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Yu L, Chang H, Xie W, Zheng Y, Yang L, Wu Q, Bu F, Zhu Y, Xie Y, Pan G, Lan K, Deng Q. Manganese is a potent inducer of lysosomal activity that inhibits de novo HBV infection. PLoS Pathog 2025; 21:e1012800. [PMID: 39746094 PMCID: PMC11694974 DOI: 10.1371/journal.ppat.1012800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2024] [Accepted: 12/02/2024] [Indexed: 01/04/2025] Open
Abstract
Sodium taurocholate co-transporting polypeptide (NTCP) has been identified as an entry receptor for hepatitis B virus (HBV), but the molecular events of the viral post-endocytosis steps remain obscure. In this study, we discovered that manganese (Mn) could strongly inhibit HBV infection in NTCP-reconstituted HepG2 cells without affecting viral replication. We therefore profiled the antiviral effects of Mn2+ in an attempt to elucidate the regulatory mechanisms involved in early HBV infection. Intriguingly, Mn2+ conspicuously stimulated lysosomal activity, as evidenced by hyperactivation of mTORC1 and increased endo/lysosomal acidity. After HBV-triggered internalization, the NTCP receptor was sorted to late endosomal compartments by the ESCRT machinery in concert with the invading virion. The establishment of HBV infection was found to be independent of lysosomal fusion-driven late endosome maturation; Mn2+-induced lysosomal hyperfunction virtually impaired infection, suggesting that virions may gain cytosolic access directly from late endosomes. In contrast, suppression of lysosomal activity substantially enhanced HBV infection. Prolonged mTORC1 inactivation facilitated viral infection by depleting lysosomes and accelerating endocytic transport of virions. Notably, treatment with the natural steroidal alkaloid tomatidine recapitulated the effects of Mn2+ in stimulating lysosomal activity and exhibited potent anti-HBV activity in HepG2-NTCP cells and in proliferating human hepatocyte organoids. These findings provide new insights into the post-endocytosis events of HBV infection. The negative regulation of early HBV infection by endo/lysosomal activity makes it a promising target for antiviral therapies.
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Affiliation(s)
- Lin Yu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Hao Chang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Wentao Xie
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Shanghai, China
| | - Yuan Zheng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Le Yang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Qiong Wu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Fan Bu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Yuanfei Zhu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Youhua Xie
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
| | - Guoyu Pan
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ke Lan
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Qiang Deng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, Fudan University, Shanghai, China
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2
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Ferrari V, Tedesco B, Cozzi M, Chierichetti M, Casarotto E, Pramaggiore P, Cornaggia L, Mohamed A, Patelli G, Piccolella M, Cristofani R, Crippa V, Galbiati M, Poletti A, Rusmini P. Lysosome quality control in health and neurodegenerative diseases. Cell Mol Biol Lett 2024; 29:116. [PMID: 39237893 PMCID: PMC11378602 DOI: 10.1186/s11658-024-00633-2] [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: 04/12/2024] [Accepted: 08/13/2024] [Indexed: 09/07/2024] Open
Abstract
Lysosomes are acidic organelles involved in crucial intracellular functions, including the degradation of organelles and protein, membrane repair, phagocytosis, endocytosis, and nutrient sensing. Given these key roles of lysosomes, maintaining their homeostasis is essential for cell viability. Thus, to preserve lysosome integrity and functionality, cells have developed a complex intracellular system, called lysosome quality control (LQC). Several stressors may affect the integrity of lysosomes, causing Lysosomal membrane permeabilization (LMP), in which membrane rupture results in the leakage of luminal hydrolase enzymes into the cytosol. After sensing the damage, LQC either activates lysosome repair, or induces the degradation of the ruptured lysosomes through autophagy. In addition, LQC stimulates the de novo biogenesis of functional lysosomes and lysosome exocytosis. Alterations in LQC give rise to deleterious consequences for cellular homeostasis. Specifically, the persistence of impaired lysosomes or the malfunctioning of lysosomal processes leads to cellular toxicity and death, thereby contributing to the pathogenesis of different disorders, including neurodegenerative diseases (NDs). Recently, several pieces of evidence have underlined the importance of the role of lysosomes in NDs. In this review, we describe the elements of the LQC system, how they cooperate to maintain lysosome homeostasis, and their implication in the pathogenesis of different NDs.
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Affiliation(s)
- Veronica Ferrari
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Barbara Tedesco
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Marta Cozzi
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Marta Chierichetti
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Elena Casarotto
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Paola Pramaggiore
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Laura Cornaggia
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Ali Mohamed
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Guglielmo Patelli
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Margherita Piccolella
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Riccardo Cristofani
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Valeria Crippa
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Mariarita Galbiati
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
| | - Angelo Poletti
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy.
| | - Paola Rusmini
- Dipartimento di Scienze Farmacologiche e Biomolecolari "Rodolfo Paoletti", Università degli Studi di Milano, Dipartimento Di Eccellenza, 2018-2027, Milan, Italy
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3
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Sakai M, Ohnishi K, Masuda M, Harumoto E, Fukuda T, Ohnishi A, Ishii S, Ohminami H, Yamanaka-Okumura H, Ohashi K, Itakura E, Horikawa K, Yonemura S, Hara T, Taketani Y. Modulations of the mTORC2-GATA3 axis by an isorhamnetin activated endosomal-lysosomal system of the J774.1 macrophage-like cell line. J Clin Biochem Nutr 2024; 75:24-32. [PMID: 39070537 PMCID: PMC11273268 DOI: 10.3164/jcbn.24-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 03/12/2024] [Indexed: 07/30/2024] Open
Abstract
The endosomal-lysosomal system represents a crucial degradation pathway for various extracellular substances, and its dysfunction is linked to cardiovascular and neurodegenerative diseases. This degradation process involves multiple steps: (1) the uptake of extracellular molecules, (2) transport of cargos to lysosomes, and (3) digestion by lysosomal enzymes. While cellular uptake and lysosomal function are reportedly regulated by the mTORC1-TFEB axis, the key regulatory signal for cargo transport remains unclear. Notably, our previous study discovered that isorhamnetin, a dietary flavonoid, enhances endosomal-lysosomal proteolysis in the J774.1 cell line independently of the mTORC1-TFEB axis. This finding suggests the involvement of another signal in the mechanism of isorhamnetin. This study analyzes the molecular mechanism of isorhamnetin using transcriptome analysis and reveals that the transcription factor GATA3 plays a critical role in enhanced endosomal-lysosomal degradation. Our data also demonstrate that mTORC2 regulates GATA3 nuclear translocation, and the mTORC2-GATA3 axis alters endosomal formation and maturation, facilitating the efficient transport of cargos to lysosomes. This study suggests that the mTORC2-GATA3 axis might be a novel target for the degradation of abnormal substances.
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Affiliation(s)
- Maiko Sakai
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Kohta Ohnishi
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Masashi Masuda
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Erika Harumoto
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Teppei Fukuda
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Aika Ohnishi
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Shunsuke Ishii
- Department of Biology, Graduate School of Science and Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8555, Japan
| | - Hirokazu Ohminami
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Hisami Yamanaka-Okumura
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
- Department of Food Science and Nutrition, Doshisha Women College of Liberal Arts, Teramachi-Nishi-iru, Imadegawa-Kamigyo-ku, Kyoto 602-0893, Japan
| | - Kazuto Ohashi
- Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-cho, Maebashi-shi, Gunma 371-8512, Japan
| | - Eisuke Itakura
- Department of Biology, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8555, Japan
| | - Kazuki Horikawa
- Department of Optical Imaging, Advanced Research Promotion Center, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
| | - Shigenobu Yonemura
- Department of Cell Biology, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
- Laboratory for Ultrastructural Research, Riken Center for Biosystems Dynamics Research, 2-2-3 Minatojimaminami-machi, Chuo-ku, Kobe-shi, Hyogo 650-0047, Japan
| | - Taichi Hara
- Laboratory of Food and Life Science, Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa-shi, Saitama 359-1192, Japan
| | - Yutaka Taketani
- Department of Clinical Nutrition and Food Management, Institute of Biomedical Sciences, Tokushima University Graduate School of Medical Nutrition, 3-18-15 Kuramoto-cho, Tokushima-shi, Tokushima 770-8503, Japan
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4
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Naslavsky N, Caplan S. Receptor-mediated internalization promotes increased endosome size and number in a RAB4- and RAB5-dependent manner. Eur J Cell Biol 2023; 102:151339. [PMID: 37423034 PMCID: PMC10585956 DOI: 10.1016/j.ejcb.2023.151339] [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: 05/09/2023] [Revised: 06/26/2023] [Accepted: 07/05/2023] [Indexed: 07/11/2023] Open
Abstract
Despite their significance in receptor-mediated internalization and continued signal transduction in cells, early/sorting endosomes (EE/SE) remain incompletely characterized, with many outstanding questions that surround the dynamics of their size and number. While several studies have reported increases in EE/SE size and number resulting from endocytic events, few studies have addressed such dynamics in a methodological and quantitative manner. Herein we apply quantitative fluorescence microscopy to measure the size and number of EE/SE upon internalization of two different ligands: transferrin and epidermal growth factor. Additionally, we used siRNA knock-down to determine the involvement of 5 different endosomal RAB proteins (RAB4, RAB5, RAB8A, RAB10 and RAB11A) in EE/SE dynamics. Our study provides new information on the dynamics of endosomes during endocytosis, an important reference for researchers studying receptor-mediated internalization and endocytic events.
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Affiliation(s)
- Naava Naslavsky
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Steve Caplan
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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5
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Li Z, Liu J, Ballard K, Liang C, Wang C. Low-dose albumin-coated gold nanorods induce intercellular gaps on vascular endothelium by causing the contraction of cytoskeletal actin. J Colloid Interface Sci 2023; 649:844-854. [PMID: 37390532 DOI: 10.1016/j.jcis.2023.06.154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/17/2023] [Accepted: 06/22/2023] [Indexed: 07/02/2023]
Abstract
Cytotoxicity of nanoparticles, typically evaluated by biochemical-based assays, often overlook the cellular biophysical properties such as cell morphology and cytoskeletal actin, which could serve as more sensitive indicators for cytotoxicity. Here, we demonstrate that low-dose albumin-coated gold nanorods (HSA@AuNRs), although being considered noncytotoxic in multiple biochemical assays, can induce intercellular gaps and enhance the paracellular permeability between human aortic endothelial cells (HAECs). The formation of intercellular gaps can be attributed to the changed cell morphology and cytoskeletal actin structures, as validated at the monolayer and single cell levels using fluorescence staining, atomic force microscopy, and super-resolution imaging. Molecular mechanistic study shows the caveolae-mediated endocytosis of HSA@AuNRs induces the calcium influx and activates actomyosin contraction in HAECs. Considering the important roles of endothelial integrity/dysfunction in various physiological/pathological conditions, this work suggests a potential adverse effect of albumin-coated gold nanorods on the cardiovascular system. On the other hand, this work also offers a feasible way to modulate the endothelial permeability, thus promoting drug and nanoparticle delivery across the endothelium.
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Affiliation(s)
- Zhengqiang Li
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Jinyuan Liu
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Katherine Ballard
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Chao Liang
- Department of Anesthesiology, Zhongshan Hospital (Xiamen) Fudan University, Xiamen 361015, China; Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Congzhou Wang
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA.
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6
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Inhibition of lipid kinase PIKfyve reveals a role for phosphatase Inpp4b in the regulation of PI(3)P-mediated lysosome dynamics through VPS34 activity. J Biol Chem 2022; 298:102187. [PMID: 35760104 PMCID: PMC9304791 DOI: 10.1016/j.jbc.2022.102187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 06/13/2022] [Accepted: 06/15/2022] [Indexed: 11/21/2022] Open
Abstract
Lysosome membranes contain diverse phosphoinositide (PtdIns) lipids that coordinate lysosome function and dynamics. The PtdIns repertoire on lysosomes is tightly regulated by the actions of diverse PtdIns kinases and phosphatases; however, specific roles for PtdIns in lysosomal functions and dynamics are currently unclear and require further investigation. It was previously shown that PIKfyve, a lipid kinase that synthesizes PtdIns(3,5)P2 from PtdIns(3)P, controls lysosome "fusion-fission" cycle dynamics, autophagosome turnover, and endocytic cargo delivery. Furthermore, INPP4B, a PtdIns 4-phosphatase that hydrolyzes PtdIns(3,4)P2 to form PtdIns(3)P, is emerging as a cancer-associated protein with roles in lysosomal biogenesis and other lysosomal functions. Here, we investigated the consequences of disrupting PIKfyve function in Inpp4b-deficient mouse embryonic fibroblasts. Through confocal fluorescence imaging, we observed the formation of massively enlarged lysosomes, accompanied by exacerbated reduction of endocytic trafficking, disrupted lysosome fusion-fission dynamics, and inhibition of autophagy. Finally, HPLC scintillation quantification of 3H-myo-inositol labelled phosphoinositides and phosphoinositide immunofluorescence staining, we observed that lysosomal PtdIns(3)P levels were significantly elevated in Inpp4b-deficient cells due to the hyperactivation of phosphatidylinositol 3-kinase catalytic subunit VPS34 enzymatic activity. In conclusion, our study identifies a novel signaling axis that maintains normal lysosomal homeostasis and dynamics, which includes the catalytic functions of Inpp4b, PIKfyve, and VPS34.
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7
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Lee K, Jung I, Odom TW. Delivery Order of Nanoconstructs Affects Intracellular Trafficking by Endosomes. J Am Chem Soc 2022; 144:5274-5279. [PMID: 35302362 DOI: 10.1021/jacs.2c02276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This paper reports how the endosomal pathways of nanoparticle (NP) constructs with different surface curvatures are affected by their order of delivery. Sequential incubation of cytosine-phosphate-guanine (CpG)-conjugated spiky and spherical gold NPs with macrophages resulted in different nanoconstruct ratios at the interior edges of endosomes. Application of spiky NPs after spherical NPs accelerated the formation of late-stage endosomes and resulted in larger endosomes, and the spherical NPs were enclosed by the spiky NPs. In contrast, the reverse incubation order produced an asymmetric distribution of the two nanoconstruct shapes in smaller endosomes. Macrophages with a higher proportion of the enclosed spherical NPs as well as a larger ratio of spiky to spherical NPs at the endosomal edge showed enhanced toll-like receptor 9 activation and secretion of proinflammatory cytokines and chemokines. Our results indicate that the subcellular trafficking of targeting nanoconstructs by vesicles is affected by both the delivery order and the endosomal distribution. Our study also establishes a new approach for nanoscale monitoring of intracellular therapeutics delivery with conventional electron microscopy.
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Affiliation(s)
- Kwahun Lee
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Insub Jung
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Teri W Odom
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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8
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Saffi GT, Tang E, Mamand S, Inpanathan S, Fountain A, Salmena L, Botelho RJ. Reactive oxygen species prevent lysosome coalescence during PIKfyve inhibition. PLoS One 2021; 16:e0259313. [PMID: 34813622 PMCID: PMC8610251 DOI: 10.1371/journal.pone.0259313] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/16/2021] [Indexed: 11/19/2022] Open
Abstract
Lysosomes are terminal, degradative organelles of the endosomal pathway that undergo repeated fusion-fission cycles with themselves, endosomes, phagosomes, and autophagosomes. Lysosome number and size depends on balanced fusion and fission rates. Thus, conditions that favour fusion over fission can reduce lysosome numbers while enlarging their size. Conversely, favouring fission over fusion may cause lysosome fragmentation and increase their numbers. PIKfyve is a phosphoinositide kinase that generates phosphatidylinositol-3,5-bisphosphate to modulate lysosomal functions. PIKfyve inhibition causes an increase in lysosome size and reduction in lysosome number, consistent with lysosome coalescence. This is thought to proceed through reduced lysosome reformation and/or fission after fusion with endosomes or other lysosomes. Previously, we observed that photo-damage during live-cell imaging prevented lysosome coalescence during PIKfyve inhibition. Thus, we postulated that lysosome fusion and/or fission dynamics are affected by reactive oxygen species (ROS). Here, we show that ROS generated by various independent mechanisms all impaired lysosome coalescence during PIKfyve inhibition and promoted lysosome fragmentation during PIKfyve re-activation. However, depending on the ROS species or mode of production, lysosome dynamics were affected distinctly. H2O2 impaired lysosome motility and reduced lysosome fusion with phagosomes, suggesting that H2O2 reduces lysosome fusogenecity. In comparison, inhibitors of oxidative phosphorylation, thiol groups, glutathione, or thioredoxin, did not impair lysosome motility but instead promoted clearance of actin puncta on lysosomes formed during PIKfyve inhibition. Additionally, actin depolymerizing agents prevented lysosome coalescence during PIKfyve inhibition. Thus, we discovered that ROS can generally prevent lysosome coalescence during PIKfyve inhibition using distinct mechanisms depending on the type of ROS.
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Affiliation(s)
- Golam T. Saffi
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Evan Tang
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Sami Mamand
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Polytechnic Research Center, Erbil Polytechnic University, Kurdistan Regional Government, Erbil, Kurdistan
| | - Subothan Inpanathan
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Aaron Fountain
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Leonardo Salmena
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Roberto J. Botelho
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
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Liu J, Kang L, Ratnayake I, Ahrenkiel P, Smith S, Wang C. Targeting cancer cell adhesion molecule, CD146, with low-dose gold nanorods and mild hyperthermia disrupts actin cytoskeleton and cancer cell migration. J Colloid Interface Sci 2021; 601:556-569. [PMID: 34090032 PMCID: PMC8349892 DOI: 10.1016/j.jcis.2021.05.144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/10/2021] [Accepted: 05/23/2021] [Indexed: 12/16/2022]
Abstract
Cluster of differentiation 146 (CD146), a cancer cell adhesion molecule, is over-expressed on the surfaces of melanoma, breast, ovarian, and prostate cancer cells, and its high expression indicates the migration tendency of these cancer cells and poor patient prognosis. Here, we hypothesize that targeting the CD146 with low-dose gold nanorods combined with mild hyperthermia can stop the migration of these cancer cells. Two metastatic cancer cells including a melanoma and a breast cancer cell line are selected as the model systems. Cell migration assays show that the migration of both cell lines can be completely stopped by the treatment. Atomic force microscopy and super resolution fluorescence microscopy reveal the alterations of actin cytoskeleton and cell morphology correspond to the inhibited cell migration. Further mechanistic analysis indicates the treatment disrupts the actin cytoskeleton by a synergistic mechanism including depleting membrane CD146 and interfering ezrin-radixin-moesin phosphorylation. As a result, we believe targeting CD146 with low-dose gold nanorods and mild hyperthermia could be a versatile, effective, and safe approach for stopping cancer metastasis. More broadly, the concept of targeting cancer cell surface markers that connect the underlying actin cytoskeleton, offers enormous potential in treating cancer metastasis, which accounts for more than 90% of cancer-associated mortality.
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Affiliation(s)
- Jinyuan Liu
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA
| | - Lin Kang
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA
| | - Ishara Ratnayake
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA
| | - Phil Ahrenkiel
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA
| | - Steve Smith
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA
| | - Congzhou Wang
- Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, 501 East Saint Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 East Saint Joseph Street, Rapid City, SD 57701, USA.
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10
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Fountain A, Inpanathan S, Alves P, Verdawala MB, Botelho RJ. Phagosome maturation in macrophages: Eat, digest, adapt, and repeat. Adv Biol Regul 2021; 82:100832. [PMID: 34717137 DOI: 10.1016/j.jbior.2021.100832] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/06/2021] [Indexed: 11/30/2022]
Abstract
Phagocytosis is a dynamic process that requires an intricate interplay between phagocytic receptors, membrane lipids, and numerous signalling proteins and their effectors, to coordinate the engulfment of a bound particle. These particles are diverse in their physico-chemical properties such as size and shape and include bacteria, fungi, apoptotic cells, living tumour cells, and abiotic particles. Once engulfed, these particles are enclosed within a phagosome, which undergoes a striking transformation referred to as phagosome maturation, which will ultimately lead to the processing and degradation of the enclosed particulate. In this review, we focus on recent advancements in phagosome maturation in macrophages, highlighting new discoveries and emerging themes. Such advancements include identification of new GTPases and their effectors and the intricate spatio-temporal dynamics of phosphoinositides in governing phagosome maturation. We then explore phagosome fission and recycling, the emerging role of membrane contact sites, and delve into mechanisms of phagosome resolution to recycle and reform lysosomes. We further illustrate how phagosome maturation is context-dependent, subject to the type of particle, phagocytic receptors, the phagocytes and their state of activation during phagocytosis. Lastly, we discuss how phagosomes serve as signalling platforms to help phagocytes adapt to their environmental conditions. Overall, this review aims to cover recent findings, identify emerging themes, and highlight current challenges and directions to improve our understanding of phagosome maturation in macrophages.
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Affiliation(s)
- Aaron Fountain
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada; Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada
| | - Subothan Inpanathan
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada; Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada
| | - Patris Alves
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada; Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada
| | - Munira B Verdawala
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada
| | - Roberto J Botelho
- Department of Chemistry and Biology and Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada; Graduate Program in Molecular Science, Ryerson University, Toronto, Ontario, M5B2K3, Canada.
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11
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Skjeldal FM, Haugen LH, Mateus D, Frei DM, Rødseth AV, Hu X, Bakke O. De novo formation of early endosomes during Rab5-to-Rab7a transition. J Cell Sci 2021; 134:237792. [PMID: 33737317 PMCID: PMC8106955 DOI: 10.1242/jcs.254185] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 02/18/2021] [Indexed: 02/06/2023] Open
Abstract
Rab5 and Rab7a are the main determinants of early and late endosomes and are important regulators of endosomal progression. The transport from early endosomes to late endosome seems to be regulated through an endosomal maturation switch, where Rab5 is gradually exchanged by Rab7a on the same endosome. Here, we provide new insight into the mechanism of endosomal maturation, for which we have discovered a stepwise Rab5 detachment, sequentially regulated by Rab7a. The initial detachment of Rab5 is Rab7a independent and demonstrates a diffusion-like first-phase exchange between the cytosol and the endosomal membrane, and a second phase, in which Rab5 converges into specific domains that detach as a Rab5 indigenous endosome. Consequently, we show that early endosomal maturation regulated through the Rab5-to-Rab7a switch induces the formation of new fully functional Rab5-positive early endosomes. Progression through stepwise early endosomal maturation regulates the direction of transport and, concomitantly, the homeostasis of early endosomes. Highlighted Article: A crucial step in endosomal maturation is the exchange of Rab5 with Rab7a, and we show that this two-phase exchange is finalized by the formation of Rab5-positive early endosomes.
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Affiliation(s)
| | | | - Duarte Mateus
- Department of Biosciences, University of Oslo, 0371 Oslo, Norway
| | - Dominik M Frei
- Department of Biosciences, University of Oslo, 0371 Oslo, Norway
| | - Anna Vik Rødseth
- Department of Biosciences, University of Oslo, 0371 Oslo, Norway
| | - Xian Hu
- Department of Biosciences, University of Oslo, 0371 Oslo, Norway
| | - Oddmund Bakke
- Department of Biosciences, University of Oslo, 0371 Oslo, Norway
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12
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Fauzyah Y, Ono C, Torii S, Anzai I, Suzuki R, Izumi T, Morioka Y, Maeda Y, Okamoto T, Fukuhara T, Matsuura Y. Ponesimod suppresses hepatitis B virus infection by inhibiting endosome maturation. Antiviral Res 2020; 186:104999. [PMID: 33346055 DOI: 10.1016/j.antiviral.2020.104999] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 12/11/2022]
Abstract
The discovery of novel antivirals to treat hepatitis B virus (HBV) infection is urgently needed, as the currently available drugs mainly target viral proteins at replication step, whereas host factors also play significant roles in HBV infection. Although numerous studies have reported candidate drugs for HBV treatment, there remains a need to find a new drug that may target other steps of the HBV life cycle. In this study, by drug screening of a 533 G-protein-coupled receptors (GPCRs)-associated compound library, we identified ponesimod, a selective agonist of sphingosine-1-phosphate receptor 1 (S1P1), as a drug candidate for the suppression of HBV infection. However, the anti-HBV effect of ponesimod is independent of S1P1 and other sphingosine-1-phosphate receptors (S1PRs). Treatment with ponesimod at an early step of infection but not at a post-entry step significantly reduced the HBV relaxed circular DNA (rcDNA) level in a dose-dependent manner. Ponesimod treatment did not inhibit attachment, binding, or internalization of HBV particles via endocytosis through an interaction with sodium taurocholate cotransporting polypeptide (NTCP) or epidermal growth factor receptor (EGFR). Importantly, during the transportation of HBV particles to the nucleus, co-localization of HBV with early endosomes but not with late endosomes and lysosomes was induced by the treatment with ponesimod, suggesting that ponesimod interferes with the conversion of early endosomes to late endosomes without significant damage to cellular growth. Conclusion: Ponesimod is a promising anti-HBV drug targeting the endosome maturation of HBV. This finding can be applied to the development of novel antivirals that target the trafficking pathway of HBV particles.
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Affiliation(s)
- Yuzy Fauzyah
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Chikako Ono
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Shiho Torii
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Itsuki Anzai
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Rigel Suzuki
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Takuma Izumi
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Yuhei Morioka
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Yusuke Maeda
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Toru Okamoto
- Institute for Advanced Co-Creation Studies, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Takasuke Fukuhara
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan.
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13
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GSK-3-TSC axis governs lysosomal acidification through autophagy and endocytic pathways. Cell Signal 2020; 71:109597. [DOI: 10.1016/j.cellsig.2020.109597] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 03/06/2020] [Accepted: 03/06/2020] [Indexed: 12/16/2022]
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14
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Arienti S, Barth ND, Dorward DA, Rossi AG, Dransfield I. Regulation of Apoptotic Cell Clearance During Resolution of Inflammation. Front Pharmacol 2019; 10:891. [PMID: 31456686 PMCID: PMC6701246 DOI: 10.3389/fphar.2019.00891] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 07/15/2019] [Indexed: 01/17/2023] Open
Abstract
Programmed cell death (apoptosis) has an important role in the maintenance of tissue homeostasis as well as the progression and ultimate resolution of inflammation. During apoptosis, the cell undergoes morphological and biochemical changes [e.g., phosphatidylserine (PtdSer) exposure, caspase activation, changes in mitochondrial membrane potential and DNA cleavage] that act to shut down cellular function and mark the cell for phagocytic clearance. Tissue phagocytes bind and internalize apoptotic cells, bodies, and vesicles, providing a mechanism for the safe disposal of apoptotic material. Phagocytic removal of apoptotic cells before they undergo secondary necrosis reduces the potential for bystander damage to adjacent tissue and importantly initiates signaling pathways within the phagocytic cell that act to dampen inflammation. In a pathological context, excessive apoptosis or failure to clear apoptotic material results in secondary necrosis with the release of pro-inflammatory intracellular contents. In this review, we consider some of the mechanisms by which phagocytosis of apoptotic cells can be controlled. We suggest that matching apoptotic cell load with the capacity for apoptotic cell clearance within tissues may be important for therapeutic strategies that target the apoptotic process for treatment of inflammatory disease.
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Affiliation(s)
- Simone Arienti
- Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Nicole D Barth
- Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - David A Dorward
- Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Adriano G Rossi
- Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Ian Dransfield
- Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
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15
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Elmogy M, Mohamed AA, Tufail M, Uno T, Takeda M. Molecular and functional characterization of the American cockroach, Periplaneta americana, Rab5: the first exopterygotan low molecular weight ovarian GTPase during oogenesis. INSECT SCIENCE 2018; 25:751-764. [PMID: 28548451 DOI: 10.1111/1744-7917.12485] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 03/22/2017] [Accepted: 04/19/2017] [Indexed: 06/07/2023]
Abstract
The small Rab GTPases are key regulators of membrane vesicle trafficking. Ovaries of Periplaneta americana (Linnaeus) (Blattodea: Blattidae) have small molecular weight GTP/ATP-binding proteins during early and late vitellogenic periods of oogenesis. However, the identification and characterization of the detected proteins have not been yet reported. Herein, we cloned a cDNA encoding Rab5 from the American cockroach, P. americana, ovaries (PamRab5). It comprises 796 bp, encoding a protein of 213 amino acid residues with a predicted molecular weight of 23.5 kDa. PamRab5 exists as a single-copy gene in the P. americana genome, as revealed by Southern blot analysis. An approximate 2.6 kb ovarian mRNA was transcribed especially at high levels in the previtellogenic ovaries, detected by Northern blot analysis. The muscle and head tissues also showed high levels of PamRab5 transcript. PamRab5 protein was localized, via immunofluorescence labeling, to germline-derived cells of the oocytes, very early during oocyte differentiation. Immunoblotting detected a ∼25 kDa signal as a membrane-associated form revealed after application of detergent in the extraction buffer, and 23 kDa as a cytosolic form consistent with the predicted molecular weight from amino acid sequence in different tissues including ovary, muscles and head. The PamRab5 during late vitellogenic periods is required to regulate the endocytotic machinery during oogenesis in this cockroach. This is the first report on Rab5 from a hemimetabolan, and presents an inaugural step in probing the molecular premises of insect oocyte endocytotic trafficking important for oogenesis and embryonic development.
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Affiliation(s)
- Mohamed Elmogy
- Department of Entomology, Faculty of Science, Cairo University, Orman, Giza, Egypt
| | - Amr A Mohamed
- Department of Entomology, Faculty of Science, Cairo University, Orman, Giza, Egypt
| | - Muhammad Tufail
- Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, Japan
| | - Tomohide Uno
- Laboratory of Biological Chemistry, Faculty of Agriculture, Department of Biofunctional Chemistry, Kobe University, Nada-ku, Hyogo, Japan
| | - Makio Takeda
- Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, Japan
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16
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Alcantara CDL, de Souza W, da Cunha E Silva NL. Tridimensional Electron Microscopy Analysis of the Early Endosomes and Endocytic Traffic in Trypanosoma cruzi Epimastigotes. Protist 2018; 169:887-910. [PMID: 30447618 DOI: 10.1016/j.protis.2018.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 08/25/2018] [Accepted: 09/24/2018] [Indexed: 02/04/2023]
Abstract
Trypanosoma cruzi epimastigotes internalize macromolecules avidly by endocytosis. Previously, we identified a tubule-vesicular network likely to correspond to the early-endosomes. However, a detailed ultrastructural characterization of these endosomes was missing. Here, we combined endocytosis assays with ultrastructural data from high-resolution electron microscopy to produce a 3D analysis of epimastigote endosomes and their interactions with endocytic organelles. We showed that endocytic cargo was found in carrier vesicles budding from the cytopharynx. These vesicles appeared to fuse with a tubule-vesicular network of early endosomes identified by ultrastructural features including the presence of intermembrane invaginations and coated membrane sections. Within the posterior region of the cell, endosomes localized preferentially on the side nearest to the cytopharynx microtubules. At 4°C, cargo accumulated at a shortened cytopharynx, and subsequent temperature shift to 12°C led to slow cargo delivery to endosomes and, later, to reservosomes. Bridges between reservosomes and endosomes resemble heterotypic fusion. Reservosomes are excluded from the posterior end of the cell, with no preferential cargo delivery to reservosomes closer to the nucleus. Our 3D analysis indicates that epimastigotes accomplish high-speed endocytic traffic by cargo transfer to a bona fide early-endosome and then directly from endosomes to reservosomes, via multiple and simultaneous heterotypic fusion events.
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Affiliation(s)
- Carolina de Lima Alcantara
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; Núcleo de Biologia Estrutural e Bioimagens (CENABIO) - Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Biomagens (INBEB), Rio de Janeiro 21941-902, RJ, Brazil.
| | - Wanderley de Souza
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; Núcleo de Biologia Estrutural e Bioimagens (CENABIO) - Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Biomagens (INBEB), Rio de Janeiro 21941-902, RJ, Brazil
| | - Narcisa L da Cunha E Silva
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; Núcleo de Biologia Estrutural e Bioimagens (CENABIO) - Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Biomagens (INBEB), Rio de Janeiro 21941-902, RJ, Brazil
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17
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Yan Q, Lin M, Huang W, Teymournejad O, Johnson JM, Hays FA, Liang Z, Li G, Rikihisa Y. Ehrlichia type IV secretion system effector Etf-2 binds to active RAB5 and delays endosome maturation. Proc Natl Acad Sci U S A 2018; 115:E8977-E8986. [PMID: 30181274 PMCID: PMC6156607 DOI: 10.1073/pnas.1806904115] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ehrlichia chaffeensis, an obligatory intracellular bacterium, infects monocytes/macrophages by sequestering a regulator of endosomal traffic, the small GTPase RAB5, on its membrane-bound inclusions to avoid routing to host-cell phagolysosomes. How RAB5 is sequestered on ehrlichial inclusions is poorly understood, however. We found that native Ehrlichia translocated factor-2 (Etf-2), a previously predicted effector of the Ehrlichia type IV secretion system, and recombinant Etf-2 (cloned into the Ehrlichia genome) are secreted into the host-cell cytoplasm and localize to ehrlichial inclusions. Ectopically expressed Etf-2-GFP also localized to inclusions and membranes of early endosomes marked with RAB5 and interacted with GTP-bound RAB5 but not with a GDP-bound RAB5. Etf-2, although lacking a RAB GTPase-activating protein (GAP) Tre2-Bub2-Cdc16 (TBC) domain, contains two conserved TBC domain motifs, namely an Arg finger and a Gln finger, and site-directed mutagenesis revealed that both Arg188 and Gln245 are required for Etf-2 localization to early endosomes. The yeast two-hybrid assay and microscale thermophoresis revealed that Etf-2 binds tightly to GTP-bound RAB5 but not to GDP-bound RAB5. However, Etf-2 lacks RAB5-specific GAP activity. Etf-2 localized to bead-containing phagosomes as well as endosomes containing beads coated with the C-terminal fragment of EtpE (entry-triggering protein of Ehrlichia), an Ehrlichia outer-membrane invasin, and significantly delayed RAB5 dissociation from and RAB7 localization to phagosomes/endosomes and RABGAP5 localization to endosomes. Thus, binding of Etf-2 to RAB5-GTP appears to delay RAB5 inactivation by impeding RABGAP5 localization to endosomes. This suggests a unique mechanism by which RAB5 is sequestered on ehrlichial inclusions to benefit bacterial survival and replication.
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Affiliation(s)
- Qi Yan
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210
| | - Mingqun Lin
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210
| | - Weiyan Huang
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210
| | - Omid Teymournejad
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210
| | - Jennifer M Johnson
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - Franklin A Hays
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - Zhimin Liang
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - Guangpu Li
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - Yasuko Rikihisa
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210;
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18
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Fuchs R, Stracke A, Holzmann V, Luschin-Ebengreuth G, Meier-Allard N, Ebner N, Lassacher TM, Absenger-Novak M, Fröhlich E, Schittmayer M, Cano Crespo S, Palacin M, Rinner B, Birner-Gruenberger R. Prazosin induced lysosomal tubulation interferes with cytokinesis and the endocytic sorting of the tumour antigen CD98hc. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:1211-1229. [PMID: 29909287 PMCID: PMC6070144 DOI: 10.1016/j.bbamcr.2018.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/28/2018] [Accepted: 06/12/2018] [Indexed: 11/29/2022]
Abstract
The quinazoline based drug prazosin (PRZ) is a potent inducer of apoptosis in human cancer cells. We recently reported that PRZ enters cells via endocytosis and induces tubulation of the endolysosomal system. In a proteomics approach aimed at identifying potential membrane proteins with binding affinity to quinazolines, we detected the oncoprotein CD98hc. We confirmed shuttling of CD98hc towards lysosomes and upregulation of CD98hc expression in PRZ treated cells. Gene knockout (KO) experiments revealed that endocytosis of PRZ still occurs in the absence of CD98hc - suggesting that PRZ does not enter the cell via CD98hc but misroutes the protein towards tubular lysosomes. Lysosomal tubulation interfered with completion of cytokinesis and provoked endoreplication. CD98hc KO cells showed reduced endoreplication capacity and lower sensitivity towards PRZ induced apoptosis than wild type cells. Thus, loss of CD98hc does not affect endocytosis of PRZ and lysosomal tubulation, but the ability for endoreplication and survival of cells. Furthermore, we found that glutamine, lysomototropic agents - namely chloroquine and NH4Cl - as well as inhibition of v-ATPase, interfere with the intracellular transport of CD98hc. In summary, our study further emphasizes lysosomes as target organelles to inhibit proliferation and to induce cell death in cancer. Most importantly, we demonstrate for the first time that the intracellular trafficking of CD98hc can be modulated by small molecules. Since CD98hc is considered as a potential drug target in several types of human malignancies, our study possesses translational significance suggesting, that old drugs are able to act on a novel target.
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Affiliation(s)
- Robert Fuchs
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria.
| | - Anika Stracke
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Viktoria Holzmann
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria; FH JOANNEUM - University of Applied Sciences, Alte Poststraße 149, 8020 Graz, Austria
| | - Gerfried Luschin-Ebengreuth
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Nathalie Meier-Allard
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Nadine Ebner
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Teresa Maria Lassacher
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Markus Absenger-Novak
- Centre for Medical Research, Medical University of Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Eleonore Fröhlich
- Centre for Medical Research, Medical University of Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Matthias Schittmayer
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria; Omics Center Graz, BioTechMed-Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Sara Cano Crespo
- Institute for Research in Biomedicine (IRB-Barcelona), Barcelona Institute of Science and Technology (BIST), Department of Biochemistry and Molecular Biomedicine, University of Barcelona, and CIBERER, Parc Científic de Barcelona. Baldiri I Reixac 10-12, 08028 Barcelona, Spain
| | - Manuel Palacin
- Institute for Research in Biomedicine (IRB-Barcelona), Barcelona Institute of Science and Technology (BIST), Department of Biochemistry and Molecular Biomedicine, University of Barcelona, and CIBERER, Parc Científic de Barcelona. Baldiri I Reixac 10-12, 08028 Barcelona, Spain
| | - Beate Rinner
- Biomedical Research, Medical University of Graz, Roseggerweg 48, 8036 Graz, Austria
| | - Ruth Birner-Gruenberger
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria; Omics Center Graz, BioTechMed-Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
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Choy CH, Saffi G, Gray MA, Wallace C, Dayam RM, Ou ZYA, Lenk G, Puertollano R, Watkins SC, Botelho RJ. Lysosome enlargement during inhibition of the lipid kinase PIKfyve proceeds through lysosome coalescence. J Cell Sci 2018; 131:jcs.213587. [PMID: 29661845 DOI: 10.1242/jcs.213587] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 04/10/2018] [Indexed: 01/07/2023] Open
Abstract
Lysosomes receive and degrade cargo from endocytosis, phagocytosis and autophagy. They also play an important role in sensing and instructing cells on their metabolic state. The lipid kinase PIKfyve generates phosphatidylinositol-3,5-bisphosphate to modulate lysosome function. PIKfyve inhibition leads to impaired degradative capacity, ion dysregulation, abated autophagic flux and a massive enlargement of lysosomes. Collectively, this leads to various physiological defects, including embryonic lethality, neurodegeneration and overt inflammation. The reasons for such drastic lysosome enlargement remain unclear. Here, we examined whether biosynthesis and/or fusion-fission dynamics contribute to swelling. First, we show that PIKfyve inhibition activates TFEB, TFE3 and MITF, enhancing lysosome gene expression. However, this did not augment lysosomal protein levels during acute PIKfyve inhibition, and deletion of TFEB and/or related proteins did not impair lysosome swelling. Instead, PIKfyve inhibition led to fewer but enlarged lysosomes, suggesting that an imbalance favouring lysosome fusion over fission causes lysosome enlargement. Indeed, conditions that abated fusion curtailed lysosome swelling in PIKfyve-inhibited cells.
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Affiliation(s)
- Christopher H Choy
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3.,The Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada, M5B2K3
| | - Golam Saffi
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3.,The Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada, M5B2K3
| | - Matthew A Gray
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3
| | - Callen Wallace
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Roya M Dayam
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3.,The Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada, M5B2K3
| | - Zhen-Yi A Ou
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3
| | - Guy Lenk
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rosa Puertollano
- Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, 50 South Drive, Building 50, Room 3537, Bethesda, MD 20892, USA
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Roberto J Botelho
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada, M5B2K3 .,The Graduate Program in Molecular Science, Ryerson University, Toronto, ON, Canada, M5B2K3
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Das A, Nag S, Mason AB, Barroso MM. Endosome-mitochondria interactions are modulated by iron release from transferrin. J Cell Biol 2016; 214:831-45. [PMID: 27646275 PMCID: PMC5037410 DOI: 10.1083/jcb.201602069] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 08/11/2016] [Indexed: 12/21/2022] Open
Abstract
Using superresolution and quantitative fluorescence microscopy, Das et al. have revealed that iron-transferrin–containing endosomes directly interact with mitochondria, facilitating iron transfer in epithelial cells. Their findings further enrich the repertoire of organelle–organelle direct interactions to accomplish a functional significance. Transient “kiss and run” interactions between endosomes containing iron-bound transferrin (Tf) and mitochondria have been shown to facilitate direct iron transfer in erythroid cells. In this study, we used superresolution three-dimensional (3D) direct stochastic optical reconstruction microscopy to show that Tf-containing endosomes directly interact with mitochondria in epithelial cells. We used live-cell time-lapse fluorescence microscopy, followed by 3D rendering, object tracking, and a distance transformation algorithm, to track Tf-endosomes and characterize the dynamics of their interactions with mitochondria. Quenching of iron sensor RDA-labeled mitochondria confirmed functional iron transfer by an interacting Tf-endosome. The motility of Tf-endosomes is significantly reduced upon interaction with mitochondria. To further assess the functional role of iron in the ability of Tf-endosomes to interact with mitochondria, we blocked endosomal iron release by using a Tf K206E/K534A mutant. Blocking intraendosomal iron release led to significantly increased motility of Tf-endosomes and increased duration of endosome–mitochondria interactions. Thus, intraendosomal iron regulates the kinetics of the interactions between Tf-containing endosomes and mitochondria in epithelial cells.
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Affiliation(s)
- Anupam Das
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208
| | - Sagarika Nag
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208
| | - Anne B Mason
- Department of Biochemistry, University of Vermont College of Medicine, Burlington, VT 05405
| | - Margarida M Barroso
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208
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Chaiyarit S, Singhto N, Thongboonkerd V. Calcium oxalate monohydrate crystals internalized into renal tubular cells are degraded and dissolved by endolysosomes. Chem Biol Interact 2015; 246:30-5. [PMID: 26748311 DOI: 10.1016/j.cbi.2015.12.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/04/2015] [Accepted: 12/29/2015] [Indexed: 01/24/2023]
Abstract
Interaction between calcium oxalate crystals and renal tubular cells has been recognized as one of the key mechanisms for kidney stone formation. While crystal adhesion and internalization have been extensively investigated, subsequent phenomena (i.e. crystal degradation and dissolution) remained poorly understood. To explore these mechanisms, we used fluorescein isothiocyanate (FITC)-labelled calcium oxalate monohydrate (COM) crystals (1000 μg/ml of crystals/culture medium) to confirm crystal internalization into MDCK (Type II) renal tubular cells after exposure to the crystals for 1 h and to trace the internalized crystals. Crystal size, intracellular and extracellular fluorescence levels were measured using a spectrofluorometer for up to 48 h after crystal internalization. Moreover, markers for early endosome (Rab5), late endosome (Rab7) and lysosome (LAMP-2) were examined by laser-scanning confocal microscopy. Fluorescence imaging and flow cytometry confirmed that FITC-labelled COM crystals were internalized into MDCK cells (14.83 ± 0.85%). The data also revealed a reduction of crystal size in a time-dependent manner. In concordance, intracellular and extracellular fluorescence levels were decreased and increased, respectively, indicating crystal degradation/dissolution inside the cells and the degraded products were eliminated extracellularly. Moreover, Rab5 and Rab7 were both up-regulated and were also associated with the up-regulated LAMP-2 to form large endolysosomes in the COM-treated cells at 16-h after crystal internalization. We demonstrate herein, for the first time, that COM crystals could be degraded/dissolved by endolysosomes inside renal tubular cells. These findings will be helpful to better understand the crystal fate and protective mechanism against kidney stone formation.
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Affiliation(s)
- Sakdithep Chaiyarit
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Center for Research in Complex Systems Sciences, Mahidol University, Bangkok, Thailand
| | - Nilubon Singhto
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Center for Research in Complex Systems Sciences, Mahidol University, Bangkok, Thailand
| | - Visith Thongboonkerd
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Center for Research in Complex Systems Sciences, Mahidol University, Bangkok, Thailand.
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de Araújo MEG, Lamberti G, Huber LA. Purification of Early and Late Endosomes. Cold Spring Harb Protoc 2015; 2015:pdb.top074443. [PMID: 26631131 DOI: 10.1101/pdb.top074443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Proteomic analysis of early and late endosomes has been constrained by the limited purity of the endosomal fractions that can be achieved by biochemical methods. Here we briefly review endocytic pathways, and then introduce fractionation strategies that have been used to improve the purity of isolated endosomes. In addition, we describe innovative proteomics analysis methods that have been shown to partially circumvent the limitations found in the enrichment steps.
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Affiliation(s)
- Mariana E G de Araújo
- Biocenter, Division of Cell Biology, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Giorgia Lamberti
- Biocenter, Division of Cell Biology, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Lukas A Huber
- Biocenter, Division of Cell Biology, Innsbruck Medical University, A-6020 Innsbruck, Austria
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23
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von Wangenheim D, Rosero A, Komis G, Šamajová O, Ovečka M, Voigt B, Šamaj J. Endosomal Interactions during Root Hair Growth. FRONTIERS IN PLANT SCIENCE 2015; 6:1262. [PMID: 26858728 PMCID: PMC4731515 DOI: 10.3389/fpls.2015.01262] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 12/24/2015] [Indexed: 05/21/2023]
Abstract
The dynamic localization of endosomal compartments labeled with targeted fluorescent protein tags is routinely followed by time lapse fluorescence microscopy approaches and single particle tracking algorithms. In this way trajectories of individual endosomes can be mapped and linked to physiological processes as cell growth. However, other aspects of dynamic behavior including endosomal interactions are difficult to follow in this manner. Therefore, we characterized the localization and dynamic properties of early and late endosomes throughout the entire course of root hair formation by means of spinning disc time lapse imaging and post-acquisition automated multitracking and quantitative analysis. Our results show differential motile behavior of early and late endosomes and interactions of late endosomes that may be specified to particular root hair domains. Detailed data analysis revealed a particular transient interaction between late endosomes-termed herein as dancing-endosomes-which is not concluding to vesicular fusion. Endosomes preferentially located in the root hair tip interacted as dancing-endosomes and traveled short distances during this interaction. Finally, sizes of early and late endosomes were addressed by means of super-resolution structured illumination microscopy (SIM) to corroborate measurements on the spinning disc. This is a first study providing quantitative microscopic data on dynamic spatio-temporal interactions of endosomes during root hair tip growth.
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Affiliation(s)
- Daniel von Wangenheim
- Department of Plant Cell Biology, Institute of Cellular and Molecular Botany, University of BonnBonn, Germany
| | - Amparo Rosero
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - George Komis
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Olga Šamajová
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Miroslav Ovečka
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
| | - Boris Voigt
- Department of Plant Cell Biology, Institute of Cellular and Molecular Botany, University of BonnBonn, Germany
| | - Jozef Šamaj
- Department of Cell Biology, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký UniversityOlomouc, Czech Republic
- *Correspondence: Jozef Šamaj
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24
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Gilberti RM, Knecht DA. Macrophages phagocytose nonopsonized silica particles using a unique microtubule-dependent pathway. Mol Biol Cell 2014; 26:518-29. [PMID: 25428990 PMCID: PMC4310742 DOI: 10.1091/mbc.e14-08-1301] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cells can take up particles by both opsonized and nonopsonized pathways. Silica and latex, but not zymosan, can be taken up by the nonopsonized pathway. Uptake of silica, but not latex, is toxic to macrophages. Nonopsonized phagocytosis is characterized and found to have key differences from the complement- and antibody-opsonized pathways. Silica inhalation leads to the development of the chronic lung disease silicosis. Macrophages are killed by uptake of nonopsonized silica particles, and this is believed to play a critical role in the etiology of silicosis. However, the mechanism of nonopsonized-particle uptake is not well understood. We compared the molecular events associated with nonopsonized- and opsonized-particle phagocytosis. Both Rac and RhoA GTPases are activated upon nonopsonized-particle exposure, whereas opsonized particles activate either Rac or RhoA. All types of particles quickly generate a PI(3,4,5)P3 and F-actin response at the particle attachment site. After formation of a phagosome, the events related to endolysosome-to-phagosome fusion do not significantly differ between the pathways. Inhibitors of tyrosine kinases, actin polymerization, and the phosphatidylinositol cascade prevent opsonized- and nonopsonized-particle uptake similarly. Inhibition of silica particle uptake prevents silica-induced cell death. Microtubule depolymerization abolished uptake of complement-opsonized and nonopsonized particles but not Ab-opsonized particles. Of interest, regrowth of microtubules allowed uptake of new nonopsonized particles but not ones bound to cells in the absence of microtubules. Although complement-mediated uptake requires macrophages to be PMA-primed, untreated cells phagocytose nonopsonized silica and latex. Thus it appears that nonopsonized-particle uptake is accomplished by a pathway with unique characteristics.
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Affiliation(s)
- Renée M Gilberti
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - David A Knecht
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
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25
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TLR-dependent phagosome tubulation in dendritic cells promotes phagosome cross-talk to optimize MHC-II antigen presentation. Proc Natl Acad Sci U S A 2014; 111:15508-13. [PMID: 25313083 DOI: 10.1073/pnas.1412998111] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Dendritic cells (DCs) phagocytose large particles like bacteria at sites of infection and progressively degrade them within maturing phagosomes. Phagosomes in DCs are also signaling platforms for pattern recognition receptors, such as Toll-like receptors (TLRs), and sites for assembly of cargo-derived peptides with major histocompatibility complex class II (MHC-II) molecules. Although TLR signaling from phagosomes stimulates presentation of phagocytosed antigens, the mechanisms underlying this enhancement and the cell surface delivery of MHC-II-peptide complexes from phagosomes are not known. We show that in DCs, maturing phagosomes extend numerous long tubules several hours after phagocytosis. Tubule formation requires an intact microtubule and actin cytoskeleton and MyD88-dependent phagosomal TLR signaling, but not phagolysosome formation or extensive proteolysis. In contrast to the tubules that emerge from endolysosomes after uptake of soluble ligands and TLR stimulation, the late-onset phagosomal tubules are not essential for delivery of phagosome-derived MHC-II-peptide complexes to the plasma membrane. Rather, tubulation promotes MHC-II presentation by enabling maximal cargo transfer among phagosomes that bear a TLR signature. Our data show that phagosomal tubules in DCs are functionally distinct from those that emerge from lysosomes and are unique adaptations of the phagocytic machinery that facilitate cargo exchange and antigen presentation among TLR-signaling phagosomes.
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26
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Leonoudakis D, Huang G, Akhavan A, Fata JE, Singh M, Gray JW, Muschler JL. Endocytic trafficking of laminin is controlled by dystroglycan and is disrupted in cancers. J Cell Sci 2014; 127:4894-903. [PMID: 25217627 DOI: 10.1242/jcs.152728] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The dynamic interactions between cells and basement membranes serve as essential regulators of tissue architecture and function in metazoans, and perturbation of these interactions contributes to the progression of a wide range of human diseases, including cancers. Here, we reveal the pathway and mechanism for the endocytic trafficking of a prominent basement membrane protein, laminin-111 (referred to here as laminin), and their disruption in disease. Live-cell imaging of epithelial cells revealed pronounced internalization of laminin into endocytic vesicles. Laminin internalization was receptor mediated and dynamin dependent, and laminin proceeded to the lysosome through the late endosome. Manipulation of laminin receptor expression revealed that the dominant regulator of laminin internalization is dystroglycan, a laminin receptor that is functionally perturbed in muscular dystrophies and in many cancers. Correspondingly, laminin internalization was found to be deficient in aggressive cancer cells displaying non-functional dystroglycan, and restoration of dystroglycan function strongly enhanced the endocytosis of laminin in both breast cancer and glioblastoma cells. These results establish previously unrecognized mechanisms for the modulation of cell-basement-membrane communication in normal cells and identify a profound disruption of endocytic laminin trafficking in aggressive cancer subtypes.
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Affiliation(s)
- Dmitri Leonoudakis
- California Pacific Medical Center Research Institute, 475 Brannan St., Suite 220, San Francisco, CA 94107, USA
| | - Ge Huang
- Biomedical Engineering Department, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Armin Akhavan
- California Pacific Medical Center Research Institute, 475 Brannan St., Suite 220, San Francisco, CA 94107, USA
| | - Jimmie E Fata
- Department of Biology, College of Staten Island, City University of New York, 2800 Victory Blvd, Staten Island, NY 10314, USA
| | - Manisha Singh
- California Pacific Medical Center Research Institute, 475 Brannan St., Suite 220, San Francisco, CA 94107, USA
| | - Joe W Gray
- Biomedical Engineering Department, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA Center for Spatial Systems Biomedicine, and Knight Cancer Institute, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - John L Muschler
- California Pacific Medical Center Research Institute, 475 Brannan St., Suite 220, San Francisco, CA 94107, USA Biomedical Engineering Department, Oregon Health and Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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Rangel-Filho A, Lazar J, Moreno C, Geurts A, Jacob HJ. Rab38 modulates proteinuria in model of hypertension-associated renal disease. J Am Soc Nephrol 2013; 24:283-92. [PMID: 23291471 DOI: 10.1681/asn.2012090927] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
We previously reported that the fawn-hooded hypertensive (FHH) rat is a natural Rab38 knockout, supported by a congenic animal (FHH.BN-Rab38) having less proteinuria than FHH animals. Because these congenic animals contain Brown Norway (BN) alleles for five other named genes; however, a causal role for Rab38 in the FHH phenotype remains uncertain. Here, we used transgenic and knockout models to validate Rab38 and to exclude other genes within the 1.5 Mb congenic region from involvement in causing the FHH phenotype. Transgenic rats homozygous for the wild-type Rab38 BN allele on the FHH background exhibited phenotypic rescue, having 43% lower proteinuria and 75% lower albuminuria than nontransgenic FHH littermates. Conversely, knockout of the Rab38 gene on the FHH.BN-Rab38 congenic line recapitulated a proteinuric phenotype indistinguishable from the FHH strain. In addition, in cultured proximal tubule LLC-PK1 cells, knockdown of Rab38 mRNA significantly decreased endocytosis of colloidal gold-coupled albumin, supporting the hypothesis that Rab38 modulates proteinuria through effects on tubular re-uptake and not by altering glomerular permeability. Taken together, these findings validate Rab38 as a gene having a causal role in determining the phenotype of the FHH rat, which models hypertension-associated renal disease. Furthermore, our data suggest that Rab38 affects urinary protein excretion via effects in the proximal tubule.
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Affiliation(s)
- Artur Rangel-Filho
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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28
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Ng EL, Gan BQ, Ng F, Tang BL. Rab GTPases regulating receptor trafficking at the late endosome-lysosome membranes. Cell Biochem Funct 2012; 30:515-23. [DOI: 10.1002/cbf.2827] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 02/07/2012] [Accepted: 03/09/2012] [Indexed: 02/05/2023]
Affiliation(s)
- Ee Ling Ng
- Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Bin Qi Gan
- Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Fanny Ng
- Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Bor Luen Tang
- Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
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29
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Uptake mechanisms of non-viral gene delivery. J Control Release 2012; 158:371-8. [DOI: 10.1016/j.jconrel.2011.09.093] [Citation(s) in RCA: 229] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 09/23/2011] [Indexed: 01/04/2023]
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Guimarães de Araújo ME, Huber LA, Stasyk T. Latex beads internalization and quantitative proteomics join forces to decipher the endosomal proteome. Expert Rev Proteomics 2011; 8:303-7. [PMID: 21679111 DOI: 10.1586/epr.11.27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The proteome analysis of endocytic compartments has been constrained by the limited purity of the organelle fractions obtained by current biochemical methods. Duclos and coworkers have developed a novel method to isolate highly purified endosomal organelles based on small latex beads internalization followed by gradient centrifugation and successfully combined it with a redundant peptide counting method to compare the relative abundance of proteins in organelles. The presence of bona fide markers in their respective subcellular organelles and the identification of several new endosomal-associated proteins, attested the applicability of their combinatory approach. Future applications of this strategy may deliver a comprehensive endosomal proteome chart: from the identification of the key players to the determination of time and signaling-dependent proteome changes. As a long-term perspective, such an approach may unveil new clues to the molecular mechanisms underlining human diseases associated with endosomal biogenesis defects.
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31
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Overmeyer JH, Young AM, Bhanot H, Maltese WA. A chalcone-related small molecule that induces methuosis, a novel form of non-apoptotic cell death, in glioblastoma cells. Mol Cancer 2011; 10:69. [PMID: 21639944 PMCID: PMC3118192 DOI: 10.1186/1476-4598-10-69] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 06/06/2011] [Indexed: 01/19/2023] Open
Abstract
Background Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Results Here we describe a novel chalcone-like molecule, 3-(2-methyl-1H- indol-3-yl)-1-(4-pyridinyl)-2-propen-1-one (MIPP) that induces cell death with the hallmarks of methuosis. MIPP causes rapid accumulation of vacuoles derived from macropinosomes, based on time-lapse microscopy and labeling with extracellular fluid phase tracers. Vacuolization can be blocked by the cholesterol-interacting compound, filipin, consistent with the origin of the vacuoles from non-clathrin endocytic compartments. Although the vacuoles rapidly acquire some characteristics of late endosomes (Rab7, LAMP1), they remain distinct from lysosomal and autophagosomal compartments, suggestive of a block at the late endosome/lysosome boundary. MIPP appears to target steps in the endosomal trafficking pathway involving Rab5 and Rab7, as evidenced by changes in the activation states of these GTPases. These effects are specific, as other GTPases (Rac1, Arf6) are unaffected by the compound. Cells treated with MIPP lose viability within 2-3 days, but their nuclei show no evidence of apoptotic changes. Inhibition of caspase activity does not protect the cells, consistent with a non-apoptotic death mechanism. U251 glioblastoma cells selected for temozolomide resistance showed sensitivity to MIPP-induced methuosis that was comparable to the parental cell line. Conclusions MIPP might serve as a prototype for new drugs that could be used to induce non-apoptotic death in cancers that have become refractory to agents that work through DNA damage and apoptotic mechanisms.
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Affiliation(s)
- Jean H Overmeyer
- Department of Biochemistry and Cancer Biology, University of Toledo College of Medicine, Toledo, Ohio, USA
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32
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Marion S, Hoffmann E, Holzer D, Le Clainche C, Martin M, Sachse M, Ganeva I, Mangeat P, Griffiths G. Ezrin promotes actin assembly at the phagosome membrane and regulates phago-lysosomal fusion. Traffic 2011; 12:421-37. [PMID: 21210911 DOI: 10.1111/j.1600-0854.2011.01158.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phagosome maturation is defined as the process by which phagosomes fuse sequentially with endosomes and lysosomes to acquire an acidic pH and hydrolases that degrade ingested particles. While the essential role of actin cytoskeleton remodeling during particle internalization is well established, its role during the later stages of phagosome maturation remains largely unknown. We have previously shown that purified mature phagosomes assemble F-actin at their membrane, and that the ezrin-radixin-moesin (ERM) proteins ezrin and moesin participate in this process. Moreover, we provided evidence that actin assembly on purified phagosomes stimulates their fusion with late endocytic compartments in vitro. In this study, we further investigated the role of ezrin in phagosome maturation. We engineered a structurally open form of ezrin and demonstrated that ezrin binds directly to the actin assembly promoting factor N-WASP (Neural Wiskott-Aldrich Syndrome Protein) by its FERM domain. Using a cell-free system, we found that ezrin stimulates F-actin assembly on purified phagosomes by recruiting the N-WASP-Arp2/3 machinery. Accordingly, we showed that the down-regulation of ezrin activity in macrophages by a dominant-negative approach caused reduced F-actin accumulation on maturing phagosomes. Furthermore, using fluorescence and electron microscopy, we found that ezrin is required for the efficient fusion between phagosomes and lysosomes. Live-cell imaging analysis supported the notion that ezrin is necessary for the fusogenic process itself, promoting the transfer of the lysosome content into the phagosomal lumen.
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Affiliation(s)
- Sabrina Marion
- Department of Cell Biology and Biophysics, European Molecular Biology Laboratory, Heidelberg, Germany.
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33
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Matschulat A, Drescher D, Kneipp J. Surface-enhanced Raman scattering hybrid nanoprobe multiplexing and imaging in biological systems. ACS NANO 2010; 4:3259-69. [PMID: 20503969 DOI: 10.1021/nn100280z] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Surface-enhanced Raman scattering (SERS) labels and probes consisting of gold and silver nanoaggregates and attached reporter molecules can be identified by the Raman signature of the reporter molecule. At the same time, SERS hybrid probes deliver sensitive molecular structural information on their nanoenvironment. Here we demonstrate full exploitation of the multifunctional and multiplexing capabilities inherent to such nanoprobes by applying cluster methods and principal components approaches for discrimination beyond the visual inspection of individual spectra that has been practiced so far. The reported results indicate that fast, multivariate evaluation of whole sets of multiple probes is feasible. Spectra of five different reporters were shown to be separable by hierarchical clustering and by principal components analysis (PCA). In a duplex imaging approach in live cells, hierarchical cluster analysis, K-means clustering, and PCA were used for imaging the positions of different types of SERS probes along with the spectral information from cellular constituents. Parallel to cellular imaging experiments, cytotoxicity of the SERS hybrid probes containing aromatic thiols as reporters is assessed. The reported results suggest multiplexing applications of the nontoxic SERS nanoprobes in high density sensing and imaging in complex biological structures.
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Affiliation(s)
- Andrea Matschulat
- Federal Institute for Materials Research and Testing, Richard-Willstatter-Strasse 11, 12489 Berlin, Germany
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Rajagopalan S, Moyle MW, Joosten I, Long EO. DNA-PKcs controls an endosomal signaling pathway for a proinflammatory response by natural killer cells. Sci Signal 2010; 3:ra14. [PMID: 20179272 DOI: 10.1126/scisignal.2000467] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Endosomes are emerging as specialized signaling compartments that endow receptors with distinct signaling properties. The diversity of endosomal signaling pathways and their contribution to various biological responses is still unclear. CD158d, which is also known as the killer cell immunoglobulin-like receptor (KIR) 2DL4 (KIR2DL4), is an endosome-resident receptor in natural killer (NK) cells that stimulates the release of a unique set of proinflammatory and proangiogenic mediators in response to soluble human leukocyte antigen G (HLA-G). Here, we identified the CD158d signaling cascade. In response to soluble agonist antibody or soluble HLA-G, signaling by CD158d was dependent on the activation of nuclear factor kappaB (NF-kappaB) and the serine-threonine kinase Akt. CD158d associated with the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), promoted the recruitment of Akt to endosomes, and stimulated the DNA-PKcs-dependent phosphorylation of Akt. The sequential requirement for DNA-PKcs, Akt, and NF-kappaB in signaling by CD158d delineates a previously uncharacterized endosomal signaling pathway for a proinflammatory response in NK cells.
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Affiliation(s)
- Sumati Rajagopalan
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA.
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Stokes RW, Waddell SJ. Adjusting to a new home: Mycobacterium tuberculosis gene expression in response to an intracellular lifestyle. Future Microbiol 2010; 4:1317-35. [PMID: 19995191 DOI: 10.2217/fmb.09.94] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Mycobacterium tuberculosis remains the most significant single species of bacteria causing disease in mankind. The ability of M. tuberculosis to survive and replicate within host macrophages is a pivotal step in its pathogenesis. Understanding the microenvironments that M. tuberculosis encounters within the macrophage and the adaptations that the bacterium undergoes to facilitate its survival will lead to insights into possible therapeutic targets for improved treatment of tuberculosis. This is urgently needed with the emergence of multi- and extensively drug resistant strains of M. tuberculosis. Significant advances have been made in understanding the macrophage response on encountering M. tuberculosis. Complementary information is also accumulating regarding the counter responses of M. tuberculosis during the various stages of its interactions with the host. As such, a picture is emerging delineating the gene expression of intracellular M. tuberculosis at different stages of the interaction with macrophages.
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Affiliation(s)
- Richard W Stokes
- Department of Paediatrics, University of British Columbia, British Columbia, Canada.
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Yao W, Li K, Liao K. Macropinocytosis contributes to the macrophage foam cell formation in RAW264.7 cells. Acta Biochim Biophys Sin (Shanghai) 2009; 41:773-80. [PMID: 19727526 DOI: 10.1093/abbs/gmp066] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The key event in the atherosclerosis development is the lipids uptake by macrophage and the formation of foam cell in subendothelial arterial space. Besides the uptake of modified low-density lipoprotein (LDL) by scavenger receptor-mediated endocytosis, macrophages possess constitutive macropinocytosis, which is capable of taking up a large quantity of solute. Macrophage foam cell formation could be induced in RAW264.7 cells by increasing the serum concentration in the culture medium. Foam cell formation induced by serum could be blocked by phosphoinositide 3-kinase inhibitor, LY294002 or wortmannin, which inhibited macropinocytosis but not receptor-mediated endocytosis. Further analysis indicated that macropinocytosis took place at the gangliosides-enriched membrane area. Cholesterol depletion by beta-methylcyclodextrin-blocked macropinocytosis without affecting scavenger receptor-mediated endocytosis of modified LDLs. These results suggested that macropinocytosis might be one of the important mechanisms for lipid uptake in macrophage. And it made significant contribution to the lipid accumulation and foam cell formation.
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Affiliation(s)
- Wenqi Yao
- Department of Hematology, Xiangya Hospital, Central South University, Changsha 410008, China
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de Chastellier C, Forquet F, Gordon A, Thilo L. Mycobacterium requires an all-around closely apposing phagosome membrane to maintain the maturation block and this apposition is re-established when it rescues itself from phagolysosomes. Cell Microbiol 2009; 11:1190-207. [DOI: 10.1111/j.1462-5822.2009.01324.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Hsiao YC, Tong ZJ, Westfall JE, Ault JG, Page-McCaw PS, Ferland RJ. Ahi1, whose human ortholog is mutated in Joubert syndrome, is required for Rab8a localization, ciliogenesis and vesicle trafficking. Hum Mol Genet 2009; 18:3926-41. [PMID: 19625297 DOI: 10.1093/hmg/ddp335] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The primary non-motile cilium, a membrane-ensheathed, microtubule-bundled organelle, extends from virtually all cells and is important for development. Normal functioning of the cilium requires proper axoneme assembly, membrane biogenesis and ciliary protein localization, in tight coordination with the intraflagellar transport system and vesicular trafficking. Disruptions at any level can induce severe alterations in cell function, giving rise to a myriad of human genetic diseases known as ciliopathies. Here we show that the Abelson helper integration site 1 (Ahi1) gene, whose human ortholog is mutated in Joubert syndrome, regulates cilium formation via its interaction with Rab8a, a small GTPase critical for polarized membrane trafficking. We find that the Ahi1 protein localizes to a single centriole, the mother centriole, which becomes the basal body of the primary cilium. In order to determine whether Ahi1 functions in ciliogenesis, loss of function analysis of Ahi1 was performed in cell culture models of ciliogenesis. Knockdown of Ahi1 expression by shRNAi in cells or targeted deletion of Ahi1 (Ahi1 knockout mouse) leads to impairments in ciliogenesis. In Ahi1-knockdown cells, Rab8a is destabilized and does not properly localize to the basal body. Since Rab8a is implicated in vesicular trafficking, we next examined this process in Ahi1-knockdown cells. Defects in the trafficking of endocytic vesicles from the plasma membrane to the Golgi and back to the plasma membrane were observed in Ahi1-knockdown cells. Overall, our data indicate that the distribution and functioning of Rab8a is regulated by Ahi1, not only affecting cilium formation, but also vesicle transport.
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Affiliation(s)
- Yi-Chun Hsiao
- Department of Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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Pryor PR, Luzio JP. Delivery of endocytosed membrane proteins to the lysosome. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:615-24. [DOI: 10.1016/j.bbamcr.2008.12.022] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 12/01/2008] [Accepted: 12/12/2008] [Indexed: 01/21/2023]
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40
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Gan Z, Ram S, Vaccaro C, Ober RJ, Ward ES. Analyses of the recycling receptor, FcRn, in live cells reveal novel pathways for lysosomal delivery. Traffic 2009; 10:600-14. [PMID: 19192244 DOI: 10.1111/j.1600-0854.2009.00887.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Lysosomes play a central role in the degradation of proteins and other macromolecules. The mechanisms by which receptors are transferred to lysosomes for constitutive degradation are poorly understood. We have analyzed the processes that lead to the lysosomal delivery of the Fc receptor, FcRn. These studies provide support for a novel pathway for receptor delivery. Specifically, unlike other receptors that enter intraluminal vesicles in late endosomes, FcRn is transferred from the limiting membrane of such endosomes to lysosomes, and is rapidly internalized into the lysosomal lumen. By contrast, LAMP-1 persists on the limiting membrane. Receptor transfer is mediated by tubular extensions from late endosomes to lysosomes, or by interactions of the two participating organelles in kiss-and-linger-like processes, whereas full fusion is rarely observed. The persistence of FcRn on the late endosomal limiting membrane, together with selective transfer to lysosomes, allows this receptor to undergo recycling or degradation. Consequently, late endosomes have functional plasticity, consistent with the presence of the Rab5 GTPase in discrete domains on these compartments.
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Affiliation(s)
- Zhuo Gan
- Biomedical Engineering Graduate Program, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
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41
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ARF6, PI3-kinase and host cell actin cytoskeleton in Toxoplasma gondii cell invasion. Biochem Biophys Res Commun 2008; 378:656-61. [PMID: 19061866 DOI: 10.1016/j.bbrc.2008.11.108] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Accepted: 11/21/2008] [Indexed: 11/21/2022]
Abstract
Toxoplasma gondii infects a variety of different cell types in a range of different hosts. Host cell invasion by T. gondii occurs by active penetration of the host cell, a process previously described as independent of host actin polymerization. Also, the parasitophorous vacuole has been shown to resist fusion with endocytic and exocytic pathways of the host cell. ADP-ribosylation factor-6 (ARF6) belongs to the ARF family of small GTP-binding proteins. ARF6 regulates membrane trafficking and actin cytoskeleton rearrangements at the plasma membrane. Here, we have observed that ARF6 is recruited to the parasitophorous vacuole of tachyzoites of T. gondii RH strain and it also plays an important role in the parasite cell invasion with activation of PI3-kinase and recruitment of PIP(2) and PIP(3) to the parasitophorous vacuole of invading parasites. Moreover, it was verified that maintenance of host cell actin cytoskeleton integrity is important to parasite invasion.
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Gueirard P, Laplante A, Rondeau C, Milon G, Desjardins M. Trafficking of Leishmania donovani promastigotes in non-lytic compartments in neutrophils enables the subsequent transfer of parasites to macrophages. Cell Microbiol 2007; 10:100-11. [PMID: 17651446 DOI: 10.1111/j.1462-5822.2007.01018.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inoculation of Leishmania (L.) spp. promastigotes in the dermis of mammals by blood-feeding sand flies can be accompanied by the rapid recruitment of neutrophils, inflammatory monocytes and dendritic cells. Despite the presence of these lytic leucocytes, parasitism is efficiently established. We show here that Leishmania donovani promastigotes are targeted to two different compartments in neutrophils. The compartments harbouring either damaged or non-damaged parasites were characterized at the electron microscopy (EM) level using the glucose 6-phosphatase cytochemistry and endosome-phagosome fusion assays. One involves the contribution of lysosomes leading to the formation of highly lytic compartments where parasites are rapidly degraded. The other is lysosome-independent and involves the contribution of a compartment displaying some features of the endoplasmic reticulum (ER) where parasites are protected from degradation. Using genetically modified parasites, we show that the promastigote surface lipophosphoglycan (LPG) is required to inhibit lysosome fusion and maintain parasites in neutrophil compartments displaying ER features. L. donovani-harbouring neutrophils that eventually enter apoptosis can be phagocytosed by macrophages enabling the stealth entry of parasites into their final replicative host cells. Thus, the ability of L. donovani to avoid trafficking into lysosomes-derived compartments in short-lived neutrophils constitutes a key process for the subsequent establishment of long-term parasitism.
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Affiliation(s)
- Pascale Gueirard
- Département de Pathologie et Biologie Cellulaire, Université de Montréal, C.P.6128, Succ. Centre ville, Montreal, Canada.
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Howell GJ, Holloway ZG, Cobbold C, Monaco AP, Ponnambalam S. Cell biology of membrane trafficking in human disease. ACTA ACUST UNITED AC 2007; 252:1-69. [PMID: 16984815 PMCID: PMC7112332 DOI: 10.1016/s0074-7696(06)52005-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Understanding the molecular and cellular mechanisms underlying membrane traffic pathways is crucial to the treatment and cure of human disease. Various human diseases caused by changes in cellular homeostasis arise through a single gene mutation(s) resulting in compromised membrane trafficking. Many pathogenic agents such as viruses, bacteria, or parasites have evolved mechanisms to subvert the host cell response to infection, or have hijacked cellular mechanisms to proliferate and ensure pathogen survival. Understanding the consequence of genetic mutations or pathogenic infection on membrane traffic has also enabled greater understanding of the interactions between organisms and the surrounding environment. This review focuses on human genetic defects and molecular mechanisms that underlie eukaryote exocytosis and endocytosis and current and future prospects for alleviation of a variety of human diseases.
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Affiliation(s)
- Gareth J Howell
- Endothelial Cell Biology Unit, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
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44
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Yates RM, Hermetter A, Taylor GA, Russell DG. Macrophage Activation Downregulates the Degradative Capacity of the Phagosome. Traffic 2006; 8:241-50. [PMID: 17319801 DOI: 10.1111/j.1600-0854.2006.00528.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The phagosome is key to most macrophage functions. It is the site of degradation of particulate material, of bacterial killing and the generation of peptides for antigen presentation. Despite its role at the fulcrum of the innate and acquired immune systems, little is known about the physiology of this organelle in activated macrophages. In this study, we utilize fluorometric techniques to characterize functional alterations in the lumenal environment of the maturing phagosome following stimulation of macrophages with interferon-gamma and/or lipopolysaccharide. In addition to modulating the kinetics of phagosomal acidification, activation results in a phagosome with diminished hydrolytic activities that varies markedly with the activation status of the cell. Differential levels of proteolytic, lipolytic and beta-galactosidase activities were observed in the phagosome but not in the total lysosomal extract, indicating selective delivery of enzymes to the developing phagosome. Despite the suppression of hydrolytic activities observed in early phagosomes, late phagosomes exhibit an enhanced and protracted accumulation of lysosomal cargo. The data are consistent with limiting proteolysis in the early phagosome to maximize epitope generation and antigen presentation while sequestering the degradative capacity in the late phagolysosome.
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Affiliation(s)
- Robin M Yates
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14863, USA
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45
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Sedej S, Rupnik M, Zorec R. Endocytosis-dominated membrane area decrease requires Rab5 protein in rat melanotrophs. Ann N Y Acad Sci 2006; 1048:272-80. [PMID: 16154939 DOI: 10.1196/annals.1342.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Eukaryotic cells internalize extracellular macromolecules by endocytosis and it was shown that Rab5 protein is required for this process. While it is clear that endocytosis consists of vesicle fission from the plasma membrane, the role of Rab5 protein in the plasma membrane surface area changes is still unclear. Here we studied whether Rab5 is required for membrane surface area changes in rat melanotrophs-cells deriving from the pituitary pars intermedia. The presence of this protein in melanotrophs was probed by immunocytochemistry and its putative role in membrane area dynamics was monitored electrophysiologically with membrane capacitance measurements as this parameter directly reflects changes in membrane surface area. We found that Rab5 protein exists in melanotrophs. At [Ca(2+)](i) < 3 microM, endocytosis-dominated membrane capacitance decrease was found to be blocked by microinjection of specific Rab5 antibody. At high [Ca(2+)](i), Rab5 antibody did not affect the steady-state increase in membrane capacitance, while it elevated the rate of membrane capacitance increase, which is consistent with an inhibition of endocytosis.
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Affiliation(s)
- Simon Sedej
- Laboratory of Neuroendocrinology-Molecular Cell Physiology, Institute of Pathophysiology, Medical Faculty, University of Ljubljana, Slovenia
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46
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Bringer MA, Glasser AL, Tung CH, Méresse S, Darfeuille-Michaud A. The Crohn's disease-associated adherent-invasive Escherichia coli strain LF82 replicates in mature phagolysosomes within J774 macrophages. Cell Microbiol 2006; 8:471-84. [PMID: 16469058 DOI: 10.1111/j.1462-5822.2005.00639.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Adherent-invasive Escherichia coli (AIEC) bacteria isolated from Crohn's disease patients are able to extensively replicate within macrophages in large vacuoles. The mechanism by which AIEC bacteria survive within phagocytic cells is unknown. This report describes the maturation of AIEC LF82-containing phagosomes within J774 macrophages. LF82-containing phagosomes traffic through the endocytic pathway as shown by the sequential acquisition and loss of EEA1 and Rab7 and by accumulation of Lamp-1, Lamp-2 and cathepsin D. We demonstrated that AIEC LF82-containing phagosomes mature into active phagolysosomes where bacteria are exposed to low pH and to the degradative activity of cathepsin D. Finally, we showed that an acidic environment is necessary for replication of AIEC LF82 bacteria within J774 macrophages. Thus, evidence is provided that AIEC LF82 bacteria do not escape from the endocytic pathway but undergo normal interaction with host endomembrane organelles and replicate within acidic and cathepsin D-positive vacuolar phagolysosomes.
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Affiliation(s)
- Marie-Agnès Bringer
- Pathogénie Bactérienne Intestinale, Laboratoire de Bactériologie, USC INRA 2018, Université d'Auvergne, CBRV, Clermont-Ferrand, France
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47
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Nepal RM, Mampe S, Shaffer B, Erickson AH, Bryant P. Cathepsin L maturation and activity is impaired in macrophages harboring M. avium and M. tuberculosis. Int Immunol 2006; 18:931-9. [PMID: 16636015 DOI: 10.1093/intimm/dxl029] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mycobacterium tuberculosis-infected macrophages demonstrate diminished capacity to present antigens via class II MHC molecules. Since successful class II MHC-restricted antigen presentation relies on the actions of endocytic proteases, we asked whether the activities of cathepsins (Cat) B, S and L-three major lysosomal cysteine proteases-are modulated in macrophages infected with pathogenic Mycobacterium spp. Infection of murine bone marrow-derived macrophages with either Mycobacterium avium or M. tuberculosis had no obvious effect on Cat B or Cat S activity. In contrast, the activity of Cat L was altered in infected cells. Specifically, whereas the 24-kDa two-chain mature form of active Cat L predominated in uninfected cells, we observed an increase in the steady-state activity of the precursor single-chain (30 kDa) and 25-kDa two-chain forms of the enzyme in cells infected with either M. avium or M. tuberculosis. Pulse-chase analyses revealed that maturation of nascent, single-chain Cat L into the 25-kDa two-chain form was impaired in infected macrophages, and that maturation into the 24-kDa two-chain form did not occur. Consistent with these data, M. avium infection inhibited the IFNgamma-induced secretion of active two-chain Cat L by macrophages. Viable bacilli were not required to disrupt Cat L maturation, suggesting that a constitutively expressed mycobacterial component was responsible. The absence of the major active form of lysosomal Cat L in M. avium- and M. tuberculosis-infected macrophages may influence the types of T cell epitopes generated in these antigen-presenting cells, and/or the rate of class II MHC peptide loading.
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Affiliation(s)
- Rajeev M Nepal
- Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA
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48
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Hsu T, Adereth Y, Kose N, Dammai V. Endocytic function of von Hippel-Lindau tumor suppressor protein regulates surface localization of fibroblast growth factor receptor 1 and cell motility. J Biol Chem 2006; 281:12069-80. [PMID: 16505488 PMCID: PMC2367321 DOI: 10.1074/jbc.m511621200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The tumor suppressor VHL (von Hippel-Lindau protein) serves as a negative regulator of hypoxia-inducible factor-alpha subunits. However, accumulated evidence indicates that VHL may play additional roles in other cellular functions. We report here a novel hypoxia-inducible factor-independent function of VHL in cell motility control via regulation of fibroblast growth factor receptor 1 (FGFR1) endocytosis. In VHL null tumor cells or VHL knock-down cells, FGFR1 internalization is defective, leading to surface accumulation and abnormal activation of FGFR1. The enhanced FGFR1 activity directly correlates with increased cell migration. VHL disease mutants, in two of the mutation hot spots favoring development of renal cell carcinoma, failed to rescue the above phenotype. Interestingly, surface accumulation of the chemotactic receptor appears to be selective in VHL mutant cells, since other surface proteins such as epidermal growth factor receptor, platelet-derived growth factor receptor, IGFR1, and c-Met are not affected. We demonstrate that 1) FGFR1 endocytosis is defective in the VHL mutant and is rescued by reexpression of wild-type VHL, 2) VHL is recruited to FGFR1-containing, but not EGFR-containing, endosomal vesicles, 3) VHL exhibits a functional relationship with Rab5a and dynamin 2 in FGFR1 internalization, and 4) the endocytic function of VHL is mediated through the metastasis suppressor Nm23, a protein known to regulate dynamin-dependent endocytosis.
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Affiliation(s)
- Tien Hsu
- To whom correspondence may be addressed: Dept. of Pathology and Laboratory Medicine and Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas St., HCC330, Charleston, SC 29425. Tel.: 843-792-0638; Fax: 843-792-5002; E-mail:
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49
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Kiss RS, Ma Z, Nakada-Tsukui K, Brugnera E, Vassiliou G, McBride HM, Ravichandran KS, Marcel YL. The lipoprotein receptor-related protein-1 (LRP) adapter protein GULP mediates trafficking of the LRP ligand prosaposin, leading to sphingolipid and free cholesterol accumulation in late endosomes and impaired efflux. J Biol Chem 2006; 281:12081-92. [PMID: 16497666 DOI: 10.1074/jbc.m600621200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
One of the conserved functional pathways linked to engulfment of apoptotic corpses involves two membrane proteins low density lipoprotein receptor-related protein-1 (LRP) and ABCA1 and the LRP adapter protein GULP. Because LRP and ABCA1 play roles in cellular lipid trafficking and efflux, here we addressed whether the third member, the LRP adapter protein GULP, also affects cellular lipid transport. Several lines of evidence show that overexpression of GULP causes glycosphingolipid and free cholesterol accumulation in the late endosome/lysosome compartment that is accompanied by down-regulation of ABCA1 and decreased efflux. Conversely, knockdown of endogenous GULP expression promoted cholesterol flux through the late endosomes and up-regulation of ABCA1, even in the context of a disease state such as Niemann-Pick Type C disease. Mechanistically, we were able to show that trafficking of the LRP ligands alpha2-macroglobulin and prosaposin, a protein cofactor necessary for glycosphingolipid degradation, are impaired in cells expressing full-length GULP protein, resulting in glycosphingolipid and free cholesterol accumulation in the late endosome/lysosome compartment. On the other hand, knockdown of endogenous GULP results in enhanced targeting of prosaposin and enhanced clearance of glycosphingolipids and cholesterol from the late endosomes. Taken together, these data reveal that GULP/LRP/ABCA1 represents a triad of molecules involved in engulfment and cellular lipid homeostasis.
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Affiliation(s)
- Robert S Kiss
- Lipoprotein and Atherosclerosis Research Group, Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa K1Y 4W7, Canada
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50
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Vidricaire G, Tremblay MJ. Rab5 and Rab7, but Not ARF6, Govern the Early Events of HIV-1 Infection in Polarized Human Placental Cells. THE JOURNAL OF IMMUNOLOGY 2005; 175:6517-30. [PMID: 16272306 DOI: 10.4049/jimmunol.175.10.6517] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Trophoblasts, the structural cells of the placenta, are thought to play a determinant role in in utero HIV type 1 (HIV-1) transmission. We have accumulated evidence suggesting that HIV-1 infection of these cells is associated with uptake by an unusual clathrin/caveolae-independent endocytic pathway and that endocytosis is followed by trafficking through multiple organelles. Furthermore, part of this trafficking involves the transit of HIV-1 from transferrin-negative to EEA1 and transferrin-positive endosomes, suggesting a merger from nonclassical to classical endocytic pathways in these cells. In the present article, the relationship between the presence of HIV-1 within specific endosomes and infection was studied. We demonstrate that viral infection is virtually lost when endosome inhibitors are added shortly after exposure to HIV-1. Thus, contrary to what is seen in CD4+ T lymphocytes, the initial presence of HIV-1 within the endosomes is mandatory for infection to take place. Importantly, this process is independent of the viral envelope proteins gp120 and gp41. The Rab family of small GTPases coordinates the vesicular transport between the different endocytic organelles. Experiments performed with various expression vectors indicated that HIV-1 infection in polarized trophoblasts relies on Rab5 and Rab7 without the contribution of Arf6 or Rab11. Furthermore, we conclude that Rab5 drives movements from raft-rich region to early endosomes, and this transit is required for subsequently reaching late endosomes via Rab7. This complex trafficking is mandatory for HIV-1 infection to proceed in human polarized trophoblasts.
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Affiliation(s)
- Gaël Vidricaire
- Research Center in Infectious Diseases, Centre Hospitalier de l'Université Laval Research Center, and Faculty of Medicine, Laval University, Quebec City, Quebec, Canada
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