is expressed at low levels in PEL latency, promotes latent PEL cell viability and that this activity and vIRF-1-promoted productive replication (reported previously) involve EGPS motif-mediated USP7 targeting by vIRF-1. This study is the first to identify latent and lytic functions of vIRF-1 and vIRF-3, respectively, and to address the biological activities of these vIRFs through their interactions with USP7.IMPORTANCE HHV-8 is associated with Kaposi's sarcoma, primary effusion lymphoma (PEL), and multicentric Castleman's disease; both latent and lytic viral functions are believed to contribute. Viral interferon regulatory factors specified by HHV-8 are thought to be critically important for successful productive replication through suppression of innate immune and stress responses triggered by the lytic cycle. Latently expressed vIRF-3 contributes significantly to PEL cell survival. Here, we identify ubiquitin-specific protease 7 (USP7) deubiquitinase targeting by vIRF-3 (in addition to previously reported USP7 binding by vIRF-1 and vIRF-4); the importance of vIRF-1 and vIRF-3 interactions with USP7 for latent PEL cell growth and viability; and the positive and negative contributions, respectively, of USP7 targeting by vIRF-1 and vIRF-3 to HHV-8 productive replication. This is the first report of the biological importance of vIRF-1 in PEL cell latency, the modulation of productive replication by vIRF-3, and the contributions of vIRF-USP7 interactions to HHV-8 biology.
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Gavory G, O'Dowd CR, Helm MD, Flasz J, Arkoudis E, Dossang A, Hughes C, Cassidy E, McClelland K, Odrzywol E, Page N, Barker O, Miel H, Harrison T. Discovery and characterization of highly potent and selective allosteric USP7 inhibitors. Nat Chem Biol 2017; 14:118-125. [PMID: 29200206 DOI: 10.1038/nchembio.2528] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 10/18/2017] [Indexed: 12/26/2022]
Abstract
Given the importance of ubiquitin-specific protease 7 (USP7) in oncogenic pathways, identification of USP7 inhibitors has attracted considerable interest. Despite substantial efforts, however, the development of validated deubiquitinase (DUB) inhibitors that exhibit drug-like properties and a well-defined mechanism of action has proven particularly challenging. In this article, we describe the identification, optimization and detailed characterization of highly potent (IC50 < 10 nM), selective USP7 inhibitors together with their less active, enantiomeric counterparts. We also disclose, for the first time, co-crystal structures of a human DUB enzyme complexed with small-molecule inhibitors, which reveal a previously undisclosed allosteric binding site. Finally, we report the identification of cancer cell lines hypersensitive to USP7 inhibition (EC50 < 30 nM) and demonstrate equal or superior activity in these cell models compared to clinically relevant MDM2 antagonists. Overall, these findings demonstrate the tractability and druggability of DUBs, and provide important tools for additional target validation studies.
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Affiliation(s)
- Gerald Gavory
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Colin R O'Dowd
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Matthew D Helm
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Jakub Flasz
- Centre for Cancer Research and Cell Biology, Queen's University, Belfast, Northern Ireland, UK
| | - Elias Arkoudis
- Centre for Cancer Research and Cell Biology, Queen's University, Belfast, Northern Ireland, UK
| | - Anthony Dossang
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Caroline Hughes
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Eamon Cassidy
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Keeva McClelland
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Ewa Odrzywol
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Natalie Page
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Oliver Barker
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Hugues Miel
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK
| | - Timothy Harrison
- Almac Discovery Ltd, Centre for Precision Therapeutics, Belfast, Northern Ireland, UK.,Centre for Cancer Research and Cell Biology, Queen's University, Belfast, Northern Ireland, UK
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29
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Kim RQ, Sixma TK. Regulation of USP7: A High Incidence of E3 Complexes. J Mol Biol 2017; 429:3395-3408. [DOI: 10.1016/j.jmb.2017.05.028] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/26/2017] [Accepted: 05/30/2017] [Indexed: 01/03/2023]
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Piao S, Pei HZ, Huang B, Baek SH. Ovarian tumor domain-containing protein 1 deubiquitinates and stabilizes p53. Cell Signal 2017; 33:22-29. [DOI: 10.1016/j.cellsig.2017.02.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/10/2017] [Accepted: 02/10/2017] [Indexed: 12/22/2022]
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Mariggiò G, Koch S, Zhang G, Weidner-Glunde M, Rückert J, Kati S, Santag S, Schulz TF. Kaposi Sarcoma Herpesvirus (KSHV) Latency-Associated Nuclear Antigen (LANA) recruits components of the MRN (Mre11-Rad50-NBS1) repair complex to modulate an innate immune signaling pathway and viral latency. PLoS Pathog 2017; 13:e1006335. [PMID: 28430817 PMCID: PMC5415203 DOI: 10.1371/journal.ppat.1006335] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 05/03/2017] [Accepted: 04/05/2017] [Indexed: 12/31/2022] Open
Abstract
Kaposi Sarcoma Herpesvirus (KSHV), a γ2-herpesvirus and class 1 carcinogen, is responsible for at least three human malignancies: Kaposi Sarcoma (KS), Primary Effusion Lymphoma (PEL) and Multicentric Castleman's Disease (MCD). Its major nuclear latency protein, LANA, is indispensable for the maintenance and replication of latent viral DNA in infected cells. Although LANA is mainly a nuclear protein, cytoplasmic isoforms of LANA exist and can act as antagonists of the cytoplasmic DNA sensor, cGAS. Here, we show that cytosolic LANA also recruits members of the MRN (Mre11-Rad50-NBS1) repair complex in the cytosol and thereby inhibits their recently reported role in the sensing of cytoplasmic DNA and activation of the NF-κB pathway. Inhibition of NF-κB activation by cytoplasmic LANA is accompanied by increased lytic replication in KSHV-infected cells, suggesting that MRN-dependent NF-κB activation contributes to KSHV latency. Cytoplasmic LANA may therefore support the activation of KSHV lytic replication in part by counteracting the activation of NF-κB in response to cytoplasmic DNA. This would complement the recently described role of cytoplasmic LANA in blocking an interferon response triggered by cGAS and thereby promoting lytic reactivation. Our findings highlight a second point at which cytoplasmic LANA interferes with the innate immune response, as well as the importance of the recently discovered role of cytoplasmic MRN complex members as innate sensors of cytoplasmic DNA for the control of KSHV replication.
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MESH Headings
- Acid Anhydride Hydrolases
- Antigens, Viral/genetics
- Antigens, Viral/immunology
- Antigens, Viral/metabolism
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Cytoplasm/metabolism
- DNA Repair Enzymes/genetics
- DNA Repair Enzymes/metabolism
- DNA Replication
- DNA, Viral/genetics
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- HEK293 Cells
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/immunology
- Herpesvirus 8, Human/physiology
- Humans
- Immunity, Innate
- MRE11 Homologue Protein
- Models, Biological
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Nuclear Proteins/genetics
- Nuclear Proteins/immunology
- Nuclear Proteins/metabolism
- Protein Isoforms
- Sarcoma, Kaposi/immunology
- Sarcoma, Kaposi/virology
- Signal Transduction
- Virus Latency
- Virus Replication
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Affiliation(s)
- Giuseppe Mariggiò
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Sandra Koch
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Guigen Zhang
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Magdalena Weidner-Glunde
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Jessica Rückert
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Semra Kati
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Susann Santag
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
| | - Thomas F. Schulz
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research, Hannover-Braunschweig Site, Germany
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Jin WL, Mao XY, Qiu GZ. Targeting Deubiquitinating Enzymes in Glioblastoma Multiforme: Expectations and Challenges. Med Res Rev 2016; 37:627-661. [PMID: 27775833 DOI: 10.1002/med.21421] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/06/2016] [Accepted: 09/25/2016] [Indexed: 12/16/2022]
Abstract
Glioblastoma (GBM) is regarded as the most common primary intracranial neoplasm. Despite standard treatment with tumor resection and radiochemotherapy, the outcome remains gloomy. It is evident that a combination of oncogenic gain of function and tumor-suppressive loss of function has been attributed to glioma initiation and progression. The ubiquitin-proteasome system is a well-orchestrated system that controls the fate of most proteins by striking a dynamic balance between ubiquitination and deubiquitination of substrates, having a profound influence on the modulation of oncoproteins, tumor suppressors, and cellular signaling pathways. In recent years, deubiquitinating enzymes (DUBs) have emerged as potential anti-cancer targets due to their targeting several key proteins involved in the regulation of tumorigenesis, apoptosis, senescence, and autophagy. This review attempts to summarize recent studies of GBM-associated DUBs, their roles in various cellular processes, and discuss the relation between DUBs deregulation and gliomagenesis, especially how DUBs regulate glioma stem cells pluripotency, microenvironment, and resistance of radiation and chemotherapy through core stem-cell transcriptional factors. We also review recent achievements and progress in the development of potent and selective reversible inhibitors of DUBs, and attempted to find a potential GBM treatment by DUBs intervention.
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Affiliation(s)
- Wei-Lin Jin
- Institute of Nano Biomedicine and Engineering, Department of Instrument Science and Engineering, Key Laboratory for Thin Film and Microfabrication Technology of Ministry of Education, School of Electronic Information and Electronic Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.,National Centers for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - Xiao-Yuan Mao
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, P. R. China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, 410078, P. R. China
| | - Guan-Zhong Qiu
- Department of Neurosurgery, General Hospital of Jinan Military Command, Jinan, 250031, P. R. China
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Juillard F, Tan M, Li S, Kaye KM. Kaposi's Sarcoma Herpesvirus Genome Persistence. Front Microbiol 2016; 7:1149. [PMID: 27570517 PMCID: PMC4982378 DOI: 10.3389/fmicb.2016.01149] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/11/2016] [Indexed: 12/17/2022] Open
Abstract
Kaposi’s sarcoma-associated herpesvirus (KSHV) has an etiologic role in Kaposi’s sarcoma, primary effusion lymphoma, and multicentric Castleman’s disease. These diseases are most common in immunocompromised individuals, especially those with AIDS. Similar to all herpesviruses, KSHV infection is lifelong. KSHV infection in tumor cells is primarily latent, with only a small subset of cells undergoing lytic infection. During latency, the KSHV genome persists as a multiple copy, extrachromosomal episome in the nucleus. In order to persist in proliferating tumor cells, the viral genome replicates once per cell cycle and then segregates to daughter cell nuclei. KSHV only expresses several genes during latent infection. Prominent among these genes, is the latency-associated nuclear antigen (LANA). LANA is responsible for KSHV genome persistence and also exerts transcriptional regulatory effects. LANA mediates KSHV DNA replication and in addition, is responsible for segregation of replicated genomes to daughter nuclei. LANA serves as a molecular tether, bridging the viral genome to mitotic chromosomes to ensure that KSHV DNA reaches progeny nuclei. N-terminal LANA attaches to mitotic chromosomes by binding histones H2A/H2B at the surface of the nucleosome. C-terminal LANA binds specific KSHV DNA sequence and also has a role in chromosome attachment. In addition to the essential roles of N- and C-terminal LANA in genome persistence, internal LANA sequence is also critical for efficient episome maintenance. LANA’s role as an essential mediator of virus persistence makes it an attractive target for inhibition in order to prevent or treat KSHV infection and disease.
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Affiliation(s)
- Franceline Juillard
- Departments of Medicine, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Min Tan
- Departments of Medicine, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Shijun Li
- Departments of Medicine, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Kenneth M Kaye
- Departments of Medicine, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
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Ma M, Yu N. Ubiquitin-specific protease 7 expression is a prognostic factor in epithelial ovarian cancer and correlates with lymph node metastasis. Onco Targets Ther 2016; 9:1559-69. [PMID: 27051296 PMCID: PMC4803273 DOI: 10.2147/ott.s100050] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Objective Ubiquitin-specific protease 7 (USP7) is a common target of herpesviruses and is important in the DNA damage response, which is also upregulated in several cancers, including prostate, colon, liver, and lung cancers. However, less is known about its expression in ovarian cancer tissues. The role of USP7 in epithelial ovarian cancer (EOC) has not yet been investigated. Materials and methods We recruited 141 patients from Linyi People’s Hospital between June 1999 and June 2013, all pathologically diagnosed with primary EOC. Their clinical data were collected, and the expression of USP7 in the tumor tissues was determined using immunohistochemistry. The correlations between USP7 expression and the clinicopathological variables of patients with EOC were assessed using Spearman’s rank correlation test. Kaplan–Meier analysis and Cox regression analysis were used to identify the prognosis value of USP7. The function of USP7 in the EOC cells was also detected in vitro. Results Among the 141 cases, USP7 expression was high in 59 EOC samples (41.8%), and was significantly correlated with lymphatic invasion; USP7 can act as independent prognostic indicator for the overall survival (OS) of EOC, and its high expression was associated with poor OS rate. The RNA inteference and overexpression assays indicated that USP7 can positively regulate the ovarian cell vitality and invasion process. Conclusion Patients with EOC expressing high level of USP7 have worse OS compared with those with low USP7 expression. USP7 may be involved in the proliferation and invasion of EOC cells, and USP7 expression can serve as an independent predictor of EOC.
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Affiliation(s)
- Ming Ma
- Department of Oncology, Linyi People's Hospital, Linyi, People's Republic of China
| | - Nina Yu
- Department of Gynecology and Obstetrics, Linyi People's Hospital, Linyi, People's Republic of China
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35
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Chavoshi S, Egorova O, Lacdao IK, Farhadi S, Sheng Y, Saridakis V. Identification of Kaposi Sarcoma Herpesvirus (KSHV) vIRF1 Protein as a Novel Interaction Partner of Human Deubiquitinase USP7. J Biol Chem 2016; 291:6281-91. [PMID: 26786098 DOI: 10.1074/jbc.m115.710632] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Indexed: 12/25/2022] Open
Abstract
Viral interferon regulatory factor 1 (vIRF1), a Kaposi sarcoma herpesvirus protein, destabilizes p53 by inhibiting p53 acetylation and Hdm2 phosphorylation. This leads to increased ubiquitination and degradation of p53 by Hdm2, which cripples the cellular p53-mediated antiviral response. Ubiquitin-specific protease 7 (USP7) deubiquitinates p53 and Hdm2 and regulates their stability. We identified an EGPS consensus sequence in vIRF1, which is identical to that found in Epstein-Barr virus nuclear antigen 1 (EBNA1) that interacts with the N-terminal domain of USP7 (USP7-NTD). GST pulldown assays demonstrated that vIRF1 interacts with USP7-NTD via its EGPS motif. NMR heteronuclear single quantum correlation (HSQC) analysis revealed chemical perturbations after titration of USP7-NTD with vIRF1 (44)SPGEGPSGTG(53) peptide. In contrast, these perturbations were reduced with a mutant vIRF1 peptide, (44)SPGEGPAGTG(53). Fluorescence polarization analysis indicated that the vIRF1 peptide interacted with USP7-NTD with a Kd of 2.0 μm. The crystal structure of the USP7-NTD·vIRF1 peptide complex revealed an identical mode of binding as that of the EBNA1 peptide to USP7-NTD. We also showed that USP7 interacts with vIRF1 in U2OS cells. Decreased levels of p53, but not Hdm2 or ataxia telangiectasia-mutated (ATM), were seen after expression of vIRF1, but not with a vIRF1 mutant protein. Our results support a new role for vIRF1 through deregulation of the deubiquitinating enzyme USP7 to inhibit p53-mediated antiviral responses.
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Affiliation(s)
- Sara Chavoshi
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Olga Egorova
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Ira Kay Lacdao
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Sahar Farhadi
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Yi Sheng
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Vivian Saridakis
- From the Department of Biology, York University, Toronto, Ontario M3J 1P3, Canada
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36
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Li S, Tan M, Juillard F, Ponnusamy R, Correia B, Simas JP, Carrondo MA, McVey CE, Kaye KM. The Kaposi Sarcoma Herpesvirus Latency-associated Nuclear Antigen DNA Binding Domain Dorsal Positive Electrostatic Patch Facilitates DNA Replication and Episome Persistence. J Biol Chem 2015; 290:28084-28096. [PMID: 26420481 DOI: 10.1074/jbc.m115.674622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Indexed: 12/15/2022] Open
Abstract
Kaposi sarcoma-associated herpesvirus (KSHV) has a causative role in several human malignancies. KSHV latency-associated nuclear antigen (LANA) mediates persistence of viral episomes in latently infected cells. LANA mediates KSHV DNA replication and segregates episomes to progeny nuclei. The structure of the LANA DNA binding domain was recently solved, revealing a positive electrostatic patch opposite the DNA binding surface, which is the site of BET protein binding. Here we investigate the functional role of the positive patch in LANA-mediated episome persistence. As expected, LANA mutants with alanine or glutamate substitutions in the central, peripheral, or lateral portions of the positive patch maintained the ability to bind DNA by EMSA. However, all of the substitution mutants were deficient for LANA DNA replication and episome maintenance. Mutation of the peripheral region generated the largest deficiencies. Despite these deficiencies, all positive patch mutants concentrated to dots along mitotic chromosomes in cells containing episomes, similar to LANA. The central and peripheral mutants, but not the lateral mutants, were reduced for BET protein interaction as assessed by co-immunoprecipitation. However, defects in BET protein binding were independent of episome maintenance function. Overall, the reductions in episome maintenance closely correlated with DNA replication deficiencies, suggesting that the replication defects account for the reduced episome persistence. Therefore, the electrostatic patch exerts a key role in LANA-mediated DNA replication and episome persistence and may act through a host cell partner(s) other than a BET protein or by inducing specific structures or complexes.
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Affiliation(s)
- Shijun Li
- Departments of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, 02115
| | - Min Tan
- Departments of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, 02115
| | - Franceline Juillard
- Departments of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, 02115
| | - Rajesh Ponnusamy
- Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
| | - Bruno Correia
- Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
| | - J Pedro Simas
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Maria A Carrondo
- Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
| | - Colin E McVey
- Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, 2781-901 Oeiras, Portugal
| | - Kenneth M Kaye
- Departments of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, 02115.
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Pozhidaeva AK, Mohni KN, Dhe-Paganon S, Arrowsmith CH, Weller SK, Korzhnev DM, Bezsonova I. Structural Characterization of Interaction between Human Ubiquitin-specific Protease 7 and Immediate-Early Protein ICP0 of Herpes Simplex Virus-1. J Biol Chem 2015. [PMID: 26224631 DOI: 10.1074/jbc.m115.664805] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Human ubiquitin-specific protease 7 (USP7) is a deubiquitinating enzyme that prevents protein degradation by removing polyubiquitin chains from its substrates. It regulates the stability of a number of human transcription factors and tumor suppressors and plays a critical role in the development of several types of cancer, including prostate and small cell lung cancer. In addition, human USP7 is targeted by several viruses of the Herpesviridae family and is required for effective herpesvirus infection. The USP7 C-terminal region (C-USP7) contains five ubiquitin-like domains (UBL1-5) that interact with several USP7 substrates. Although structures of the USP7 C terminus bound to its substrates could provide vital information for understanding USP7 substrate specificity, no such data has been available to date. In this work we have demonstrated that the USP7 ubiquitin-like domains can be studied in isolation by solution NMR spectroscopy, and we have determined the structure of the UBL1 domain. Furthermore, we have employed NMR and viral plaque assays to probe the interaction between the C-USP7 and HSV-1 immediate-early protein ICP0 (infected cell protein 0), which is essential for efficient lytic infection and virus reactivation from latency. We have shown that depletion of the USP7 in HFF-1 cells negatively affects the efficiency of HSV-1 lytic infection. We have also found that USP7 directly binds ICP0 via its C-terminal UBL1-2 domains and mapped the USP7-binding site for ICP0. Therefore, this study represents a first step toward understanding the molecular mechanism of C-USP7 specificity toward its substrates and may provide the basis for future development of novel antiviral and anticancer therapies.
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Affiliation(s)
- Alexandra K Pozhidaeva
- From the Department of Molecular Biology and Biophysics, University of Connecticut Health, Farmington, Connecticut 06030
| | - Kareem N Mohni
- the Department of Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Sirano Dhe-Paganon
- the Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215, and
| | - Cheryl H Arrowsmith
- the Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Sandra K Weller
- From the Department of Molecular Biology and Biophysics, University of Connecticut Health, Farmington, Connecticut 06030
| | - Dmitry M Korzhnev
- From the Department of Molecular Biology and Biophysics, University of Connecticut Health, Farmington, Connecticut 06030
| | - Irina Bezsonova
- From the Department of Molecular Biology and Biophysics, University of Connecticut Health, Farmington, Connecticut 06030,
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Giovinazzi S, Sirleto P, Aksenova V, Morozov VM, Zori R, Reinhold WC, Ishov AM. Usp7 protects genomic stability by regulating Bub3. Oncotarget 2015; 5:3728-42. [PMID: 25003721 PMCID: PMC4116516 DOI: 10.18632/oncotarget.1989] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
USP7 (Ubiquitin Specific processing Protease-7) is a deubiquitinase which, over the past decade emerged as a critical regulator of cellular processes. Deregulation of USP7 activity has been linked to cancer, making USP7 inhibition an appealing anti-cancer strategy. The identification of novel USP7 substrates and additional USP7-dependent cellular activities will broaden our knowledge towards potential clinical application of USP7 inhibitors. Results presented in this study uncover a novel and pivotal function of USP7 in the maintenance of genomic stability. Upon USP7 depletion we observed prolonged mitosis and mitotic abnormalities including micronuclei accumulation, lagging chromosomes and karyotype instability. Inhibition of USP7 with small molecule inhibitors stabilizes cyclin B and causes mitotic abnormalities. Our results suggest that these USP7-dependent effects are mediated by decreased levels of spindle assembly checkpoint (SAC) component Bub3, which we characterized as an interacting partner and substrate of USP7. In silico analysis across the NCI-60 panels of cell lines supports our results where lower levels of USP7 strongly correlate with genomic instability. In conclusion, we identified a novel role of USP7 as regulator of the SAC component Bub3 and genomic stability.
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Affiliation(s)
- Serena Giovinazzi
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL; University of Florida Health Cancer Center, Gainesville, FL
| | | | | | | | | | | | - Alexander M Ishov
- Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL; University of Florida Health Cancer Center, Gainesville, FL
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A survey of the interactome of Kaposi's sarcoma-associated herpesvirus ORF45 revealed its binding to viral ORF33 and cellular USP7, resulting in stabilization of ORF33 that is required for production of progeny viruses. J Virol 2015; 89:4918-31. [PMID: 25694600 DOI: 10.1128/jvi.02925-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 02/10/2015] [Indexed: 01/05/2023] Open
Abstract
UNLABELLED The ORF45 protein of Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus-specific immediate-early tegument protein. Our previous studies have revealed its crucial roles in both early and late stages of KSHV infection. In this study, we surveyed the interactome of ORF45 using a panel of monoclonal antibodies. In addition to the previously identified extracellular regulated kinase (ERK) and p90 ribosomal S6 kinase (RSK) proteins, we found several other copurified proteins, including prominent ones of ∼38 kDa and ∼130 kDa. Mass spectrometry revealed that the 38-kDa protein is viral ORF33 and the 130-kDa protein is cellular USP7 (ubiquitin-specific protease 7). We mapped the ORF33-binding domain to the highly conserved carboxyl-terminal 19 amino acids (aa) of ORF45 and the USP7-binding domain to the reported consensus motif in the central region of ORF45. Using immunofluorescence staining, we observed colocalization of ORF45 with ORF33 or USP7 both under transfected conditions and in KSHV-infected cells. Moreover, we noticed ORF45-dependent relocalization of a portion of ORF33/USP7 from the nucleus to the cytoplasm. We found that ORF45 caused an increase in ORF33 protein accumulation that was abolished if either the ORF33- or USP7-binding domain in ORF45 was deleted. Furthermore, deletion of the conserved carboxyl terminus of ORF45 in the KSHV genome drastically reduced the level of ORF33 protein in KSHV-infected cells and abolished production of progeny virions. Collectively, our results not only reveal new components of the ORF45 interactome, but also demonstrate that the interactions among these proteins are crucial for KSHV lytic replication. IMPORTANCE Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of several human cancers. KSHV ORF45 is a multifunctional protein that is required for KSHV lytic replication, but the exact mechanisms by which ORF45 performs its critical functions are unclear. Our previous studies revealed that all ORF45 protein in cells exists in high-molecular-weight complexes. We therefore sought to characterize the interactome of ORF45 to provide insights into its roles during lytic replication. Using a panel of monoclonal antibodies, we surveyed the ORF45 interactome in KSHV-infected cells. We identified two new binding partners of ORF45: the viral protein ORF33 and cellular ubiquitin-specific protease 7 (USP7). We further demonstrate that the interaction between ORF45 and ORF33 is crucial for the efficient production of KSHV viral particles, suggesting that the targeted interference with this interaction may represent a novel strategy to inhibit KSHV lytic replication.
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40
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Abstract
Deubiquitinases (DUBs) play important roles and therefore are potential drug targets in various diseases including cancer and neurodegeneration. In this review, we recapitulate structure-function studies of the most studied DUBs including USP7, USP22, CYLD, UCHL1, BAP1, A20, as well as ataxin 3 and connect them to regulatory mechanisms and their growing protein interaction networks. We then describe DUBs that have been associated with endocrine carcinogenesis with a focus on prostate, ovarian, and thyroid cancer, pheochromocytoma, and adrenocortical carcinoma. The goal is enhancing our understanding of the connection between dysregulated DUBs and cancer to permit the design of therapeutics and to establish biomarkers that could be used in diagnosis and prognosis.
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Affiliation(s)
- Roland Pfoh
- Department of BiologyYork University, 4700 Keele Street, Toronto, Ontario, Canada, M3J1P3
| | - Ira Kay Lacdao
- Department of BiologyYork University, 4700 Keele Street, Toronto, Ontario, Canada, M3J1P3
| | - Vivian Saridakis
- Department of BiologyYork University, 4700 Keele Street, Toronto, Ontario, Canada, M3J1P3
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Abstract
Epstein-Barr nuclear antigen 1 (EBNA1) plays multiple important roles in EBV latent infection and has also been shown to impact EBV lytic infection. EBNA1 is required for the stable persistence of the EBV genomes in latent infection and activates the expression of other EBV latency genes through interactions with specific DNA sequences in the viral episomes. EBNA1 also interacts with several cellular proteins to modulate the activities of multiple cellular pathways important for viral persistence and cell survival. These cellular effects are also implicated in oncogenesis, suggesting a direct role of EBNA1 in the development of EBV-associated tumors.
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Affiliation(s)
- Lori Frappier
- Department of Molecular Genetics, University of Toronto, 1 Kings College Circle, Toronto, ON, M5S 1A8, Canada.
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42
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De León Vázquez E, Juillard F, Rosner B, Kaye KM. A short sequence immediately upstream of the internal repeat elements is critical for KSHV LANA mediated DNA replication and impacts episome persistence. Virology 2013; 448:344-55. [PMID: 24314665 DOI: 10.1016/j.virol.2013.10.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 08/12/2013] [Accepted: 10/18/2013] [Indexed: 02/06/2023]
Abstract
Kaposi's sarcoma-associated herpesvirus LANA (1162 residues) mediates episomal persistence of viral genomes during latency. LANA mediates viral DNA replication and segregates episomes to daughter nuclei. A 59 residue deletion immediately upstream of the internal repeat elements rendered LANA highly deficient for DNA replication and modestly deficient for the ability to segregate episomes, while smaller deletions did not. The 59 amino acid deletion reduced LANA episome persistence by ~14-fold, while sequentially smaller deletions resulted in ~3-fold, or no deficiency. Three distinct LANA regions reorganized heterochromatin, one of which contains the deleted sequence, but the deletion did not abolish LANA's ability to alter chromatin. Therefore, this work identifies a short internal LANA sequence that is critical for DNA replication, has modest effects on episome segregation, and substantially impacts episome persistence; this region may exert its effects through an interacting host cell protein(s).
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Affiliation(s)
- Erika De León Vázquez
- Departments of Medicine, Brigham and Women's Hospital and Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, United States
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43
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Abstract
The minichromosome maintenance (MCM) complex, which plays multiple important roles in DNA replication, is loaded onto chromatin following mitosis, remains on chromatin until the completion of DNA synthesis, and then is unloaded by a poorly defined mechanism that involves the MCM binding protein (MCM-BP). Here we show that MCM-BP directly interacts with the ubiquitin-specific protease USP7, that this interaction occurs predominantly on chromatin, and that MCM-BP can tether USP7 to MCM proteins. Detailed biochemical and structure analyses of the USP7-MCM-BP interaction showed that the (155)PSTS(158) MCM-BP sequence mediates critical interactions with the TRAF domain binding pocket of USP7. Analysis of the effects of USP7 knockout on DNA replication revealed that lack of USP7 results in slowed progression through late S phase without globally affecting the fork rate or origin usage. Lack of USP7 also resulted in increased levels of MCM proteins on chromatin, and investigation of the cause of this increase revealed a defect in the dissociation of MCM proteins from chromatin in mid- to late S phase. This role of USP7 mirrors the previously described role for MCM-BP in MCM complex unloading and suggests that USP7 works with MCM-BP to unload MCM complexes from chromatin at the end of S phase.
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44
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Nanduri B, Suvarnapunya AE, Venkatesan M, Edelmann MJ. Deubiquitinating enzymes as promising drug targets for infectious diseases. Curr Pharm Des 2013; 19:3234-47. [PMID: 23151130 DOI: 10.2174/1381612811319180008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 11/01/2012] [Indexed: 01/25/2023]
Abstract
Deubiquitinating enzymes (DUBs) remove ubiquitin and ubiquitin-like modifications from proteins and they have been known to contribute to processes relevant in microbial infection, such as immune responses pathways. Numerous viral and bacterial DUBs have been identified, and activities of several host DUBs are known to be modulated during the infection process, either by a pathogen or by a host. Recently there have been attempts to take advantage of this feature and design therapeutic inhibitors of DUBs that can be used to limit the spread of infection. This review is focused on exploring the potential of DUBs in the treatment of infectious diseases.
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Affiliation(s)
- Bindu Nanduri
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
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45
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Domsic JF, Chen HS, Lu F, Marmorstein R, Lieberman PM. Molecular basis for oligomeric-DNA binding and episome maintenance by KSHV LANA. PLoS Pathog 2013; 9:e1003672. [PMID: 24146617 PMCID: PMC3798644 DOI: 10.1371/journal.ppat.1003672] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 08/16/2013] [Indexed: 12/20/2022] Open
Abstract
LANA is the KSHV-encoded terminal repeat binding protein essential for viral replication and episome maintenance during latency. We have determined the X-ray crystal structure of LANA C-terminal DNA binding domain (LANADBD) to reveal its capacity to form a decameric ring with an exterior DNA binding surface. The dimeric core is structurally similar to EBV EBNA1 with an N-terminal arm that regulates DNA binding and is required for replication function. The oligomeric interface between LANA dimers is dispensable for single site DNA binding, but is required for cooperative DNA binding, replication function, and episome maintenance. We also identify a basic patch opposite of the DNA binding surface that is responsible for the interaction with BRD proteins and contributes to episome maintenance function. The structural features of LANADBD suggest a novel mechanism of episome maintenance through DNA-binding induced oligomeric assembly. Kaposi's sarcoma-associated herpesvirus (KSHV) establishes latent infections that are associated with several cancers including Kaposi's sarcoma, pleural effusion lymphoma, and multicentric Caslteman's disease. One of the major viral proteins required for establishment and maintenance of the latent state is the latency-associated nuclear antigen (LANA). LANA binds to DNA sequences within the terminal repeats (TR) of the viral genome and stimulates both DNA replication and episome maintenance during latency. Here we present the X-ray crystal structure of the DNA binding domain of LANA (LANADBD) and show that it has the capacity to form oligomeric complexes upon DNA binding. We characterize structural features of LANADBD that are required for oligomerization, DNA binding, and interaction with host cell BET proteins, BRD2 and BRD4, which are important for mediating multiple functions of LANA, including episome maintenance.
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MESH Headings
- Antigens, Viral/chemistry
- Antigens, Viral/genetics
- Antigens, Viral/metabolism
- Cell Line, Tumor
- DNA Replication
- DNA, Viral/chemistry
- DNA, Viral/genetics
- DNA, Viral/metabolism
- Herpesvirus 8, Human/chemistry
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/metabolism
- Humans
- Nuclear Proteins/chemistry
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Plasmids/chemistry
- Plasmids/genetics
- Plasmids/metabolism
- Protein Binding
- Protein Multimerization
- Protein Structure, Quaternary
- Protein Structure, Tertiary
- Structure-Activity Relationship
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Affiliation(s)
- John F. Domsic
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Horng-Shen Chen
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Fang Lu
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
| | - Ronen Marmorstein
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
- * E-mail: (RM); (PML)
| | - Paul M. Lieberman
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania, United States of America
- * E-mail: (RM); (PML)
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46
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Identification of Kaposi's sarcoma-associated herpesvirus LANA regions important for episome segregation, replication, and persistence. J Virol 2013; 87:12270-83. [PMID: 24006437 DOI: 10.1128/jvi.01243-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) is a 1,162-amino-acid protein that mediates the maintenance of episomal viral genomes in latently infected cells. The two central components of episome persistence are DNA replication with each cell division and the segregation of DNA to progeny nuclei. LANA self-associates to bind KSHV terminal-repeat (TR) DNA and to mediate its replication. LANA also simultaneously binds to TR DNA and mitotic chromosomes to mediate the segregation of episomes to daughter nuclei. The N-terminal region of LANA binds histones H2A and H2B to attach to mitotic chromosomes, while the C-terminal region binds TR DNA and also associates with chromosomes. Both the N- and C-terminal regions of LANA are essential for episome persistence. We recently showed that deletion of all internal LANA sequences results in highly deficient episome maintenance. Here we assess independent internal LANA regions for effects on episome persistence. We generated a panel of LANA mutants that included deletions in the large internal repeat region and in the unique internal sequence. All mutants contained the essential N- and C-terminal regions, and as expected, all maintained the ability to associate with mitotic chromosomes in a wild-type fashion and to bind TR DNA, as assessed by electrophoretic mobility shift assays (EMSA). Deletion of the internal regions did not reduce the half-life of LANA. Notably, deletions within either the repeat elements or the unique sequence resulted in deficiencies in DNA replication. However, only the unique internal sequence exerted effects on the ability of LANA to retain green fluorescent protein (GFP) expression from TR-containing episomes deficient in DNA replication, consistent with a role in episome segregation; this region did not independently associate with mitotic chromosomes. All mutants were deficient in episome persistence, and the deficiencies ranged from minor to severe. Mutants deficient in DNA replication that contained deletions within the unique internal sequence had the most-severe deficits. These data suggest that internal LANA regions exert critical roles in LANA-mediated DNA replication, segregation, and episome persistence, likely through interactions with key host cell factors.
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47
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Cha S, Seo T. Viral genome maintenance and latent replication of human gammaherpesviruses. Future Virol 2013. [DOI: 10.2217/fvl.13.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
During gammaherpesvirus latency, only a few genes are expressed and required for maintenance of viral latency over a long period. While the expressed latent viral proteins play functional roles in viral latent DNA replication, they do not have replication-associated enzymatic activity such as polymerase or helicase activity. Viral genomes are detected in a similar copy number per infected cell, suggesting that the viral genome is replicated and segregated using host replication machinery. Kaposi’s sarcoma-associated herpesvirus and EBV have trans-acting elements required for viral genome maintenance during latency; LANA1 and EBNA1, respectively. The proteins recruit host replication-associated proteins at their latent origins, leading to initiation of viral replication and segregation with host chromosomes once per cell cycle. In addition, viral latent origins (cis-elements) provide trans-element-binding sites as well as a sufficient space for recruitment of cellular factors. In this review, we describe the molecular mechanisms required for replication of the viral genome during latency, including interactions with cellular factors and the interplay between viral trans- and cis-elements.
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Affiliation(s)
- Seho Cha
- Department of Life Science, Dongguk University-Seoul, 26, 3 Pil-dong, Jung-gu, Seoul, 100-715, Republic of Korea
| | - Taegun Seo
- Department of Life Science, Dongguk University-Seoul, 26, 3 Pil-dong, Jung-gu, Seoul, 100-715, Republic of Korea.
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48
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Epigenetic regulation of EBV and KSHV latency. Curr Opin Virol 2013; 3:251-9. [PMID: 23601957 DOI: 10.1016/j.coviro.2013.03.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 03/07/2013] [Accepted: 03/13/2013] [Indexed: 12/25/2022]
Abstract
The gammaherpesviruses are unique for their capacity to establish a variety of gene expression programs during latent and lytic infection. This capacity enables the virus to control host-cell proliferation, prevent programmed cell death, elude immune cell detection, and ultimately adapt to a wide range of environmental and developmental changes in the host cell. This remarkable plasticity of gene expression results from the combined functionalities of viral and host factors that biochemically remodel and epigenetically modify the viral chromosome. These epigenetic modifications range from primary DNA methylations, to chromatin protein post-translational modifications, to higher-order chromosome conformations. In addition, gammaherpesviruses have acquired specialized tools to modulate the epigenetic processes that promote viral genome propagation and host-cell survival.
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49
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Ching W, Koyuncu E, Singh S, Arbelo-Roman C, Hartl B, Kremmer E, Speiseder T, Meier C, Dobner T. A ubiquitin-specific protease possesses a decisive role for adenovirus replication and oncogene-mediated transformation. PLoS Pathog 2013; 9:e1003273. [PMID: 23555268 PMCID: PMC3610741 DOI: 10.1371/journal.ppat.1003273] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 02/11/2013] [Indexed: 11/17/2022] Open
Abstract
Adenoviral replication depends on viral as well as cellular proteins. However, little is known about cellular proteins promoting adenoviral replication. In our screens to identify such proteins, we discovered a cellular component of the ubiquitin proteasome pathway interacting with the central regulator of adenoviral replication. Our binding assays mapped a specific interaction between the N-terminal domains of both viral E1B-55K and USP7, a deubiquitinating enzyme. RNA interference-mediated downregulation of USP7 severely reduced E1B-55K protein levels, but more importantly negatively affected adenoviral replication. We also succeeded in resynthesizing an inhibitor of USP7, which like the knockdown background reduced adenoviral replication. Further assays revealed that not only adenoviral growth, but also adenoviral oncogene-driven cellular transformation relies on the functions of USP7. Our data provide insights into an intricate mechanistic pathway usurped by an adenovirus to promote its replication and oncogenic functions, and at the same time open up possibilities for new antiviral strategies. Adenoviral infections can result in severe outcomes leading to mortality especially in children undergoing immunosuppressive therapies. Unfortunately, no specific anti-adenoviral treatments are available to treat disseminated adenoviral infections. We have set out to identify host factors promoting adenoviral growth and could identify the cellular protein Ubiquitin-specific protease 7 (USP7) being central to adenoviral infection. Here we show that USP7 interacts with the viral protein E1B-55K, a central regulator of adenoviral replication and adenoviral oncogene-mediated cellular transformation. We demonstrate that USP7 ensures stability and/or proper expression levels of adenoviral proteins at early and late time points of infection. Consistent with this, small-molecule inhibitors of USP7 showed efficient reduction of capsid protein levels and viral progeny numbers. Thus, USP7 inhibition might be a useful treatment option in the context of disseminated adenoviral infections. Moreover, we were also able to show that adenoviral oncogene-mediated cellular transformation can be hampered by USP7 disruption. In summary, this study shows that two different adenoviral disease mechanisms can be inhibited by targeting one host cellular factor.
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Affiliation(s)
- Wilhelm Ching
- Department of Molecular Virology, Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
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50
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Overexpression of the ubiquitin-specific protease 7 resulting from transfection or mutations in the ICP0 binding site accelerates rather than depresses herpes simplex virus 1 gene expression. J Virol 2012; 86:12871-8. [PMID: 22993145 DOI: 10.1128/jvi.01981-12] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Earlier studies reported that ICP0, a key regulatory protein encoded by herpes simplex virus 1 (HSV-1), binds ubiquitin-specific protease 7 (USP7). The fundamental conclusion of these studies is that depletion of USP7 destabilized ICP0, that ICP0 mediated the degradation of USP7, and that amino acid substitutions in ICP0 that abolished binding to USP7 significantly impaired the ability of HSV-1 to replicate. We show here that, indeed, depletion of USP7 leads to reduction of ICP0 and that USP7 is degraded in an ICP0-dependent manner. However, overexpression of USP7 or substitution in ICP0 of a single amino acid to abolish binding to USP7 accelerated the accumulation of viral mRNAs and proteins at early times after infection and had no deleterious effect on virus yields. A clue as to why USP7 is degraded emerged from the observation that, notwithstanding the accelerated expression of viral genes, the plaques formed by the mutant virus were very small, implying a defect in virus transmission from cell to cell.
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