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Hernández-Cáceres MP, Pinto-Nuñez D, Rivera P, Burgos P, Díaz-Castro F, Criollo A, Yañez MJ, Morselli E. Role of lipids in the control of autophagy and primary cilium signaling in neurons. Neural Regen Res 2024; 19:264-271. [PMID: 37488876 PMCID: PMC10503597 DOI: 10.4103/1673-5374.377414] [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: 12/27/2022] [Revised: 03/09/2023] [Accepted: 04/27/2023] [Indexed: 07/26/2023] Open
Abstract
The brain is, after the adipose tissue, the organ with the greatest amount of lipids and diversity in their composition in the human body. In neurons, lipids are involved in signaling pathways controlling autophagy, a lysosome-dependent catabolic process essential for the maintenance of neuronal homeostasis and the function of the primary cilium, a cellular antenna that acts as a communication hub that transfers extracellular signals into intracellular responses required for neurogenesis and brain development. A crosstalk between primary cilia and autophagy has been established; however, its role in the control of neuronal activity and homeostasis is barely known. In this review, we briefly discuss the current knowledge regarding the role of autophagy and the primary cilium in neurons. Then we review the recent literature about specific lipid subclasses in the regulation of autophagy, in the control of primary cilium structure and its dependent cellular signaling in physiological and pathological conditions, specifically focusing on neurons, an area of research that could have major implications in neurodevelopment, energy homeostasis, and neurodegeneration.
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Affiliation(s)
- María Paz Hernández-Cáceres
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
| | - Daniela Pinto-Nuñez
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
| | - Patricia Rivera
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
- Physiology Department, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paulina Burgos
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
| | - Francisco Díaz-Castro
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
- Physiology Department, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alfredo Criollo
- Instituto de Investigación en Ciencias Odontológicas (ICOD), Facultad de Odontología, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Autophagy Research Center, Santiago, Chile
| | - Maria Jose Yañez
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
| | - Eugenia Morselli
- Department of Basic Sciences, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile
- Autophagy Research Center, Santiago, Chile
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2
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Kyun ML, Park T, Jung H, Kim I, Kwon JI, Jeong SY, Choi M, Park D, Lee YB, Moon KS. Development of an In Vitro Model for Inflammation Mediated Renal Toxicity Using 3D Renal Tubules and Co-Cultured Human Immune Cells. Tissue Eng Regen Med 2023; 20:1173-1190. [PMID: 37843784 PMCID: PMC10645777 DOI: 10.1007/s13770-023-00602-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 09/19/2023] [Accepted: 09/24/2023] [Indexed: 10/17/2023] Open
Abstract
BACKGROUND The emergence of various infectious diseases and the toxic effects of hyperinflammation by biotherapeutics have highlighted the need for in vitro preclinical models mimicking the human immune system. In vitro models studying the relationship between hyperinflammation and acute renal injury mainly rely on 2D culture systems, which have shown limitations in recapitulating kidney function. Herein, we developed an in vitro kidney toxicity model by co-culturing 3D engineered kidney proximal tubules cells (RPTEC/TERT1) with human peripheral blood mononuclear cells (PBMC). METHODS RPTEC/TERT1 were sandwich cultured to form 3D renal tubules for 16 days. The tubules were then co-cultured with PBMC using transwell (0.4 μm pores) for 24 h. Hyperinflammation of PBMC was induced during co-culture using polyinosinic-polycytidylic acid (polyI:C) and lipopolysaccharide (LPS) to investigate the effects of the induced hyperinflammation on the renal tubules. RESULTS Encapsulated RPTEC/TERT1 cells in Matrigel exhibited elevated renal function markers compared to 2D culture. The coexistence of PBMC and polyI:C induced a strong inflammatory response in the kidney cells. This hyperinflammation significantly reduced primary cilia formation and upregulated kidney injury markers along the 3D tubules. Similarly, treating co-cultured PBMC with LPS to induce hyperinflammation resulted in comparable inflammatory responses and potential kidney injury. CONCLUSION The model demonstrated similar changes in kidney injury markers following polyI:C and LPS treatment, indicating its suitability for detecting immune-associated kidney damage resulting from infections and biopharmaceutical applications.
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Affiliation(s)
- Mi-Lang Kyun
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Tamina Park
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Hyewon Jung
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Inhye Kim
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Ji-In Kwon
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Seo Yule Jeong
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Myeongjin Choi
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Daeui Park
- Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea
| | - Yu Bin Lee
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea.
| | - Kyoung-Sik Moon
- Department of Advanced Toxicology Research, Korea Institute of Toxicology, Daejeon, 34114, Republic of Korea.
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3
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Jang J, Yeo S, Baek S, Jung HJ, Lee MS, Choi SH, Choe Y. Abnormal accumulation of extracellular vesicles in hippocampal dystrophic axons and regulation by the primary cilia in Alzheimer's disease. Acta Neuropathol Commun 2023; 11:142. [PMID: 37667395 PMCID: PMC10478284 DOI: 10.1186/s40478-023-01637-3] [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: 06/21/2023] [Accepted: 08/15/2023] [Indexed: 09/06/2023] Open
Abstract
Dystrophic neurites (DNs) are abnormal axons and dendrites that are swollen or deformed in various neuropathological conditions. In Alzheimer's disease (AD), DNs play a crucial role in impairing neuronal communication and function, and they may also contribute to the accumulation and spread of amyloid beta (Aβ) in the brain of AD patients. However, it is still a challenge to understand the DNs of specific neurons that are vulnerable to Aβ in the pathogenesis of AD. To shed light on the development of radiating DNs, we examined enriched dystrophic hippocampal axons in a mouse model of AD using a three-dimensional rendering of projecting neurons. We employed the anterograde spread of adeno-associated virus (AAV)1 and conducted proteomic analysis of synaptic compartments obtained from hippocampo-septal regions. Our findings revealed that DNs were formed due to synaptic loss at the axon terminals caused by the accumulation of extracellular vesicle (EV). Abnormal EV-mediated transport and exocytosis were identified in association with primary cilia, indicating their involvement in the accumulation of EVs at presynaptic terminals. To further address the regulation of DNs by primary cilia, we conducted knockdown of the Ift88 gene in hippocampal neurons, which impaired EV-mediated secretion of Aβ and promoted accumulation of axonal spheroids. Using single-cell RNA sequencing, we identified the septal projecting hippocampal somatostatin neurons (SOM) as selectively vulnerable to Aβ with primary cilia dysfunction and vesicle accumulation. Our study suggests that DNs in AD are initiated by the ectopic accumulation of EVs at the neuronal axon terminals, which is affected by neuronal primary cilia.
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Affiliation(s)
| | - Seungeun Yeo
- Korea Brain Research Institute, Daegu, 41068, Korea
| | | | | | - Mi Suk Lee
- Korea Brain Research Institute, Daegu, 41068, Korea
| | | | - Youngshik Choe
- Korea Brain Research Institute, Daegu, 41068, Korea.
- , Daegu, Korea.
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4
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Atmakuru PS, Dhawan J. The cilium-centrosome axis in coupling cell cycle exit and cell fate. J Cell Sci 2023; 136:308872. [PMID: 37144419 DOI: 10.1242/jcs.260454] [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] [Indexed: 05/06/2023] Open
Abstract
The centrosome is an evolutionarily conserved, ancient organelle whose role in cell division was first described over a century ago. The structure and function of the centrosome as a microtubule-organizing center, and of its extracellular extension - the primary cilium - as a sensory antenna, have since been extensively studied, but the role of the cilium-centrosome axis in cell fate is still emerging. In this Opinion piece, we view cellular quiescence and tissue homeostasis from the vantage point of the cilium-centrosome axis. We focus on a less explored role in the choice between distinct forms of mitotic arrest - reversible quiescence and terminal differentiation, which play distinct roles in tissue homeostasis. We outline evidence implicating the centrosome-basal body switch in stem cell function, including how the cilium-centrosome complex regulates reversible versus irreversible arrest in adult skeletal muscle progenitors. We then highlight exciting new findings in other quiescent cell types that suggest signal-dependent coupling of nuclear and cytoplasmic events to the centrosome-basal body switch. Finally, we propose a framework for involvement of this axis in mitotically inactive cells and identify future avenues for understanding how the cilium-centrosome axis impacts central decisions in tissue homeostasis.
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Affiliation(s)
- Priti S Atmakuru
- CSIR Centre for Cellular and Molecular Biology, Hyderabad 500 007, India
| | - Jyotsna Dhawan
- CSIR Centre for Cellular and Molecular Biology, Hyderabad 500 007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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5
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de Las Heras-García L, Zabalegui I, Pampliega O. Methods to study primary cilia and autophagy in the brain. Methods Cell Biol 2023; 176:217-234. [PMID: 37164539 DOI: 10.1016/bs.mcb.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Autophagy is an intracellular catabolic pathway that allows proteins, organelles, and pathogens to be recycled. Thus, it is crucial to maintain cell homeostasis, especially important in post-mitotic cells as neurons that cannot dilute cellular damage through mitosis. In the last decade, autophagy has been connected to the primary cilium (PC), a small organelle that acts as a sensory hub and is present in most cell types, including astrocytes and neurons. In this chapter, we briefly describe the state-of-the-art of the interplay between autophagy, PC, and its implications for the brain, in healthy and pathophysiological conditions. Deregulations in autophagy can be monitored by numerous assays, both in vivo and in vitro, and so do changes in PC length/number. Here, we relate a practical and user-friendly description of immunofluorescence methods to study autophagy and PC changes in brain slices, including the tissue preparation, confocal microscopy, image analysis, and deconvolution process.
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Affiliation(s)
- Laura de Las Heras-García
- Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain; Achucarro Basque Center for Neurosciences, Leioa, Spain
| | | | - Olatz Pampliega
- Departamento de Neurociencias, Universidad del País Vasco (UPV/EHU), Leioa, Spain; Achucarro Basque Center for Neurosciences, Leioa, Spain.
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6
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Morleo M, Pezzella N, Franco B. Proteome balance in ciliopathies: the OFD1 protein example. Trends Mol Med 2023; 29:201-217. [PMID: 36494254 DOI: 10.1016/j.molmed.2022.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/04/2022] [Accepted: 11/18/2022] [Indexed: 12/12/2022]
Abstract
The balance of protein synthesis and degradation is finely regulated and influences cellular homeostasis and biological processes (e.g., embryonic development and neuronal plasticity). Recent data demonstrated that centrosomal/ciliary proteins enable proteome control in response to spatial or microenvironmental stimuli. Here, we discuss recent discoveries regarding the role in the balance of the proteome of centrosomal/ciliary proteins associated with genetic disorders known as ciliopathies. In particular, OFD1 was the first example of a ciliopathy protein controlling both protein expression and autophagic/proteasomal degradation. Understanding the role of proteome balance in the pathogenesis of the clinical manifestations of ciliopathies may pave the way to the identification of a wide range of putative novel therapeutic targets for these conditions.
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Affiliation(s)
- Manuela Morleo
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei, 34, 80078, Pozzuoli, Naples, Italy; Department of Precision Medicine, University of Campania 'Luigi Vanvitelli', Naples, Italy
| | - Nunziana Pezzella
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei, 34, 80078, Pozzuoli, Naples, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine program, University of Naples Federico II, Naples, Italy
| | - Brunella Franco
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei, 34, 80078, Pozzuoli, Naples, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine program, University of Naples Federico II, Naples, Italy; Medical Genetics, Department of Translational Medicine, University of Naples 'Federico II', Via Sergio Pansini, 80131, Naples, Italy.
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7
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Morleo M, Vieira HL, Pennekamp P, Palma A, Bento-Lopes L, Omran H, Lopes SS, Barral DC, Franco B. Crosstalk between cilia and autophagy: implication for human diseases. Autophagy 2023; 19:24-43. [PMID: 35613303 PMCID: PMC9809938 DOI: 10.1080/15548627.2022.2067383] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Macroautophagy/autophagy is a self-degradative process necessary for cells to maintain their energy balance during development and in response to nutrient deprivation. Autophagic processes are tightly regulated and have been found to be dysfunctional in several pathologies. Increasing experimental evidence points to the existence of an interplay between autophagy and cilia. Cilia are microtubule-based organelles protruding from the cell surface of mammalian cells that perform a variety of motile and sensory functions and, when dysfunctional, result in disorders known as ciliopathies. Indeed, selective autophagic degradation of ciliary proteins has been shown to control ciliogenesis and, conversely, cilia have been reported to control autophagy. Moreover, a growing number of players such as lysosomal and mitochondrial proteins are emerging as actors of the cilia-autophagy interplay. However, some of the published data on the cilia-autophagy axis are contradictory and indicate that we are just starting to understand the underlying molecular mechanisms. In this review, the current knowledge about this axis and challenges are discussed, as well as the implication for ciliopathies and autophagy-associated disorders.
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Affiliation(s)
- Manuela Morleo
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy,Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Helena L.A. Vieira
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa1169-056, Portugal,UCIBIO, Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal,Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Petra Pennekamp
- Department of General Pediatrics, University Hospital Münster, University of Münster, Münster48149, Germany,Member of the European Reference Networks ERN-LUNG, Lisbon, Portugal
| | - Alessandro Palma
- Department of Onco-hematology, Gene and Cell Therapy, Bambino Gesù Children’s Hospital - IRCCS, Rome, Italy
| | - Liliana Bento-Lopes
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa1169-056, Portugal
| | - Heymut Omran
- Department of General Pediatrics, University Hospital Münster, University of Münster, Münster48149, Germany,Member of the European Reference Networks ERN-LUNG, Lisbon, Portugal
| | - Susana S. Lopes
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa1169-056, Portugal,Member of the European Reference Networks ERN-LUNG, Lisbon, Portugal
| | - Duarte C. Barral
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa1169-056, Portugal
| | - Brunella Franco
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy,Medical Genetics, Department of Translational Medical Science, University of Naples “Federico II”, Naples, Italy,Scuola Superiore Meridionale, School for Advanced Studies, Naples, Italy,CONTACT Brunella Franco CEDOC, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa1169-056, Portugal
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8
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Claude-Taupin A, Dupont N, Codogno P. Autophagy and the primary cilium in cell metabolism: What’s upstream? Front Cell Dev Biol 2022; 10:1046248. [PMID: 36438551 PMCID: PMC9682156 DOI: 10.3389/fcell.2022.1046248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 10/25/2022] [Indexed: 11/11/2022] Open
Abstract
The maintenance of cellular homeostasis in response to extracellular stimuli, i.e., nutrient and hormone signaling, hypoxia, or mechanical forces by autophagy, is vital for the health of various tissues. The primary cilium (PC) is a microtubule-based sensory organelle that regulates the integration of several extracellular stimuli. Over the past decade, an interconnection between autophagy and PC has begun to be revealed. Indeed, the PC regulates autophagy and in turn, a selective form of autophagy called ciliophagy contributes to the regulation of ciliogenesis. Moreover, the PC regulates both mitochondrial biogenesis and lipophagy to produce free fatty acids. These two pathways converge to activate oxidative phosphorylation and produce ATP, which is mandatory for cell metabolism and membrane transport. The autophagy-dependent production of energy is fully efficient when the PC senses shear stress induced by fluid flow. In this review, we discuss the cross-talk between autophagy, the PC and physical forces in the regulation of cell biology and physiology.
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Affiliation(s)
| | - Nicolas Dupont
- *Correspondence: Aurore Claude-Taupin, ; Nicolas Dupont, ; Patrice Codogno,
| | - Patrice Codogno
- *Correspondence: Aurore Claude-Taupin, ; Nicolas Dupont, ; Patrice Codogno,
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9
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Habeck G, Schweiggert J. Proteolytic control in ciliogenesis: Temporal restriction or early initiation? Bioessays 2022; 44:e2200087. [PMID: 35739619 DOI: 10.1002/bies.202200087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 12/19/2022]
Abstract
Cellular processes are highly dependent on a dynamic proteome that undergoes structural and functional rearrangements to allow swift conversion between different cellular states. By inducing proteasomal degradation of inhibitory or stimulating factors, ubiquitylation is particularly well suited to trigger such transitions. One prominent example is the remodelling of the centrosome upon cell cycle exit, which is required for the formation of primary cilia - antenna-like structures on the surface of most cells that act as integrative hubs for various extracellular signals. Over the last decade, many reports on ubiquitin-related events involved in the regulation of ciliogenesis have emerged. Very often, these processes are considered to be initiated ad hoc, that is, directly before its effect on cilia biogenesis becomes evident. While such a temporal restriction may hold true for the majority of events, there is evidence that some of them are initiated earlier during the cell cycle. Here, we provide an overview of ubiquitin-dependent processes in ciliogenesis and discuss available data that indicate such an early onset of proteolytic regulation within preceding cell cycle stages.
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Affiliation(s)
- Gregor Habeck
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ - ZMBH Alliance, Heidelberg, Germany
| | - Jörg Schweiggert
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ - ZMBH Alliance, Heidelberg, Germany
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10
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Schweiggert J, Habeck G, Hess S, Mikus F, Beloshistov R, Meese K, Hata S, Knobeloch K, Melchior F. SCF Fbxw5 targets kinesin-13 proteins to facilitate ciliogenesis. EMBO J 2021; 40:e107735. [PMID: 34368969 PMCID: PMC8441365 DOI: 10.15252/embj.2021107735] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 11/23/2022] Open
Abstract
Microtubule depolymerases of the kinesin-13 family play important roles in various cellular processes and are frequently overexpressed in different cancer types. Despite the importance of their correct abundance, remarkably little is known about how their levels are regulated in cells. Using comprehensive screening on protein microarrays, we identified 161 candidate substrates of the multi-subunit ubiquitin E3 ligase SCFFbxw5 , including the kinesin-13 member Kif2c/MCAK. In vitro reconstitution assays demonstrate that MCAK and its closely related orthologs Kif2a and Kif2b become efficiently polyubiquitylated by neddylated SCFFbxw5 and Cdc34, without requiring preceding modifications. In cells, SCFFbxw5 targets MCAK for proteasomal degradation predominantly during G2 . While this seems largely dispensable for mitotic progression, loss of Fbxw5 leads to increased MCAK levels at basal bodies and impairs ciliogenesis in the following G1 /G0 , which can be rescued by concomitant knockdown of MCAK, Kif2a or Kif2b. We thus propose a novel regulatory event of ciliogenesis that begins already within the G2 phase of the preceding cell cycle.
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Affiliation(s)
- Jörg Schweiggert
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Gregor Habeck
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Sandra Hess
- Institute of NeuropathologyFaculty of MedicineUniversity of FreiburgFreiburgGermany
- Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Felix Mikus
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Roman Beloshistov
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Klaus Meese
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Shoji Hata
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | | | - Frauke Melchior
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
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11
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Linder B, Klein C, Hoffmann ME, Bonn F, Dikic I, Kögel D. BAG3 is a negative regulator of ciliogenesis in glioblastoma and triple-negative breast cancer cells. J Cell Biochem 2021; 123:77-90. [PMID: 34180073 DOI: 10.1002/jcb.30073] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/31/2021] [Accepted: 06/11/2021] [Indexed: 12/11/2022]
Abstract
By regulating several hallmarks of cancer, BAG3 exerts oncogenic functions in a wide variety of malignant diseases including glioblastoma (GBM) and triple-negative breast cancer (TNBC). Here we performed global proteomic/phosphoproteomic analyses of CRISPR/Cas9-mediated isogenic BAG3 knockouts of the two GBM lines U343 and U251 in comparison to parental controls. Depletion of BAG3 evoked major effects on proteins involved in ciliogenesis/ciliary function and the activity of the related kinases aurora-kinase A and CDK1. Cilia formation was significantly enhanced in BAG3 KO cells, a finding that could be confirmed in BAG3-deficient versus -proficient BT-549 TNBC cells, thus identifying a completely novel function of BAG3 as a negative regulator of ciliogenesis. Furthermore, we demonstrate that enhanced ciliogenesis and reduced expression of SNAI1 and ZEB1, two key transcription factors regulating epithelial to mesenchymal transition (EMT) are correlated to decreased cell migration, both in the GBM and TNBC BAG3 knockout cells. Our data obtained in two different tumor entities identify suppression of EMT and ciliogenesis as putative synergizing mechanisms of BAG3-driven tumor aggressiveness in therapy-resistant cancers.
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Affiliation(s)
- Benedikt Linder
- Department of Neurosurgery, Experimental Neurosurgery, University Hospital, Goethe University, Frankfurt am Main, Germany
| | - Caterina Klein
- Department of Neurosurgery, Experimental Neurosurgery, University Hospital, Goethe University, Frankfurt am Main, Germany.,Faculty of Biosciences, Goethe University, Frankfurt am Main, Germany
| | - Marina E Hoffmann
- Institute of Biochemistry II, Goethe University, Frankfurt am Main, Germany
| | - Florian Bonn
- Institute of Biochemistry II, Goethe University, Frankfurt am Main, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University, Frankfurt am Main, Germany.,Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany
| | - Donat Kögel
- Department of Neurosurgery, Experimental Neurosurgery, University Hospital, Goethe University, Frankfurt am Main, Germany.,German Cancer Consortium (DKTK), Partner Site Frankfurt, Frankfurt am Main, Germany.,German Cancer Research Center DKFZ, Heidelberg, Germany
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12
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Stokman MF, Saunier S, Benmerah A. Renal Ciliopathies: Sorting Out Therapeutic Approaches for Nephronophthisis. Front Cell Dev Biol 2021; 9:653138. [PMID: 34055783 PMCID: PMC8155538 DOI: 10.3389/fcell.2021.653138] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 04/19/2021] [Indexed: 12/13/2022] Open
Abstract
Nephronophthisis (NPH) is an autosomal recessive ciliopathy and a major cause of end-stage renal disease in children. The main forms, juvenile and adult NPH, are characterized by tubulointerstitial fibrosis whereas the infantile form is more severe and characterized by cysts. NPH is caused by mutations in over 20 different genes, most of which encode components of the primary cilium, an organelle in which important cellular signaling pathways converge. Ciliary signal transduction plays a critical role in kidney development and tissue homeostasis, and disruption of ciliary signaling has been associated with cyst formation, epithelial cell dedifferentiation and kidney function decline. Drugs have been identified that target specific signaling pathways (for example cAMP/PKA, Hedgehog, and mTOR pathways) and rescue NPH phenotypes in in vitro and/or in vivo models. Despite identification of numerous candidate drugs in rodent models, there has been a lack of clinical trials and there is currently no therapy that halts disease progression in NPH patients. This review covers the most important findings of therapeutic approaches in NPH model systems to date, including hypothesis-driven therapies and untargeted drug screens, approached from the pathophysiology of NPH. Importantly, most animal models used in these studies represent the cystic infantile form of NPH, which is less prevalent than the juvenile form. It appears therefore important to develop new models relevant for juvenile/adult NPH. Alternative non-orthologous animal models and developments in patient-based in vitro model systems are discussed, as well as future directions in personalized therapy for NPH.
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Affiliation(s)
- Marijn F Stokman
- Department of Genetics, University Medical Center Utrecht, Utrecht, Netherlands
- Université de Paris, Imagine Institute, Laboratory of Inherited Kidney Diseases, INSERM UMR 1163, Paris, France
| | - Sophie Saunier
- Université de Paris, Imagine Institute, Laboratory of Inherited Kidney Diseases, INSERM UMR 1163, Paris, France
| | - Alexandre Benmerah
- Université de Paris, Imagine Institute, Laboratory of Inherited Kidney Diseases, INSERM UMR 1163, Paris, France
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Boukhalfa A, Roccio F, Dupont N, Codogno P, Morel E. The autophagy protein ATG16L1 cooperates with IFT20 and INPP5E to regulate the turnover of phosphoinositides at the primary cilium. Cell Rep 2021; 35:109045. [PMID: 33910006 DOI: 10.1016/j.celrep.2021.109045] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/22/2021] [Accepted: 04/07/2021] [Indexed: 02/07/2023] Open
Abstract
The primary cilium (PC) regulates signalization linked to external stress sensing. Previous works established a functional interplay between the PC and the autophagic machinery. When ciliogenesis is promoted by serum deprivation, the autophagy protein ATG16L1 and the ciliary protein IFT20 are co-transported to the PC. Here, we demonstrate that IFT20 and ATG16L1 are part of the same complex requiring the WD40 domain of ATG16L1 and a Y-E-F-I motif in IFT20. We show that ATG16L1-deficient cells exhibit aberrant ciliary structures, which accumulate PI4,5P2, whereas PI4P, a lipid normally concentrated in the PC, is absent. Finally, we demonstrate that INPP5E, a phosphoinositide-associated phosphatase responsible for PI4P generation, interacts with ATG16L1 and that a perturbation of the ATG16L1/IFT20 complex alters its trafficking to the PC. Altogether, our results reveal a function of ATG16L1 in ciliary lipid and protein trafficking, thus directly contributing to proper PC dynamics and functions.
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Affiliation(s)
- Asma Boukhalfa
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France
| | - Federica Roccio
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France
| | - Nicolas Dupont
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France
| | - Patrice Codogno
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France.
| | - Etienne Morel
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France.
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Fernandes de Oliveira LM, Steindorff M, Darisipudi MN, Mrochen DM, Trübe P, Bröker BM, Brönstrup M, Tegge W, Holtfreter S. Discovery of Staphylococcus aureus Adhesion Inhibitors by Automated Imaging and Their Characterization in a Mouse Model of Persistent Nasal Colonization. Microorganisms 2021; 9:microorganisms9030631. [PMID: 33803564 PMCID: PMC8002927 DOI: 10.3390/microorganisms9030631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/10/2021] [Accepted: 03/14/2021] [Indexed: 01/26/2023] Open
Abstract
Due to increasing mupirocin resistance, alternatives for Staphylococcus aureus nasal decolonization are urgently needed. Adhesion inhibitors are promising new preventive agents that may be less prone to induce resistance, as they do not interfere with the viability of S. aureus and therefore exert less selection pressure. We identified promising adhesion inhibitors by screening a library of 4208 compounds for their capacity to inhibit S. aureus adhesion to A-549 epithelial cells in vitro in a novel automated, imaging-based assay. The assay quantified DAPI-stained nuclei of the host cell; attached bacteria were stained with an anti-teichoic acid antibody. The most promising candidate, aurintricarboxylic acid (ATA), was evaluated in a novel persistent S. aureus nasal colonization model using a mouse-adapted S. aureus strain. Colonized mice were treated intranasally over 7 days with ATA using a wide dose range (0.5–10%). Mupirocin completely eliminated the bacteria from the nose within three days of treatment. In contrast, even high concentrations of ATA failed to eradicate the bacteria. To conclude, our imaging-based assay and the persistent colonization model provide excellent tools to identify and validate new drug candidates against S. aureus nasal colonization. However, our first tested candidate ATA failed to induce S. aureus decolonization.
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Affiliation(s)
- Liliane Maria Fernandes de Oliveira
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
| | - Marina Steindorff
- Helmholtz Centre for Infection Research, Department of Chemical Biology, 38124 Braunschweig, Germany (M.B.)
| | - Murthy N. Darisipudi
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
| | - Daniel M. Mrochen
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
| | - Patricia Trübe
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
| | - Barbara M. Bröker
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
| | - Mark Brönstrup
- Helmholtz Centre for Infection Research, Department of Chemical Biology, 38124 Braunschweig, Germany (M.B.)
| | - Werner Tegge
- Helmholtz Centre for Infection Research, Department of Chemical Biology, 38124 Braunschweig, Germany (M.B.)
- Correspondence: (W.T.); (S.H.)
| | - Silva Holtfreter
- Institute of Immunology and Transfusion Medicine, Department of Immunology, University Medicine Greifswald, 17475 Greifswald, Germany; (L.M.F.d.O.); (M.N.D.); (D.M.M.); (P.T.); (B.M.B.)
- Correspondence: (W.T.); (S.H.)
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15
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Tasca A, Helmstädter M, Brislinger MM, Haas M, Mitchell B, Walentek P. Notch signaling induces either apoptosis or cell fate change in multiciliated cells during mucociliary tissue remodeling. Dev Cell 2021; 56:525-539.e6. [PMID: 33400913 PMCID: PMC7904641 DOI: 10.1016/j.devcel.2020.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 10/13/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023]
Abstract
Multiciliated cells (MCCs) are extremely highly differentiated, presenting >100 cilia and basal bodies. Therefore, MCC fate is thought to be terminal and irreversible. We analyzed how MCCs are removed from the airway-like mucociliary Xenopus epidermis during developmental tissue remodeling. We found that a subset of MCCs undergoes lateral line-induced apoptosis, but that the majority coordinately trans-differentiate into goblet secretory cells. Both processes are dependent on Notch signaling, while the cellular response to Notch is modulated by Jak/STAT, thyroid hormone, and mTOR signaling. At the cellular level, trans-differentiation is executed through the loss of ciliary gene expression, including foxj1 and pcm1, altered proteostasis, cilia retraction, basal body elimination, as well as the initiation of mucus production and secretion. Our work describes two modes for MCC loss during vertebrate development, the signaling regulation of these processes, and demonstrates that even cells with extreme differentiation features can undergo direct fate conversion.
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Affiliation(s)
- Alexia Tasca
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, 79106 Freiburg, Germany; Center for Biological Systems Analysis, University of Freiburg, 79104 Freiburg, Germany
| | - Martin Helmstädter
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, 79106 Freiburg, Germany
| | - Magdalena Maria Brislinger
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, 79106 Freiburg, Germany; Center for Biological Systems Analysis, University of Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Maximilian Haas
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, 79106 Freiburg, Germany; Center for Biological Systems Analysis, University of Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Brian Mitchell
- Department of Cell and Developmental Biology, Lurie Comprehensive Cancer Center, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Peter Walentek
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, 79106 Freiburg, Germany; Center for Biological Systems Analysis, University of Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
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Walentek P. Xenopus epidermal and endodermal epithelia as models for mucociliary epithelial evolution, disease, and metaplasia. Genesis 2021; 59:e23406. [PMID: 33400364 DOI: 10.1002/dvg.23406] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 11/08/2022]
Abstract
The Xenopus embryonic epidermis is a powerful model to study mucociliary biology, development, and disease. Particularly, the Xenopus system is being used to elucidate signaling pathways, transcription factor functions, and morphogenetic mechanisms regulating cell fate specification, differentiation and cell function. Thereby, Xenopus research has provided significant insights into potential underlying molecular mechanisms for ciliopathies and chronic airway diseases. Recent studies have also established the embryonic epidermis as a model for mucociliary epithelial remodeling, multiciliated cell trans-differentiation, cilia loss, and mucus secretion. Additionally, the tadpole foregut epithelium is lined by a mucociliary epithelium, which shows remarkable features resembling mammalian airway epithelia, including its endodermal origin and a variable cell type composition along the proximal-distal axis. This review aims to summarize the advantages of the Xenopus epidermis for mucociliary epithelial biology and disease modeling. Furthermore, the potential of the foregut epithelium as novel mucociliary model system is being highlighted. Additional perspectives are presented on how to expand the range of diseases that can be modeled in the frog system, including proton pump inhibitor-associated pneumonia as well as metaplasia in epithelial cells of the airway and the gastroesophageal region.
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Affiliation(s)
- Peter Walentek
- Renal Division, Department of Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Freiburg, Germany.,CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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Çetin G, Klafack S, Studencka-Turski M, Krüger E, Ebstein F. The Ubiquitin-Proteasome System in Immune Cells. Biomolecules 2021; 11:biom11010060. [PMID: 33466553 PMCID: PMC7824874 DOI: 10.3390/biom11010060] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/16/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
The ubiquitin–proteasome system (UPS) is the major intracellular and non-lysosomal protein degradation system. Thanks to its unique capacity of eliminating old, damaged, misfolded, and/or regulatory proteins in a highly specific manner, the UPS is virtually involved in almost all aspects of eukaryotic life. The critical importance of the UPS is particularly visible in immune cells which undergo a rapid and profound functional remodelling upon pathogen recognition. Innate and/or adaptive immune activation is indeed characterized by a number of substantial changes impacting various cellular processes including protein homeostasis, signal transduction, cell proliferation, and antigen processing which are all tightly regulated by the UPS. In this review, we summarize and discuss recent progress in our understanding of the molecular mechanisms by which the UPS contributes to the generation of an adequate immune response. In this regard, we also discuss the consequences of UPS dysfunction and its role in the pathogenesis of recently described immune disorders including cancer and auto-inflammatory diseases.
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The cellular basis of organ failure in sepsis-signaling during damage and repair processes. Med Klin Intensivmed Notfmed 2020; 115:4-9. [PMID: 32236799 PMCID: PMC7220871 DOI: 10.1007/s00063-020-00673-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 01/14/2020] [Indexed: 12/27/2022]
Abstract
Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. This definition, updated in 2016, shifted the conceptual focus from exclusive attention to the systemic inflammatory response toward the multifactorial tissue damage that occurs during the progression of infection to sepsis and shock. Whereas targeting the inflammatory host response to infection did not translate into improved clinical management of sepsis, recent findings might shed new light on the maladaptive host–pathogen interaction in sepsis and pave the way for “theranostic” interventions. In addition to the well-known resistance responses of the immune system that result in pathogen clearance, “disease tolerance” has recently been acknowledged as a coping mechanism of presumably equal importance. We propose that both defense mechanisms, “resistance” and “disease tolerance”, can get out of control in sepsis. Whereas excessive activation of resistance pathways propagates tissue damage via immunopathology, an inappropriate “tolerance” might entail immunoparalysis accompanied by fulminant, recurrent or persisting infection. The review introduces key signaling processes involved in infection-induced “resistance” and “tolerance”. We propose that elaboration of these signaling pathways allows novel insights into sepsis-associated tissue damage and repair processes. Moreover theranostic opportunities for the specific treatment of sepsis-related hyperinflammation or immunoparalysis will be introduced. Agents specifically affecting either hyperinflammation or immunoparalysis in the course of sepsis might add to the therapeutic toolbox of personalized care in the field of organ dysfunction caused by infection. (This article is freely available.)
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Zhang H, Tan YP, Zhao L, Wang L, Fu NJ, Zheng SP, Shen XF. Anticancer activity of dietary xanthone α-mangostin against hepatocellular carcinoma by inhibition of STAT3 signaling via stabilization of SHP1. Cell Death Dis 2020; 11:63. [PMID: 31980595 PMCID: PMC6981176 DOI: 10.1038/s41419-020-2227-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 02/05/2023]
Abstract
Hepatocellular carcinoma (HCC) is one of the most lethal human cancers worldwide. The dietary xanthone α-mangostin (α-MGT) exhibits potent anti-tumor effects in vitro and in vivo. However, the anti-HCC effects of α-MGT and their underlying mechanisms are still vague. Aberrant activation of signal transducer and activator of transcription 3 (STAT3) is involved in the progression of HCC. We therefore investigated whether α-MGT inhibited the activation of STAT3 and thereby exhibits its anti-HCC effects. In this study, we found that α-MGT significantly suppressed cell proliferation, induced cell cycle arrest, and triggered apoptosis in HCC cells, including HepG2, SK-Hep-1, Huh7, and SMMC-7721 cells in vitro, as well as inhibiting tumor growth in nude mice bearing HepG2 or SK-Hep-1 xenografts. Furthermore, α-MGT potently inhibited the constitutive and inducible activation of STAT3 in HCC cells. In addition, α-MGT also suppressed IL-6-induced dimerization and nuclear translocation of STAT3, which led to inhibition of the expression of STAT3-regulated genes at both mRNA and protein levels. Mechanistically, α-MGT exhibited effective inhibition of the activation of STAT3’s upstream kinases, including JAK2, Src, ERK, and Akt. Importantly, α-MGT increased the protein level of Src homology region 2 domain-containing phosphatase-1 (SHP1), which is a key negative regulator of the STAT3 signaling pathway. Furthermore, α-MGT enhanced the stabilization of SHP1 by inhibiting its degradation mediated by the ubiquitin–proteasome pathway. Knockdown of SHP1 using siRNA obviously prevented the α-MGT-mediated inhibition of the activation of STAT3 and proliferation of HCC cells. In summary, α-MGT exhibited a potent anti-HCC effect by blocking the STAT3 signaling pathway via the suppression of the degradation of SHP1 induced by the ubiquitin–proteasome pathway. These findings also suggested the potential of dietary derived α-MGT in HCC therapy.
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Affiliation(s)
- Hai Zhang
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Yu-Ping Tan
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu, China
| | - Lin Zhao
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu, China
| | - Lun Wang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Nai-Jie Fu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Song-Ping Zheng
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China
| | - Xiao-Fei Shen
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Ministry of Education), West China Second University Hospital, Sichuan University, Chengdu, China.
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Finetti F, Capitani N, Baldari CT. Emerging Roles of the Intraflagellar Transport System in the Orchestration of Cellular Degradation Pathways. Front Cell Dev Biol 2019; 7:292. [PMID: 31803744 PMCID: PMC6877659 DOI: 10.3389/fcell.2019.00292] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/06/2019] [Indexed: 12/27/2022] Open
Abstract
Ciliated cells exploit a specific transport system, the intraflagellar transport (IFT) system, to ensure the traffic of molecules from the cell body to the cilium. However, it is now clear that IFT activity is not restricted to cilia-related functions. This is strikingly exemplified by the observation that IFT proteins play important roles in cells lacking a primary cilium, such as lymphocytes. Indeed, in T cells the IFT system regulates the polarized transport of endosome-associated T cell antigen receptors and signaling mediators during assembly of the immune synapse, a specialized interface that forms on encounter with a cognate antigen presenting cell and on which T cell activation and effector function crucially depend. Cellular degradation pathways have recently emerged as new extraciliary functions of the IFT system. IFT proteins have been demonstrated to regulate autophagy in ciliated cells through their ability to recruit the autophagy machinery to the base of the cilium. We have now implicated the IFT component IFT20 in another central degradation process that also controls the latest steps in autophagy, namely lysosome function, by regulating the cation-independent mannose-6-phosphate receptor (CI-MPR)-dependent lysosomal targeting of acid hydrolases. This involves the ability of IFT20 to act as an adaptor coupling the CI-MPR to dynein for retrograde transport to the trans-Golgi network. In this short review we will discuss the emerging roles of IFT proteins in cellular degradation pathways.
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Affiliation(s)
| | - Nagaja Capitani
- Department of Life Sciences, University of Siena, Siena, Italy
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