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Nyenhuis DA, Watanabe S, Bernstein R, Swenson RE, Raju N, Sabbasani VR, Mushti C, Lee D, Carter C, Tjandra N. Structural Relationships to Efficacy for Prazole-Derived Antivirals. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2308312. [PMID: 38447164 PMCID: PMC11095225 DOI: 10.1002/advs.202308312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/25/2024] [Indexed: 03/08/2024]
Abstract
Here, an in vitro characterization of a family of prazole derivatives that covalently bind to the C73 site on Tsg101 and assay their ability to inhibit viral particle production is presented. Structurally, increased steric bulk on the 4-pyridyl of the prazole expands the prazole site on the UEV domain toward the β-hairpin in the Ub-binding site and is coupled to increased inhibition of virus-like particle production in HIV-1. Increased bulk also increased toxicity, which is alleviated by increasing flexibility. Further, the formation of a novel secondary Tsg101 adduct for several of the tested compounds and the commercial drug lansoprazole. The secondary adduct involved the loss of the 4-pyridyl substituent to form an irreversible species, with implications for increasing the half-life of the active species or its specificity toward Tsg101 UEV. It is also determined that sulfide derivatives display effective viral inhibition, presumably through cellular sulfoxidation, allowing for delayed conversion within the cellular environment, and identify SARS-COV-2 as a target of prazole inhibition. These results open multiple avenues for the design of prazole derivatives for antiviral applications.
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Affiliation(s)
- David A. Nyenhuis
- Biochemistry and Biophysics CenterNHLBINIH50 South Drive, Bld 50, Rm 3503BethesdaMD20892USA
| | - Susan Watanabe
- Department of Microbiology and ImmunologyRenaissance School of MedicineStonybrook UniversityLife Sciences Bldg, Rm 248StonybrookNY11790USA
| | - Rebecca Bernstein
- Biochemistry and Biophysics CenterNHLBINIH50 South Drive, Bld 50, Rm 3503BethesdaMD20892USA
| | - Rolf E. Swenson
- Chemistry and Synthesis CenterNHLBINIH9800 Medical Center Drive, Bldg B, #2034RockvilleMD20850USA
| | - Natarajan Raju
- Chemistry and Synthesis CenterNHLBINIH9800 Medical Center Drive, Bldg B, #2034RockvilleMD20850USA
| | - Venkata R. Sabbasani
- Chemistry and Synthesis CenterNHLBINIH9800 Medical Center Drive, Bldg B, #2034RockvilleMD20850USA
| | - Chandrasekhar Mushti
- Chemistry and Synthesis CenterNHLBINIH9800 Medical Center Drive, Bldg B, #2034RockvilleMD20850USA
| | - Duck‐Yeon Lee
- Biochemistry Core FacilityNHLBINIHBethesdaMD20892USA
| | - Carol Carter
- Department of Microbiology and ImmunologyRenaissance School of MedicineStonybrook UniversityLife Sciences Bldg, Rm 248StonybrookNY11790USA
| | - Nico Tjandra
- Biochemistry and Biophysics CenterNHLBINIH50 South Drive, Bld 50, Rm 3503BethesdaMD20892USA
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Kim W, Lee GW, Rhee N, Min KH, Kim JH, Gil JY, Kim SY, Han JM, Lee KE. Risk factors for hyperglycemia in COVID-19 patients treated with remdesivir. Clin Transl Sci 2024; 17:e13684. [PMID: 37964480 PMCID: PMC10766056 DOI: 10.1111/cts.13684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/26/2023] [Accepted: 10/28/2023] [Indexed: 11/16/2023] Open
Abstract
The primary objective of this study was to investigate the factors contributing to hyperglycemic adverse events (AEs) associated with the administration of remdesivir in hospitalized patients diagnosed with coronavirus disease 2019 (COVID-19). Furthermore, the study aimed to develop a risk score model employing various machine learning approaches. A total of 1262 patients were enrolled in this investigation. The relationship between covariates and hyperglycemic AEs was assessed through logistic regression analysis. Diverse machine learning algorithms were employed for the purpose of forecasting hyperglycemia-related complications. After adjusting for covariates, individuals with a body mass index ≥23 kg/m2 , those using proton pump inhibitors, cholinergic medications, or individuals with cardiovascular diseases exhibited approximately 2.41-, 2.73-, 2.65-, and 1.97-fold higher risks of experiencing hyperglycemic AEs (95% CI 1.271-4.577, 1.223-6.081, 1.168-5.989, and 1.119-3.472, respectively). Multivariate logistic regression, elastic net, and random forest models displayed area under the receiver operating characteristic curve values of 0.65, 0.66, and 0.60, respectively (95% CI 0.572-0.719, 0.640-0.671, and 0.583-0.611, respectively). This study comprehensively explored factors associated with hyperglycemic complications arising from remdesivir administration and, concurrently, leveraged a range of machine learning methodologies to construct a risk scoring model, thereby facilitating the tailoring of individualized remdesivir treatment regimens for patients with COVID-19.
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Affiliation(s)
- Woorim Kim
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
- Department of PharmacyKangwon National UniversityChuncheonKorea
| | - Go Woon Lee
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
- Department of PharmacyBestian HospitalCheongju‐siKorea
| | - Nuga Rhee
- Medical DepartmentBestian HospitalCheongju‐siKorea
| | - Kyung Hyun Min
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
| | - Jun Hyeob Kim
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
| | - Jin Yeon Gil
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
| | - Song Yi Kim
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
- National Institute of Food and Drug Safety EvaluationCheongju‐siKorea
| | - Ji Min Han
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
| | - Kyung Eun Lee
- College of PharmacyChungbuk National UniversityCheongju‐siKorea
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3
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Dai J, Feng Y, Liao Y, Tan L, Sun Y, Song C, Qiu X, Ding C. ESCRT machinery and virus infection. Antiviral Res 2024; 221:105786. [PMID: 38147902 DOI: 10.1016/j.antiviral.2023.105786] [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: 10/25/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/28/2023]
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery plays a significant role in the spread of human viruses. However, our understanding of how the host ESCRT machinery responds to viral infection remains limited. Emerging evidence suggests that the ESCRT machinery can be hijacked by viruses of different families to enhance their replication. Throughout their life cycle, these viruses can interfere with or exploit ESCRT-mediated physiological processes to increase their chances of infecting the host. In contrast, to counteract virus infection, the interferon-stimulated gene 15 (ISG15) or the E3 ISG15-protein ligase (HERC5) system within the infected cells is activated to degrade the ESCRT proteins. Many retroviral and RNA viral proteins have evolved "late (L) domain" motifs, which enable them to recruit host ESCRT subunit proteins to facilitate virus transport, replication, budding, mature, and even endocytosis, Therefore, the L domain motifs and ESCRT subunit proteins could serve as promising drug targets for antiviral therapy. This review investigated the composition and essential functions of the ESCRT, shedding light on the impact of ESCRT subunits and viral L domain motifs on the replication of viruses. Furthermore, the antiviral effects facilitated by the ESCRT machinery have been investigated, aiming to provide valuable insights to guide the development and utilization of antiviral drugs.
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Affiliation(s)
- Jun Dai
- Experimental Animal Center, Zunyi Medical University, Zunyi, 563099, China; Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Yiyi Feng
- Laboratory of Veterinary Microbiology and Animal Infectious Diseases, College of Animal Sciences and Veterinary Medicine, Guangxi University, Nanning, 530004, Guangxi, China.
| | - Ying Liao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Lei Tan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Yingjie Sun
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Cuiping Song
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Xusheng Qiu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
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4
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Wojaczyńska E, Wojaczyński J. Sulfoxides in medicine. Curr Opin Chem Biol 2023; 76:102340. [PMID: 37307682 DOI: 10.1016/j.cbpa.2023.102340] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/13/2023] [Accepted: 05/16/2023] [Indexed: 06/14/2023]
Abstract
In the review, current status of sulfoxides on the pharmaceutical market is discussed. In the first part of the article, natural sulfoxides will be described with a special focus on sulforaphane and amanitin, a mushroom toxin which has been developed as payload in antibody drug conjugates in the possible cancer treatment. Controversies associated with the medical use of dimethylsulfoxide are briefly described in the next section. In the part devoted to PPIs, the benefits of using pure enantiomers (chiral switch) are discussed. An interesting approach, repositioning of drugs is exemplified by new possible applications of modafinil and sulindac. The review is concluded by presentation of cenicriviroc and adezmapimod, both with the status of promising drug candidates.
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Affiliation(s)
- Elżbieta Wojaczyńska
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50 370, Wrocław, Poland.
| | - Jacek Wojaczyński
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., 50 383, Wrocław, Poland
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Le TK, Park YJ, Cha GS, Oktavia FARH, Kim DH, Yun CH. Roles of Human Liver Cytochrome P450 Enzymes in Tenatoprazole Metabolism. Pharmaceutics 2022; 15:pharmaceutics15010023. [PMID: 36678652 PMCID: PMC9863764 DOI: 10.3390/pharmaceutics15010023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/05/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
Tenatoprazole, a newly developed proton pump inhibitor candidate, was developed as an acid inhibitor for gastric acid hypersecretion disorders such as gastric ulcer and reflux esophagitis. It is known that tenatoprazole is metabolized to three major metabolites of 5'-hydroxy tenatoprazole, tenatoprazole sulfide, and tenatoprazole sulfone in human liver, primarily catalyzed by CYPs 2C19 and 3A4. While CYP2C19 prefers the hydroxylation of tenatoprazole at C-5' position, CYP3A4 is mainly involved in sulfoxidation reaction to make tenatoprazole sulfone. Tenatoprazole sulfide is a major human metabolite of tenatoprazole and is formed spontaneously and non-enzymatically from tenatoprazole. However, its metabolic fate in the human liver is not fully known. Furthermore, no systematic metabolic study has been performed to study tenatoprazole or tenatoprazole sulfide. Here, we studied the functions of human cytochromes P450 in the metabolic pathway of tenatoprazole and tenatoprazole sulfide by using recombinant human P450s and human liver microsomes. Both CYP 2C19 and CYP3A4 showed distinct regioselective and stereospecific monooxygenation activities toward tenatoprazole and tenatoprazole sulfide. Furthermore, a new major metabolite of tenatoprazole sulfide was found, 1'-N-oxy-5'-hydroxytenatoprzole sulfide, which has never been reported. In conclusion, the metabolic fates of tenatoprazole and tenatoprazole sulfide should be considered in the clinical use of tenatoprazole.
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Affiliation(s)
- Thien-Kim Le
- School of Biological Sciences and Technology, Chonnam National University, 77 Yongbongro, Gwangju 61186, Republic of Korea
| | - Young Jin Park
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, College of Medicine, Bokjiro 75, Busanjin-Gu, Busan 47392, Republic of Korea
| | - Gun Su Cha
- Namhae Garlic Research Institute, 2465-8 Namhaedaero, Namhae-gun, Gyeongsang-namdo 52430, Republic of Korea
| | - Fikri A. R. Hardiyanti Oktavia
- School of Biological Sciences and Biotechnology, Graduate School, Chonnam National University, 77 Yongbongro, Gwangju 61186, Republic of Korea
| | - Dong Hyun Kim
- Department of Pharmacology and Pharmacogenomics Research Center, Inje University, College of Medicine, Bokjiro 75, Busanjin-Gu, Busan 47392, Republic of Korea
- Correspondence: (D.H.K.); (C.-H.Y.)
| | - Chul-Ho Yun
- School of Biological Sciences and Technology, Chonnam National University, 77 Yongbongro, Gwangju 61186, Republic of Korea
- Correspondence: (D.H.K.); (C.-H.Y.)
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Proposal to Consider Chemical/Physical Microenvironment as a New Therapeutic Off-Target Approach. Pharmaceutics 2022; 14:pharmaceutics14102084. [PMID: 36297518 PMCID: PMC9611316 DOI: 10.3390/pharmaceutics14102084] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/26/2022] [Accepted: 09/28/2022] [Indexed: 11/22/2022] Open
Abstract
The molecular revolution could lead drug discovery from chance observation to the rational design of new classes of drugs that could simultaneously be more effective and less toxic. Unfortunately, we are witnessing some failure in this sense, and the causes of the crisis involve a wide range of epistemological and scientific aspects. In pharmacology, one key point is the crisis of the paradigm the “magic bullet”, which is to design therapies based on specific molecular targets. Drug repurposing is one of the proposed ways out of the crisis and is based on the off-target effects of known drugs. Here, we propose the microenvironment as the ideal place to direct the off-targeting of known drugs. While it has been extensively investigated in tumors, the generation of a harsh microenvironment is also a phenotype of the vast majority of chronic diseases. The hostile microenvironment, on the one hand, reduces the efficacy of both chemical and biological drugs; on the other hand, it dictates a sort of “Darwinian” selection of those cells armed to survive in such hostile conditions. This opens the way to the consideration of the microenvironment as a convenient target for pharmacological action, with a clear example in proton pump inhibitors.
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7
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A review on lactoferrin as a proton pump inhibitor. Int J Biol Macromol 2022; 202:309-317. [PMID: 35038474 DOI: 10.1016/j.ijbiomac.2022.01.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 12/12/2022]
Abstract
Lactoferrin (Lf) is a versatile natural milk-derived protein that exhibits multiple interesting biological activities. Since it is safe for human administration and currently manufactured using low cost and well-established large-scale processes, the Lf scientific community has been devoted at dissecting its mechanisms of action towards its more rational and efficient use for various applications. Emerging literature has identified proton pumping ATPases as molecular targets of Lf in different cellular models linked to distinct activities of this natural protein. Information on this subject has not been systematically analysed before, hence herein we review the current state of art on the effect of Lf on proton pumping ATPases. Though structurally different, we propose that Lf holds a proton pump inhibitor (PPI)-like activity based on the functional resemblance with the classical inhibitors of the stomach H+/K+-ATPase. The downstream events and outcomes of the PPI-like activity of Lf, as well as its impact for the development of improved Lf applications are also discussed.
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8
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Chua HH, Kameyama T, Mayeda A, Yeh TH. Epstein-Barr Virus Enhances Cancer-Specific Aberrant Splicing of TSG101 Pre-mRNA. Int J Mol Sci 2022; 23:ijms23052516. [PMID: 35269659 PMCID: PMC8910672 DOI: 10.3390/ijms23052516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/21/2022] [Accepted: 02/21/2022] [Indexed: 11/16/2022] Open
Abstract
Tumor viruses gain control of cellular functions when they infect and transform host cells. Alternative splicing is one of the cellular processes exploited by tumor viruses to benefit viral replication and support oncogenesis. Epstein-Barr virus (EBV) participates in a number of cancers, as reported mostly in nasopharyngeal carcinoma (NPC) and Burkitt lymphoma (BL). Using RT-nested-PCR and Northern blot analysis in NPC and BL cells, here we demonstrate that EBV promotes specific alternative splicing of TSG101 pre-mRNA, which generates the TSG101∆154-1054 variant though the agency of its viral proteins, such as EBNA-1, Zta and Rta. The level of TSG101∆154-1054 is particularly enhanced upon EBV entry into the lytic cycle, increasing protein stability of TSG101 and causing the cumulative synthesis of EBV late lytic proteins, such as VCA and gp350/220. TSG101∆154-1054-mediated production of VCA and gp350/220 is blocked by the overexpression of a translational mutant of TSG101∆154-1054 or by the depletion of full-length TSG101, which is consistent with the known role of the TSG101∆154-1054 protein in stabilizing the TSG101 protein. NPC patients whose tumor tissues express TSG101∆154-1054 have high serum levels of anti-VCA antibodies and high levels of viral DNA in their tumors. Our findings highlight the functional importance of TSG101∆154-1054 in allowing full completion of the EBV lytic cycle to produce viral particles. We propose that targeting EBV-induced TSG101 alternative splicing has broad potential as a therapeutic to treat EBV-associated malignancies.
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Affiliation(s)
- Huey-Huey Chua
- Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 100226, Taiwan;
| | - Toshiki Kameyama
- Department of Physiology, School of Medicine, Fujita Health University, Toyoake 470-1192, Aichi, Japan;
| | - Akila Mayeda
- Division of Gene Expression Mechanism, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Aichi, Japan
- Correspondence: (A.M.); (T.-H.Y.)
| | - Te-Huei Yeh
- Department of Otolaryngology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 100225, Taiwan
- Correspondence: (A.M.); (T.-H.Y.)
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Diphyllin Shows a Broad-Spectrum Antiviral Activity against Multiple Medically Important Enveloped RNA and DNA Viruses. Viruses 2022; 14:v14020354. [PMID: 35215947 PMCID: PMC8874615 DOI: 10.3390/v14020354] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 12/10/2022] Open
Abstract
Diphyllin is a natural arylnaphtalide lignan extracted from tropical plants of particular importance in traditional Chinese medicine. This compound has been described as a potent inhibitor of vacuolar (H+)ATPases and hence of the endosomal acidification process that is required by numerous enveloped viruses to trigger their respective viral infection cascades after entering host cells by receptor-mediated endocytosis. Accordingly, we report here a revised, updated, and improved synthesis of diphyllin, and demonstrate its antiviral activities against a panel of enveloped viruses from Flaviviridae, Phenuiviridae, Rhabdoviridae, and Herpesviridae families. Diphyllin is not cytotoxic for Vero and BHK-21 cells up to 100 µM and exerts a sub-micromolar or low-micromolar antiviral activity against tick-borne encephalitis virus, West Nile virus, Zika virus, Rift Valley fever virus, rabies virus, and herpes-simplex virus type 1. Our study shows that diphyllin is a broad-spectrum host cell-targeting antiviral agent that blocks the replication of multiple phylogenetically unrelated enveloped RNA and DNA viruses. In support of this, we also demonstrate that diphyllin is more than just a vacuolar (H+)ATPase inhibitor but may employ other antiviral mechanisms of action to inhibit the replication cycles of those viruses that do not enter host cells by endocytosis followed by low pH-dependent membrane fusion.
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Tsg101/ESCRT-I recruitment regulated by the dual binding modes of K63-linked diubiquitin. Structure 2022; 30:289-299.e6. [PMID: 35120596 PMCID: PMC10015442 DOI: 10.1016/j.str.2021.09.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/03/2021] [Accepted: 09/14/2021] [Indexed: 11/23/2022]
Abstract
The ESCRT-I protein Tsg101 plays a critical role in viral budding and endocytic sorting. Although Tsg101 is known to recognize monoubiquitin (Ub1), here we show that it can also bind several diubiquitins (K48-Ub2, N-Ub2, and K63-Ub2), with a preference for K63-linked Ub2. The NMR structure of the Tsg101:K63-Ub2 complex showed that while the Ub1-binding site accommodates the distal domain of Ub2, the proximal domain alternatively binds two different sites, the vestigial active site and an N-terminal helix. Mutation of each site results in distinct phenotypes regarding the recruitment of Tsg101 partners. Mutation in the vestigial active site abrogates interaction between Tsg101 and the HIV-1 protein Gag but not Hrs, a cellular protein. Mutation at the N-terminal helix alters Gag but not Hrs-Tsg101 localization. Given the broad involvement of Tsg101 in diverse cellular functions, this discovery advances our understanding of how the ESCRT protein recognizes binding partners and sorts endocytic cargo.
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Stress-Induced Epstein-Barr Virus Reactivation. Biomolecules 2021; 11:biom11091380. [PMID: 34572593 PMCID: PMC8470332 DOI: 10.3390/biom11091380] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 12/18/2022] Open
Abstract
Epstein-Barr virus (EBV) is typically found in a latent, asymptomatic state in immunocompetent individuals. Perturbations of the host immune system can stimulate viral reactivation. Furthermore, there are a myriad of EBV-associated illnesses including various cancers, post-transplant lymphoproliferative disease, and autoimmune conditions. A thorough understanding of this virus, and the interplay between stress and the immune system, is essential to establish effective treatment. This review will provide a summary of the interaction between both psychological and cellular stressors resulting in EBV reactivation. It will examine mechanisms by which EBV establishes and maintains latency and will conclude with a brief overview of treatments targeting EBV.
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Welker L, Paillart JC, Bernacchi S. Importance of Viral Late Domains in Budding and Release of Enveloped RNA Viruses. Viruses 2021; 13:1559. [PMID: 34452424 PMCID: PMC8402826 DOI: 10.3390/v13081559] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/09/2023] Open
Abstract
Late assembly (L) domains are conserved sequences that are necessary for the late steps of viral replication, acting like cellular adaptors to engage the ESCRT membrane fission machinery that promote virion release. These short sequences, whose mutation or deletion produce the accumulation of immature virions at the plasma membrane, were firstly identified within retroviral Gag precursors, and in a further step, also in structural proteins of many other enveloped RNA viruses including arenaviruses, filoviruses, rhabdoviruses, reoviruses, and paramyxoviruses. Three classes of L domains have been identified thus far (PT/SAP, YPXnL/LXXLF, and PPxY), even if it has recently been suggested that other motifs could act as L domains. Here, we summarize the current state of knowledge of the different types of L domains and their cellular partners in the budding events of RNA viruses, with a particular focus on retroviruses.
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Affiliation(s)
| | | | - Serena Bernacchi
- Architecture et Réactivité de l’ARN, UPR 9002, IBMC, CNRS, Université de Strasbourg, F-67000 Strasbourg, France; (L.W.); (J.-C.P.)
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13
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Novel Tsg101 Binding Partners Regulate Viral L Domain Trafficking. Viruses 2021; 13:v13061147. [PMID: 34203832 PMCID: PMC8232796 DOI: 10.3390/v13061147] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/07/2021] [Accepted: 06/09/2021] [Indexed: 02/06/2023] Open
Abstract
Two decades ago, Tsg101, a component of the Endosomal Sorting Complexes Required for Transport (ESCRT) complex 1, was identified as a cellular factor recruited by the human immunodeficiency virus type 1 (HIV-1) to facilitate budding of viral particles assembled at the cell periphery. A highly conserved Pro-(Thr/Ser)-Ala-Pro [P(T/S)AP] motif in the HIV-1 structural polyprotein, Gag, engages a P(T/S)AP-binding pocket in the Tsg101 N-terminal domain. Since the same domain in Tsg101 that houses the pocket was found to bind mono-ubiquitin (Ub) non-covalently, Ub binding was speculated to enhance P(T/S)AP interaction. Within the past five years, we found that the Ub-binding site also accommodates di-Ub, with Lys63-linked di-Ub exhibiting the highest affinity. We also identified small molecules capable of disrupting Ub binding and inhibiting budding. The structural similarity of these molecules, prazoles, to nucleosides prompted testing for nucleic acid binding and led to identification of tRNA as a Tsg101 binding partner. Here, we discuss these recently identified interactions and their contribution to the viral assembly process. These new partners may provide additional insight into the control and function of Tsg101 as well as identify opportunities for anti-viral drug design.
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14
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Prazoles Targeting Tsg101 Inhibit Release of Epstein-Barr Virus following Reactivation from Latency. J Virol 2021; 95:e0246620. [PMID: 33853959 DOI: 10.1128/jvi.02466-20] [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: 01/09/2023] Open
Abstract
Epstein-Barr virus (EBV) is a ubiquitous herpesvirus responsible for several diseases, including cancers of lymphoid and epithelial cells. EBV cancers typically exhibit viral latency; however, the production and release of EBV through its lytic phase are essential for cancer development. Antiviral agents that specifically target EBV production do not currently exist. Previously, we reported that the proton pump inhibitor tenatoprazole, which blocks the interaction of ubiquitin with the ESCRT-1 factor Tsg101, inhibits production of several enveloped viruses, including EBV. Here, we show that three structurally distinct prazoles impair mature particle formation postreactivation and identify the impact on stages of replication. The prazoles did not impair expression of lytic genes representative of the different kinetic classes but interfered with capsid maturation in the nucleus as well as virion transport from the nucleus. Replacement of endogenous Tsg101 with a mutant Tsg101 refractory to prazole-mediated inhibition rescued EBV release. These findings directly implicate Tsg101 in EBV nuclear egress and identify prazoles as potential therapeutic candidates for conditions that rely on EBV replication, such as chronic active EBV infection and posttransplant lymphoproliferative disorders. IMPORTANCE Production of virions is necessary for the ubiquitous Epstein-Barr virus (EBV) to persist in humans and can set the stage for development of EBV cancers in at-risk individuals. In our attempts to identify inhibitors of the EBV lytic phase, we previously found that a prazole proton pump inhibitor, known to block the interaction of ubiquitin with the ESCRT-1 factor Tsg101, blocks production of EBV. We now find that three structurally distinct prazoles impair maturation of EBV capsids and virion transport from the nucleus and, by interfering with Tsg101, prevent EBV release from lytically active cells. Our findings not only implicate Tsg101 in EBV production but also identify widely used prazoles as candidates to prevent development of posttransplant EBV lymphomas.
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15
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Ilaprazole and other novel prazole-based compounds that bind Tsg101 inhibit viral budding of HSV-1/2 and HIV from cells. J Virol 2021; 95:JVI.00190-21. [PMID: 33731460 PMCID: PMC8139698 DOI: 10.1128/jvi.00190-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In many enveloped virus families, including HIV and HSV, a crucial, yet unexploited, step in the viral life cycle is releasing particles from the infected cell membranes. This release process is mediated by host ESCRT complex proteins, which are recruited by viral structural proteins and provides the mechanical means for membrane scission and subsequent viral budding. The prazole drug, tenatoprazole, was previously shown to bind to ESCRT complex member Tsg101 and to quantitatively block the release of infectious HIV-1 from cells in culture. In this report we show that tenatoprazole and a related prazole drug, ilaprazole, effectively block infectious Herpes Simplex Virus (HSV)-1/2 release from Vero cells in culture. By electron microscopy, we found that both prazole drugs block the transit of HSV particles through the cell nuclear membrane resulting in their accumulation in the nucleus. Ilaprazole also quantitatively blocks the release of HIV-1 from 293T cells with an EC50 of 0.8-1.2 μM, which is much more potent than tenatoprazole. Our results indicate that prazole-based compounds may represent a class of drugs with potential to be broad-spectrum antiviral agents against multiple enveloped viruses, by interrupting cellular Tsg101 interaction with maturing virus, thus blocking the budding process that releases particles from the cell.ImportanceThese results provide the basis for the development of drugs that target enveloped virus budding that can be used ultimately to control multiple virus infections in humans.
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Böhm R, Bulin C, Waetzig V, Cascorbi I, Klein HJ, Herdegen T. Pharmacovigilance-based drug repurposing: The search for inverse signals via OpenVigil identifies putative drugs against viral respiratory infections. Br J Clin Pharmacol 2021; 87:4421-4431. [PMID: 33871897 DOI: 10.1111/bcp.14868] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 03/25/2021] [Accepted: 04/06/2021] [Indexed: 12/19/2022] Open
Affiliation(s)
- Ruwen Böhm
- Institute of Experimental and Clinical Pharmacology, University Hospital Schleswig-Holstein Campus Kiel, Germany
| | - Claudia Bulin
- Institute of Experimental and Clinical Pharmacology, University Hospital Schleswig-Holstein Campus Kiel, Germany
| | - Vicki Waetzig
- Institute of Experimental and Clinical Pharmacology, University Hospital Schleswig-Holstein Campus Kiel, Germany
| | - Ingolf Cascorbi
- Institute of Experimental and Clinical Pharmacology, University Hospital Schleswig-Holstein Campus Kiel, Germany
| | | | - Thomas Herdegen
- Institute of Experimental and Clinical Pharmacology, University Hospital Schleswig-Holstein Campus Kiel, Germany
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17
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Why Cells and Viruses Cannot Survive without an ESCRT. Cells 2021; 10:cells10030483. [PMID: 33668191 PMCID: PMC7995964 DOI: 10.3390/cells10030483] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/19/2021] [Accepted: 02/21/2021] [Indexed: 12/15/2022] Open
Abstract
Intracellular organelles enwrapped in membranes along with a complex network of vesicles trafficking in, out and inside the cellular environment are one of the main features of eukaryotic cells. Given their central role in cell life, compartmentalization and mechanisms allowing their maintenance despite continuous crosstalk among different organelles have been deeply investigated over the past years. Here, we review the multiple functions exerted by the endosomal sorting complex required for transport (ESCRT) machinery in driving membrane remodeling and fission, as well as in repairing physiological and pathological membrane damages. In this way, ESCRT machinery enables different fundamental cellular processes, such as cell cytokinesis, biogenesis of organelles and vesicles, maintenance of nuclear–cytoplasmic compartmentalization, endolysosomal activity. Furthermore, we discuss some examples of how viruses, as obligate intracellular parasites, have evolved to hijack the ESCRT machinery or part of it to execute/optimize their replication cycle/infection. A special emphasis is given to the herpes simplex virus type 1 (HSV-1) interaction with the ESCRT proteins, considering the peculiarities of this interplay and the need for HSV-1 to cross both the nuclear-cytoplasmic and the cytoplasmic-extracellular environment compartmentalization to egress from infected cells.
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18
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Conrad KP. Might proton pump or sodium-hydrogen exchanger inhibitors be of value to ameliorate SARs-CoV-2 pathophysiology? Physiol Rep 2021; 8:e14649. [PMID: 33369281 PMCID: PMC7762781 DOI: 10.14814/phy2.14649] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/26/2022] Open
Abstract
Discovering therapeutics for COVID-19 is a priority. Besides high-throughput screening of compounds, candidates might be identified based on their known mechanisms of action and current understanding of the SARs-CoV-2 life cycle. Using this approach, proton pump (PPIs) and sodium-hydrogen exchanger inhibitors (NHEIs) emerged, because of their potential to inhibit the release of extracellular vesicles (EVs; exosomes and/or microvesicles) that could promote disease progression, and to directly disrupt SARs-CoV-2 pathogenesis. If EVs exacerbate SARs-CoV-2 infection as suggested for other viruses, then inhibiting EV release by PPIs/NHEIs should be beneficial. Mechanisms underlying inhibition of EV release by these drugs remain uncertain, but may involve perturbing endosomal pH especially of multivesicular bodies where intraluminal vesicles (nascent exosomes) are formed. Additionally, PPIs might inhibit the endosomal sorting complex for transport machinery involved in EV biogenesis. Through perturbing endocytic vesicle pH, PPIs/NHEIs could also impede cleavage of SARs-CoV-2 spike protein by cathepsins necessary for viral fusion with the endosomal membrane. Although pulmonary epithelial cells may rely mainly on plasma membrane serine protease TMPRSS2 for cell entry, PPIs/NHEIs might be efficacious in ACE2-expressing cells where viral endocytosis is the major or a contributing entry pathway. These pharmaceutics might also perturb pH in the endoplasmic reticulum-Golgi intermediate and Golgi compartments, thereby potentially disrupting viral assembly and glycosylation of spike protein/ACE2, respectively. A caveat, however, is that facilitation not inhibition of avian infectious bronchitis CoV pathogenesis was reported in one study after increasing Golgi pH. Envelope protein-derived viroporins contributed to pulmonary edema formation in mice infected with SARs-CoV. If similar pathogenesis occurs with SARs-CoV-2, then blocking these channels with NHEIs could ameliorate disease pathogenesis. To ascertain their potential efficacy, PPIs/NHEIs need evaluation in cell and animal models at various phases of SARs-CoV-2 infection. If they prove to be therapeutic, the greatest benefit might be realized with the administration before the onset of severe cytokine release syndrome.
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Affiliation(s)
- Kirk P. Conrad
- Departments of Physiology and Functional Genomics, and of Obstetrics and GynecologyUniversity of Florida College of MedicineGainesvilleFLUSA
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19
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Mousavi SZ, Rahmanian M, Sami A. A connectivity map-based drug repurposing study and integrative analysis of transcriptomic profiling of SARS-CoV-2 infection. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2020; 86:104610. [PMID: 33130005 PMCID: PMC7598903 DOI: 10.1016/j.meegid.2020.104610] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 09/29/2020] [Accepted: 10/23/2020] [Indexed: 12/15/2022]
Abstract
AIMS The recent outbreak of COVID-19 has become a global health concern. There are currently no effective treatment strategies and vaccines for the treatment or prevention of this fatal disease. The current study aims to determine promising treatment options for the COVID-19 through a computational drug repurposing approach. MATERIALS AND METHODS In this study, we focus on differentially expressed genes (DEGs), detected in SARS-CoV-2 infected cell lines including "the primary human lung epithelial cell line NHBE" and "the transformed lung alveolar cell line A549". Next, the identified DEGs are used in the connectivity map (CMap) analysis to identify similarly acting therapeutic candidates. Furthermore, to interpret lists of DEGs, pathway enrichment and protein network analysis are performed. Genes are categorized into easily interpretable pathways based on their biological functions, and overrepresentation of each pathway is tested in comparison to what is expected randomly. KEY FINDINGS The results suggest the effectiveness of lansoprazole, folic acid, sulfamonomethoxine, tolnaftate, diclofenamide, halcinonide, saquinavir, metronidazole, ebselen, lidocaine and benzocaine, histone deacetylase (HDAC) inhibitors, heat shock protein 90 (HSP90) inhibitors, and many other clinically approved drugs as potent drugs against COVID-19 outbreak. SIGNIFICANCE Making new drugs remain a lengthy process, so the drug repurposing approach provides an insight into the therapeutics that might be helpful in this pandemic. In this study, pathway enrichment and protein network analysis are also performed, and the effectiveness of some drugs obtained from the CMap analysis has been investigated according to previous researches.
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20
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Xu Q, Jia X, Wu Q, Shi L, Ma Z, Ba N, Zhao H, Xia X, Zhang Z. Esomeprazole affects the proliferation, metastasis, apoptosis and chemosensitivity of gastric cancer cells by regulating lncRNA/circRNA-miRNA-mRNA ceRNA networks. Oncol Lett 2020; 20:329. [PMID: 33101498 PMCID: PMC7577076 DOI: 10.3892/ol.2020.12193] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/07/2020] [Indexed: 12/11/2022] Open
Abstract
Recently, proton pump inhibitors have become a hot research topic in the field of cancer drug research. However, the specific anti-tumor effect and underlying mechanisms of esomeprazole (ESO) in gastric cancer (GC) have remained elusive. In the present study, the toxic effects of ESO on the GC cell line AGS were investigated. MTT assays confirmed that ESO inhibited the proliferation of AGS cells and significantly enhanced their chemosensitivity. Transwell assays were performed to determine the anti-metastatic effects of ESO in AGS cells. Flow cytometry demonstrated that ESO induced cell apoptosis and caused cell cycle arrest in the S and G2/M phases. Furthermore, the differential expression of 948 long non-coding RNAs (lncRNAs), 114 circular RNAs (circRNAs), 1,197 mRNAs and 199 microRNAs (miRNAs) was detected in AGS cells via microarray analysis and RNA-sequencing. The top 10 differently expressed genes were mostly located on chromosomes 10 and 19. In addition, Gene Ontology analysis indicated that the genes were accumulated in functional terms associated with DNA replication, the cell cycle and the apoptotic signaling pathway. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed a variety of significantly dysregulated signaling pathways and targets, including the EGFR tyrosine kinase inhibitor resistance pathway, forkhead box O signaling pathway, p53 signaling pathway and platinum drug resistance pathway. Subsequently, the interactions of microtubule-associated protein 2 (MAP2), homeodomain-interacting protein kinase 2 (HIPK2) and ankyrin 2 (ANK2) were noted in a competing endogenous RNA (ceRNA) network, which may be important targets of ESO, exerting an anti-tumor effect in AGS cells. Collectively, ESO affects the proliferation, metastasis, apoptosis and chemosensitivity of gastric cancer cells by regulating long non-coding RNA/circRNA-miRNA-mRNA ceRNA networks.
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Affiliation(s)
- Qian Xu
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Xiyun Jia
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Qian Wu
- Department of Gastroenterology, Huanghe Central Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Lei Shi
- Department of Clinical Pharmacy, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Zihan Ma
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Nan Ba
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Han Zhao
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Xingzhou Xia
- Department of Gastroenterology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Zisen Zhang
- Department of Oncology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
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21
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Ray A, Sharma S, Sadasivam B. The Potential Therapeutic Role of Proton Pump Inhibitors in COVID-19: Hypotheses Based on Existing Evidences. Drug Res (Stuttg) 2020; 70:484-488. [PMID: 32877948 PMCID: PMC7672704 DOI: 10.1055/a-1236-3041] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Although the major therapeutic uses of the proton pump inhibitors are in gastric-acid related diseases, evidences are suggestive of a pleiotropic nature of the compounds. We comment on the probable pathways and cellular machineries via which proton pump inhibitors could show beneficial therapeutic effects against SARS-CoV-2 based on the existing evidences. Proton pump inhibitors have shown antiviral potencies in various in vivo and in vitro studies. Some of the major possible ways through which they can act against SARS-CoV-2 are by exerting anti-inflammatory and anti-fibrotic effects, via vacuolar ATPase pumps leading to raised endolysosomal pH and by targeting endosomal complexes. The current pandemic has put forward a challenge to find treatment options. Although the potential roles of proton pump inhibitors against SARS-CoV-2 have been discussed in recent publications, the clinical evidences for their real-world effectiveness do not point towards a beneficial effect clearly yet. We suggest that although proton pump inhibitors should strongly be considered as potential therapeutic options for COVID-19, larger studies in the form of randomized controlled trials would be required to arrive at a definite conclusion.
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Affiliation(s)
- Avik Ray
- Department of Pharmacology, All India Institute of Medical Sciences Bhopal, Bhopal, Madhya Pradesh, India
| | - Swati Sharma
- Department of Pharmacology, All India Institute of Medical Sciences Bhopal, Bhopal, Madhya Pradesh, India
| | - Balakrishnan Sadasivam
- Department of Pharmacology, All India Institute of Medical Sciences Bhopal, Bhopal, Madhya Pradesh, India
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Watanabe SM, Strickland M, Tjandra N, Carter CA. RNA Binding Suppresses Tsg101 Recognition of Ub-Modified Gag and Facilitates Recruitment to the Plasma Membrane. Viruses 2020; 12:v12040447. [PMID: 32326417 PMCID: PMC7232412 DOI: 10.3390/v12040447] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/07/2020] [Accepted: 04/10/2020] [Indexed: 01/09/2023] Open
Abstract
The ESCRT-I factor Tsg101 is essential for sorting endocytic cargo and is exploited by viral pathogens to facilitate egress from cells. Both the nucleocapsid (NC) domain and p6 domain in HIV-1 Gag contribute to recruitment of the protein. However, the role of NC is unclear when the P(S/T)AP motif in p6 is intact, as the motif recruits Tsg101 directly. The zinc fingers in NC bind RNA and membrane and are critical for budding. Tsg101 can substitute for the distal ZnF (ZnF2) and rescue budding of a mutant made defective by deletion of this element. Here, we report that the ubiquitin (Ub) E2 variant (UEV) domain in Tsg101 binds tRNA in vitro. We confirmed that Tsg101 can substitute for ZnF2 when provided at the viral assembly site as a chimeric Gag-Tsg101 protein (Gag-ΔZnF2-Tsg101) and rescue budding. The UEV was not required in this context; however, mutation of the RNA binding determinants in UEV prevented Tsg101 recruitment from the cell interior when Gag and Tsg101 were co-expressed. The same Tsg101 mutations increased recognition of Gag-Ub, suggesting that tRNA and Ub compete for binding sites. This study identifies a novel Tsg101 binding partner that may contribute to its function in recognition of Ub-modified cargo.
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Affiliation(s)
- Susan M. Watanabe
- Department of Microbiology & Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794-5222, USA;
| | - Madeleine Strickland
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Nico Tjandra
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA;
- Correspondence: (N.T.); (C.A.C.); Tel.: +1-631-632-8801 (C.A.C.)
| | - Carol A. Carter
- Department of Microbiology & Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794-5222, USA;
- Correspondence: (N.T.); (C.A.C.); Tel.: +1-631-632-8801 (C.A.C.)
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