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Dobransky A, Root M, Hafner N, Marcum M, Sharifi HJ. CRL4-DCAF1 Ubiquitin Ligase Dependent Functions of HIV Viral Protein R and Viral Protein X. Viruses 2024; 16:1313. [PMID: 39205287 PMCID: PMC11360348 DOI: 10.3390/v16081313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2024] [Revised: 08/04/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
The Human Immunodeficiency Virus (HIV) encodes several proteins that contort the host cell environment to promote viral replication and spread. This is often accomplished through the hijacking of cellular ubiquitin ligases. These reprogrammed complexes initiate or enhance the ubiquitination of cellular proteins that may otherwise act to restrain viral replication. Ubiquitination of target proteins may alter protein function or initiate proteasome-dependent destruction. HIV Viral Protein R (Vpr) and the related HIV-2 Viral Protein X (Vpx), engage the CRL4-DCAF1 ubiquitin ligase complex to target numerous cellular proteins. In this review we describe the CRL4-DCAF1 ubiquitin ligase complex and its interactions with HIV Vpr and Vpx. We additionally summarize the cellular proteins targeted by this association as well as the observed or hypothesized impact on HIV.
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Affiliation(s)
- Ashley Dobransky
- Department of Biological and Environmental Sciences, Le Moyne College, Syracuse, NY 13214, USA
| | - Mary Root
- Department of Biological and Environmental Sciences, Le Moyne College, Syracuse, NY 13214, USA
| | - Nicholas Hafner
- Department of Biological and Environmental Sciences, Le Moyne College, Syracuse, NY 13214, USA
| | - Matty Marcum
- Department of Biological and Environmental Sciences, Le Moyne College, Syracuse, NY 13214, USA
| | - H John Sharifi
- Department of Biological and Environmental Sciences, Le Moyne College, Syracuse, NY 13214, USA
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Sharifi HJ, Paine DN, Fazzari VA, Tipple AF, Patterson E, de Noronha CMC. Sulforaphane Reduces SAMHD1 Phosphorylation To Protect Macrophages from HIV-1 Infection. J Virol 2022; 96:e0118722. [PMID: 36377871 PMCID: PMC9749475 DOI: 10.1128/jvi.01187-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 10/24/2022] [Indexed: 11/16/2022] Open
Abstract
The cellular protein SAMHD1 is important for DNA repair, suppressing LINE elements, controlling deoxynucleoside triphosphate (dNTP) concentrations, maintaining HIV-1 latency, and preventing excessive type I interferon responses. SAMHD1 is also a potent inhibitor of HIV-1 and other significant viral pathogens. Infection restriction is due in part to the deoxynucleoside triphosphatase (dNTPase) activity of SAMHD1 but is also mediated through a dNTPase-independent mechanism that has been described but not explored. The phosphorylation of SAMHD1 at threonine 592 (T592) controls many of its functions. Retroviral restriction, irrespective of dNTPase activity, is linked to unphosphorylated T592. Sulforaphane (SFN), an isothiocyanate, protects macrophages from HIV infection by mobilizing the transcription factor and antioxidant response regulator Nrf2. Here, we show that SFN and other clinically relevant Nrf2 mobilizers reduce SAMHD1 T592 phosphorylation to protect macrophages from HIV-1. We further show that SFN, through Nrf2, triggers the upregulation of the cell cycle control protein p21 in human monocyte-derived macrophages to contribute to SAMHD1 activation. We additionally present data that support another, potentially redox-dependent mechanism employed by SFN to contribute to SAMHD1 activation through reduced phosphorylation. This work establishes the use of exogenous Nrf2 mobilizers as a novel way to study virus restriction by SAMHD1 and highlights the Nrf2 pathway as a potential target for the therapeutic control of SAMHD1 cellular and antiviral functions. IMPORTANCE Here, we show, for the first time, that the treatment of macrophages with Nrf2 mobilizers, known activators of antioxidant responses, increases the fraction of SAMHD1 without a regulatory phosphate at position 592. We demonstrate that this decreases infection of macrophages by HIV-1. Phosphorylated SAMHD1 is important for DNA repair, the suppression of LINE elements, the maintenance of HIV-1 in a latent state, and the prevention of excessive type I interferon responses, while unphosphorylated SAMHD1 blocks HIV infection. SAMHD1 impacts many viruses and is involved in various cancers, so knowledge of how it works and how it is regulated has broad implications for the development of therapeutics. Redox-modulating therapeutics are already in clinical use or under investigation for the treatment of many conditions. Thus, understanding the impact of redox modifiers on controlling SAMHD1 phosphorylation is important for many areas of research in microbiology and beyond.
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Affiliation(s)
- H. John Sharifi
- Albany College of Pharmacy and Health Sciences, Albany, New York, USA
| | - Dakota N. Paine
- Albany College of Pharmacy and Health Sciences, Albany, New York, USA
| | | | | | - Emilee Patterson
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, New York, USA
| | - Carlos M. C. de Noronha
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, New York, USA
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Shan H, Wang B, Zhang X, Song H, Li X, Zou Y, Jiang B, Hu H, Dou H, Shao C, Gao L, Ma C, Yang X, Liang X, Gong Y. CUL4B facilitates HBV replication by promoting HBx stabilization. Cancer Biol Med 2021; 19:j.issn.2095-3941.2020.0468. [PMID: 33969670 PMCID: PMC8763003 DOI: 10.20892/j.issn.2095-3941.2020.0468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 12/24/2020] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVE Hepatitis B virus (HBV) infection is a major public health problem worldwide. However, the regulatory mechanisms underlying HBV replication remain unclear. Cullin 4B-RING ubiquitin E3 ligase (CRL4B) is involved in regulating diverse physiological and pathophysiological processes. In our study, we aimed to explain the role of CUL4B in HBV infection. METHODS Cul4b transgenic mice or conditional knockout mice, as well as liver cell lines with CUL4B overexpression or knockdown, were used to assess the role of CUL4B in HBV replication. Immunoprecipitation assays and immunofluorescence staining were performed to study the interaction between CUL4B and HBx. Cycloheximide chase assays and in vivo ubiquitination assays were performed to evaluate the half-life and the ubiquitination status of HBx. RESULTS The hydrodynamics-based hepatitis B model in Cul4b transgenic or conditional knockout mice indicated that CUL4B promoted HBV replication (P < 0.05). Moreover, the overexpression or knockdown system in human liver cell lines validated that CUL4B increased HBV replication in an HBx-dependent manner. Importantly, immunoprecipitation assays and immunofluorescence staining showed an interaction between CUL4B and HBx. Furthermore, CUL4B upregulated HBx protein levels by inhibiting HBx ubiquitination and proteasomal degradation (P < 0.05). Finally, a positive correlation between CUL4B expression and HBV pgRNA level was observed in liver tissues from HBV-positive patients and HBV transgenic mice. CONCLUSIONS CUL4B enhances HBV replication by interacting with HBx and disrupting its ubiquitin-dependent proteasomal degradation. CUL4B may therefore be a potential target for anti-HBV therapy.
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Affiliation(s)
- Haixia Shan
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
- Department of Laboratory Diagnosis, Cangzhou Combination of Traditional Chinese and Western Medicine Hospital of Hebei Province, Cangzhou 061000, China
| | - Bo Wang
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai 200120, China
| | - Xiaodong Zhang
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Hui Song
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Xi Li
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Yongxin Zou
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Baichun Jiang
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Huili Hu
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Hao Dou
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Changshun Shao
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
| | - Lifen Gao
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
- Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, Jinan 250012, China
| | - Chunhong Ma
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
- Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, Jinan 250012, China
| | - Xiaoyun Yang
- Department of Gastroenterology, Qilu Hospital, Shandong University, Jinan 250012, China
| | - Xiaohong Liang
- Key Laboratory for Experimental Teratology of the Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
- Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, Jinan 250012, China
| | - Yaoqin Gong
- Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan 250012, China
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SAMHD1 Functions and Human Diseases. Viruses 2020; 12:v12040382. [PMID: 32244340 PMCID: PMC7232136 DOI: 10.3390/v12040382] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 12/12/2022] Open
Abstract
Deoxynucleoside triphosphate (dNTP) molecules are essential for the replication and maintenance of genomic information in both cells and a variety of viral pathogens. While the process of dNTP biosynthesis by cellular enzymes, such as ribonucleotide reductase (RNR) and thymidine kinase (TK), has been extensively investigated, a negative regulatory mechanism of dNTP pools was recently found to involve sterile alpha motif (SAM) domain and histidine-aspartate (HD) domain-containing protein 1, SAMHD1. When active, dNTP triphosphohydrolase activity of SAMHD1 degrades dNTPs into their 2'-deoxynucleoside (dN) and triphosphate subparts, steadily depleting intercellular dNTP pools. The differential expression levels and activation states of SAMHD1 in various cell types contributes to unique dNTP pools that either aid (i.e., dividing T cells) or restrict (i.e., nondividing macrophages) viral replication that consumes cellular dNTPs. Genetic mutations in SAMHD1 induce a rare inflammatory encephalopathy called Aicardi-Goutières syndrome (AGS), which phenotypically resembles viral infection. Recent publications have identified diverse roles for SAMHD1 in double-stranded break repair, genome stability, and the replication stress response through interferon signaling. Finally, a series of SAMHD1 mutations were also reported in various cancer cell types while why SAMHD1 is mutated in these cancer cells remains to investigated. Here, we reviewed a series of studies that have begun illuminating the highly diverse roles of SAMHD1 in virology, immunology, and cancer biology.
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Cheng J, Guo J, North BJ, Tao K, Zhou P, Wei W. The emerging role for Cullin 4 family of E3 ligases in tumorigenesis. Biochim Biophys Acta Rev Cancer 2018; 1871:138-159. [PMID: 30602127 DOI: 10.1016/j.bbcan.2018.11.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 11/28/2018] [Accepted: 11/29/2018] [Indexed: 02/06/2023]
Abstract
As a member of the Cullin-RING ligase family, Cullin-RING ligase 4 (CRL4) has drawn much attention due to its broad regulatory roles under physiological and pathological conditions, especially in neoplastic events. Based on evidence from knockout and transgenic mouse models, human clinical data, and biochemical interactions, we summarize the distinct roles of the CRL4 E3 ligase complexes in tumorigenesis, which appears to be tissue- and context-dependent. Notably, targeting CRL4 has recently emerged as a noval anti-cancer strategy, including thalidomide and its derivatives that bind to the substrate recognition receptor cereblon (CRBN), and anticancer sulfonamides that target DCAF15 to suppress the neoplastic proliferation of multiple myeloma and colorectal cancers, respectively. To this end, PROTACs have been developed as a group of engineered bi-functional chemical glues that induce the ubiquitination-mediated degradation of substrates via recruiting E3 ligases, such as CRL4 (CRBN) and CRL2 (pVHL). We summarize the recent major advances in the CRL4 research field towards understanding its involvement in tumorigenesis and further discuss its clinical implications. The anti-tumor effects using the PROTAC approach to target the degradation of undruggable targets are also highlighted.
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Affiliation(s)
- Ji Cheng
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Brian J North
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Pengbo Zhou
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, 1300 York Ave., New York, NY 10065, USA.
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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CUL4B promotes the pathology of adjuvant-induced arthritis in rats through the canonical Wnt signaling. J Mol Med (Berl) 2018; 96:495-511. [DOI: 10.1007/s00109-018-1635-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 02/07/2018] [Accepted: 03/22/2018] [Indexed: 12/19/2022]
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Shi B, Sharifi HJ, DiGrigoli S, Kinnetz M, Mellon K, Hu W, de Noronha CMC. Inhibition of HIV early replication by the p53 and its downstream gene p21. Virol J 2018; 15:53. [PMID: 29587790 PMCID: PMC5870690 DOI: 10.1186/s12985-018-0959-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 03/07/2018] [Indexed: 11/10/2022] Open
Abstract
Background The tumor suppressor gene p53 has been found to suppress HIV infection by various mechanisms, but the inhibition of HIV at an early stage of replication by host cell p53 and its downstream gene p21 has not been well studied. Method VSV-G pseudotyped HIV-1 or HIV-2 viruses with GFP or luciferase reporter gene were used to infect HCT116 p53+/+ cells, HCT116 p53−/− cells and hMDMs. The infections were detected by flow cytometry or measured by luciferase assay. Reverse transcription products were quantified by a TaqMan real time PCR. siRNA knockdown experiments were applied to study potential roles of p53 and p21 genes in their restriction to HIV infection. Western blot experiments were used to analyze changes in gene expression. Results The infection of HIV-1 was inhibited in HCT116 p53+/+ cells in comparison to HCT116 p53−/− cells. The fold of inhibition was largely increased when cell cycle switched from cycling to non-cycling status. Further analysis showed that both p53 and p21 expressions were upregulated in non-cycling HCT116 p53+/+ cells and HIV-1 reverse transcription was subsequently inhibited. siRNA knockdown of either p53 or p21 rescued HIV-1 reverse transcription from the inhibition in non-cycling HCT116 p53+/+ cells. It was identified that the observed restrictions by p53 and p21 were associated with the suppression of RNR2 expression and phosphorylation of SAMHD1. These observations were confirmed by using siRNA knockdown experiments. In addition, p53 also inhibited HIV-2 infection in HCT116 p53+/+ cells and siRNA knockdown of p21 increased HIV-2 infection in hMDMs. Finally the expressions of p53 and p21 were found to be induced in hMDMs shortly after HIV-1 infection. Conclusions The p53 and its downstream gene p21 interfere with HIV early stage of replication in non-cycling cells and hMDMs.
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Affiliation(s)
- Binshan Shi
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Ave, Albany, NY, 12208, USA.
| | - Hamayun J Sharifi
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Ave, Albany, NY, 12208, USA
| | - Sara DiGrigoli
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Ave, Albany, NY, 12208, USA
| | - Michaela Kinnetz
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Ave, Albany, NY, 12208, USA
| | - Katie Mellon
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, 106 New Scotland Ave, Albany, NY, 12208, USA
| | - Wenwei Hu
- Rutgers Cancer Institute of New Jersey, Rutgers the State University of New Jersey, New Brunswick, NJ, 08903, USA
| | - Carlos M C de Noronha
- Center for Immunology and Microbial Disease, Albany Medical College, Albany, New York, Albany, NY, 12208, USA
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Degradation of SAMHD1 by Vpx Is Independent of Uncoating. J Virol 2015; 89:5701-13. [PMID: 25762741 DOI: 10.1128/jvi.03575-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 03/05/2015] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Sterile alpha motif domain and HD domain-containing protein 1 (SAMHD1) restricts human immunodeficiency virus type 1 (HIV-1) replication in myeloid and resting T cells. Lentiviruses such as HIV-2 and some simian immunodeficiency viruses (SIVs) counteract the restriction by encoding Vpx or Vpr, accessory proteins that are packaged in virions and which, upon entry of the virus into the cytoplasm, induce the proteasomal degradation of SAMHD1. As a tool to study these mechanisms, we generated HeLa cell lines that express a fusion protein termed NLS.GFP.SAM595 in which the Vpx binding domain of SAMHD1 is fused to the carboxy terminus of green fluorescent protein (GFP) and a nuclear localization signal is fused to the amino terminus of GFP. Upon incubation of Vpx-containing virions with the cells, the NLS.GFP.SAM595 fusion protein was degraded over several hours and the levels remained low over 5 days as the result of continued targeting of the CRL4 E3 ubiquitin ligase. Degradation of the fusion protein required that it contain a nuclear localization sequence. Fusion to the cytoplasmic protein muNS rendered the protein resistant to Vpx-mediated degradation, confirming that SAMHD1 is targeted in the nucleus. Virions treated with protease inhibitors failed to release Vpx, indicating that Gag processing was required for Vpx release from the virion. Mutations in the capsid protein that altered the kinetics of virus uncoating and the Gag binding drug PF74 had no effect on the Vpx-mediated degradation. These results suggest that Vpx is released from virions without a need for uncoating of the capsid, allowing Vpx to transit to the nucleus rapidly upon entry into the cytoplasm. IMPORTANCE SAMHD1 restricts lentiviral replication in myeloid cells and resting T cells. Its importance is highlighted by the fact that viruses such as HIV-2 encode an accessory protein that is packaged in the virion and is dedicated to inducing SAMHD1 degradation. Vpx needs to act rapidly upon infection to allow reverse transcription to proceed. The limited number of Vpx molecules in a virion also needs to clear the cell of SAMHD1 over a prolonged period of time. Using an engineered HeLa cell line that expresses a green fluorescent protein (GFP)-SAMHD1 fusion protein, we showed that the Vpx-dependent degradation occurs without a need for viral capsid uncoating. In addition, the fusion protein was degraded only when it was localized to the nucleus, confirming that SAMHD1 is targeted in the nucleus and thus explaining why Vpx also localizes to the nucleus.
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Chen Z, Sui J, Zhang F, Zhang C. Cullin family proteins and tumorigenesis: genetic association and molecular mechanisms. J Cancer 2015; 6:233-42. [PMID: 25663940 PMCID: PMC4317758 DOI: 10.7150/jca.11076] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Accepted: 12/08/2014] [Indexed: 12/13/2022] Open
Abstract
Cullin family proteins function as scaffolds to form numerous E3 ubiquitin ligases with RING proteins, adaptor proteins and substrate recognition receptors. These E3 ligases further recognize numerous substrates to participate in a variety of cellular processes, such as DNA damage and repair, cell death and cell cycle progression. Clinically, cullin-associated E3 ligases have been identified to involve numerous human diseases, especially with regard to multiple cancer types. Over the past few years, our understanding of cullin proteins and their functions in genome stability and tumorigenesis has expanded enormously. Herein, this review briefly provides current perspectives on cullin protein functions, and mainly summarizes and discusses molecular mechanisms of cullin proteins in tumorigenesis.
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Affiliation(s)
- Zhi Chen
- 1. Orthopedics Department, Changhai Hospital Affiliated to Second Military Medical University, Shanghai, China, 200433
| | - Jie Sui
- 2. Orthopedics Department, 102 Hospital of People's Liberation Army, Changzhou, Jiangsu, China, 213003
| | - Fan Zhang
- 1. Orthopedics Department, Changhai Hospital Affiliated to Second Military Medical University, Shanghai, China, 200433
| | - Caiguo Zhang
- 3. Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA, 80045
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Yuan T, Yao W, Huang F, Sun B, Yang R. The human antiviral factor TRIM11 is under the regulation of HIV-1 Vpr. PLoS One 2014; 9:e104269. [PMID: 25105968 PMCID: PMC4126725 DOI: 10.1371/journal.pone.0104269] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 07/10/2014] [Indexed: 01/23/2023] Open
Abstract
TRIM11 has been reported to be able to restrict HIV-1 replication, but the detailed aspects of the interfering mechanisms remain unclear. In this study, we demonstrated that TRIM11 mainly suppressed the early steps of HIV-1 transduction, resulting in decreased reverse transcripts. Additionally, we found that TRIM11 could inhibit HIV-1 long terminal repeat (LTR) activity, which may be related to its inhibitory effects on NF-κB. Deletion mutant experiments showed that the RING domain of TRIM11 was indispensable in inhibiting the early steps of HIV-1 transduction but was dispensable in decreasing NF-κB and LTR activities. Moreover, we found that low levels of Vpr decreased TRIM11 protein levels, while high levels increased them, and these regulations were independent of the VprBP-associated proteasome machinery. These results suggest that the antiviral factor TRIM11 is indirectly regulated by HIV-1 Vpr through unknown mechanisms and that the concentration of Vpr is essential to these processes. Thus, our work confirms TRIM11 as a host cellular factor that interferes with the early steps of HIV-1 replication and provides a connection between viral protein and host antiviral factors.
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Affiliation(s)
- Ting Yuan
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Diseases, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China
| | - Weitong Yao
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Diseases, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China
| | - Fang Huang
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Diseases, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China
| | - Binlian Sun
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Diseases, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China
- * E-mail: (BS); (RY)
| | - Rongge Yang
- Research Group of HIV Molecular Epidemiology and Virology, Center for Emerging Infectious Diseases, The State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China
- * E-mail: (BS); (RY)
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Calistri A, Munegato D, Carli I, Parolin C, Palù G. The ubiquitin-conjugating system: multiple roles in viral replication and infection. Cells 2014; 3:386-417. [PMID: 24805990 PMCID: PMC4092849 DOI: 10.3390/cells3020386] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 04/23/2014] [Accepted: 04/24/2014] [Indexed: 12/17/2022] Open
Abstract
Through the combined action of ubiquitinating and deubiquitinating enzymes, conjugation of ubiquitin to a target protein acts as a reversible post-translational modification functionally similar to phosphorylation. Indeed, ubiquitination is more and more recognized as a central process for the fine regulation of many cellular pathways. Due to their nature as obligate intracellular parasites, viruses rely on the most conserved host cell machineries for their own replication. Thus, it is not surprising that members from almost every viral family are challenged by ubiquitin mediated mechanisms in different steps of their life cycle and have evolved in order to by-pass or exploit the cellular ubiquitin conjugating system to maximize their chance to establish a successful infection. In this review we will present several examples of the complex interplay that links viruses and the ubiquitin conjugation machinery, with a special focus on the mechanisms evolved by the human immunodeficiency virus to escape from cellular restriction factors and to exit from infected cells.
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Affiliation(s)
- Arianna Calistri
- Department of Molecular Medicine, University of Padova, via Gabelli 63, Padova 35121, Italy.
| | - Denis Munegato
- Department of Molecular Medicine, University of Padova, via Gabelli 63, Padova 35121, Italy.
| | - Ilaria Carli
- Department of Molecular Medicine, University of Padova, via Gabelli 63, Padova 35121, Italy.
| | - Cristina Parolin
- Department of Molecular Medicine, University of Padova, via Gabelli 63, Padova 35121, Italy.
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padova, via Gabelli 63, Padova 35121, Italy.
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