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Eriksson I, Öllinger K. Lysosomes in Cancer-At the Crossroad of Good and Evil. Cells 2024; 13:459. [PMID: 38474423 DOI: 10.3390/cells13050459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/27/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024] Open
Abstract
Although it has been known for decades that lysosomes are central for degradation and recycling in the cell, their pivotal role as nutrient sensing signaling hubs has recently become of central interest. Since lysosomes are highly dynamic and in constant change regarding content and intracellular position, fusion/fission events allow communication between organelles in the cell, as well as cell-to-cell communication via exocytosis of lysosomal content and release of extracellular vesicles. Lysosomes also mediate different forms of regulated cell death by permeabilization of the lysosomal membrane and release of their content to the cytosol. In cancer cells, lysosomal biogenesis and autophagy are increased to support the increased metabolism and allow growth even under nutrient- and oxygen-poor conditions. Tumor cells also induce exocytosis of lysosomal content to the extracellular space to promote invasion and metastasis. However, due to the enhanced lysosomal function, cancer cells are often more susceptible to lysosomal membrane permeabilization, providing an alternative strategy to induce cell death. This review summarizes the current knowledge of cancer-associated alterations in lysosomal structure and function and illustrates how lysosomal exocytosis and release of extracellular vesicles affect disease progression. We focus on functional differences depending on lysosomal localization and the regulation of intracellular transport, and lastly provide insight how new therapeutic strategies can exploit the power of the lysosome and improve cancer treatment.
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Affiliation(s)
- Ida Eriksson
- Division of Cell Biology, Department of Biomedical and Clinical Sciences, Linköping University, 58185 Linköping, Sweden
| | - Karin Öllinger
- Division of Cell Biology, Department of Biomedical and Clinical Sciences, Linköping University, 58185 Linköping, Sweden
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2
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Navratna V, Kumar A, Mosalaganti S. Structure of the human heparan-α-glucosaminide N-acetyltransferase (HGSNAT). BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.23.563672. [PMID: 37961489 PMCID: PMC10634761 DOI: 10.1101/2023.10.23.563672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Degradation of heparan sulfate (HS), a glycosaminoglycan (GAG) comprised of repeating units of N-acetylglucosamine and glucuronic acid, begins in the cytosol and is completed in the lysosomes. Acetylation of the terminal non-reducing amino group of α-D-glucosamine of HS is essential for its complete breakdown into monosaccharides and free sulfate. Heparan-α-glucosaminide N-acetyltransferase (HGSNAT), a resident of the lysosomal membrane, catalyzes this essential acetylation reaction by accepting and transferring the acetyl group from cytosolic acetyl-CoA to terminal α-D-glucosamine of HS in the lysosomal lumen. Mutation-induced dysfunction in HGSNAT causes abnormal accumulation of HS within the lysosomes and leads to an autosomal recessive neurodegenerative lysosomal storage disorder called mucopolysaccharidosis IIIC (MPS IIIC). There are no approved drugs or treatment strategies to cure or manage the symptoms of, MPS IIIC. Here, we use cryo-electron microscopy (cryo-EM) to determine a high-resolution structure of the HGSNAT-acetyl-CoA complex in an open-to-lumen conformation, the first step in HGSNAT catalyzed acetyltransferase reaction. In addition, we map the known MPS IIIC mutations onto the structure and elucidate the molecular basis for mutation-induced HGSNAT dysfunction.
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Affiliation(s)
- Vikas Navratna
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109, United States
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Arvind Kumar
- Thermo Fisher Scientific, Waltham, Massachusetts, 02451, United States
| | - Shyamal Mosalaganti
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109, United States
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, 48109, United States
- Department of Biophysics, College of Literature, Science and the Arts, University of Michigan, Ann Arbor, Michigan, 48109, United States
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3
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Mentrup T, Stumpff-Niggemann AY, Leinung N, Schlosser C, Schubert K, Wehner R, Tunger A, Schatz V, Neubert P, Gradtke AC, Wolf J, Rose-John S, Saftig P, Dalpke A, Jantsch J, Schmitz M, Fluhrer R, Jacobsen ID, Schröder B. Phagosomal signalling of the C-type lectin receptor Dectin-1 is terminated by intramembrane proteolysis. Nat Commun 2022; 13:1880. [PMID: 35388002 PMCID: PMC8987071 DOI: 10.1038/s41467-022-29474-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/14/2022] [Indexed: 11/23/2022] Open
Abstract
Sensing of pathogens by pattern recognition receptors (PRR) is critical to initiate protective host defence reactions. However, activation of the immune system has to be carefully titrated to avoid tissue damage necessitating mechanisms to control and terminate PRR signalling. Dectin-1 is a PRR for fungal β-glucans on immune cells that is rapidly internalised after ligand-binding. Here, we demonstrate that pathogen recognition by the Dectin-1a isoform results in the formation of a stable receptor fragment devoid of the ligand binding domain. This fragment persists in phagosomal membranes and contributes to signal transduction which is terminated by the intramembrane proteases Signal Peptide Peptidase-like (SPPL) 2a and 2b. Consequently, immune cells lacking SPPL2b demonstrate increased anti-fungal ROS production, killing capacity and cytokine responses. The identified mechanism allows to uncouple the PRR signalling response from delivery of the pathogen to degradative compartments and identifies intramembrane proteases as part of a regulatory circuit to control anti-fungal immune responses. Dectin-1 is a critical component of the innate sensing repertoire which is involved in pattern based recognition of fungal pathogens. Here the authors show that intramembrane proteolysis is involved in the regulation of the antifungal host response by termination of the phagosomal signalling of Dectin-1.
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Affiliation(s)
- Torben Mentrup
- Institute of Physiological Chemistry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | | | - Nadja Leinung
- Institute of Physiological Chemistry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Christine Schlosser
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Augsburg, Germany
| | - Katja Schubert
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Rebekka Wehner
- Institute of Immunology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Antje Tunger
- Institute of Immunology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Dresden, Germany
| | - Valentin Schatz
- Institute of Clinical Microbiology and Hygiene, University Hospital of Regensburg and University of Regensburg, Regensburg, Germany
| | - Patrick Neubert
- Institute of Clinical Microbiology and Hygiene, University Hospital of Regensburg and University of Regensburg, Regensburg, Germany
| | - Ann-Christine Gradtke
- Institute of Physiological Chemistry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Janina Wolf
- Biochemical Institute, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Stefan Rose-John
- Biochemical Institute, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Paul Saftig
- Biochemical Institute, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Alexander Dalpke
- Institute of Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Medical Faculty, Technische Universität Dresden, Dresden, Germany
| | - Jonathan Jantsch
- Institute of Clinical Microbiology and Hygiene, University Hospital of Regensburg and University of Regensburg, Regensburg, Germany
| | - Marc Schmitz
- Institute of Immunology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Regina Fluhrer
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Augsburg, Germany
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Bernd Schröder
- Institute of Physiological Chemistry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
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4
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Sang H, Liu J, Zhou F, Zhang X, Zhang J, Liu Y, Wang G, Ye H. Target-responsive subcellular catabolism analysis for early-stage antibody-drug conjugates screening and assessment. Acta Pharm Sin B 2021; 11:4020-4031. [PMID: 35024323 PMCID: PMC8727762 DOI: 10.1016/j.apsb.2021.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/08/2021] [Accepted: 05/18/2021] [Indexed: 12/11/2022] Open
Abstract
Events including antibody‒antigen affinity, internalization, trafficking and lysosomal proteolysis combinatorially determine the efficiency of antibody-drug conjugate (ADC) catabolism and hence the toxicity. Nevertheless, an approach that conveniently identifies proteins requisite for payload release and the ensuing toxicity for mechanistic studies and quality assessment is lacking. Considering the plethora of ADC candidates under development, we developed a target-responsive subcellular catabolism (TARSC) approach that examines ADC catabolism and probes changes in response to targeted interferences of proteins of interest. We firstly applied TARSC to study the commercial T-DM1 and the biosimilar. We recorded unequivocal catabolic behaviors regardless of the absence and presence of the targeted interferences. Their negligible differences in TARSC profiles agreed with their undifferentiated anti-tumoral efficacy according to further in vitro viability and in vivo tumor growth assays, highlighting TARSC analysis as a useful tool for biosimilarity assessment and functional dissection of proteins requisite for ADC catabolism. Additionally, we employed TARSC to investigate the catabolic behavior of a new trastuzumab-toxin conjugate. Collectively, TARSC can not only characterize ADC catabolism at (sub)cellular level but also comprehensively determine which protein targets affect payload release and therapeutic outcomes. Future use of TARSC is thus anticipated in early-stage screening, quality assessment and mechanistic investigations of ADCs.
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Affiliation(s)
- Hua Sang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
- Department of Pharmacy, the Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Jiali Liu
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Fang Zhou
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Xiaofang Zhang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Jingwei Zhang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Yazhong Liu
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
| | - Guangji Wang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
- Corresponding authors. Tel.: +86 25 83271176 (Guangji Wang), +86 25 83271179 (Hui Ye)
| | - Hui Ye
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China
- Corresponding authors. Tel.: +86 25 83271176 (Guangji Wang), +86 25 83271179 (Hui Ye)
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5
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Autophagy lysosomal pathway dysfunction in Parkinson's disease; evidence from human genetics. Parkinsonism Relat Disord 2020; 73:60-71. [DOI: 10.1016/j.parkreldis.2019.11.015] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 11/08/2019] [Accepted: 11/12/2019] [Indexed: 02/06/2023]
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6
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Kühnle N, Dederer V, Lemberg MK. Intramembrane proteolysis at a glance: from signalling to protein degradation. J Cell Sci 2019; 132:132/16/jcs217745. [DOI: 10.1242/jcs.217745] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ABSTRACT
Over the last two decades, a group of unusual proteases, so-called intramembrane proteases, have become increasingly recognized for their unique ability to cleave peptide bonds within cellular membranes. They are found in all kingdoms of life and fulfil versatile functions ranging from protein maturation, to activation of signalling molecules, to protein degradation. In this Cell Science at a Glance article and the accompanying poster, we focus on intramembrane proteases in mammalian cells. By comparing intramembrane proteases in different cellular organelles, we set out to review their functions within the context of the roles of individual cellular compartments. Additionally, we exemplify their mode of action in relation to known substrates by distinguishing cleavage events that promote degradation of substrate from those that release active domains from the membrane bilayer.
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Affiliation(s)
- Nathalie Kühnle
- Centre for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Verena Dederer
- Centre for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Marius K. Lemberg
- Centre for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
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7
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Früholz S, Fäßler F, Kolukisaoglu Ü, Pimpl P. Nanobody-triggered lockdown of VSRs reveals ligand reloading in the Golgi. Nat Commun 2018; 9:643. [PMID: 29440677 PMCID: PMC5811495 DOI: 10.1038/s41467-018-02909-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 01/08/2018] [Indexed: 11/17/2022] Open
Abstract
Protein degradation in lytic compartments is crucial for eukaryotic cells. At the heart of this process, vacuolar sorting receptors (VSRs) bind soluble hydrolases in the secretory pathway and release them into the vacuolar route. Sorting efficiency is suggested to result from receptor recycling. However, how and to where plant VSRs recycle remains controversial. Here we present a nanobody-epitope interaction-based protein labeling and tracking approach to dissect their anterograde and retrograde transport routes in vivo. We simultaneously employ two different nanobody-epitope pairs: one for the location-specific post-translational fluorescence labeling of receptors and the other pair to trigger their compartment-specific lockdown via an endocytosed dual-epitope linker protein. We demonstrate VSR recycling from the TGN/EE, thereby identifying the cis-Golgi as the recycling target and show that recycled VSRs reload ligands. This is evidence that bidirectional VSR-mediated sorting of vacuolar proteins exists and occurs between the Golgi and the TGN/EE.
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Affiliation(s)
- Simone Früholz
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Florian Fäßler
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Üner Kolukisaoglu
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Peter Pimpl
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany.
- SUSTech-PKU Institute of Plant and Food Science (IPFS), Department of Biology, Southern University of Science and Technology (SUSTech), 1088 Xueyuan Rd, Shenzhen, 518055, China.
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8
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Früholz S, Fäßler F, Kolukisaoglu Ü, Pimpl P. Nanobody-triggered lockdown of VSRs reveals ligand reloading in the Golgi. Nat Commun 2018. [PMID: 29440677 DOI: 10.1038/s41467-018-02909-2906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023] Open
Abstract
Protein degradation in lytic compartments is crucial for eukaryotic cells. At the heart of this process, vacuolar sorting receptors (VSRs) bind soluble hydrolases in the secretory pathway and release them into the vacuolar route. Sorting efficiency is suggested to result from receptor recycling. However, how and to where plant VSRs recycle remains controversial. Here we present a nanobody-epitope interaction-based protein labeling and tracking approach to dissect their anterograde and retrograde transport routes in vivo. We simultaneously employ two different nanobody-epitope pairs: one for the location-specific post-translational fluorescence labeling of receptors and the other pair to trigger their compartment-specific lockdown via an endocytosed dual-epitope linker protein. We demonstrate VSR recycling from the TGN/EE, thereby identifying the cis-Golgi as the recycling target and show that recycled VSRs reload ligands. This is evidence that bidirectional VSR-mediated sorting of vacuolar proteins exists and occurs between the Golgi and the TGN/EE.
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Affiliation(s)
- Simone Früholz
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Florian Fäßler
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Üner Kolukisaoglu
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Peter Pimpl
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany.
- SUSTech-PKU Institute of Plant and Food Science (IPFS), Department of Biology, Southern University of Science and Technology (SUSTech), 1088 Xueyuan Rd, Shenzhen, 518055, China.
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9
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Endocytic Trafficking of the Notch Receptor. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1066:99-122. [DOI: 10.1007/978-3-319-89512-3_6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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10
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Regulated intramembrane proteolysis: emergent role in cell signalling pathways. Biochem Soc Trans 2017; 45:1185-1202. [PMID: 29079648 DOI: 10.1042/bst20170002] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 08/27/2017] [Accepted: 08/29/2017] [Indexed: 12/12/2022]
Abstract
Receptor signalling events including those initiated following activation of cytokine and growth factor receptors and the well-characterised death receptors (tumour necrosis factor receptor, type 1, FasR and TRAIL-R1/2) are initiated at the cell surface through the recruitment and formation of intracellular multiprotein signalling complexes that activate divergent signalling pathways. Over the past decade, research studies reveal that many of these receptor-initiated signalling events involve the sequential proteolysis of specific receptors by membrane-bound proteases and the γ-secretase protease complexes. Proteolysis enables the liberation of soluble receptor ectodomains and the generation of intracellular receptor cytoplasmic domain fragments. The combined and sequential enzymatic activity has been defined as regulated intramembrane proteolysis and is now a fundamental signal transduction process involved in the termination or propagation of receptor signalling events. In this review, we discuss emerging evidence for a role of the γ-secretase protease complexes and regulated intramembrane proteolysis in cell- and immune-signalling pathways.
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11
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Nixon RA. Amyloid precursor protein and endosomal-lysosomal dysfunction in Alzheimer's disease: inseparable partners in a multifactorial disease. FASEB J 2017; 31:2729-2743. [PMID: 28663518 DOI: 10.1096/fj.201700359] [Citation(s) in RCA: 202] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 12/15/2022]
Abstract
Abnormalities of the endosomal-lysosomal network (ELN) are a signature feature of Alzheimer's disease (AD). These include the earliest known cytopathology that is specific to AD and that affects endosomes and induces the progressive failure of lysosomes, each of which are directly linked by distinct mechanisms to neurodegeneration. The origins of ELN dysfunction and β-amyloidogenesis closely overlap, which reflects their common genetic basis, the established early involvement of endosomes and lysosomes in amyloid precursor protein (APP) processing and clearance, and the pathologic effect of certain APP metabolites on ELN functions. Genes that promote β-amyloidogenesis in AD (APP, PSEN1/2, and APOE4) have primary effects on ELN function. The importance of primary ELN dysfunction to pathogenesis is underscored by the mutations in more than 35 ELN-related genes that, thus far, are known to cause familial neurodegenerative diseases even though different pathogenic proteins may be involved. In this article, I discuss growing evidence that implicates AD gene-driven ELN disruptions as not only the antecedent pathobiology that underlies β-amyloidogenesis but also as the essential partner with APP and its metabolites that drive the development of AD, including tauopathy, synaptic dysfunction, and neurodegeneration. The striking amelioration of diverse deficits in animal AD models by remediating ELN dysfunction further supports a need to integrate APP and ELN relationships, including the role of amyloid-β, into a broader conceptual framework of how AD arises, progresses, and may be effectively therapeutically targeted.-Nixon, R. A. Amyloid precursor protein and endosomal-lysosomal dysfunction in Alzheimer's disease: inseparable partners in a multifactorial disease.
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Affiliation(s)
- Ralph A Nixon
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, New York, USA; .,Department of Psychiatry and Department of Cell Biology, New York University Langone Medical Center, New York, New York, USA
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12
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Signal peptide peptidase and SPP-like proteases - Possible therapeutic targets? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017. [PMID: 28624439 DOI: 10.1016/j.bbamcr.2017.06.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Signal peptide peptidase (SPP) and the four homologous SPP-like proteases SPPL2a, SPPL2b, SPPL2c and SPPL3 are GxGD-type intramembrane-cleaving proteases (I-CLIPs). In addition to divergent subcellular localisations, distinct differences in the mechanistic properties and substrate requirements of individual family members have been unravelled. SPP/SPPL proteases employ a catalytic mechanism related to that of the γ-secretase complex. Nevertheless, differential targeting of SPP/SPPL proteases and γ-secretase by inhibitors has been demonstrated. Furthermore, also within the SPP/SPPL family significant differences in the sensitivity to currently available inhibitory compounds have been reported. Though far from complete, our knowledge on pathophysiological functions of SPP/SPPL proteases, in particular based on studies in mice, has been significantly increased over the last years. Based on this, inhibition of distinct SPP/SPPL proteases has been proposed as a novel therapeutic concept e.g. for the treatment of autoimmunity and viral or protozoal infections, as we will discuss in this review. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John.
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13
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Verhelst SHL. Intramembrane proteases as drug targets. FEBS J 2017; 284:1489-1502. [PMID: 27889944 DOI: 10.1111/febs.13979] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/14/2016] [Accepted: 11/24/2016] [Indexed: 01/04/2023]
Abstract
Proteases are considered attractive drug targets. Various drugs targeting classical, soluble proteases have been approved for treatment of human disease. Intramembrane proteases (IMPs) are a more recently discovered group of proteolytic enzymes. They are embedded in lipid bilayers and their active sites are located in the plane of a membrane. All four mechanistic families of IMPs have been linked to disease, but currently, no drugs against IMPs have entered the market. In this review, I will outline the function of IMPs with a focus on the ones involved in human disease, which includes Alzheimer's disease, cancer, and infectious diseases by microorganisms. Inhibitors of IMPs are known for all mechanistic classes, but are not yet very potent or selective - aside from those targeting γ-secretase. I will here describe the different features of IMP inhibitors and discuss a list of issues that need attention in the near future in order to improve the drug development for IMPs.
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Affiliation(s)
- Steven H L Verhelst
- Department of Cellular and Molecular Medicine, KU Leuven - University of Leuven, Belgium.,AG Chemical Proteomics, Leibniz Institute for Analytical Sciences ISAS, Dortmund, Germany
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14
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Abstract
CD74 is a cell-surface receptor for the cytokine macrophage migration inhibitory factor. Macrophage migration inhibitory factor binding to CD74 induces its intramembrane cleavage and the release of its cytosolic intracellular domain (CD74-ICD), which regulates cell survival. In the present study, we characterized the transcriptional activity of CD74-ICD in chronic lymphocytic B cells. We show that following CD74 activation, CD74-ICD interacts with the transcription factors RUNX (Runt related transcription factor) and NF-κB and binds to proximal and distal regulatory sites enriched for genes involved in apoptosis, immune response, and cell migration. This process leads to regulation of expression of these genes. Our results suggest that identifying targets of CD74 will help in understanding of essential pathways regulating B-cell survival in health and disease.
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