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Gilleron J, Chafik A, Lacas-Gervais S, Tanti JF, Cormont M. Golgi-associated retrograde protein (GARP) complex-dependent endosomes to trans Golgi network retrograde trafficking is controlled by Rab4b. Cell Mol Biol Lett 2024; 29:54. [PMID: 38627612 PMCID: PMC11020649 DOI: 10.1186/s11658-024-00574-w] [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: 12/18/2023] [Accepted: 04/05/2024] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND The trafficking of cargoes from endosomes to the trans-Golgi network requires numerous sequential and coordinated steps. Cargoes are sorted into endosomal-derived carriers that are transported, tethered, and fused to the trans-Golgi network. The tethering step requires several complexes, including the Golgi-associated retrograde protein complex, whose localization at the trans-Golgi network is determined by the activity of small GTPases of the Arl and Rab family. However, how the Golgi-associated retrograde protein complex recognizes the endosome-derived carriers that will fuse with the trans-Golgi network is still unknown. METHODS We studied the retrograde trafficking to the trans-Golgi network by using fluorescent cargoes in cells overexpressing Rab4b or after Rab4b knocked-down by small interfering RNA in combination with the downregulation of subunits of the Golgi-associated retrograde protein complex. We used immunofluorescence and image processing (Super Resolution Radial Fluctuation and 3D reconstruction) as well as biochemical approaches to characterize the consequences of these interventions on cargo carriers trafficking. RESULTS We reported that the VPS52 subunit of the Golgi-associated retrograde protein complex is an effector of Rab4b. We found that overexpression of wild type or active Rab4b increased early endosomal to trans-Golgi network retrograde trafficking of the cation-independent mannose-6-phosphate receptor in a Golgi-associated retrograde protein complex-dependent manner. Conversely, overexpression of an inactive Rab4b or Rab4b knockdown attenuated this trafficking. In the absence of Rab4b, the internalized cation-independent mannose 6 phosphate receptor did not have access to VPS52-labeled structures that look like endosomal subdomains and/or endosome-derived carriers, and whose subcellular distribution is Rab4b-independent. Consequently, the cation-independent mannose-6-phosphate receptor was blocked in early endosomes and no longer had access to the trans-Golgi network. CONCLUSION Our results support that Rab4b, by controlling the sorting of the cation-independent mannose-6-phosphate receptor towards VPS52 microdomains, confers a directional specificity for cargo carriers en route to the trans-Golgi network. Given the importance of the endocytic recycling in cell homeostasis, disruption of the Rab4b/Golgi-associated retrograde protein complex-dependent step could have serious consequences in pathologies.
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Affiliation(s)
- Jérôme Gilleron
- Université Côte d'Azur, INSERM, Mediterranean Center of Molecular Medicine (C3M), Team "Insulin Resistance in Obesity and Type 2 Diabetes", Bâtiment Archimed, 151 Route de Saint Antoine de Ginestière, BP 2 3194, 06200, Nice Cedex 03, France.
| | - Abderrahman Chafik
- Université Côte d'Azur, INSERM, Mediterranean Center of Molecular Medicine (C3M), Team "Insulin Resistance in Obesity and Type 2 Diabetes", Bâtiment Archimed, 151 Route de Saint Antoine de Ginestière, BP 2 3194, 06200, Nice Cedex 03, France
| | - Sandra Lacas-Gervais
- Université Côte d'Azur, CCMA, Centre Commun de Microscopie Appliquée (CCMA), Nice, France
| | - Jean-François Tanti
- Université Côte d'Azur, INSERM, Mediterranean Center of Molecular Medicine (C3M), Team "Insulin Resistance in Obesity and Type 2 Diabetes", Bâtiment Archimed, 151 Route de Saint Antoine de Ginestière, BP 2 3194, 06200, Nice Cedex 03, France
| | - Mireille Cormont
- Université Côte d'Azur, INSERM, Mediterranean Center of Molecular Medicine (C3M), Team "Insulin Resistance in Obesity and Type 2 Diabetes", Bâtiment Archimed, 151 Route de Saint Antoine de Ginestière, BP 2 3194, 06200, Nice Cedex 03, France.
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Lisboa J, Pereira C, Pinto RD, Rodrigues IS, Pereira LMG, Pinheiro B, Oliveira P, Pereira PJB, Azevedo JE, Durand D, Benz R, do Vale A, Dos Santos NMS. Unconventional structure and mechanisms for membrane interaction and translocation of the NF-κB-targeting toxin AIP56. Nat Commun 2023; 14:7431. [PMID: 37973928 PMCID: PMC10654918 DOI: 10.1038/s41467-023-43054-z] [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: 05/15/2023] [Accepted: 10/30/2023] [Indexed: 11/19/2023] Open
Abstract
Bacterial AB toxins are secreted key virulence factors that are internalized by target cells through receptor-mediated endocytosis, translocating their enzymatic domain to the cytosol from endosomes (short-trip) or the endoplasmic reticulum (long-trip). To accomplish this, bacterial AB toxins evolved a multidomain structure organized into either a single polypeptide chain or non-covalently associated polypeptide chains. The prototypical short-trip single-chain toxin is characterized by a receptor-binding domain that confers cellular specificity and a translocation domain responsible for pore formation whereby the catalytic domain translocates to the cytosol in an endosomal acidification-dependent way. In this work, the determination of the three-dimensional structure of AIP56 shows that, instead of a two-domain organization suggested by previous studies, AIP56 has three-domains: a non-LEE encoded effector C (NleC)-like catalytic domain associated with a small middle domain that contains the linker-peptide, followed by the receptor-binding domain. In contrast to prototypical single-chain AB toxins, AIP56 does not comprise a typical structurally complex translocation domain; instead, the elements involved in translocation are scattered across its domains. Thus, the catalytic domain contains a helical hairpin that serves as a molecular switch for triggering the conformational changes necessary for membrane insertion only upon endosomal acidification, whereas the middle and receptor-binding domains are required for pore formation.
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Affiliation(s)
- Johnny Lisboa
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal.
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal.
| | - Cassilda Pereira
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Rute D Pinto
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
| | - Inês S Rodrigues
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Liliana M G Pereira
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
| | - Bruno Pinheiro
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
- Doctoral Program in Molecular and Cell Biology (MCbiology), Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto, Porto, Portugal
| | - Pedro Oliveira
- EPIUnit, ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Pedro José Barbosa Pereira
- Biomolecular Structure Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Macromolecular Structure Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Jorge E Azevedo
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
- Organelle Biogenesis and Function, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Organelle Biogenesis and Function, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Dominique Durand
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Roland Benz
- Science Faculty, Constructor University, Bremen, Germany
| | - Ana do Vale
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Nuno M S Dos Santos
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal.
- Fish Immunology and Vaccinology Group, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal.
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Feng X, Chang R, Zhu H, Yang Y, Ji Y, Liu D, Qin H, Yin J, Rong H. Engineering Proteins for Cell Entry. Mol Pharm 2023; 20:4868-4882. [PMID: 37708383 DOI: 10.1021/acs.molpharmaceut.3c00467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Proteins are essential for life, as they participate in all vital processes in the body. In the past decade, delivery of active proteins to specific cells and organs has attracted increasing interest. However, most proteins cannot enter the cytoplasm due to the cell membrane acting as a natural barrier. To overcome this challenge, various proteins have been engineered to acquire cell-penetrating capacity by mimicking or modifying natural shuttling proteins. In this review, we provide an overview of the different types of engineered cell-penetrating proteins such as cell-penetrating peptides, supercharged proteins, receptor-binding proteins, and bacterial toxins. We also discuss some strategies for improving endosomal escape such as pore formation, the proton sponge effect, and hijacking intracellular trafficking pathways. Finally, we introduce some novel methods and technologies for designing and detecting engineered cell-penetrating proteins.
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Affiliation(s)
- Xiaoyu Feng
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Ruilong Chang
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Haichao Zhu
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Yifan Yang
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Yue Ji
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Dingkang Liu
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Hai Qin
- Department of Clinical Laboratory, Beijing Jishuitan Hospital Guizhou Hospital, No. 206, Sixian Street, Baiyun District, Guiyang, Guizhou 550014, China
| | - Jun Yin
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals and State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Haibo Rong
- Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing 210009, China
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Liu X, Tan Q, Wen J, Wang X, Yang G, Li Y, Lu M, Ye W, Si A, Ma S, Ding T, Sun L, Liu F, Zhang M, Jiang T, Gao W. Improving the cytotoxicity of immunotoxins by reducing the affinity of the antibody in acidic pH. J Transl Med 2023; 21:572. [PMID: 37626430 PMCID: PMC10463491 DOI: 10.1186/s12967-023-04210-7] [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: 12/24/2022] [Accepted: 05/19/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND Immunotoxins are antibody-toxin conjugates that bind to surface antigens and exert effective cytotoxic activity after internalization into tumor cells. Immunotoxins exhibit effective cytotoxicity and have been approved by the FDA to treat multiple hematological malignancies, such as hairy cell leukemia and cutaneous T-cell lymphoma. However, most of the internalized immunotoxin is degraded in lysosomes, and only approximately 5% of free toxin escapes into the cytosol to exert cytotoxicity. Many studies have improved immunotoxins by engineering the toxin fragment to reduce immunogenicity or increase stability, but how the antibody fragment contributes to the activity of immunotoxins has not been well demonstrated. METHODS In the current study, we used 32A9 and 42A1, two anti-GPC3 antibodies with similar antigen-binding capabilities and internalization rates, to construct scFv-mPE24 immunotoxins and evaluated their in vitro and in vivo antitumor activities. Next, the antigen-binding capacity, trafficking, intracellular protein stability and release of free toxin of 32A9 scFv-mPE24 and 42A1 scFv-mPE24 were compared to elucidate their different antitumor activities. Furthermore, we used a lysosome inhibitor to evaluate the degradation behavior of 32A9 scFv-mPE24 and 42A1 scFv-mPE24. Finally, the antigen-binding patterns of 32A9 and 42A1 were compared under neutral and acidic pH conditions. RESULTS Although 32A9 and 42A1 had similar antigen binding capacities and internalization rates, 32A9 scFv-mPE24 had superior antitumor activity compared to 42A1 scFv-mPE24. We found that 32A9 scFv-mPE24 exhibited faster degradation and drove efficient free toxin release compared to 42A1 scFv-mPE24. These phenomena were determined by the different degradation behaviors of 32A9 scFv-mPE24 and 42A1 scFv-mPE24 in lysosomes. Moreover, 32A9 was sensitive to the low-pH environment, which made the 32A9 conjugate easily lose antigen binding and undergo degradation in lysosomes, and the free toxin was then efficiently produced to exert cytotoxicity, whereas 42A1 was resistant to the acidic environment, which kept the 42A1 conjugate relatively stable in lysosomes and delayed the release of free toxin. CONCLUSIONS These results showed that a low pH-sensitive antibody-based immunotoxin degraded faster in lysosomes, caused effective free toxin release, and led to improved cytotoxicity compared to an immunotoxin based on a normal antibody. Our findings suggested that a low pH-sensitive antibody might have an advantage in the design of immunotoxins and other lysosomal degradation-dependent antibody conjugate drugs.
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Affiliation(s)
- Xiaoyu Liu
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Qingqing Tan
- Department of Gynecology Oncology, Changzhou Maternal and Child Health Care Hospital, Changzhou Medical Center, Nanjing Medical University, Changzhou, China
| | - Jiaqi Wen
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Xufei Wang
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Gang Yang
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Yuxiao Li
- Department of Endocrinology, The First Affiliated Hospital With Nanjing Medical University, Nanjing, China
| | - Ming Lu
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Wei Ye
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Anfeng Si
- Department of Surgical Oncology, Jinling Hospital, Medical School of Nanjing University, 34 Yanggongjing Road, Nanjing, 210000, Jiangsu, People's Republic of China
| | - Sujuan Ma
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Tong Ding
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Luan Sun
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Fang Liu
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China
| | - Mei Zhang
- Department of Endocrinology, The First Affiliated Hospital With Nanjing Medical University, Nanjing, China
| | - Tao Jiang
- Department of Surgical Oncology, Jinling Hospital, Medical School of Nanjing University, 34 Yanggongjing Road, Nanjing, 210000, Jiangsu, People's Republic of China.
| | - Wei Gao
- School of Basic Medical Sciences and Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Personalized Cancer Medicine, Nanjing Medical University, 101 Longmian Road, Xuehai Building, Nanjing, 211166, Jiangsu, People's Republic of China.
- The Affiliated Changzhou Second People's Hospital of Nanjing Medical University, Changzhou Second People's Hospital, Changzhou Medical Center, Nanjing Medical University, Changzhou, China.
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Qiu C, Xia F, Zhang J, Shi Q, Meng Y, Wang C, Pang H, Gu L, Xu C, Guo Q, Wang J. Advanced Strategies for Overcoming Endosomal/Lysosomal Barrier in Nanodrug Delivery. RESEARCH (WASHINGTON, D.C.) 2023; 6:0148. [PMID: 37250954 PMCID: PMC10208951 DOI: 10.34133/research.0148] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/27/2023] [Indexed: 05/31/2023]
Abstract
Nanocarriers have therapeutic potential to facilitate drug delivery, including biological agents, small-molecule drugs, and nucleic acids. However, their efficiency is limited by several factors; among which, endosomal/lysosomal degradation after endocytosis is the most important. This review summarizes advanced strategies for overcoming endosomal/lysosomal barriers to efficient nanodrug delivery based on the perspective of cellular uptake and intracellular transport mechanisms. These strategies include promoting endosomal/lysosomal escape, using non-endocytic methods of delivery to directly cross the cell membrane to evade endosomes/lysosomes and making a detour pathway to evade endosomes/lysosomes. On the basis of the findings of this review, we proposed several promising strategies for overcoming endosomal/lysosomal barriers through the smarter and more efficient design of nanodrug delivery systems for future clinical applications.
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Affiliation(s)
- Chong Qiu
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Fei Xia
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Junzhe Zhang
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Qiaoli Shi
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Yuqing Meng
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Chen Wang
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Huanhuan Pang
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Liwei Gu
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Chengchao Xu
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Qiuyan Guo
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Jigang Wang
- Artemisinin Research Center, and Institute of Chinese Materia Medica,
China Academy of Chinese Medical Sciences, Beijing 100700, China
- Department of Nephrology, and Shenzhen Clinical Research Centre for Geriatrics, Shenzhen People's Hospital, The First Affiliated Hospital,
Southern University of Science and Technology, Shenzhen, Guangdong 518020, China
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Parenteral Exposure of Mice to Ricin Toxin Induces Fatal Hypoglycemia by Cytokine-Mediated Suppression of Hepatic Glucose-6-Phosphatase Expression. Toxins (Basel) 2022; 14:toxins14120820. [PMID: 36548717 PMCID: PMC9786807 DOI: 10.3390/toxins14120820] [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: 10/18/2022] [Revised: 11/08/2022] [Accepted: 11/14/2022] [Indexed: 11/25/2022] Open
Abstract
Ricin toxin is an agent of biodefense concern and we have been developing countermeasures for ricin threats. In doing so, we sought biomarkers of ricin toxicosis and found that in mice parenteral injection of ricin toxin causes profound hypoglycemia, in the absence of other clinical laboratory abnormalities. We now seek to identify the mechanisms underlying this hypoglycemia. Within the first hours following injection, while still normoglycemic, lymphopenia and pro-inflammatory cytokine secretion were observed, particularly tumor necrosis factor (TNF)-α. The cytokine response evolved over the next day into a complex storm of both pro- and anti-inflammatory cytokines. Evaluation of pancreatic function and histology demonstrated marked islet hypertrophy involving predominantly β-cells, but only mildly elevated levels of insulin secretion, and diminished hepatic insulin signaling. Drops in blood glucose were observed even after destruction of β-cells with streptozotocin. In the liver, we observed a rapid and persistent decrease in the expression of glucose-6-phosphatase (G6Pase) RNA and protein levels, accompanied by a drop in glucose-6-phosphate and increase in glycogen. TNF-α has previously been reported to suppress G6Pase expression. In humans, a genetic deficiency of G6Pase results in glycogen storage disease, type-I (GSD-1), a hallmark of which is potentially fatal hypoglycemia.
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Kempa J, O’Shea-Stone G, Moss CE, Peters T, Marcotte TK, Tripet B, Eilers B, Bothner B, Copié V, Pincus SH. Distinct Metabolic States Are Observed in Hypoglycemia Induced in Mice by Ricin Toxin or by Fasting. Toxins (Basel) 2022; 14:toxins14120815. [PMID: 36548712 PMCID: PMC9782143 DOI: 10.3390/toxins14120815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/08/2022] [Accepted: 11/15/2022] [Indexed: 11/23/2022] Open
Abstract
Hypoglycemia may be induced by a variety of physiologic and pathologic stimuli and can result in life-threatening consequences if untreated. However, hypoglycemia may also play a role in the purported health benefits of intermittent fasting and caloric restriction. Previously, we demonstrated that systemic administration of ricin toxin induced fatal hypoglycemia in mice. Here, we examine the metabolic landscape of the hypoglycemic state induced in the liver of mice by two different stimuli: systemic ricin administration and fasting. Each stimulus produced the same decrease in blood glucose and weight loss. The polar metabolome was studied using 1H NMR, quantifying 59 specific metabolites, and untargeted LC-MS on approximately 5000 features. Results were analyzed by multivariate analyses, using both principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA), to identify global metabolic patterns, and by univariate analyses (ANOVA) to assess individual metabolites. The results demonstrated that while there were some similarities in the responses to the two stimuli including decreased glucose, ADP, and glutathione, they elicited distinct metabolic states. The metabolite showing the greatest difference was O-phosphocholine, elevated in ricin-treated animals and known to be affected by the pro-inflammatory cytokine TNF-α. Another difference was the alternative fuel source utilized, with fasting-induced hypoglycemia primarily ketotic, while the response to ricin-induced hypoglycemia involves protein and amino acid catabolism.
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Affiliation(s)
- Jacob Kempa
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Galen O’Shea-Stone
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Corinne E. Moss
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Tami Peters
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Tamera K. Marcotte
- Animal Resources Center, Montana State University, Bozeman, MT 59717, USA
| | - Brian Tripet
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Brian Eilers
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Valérie Copié
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
- Correspondence: (V.C.); (S.H.P.)
| | - Seth H. Pincus
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
- Correspondence: (V.C.); (S.H.P.)
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Human Cytomegalovirus Manipulates Syntaxin 6 for Successful Trafficking and Subsequent Infection of Monocytes. J Virol 2022; 96:e0081922. [PMID: 35862696 PMCID: PMC9327712 DOI: 10.1128/jvi.00819-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Human cytomegalovirus (HCMV) exhibits a complex host-pathogen interaction with peripheral blood monocytes. We have identified a unique, cell-type specific retrograde-like intracellular trafficking pattern that HCMV utilizes to gain access to the monocyte nucleus and for productive infection. We show that infection of primary human monocytes, epithelial cells, and fibroblasts leads to an increase in the amount of the trafficking protein Syntaxin 6 (Stx6). However, only knockdown (KD) of Stx6 in monocytes inhibited viral trafficking to the trans-Golgi network (TGN), a requisite step for nuclear translocation in monocytes. Conversely, KD of Stx6 in epithelial cells and fibroblasts did not change the kinetics of nuclear translocation and productive infection. Stx6 predominantly functions at the level of the TGN where it facilitates retrograde transport, a trafficking pathway used by only a few cellular proteins and seldom by pathogens. We also newly identify that in monocytes, Stx6 exhibits an irregular vesicular localization rather than being concentrated at the TGN as seen in other cell-types. Lastly, we implicate that viral particles that associate with both Stx6 and EEA1 early in infection are the viral population that successfully traffics to the TGN at later time points and undergo nuclear translocation. Additionally, we show for the first time that HCMV enters the TGN, and that lack of Stx6 prevents viral trafficking to this organelle. We argue that we have identified an essential cell-type specific regulator that controls early steps in efficient productive infection of a cell-type required for viral persistence and disease. IMPORTANCE Human cytomegalovirus (HCMV) infection causes severe and often fatal disease in the immunocompromised. It is one of the leading infectious causes of birth defects and causes severe complications in transplant recipients. By uncovering the unique pathways used by the virus to infect key cells, such as monocytes, responsible for dissemination and persistence, we provide new potential targets for therapeutic intervention.
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9
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STxB as an Antigen Delivery Tool for Mucosal Vaccination. Toxins (Basel) 2022; 14:toxins14030202. [PMID: 35324699 PMCID: PMC8948715 DOI: 10.3390/toxins14030202] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 12/31/2022] Open
Abstract
Immunotherapy against cancer and infectious disease holds the promise of high efficacy with minor side effects. Mucosal vaccines to protect against tumors or infections disease agents that affect the upper airways or the lung are still lacking, however. One mucosal vaccine candidate is the B-subunit of Shiga toxin, STxB. In this review, we compare STxB to other immunotherapy vectors. STxB is a non-toxic protein that binds to a glycosylated lipid, termed globotriaosylceramide (Gb3), which is preferentially expressed by dendritic cells. We review the use of STxB for the cross-presentation of tumor or viral antigens in a MHC class I-restricted manner to induce humoral immunity against these antigens in addition to polyfunctional and persistent CD4+ and CD8+ T lymphocytes capable of protecting against viral infection or tumor growth. Other literature will be summarized that documents a powerful induction of mucosal IgA and resident memory CD8+ T cells against mucosal tumors specifically when STxB-antigen conjugates are administered via the nasal route. It will also be pointed out how STxB-based vaccines have been shown in preclinical cancer models to synergize with other therapeutic modalities (immune checkpoint inhibitors, anti-angiogenic therapy, radiotherapy). Finally, we will discuss how molecular aspects such as low immunogenicity, cross-species conservation of Gb3 expression, and lack of toxicity contribute to the competitive positioning of STxB among the different DC targeting approaches. STxB thereby appears as an original and innovative tool for the development of mucosal vaccines in infectious diseases and cancer.
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10
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Abstract
Biomolecules such as peptides, proteins, and nucleic acids generally cannot cross a cell membrane by passive diffusion. Nevertheless, cell-penetrating peptides (CPPs), bacterial protein toxins, certain eukaryotic proteins, viruses, and many synthetic drug delivery vehicles have been shown to enter the cytosol of eukaryotic cells with varying efficiencies. They generally enter the cell by one or more of the endocytic mechanisms and are initially localized inside the endosomes. But how they cross the endosomal membrane to reach the cytosol (i.e., endosomal escape) has been a mystery for decades, and this knowledge gap has been a major bottleneck for the development of efficient drug delivery systems. In addition, many bacterial and eukaryotic proteins are transported across the plasma membrane in their native states into the periplasmic/extracellular space through the twin-arginine translocation (TAT) and unconventional protein secretion (UPS) systems, respectively. Again, the mechanisms underpinning these protein export systems remain unclear.In this Account, I introduce a previously unrecognized, fundamental membrane translocation mechanism which we have termed the vesicle budding-and-collapse (VBC) mechanism. Through VBC, biomolecules of diverse sizes and physicochemical properties autonomously translocate across cell membranes topologically (i.e., from one side to the other side of the membrane) but not physically (i.e., without going through the membrane). We have demonstrated that CPPs and bacterial protein toxins escape the endosome by the VBC mechanism in giant unilamellar vesicles as well as live mammalian cells. This advance resulted from studies in which we labeled the biomolecules with a pH-sensitive, red-colored dye (pHAb) and phosphatidylserine with a pH-insensitive green dye (TopFluor) and monitored the intracellular trafficking of the biomolecules in real time by confocal microscopy. In addition, by enlarging the endosomes with a kinase inhibitor, we were able to visualize the structural changes of the endosomes (i.e., endosomal escape intermediates) as they went through the VBC process. I postulate that bacterial/viral/eukaryotic proteins, nonenveloped viruses, and synthetic drug delivery vehicles (e.g., polyplexes, lipoplexes, and lipid nanoparticles) may also escape the endosome by inducing VBC. Furthermore, I propose that VBC may be the mechanism that drives the bacterial TAT and eukaryotic UPS systems. Our findings fill a long-standing gap in cell biology and provide guiding principles for designing more efficient drug delivery vehicles.
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Affiliation(s)
- Dehua Pei
- Corresponding Author: To whom correspondence should be addressed: Dehua Pei. Department of Chemistry and Biochemistry and Ohio State Biochemistry Program, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio 43210, United States; (+1-614-688-4068, )
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11
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Van de Vyver T, De Smedt SC, Raemdonck K. Modulating intracellular pathways to improve non-viral delivery of RNA therapeutics. Adv Drug Deliv Rev 2022; 181:114041. [PMID: 34763002 DOI: 10.1016/j.addr.2021.114041] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/12/2021] [Accepted: 11/02/2021] [Indexed: 12/12/2022]
Abstract
RNA therapeutics (e.g. siRNA, oligonucleotides, mRNA, etc.) show great potential for the treatment of a myriad of diseases. However, to reach their site of action in the cytosol or nucleus of target cells, multiple intra- and extracellular barriers have to be surmounted. Several non-viral delivery systems, such as nanoparticles and conjugates, have been successfully developed to meet this requirement. Unfortunately, despite these clear advances, state-of-the-art delivery agents still suffer from relatively low intracellular delivery efficiencies. Notably, our current understanding of the intracellular delivery process is largely oversimplified. Gaining mechanistic insight into how RNA formulations are processed by cells will fuel rational design of the next generation of delivery carriers. In addition, identifying which intracellular pathways contribute to productive RNA delivery could provide opportunities to boost the delivery performance of existing nanoformulations. In this review, we discuss both established as well as emerging techniques that can be used to assess the impact of different intracellular barriers on RNA transfection performance. Next, we highlight how several modulators, including small molecules but also genetic perturbation technologies, can boost RNA delivery by intervening at differing stages of the intracellular delivery process, such as cellular uptake, intracellular trafficking, endosomal escape, autophagy and exocytosis.
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Affiliation(s)
- Thijs Van de Vyver
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
| | - Stefaan C De Smedt
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
| | - Koen Raemdonck
- Ghent Research Group on Nanomedicines, Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium.
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12
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Jia X, Zhang Y, Wang T, Fu Y. Highly Efficient Method for Intracellular Delivery of Proteins Mediated by Cholera Toxin-Induced Protein Internalization. Mol Pharm 2021; 18:4067-4078. [PMID: 34672633 DOI: 10.1021/acs.molpharmaceut.1c00479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Delivery of functional proteins into cells may help us understand how specific protein influences cell behavior as well as treat diseases caused by protein deficiency or loss-of-function mutations. However, protein cannot enter cells by diffusion. In this work, a novel cell biology tool for delivering recombinant proteins into mammalian cells was developed. We hijacked the intracellular transport routes used by the cholera toxin and took advantage of recent development on split intein that is compatible with denatured conditions and shows an exceptional splicing activity to deliver a protein of interest into mammalian cells. Here, we used green fluorescent protein and apoptin as proofs-of-concept. The results demonstrate that the cholera toxin B subunit alone could deliver other recombinant proteins into cells through either covalent conjugation or noncovalent interaction. Our method offers more than 10-fold better delivery efficiency than the tat cell-penetrating peptide and is selective for ganglioside-rich cells. This study adds a useful tool to the receptor-mediated intracellular targeting toolkit and opens possibility for the selective delivery of therapeutic proteins into ganglioside-rich cells.
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Affiliation(s)
- Xiaofan Jia
- Department of Pharmacology, Tianjin Key Laboratory of Inflammatory Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Yan Zhang
- Department of Pharmacology, Tianjin Key Laboratory of Inflammatory Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Ting Wang
- Department of Pharmacology, Tianjin Key Laboratory of Inflammatory Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Yuan Fu
- Department of Pharmacology, Tianjin Key Laboratory of Inflammatory Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
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13
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Borghesan E, Smith EP, Myeni S, Binder K, Knodler LA, Celli J. A Brucella effector modulates the Arf6-Rab8a GTPase cascade to promote intravacuolar replication. EMBO J 2021; 40:e107664. [PMID: 34423453 PMCID: PMC8488576 DOI: 10.15252/embj.2021107664] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 07/26/2021] [Accepted: 07/30/2021] [Indexed: 01/15/2023] Open
Abstract
Remodeling of host cellular membrane transport pathways is a common pathogenic trait of many intracellular microbes that is essential to their intravacuolar life cycle and proliferation. The bacterium Brucella abortus generates a host endoplasmic reticulum‐derived vacuole (rBCV) that supports its intracellular growth, via VirB Type IV secretion system‐mediated delivery of effector proteins, whose functions and mode of action are mostly unknown. Here, we show that the effector BspF specifically promotes Brucella replication within rBCVs by interfering with vesicular transport between the trans‐Golgi network (TGN) and recycling endocytic compartment. BspF targeted the recycling endosome, inhibited retrograde traffic to the TGN, and interacted with the Arf6 GTPase‐activating Protein (GAP) ACAP1 to dysregulate Arf6‐/Rab8a‐dependent transport within the recycling endosome, which resulted in accretion of TGN‐associated vesicles by rBCVs and enhanced bacterial growth. Altogether, these findings provide mechanistic insight into bacterial modulation of membrane transport used to promote their own proliferation within intracellular vacuoles.
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Affiliation(s)
- Elizabeth Borghesan
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA, USA
| | - Erin P Smith
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA, USA
| | - Sebenzile Myeni
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Kelsey Binder
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Leigh A Knodler
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA, USA
| | - Jean Celli
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA, USA.,Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
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14
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Bozzer S, Bo MD, Toffoli G, Macor P, Capolla S. Nanoparticles-Based Oligonucleotides Delivery in Cancer: Role of Zebrafish as Animal Model. Pharmaceutics 2021; 13:1106. [PMID: 34452067 PMCID: PMC8400075 DOI: 10.3390/pharmaceutics13081106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/16/2021] [Accepted: 07/18/2021] [Indexed: 12/29/2022] Open
Abstract
Oligonucleotide (ON) therapeutics are molecular target agents composed of chemically synthesized DNA or RNA molecules capable of inhibiting gene expression or protein function. How ON therapeutics can efficiently reach the inside of target cells remains a problem still to be solved in the majority of potential clinical applications. The chemical structure of ON compounds could affect their capability to pass through the plasma membrane. Other key factors are nuclease degradation in the extracellular space, renal clearance, reticulo-endothelial system, and at the target cell level, the endolysosomal system and the possible export via exocytosis. Several delivery platforms have been proposed to overcome these limits including the use of lipidic, polymeric, and inorganic nanoparticles, or hybrids between them. The possibility of evaluating the efficacy of the proposed therapeutic strategies in useful in vivo models is still a pivotal need, and the employment of zebrafish (ZF) models could expand the range of possibilities. In this review, we briefly describe the main ON therapeutics proposed for anticancer treatment, and the different strategies employed for their delivery to cancer cells. The principal features of ZF models and the pros and cons of their employment in the development of ON-based therapeutic strategies are also discussed.
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Affiliation(s)
- Sara Bozzer
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy;
| | - Michele Dal Bo
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, 33081 Aviano, Italy; (M.D.B.); (G.T.); (S.C.)
| | - Giuseppe Toffoli
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, 33081 Aviano, Italy; (M.D.B.); (G.T.); (S.C.)
| | - Paolo Macor
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy;
| | - Sara Capolla
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, 33081 Aviano, Italy; (M.D.B.); (G.T.); (S.C.)
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15
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Liang XH, Nichols JG, De Hoyos CL, Sun H, Zhang L, Crooke ST. Golgi-58K can re-localize to late endosomes upon cellular uptake of PS-ASOs and facilitates endosomal release of ASOs. Nucleic Acids Res 2021; 49:8277-8293. [PMID: 34244781 PMCID: PMC8373082 DOI: 10.1093/nar/gkab599] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/21/2021] [Accepted: 06/29/2021] [Indexed: 11/14/2022] Open
Abstract
Phosphorothioate (PS) modified antisense oligonucleotide (ASO) drugs can trigger RNase H1 cleavage of cellular target RNAs to modulate gene expression. Internalized PS-ASOs must be released from membraned endosomal organelles, a rate limiting step that is not well understood. Recently we found that M6PR transport between Golgi and late endosomes facilitates productive release of PS-ASOs, raising the possibility that Golgi-mediated transport may play important roles in PS-ASO activity. Here we further evaluated the involvement of Golgi in PS-ASO activity by examining additional Golgi proteins. Reduction of certain Golgi proteins, including Golgi-58K, GCC1 and TGN46, decreased PS-ASO activity, without substantial effects on Golgi integrity. Upon PS-ASO cellular uptake, Golgi-58K was recruited to late endosomes where it colocalized with PS-ASOs. Reduction of Golgi-58K caused slower PS-ASO release from late endosomes, decreased GCC2 late endosome relocalization, and led to slower retrograde transport of M6PR from late endosomes to trans-Golgi. Late endosome relocalization of Golgi-58K requires Hsc70, and is most likely mediated by PS-ASO-protein interactions. Together, these results suggest a novel function of Golgi-58K in mediating Golgi-endosome transport and indicate that the Golgi apparatus plays an important role in endosomal release of PS-ASO, ensuring antisense activity.
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Affiliation(s)
| | | | | | - Hong Sun
- Antisense Drug Discovery, Ionis Pharmaceuticals, Inc., Carlsbad, CA 92010, USA
| | - Lingdi Zhang
- Core Antisense Research, Carlsbad, CA 92010, USA
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16
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The Protein Toxins Ricin and Shiga Toxin as Tools to Explore Cellular Mechanisms of Internalization and Intracellular Transport. Toxins (Basel) 2021; 13:toxins13060377. [PMID: 34070659 PMCID: PMC8227415 DOI: 10.3390/toxins13060377] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/12/2021] [Accepted: 05/22/2021] [Indexed: 12/18/2022] Open
Abstract
Protein toxins secreted by bacteria and found in plants can be threats to human health. However, their extreme toxicity can also be exploited in different ways, e.g., to produce hybrid toxins directed against cancer cells and to study transport mechanisms in cells. Investigations during the last decades have shown how powerful these molecules are as tools in cell biological research. Here, we first present a partly historical overview, with emphasis on Shiga toxin and ricin, of how such toxins have been used to characterize processes and proteins of importance for their trafficking. In the second half of the article, we describe how one can now use toxins to investigate the role of lipid classes for intracellular transport. In recent years, it has become possible to quantify hundreds of lipid species using mass spectrometry analysis. Thus, it is also now possible to explore the importance of lipid species in intracellular transport. The detailed analyses of changes in lipids seen under conditions of inhibited toxin transport reveal previously unknown connections between syntheses of lipid classes and demonstrate the ability of cells to compensate under given conditions.
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17
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Liu Y, Tian S, Thaker H, Dong M. Shiga Toxins: An Update on Host Factors and Biomedical Applications. Toxins (Basel) 2021; 13:222. [PMID: 33803852 PMCID: PMC8003205 DOI: 10.3390/toxins13030222] [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: 02/18/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 12/18/2022] Open
Abstract
Shiga toxins (Stxs) are classic bacterial toxins and major virulence factors of toxigenic Shigella dysenteriae and enterohemorrhagic Escherichia coli (EHEC). These toxins recognize a glycosphingolipid globotriaosylceramide (Gb3/CD77) as their receptor and inhibit protein synthesis in cells by cleaving 28S ribosomal RNA. They are the major cause of life-threatening complications such as hemolytic uremic syndrome (HUS), associated with severe cases of EHEC infection, which is the leading cause of acute kidney injury in children. The threat of Stxs is exacerbated by the lack of toxin inhibitors and effective treatment for HUS. Here, we briefly summarize the Stx structure, subtypes, in vitro and in vivo models, Gb3 expression and HUS, and then introduce recent studies using CRISPR-Cas9-mediated genome-wide screens to identify the host cell factors required for Stx action. We also summarize the latest progress in utilizing and engineering Stx components for biomedical applications.
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Affiliation(s)
- Yang Liu
- Department of Nephrology, The First Hospital of Jilin University, Changchun 130021, China
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Songhai Tian
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Hatim Thaker
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Min Dong
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (H.T.)
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
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18
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Tsjokajev A, Røberg-Larsen H, Wilson SR, Dyve Lingelem AB, Skotland T, Sandvig K, Lundanes E. Mass spectrometry-based measurements of cyclic adenosine monophosphate in cells, simplified using reversed phase liquid chromatography with a polar characterized stationary phase. J Chromatogr B Analyt Technol Biomed Life Sci 2020; 1160:122384. [PMID: 32971370 DOI: 10.1016/j.jchromb.2020.122384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 10/23/2022]
Abstract
3', 5' - Cyclic adenosine monophosphate (cAMP) is a ubiquitous second messenger that is involved in many cellular functions and biological processes. In several cell types, cholera toxin will increase the level of cAMP, which mediates toxic effects on cells. In this context, we have developed a fast and simple method based on extraction with 5% trichloroacetic acid (TCA) and quantitation with liquid chromatography-mass tandem spectrometry (LC-MS/MS) for measuring cAMP in cells. A main feature of the LC-MS method was employing a reversed phase C18 column (2.1 mm × 50 mm, 1.6 µm particles) compatible with a 100% aqueous mobile phase, providing retention of the highly polar analyte. Isocratic separations allowed for fast subsequent injections. Negative mode electrospray ionization detection was performed with a triple quadrupole (QqQ)MS. cAMP was extracted from cell samples (~106 cells per well) and spiked with a labelled internal standard, using 200 µL of 5% TCA. The extraction solvent was fully compatible for direct injection onto the reversed phase column. After 10 min incubation, the supernatant was removed, and 10 µL of the supernatant was directly analysed by LC-MS. The method was characterized by the simplicity of the extraction, and the speed (3 min retention time of cAMP), sensitivity (250 pg/mL detection limit), and selectivity (separation from interferences e.g. isomeric compounds) of the LC-MS method, and could be used for quantitation of cAMP in the range 1-500 ng/mL cell extract.
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Affiliation(s)
- Ahmad Tsjokajev
- Department of Chemistry, University of Oslo, Post Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Hanne Røberg-Larsen
- Department of Chemistry, University of Oslo, Post Box 1033, Blindern, NO-0315 Oslo, Norway
| | - Steven Ray Wilson
- Department of Chemistry, University of Oslo, Post Box 1033, Blindern, NO-0315 Oslo, Norway; Hybrid Technology Hub-Centre of Excellence, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Anne-Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway
| | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway
| | - Elsa Lundanes
- Department of Chemistry, University of Oslo, Post Box 1033, Blindern, NO-0315 Oslo, Norway
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Bunkar N, Sharma J, Chouksey A, Kumari R, Gupta PK, Tiwari R, Lodhi L, Srivastava RK, Bhargava A, Mishra PK. Clostridium perfringens phospholipase C impairs innate immune response by inducing integrated stress response and mitochondrial-induced epigenetic modifications. Cell Signal 2020; 75:109776. [PMID: 32916276 DOI: 10.1016/j.cellsig.2020.109776] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/27/2020] [Accepted: 09/06/2020] [Indexed: 10/23/2022]
Abstract
Clostridium perfringens, a rod-shaped, gram-positive, anaerobic, spore-forming bacterium is one of the most widely occurring bacterial pathogens, associated with a spectrum of diseases in humans. A major virulence factor during its infection is the enzyme phospholipase C encoded by the plc gene, known as Clostridium perfringens phospholipase C (CpPLC). The present study was designed to understand the role of CpPLC in inducing survival mechanisms and mitochondrial-induced epigenetic changes in a human lymphocyte cell culture model. Following exposure to CpPLC, a significant generation of mitochondrial reactive oxygen species was observed, which coincided with the changes in the expression of vital components of MAP/ERK/RTK signaling cascade that regulates the downstream cellular functions. These disturbances further led to alterations in the mitochondrial genome and functioning. This was supported by the observed upregulation in the expression of mitochondrial fission genes Drp1, Fis1, and Mff, and mitochondrial fusion genes MFN1, MFN2, and OPA1 following CpPLC exposure. CpPLC exposed cells showed upregulation of OMA1, DELE1, and HRI genes involved in the integrated stress response (ISR), which suggests that it may induce the ISR that provides a pro-survival mechanism to the host cell. CpPLC also initiated immune patho-physiologic mechanisms including mitochondrial-induced epigenetic modifications through a mitochondrial-ROS driven signaling pathway. Interestingly, epigenetic machinery not only play a pivotal role in lymphocyte homeostasis by contributing to cell-fate decisions but thought to be one of the mechanisms by which intracellular pathogens survive within the host cells. Importantly, the impairment of mtDNA repair among the CpPLC exposed cells, induced alterations within mtDNA methylation, and led to the deregulation of MT-CO1, MT-ND6, MT-ATPase 6, and MT-ATPase8 gene expression profiles that are important for mitochondrial bioenergetics and subsequent metabolic pathways. This was further confirmed by the changes in the activity of mitochondrial electron chain complexes (complex I, II, III, IV and V). The altered mtDNA methylation profile was also found to be closely associated with the varied expression of mitomiRs and their targets. CpPLC exposed cells showed up-regulation of miR24 expression and down-regulation of miR34a, miR150, and miR155, while the increased expression of mitomiR target genes i.e. of K-Ras, MYC, EGFR, and NF-kβ was also observed in these cells. Altogether, our findings provide novel insights into the derailment of redox signaling machinery in CpPLC treated lymphocytes and its role in the induction of survival mechanisms and mitochondrial-induced epigenetic modifications.
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Affiliation(s)
- Neha Bunkar
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Jahnavi Sharma
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Anju Chouksey
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Roshani Kumari
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Pushpendra Kumar Gupta
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Rajnarayan Tiwari
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Lalit Lodhi
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | | | - Arpit Bhargava
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India
| | - Pradyumna Kumar Mishra
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
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Lingelem ABD, Kavaliauskiene S, Halsne R, Klokk TI, Surma MA, Klose C, Skotland T, Sandvig K. Diacylglycerol kinase and phospholipase D inhibitors alter the cellular lipidome and endosomal sorting towards the Golgi apparatus. Cell Mol Life Sci 2020; 78:985-1009. [PMID: 32447426 PMCID: PMC7897626 DOI: 10.1007/s00018-020-03551-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/12/2020] [Accepted: 05/13/2020] [Indexed: 12/13/2022]
Abstract
The membrane lipids diacylglycerol (DAG) and phosphatidic acid (PA) are important second messengers that can regulate membrane transport by recruiting proteins to the membrane and by altering biophysical membrane properties. DAG and PA are involved in the transport from the Golgi apparatus to endosomes, and we have here investigated whether changes in these lipids might be important for regulation of transport to the Golgi using the protein toxin ricin. Modulation of DAG and PA levels using DAG kinase (DGK) and phospholipase D (PLD) inhibitors gave a strong increase in retrograde ricin transport, but had little impact on ricin recycling or degradation. Inhibitor treatment strongly affected the endosome morphology, increasing endosomal tubulation and size. Furthermore, ricin was present in these tubular structures together with proteins known to regulate retrograde transport. Using siRNA to knock down different isoforms of PLD and DGK, we found that several isoforms of PLD and DGK are involved in regulating ricin transport to the Golgi. Finally, by performing lipidomic analysis we found that the DGK inhibitor gave a weak, but expected, increase in DAG levels, while the PLD inhibitor gave a strong and unexpected increase in DAG levels, showing that it is important to perform lipidomic analysis when using inhibitors of lipid metabolism.
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Affiliation(s)
- Anne Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Department of Forensic Biology, Oslo University Hospital, Oslo, Norway
| | - Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Ruth Halsne
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Department of Forensic Biology, Oslo University Hospital, Oslo, Norway
| | - Tove Irene Klokk
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.,Regional Committees for Medical and Health Research Ethics, University of Oslo, Oslo, Norway
| | | | | | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway. .,Department of Biosciences, University of Oslo, Oslo, Norway.
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21
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Mesquita FS, van der Goot FG, Sergeeva OA. Mammalian membrane trafficking as seen through the lens of bacterial toxins. Cell Microbiol 2020; 22:e13167. [PMID: 32185902 PMCID: PMC7154709 DOI: 10.1111/cmi.13167] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/15/2020] [Accepted: 01/17/2020] [Indexed: 12/12/2022]
Abstract
A fundamental question of eukaryotic cell biology is how membrane organelles are organised and interact with each other. Cell biologists address these questions by characterising the structural features of membrane compartments and the mechanisms that coordinate their exchange. To do so, they must rely on variety of cargo molecules and treatments that enable targeted perturbation, localisation, and labelling of specific compartments. In this context, bacterial toxins emerged in cell biology as paradigm shifting molecules that enabled scientists to not only study them from the side of bacterial infection but also from the side of the mammalian host. Their selectivity, potency, and versatility made them exquisite tools for uncovering much of our current understanding of membrane trafficking mechanisms. Here, we will follow the steps that lead toxins until their intracellular targets, highlighting how specific events helped us comprehend membrane trafficking and establish the fundamentals of various cellular organelles and processes. Bacterial toxins will continue to guide us in answering crucial questions in cellular biology while also acting as probes for new technologies and applications.
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Affiliation(s)
| | | | - Oksana A Sergeeva
- Global Health Institute, School of Life Sciences, EPFL, Lausanne, Switzerland
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22
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Functional dissection of the retrograde Shiga toxin trafficking inhibitor Retro-2. Nat Chem Biol 2020; 16:327-336. [PMID: 32080624 PMCID: PMC7039708 DOI: 10.1038/s41589-020-0474-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/10/2020] [Indexed: 11/29/2022]
Abstract
The retrograde transport inhibitor Retro-2 has a protective effect on cells and in mice against Shiga-like toxins and ricin. Retro-2 causes toxin accumulation in early endosomes, and relocalization of the Golgi SNARE protein syntaxin-5 to the endoplasmic reticulum. The molecular mechanisms by which this is achieved remain unknown. Here, we show that Retro-2 targets the endoplasmic reticulum exit site component Sec16A, affecting anterograde transport of syntaxin-5 from the endoplasmic reticulum to the Golgi. The formation of canonical SNARE complexes involving syntaxin-5 is not affected in Retro-2-treated cells. In contrast, the interaction of syntaxin-5 with a newly discovered binding partner, the retrograde trafficking chaperone GPP130, is abolished, and we show that GPP130 must indeed bind to syntaxin-5 to drive Shiga toxin transport from endosomes to the Golgi. We thereby identify Sec16A as a druggable target, and provide evidence for a non-SNARE function for syntaxin-5 in interaction with the GPP130.
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23
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Saraste J, Prydz K. A New Look at the Functional Organization of the Golgi Ribbon. Front Cell Dev Biol 2019; 7:171. [PMID: 31497600 PMCID: PMC6713163 DOI: 10.3389/fcell.2019.00171] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/07/2019] [Indexed: 12/14/2022] Open
Abstract
A characteristic feature of vertebrate cells is a Golgi ribbon consisting of multiple cisternal stacks connected into a single-copy organelle next to the centrosome. Despite numerous studies, the mechanisms that link the stacks together and the functional significance of ribbon formation remain poorly understood. Nevertheless, these questions are of considerable interest, since there is increasing evidence that Golgi fragmentation – the unlinking of the stacks in the ribbon – is intimately connected not only to normal physiological processes, such as cell division and migration, but also to pathological states, including neurodegeneration and cancer. Challenging a commonly held view that ribbon architecture involves the formation of homotypic tubular bridges between the Golgi stacks, we present an alternative model, based on direct interaction between the biosynthetic (pre-Golgi) and endocytic (post-Golgi) membrane networks and their connection with the centrosome. We propose that the central domains of these permanent pre- and post-Golgi networks function together in the biogenesis and maintenance of the more transient Golgi stacks, and thereby establish “linker compartments” that dynamically join the stacks together. This model provides insight into the reversible fragmentation of the Golgi ribbon that takes place in dividing and migrating cells and its regulation along a cell surface – Golgi – centrosome axis. Moreover, it helps to understand transport pathways that either traverse or bypass the Golgi stacks and the positioning of the Golgi apparatus in differentiated neuronal, epithelial, and muscle cells.
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Affiliation(s)
- Jaakko Saraste
- Department of Biomedicine and Molecular Imaging Center, University of Bergen, Bergen, Norway
| | - Kristian Prydz
- Department of Biosciences, University of Oslo, Oslo, Norway
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24
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Franke H, Scholl R, Aigner A. Ricin and Ricinus communis in pharmacology and toxicology-from ancient use and "Papyrus Ebers" to modern perspectives and "poisonous plant of the year 2018". Naunyn Schmiedebergs Arch Pharmacol 2019; 392:1181-1208. [PMID: 31359089 DOI: 10.1007/s00210-019-01691-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/04/2019] [Indexed: 12/19/2022]
Abstract
While probably originating from Africa, the plant Ricinus communis is found nowadays around the world, grown for industrial use as a source of castor oil production, wildly sprouting in many regions, or used as ornamental plant. As regards its pharmacological utility, a variety of medical purposes of selected parts of the plant, e.g., as a laxative, an anti-infective, or an anti-inflammatory drug, have been described already in the sixteenth century BC in the famous Papyrus Ebers (treasured in the Library of the University of Leipzig). Quite in contrast, on the toxicological side, the native plant has become the "poisonous plant 2018" in Germany. As of today, a number of isolated components of the plant/seeds have been characterized, including, e.g., castor oil, ricin, Ricinus communis agglutinin, ricinin, nudiflorin, and several allergenic compounds. This review mainly focuses on the most toxic protein, ricin D, classified as a type 2 ribosome-inactivating protein (RIP2). Ricin is one of the most potent and lethal substances known. It has been considered as an important bioweapon (categorized as a Category B agent (second-highest priority)) and an attractive agent for bioterroristic activities. On the other hand, ricin presents great potential, e.g., as an anti-cancer agent or in cell-based research, and is even explored in the context of nanoparticle formulations in tumor therapy. This review provides a comprehensive overview of the pharmacology and toxicology-related body of knowledge on ricin. Toxicokinetic/toxicodynamic aspects of ricin poisoning and possibilities for analytical detection and therapeutic use are summarized as well.
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Affiliation(s)
- Heike Franke
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Medical Faculty, University of Leipzig, Haertelstrasse 16-18, 04107, Leipzig, Germany.
| | - Reinhold Scholl
- Department of History, University of Leipzig, Leipzig, Germany
| | - Achim Aigner
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Clinical Pharmacology, Medical Faculty, University of Leipzig, Leipzig, Germany
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25
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Dejgaard SY, Presley JF. Rab18: new insights into the function of an essential protein. Cell Mol Life Sci 2019; 76:1935-1945. [PMID: 30830238 PMCID: PMC11105521 DOI: 10.1007/s00018-019-03050-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 02/14/2019] [Accepted: 02/19/2019] [Indexed: 12/14/2022]
Abstract
Rab18 is one of the small number of conserved Rab proteins which have been traced to the last eukaryotic common ancestor. It is found in organisms ranging from humans to trypanosomes, and localizes to multiple organelles, including most notably endoplasmic reticulum and lipid droplets. In humans, absence of Rab18 leads to a severe illness known as Warburg-Micro syndrome. Despite this evidence that Rab18 is essential, its role in cells remains mysterious. However, recent studies identifying effectors and interactors of Rab18, are now shedding light on its mechanism of action, suggesting functions related to organelle tethering and to autophagy. In this review, we examine the variety of roles proposed for Rab18 with a focus on new evidence giving insights into the molecular mechanisms it utilizes. Based on this summary of our current understanding, we identify priority areas for further research.
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Affiliation(s)
- Selma Yilmaz Dejgaard
- Department of Medical Biology, Near East University, Nicosia, Cyprus
- Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, QC, H3A 0C7, Canada
| | - John F Presley
- Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, QC, H3A 0C7, Canada.
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26
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Chang SJ, Jin SC, Jiao X, Galán JE. Unique features in the intracellular transport of typhoid toxin revealed by a genome-wide screen. PLoS Pathog 2019; 15:e1007704. [PMID: 30951565 PMCID: PMC6469816 DOI: 10.1371/journal.ppat.1007704] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/17/2019] [Accepted: 03/13/2019] [Indexed: 12/29/2022] Open
Abstract
Typhoid toxin is a virulence factor for Salmonella Typhi and Paratyphi, the cause of typhoid fever in humans. This toxin has a unique architecture in that its pentameric B subunit, made of PltB, is linked to two enzymatic A subunits, the ADP ribosyl transferase PltA and the deoxyribonuclease CdtB. Typhoid toxin is uniquely adapted to humans, recognizing surface glycoprotein sialoglycans terminated in acetyl neuraminic acid, which are preferentially expressed by human cells. The transport pathway to its cellular targets followed by typhoid toxin after receptor binding is currently unknown. Through a genome-wide CRISPR/Cas9-mediated screen we have characterized the mechanisms by which typhoid toxin is transported within human cells. We found that typhoid toxin hijacks specific elements of the retrograde transport and endoplasmic reticulum-associated degradation machineries to reach its subcellular destination within target cells. Our study reveals unique and common features in the transport mechanisms of bacterial toxins that could serve as the bases for the development of novel anti-toxin therapeutic strategies.
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Affiliation(s)
- Shu-Jung Chang
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sheng Chih Jin
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Xuyao Jiao
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Jorge E Galán
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
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27
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Abstract
The Golgi apparatus is a central sorting station in the cell. It receives newly synthesized molecules from the endoplasmic reticulum and directs them to different subcellular destinations, such as the plasma membrane or the endocytic pathway. Importantly, in the last few years, it has emerged that the maintenance of Golgi structure is connected to the proper regulation of membrane trafficking. Rab proteins are small GTPases that are considered to be the master regulators of the intracellular membrane trafficking. Several of the over 60 human Rabs are involved in the regulation of transport pathways at the Golgi as well as in the maintenance of its architecture. This chapter will summarize the different roles of Rab GTPases at the Golgi, both as regulators of membrane transport, scaffold, and tethering proteins and in preserving the structure and function of this organelle.
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28
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Tian S, Muneeruddin K, Choi MY, Tao L, Bhuiyan RH, Ohmi Y, Furukawa K, Furukawa K, Boland S, Shaffer SA, Adam RM, Dong M. Genome-wide CRISPR screens for Shiga toxins and ricin reveal Golgi proteins critical for glycosylation. PLoS Biol 2018; 16:e2006951. [PMID: 30481169 PMCID: PMC6258472 DOI: 10.1371/journal.pbio.2006951] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/02/2018] [Indexed: 12/15/2022] Open
Abstract
Glycosylation is a fundamental modification of proteins and membrane lipids. Toxins that utilize glycans as their receptors have served as powerful tools to identify key players in glycosylation processes. Here, we carried out Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9-mediated genome-wide loss-of-function screens using two related bacterial toxins, Shiga-like toxins (Stxs) 1 and 2, which use a specific glycolipid, globotriaosylceramide (Gb3), as receptors, and the plant toxin ricin, which recognizes a broad range of glycans. The Stxs screens identified major glycosyltransferases (GTs) and transporters involved in Gb3 biosynthesis, while the ricin screen identified GTs and transporters involved in N-linked protein glycosylation and fucosylation. The screens also identified lysosomal-associated protein transmembrane 4 alpha (LAPTM4A), a poorly characterized four-pass membrane protein, as a factor specifically required for Stxs. Mass spectrometry analysis of glycolipids and their precursors demonstrates that LAPTM4A knockout (KO) cells lack Gb3 biosynthesis. This requirement of LAPTM4A for Gb3 synthesis is not shared by its homolog lysosomal-associated protein transmembrane 4 beta (LAPTM4B), and switching the domains between them determined that the second luminal domain of LAPTM4A is required, potentially acting as a specific "activator" for the GT that synthesizes Gb3. These screens also revealed two Golgi proteins, Transmembrane protein 165 (TMEM165) and Transmembrane 9 superfamily member 2 (TM9SF2), as shared factors required for both Stxs and ricin. TMEM165 KO and TM9SF2 KO cells both showed a reduction in not only Gb3 but also other glycosphingolipids, suggesting that they are required for maintaining proper levels of glycosylation in general in the Golgi. In addition, TM9SF2 KO cells also showed defective endosomal trafficking. These studies reveal key Golgi proteins critical for regulating glycosylation and glycolipid synthesis and provide novel therapeutic targets for blocking Stxs and ricin toxicity.
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Affiliation(s)
- Songhai Tian
- Department of Urology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Khaja Muneeruddin
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, Massachusetts, United States of America
| | - Mei Yuk Choi
- Division of Genetics, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Liang Tao
- Department of Urology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Robiul H. Bhuiyan
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Matsumoto, Kasugai, Aichi, Japan
| | - Yuhsuke Ohmi
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Matsumoto, Kasugai, Aichi, Japan
| | - Keiko Furukawa
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Matsumoto, Kasugai, Aichi, Japan
| | - Koichi Furukawa
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Matsumoto, Kasugai, Aichi, Japan
| | - Sebastian Boland
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Scott A. Shaffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, Massachusetts, United States of America
| | - Rosalyn M. Adam
- Department of Urology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Min Dong
- Department of Urology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
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29
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Watanabe-Takahashi M, Yamasaki S, Murata M, Kano F, Motoyama J, Yamate J, Omi J, Sato W, Ukai H, Shimasaki K, Ikegawa M, Tamura-Nakano M, Yanoshita R, Nishino Y, Miyazawa A, Natori Y, Toyama-Sorimachi N, Nishikawa K. Exosome-associated Shiga toxin 2 is released from cells and causes severe toxicity in mice. Sci Rep 2018; 8:10776. [PMID: 30018364 PMCID: PMC6050230 DOI: 10.1038/s41598-018-29128-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 06/27/2018] [Indexed: 12/20/2022] Open
Abstract
Shiga toxin (Stx), a major virulence factor of enterohemorrhagic Escherichia coli (EHEC), is classified into two subgroups, Stx1 and Stx2. Clinical data clearly indicate that Stx2 is associated with more severe toxicity than Stx1, but the molecular mechanism underlying this difference is not fully understood. Here, we found that after being incorporated into target cells, Stx2, can be transported by recycling endosomes, as well as via the regular retrograde transport pathway. However, transport via recycling endosome did not occur with Stx1. We also found that Stx2 is actively released from cells in a receptor-recognizing B-subunit dependent manner. Part of the released Stx2 is associated with microvesicles, including exosome markers (referred to as exo-Stx2), whose origin is in the multivesicular bodies that formed from late/recycling endosomes. Finally, intravenous administration of exo-Stx2 to mice causes more lethality and tissue damage, especially severe renal dysfunction and tubular epithelial cell damage, compared to a free form of Stx2. Thus, the formation of exo-Stx2 might contribute to the severity of Stx2 in vivo, suggesting new therapeutic strategies against EHEC infections.
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Affiliation(s)
- Miho Watanabe-Takahashi
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Shinji Yamasaki
- International Prevention of Epidemics, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Fumi Kano
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, Japan
| | - Jun Motoyama
- Laboratory of Developmental Neurobiology, Graduate School of Brain Sciences, Doshisha University, Kyoto, Japan
| | - Jyoji Yamate
- Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan
| | - Jumpei Omi
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Waka Sato
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Hirofumi Ukai
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Kentaro Shimasaki
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Masaya Ikegawa
- Genomics, Proteomics and Biomedical Functions, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan
| | - Miwa Tamura-Nakano
- Communal Laboratory, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Ryohei Yanoshita
- Department of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, Teikyo Heisei University, Tokyo, Japan
| | - Yuri Nishino
- Graduate School of Life Science, University of Hyogo, Hyogo, Japan
| | - Atsuo Miyazawa
- Graduate School of Life Science, University of Hyogo, Hyogo, Japan
| | - Yasuhiro Natori
- Department of Health Chemistry, School of Pharmacy, Iwate Medical University, Iwate, Japan
| | - Noriko Toyama-Sorimachi
- Department of Molecular Immunology and Inflammation, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Kiyotaka Nishikawa
- Department of Molecular Life Sciences, Graduate School of Life and Medical Sciences, Doshisha University, Kyoto, Japan.
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30
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A versatile nanobody-based toolkit to analyze retrograde transport from the cell surface. Proc Natl Acad Sci U S A 2018; 115:E6227-E6236. [PMID: 29915061 DOI: 10.1073/pnas.1801865115] [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] [Indexed: 02/06/2023] Open
Abstract
Retrograde transport of membranes and proteins from the cell surface to the Golgi and beyond is essential to maintain homeostasis, compartment identity, and physiological functions. To study retrograde traffic biochemically, by live-cell imaging or by electron microscopy, we engineered functionalized anti-GFP nanobodies (camelid VHH antibody domains) to be bacterially expressed and purified. Tyrosine sulfation consensus sequences were fused to the nanobody for biochemical detection of trans-Golgi arrival, fluorophores for fluorescence microscopy and live imaging, and APEX2 (ascorbate peroxidase 2) for electron microscopy and compartment ablation. These functionalized nanobodies are specifically captured by GFP-modified reporter proteins at the cell surface and transported piggyback to the reporters' homing compartments. As an application of this tool, we have used it to determine the contribution of adaptor protein-1/clathrin in retrograde transport kinetics of the mannose-6-phosphate receptors from endosomes back to the trans-Golgi network. Our experiments establish functionalized nanobodies as a powerful tool to demonstrate and quantify retrograde transport pathways.
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31
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Kavaliauskiene S, Torgersen ML, Lingelem ABD, Klokk TI, Lintonen T, Simolin H, Ekroos K, Skotland T, Sandvig K. Cellular effects of fluorodeoxyglucose: Global changes in the lipidome and alteration in intracellular transport. Oncotarget 2018; 7:79885-79900. [PMID: 27829218 PMCID: PMC5346758 DOI: 10.18632/oncotarget.13089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 10/21/2016] [Indexed: 11/29/2022] Open
Abstract
2-fluoro-2-deoxy-D-glucose (FDG), labeled with 18F radioisotope, is the most common imaging agent used for positron emission tomography (PET) in oncology. However, little is known about the cellular effects of FDG. Another glucose analogue, 2-deoxy-D-glucose (2DG), has been shown to affect many cellular functions, including intracellular transport and lipid metabolism, and has been found to improve the efficacy of cancer chemotherapeutic agents in vivo. Thus, in the present study, we have investigated cellular effects of FDG with the focus on changes in cellular lipids and intracellular transport. By quantifying more than 200 lipids from 17 different lipid classes in HEp-2 cells and by analyzing glycosphingolipids from MCF-7, HT-29 and HBMEC cells, we have discovered that FDG treatment inhibits glucosylceramide synthesis and thus reduces cellular levels of glycosphingolipids. In addition, in HEp-2 cells the levels and/or species composition of other lipid classes, namely diacylglycerols, phosphatidic acids and phosphatidylinositols, were found to change upon treatment with FDG. Furthermore, we show here that FDG inhibits retrograde Shiga toxin transport and is much more efficient in protecting cells against the toxin than 2DG. In summary, our data reveal novel effects of FDG on cellular transport and glycosphingolipid metabolism, which suggest a potential clinical application of FDG as an adjuvant for cancer chemotherapy.
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Affiliation(s)
- Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Maria Lyngaas Torgersen
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Anne Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Tove Irene Klokk
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
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32
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Luginbuehl V, Meier N, Kovar K, Rohrer J. Intracellular drug delivery: Potential usefulness of engineered Shiga toxin subunit B for targeted cancer therapy. Biotechnol Adv 2018; 36:613-623. [PMID: 29432805 DOI: 10.1016/j.biotechadv.2018.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 01/30/2018] [Accepted: 02/05/2018] [Indexed: 12/15/2022]
Abstract
A treasure trove of intracellular cancer drug targets remains hidden behind cell membranes. However, engineered pathogen-derived toxins such as Shiga toxins can deliver small or macromolecular drugs to specific intracellular organelles. After binding to ganglioglobotriaosylceramide (Gb3, CD77), the non-toxic subunit B (StxB) of the Shiga-holotoxin is endocytosed and delivers its payload by a unique retrograde trafficking pathway via the endoplasmic reticulum to the cytosol. This review provides an overview of biomedical applications of StxB-based drug delivery systems in targeted cancer diagnosis and therapy. Biotechnological production of the Stx-material is discussed from the perspective of developing efficacious and safe therapeutics.
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Affiliation(s)
- Vera Luginbuehl
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Nicolas Meier
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Karin Kovar
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland
| | - Jack Rohrer
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, Grueental, P.O.X. 335, CH-8820 Waedenswil, Switzerland.
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Makaraci P, Kim K. trans-Golgi network-bound cargo traffic. Eur J Cell Biol 2018; 97:137-149. [PMID: 29398202 DOI: 10.1016/j.ejcb.2018.01.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/15/2017] [Accepted: 01/16/2018] [Indexed: 12/19/2022] Open
Abstract
Cargo following the retrograde trafficking are sorted at endosomes to be targeted the trans-Golgi network (TGN), a central receiving organelle. Though molecular requirements and their interaction networks have been somewhat established, the complete understanding of the intricate nature of their action mechanisms in every step of the retrograde traffic pathway remains unachieved. This review focuses on elucidating known functions of key regulators, including scission factors at the endosome and tethering/fusion mediators at the receiving dock, TGN, as well as a diverse range of cargo.
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Affiliation(s)
- Pelin Makaraci
- Department of Biology, Missouri State University, 901 S National Ave., Springfield, MO 65807, USA
| | - Kyoungtae Kim
- Department of Biology, Missouri State University, 901 S National Ave., Springfield, MO 65807, USA.
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Vance DJ, Tremblay JM, Rong Y, Angalakurthi SK, Volkin DB, Middaugh CR, Weis DD, Shoemaker CB, Mantis NJ. High-Resolution Epitope Positioning of a Large Collection of Neutralizing and Nonneutralizing Single-Domain Antibodies on the Enzymatic and Binding Subunits of Ricin Toxin. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:e00236-17. [PMID: 29021300 PMCID: PMC5717184 DOI: 10.1128/cvi.00236-17] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 10/02/2017] [Indexed: 01/05/2023]
Abstract
We previously produced a heavy-chain-only antibody (Ab) VH domain (VHH)-displayed phage library from two alpacas that had been immunized with ricin toxoid and nontoxic mixtures of the enzymatic ricin toxin A subunit (RTA) and binding ricin toxin B subunit (RTB) (D. J. Vance, J. M. Tremblay, N. J. Mantis, and C. B. Shoemaker, J Biol Chem 288:36538-36547, 2013, https://doi.org/10.1074/jbc.M113.519207). Initial and subsequent screens of that library by direct enzyme-linked immunosorbent assay (ELISA) yielded more than two dozen unique RTA- and RTB-specific VHHs, including 10 whose structures were subsequently solved in complex with RTA. To generate a more complete antigenic map of ricin toxin and to define the epitopes associated with toxin-neutralizing activity, we subjected the VHH-displayed phage library to additional "pannings" on both receptor-bound ricin and antibody-captured ricin. We now report the full-length DNA sequences, binding affinities, and neutralizing activities of 68 unique VHHs: 31 against RTA, 33 against RTB, and 4 against ricin holotoxin. Epitope positioning was achieved through cross-competition ELISAs performed with a panel of monoclonal antibodies (MAbs) and verified, in some instances, with hydrogen-deuterium exchange mass spectrometry. The 68 VHHs grouped into more than 20 different competition bins. The RTA-specific VHHs with strong toxin-neutralizing activities were confined to bins that overlapped two previously identified neutralizing hot spots, termed clusters I and II. The four RTB-specific VHHs with potent toxin-neutralizing activity grouped within three adjacent bins situated at the RTA-RTB interface near cluster II. These results provide important insights into epitope interrelationships on the surface of ricin and delineate regions of vulnerability that can be exploited for the purpose of vaccine and therapeutic development.
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Affiliation(s)
- David J Vance
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Jacqueline M Tremblay
- Department of Infectious Disease and Global Health, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachusetts, USA
| | - Yinghui Rong
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Siva Krishna Angalakurthi
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, USA
| | - David B Volkin
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, USA
| | - C Russell Middaugh
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, USA
| | - David D Weis
- Department of Chemistry, University of Kansas, Lawrence, Kansas, USA
| | - Charles B Shoemaker
- Department of Infectious Disease and Global Health, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachusetts, USA
| | - Nicholas J Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, New York, USA
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Microvesicle Involvement in Shiga Toxin-Associated Infection. Toxins (Basel) 2017; 9:toxins9110376. [PMID: 29156596 PMCID: PMC5705991 DOI: 10.3390/toxins9110376] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/15/2017] [Accepted: 11/16/2017] [Indexed: 12/16/2022] Open
Abstract
Shiga toxin is the main virulence factor of enterohemorrhagic Escherichia coli, a non-invasive pathogen that releases virulence factors in the intestine, causing hemorrhagic colitis and, in severe cases, hemolytic uremic syndrome (HUS). HUS manifests with acute renal failure, hemolytic anemia and thrombocytopenia. Shiga toxin induces endothelial cell damage leading to platelet deposition in thrombi within the microvasculature and the development of thrombotic microangiopathy, mostly affecting the kidney. Red blood cells are destroyed in the occlusive capillary lesions. This review focuses on the importance of microvesicles shed from blood cells and their participation in the prothrombotic lesion, in hemolysis and in the transfer of toxin from the circulation into the kidney. Shiga toxin binds to blood cells and may undergo endocytosis and be released within microvesicles. Microvesicles normally contribute to intracellular communication and remove unwanted components from cells. Many microvesicles are prothrombotic as they are tissue factor- and phosphatidylserine-positive. Shiga toxin induces complement-mediated hemolysis and the release of complement-coated red blood cell-derived microvesicles. Toxin was demonstrated within blood cell-derived microvesicles that transported it to renal cells, where microvesicles were taken up and released their contents. Microvesicles are thereby involved in all cardinal aspects of Shiga toxin-associated HUS, thrombosis, hemolysis and renal failure.
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A vital sugar code for ricin toxicity. Cell Res 2017; 27:1351-1364. [PMID: 28925387 PMCID: PMC5674155 DOI: 10.1038/cr.2017.116] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 07/24/2017] [Accepted: 07/26/2017] [Indexed: 12/12/2022] Open
Abstract
Ricin is one of the most feared bioweapons in the world due to its extreme toxicity and easy access. Since no antidote exists, it is of paramount importance to identify the pathways underlying ricin toxicity. Here, we demonstrate that the Golgi GDP-fucose transporter Slc35c1 and fucosyltransferase Fut9 are key regulators of ricin toxicity. Genetic and pharmacological inhibition of fucosylation renders diverse cell types resistant to ricin via deregulated intracellular trafficking. Importantly, cells from a patient with SLC35C1 deficiency are also resistant to ricin. Mechanistically, we confirm that reduced fucosylation leads to increased sialylation of Lewis X structures and thus masking of ricin-binding sites. Inactivation of the sialyltransferase responsible for modifications of Lewis X (St3Gal4) increases the sensitivity of cells to ricin, whereas its overexpression renders cells more resistant to the toxin. Thus, we have provided unprecedented insights into an evolutionary conserved modular sugar code that can be manipulated to control ricin toxicity.
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Bazzoli A, Vance DJ, Rudolph MJ, Rong Y, Angalakurthi SK, Toth RT, Middaugh CR, Volkin DB, Weis DD, Karanicolas J, Mantis NJ. Using homology modeling to interrogate binding affinity in neutralization of ricin toxin by a family of single domain antibodies. Proteins 2017; 85:1994-2008. [PMID: 28718923 DOI: 10.1002/prot.25353] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 12/12/2022]
Abstract
In this report we investigated, within a group of closely related single domain camelid antibodies (VH Hs), the relationship between binding affinity and neutralizing activity as it pertains to ricin, a fast-acting toxin and biothreat agent. The V1C7-like VH Hs (V1C7, V2B9, V2E8, and V5C1) are similar in amino acid sequence, but differ in their binding affinities and toxin-neutralizing activities. Using the X-ray crystal structure of V1C7 in complex with ricin's enzymatic subunit (RTA) as a template, Rosetta-based homology modeling coupled with energetic decomposition led us to predict that a single pairwise interaction between Arg29 on V5C1 and Glu67 on RTA was responsible for the difference in ricin toxin binding affinity between V1C7, a weak neutralizer, and V5C1, a moderate neutralizer. This prediction was borne out experimentally: substitution of Arg for Gly at position 29 enhanced V1C7's binding affinity for ricin, whereas the reverse (ie, Gly for Arg at position 29) diminished V5C1's binding affinity by >10 fold. As expected, the V5C1R29G mutant was largely devoid of toxin-neutralizing activity (TNA). However, the TNA of the V1C7G29R mutant was not correspondingly improved, indicating that in the V1C7 family binding affinity alone does not account for differences in antibody function. V1C7 and V5C1, as well as their respective point mutants, recognized indistinguishable epitopes on RTA, at least at the level of sensitivity afforded by hydrogen-deuterium mass spectrometry. The results of this study have implications for engineering therapeutic antibodies because they demonstrate that even subtle differences in epitope specificity can account for important differences in antibody function.
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Affiliation(s)
- Andrea Bazzoli
- Center for Computational Biology, University of Kansas, Lawrence, Kansas, 66045.,Computational Chemical Biology Core, University of Kansas, Lawrence, Kansas, 66047
| | - David J Vance
- New York State Department of Health, Division of Infectious Diseases, Wadsworth Center, Albany, New York, 12208
| | | | - Yinghui Rong
- New York State Department of Health, Division of Infectious Diseases, Wadsworth Center, Albany, New York, 12208
| | - Siva Krishna Angalakurthi
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66045
| | - Ronald T Toth
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66045
| | - C Russell Middaugh
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66045
| | - David B Volkin
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66045
| | - David D Weis
- Department of Chemistry, University of Kansas, Lawrence, Kansas, 66045
| | - John Karanicolas
- Center for Computational Biology, University of Kansas, Lawrence, Kansas, 66045.,Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, 66045.,Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania, 19111
| | - Nicholas J Mantis
- New York State Department of Health, Division of Infectious Diseases, Wadsworth Center, Albany, New York, 12208
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Abstract
Clostridium difficile is the cause of antibiotics-associated diarrhea and pseudomembranous colitis. The pathogen produces three protein toxins: C. difficile toxins A (TcdA) and B (TcdB), and C. difficile transferase toxin (CDT). The single-chain toxins TcdA and TcdB are the main virulence factors. They bind to cell membrane receptors and are internalized. The N-terminal glucosyltransferase and autoprotease domains of the toxins translocate from low-pH endosomes into the cytosol. After activation by inositol hexakisphosphate (InsP6), the autoprotease cleaves and releases the glucosyltransferase domain into the cytosol, where GTP-binding proteins of the Rho/Ras family are mono-O-glucosylated and, thereby, inactivated. Inactivation of Rho proteins disturbs the organization of the cytoskeleton and affects multiple Rho-dependent cellular processes, including loss of epithelial barrier functions, induction of apoptosis, and inflammation. CDT, the third C. difficile toxin, is a binary actin-ADP-ribosylating toxin that causes depolymerization of actin, thereby inducing formation of the microtubule-based protrusions. Recent progress in understanding of the toxins' actions include insights into the toxin structures, their interaction with host cells, and functional consequences of their actions.
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Affiliation(s)
- Klaus Aktories
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
| | - Carsten Schwan
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
| | - Thomas Jank
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
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Bielaszewska M, Rüter C, Bauwens A, Greune L, Jarosch KA, Steil D, Zhang W, He X, Lloubes R, Fruth A, Kim KS, Schmidt MA, Dobrindt U, Mellmann A, Karch H. Host cell interactions of outer membrane vesicle-associated virulence factors of enterohemorrhagic Escherichia coli O157: Intracellular delivery, trafficking and mechanisms of cell injury. PLoS Pathog 2017; 13:e1006159. [PMID: 28158302 PMCID: PMC5310930 DOI: 10.1371/journal.ppat.1006159] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 02/15/2017] [Accepted: 12/30/2016] [Indexed: 01/15/2023] Open
Abstract
Outer membrane vesicles (OMVs) are important tools in bacterial virulence but their role in the pathogenesis of infections caused by enterohemorrhagic Escherichia coli (EHEC) O157, the leading cause of life-threatening hemolytic uremic syndrome, is poorly understood. Using proteomics, electron and confocal laser scanning microscopy, immunoblotting, and bioassays, we investigated OMVs secreted by EHEC O157 clinical isolates for virulence factors cargoes, interactions with pathogenetically relevant human cells, and mechanisms of cell injury. We demonstrate that O157 OMVs carry a cocktail of key virulence factors of EHEC O157 including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, and flagellin. The toxins are internalized by cells via dynamin-dependent endocytosis of OMVs and differentially separate from vesicles during intracellular trafficking. Stx2a and CdtV-B, the DNase-like CdtV subunit, separate from OMVs in early endosomes. Stx2a is trafficked, in association with its receptor globotriaosylceramide within detergent-resistant membranes, to the Golgi complex and the endoplasmic reticulum from where the catalytic Stx2a A1 fragment is translocated to the cytosol. CdtV-B is, after its retrograde transport to the endoplasmic reticulum, translocated to the nucleus to reach DNA. CdtV-A and CdtV-C subunits remain OMV-associated and are sorted with OMVs to lysosomes. EHEC hemolysin separates from OMVs in lysosomes and targets mitochondria. The OMV-delivered CdtV-B causes cellular DNA damage, which activates DNA damage responses leading to G2 cell cycle arrest. The arrested cells ultimately die of apoptosis induced by Stx2a and CdtV via caspase-9 activation. By demonstrating that naturally secreted EHEC O157 OMVs carry and deliver into cells a cocktail of biologically active virulence factors, thereby causing cell death, and by performing first comprehensive analysis of intracellular trafficking of OMVs and OMV-delivered virulence factors, we provide new insights into the pathogenesis of EHEC O157 infections. Our data have implications for considering O157 OMVs as vaccine candidates. Enterohemorrhagic Escherichia coli (EHEC) O157, the leading EHEC group causing diarrhea and the life-threatening hemolytic uremic syndrome in humans, produce several virulence factors which play distinct roles in the pathogenesis of these diseases. However, the mechanisms of their secretion and host cell injury are poorly understood. We show here that EHEC O157 strains isolated from patients shed nanostructures termed outer membrane vesicles (OMVs) which contain major EHEC O157 virulence factors including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, and flagellin. The OMVs are taken up by human intestinal epithelial and renal and brain microvascular endothelial cells, which are the major targets during EHEC O157 infections, and deliver the virulence factors intracellularly. Inside cells the virulence factors separate from OMVs and are transported via different pathways to their target compartments including the cytosol (Stx2a), nucleus (CdtV-B subunit), and mitochondria (EHEC hemolysin). Cells exposed to EHEC O157 OMVs develop G2 cell cycle arrest induced by CdtV-B-mediated DNA damage. This is followed by apoptotic cell death triggered by Stx2a and CdtV via caspase-9 activation. OMVs thus serve as novel tools of EHEC O157-mediated host injury and are quite likely involved in the pathogenesis of human diseases.
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Affiliation(s)
| | - Christian Rüter
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany
| | - Andreas Bauwens
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Lilo Greune
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany
| | | | - Daniel Steil
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Wenlan Zhang
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Xiaohua He
- Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture (USDA), Albany, California, United States of America
| | - Roland Lloubes
- Laboratoire d'Ingenierie des Systemes Macromoleculaires UMR7255, CNRS-Aix-Marseille Université, Marseille, France
| | - Angelika Fruth
- National Reference Center for Salmonella and Other Enteric Pathogens, Robert Koch Institute, Branch Wernigerode, Wernigerode, Germany
| | - Kwang Sik Kim
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - M. Alexander Schmidt
- Institute of Infectiology, Center for Molecular Biology of Inflammation (ZMBE), University of Münster, Münster, Germany
| | - Ulrich Dobrindt
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Alexander Mellmann
- Institute of Hygiene, University of Münster, Münster, Germany
- Interdisciplinary Center for Clinical Research (IZKF), University of Münster, Münster, Germany
| | - Helge Karch
- Institute of Hygiene, University of Münster, Münster, Germany
- Interdisciplinary Center for Clinical Research (IZKF), University of Münster, Münster, Germany
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Herrera C, Mantis NJ, Cole R. Applications in Stimulated Emission Depletion Microscopy: Localization of a Protein Toxin in the Endoplasmic Reticulum Following Retrograde Transport. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2016; 22:1113-1119. [PMID: 27804914 DOI: 10.1017/s1431927616011879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Retrograde transport is a process in which proteins are trafficked from the plasma membrane and endosomes to biosynthetic and secretory organelles, namely the Golgi apparatus and endoplasmic reticulum (ER). A number of plant and bacterial toxins, including cholera toxin and ricin toxin, exploit retrograde transport to gain entry into host cells, although the specifics of this process have remained difficult to probe by laser scanning confocal microscopy (LSCM). Here we demonstrate the use of super-resolution and live-cell imaging [stimulated emission depletion (STED)] to visualize exogenously applied ricin toxin within the ER. The improved resolution obtained by STED, as compared with LSCM (0.09 versus 0.19 μm), provides a more accurate determination of the amount of ricin that had trafficked to the ER.
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Affiliation(s)
- Cristina Herrera
- 1Wadsworth Center,Division of Infectious Disease,New York State Department of Health,Albany,NY 12208,USA
| | - Nicholas J Mantis
- 1Wadsworth Center,Division of Infectious Disease,New York State Department of Health,Albany,NY 12208,USA
| | - Richard Cole
- 2Department of Biomedical Sciences,University at Albany School of Public Health,Albany,NY 12201,USA
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Vance DJ, Mantis NJ. Progress and challenges associated with the development of ricin toxin subunit vaccines. Expert Rev Vaccines 2016; 15:1213-22. [PMID: 26998662 PMCID: PMC5193006 DOI: 10.1586/14760584.2016.1168701] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The past several years have seen major advances in the development of a safe and efficacious ricin toxin vaccine, including the completion of two Phase I clinical trials with two different recombinant A subunit (RTA)-based vaccines: RiVax™ and RVEc™ adsorbed to aluminum salt adjuvant, as well as a non-human primate study demonstrating that parenteral immunization with RiVax elicits a serum antibody response that was sufficient to protect against a lethal dose aerosolized ricin exposure. One of the major obstacles moving forward is assessing vaccine efficacy in humans, when neither ricin-specific serum IgG endpoint titers nor toxin-neutralizing antibody levels are accepted as definitive predictors of protective immunity. In this review we summarize ongoing efforts to leverage recent advances in our understanding of RTA-antibody interactions at the structural level to develop novel assays to predict vaccine efficacy in humans.
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Affiliation(s)
- David J. Vance
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Nicholas J. Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, University at Albany, Albany, New York, USA
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Authier F, Djavaheri-Mergny M, Lorin S, Frénoy JP, Desbuquois B. Fate and action of ricin in rat liverin vivo: translocation of endocytosed ricin into cytosol and induction of intrinsic apoptosis by ricin B-chain. Cell Microbiol 2016; 18:1800-1814. [DOI: 10.1111/cmi.12621] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 12/13/2022]
Affiliation(s)
- François Authier
- Service information scientifique et technique (IST) de l'Inserm; Paris France
| | | | - Séverine Lorin
- Inserm UMR-S-1193; Université Paris-Saclay; 92296 Châtenay-Malabry France
| | - Jean-Pierre Frénoy
- CNRS UMR 8601, Centre Universitaire des Saints-Pères; Université Paris-Descartes; Paris France
| | - Bernard Desbuquois
- Inserm U 1016 and CNRS UMR 8104; Université Paris-Descartes, Institut Cochin; Paris France
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Abstract
Post-infectious hemolytic uremic syndrome (HUS) is caused by specific pathogens in patients with no identifiable HUS-associated genetic mutation or autoantibody. The majority of episodes is due to infections by Shiga toxin (Stx) producing Escherichia coli (STEC). This chapter reviews the epidemiology and pathogenesis of STEC-HUS, including bacterial-derived factors and host responses. STEC disease is characterized by hematological (microangiopathic hemolytic anemia), renal (acute kidney injury) and extrarenal organ involvement. Clinicians should always strive for an etiological diagnosis through the microbiological or molecular identification of Stx-producing bacteria and Stx or, if negative, serological assays. Treatment of STEC-HUS is supportive; more investigations are needed to evaluate the efficacy of putative preventive and therapeutic measures, such as non-phage-inducing antibiotics, volume expansion and anti-complement agents. The outcome of STEC-HUS is generally favorable, but chronic kidney disease, permanent extrarenal, mainly cerebral complication and death (in less than 5 %) occur and long-term follow-up is recommended. The remainder of this chapter highlights rarer forms of (post-infectious) HUS due to S. dysenteriae, S. pneumoniae, influenza A and HIV and discusses potential interactions between these pathogens and the complement system.
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Affiliation(s)
- Denis F. Geary
- Division of Nephrology, The Hospital for Sick Children, Toronto, Ontario Canada
| | - Franz Schaefer
- Division of Pediatric Nephrology, University of Heidelberg, Heidelberg, Germany
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Herrera C, Klokk TI, Cole R, Sandvig K, Mantis NJ. A Bispecific Antibody Promotes Aggregation of Ricin Toxin on Cell Surfaces and Alters Dynamics of Toxin Internalization and Trafficking. PLoS One 2016; 11:e0156893. [PMID: 27300140 PMCID: PMC4907443 DOI: 10.1371/journal.pone.0156893] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/21/2016] [Indexed: 11/19/2022] Open
Abstract
JJX12 is an engineered bispecific antibody against ricin, a member of the medically important A-B family of toxins that exploits retrograde transport as means to gain entry into the cytosol of target cells. JJX12 consists of RTA-D10, a camelid single variable domain (VHH) antibody directed against an epitope on ricin's enzymatic subunit (RTA), linked via a 15-mer peptide to RTB-B7, a VHH against ricin's bivalent galactose binding subunit (RTB). We previously reported that JJX12, but not an equimolar mixture of RTA-D10 and RTB-B7 monomers, was able to passively protect mice against a lethal dose ricin challenge, demonstrating that physically linking RTB-B7 and RTA-D10 is critical for toxin-neutralizing activity in vivo. We also reported that JJX12 promotes aggregation of ricin in solution, presumably through the formation of intermolecular crosslinking. In the current study, we now present evidence that JJX12 affects the dynamics of ricin uptake and trafficking in human epithelial cells. Confocal microscopy, as well as live cell imaging coupled with endocytosis pathway-specific inhibitors, revealed that JJX12-toxin complexes are formed on the surfaces of mammalian cells and internalized via a pathway sensitive to amiloride, a known inhibitor of macropinocytosis. Moreover, in the presence of JJX12, retrograde transport of ricin to the trans-Golgi network was significantly reduced, while accumulation of the toxin in late endosomes was significantly enhanced. In summary, we propose that JJX12, by virtue of its ability to crosslink ricin toxin, alters the route of toxin uptake and trafficking within cells.
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Affiliation(s)
- Cristina Herrera
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
| | - Tove Irene Klokk
- Department of Molecular Cell Biology and Centre for Cancer Biomedicine, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Richard Cole
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Kirsten Sandvig
- Department of Molecular Cell Biology and Centre for Cancer Biomedicine, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Nicholas J. Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
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Juliano RL. The delivery of therapeutic oligonucleotides. Nucleic Acids Res 2016; 44:6518-48. [PMID: 27084936 PMCID: PMC5001581 DOI: 10.1093/nar/gkw236] [Citation(s) in RCA: 580] [Impact Index Per Article: 72.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 03/28/2016] [Indexed: 12/14/2022] Open
Abstract
The oligonucleotide therapeutics field has seen remarkable progress over the last few years with the approval of the first antisense drug and with promising developments in late stage clinical trials using siRNA or splice switching oligonucleotides. However, effective delivery of oligonucleotides to their intracellular sites of action remains a major issue. This review will describe the biological basis of oligonucleotide delivery including the nature of various tissue barriers and the mechanisms of cellular uptake and intracellular trafficking of oligonucleotides. It will then examine a variety of current approaches for enhancing the delivery of oligonucleotides. This includes molecular scale targeted ligand-oligonucleotide conjugates, lipid- and polymer-based nanoparticles, antibody conjugates and small molecules that improve oligonucleotide delivery. The merits and liabilities of these approaches will be discussed in the context of the underlying basic biology.
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Affiliation(s)
- Rudolph L Juliano
- UNC Eshelman School of Pharmacy and UNC School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
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Neutralizing Monoclonal Antibodies against Disparate Epitopes on Ricin Toxin's Enzymatic Subunit Interfere with Intracellular Toxin Transport. Sci Rep 2016; 6:22721. [PMID: 26949061 PMCID: PMC4779987 DOI: 10.1038/srep22721] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 02/18/2016] [Indexed: 12/11/2022] Open
Abstract
Ricin is a member of the A-B family of bacterial and plant toxins that exploit retrograde trafficking to the Golgi apparatus and endoplasmic reticulum (ER) as a means to deliver their cytotoxic enzymatic subunits into the cytoplasm of mammalian cells. In this study we demonstrate that R70 and SyH7, two well-characterized monoclonal antibodies (mAbs) directed against distinct epitopes on the surface of ricin’s enzymatic subunit (RTA), interfere with toxin transport from the plasma membrane to the trans Golgi network. Toxin-mAb complexes formed on the cell surface delayed ricin’s egress from EEA-1+ and Rab7+ vesicles and enhanced toxin accumulation in LAMP-1+ vesicles, suggesting the complexes were destined for degradation in lysosomes. Three other RTA-specific neutralizing mAbs against different epitopes were similar to R70 and SyH7 in terms of their effects on ricin retrograde transport. We conclude that interference with toxin retrograde transport may be a hallmark of toxin-neutralizing antibodies directed against disparate epitopes on RTA.
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Abraham O, Gotliv K, Parnis A, Boncompain G, Perez F, Cassel D. Control of protein trafficking by reversible masking of transport signals. Mol Biol Cell 2016; 27:1310-9. [PMID: 26941332 PMCID: PMC4831884 DOI: 10.1091/mbc.e15-07-0472] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 02/23/2016] [Indexed: 02/06/2023] Open
Abstract
A system for controlled trafficking of proteins is based on modifying the streptavidin-binding peptide with trafficking signals and appending it to reporter proteins. Coexpression with streptavidin results in signal masking, which is reversed upon biotin addition. Systems that allow the control of protein traffic between subcellular compartments have been valuable in elucidating trafficking mechanisms. Most current approaches rely on ligand or light-controlled dimerization, which results in either retardation or enhancement of the transport of a reporter. We developed an alternative approach for trafficking regulation that we term “controlled unmasking of targeting elements” (CUTE). Regulated trafficking is achieved by reversible masking of the signal that directs the reporter to its target organelle, relying on the streptavidin–biotin system. The targeting signal is generated within or immediately after a 38–amino acid streptavidin-binding peptide (SBP) that is appended to the reporter. The binding of coexpressed streptavidin to SBP causes signal masking, whereas addition of biotin causes complex dissociation and triggers protein transport to the target organelle. We demonstrate the application of this approach to the control of nuclear and peroxisomal protein import and the generation of biotin-dependent trafficking through the endocytic and COPI systems. By simultaneous masking of COPI and endocytic signals, we were able to generate a synthetic pathway for efficient transport of a reporter from the plasma membrane to the endoplasmic reticulum.
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Affiliation(s)
- Omer Abraham
- Department of Biology, Technion, Haifa 320003, Israel
| | - Karnit Gotliv
- Department of Biology, Technion, Haifa 320003, Israel
| | - Anna Parnis
- Department of Biology, Technion, Haifa 320003, Israel
| | - Gaelle Boncompain
- Institut Curie, Centre de Recherche, PSL Research University, and CNRS, UMR144, Paris 75248, France
| | - Franck Perez
- Institut Curie, Centre de Recherche, PSL Research University, and CNRS, UMR144, Paris 75248, France
| | - Dan Cassel
- Department of Biology, Technion, Haifa 320003, Israel
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Helms JB, Kaloyanova DV, Strating JRP, van Hellemond JJ, van der Schaar HM, Tielens AGM, van Kuppeveld FJM, Brouwers JF. Targeting of the hydrophobic metabolome by pathogens. Traffic 2016; 16:439-60. [PMID: 25754025 PMCID: PMC7169838 DOI: 10.1111/tra.12280] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/09/2015] [Accepted: 01/09/2015] [Indexed: 12/12/2022]
Abstract
The hydrophobic molecules of the metabolome – also named the lipidome – constitute a major part of the entire metabolome. Novel technologies show the existence of a staggering number of individual lipid species, the biological functions of which are, with the exception of only a few lipid species, unknown. Much can be learned from pathogens that have evolved to take advantage of the complexity of the lipidome to escape the immune system of the host organism and to allow their survival and replication. Different types of pathogens target different lipids as shown in interaction maps, allowing visualization of differences between different types of pathogens. Bacterial and viral pathogens target predominantly structural and signaling lipids to alter the cellular phenotype of the host cell. Fungal and parasitic pathogens have complex lipidomes themselves and target predominantly the release of polyunsaturated fatty acids from the host cell lipidome, resulting in the generation of eicosanoids by either the host cell or the pathogen. Thus, whereas viruses and bacteria induce predominantly alterations in lipid metabolites at the host cell level, eukaryotic pathogens focus on interference with lipid metabolites affecting systemic inflammatory reactions that are part of the immune system. A better understanding of the interplay between host–pathogen interactions will not only help elucidate the fundamental role of lipid species in cellular physiology, but will also aid in the generation of novel therapeutic drugs.
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Affiliation(s)
- J Bernd Helms
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine & Institute of Biomembranes, Utrecht University, Yalelaan 2, 3584 CM, Utrecht, The Netherlands
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Chan YS, Ng TB. Shiga toxins: from structure and mechanism to applications. Appl Microbiol Biotechnol 2015; 100:1597-1610. [PMID: 26685676 DOI: 10.1007/s00253-015-7236-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/03/2015] [Accepted: 12/06/2015] [Indexed: 01/03/2023]
Abstract
Shiga toxins are a group of type 2 ribosome-inactivating proteins (RIPs) produced in several types of bacteria. The toxins possess an AB5 structure, which comprises a catalytic A chain with N-glycosidase activity, and five identical B chains and recognize and bind to the target cells with specific carbohydrate moieties. In humans, the major molecular target which recognizes the Shiga toxins is the Gb3 receptor, which is mainly expressed on the cell surface of endothelial cells of the intestine, kidney, and the brain. This causes these organs to be susceptible to the toxicity of Shiga toxins. When a person is infected by Shiga toxin-producing bacteria, the toxin is produced in the gut, translocated to the circulatory system, and carried to the target cells. Toxicity of the toxin causes inflammatory responses and severe cell damages in the intestine, kidneys, and brain, bringing about the hemolytic uremic syndrome (HUS), which can be fatal. The Shiga toxin requires a couple of steps to exert its toxicity to the target cells. After binding with the target cell surface receptor, the toxin requires a complicated process to be transported into the cytosol of the cell before it can approach the ribosomes. The mechanisms for the interactions of the toxin with the cells are described in this review. The consequences of the toxin on the cells are also discussed. It gives an overview of the steps for the toxin to be produced and transported, expression of catalytic activity, and the effects of the toxin on the target cells, as well as effects on the human body.
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Affiliation(s)
- Yau Sang Chan
- School of Biomedical Sciences, Lo Kwee Seong Integrated Biomedical Sciences Building, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
| | - Tzi Bun Ng
- School of Biomedical Sciences, Lo Kwee Seong Integrated Biomedical Sciences Building, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
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Herrera C, Tremblay JM, Shoemaker CB, Mantis NJ. Mechanisms of Ricin Toxin Neutralization Revealed through Engineered Homodimeric and Heterodimeric Camelid Antibodies. J Biol Chem 2015; 290:27880-9. [PMID: 26396190 DOI: 10.1074/jbc.m115.658070] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Indexed: 11/06/2022] Open
Abstract
Novel antibody constructs consisting of two or more different camelid heavy-chain only antibodies (VHHs) joined via peptide linkers have proven to have potent toxin-neutralizing activity in vivo against Shiga, botulinum, Clostridium difficile, anthrax, and ricin toxins. However, the mechanisms by which these so-called bispecific VHH heterodimers promote toxin neutralization remain poorly understood. In the current study we produced a new collection of ricin-specific VHH heterodimers, as well as VHH homodimers, and characterized them for their ability neutralize ricin in vitro and in vivo. We demonstrate that the VHH heterodimers, but not homodimers were able to completely protect mice against ricin challenge, even though the two classes of antibodies (heterodimers and homodimers) had virtually identical affinities for ricin holotoxin and similar IC50 values in a Vero cell cytotoxicity assay. The VHH heterodimers did differ from the homodimers in their ability to promote toxin aggregation in solution, as revealed through analytical ultracentrifugation. Moreover, the VHH heterodimers that were most effective at promoting ricin aggregation in solution were also the most effective at blocking ricin attachment to cell surfaces. Collectively, these data suggest that heterodimeric VHH-based neutralizing agents may function through the formation of antibody-toxin complexes that are impaired in their ability to access host cell receptors.
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Affiliation(s)
- Cristina Herrera
- From the Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York 12208, the Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York 12201, and
| | - Jacqueline M Tremblay
- the Department of Infectious Disease and Global Health, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachuetts 01536
| | - Charles B Shoemaker
- the Department of Infectious Disease and Global Health, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachuetts 01536
| | - Nicholas J Mantis
- From the Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York 12208, the Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York 12201, and
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