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Masters H, Wang S, Tu C, Nguyen Q, Sha Y, Karikomi MK, Fung PSR, Tran B, Martel C, Kwang N, Neel M, Jaime OG, Espericueta V, Johnson BA, Kessenbrock K, Nie Q, Monuki ES. Sequential emergence and contraction of epithelial subtypes in the prenatal human choroid plexus revealed by a stem cell model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.12.598747. [PMID: 38948782 PMCID: PMC11212933 DOI: 10.1101/2024.06.12.598747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Despite the major roles of choroid plexus epithelial cells (CPECs) in brain homeostasis and repair, their developmental lineage and diversity remain undefined. In simplified differentiations from human pluripotent stem cells, derived CPECs (dCPECs) displayed canonical properties and dynamic multiciliated phenotypes that interacted with Aβ uptake. Single dCPEC transcriptomes over time correlated well with human organoid and fetal CPECs, while pseudotemporal and cell cycle analyses highlighted the direct CPEC origin from neuroepithelial cells. In addition, time series analyses defined metabolic (type 1) and ciliogenic dCPECs (type 2) at early timepoints, followed by type 1 diversification into anabolic-secretory (type 1a) and catabolic-absorptive subtypes (type 1b) as type 2 cells contracted. These temporal patterns were then confirmed in independent derivations and mapped to prenatal stages using human tissues. In addition to defining the prenatal lineage of human CPECs, these findings suggest new dynamic models of ChP support for the developing human brain.
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2
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Yang K, Fu W, Deng M, Li X, Wu M, Wang Y. The sphingolipids change in exosomes from cancer patients and association between exosome release and sphingolipids level based on a pseudotargeted lipidomics method. Anal Chim Acta 2024; 1305:342527. [PMID: 38677835 DOI: 10.1016/j.aca.2024.342527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/01/2024] [Accepted: 03/24/2024] [Indexed: 04/29/2024]
Abstract
The lipid based ESCRT-independent mechanism, which contributes to MVB formation, is one of the crucial procedures in exosome biogenesis. n-SMase is a key lipid metabolism enzyme in this mechanism and can induce the hydrolysis of sphingomyelins (SMs) to ceramides (Cers), thereby promoting the formation of ILVs inside MVBs. Therefore, the regulation of n-SMase can realize the alteration in exosome release. According to the fact that cancer-associated cells have a tendency to release more exosomes than healthy cells, lipid extracts in exosomes from healthy volunteers, HCC and ICC patients were analyzed by a novel pseudotargeted lipidomics method focused on sphingolipids (SLs) to explore whether cancer-related features regulate the release of exosomes through the above pathway. Multivariate analysis based on the SLs expression could distinguish three groups well indicated that the SLs expression among the three groups were different. In cancer groups, two species of critical Cers were up-regulated, denoted as Cer (d18:1_16:0) and Cer (d18:1_18:0), while 55 kinds of SLs were down-regulated, including 40 species of SMs, such as SM (d18:1_16:0), SM (d18:1_18:1) and SM (d18:1_24:0). Meanwhile, several species of SM/Cer exhibited significant down-regulation. This substantial enhancement of the SMs hydrolysis to Cers process during exosome biogenesis suggested that cancer-related features may potentially promote an increase in exosome release through ESCRT-independent mechanism. Moreover, differential SLs have a capability of becoming potential biomarkers for disease diagnosis and classification with an AUC value of 0.9884 or 0.9806 for the comparison between healthy group and HCC or ICC groups, respectively. In addition, an association analysis conducted on the cell lines showed that changes in the SM/Cer contents in cells and their exosomes were negatively correlated with the levels of released exosomes, implied the regulation of exosome release levels can be achieved by modulating n-SMase and subsequent SL expression.
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Affiliation(s)
- Kaige Yang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wenchang Fu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Mengjiao Deng
- Department of Pharmacy, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China
| | - Xinyan Li
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Mingyuan Wu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yan Wang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Seal A, Hughes M, Wei F, Pugazhendhi AS, Ngo C, Ruiz J, Schwartzman JD, Coathup MJ. Sphingolipid-Induced Bone Regulation and Its Emerging Role in Dysfunction Due to Disease and Infection. Int J Mol Sci 2024; 25:3024. [PMID: 38474268 DOI: 10.3390/ijms25053024] [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: 02/09/2024] [Revised: 03/02/2024] [Accepted: 03/04/2024] [Indexed: 03/14/2024] Open
Abstract
The human skeleton is a metabolically active system that is constantly regenerating via the tightly regulated and highly coordinated processes of bone resorption and formation. Emerging evidence reveals fascinating new insights into the role of sphingolipids, including sphingomyelin, sphingosine, ceramide, and sphingosine-1-phosphate, in bone homeostasis. Sphingolipids are a major class of highly bioactive lipids able to activate distinct protein targets including, lipases, phosphatases, and kinases, thereby conferring distinct cellular functions beyond energy metabolism. Lipids are known to contribute to the progression of chronic inflammation, and notably, an increase in bone marrow adiposity parallel to elevated bone loss is observed in most pathological bone conditions, including aging, rheumatoid arthritis, osteoarthritis, and osteomyelitis. Of the numerous classes of lipids that form, sphingolipids are considered among the most deleterious. This review highlights the important primary role of sphingolipids in bone homeostasis and how dysregulation of these bioactive metabolites appears central to many chronic bone-related diseases. Further, their contribution to the invasion, virulence, and colonization of both viral and bacterial host cell infections is also discussed. Many unmet clinical needs remain, and data to date suggest the future use of sphingolipid-targeted therapy to regulate bone dysfunction due to a variety of diseases or infection are highly promising. However, deciphering the biochemical and molecular mechanisms of this diverse and extremely complex sphingolipidome, both in terms of bone health and disease, is considered the next frontier in the field.
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Affiliation(s)
- Anouska Seal
- Biionix Cluster, University of Central Florida, Orlando, FL 32827, USA
| | - Megan Hughes
- School of Biosciences, Cardiff University, Cardiff CF10 3AT, UK
| | - Fei Wei
- Biionix Cluster, University of Central Florida, Orlando, FL 32827, USA
- College of Medicine, University of Central Florida, Orlando, FL 32827, USA
| | - Abinaya S Pugazhendhi
- Biionix Cluster, University of Central Florida, Orlando, FL 32827, USA
- College of Medicine, University of Central Florida, Orlando, FL 32827, USA
| | - Christopher Ngo
- Biionix Cluster, University of Central Florida, Orlando, FL 32827, USA
- College of Medicine, University of Central Florida, Orlando, FL 32827, USA
| | - Jonathan Ruiz
- College of Medicine, University of Central Florida, Orlando, FL 32827, USA
| | | | - Melanie J Coathup
- Biionix Cluster, University of Central Florida, Orlando, FL 32827, USA
- College of Medicine, University of Central Florida, Orlando, FL 32827, USA
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Inskeep KA, Crase B, Stottmann RW. SMPD4 mediated sphingolipid metabolism regulates brain and primary cilia development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.15.571873. [PMID: 38168190 PMCID: PMC10760124 DOI: 10.1101/2023.12.15.571873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Genetic variants in multiple sphingolipid biosynthesis genes cause human brain disorders. A recent study collected patients from twelve unrelated families with variants in the gene SMPD4 , a neutral sphingomyelinase which metabolizes sphingomyelin into ceramide at an early stage of the biosynthesis pathway. These patients have severe developmental brain malformations including microcephaly and cerebellar hypoplasia. However, the mechanism of SMPD4 was not known and we pursued a new mouse model. We hypothesized that the role of SMPD4 in producing ceramide is important for making primary cilia, a crucial organelle mediating cellular signaling. We found that the mouse model has cerebellar hypoplasia due to failure of Purkinje cell development. Human induced pluripotent stem cells exhibit neural progenitor cell death and have shortened primary cilia which is rescued by adding exogenous ceramide. SMPD4 production of ceramide is crucial for human brain development.
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Tian JL, Huang CW, Eslami F, Mannino MP, Mai RL, Hart GW. Regulation of Primary Cilium Length by O-GlcNAc during Neuronal Development in a Human Neuron Model. Cells 2023; 12:1520. [PMID: 37296641 PMCID: PMC10252524 DOI: 10.3390/cells12111520] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/25/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
The primary cilium plays critical roles in the homeostasis and development of neurons. Recent studies demonstrate that cilium length is regulated by the metabolic state of cells, as dictated by processes such as glucose flux and O-GlcNAcylation (OGN). The study of cilium length regulation during neuron development, however, has been an area left largely unexplored. This project aims to elucidate the roles of O-GlcNAc in neuronal development through its regulation of the primary cilium. Here, we present findings suggesting that OGN levels negatively regulate cilium length on differentiated cortical neurons derived from human-induced pluripotent stem cells. In neurons, cilium length increased significantly during maturation (after day 35), while OGN levels began to drop. Long-term perturbation of OGN via drugs, which inhibit or promote its cycling, during neuron development also have varying effects. Diminishing OGN levels increases cilium length until day 25, when neural stem cells expand and undergo early neurogenesis, before causing cell cycle exit defects and multinucleation. Elevating OGN levels induces greater primary cilia assembly but ultimately results in the development of premature neurons, which have higher insulin sensitivity. These results indicate that OGN levels and primary cilium length are jointly critical in proper neuron development and function. Understanding the interplays between these two nutrient sensors, O-GlcNAc and the primary cilium, during neuron development is important in paving connections between dysfunctional nutrient-sensing and early neurological disorders.
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Affiliation(s)
- Jie L. Tian
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Chia-Wei Huang
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Farzad Eslami
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Michael Philip Mannino
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Rebecca Lee Mai
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biology, University of Georgia, Athens, GA 30602, USA
| | - Gerald W. Hart
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; (C.-W.H.); (F.E.); (M.P.M.); (R.L.M.)
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
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Cappuccio G, Khalil SM, Osenberg S, Li F, Maletic-Savatic M. Mass spectrometry imaging as an emerging tool for studying metabolism in human brain organoids. Front Mol Biosci 2023; 10:1181965. [PMID: 37304070 PMCID: PMC10251497 DOI: 10.3389/fmolb.2023.1181965] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Human brain organoids are emerging models to study human brain development and pathology as they recapitulate the development and characteristics of major neural cell types, and enable manipulation through an in vitro system. Over the past decade, with the advent of spatial technologies, mass spectrometry imaging (MSI) has become a prominent tool for metabolic microscopy, providing label-free, non-targeted molecular and spatial distribution information of the metabolites within tissue, including lipids. This technology has never been used for studies of brain organoids and here, we set out to develop a standardized protocol for preparation and mass spectrometry imaging of human brain organoids. We present an optimized and validated sample preparation protocol, including sample fixation, optimal embedding solution, homogenous deposition of matrices, data acquisition and processing to maximize the molecular information derived from mass spectrometry imaging. We focus on lipids in organoids, as they play critical roles during cellular and brain development. Using high spatial and mass resolution in positive- and negative-ion modes, we detected 260 lipids in the organoids. Seven of them were uniquely localized within the neurogenic niches or rosettes as confirmed by histology, suggesting their importance for neuroprogenitor proliferation. We observed a particularly striking distribution of ceramide-phosphoethanolamine CerPE 36:1; O2 which was restricted within rosettes and of phosphatidyl-ethanolamine PE 38:3, which was distributed throughout the organoid tissue but not in rosettes. This suggests that ceramide in this particular lipid species might be important for neuroprogenitor biology, while its removal may be important for terminal differentiation of their progeny. Overall, our study establishes the first optimized experimental pipeline and data processing strategy for mass spectrometry imaging of human brain organoids, allowing direct comparison of lipid signal intensities and distributions in these tissues. Further, our data shed new light on the complex processes that govern brain development by identifying specific lipid signatures that may play a role in cell fate trajectories. Mass spectrometry imaging thus has great potential in advancing our understanding of early brain development as well as disease modeling and drug discovery.
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Affiliation(s)
- Gerarda Cappuccio
- Department of Pediatrics–Neurology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Saleh M. Khalil
- Department of Pediatrics–Neurology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Sivan Osenberg
- Department of Pediatrics–Neurology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
| | - Feng Li
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX, United States
| | - Mirjana Maletic-Savatic
- Department of Pediatrics–Neurology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX, United States
- Center for Drug Discovery, Baylor College of Medicine, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
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7
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Custodia A, Romaus-Sanjurjo D, Aramburu-Núñez M, Álvarez-Rafael D, Vázquez-Vázquez L, Camino-Castiñeiras J, Leira Y, Pías-Peleteiro JM, Aldrey JM, Sobrino T, Ouro A. Ceramide/Sphingosine 1-Phosphate Axis as a Key Target for Diagnosis and Treatment in Alzheimer’s Disease and Other Neurodegenerative Diseases. Int J Mol Sci 2022; 23:ijms23158082. [PMID: 35897658 PMCID: PMC9331765 DOI: 10.3390/ijms23158082] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/15/2022] [Accepted: 07/20/2022] [Indexed: 12/10/2022] Open
Abstract
Alzheimer’s disease (AD) is considered the most prevalent neurodegenerative disease and the leading cause of dementia worldwide. Sphingolipids, such as ceramide or sphingosine 1-phosphate, are bioactive molecules implicated in structural and signaling functions. Metabolic dysfunction in the highly conserved pathways to produce sphingolipids may lead to or be a consequence of an underlying disease. Recent studies on transcriptomics and sphingolipidomics have observed alterations in sphingolipid metabolism of both enzymes and metabolites involved in their synthesis in several neurodegenerative diseases, including AD. In this review, we highlight the most relevant findings related to ceramide and neurodegeneration, with a special focus on AD.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Tomás Sobrino
- Correspondence: (T.S.); (A.O.); Tel.: +34-981951098 (T.S.); +34-664326589 (A.O.)
| | - Alberto Ouro
- Correspondence: (T.S.); (A.O.); Tel.: +34-981951098 (T.S.); +34-664326589 (A.O.)
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8
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Aguirre RS, Kulkarni A, Becker MW, Lei X, Sarkar S, Ramanadham S, Phelps EA, Nakayasu ES, Sims EK, Mirmira RG. Extracellular vesicles in β cell biology: Role of lipids in vesicle biogenesis, cargo, and intercellular signaling. Mol Metab 2022; 63:101545. [PMID: 35817393 PMCID: PMC9294332 DOI: 10.1016/j.molmet.2022.101545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/03/2022] [Accepted: 07/05/2022] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Type 1 diabetes (T1D) is a complex autoimmune disorder whose pathogenesis involves an intricate interplay between β cells of the pancreatic islet, other islet cells, and cells of the immune system. Direct intercellular communication within the islet occurs via cell surface proteins and indirect intercellular communication has traditionally been seen as occurring via secreted proteins (e.g., endocrine hormones and cytokines). However, recent literature suggests that extracellular vesicles (EVs) secreted by β cells constitute an additional and biologically important mechanism for transmitting signals to within the islet. SCOPE OF REVIEW This review summarizes the general mechanisms of EV formation, with a particular focus on how lipids and lipid signaling pathways influence their formation and cargo. We review the implications of EV release from β cells for T1D pathogenesis, how EVs and their cargo might be leveraged as biomarkers of this process, and how EVs might be engineered as a therapeutic candidate to counter T1D outcomes. MAJOR CONCLUSIONS Islet β cells have been viewed as initiators and propagators of the cellular circuit giving rise to autoimmunity in T1D. In this context, emerging literature suggests that EVs may represent a conduit for communication that holds more comprehensive messaging about the β cells from which they arise. As the field of EV biology advances, it opens the possibility that intervening with EV formation and cargo loading could be a novel disease-modifying approach in T1D.
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Affiliation(s)
| | - Abhishek Kulkarni
- Department of Medicine and the Kovler Diabetes Center, The University of Chicago, Chicago, IL, USA
| | - Matthew W. Becker
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology & The Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Soumyadeep Sarkar
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology & The Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Edward A. Phelps
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Ernesto S. Nakayasu
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Emily K. Sims
- Department of Pediatrics and the Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Raghavendra G. Mirmira
- Department of Medicine and the Kovler Diabetes Center, The University of Chicago, Chicago, IL, USA,Corresponding author. 900 E. 57th St., KCBD 8130, Chicago, IL, 60637, USA.
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9
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Dutta P, Ray K. Ciliary membrane, localised lipid modification and cilia function. J Cell Physiol 2022; 237:2613-2631. [PMID: 35661356 DOI: 10.1002/jcp.30787] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 05/06/2022] [Accepted: 05/11/2022] [Indexed: 11/08/2022]
Abstract
Cilium, a tiny microtubule-based cellular appendage critical for cell signalling and physiology, displays a large variety of receptors. The composition and turnover of ciliary lipids and receptors determine cell behaviour. Due to the exclusion of ribosomal machinery and limited membrane area, a cilium needs adaptive logistics to actively reconstitute the lipid and receptor compositions during development and differentiation. How is this dynamicity generated? Here, we examine whether, along with the Intraflagellar-Transport, targeted changes in sector-wise lipid composition could control the receptor localisation and functions in the cilia. We discuss how an interplay between ciliary lipid composition, localised lipid modification, and receptor function could contribute to cilia growth and signalling. We argue that lipid modification at the cell-cilium interface could generate an added thrust for a selective exchange of membrane lipids and the transmembrane and membrane-associated proteins.
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Affiliation(s)
- Priya Dutta
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Krishanu Ray
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
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10
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Li S, Kim HE. Implications of Sphingolipids on Aging and Age-Related Diseases. FRONTIERS IN AGING 2022; 2:797320. [PMID: 35822041 PMCID: PMC9261390 DOI: 10.3389/fragi.2021.797320] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 12/31/2021] [Indexed: 01/14/2023]
Abstract
Aging is a process leading to a progressive loss of physiological integrity and homeostasis, and a primary risk factor for many late-onset chronic diseases. The mechanisms underlying aging have long piqued the curiosity of scientists. However, the idea that aging is a biological process susceptible to genetic manipulation was not well established until the discovery that the inhibition of insulin/IGF-1 signaling extended the lifespan of C. elegans. Although aging is a complex multisystem process, López-Otín et al. described aging in reference to nine hallmarks of aging. These nine hallmarks include: genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. Due to recent advances in lipidomic, investigation into the role of lipids in biological aging has intensified, particularly the role of sphingolipids (SL). SLs are a diverse group of lipids originating from the Endoplasmic Reticulum (ER) and can be modified to create a vastly diverse group of bioactive metabolites that regulate almost every major cellular process, including cell cycle regulation, senescence, proliferation, and apoptosis. Although SL biology reaches all nine hallmarks of aging, its contribution to each hallmark is disproportionate. In this review, we will discuss in detail the major contributions of SLs to the hallmarks of aging and age-related diseases while also summarizing the importance of their other minor but integral contributions.
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Affiliation(s)
- Shengxin Li
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, TX, United States
- Graduate School of Biomedical Sciences, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Hyun-Eui Kim
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, TX, United States
- Graduate School of Biomedical Sciences, University of Texas MD Anderson Cancer Center, Houston, TX, United States
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11
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Sivakumar S, Qi S, Cheng N, Sathe AA, Kanchwala M, Kumar A, Evers BM, Xing C, Yu H. TP53 promotes lineage commitment of human embryonic stem cells through ciliogenesis and sonic hedgehog signaling. Cell Rep 2022; 38:110395. [PMID: 35172133 PMCID: PMC8904926 DOI: 10.1016/j.celrep.2022.110395] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 11/07/2021] [Accepted: 01/24/2022] [Indexed: 12/13/2022] Open
Abstract
Aneuploidy, defective differentiation, and inactivation of the tumor suppressor TP53 all occur frequently during tumorigenesis. Here, we probe the potential links among these cancer traits by inactivating TP53 in human embryonic stem cells (hESCs). TP53-/- hESCs exhibit increased proliferation rates, mitotic errors, and low-grade structural aneuploidy; produce poorly differentiated immature teratomas in mice; and fail to differentiate into neural progenitor cells (NPCs) in vitro. Genome-wide CRISPR screen reveals requirements of ciliogenesis and sonic hedgehog (Shh) pathways for hESC differentiation into NPCs. TP53 deletion causes abnormal ciliogenesis in neural rosettes. In addition to restraining cell proliferation through CDKN1A, TP53 activates the transcription of BBS9, which encodes a ciliogenesis regulator required for proper Shh signaling and NPC formation. This developmentally regulated transcriptional program of TP53 promotes ciliogenesis, restrains Shh signaling, and commits hESCs to neural lineages.
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Affiliation(s)
- Sushama Sivakumar
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Shutao Qi
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China; School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
| | - Ningyan Cheng
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Adwait A Sathe
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Mohammed Kanchwala
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashwani Kumar
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Bret M Evers
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Chao Xing
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hongtao Yu
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA; Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China; School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China.
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12
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Wu Q, Zhang H, Sun S, Wang L, Sun S. Extracellular vesicles and immunogenic stress in cancer. Cell Death Dis 2021; 12:894. [PMID: 34599143 PMCID: PMC8486873 DOI: 10.1038/s41419-021-04171-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/22/2021] [Accepted: 09/15/2021] [Indexed: 01/08/2023]
Abstract
Tumor progression requires bidirectional cell-to-cell communication within a complex tumor microenvironment (TME). Extracellular vesicles (EVs) as carriers have the capacity to shuttle regulatory molecules, including nucleic acids, proteins, and lipids, between cancer cells and multiple stromal cells, inducing remarkable phenotypic alterations in the TME. Recently proposed the concept “immunogenic stress”, which means in some stressed microenvironment, cancer cells can release EVs containing specific immunoregulatory mediators, depending on the initiating stress-associated pathway, thereby provoking the changes of immune status in the TME. Considerable evidence has revealed that the intracellular mechanisms underlying the response to diverse stresses are mainly autophagy, endoplasmic reticulum (ER) stress reactions and the DNA damage response (DDR). In addition, the activation of immunogenic stress responses endows hosts with immune surveillance capacity; in contrast, several cargoes in EVs under immunogenic stress trigger a passive immune response by mediating the function of immune cells. This review discusses the current understanding of the immunogenic stress pathways in cancer and describes the interrelation between EVs and immunogenic stress to propose potential treatment strategies and biomarkers.
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Affiliation(s)
- Qi Wu
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China.
| | - Hanpu Zhang
- Department of Colorectal Surgery, The First Affiliated Hospital, Zhejiang University, Hangzhou, China
| | - Si Sun
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China
| | - Lijun Wang
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China.
| | - Shengrong Sun
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China.
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13
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Goutas A, Trachana V. Stem cells' centrosomes: How can organelles identified 130 years ago contribute to the future of regenerative medicine? World J Stem Cells 2021; 13:1177-1196. [PMID: 34630857 PMCID: PMC8474719 DOI: 10.4252/wjsc.v13.i9.1177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/03/2021] [Accepted: 08/09/2021] [Indexed: 02/06/2023] Open
Abstract
At the core of regenerative medicine lies the expectation of repair or replacement of damaged tissues or whole organs. Donor scarcity and transplant rejection are major obstacles, and exactly the obstacles that stem cell-based therapy promises to overcome. These therapies demand a comprehensive understanding of the asymmetric division of stem cells, i.e. their ability to produce cells with identical potency or differentiated cells. It is believed that with better understanding, researchers will be able to direct stem cell differentiation. Here, we describe extraordinary advances in manipulating stem cell fate that show that we need to focus on the centrosome and the centrosome-derived primary cilium. This belief comes from the fact that this organelle is the vehicle that coordinates the asymmetric division of stem cells. This is supported by studies that report the significant role of the centrosome/cilium in orchestrating signaling pathways that dictate stem cell fate. We anticipate that there is sufficient evidence to place this organelle at the center of efforts that will shape the future of regenerative medicine.
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Affiliation(s)
- Andreas Goutas
- Department of Biology, Faculty of Medicine, University of Thessaly, Larisa 41500, Biopolis, Greece
| | - Varvara Trachana
- Department of Biology, Faculty of Medicine, University of Thessaly, Larisa 41500, Biopolis, Greece.
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14
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Yanardag S, Pugacheva EN. Primary Cilium Is Involved in Stem Cell Differentiation and Renewal through the Regulation of Multiple Signaling Pathways. Cells 2021; 10:1428. [PMID: 34201019 PMCID: PMC8226522 DOI: 10.3390/cells10061428] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 12/15/2022] Open
Abstract
Signaling networks guide stem cells during their lineage specification and terminal differentiation. Primary cilium, an antenna-like protrusion, directly or indirectly plays a significant role in this guidance. All stem cells characterized so far have primary cilia. They serve as entry- or check-points for various signaling events by controlling the signal transduction and stability. Thus, defects in the primary cilia formation or dynamics cause developmental and health problems, including but not limited to obesity, cardiovascular and renal anomalies, hearing and vision loss, and even cancers. In this review, we focus on the recent findings of how primary cilium controls various signaling pathways during stem cell differentiation and identify potential gaps in the field for future research.
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Affiliation(s)
- Sila Yanardag
- Department of Biochemistry, School of Medicine, West Virginia University, Morgantown, WV 26506, USA;
| | - Elena N. Pugacheva
- Department of Biochemistry, School of Medicine, West Virginia University, Morgantown, WV 26506, USA;
- West Virginia University Cancer Institute, School of Medicine, West Virginia University, Morgantown, WV 26506, USA
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15
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Voelkel-Johnson C. Sphingolipids in embryonic development, cell cycle regulation, and stemness - Implications for polyploidy in tumors. Semin Cancer Biol 2021; 81:206-219. [PMID: 33429049 DOI: 10.1016/j.semcancer.2020.12.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 12/26/2020] [Accepted: 12/30/2020] [Indexed: 12/12/2022]
Abstract
The aberrant biology of polyploid giant cancer cells (PGCC) includes dysregulation of the cell cycle, induction of stress responses, and dedifferentiation, all of which are likely accompanied by adaptations in biophysical properties and metabolic activity. Sphingolipids are the second largest class of membrane lipids and play important roles in many aspects of cell biology that are potentially relevant to polyploidy. We have recently shown that the function of the sphingolipid enzyme acid ceramidase (ASAH1) is critical for the ability of PGCC to generate progeny by depolyploidization but mechanisms by which sphingolipids contribute to polyploidy and generation of offspring with stem-like properties remain elusive. This review discusses the role of sphingolipids during embryonic development, cell cycle regulation, and stem cells in an effort to highlight parallels to polyploidy.
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Affiliation(s)
- Christina Voelkel-Johnson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA.
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16
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Tripathi P, Zhu Z, Qin H, Elsherbini A, Crivelli SM, Roush E, Wang G, Spassieva SD, Bieberich E. Palmitoylation of acetylated tubulin and association with ceramide-rich platforms is critical for ciliogenesis. J Lipid Res 2021; 62:100021. [PMID: 33380429 PMCID: PMC7903138 DOI: 10.1194/jlr.ra120001190] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/19/2020] [Accepted: 12/30/2020] [Indexed: 11/21/2022] Open
Abstract
Microtubules are polymers composed of αβ-tubulin subunits that provide structure to cells and play a crucial role in in the development and function of neuronal processes and cilia, microtubule-driven extensions of the plasma membrane that have sensory (primary cilia) or motor (motile cilia) functions. To stabilize microtubules in neuronal processes and cilia, α tubulin is modified by the posttranslational addition of an acetyl group, or acetylation. We discovered that acetylated tubulin in microtubules interacts with the membrane sphingolipid, ceramide. However, the molecular mechanism and function of this interaction are not understood. Here, we show that in human induced pluripotent stem cell–derived neurons, ceramide stabilizes microtubules, which indicates a similar function in cilia. Using proximity ligation assays, we detected complex formation of ceramide with acetylated tubulin in Chlamydomonas reinhardtii flagella and cilia of human embryonic kidney (HEK293T) cells, primary cultured mouse astrocytes, and ependymal cells. Using incorporation of palmitic azide and click chemistry–mediated addition of fluorophores, we show that a portion of acetylated tubulin is S-palmitoylated. S-palmitoylated acetylated tubulin is colocalized with ceramide-rich platforms in the ciliary membrane, and it is coimmunoprecipitated with Arl13b, a GTPase that mediates transport of proteins into cilia. Inhibition of S-palmitoylation with 2-bromo palmitic acid or inhibition of ceramide biosynthesis with fumonisin B1 reduces formation of the Arl13b-acetylated tubulin complex and its transport into cilia, concurrent with impairment of ciliogenesis. Together, these data show, for the first time, that ceramide-rich platforms mediate membrane anchoring and interaction of S-palmitoylated proteins that are critical for cilium formation, stabilization, and function.
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Affiliation(s)
- Priyanka Tripathi
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Zhihui Zhu
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Haiyan Qin
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Ahmed Elsherbini
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Simone M Crivelli
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA; Veterans Affairs Medical Center, Lexington, KY, USA
| | - Emily Roush
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Guanghu Wang
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Stefka D Spassieva
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA; Veterans Affairs Medical Center, Lexington, KY, USA.
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17
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De Lira MN, Raman SJ, Schulze A, Schneider-Schaulies S, Avota E. Neutral Sphingomyelinase-2 (NSM 2) Controls T Cell Metabolic Homeostasis and Reprogramming During Activation. Front Mol Biosci 2020; 7:217. [PMID: 33088808 PMCID: PMC7498697 DOI: 10.3389/fmolb.2020.00217] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 08/04/2020] [Indexed: 12/15/2022] Open
Abstract
Neutral sphingomyelinase-2 (NSM2) is a member of a superfamily of enzymes responsible for conversion of sphingomyelin into phosphocholine and ceramide at the cytosolic leaflet of the plasma membrane. Upon specific ablation of NSM2, T cells proved to be hyper-responsive to CD3/CD28 co-stimulation, indicating that the enzyme acts to dampen early overshooting activation of these cells. It remained unclear whether hyper-reactivity of NSM2-deficient T cells is supported by a deregulated metabolic activity in these cells. Here, we demonstrate that ablation of NSM2 activity affects metabolism of the quiescent CD4+ T cells which accumulate ATP in mitochondria and increase basal glycolytic activity. This supports enhanced production of total ATP and metabolic switch early after TCR/CD28 stimulation. Most interestingly, increased metabolic activity in resting NSM2-deficient T cells does not support sustained response upon stimulation. While elevated under steady-state conditions in NSM2-deficient CD4+ T cells, the mTORC1 pathway regulating mitochondria size, oxidative phosphorylation, and ATP production is impaired after 24 h of stimulation. Taken together, the absence of NSM2 promotes a hyperactive metabolic state in unstimulated CD4+ T cells yet fails to support sustained T cell responses upon antigenic stimulation.
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Affiliation(s)
| | | | - Almut Schulze
- Division of Tumor Metabolism and Microenvironment, German Cancer Research Center, Heidelberg, Germany
| | | | - Elita Avota
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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18
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Kaiser F, Huebecker M, Wachten D. Sphingolipids controlling ciliary and microvillar function. FEBS Lett 2020; 594:3652-3667. [PMID: 32415987 DOI: 10.1002/1873-3468.13816] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/04/2020] [Accepted: 05/10/2020] [Indexed: 12/15/2022]
Abstract
Cilia and microvilli are membrane protrusions that extend from the surface of many different mammalian cell types. Motile cilia or flagella are only found on specialized cells, where they control cell movement or the generation of fluid flow, whereas immotile primary cilia protrude from the surface of almost every mammalian cell to detect and transduce extracellular signals. Despite these differences, all cilia consist of a microtubule core called the axoneme. Microvilli instead contain bundled linear actin filaments and are mainly localized on epithelial cells, where they modulate the absorption of nutrients. Cilia and microvilli constitute subcellular compartments with distinctive lipid and protein repertoires and specialized functions. Here, we summarize the role of sphingolipids in defining the identity and controlling the function of cilia and microvilli in mammalian cells.
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Affiliation(s)
- Fabian Kaiser
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Germany
| | - Mylene Huebecker
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Germany
| | - Dagmar Wachten
- Institute of Innate Immunity, Biophysical Imaging, Medical Faculty, University of Bonn, Germany
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19
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Bieder A, Yoshihara M, Katayama S, Krjutškov K, Falk A, Kere J, Tapia-Páez I. Dyslexia Candidate Gene and Ciliary Gene Expression Dynamics During Human Neuronal Differentiation. Mol Neurobiol 2020; 57:2944-2958. [PMID: 32445086 PMCID: PMC7320047 DOI: 10.1007/s12035-020-01905-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 03/19/2020] [Indexed: 11/30/2022]
Abstract
Developmental dyslexia (DD) is a neurodevelopmental condition with complex genetic mechanisms. A number of candidate genes have been identified, some of which are linked to neuronal development and migration and to ciliary functions. However, expression and regulation of these genes in human brain development and neuronal differentiation remain uncharted. Here, we used human long-term self-renewing neuroepithelial stem (lt-NES, here termed NES) cells derived from human induced pluripotent stem cells to study neuronal differentiation in vitro. We characterized gene expression changes during differentiation by using RNA sequencing and validated dynamics for selected genes by qRT-PCR. Interestingly, we found that genes related to cilia were significantly enriched among upregulated genes during differentiation, including genes linked to ciliopathies with neurodevelopmental phenotypes. We confirmed the presence of primary cilia throughout neuronal differentiation. Focusing on dyslexia candidate genes, 33 out of 50 DD candidate genes were detected in NES cells by RNA sequencing, and seven candidate genes were upregulated during differentiation to neurons, including DYX1C1 (DNAAF4), a highly replicated DD candidate gene. Our results suggest a role of ciliary genes in differentiating neuronal cells and show that NES cells provide a relevant human neuronal model to study ciliary and DD candidate genes.
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Affiliation(s)
- Andrea Bieder
- Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden.
| | - Masahito Yoshihara
- Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden
| | - Shintaro Katayama
- Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden
| | - Kaarel Krjutškov
- Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden.,Competence Centre on Health Technologies, Tartu, Estonia.,Research Program of Molecular Neurology, Research Programs Unit, University of Helsinki, Helsinki, Finland.,Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Anna Falk
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Juha Kere
- Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden. .,Research Program of Molecular Neurology, Research Programs Unit, University of Helsinki, Helsinki, Finland. .,Folkhälsan Institute of Genetics, Helsinki, Finland. .,School of Basic and Medical Biosciences, King's College London, London, UK.
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20
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Goldsmith TM, Sakib S, Webster D, Carlson DF, Van der Hoorn F, Dobrinski I. A reduction of primary cilia but not hedgehog signaling disrupts morphogenesis in testicular organoids. Cell Tissue Res 2020; 380:191-200. [PMID: 31900662 PMCID: PMC7815324 DOI: 10.1007/s00441-019-03121-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 10/06/2019] [Indexed: 10/25/2022]
Abstract
Most mammalian cells possess a single, non-motile primary cilium that plays an important role in mediating cellular signaling pathways, such as Hedgehog (Hh) signaling. Primary cilia are present on testicular somatic cells and demonstrate a temporal expression during development; however, their role in testicular morphogenesis is not well characterized. To investigate the role of primary cilia and Hh signaling in Sertoli cells on morphogenesis, we inhibited assembly of primary cilia through CRISPR Cas9-mediated gene editing of ODF2, a structural component of primary cilia and siRNA-mediated gene silencing of IFT88, a functional component of the intraflagellar transport system. Knockdown of ODF2 and IFT88 resulted in a 50% reduction in the number of cells with primary cilia and significant shortening of the remaining cilia. The expression of GLI1, a downstream target of Hh signaling, was significantly reduced when IFT88 but not ODF2, was downregulated. When morphogenesis was examined using tubule formation in vitro and a novel testicular organoid system, loss of cilia after knockdown of both targets affected cellular assembly and organization. While the Hh pathway was found to be active during morphogenesis in vitro, addition of the Hh antagonist cyclopamine did not affect morphogenesis in either in vitro system. These results indicate that primary cilia are important for morphogenesis in vitro but Hh signaling is not the cilia-mediated pathway responsible for orchestrating morphogenic organization.
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Affiliation(s)
- Taylor M Goldsmith
- Faculty of Veterinary Medicine Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Alberta, Canada
- Cumming School of Medicine, Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N4N1, Canada
| | - Sadman Sakib
- Faculty of Veterinary Medicine Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Alberta, Canada
- Cumming School of Medicine, Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N4N1, Canada
| | - Dennis Webster
- Recombinetics Inc., 1246 University Avenue West, St. Paul, MN, 55104, USA
| | - Daniel F Carlson
- Recombinetics Inc., 1246 University Avenue West, St. Paul, MN, 55104, USA
| | - Frans Van der Hoorn
- Cumming School of Medicine, Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N4N1, Canada
| | - Ina Dobrinski
- Faculty of Veterinary Medicine Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Alberta, Canada.
- Cumming School of Medicine, Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N4N1, Canada.
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21
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Lim J, Li X, Yuan X, Yang S, Han L, Yang S. Primary cilia control cell alignment and patterning in bone development via ceramide-PKCζ-β-catenin signaling. Commun Biol 2020; 3:45. [PMID: 31988398 PMCID: PMC6985158 DOI: 10.1038/s42003-020-0767-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 12/16/2019] [Indexed: 02/01/2023] Open
Abstract
Intraflagellar transport (IFT) proteins are essential for cilia assembly and function. IFT protein mutations lead to ciliopathies, which manifest as variable skeletal abnormalities. However, how IFT proteins regulate cell alignment during bone development is unknown. Here, we show that the deletion of IFT20 in osteoblast lineage using Osterix-Cre and inducible type I Collagen-CreERT cause a compromised cell alignment and a reduced bone mass. This finding was validated by the disorganized collagen fibrils and decreased bone strength and stiffness in IFT20-deficient femurs. IFT20 maintains cilia and cell alignment in osteoblasts, as the concentric organization of three-dimensional spheroids was disrupted by IFT20 deletion. Mechanistically, IFT20 interacts with the ceramide-PKCζ complex to promote PKCζ phosphorylation in cilia and induce the apical localization of β-catenin in osteoblasts, both of which were disrupted in the absence of IFT20. These results reveal that IFT20 regulates polarity and cell alignment via ceramide-pPKCζ-β-catenin signaling during bone development.
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Affiliation(s)
- Jormay Lim
- Department of Anatomy and Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA 19104, USA
| | - Xinhua Li
- Department of Anatomy and Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA 19104, USA
| | - Xue Yuan
- Department of Oral Biology, State University of New York at Buffalo, School of Dental Medicine, Buffalo, NY, USA
| | - Shuting Yang
- Department of Anatomy and Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA 19104, USA
| | - Lin Han
- Department of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, USA
| | - Shuying Yang
- Department of Anatomy and Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA 19104, USA.
- Department of Oral Biology, State University of New York at Buffalo, School of Dental Medicine, Buffalo, NY, USA.
- The Penn Center for Musculoskeletal Disorders, University of Pennsylvania, School of Medicine, Philadelphia, PA, 19104, USA.
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22
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Natoli TA, Modur V, Ibraghimov-Beskrovnaya O. Glycosphingolipid metabolism and polycystic kidney disease. Cell Signal 2020; 69:109526. [PMID: 31911181 DOI: 10.1016/j.cellsig.2020.109526] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/02/2020] [Accepted: 01/03/2020] [Indexed: 12/21/2022]
Abstract
Sphingolipids and glycosphingolipids are classes of structurally and functionally important lipids that regulate multiple cellular processes, including membrane organization, proliferation, cell cycle regulation, apoptosis, transport, migration, and inflammatory signalling pathways. Imbalances in sphingolipid levels or subcellular localization result in dysregulated cellular processes and lead to the development and progression of multiple disorders, including polycystic kidney disease. This review will describe metabolic pathways of glycosphingolipids with a focus on the evidence linking glycosphingolipid mediated regulation of cell signalling, lipid microdomains, cilia, and polycystic kidney disease. We will discuss molecular mechanisms of glycosphingolipid dysregulation and their impact on cystogenesis. We will further highlight how modulation of sphingolipid metabolism can be translated into new approaches for the treatment of polycystic kidney disease and describe current clinical studies with glucosylceramide synthase inhibitors in Autosomal Dominant Polycystic Kidney Disease.
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Affiliation(s)
- Thomas A Natoli
- Rare and Neurological Disease Research, Sanofi-Genzyme, 49 New York Ave., Framingham, MA 01701, USA
| | - Vijay Modur
- Rare Disease Development, Sanofi-Genzyme, 50 Binney St., Cambridge, MA 02142, USA
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23
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Crivelli SM, Giovagnoni C, Visseren L, Scheithauer AL, de Wit N, den Hoedt S, Losen M, Mulder MT, Walter J, de Vries HE, Bieberich E, Martinez-Martinez P. Sphingolipids in Alzheimer's disease, how can we target them? Adv Drug Deliv Rev 2020; 159:214-231. [PMID: 31911096 DOI: 10.1016/j.addr.2019.12.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/09/2019] [Accepted: 12/31/2019] [Indexed: 01/06/2023]
Abstract
Altered levels of sphingolipids and their metabolites in the brain, and the related downstream effects on neuronal homeostasis and the immune system, provide a framework for understanding mechanisms in neurodegenerative disorders and for developing new intervention strategies. In this review we will discuss: the metabolites of sphingolipids that function as second messengers; and functional aberrations of the pathway resulting in Alzheimer's disease (AD) pathophysiology. Focusing on the central product of the sphingolipid pathway ceramide, we describ approaches to pharmacologically decrease ceramide levels in the brain and we argue on how the sphingolipid pathway may represent a new framework for developing novel intervention strategies in AD. We also highlight the possible use of clinical and non-clinical drugs to modulate the sphingolipid pathway and sphingolipid-related biological cascades.
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24
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Jiang X, Zhu Z, Qin H, Tripathi P, Zhong L, Elsherbini A, Karki S, Crivelli SM, Zhi W, Wang G, Spassieva SD, Bieberich E. Visualization of Ceramide-Associated Proteins in Ceramide-Rich Platforms Using a Cross-Linkable Ceramide Analog and Proximity Ligation Assays With Anti-ceramide Antibody. Front Cell Dev Biol 2019; 7:166. [PMID: 31475148 PMCID: PMC6706757 DOI: 10.3389/fcell.2019.00166] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 07/30/2019] [Indexed: 12/20/2022] Open
Abstract
Ceramide-rich platforms (CRPs) mediate association of proteins with the sphingolipid ceramide and may regulate protein interaction in membrane contact sites to the cytoskeleton, organelles, and infectious pathogens. However, visualization of ceramide association to proteins is one of the greatest challenges in understanding the cell biology of ceramide. Here we introduce a novel labeling technique for ceramide-associated proteins (CAPs) by combining photoactivated cross-linking of a bioorthogonal and bifunctional ceramide analog, pacFACer with proximity ligation assays (PLAs). pacFACer cross-linked to CAPs is covalently attached to a fluorophore using click chemistry. PLAs use antibodies to: (1) the candidate CAP and the fluorophore (PLA1); and (2) the CAP and ceramide (PLA2). PLA1 shows the subcellular localization of a particular CAP that is cross-linked to pacFACer, while PLA2 tests if the cross-linked CAP forms a complex with endogenous ceramide. Two proteins, tubulin and voltage-dependent anion channel 1 (VDAC1), were cross-linked to pacFACer and showed PLA signals for a complex with ceramide and pacFACer, which were predominantly colocalized with microtubules and mitochondria, respectively. Binding of tubulin and VDAC1 to ceramide was confirmed by coimmunoprecipitation assays using anti ceramide antibody. Cross-linking to pacFACer was confirmed using click chemistry-mediated attachment of biotin and streptavidin pull-down assays. Inhibition of ceramide synthases with fumonisin B1 (FB1) reduced the degree of pacFACer cross-linking and complex formation with ceramide, while it was enhanced by amyloid beta peptide (Aβ). Our results show that endogenous ceramide is critical for mediating cross-linking of CAPs to pacFACer and that a combination of cross-linking with PLAs (cross-link/PLA) is a novel tool to visualize CAPs and to understand the regulation of protein interaction with ceramide in CRPs.
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Affiliation(s)
- Xue Jiang
- Department of Rehabilitation, ShengJing Hospital of China Medical University, Shenyang, China.,Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Zhihui Zhu
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Haiyan Qin
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Priyanka Tripathi
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Liansheng Zhong
- Department of Physiology, University of Kentucky, Lexington, KY, United States.,College of Life Sciences, China Medical University, Shenyang, China
| | - Ahmed Elsherbini
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Sanjib Karki
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Simone M Crivelli
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Wenbo Zhi
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Guanghu Wang
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | | | - Erhard Bieberich
- Department of Physiology, University of Kentucky, Lexington, KY, United States
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25
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Avota E, de Lira MN, Schneider-Schaulies S. Sphingomyelin Breakdown in T Cells: Role of Membrane Compartmentalization in T Cell Signaling and Interference by a Pathogen. Front Cell Dev Biol 2019; 7:152. [PMID: 31457008 PMCID: PMC6700246 DOI: 10.3389/fcell.2019.00152] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 07/22/2019] [Indexed: 12/15/2022] Open
Abstract
Sphingolipids are major components of cellular membranes, and at steady-state level, their metabolic fluxes are tightly controlled. On challenge by external signals, they undergo rapid turnover, which substantially affects the biophysical properties of membrane lipid and protein compartments and, consequently, signaling and morphodynamics. In T cells, external cues translate into formation of membrane microdomains where proximal signaling platforms essential for metabolic reprograming and cytoskeletal reorganization are organized. This review will focus on sphingomyelinases, which mediate sphingomyelin breakdown and ensuing ceramide release that have been implicated in T-cell viability and function. Acting at the sphingomyelin pool at the extrafacial or cytosolic leaflet of cellular membranes, acid and neutral sphingomyelinases organize ceramide-enriched membrane microdomains that regulate T-cell homeostatic activity and, upon stimulation, compartmentalize receptors, membrane proximal signaling complexes, and cytoskeletal dynamics as essential for initiating T-cell motility and interaction with endothelia and antigen-presenting cells. Prominent examples to be discussed in this review include death receptor family members, integrins, CD3, and CD28 and their associated signalosomes. Progress made with regard to experimental tools has greatly aided our understanding of the role of bioactive sphingolipids in T-cell biology at a molecular level and of targets explored by a model pathogen (measles virus) to specifically interfere with their physiological activity.
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Affiliation(s)
- Elita Avota
- Institute for Virology and Immunobiology, Julius Maximilian University of Würzburg, Würzburg, Germany
| | - Maria Nathalia de Lira
- Institute for Virology and Immunobiology, Julius Maximilian University of Würzburg, Würzburg, Germany
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26
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Ross MM, Piorczynski TB, Harvey J, Burnham TS, Francis M, Larsen MW, Roe K, Hansen JM, Stark MR. Ceramide: a novel inducer for neural tube defects. Dev Dyn 2019; 248:979-996. [PMID: 31390103 DOI: 10.1002/dvdy.93] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/02/2019] [Accepted: 07/21/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Circulating plasma ceramides, a class of bioactive sphingolipids, are elevated in metabolic disorders, including obesity. Infants of women with these disorders are at 2- to 3-fold greater risk for developing a neural tube defect (NTD). This study aimed to test the effects of embryonic exposure to C2-ceramides (C2) during neural tube closure. Preliminary data shows an increase in NTDs in chick embryos after C2 exposure, and addresses potential mechanisms. RESULTS Cell and embryo models were used to examine redox shifts after ceramide exposure. While undifferentiated P19 cells were resistant to ceramide exposure, neuronally differentiated P19 cells exhibited an oxidizing shift. Consistent with these observations, GSH E h curves revealed a shift to a more oxidized state in C2 treated embryos without increasing apoptosis or changing Pax3 expression, however cell proliferation was lower. Neural tube defects were observed in 45% of chick embryos exposed to C2, compared to 12% in control embryos. CONCLUSIONS C2 exposure during critical developmental stages increased the frequency of NTDs in the avian model. Increased ROS generation in cell culture, along with the more oxidative GSH E h profiles of C2 exposed cells and embryos, support a model wherein ceramide affects neural tube closure via altered tissue redox environments.
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Affiliation(s)
- Micah M Ross
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Ted B Piorczynski
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Jamison Harvey
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Tyson S Burnham
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Morgan Francis
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Madison W Larsen
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Kyle Roe
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Jason M Hansen
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
| | - Michael R Stark
- Department of Physiology and Developmental Biology, College of Life Sciences, Brigham Young University, Provo, Utah
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27
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Collenburg L, Schneider-Schaulies S, Avota E. The neutral sphingomyelinase 2 in T cell receptor signaling and polarity. Biol Chem 2019; 399:1147-1155. [PMID: 29337691 DOI: 10.1515/hsz-2017-0280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/31/2017] [Indexed: 01/13/2023]
Abstract
By hydrolyzing its substrate sphingomyelin at the cytosolic leaflet of cellular membranes, the neutral sphingomyelinase 2 (NSM2) generates microdomains which serve as docking sites for signaling proteins and thereby, functions to regulate signal relay. This has been particularly studied in cellular stress responses while the regulatory role of this enzyme in the immune cell compartment has only recently emerged. In T cells, phenotypic polarization by co-ordinated cytoskeletal remodeling is central to motility and interaction with endothelial or antigen-presenting cells during tissue recruitment or immune synapse formation, respectively. This review highlights studies adressing the role of NSM2 in T cell polarity in which the enzyme plays a major role in regulating cytoskeletal dynamics.
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Affiliation(s)
- Lena Collenburg
- Institute for Virology and Immunobiology, University of Würzburg, Versbacher Str. 7, D-97078 Würzburg, Germany
| | - Sibylle Schneider-Schaulies
- Institute for Virology and Immunobiology, University of Würzburg, Versbacher Str. 7, D-97078 Würzburg, Germany
| | - Elita Avota
- Institute for Virology and Immunobiology, University of Würzburg, Versbacher Str. 7, D-97078 Würzburg, Germany
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28
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Wang G, Bieberich E. Sphingolipids in neurodegeneration (with focus on ceramide and S1P). Adv Biol Regul 2018; 70:51-64. [PMID: 30287225 PMCID: PMC6251739 DOI: 10.1016/j.jbior.2018.09.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 09/20/2018] [Accepted: 09/21/2018] [Indexed: 04/14/2023]
Abstract
For many decades, research on sphingolipids associated with neurodegenerative disease focused on alterations in glycosphingolipids, particularly glycosylceramides (cerebrosides), sulfatides, and gangliosides. This seemed quite natural since many of these glycolipids are constituents of myelin and accumulated in lipid storage diseases (sphingolipidoses) resulting from enzyme deficiencies in glycolipid metabolism. With the advent of recognizing ceramide and its derivative, sphingosine-1-phosphate (S1P), as key players in lipid cell signaling and regulation of cell death and survival, research focus shifted toward these two sphingolipids. Ceramide and S1P are invoked in a plethora of cell biological processes participating in neurodegeneration such as ER stress, autophagy, dysregulation of protein and lipid transport, exosome secretion and neurotoxic protein spreading, neuroinflammation, and mitochondrial dysfunction. Hence, it is timely to discuss various functions of ceramide and S1P in neurodegenerative disease and to define sphingolipid metabolism and cell signaling pathways as potential targets for therapy.
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Affiliation(s)
- Guanghu Wang
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky, Lexington, KY, USA.
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Bieberich E. Sphingolipids and lipid rafts: Novel concepts and methods of analysis. Chem Phys Lipids 2018; 216:114-131. [PMID: 30194926 PMCID: PMC6196108 DOI: 10.1016/j.chemphyslip.2018.08.003] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/20/2018] [Accepted: 08/25/2018] [Indexed: 12/12/2022]
Abstract
About twenty years ago, the functional lipid raft model of the plasma membrane was published. It took into account decades of research showing that cellular membranes are not just homogenous mixtures of lipids and proteins. Lateral anisotropy leads to assembly of membrane domains with specific lipid and protein composition regulating vesicular traffic, cell polarity, and cell signaling pathways in a plethora of biological processes. However, what appeared to be a clearly defined entity of clustered raft lipids and proteins became increasingly fluid over the years, and many of the fundamental questions about biogenesis and structure of lipid rafts remained unanswered. Experimental obstacles in visualizing lipids and their interactions hampered progress in understanding just how big rafts are, where and when they are formed, and with which proteins raft lipids interact. In recent years, we have begun to answer some of these questions and sphingolipids may take center stage in re-defining the meaning and functional significance of lipid rafts. In addition to the archetypical cholesterol-sphingomyelin raft with liquid ordered (Lo) phase and the liquid-disordered (Ld) non-raft regions of cellular membranes, a third type of microdomains termed ceramide-rich platforms (CRPs) with gel-like structure has been identified. CRPs are "ceramide rafts" that may offer some fresh view on the membrane mesostructure and answer several critical questions for our understanding of lipid rafts.
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Affiliation(s)
- Erhard Bieberich
- Department of Physiology at the University of Kentucky, Lexington, KY, United States.
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30
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Visualizing bioactive ceramides. Chem Phys Lipids 2018; 216:142-151. [PMID: 30266560 DOI: 10.1016/j.chemphyslip.2018.09.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 11/23/2022]
Abstract
In the last 30 years, ceramides have been found to mediate a myriad of biological processes. Ceramides have been recognized as bioactive molecules and their metabolizing enzymes are attractive targets in cancer therapy and other diseases. The molecular mechanism of action of cellular ceramides are still not fully established, with insights into roles through modification of lipid rafts, creation of ceramide platforms, ceramide channels, or through regulation of direct protein effectors such as protein phosphatases and kinases. Recently, the 'Many Ceramides' hypothesis focuses on distinct pools of subcellular ceramides and ceramide species as potential defined bioactive entities. Traditional methods that measure changes in ceramide levels in the whole cell, such as mass spectrometry, fluorescent ceramide analogues, and ceramide antibodies, fail to differentiate specific bioactive species at the subcellular level. However, a few ceramide binding proteins have been reported, and a smaller subgroup within these, have been shown to translocate to ceramide-enriched membranes, revealing these localized pools of bioactive ceramides. In this review we want to discuss and consolidate these works and explore the possibility of defining these binding proteins as new tools are emerging to visualize bioactive ceramides in cells. Our goal is to encourage the scientific community to explore these ceramide partners, to improve techniques to refine the list of these binding partners, making possible the identification of specific domains that recognize and bind ceramides to be used to visualize the 'Many Ceramides' in the cell.
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31
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Abstract
Exosomes are secreted extracellular vesicles (EVs) that carry micro RNAs and other factors to reprogram cancer cells and tissues affected by cancer. Exosomes are exchanged between cancer cells and other tissues, often to prepare a premetastatic niche, escape immune surveillance, or spread multidrug resistance. Only a few studies investigated the function of lipids in exosomes although their lipid composition is different from that of the secreting cells. Ceramide is one of the lipids critical for exosome formation, and it is also enriched in these EVs. New research suggests that lipids in the exosomal membrane may organize and transmit "mobile rafts" that turn exosomes into extracellular signalosomes spreading activation of cell signaling pathways in oncogenesis and metastasis. Ceramide may modulate the function of mobile rafts and their effect on these cell signaling pathways. The critical role of lipids and, in particular, ceramide for formation, secretion, and function of exosomes may lead to a radically new understanding of cancer biology and therapy.
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Affiliation(s)
- Ahmed Elsherbini
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky, Lexington, KY, United States
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32
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Activation of neutral sphingomyelinase 2 by starvation induces cell-protective autophagy via an increase in Golgi-localized ceramide. Cell Death Dis 2018; 9:670. [PMID: 29867196 PMCID: PMC5986760 DOI: 10.1038/s41419-018-0709-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/18/2018] [Accepted: 05/02/2018] [Indexed: 12/19/2022]
Abstract
Autophagy is essential for optimal cell function and survival, and the entire process accompanies membrane dynamics. Ceramides are produced by different enzymes at different cellular membrane sites and mediate differential signaling. However, it remains unclear which ceramide-producing pathways/enzymes participate in autophagy regulation under physiological conditions such as nutrient starvation, and what the underlying mechanisms are. In this study, we demonstrate that among ceramide-producing enzymes, neutral sphingomyelinase 2 (nSMase2) plays a key role in autophagy during nutrient starvation. nSMase2 was rapidly and stably activated upon starvation, and the enzymatic reaction in the Golgi apparatus facilitated autophagy through the activation of p38 MAPK and inhibition of mTOR. Moreover, nSMase2 played a protective role against cellular damage depending on autophagy. These findings suggest that nSMase2 is a novel regulator of autophagy and provide evidence that Golgi-localized ceramides participate in cytoprotective autophagy against starvation.
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33
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Makdissy N, Haddad K, AlBacha JD, Chaker D, Ismail B, Azar A, Oreibi G, Ayoub D, Achkar I, Quilliot D, Fajloun Z. Essential role of ATP6AP2 enrichment in caveolae/lipid raft microdomains for the induction of neuronal differentiation of stem cells. Stem Cell Res Ther 2018; 9:132. [PMID: 29751779 PMCID: PMC5948768 DOI: 10.1186/s13287-018-0862-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/19/2018] [Accepted: 04/04/2018] [Indexed: 01/19/2023] Open
Abstract
Background The subcellular distribution of prorenin receptor and adaptor protein ATP6AP2 may affect neurogenesis. In this study, we hypothesized that ATP6AP2 expression and subcellular relocalization from caveolae/lipid raft microdomains (CLR-Ms) to intracellular sites may correlate with neuronal differentiation (Neu-Dif) of adipose-derived mesenchymal stem cells (ADSCs). Methods Human ADSCs isolated from 24 healthy donors and 24 patients with neurological disorders (ND) were cultured and induced for Neu-Dif. The mechanism of action of ATP6AP2 and the impact of its localization within the plasma membrane (particularly CLR-Ms) and intracellular sites on several pathways (mitogen-activated protein kinase, Wnt(s) signaling and others) and intracellular calcium and exosome release were evaluated. The impact of CLR-Ms on ATP6AP2 or vice versa was determined by pharmacological disruption of CLR-Ms or siATP6AP2 assays. Results In patients with ND, loss of ATP6AP2 from CLR-Ms correlated with an inhibition of Neu-Dif and signaling. However, its relocalization in CLR-Ms was positively correlated to induction of Neu-Dif in healthy subjects. An apparent switch from canonical to noncanonical Wnt signaling as well as from caveolin to flotillin occurs concurrently with the increases of ATP6AP2 expression during neurogenesis. Stimulation by renin activates ERK/JNK/CREB/c-Jun but failed to induce β-catenin. Wnt5a enhanced the renin-induced JNK responsiveness. Gα proteins crosslink ATP6AP2 to caveolin where a switch from Gαi to Gαq is necessary for Neu-Dif. In ATP6AP2-enriched CLR-Ms, the release of exosomes was induced dependently from the intracellular Ca2+ and Gαq. Pharmacological disruption of CLR-M formation/stability impairs both ATP6AP2 localization and Neu-Dif in addition to reducing exosome release, indicating an essential role of ATP6AP2 enrichment in CLR-Ms for the induction of Neu-Dif. The mechanism is dependent on CLR-M dynamics, particularly the membrane fluidity. Knockdown of ATP6AP2 inhibited Neu-Dif but increased astrocytic-Dif, depleted ATP6AP2/flotillin/Gαq but accumulated caveolin/Gαi in CLR-Ms, and blocked the activation of JNK/ERK/c-Jun/CREB/exosome release. siATP6AP2 cells treated with sphingomyelinase/methyl-β-cyclodextrin reversed the levels of caveolin/flotillin in CLR-Ms but did not induce Neu-Dif, indicating the crucial relocalization of ATP6AP2 in CLR-Ms for neurogenesis. Treatment of ND-derived cells with nSMase showed reversibility in ATP6AP2 abundance in CLR-Ms and enhanced Neu-Dif. Conclusions This study gives evidence of the determinant role of CLR-M ATP6AP2 localization for neuronal and oligodendrocyte differentiation involving mechanisms of switches from Gαi/caveolin/canonical to Gαq/flotillin/PCP, the ERK/JNK pathway and Ca2+-dependent release of exosomes and as a potential target of drug therapy for neurodegenerative disorders. Electronic supplementary material The online version of this article (10.1186/s13287-018-0862-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nehman Makdissy
- Department of Biology, Lebanese University, Faculty of Sciences III, Kobbe, Lebanon.
| | - Katia Haddad
- Department of Biology, Lebanese University, Faculty of Sciences III, Kobbe, Lebanon
| | - Jeanne D'arc AlBacha
- Doctoral School for Sciences and Technology, Azm Center for the Research in Biotechnology and its Applications, Lebanese University, Tripoli, Lebanon
| | - Diana Chaker
- Doctoral School for Sciences and Technology, Azm Center for the Research in Biotechnology and its Applications, Lebanese University, Tripoli, Lebanon
| | - Bassel Ismail
- Doctoral School for Sciences and Technology, Faculty of Sciences I, Lebanese University, Hadath, Lebanon
| | - Albert Azar
- Reviva Regenerative Medicine Center, Human Genetic Center, Middle East Institute of Health Hospital, Bsalim, Lebanon
| | - Ghada Oreibi
- Reviva Regenerative Medicine Center, Human Genetic Center, Middle East Institute of Health Hospital, Bsalim, Lebanon
| | - David Ayoub
- Ayoub Clinic Lebanon and Department of Neuroloradiology, Limoges University Hospital, EA3842, Limoges, Lebanon
| | | | - Didier Quilliot
- Diabetologia-Endocrinology & Nutrition, CHRU Nancy, INSERM 954, University Henri Poincaré, Faculty of Medicine, Nancy, France
| | - Ziad Fajloun
- Department of Biology, Lebanese University, Faculty of Sciences III, Kobbe, Lebanon.,Doctoral School for Sciences and Technology, Azm Center for the Research in Biotechnology and its Applications, Lebanese University, Tripoli, Lebanon
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34
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Börtlein C, Draeger A, Schoenauer R, Kuhlemann A, Sauer M, Schneider-Schaulies S, Avota E. The Neutral Sphingomyelinase 2 Is Required to Polarize and Sustain T Cell Receptor Signaling. Front Immunol 2018; 9:815. [PMID: 29720981 PMCID: PMC5915489 DOI: 10.3389/fimmu.2018.00815] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/04/2018] [Indexed: 01/02/2023] Open
Abstract
By promoting ceramide release at the cytosolic membrane leaflet, the neutral sphingomyelinase 2 (NSM) is capable of organizing receptor and signalosome segregation. Its role in T cell receptor (TCR) signaling remained so far unknown. We now show that TCR-driven NSM activation is dispensable for TCR clustering and initial phosphorylation, but of crucial importance for further signal amplification. In particular, at low doses of TCR stimulatory antibodies, NSM is required for Ca2+ mobilization and T cell proliferation. NSM-deficient T cells lack sustained CD3ζ and ZAP-70 phosphorylation and are unable to polarize and stabilize their microtubular system. We identified PKCζ as the key NSM downstream effector in this second wave of TCR signaling supporting dynamics of microtubule-organizing center (MTOC). Ceramide supplementation rescued PKCζ membrane recruitment and MTOC translocation in NSM-deficient cells. These findings identify the NSM as essential in TCR signaling when dynamic cytoskeletal reorganization promotes continued lateral and vertical supply of TCR signaling components: CD3ζ, Zap70, and PKCζ, and functional immune synapses are organized and stabilized via MTOC polarization.
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Affiliation(s)
- Charlene Börtlein
- Institute for Virology and Immunobiology, University of Wuerzburg, Wuerzburg, Germany
| | - Annette Draeger
- Department of Cell Biology, Institute for Anatomy, University of Bern, Bern, Switzerland
| | - Roman Schoenauer
- Department of Cell Biology, Institute for Anatomy, University of Bern, Bern, Switzerland
| | - Alexander Kuhlemann
- Department of Biotechnology and Biophysics, University of Wuerzburg, Wuerzburg, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, University of Wuerzburg, Wuerzburg, Germany
| | | | - Elita Avota
- Institute for Virology and Immunobiology, University of Wuerzburg, Wuerzburg, Germany
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35
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Hunter M, Demarais NJ, Faull RLM, Grey AC, Curtis MA. Layer-specific lipid signatures in the human subventricular zone demonstrated by imaging mass spectrometry. Sci Rep 2018; 8:2551. [PMID: 29416059 PMCID: PMC5803191 DOI: 10.1038/s41598-018-20793-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 01/19/2018] [Indexed: 02/01/2023] Open
Abstract
The subventricular zone is a key site of adult neurogenesis and is also implicated in neurodegenerative diseases and brain cancers. In the subventricular zone, cell proliferation, migration and differentiation of nascent stem cells and neuroblasts are regulated at least in part by lipids. The human subventricular zone is distinctly layered and each layer contains discrete cell types that support the processes of neuroblast migration and neurogenesis. We set out to determine the lipid signatures of each subventricular layer in the adult human brain (n = 4). We utilised matrix-assisted laser desorption/ionisation (MALDI) imaging mass spectrometry and liquid chromatography-mass spectrometry to characterise the lipidome of the subventricular zone, with histology and microscopy used for identifying anatomical landmarks. Our findings showed that the subventricular zone was rich in sphingomyelins and phosphatidylserines but deficient in phosphatidylethanolamines. The ependymal layer had an abundance of phosphatidylinositols, whereas the myelin layer was rich in sulfatides and triglycerides. The hypocellular layer showed enrichment of sphingomyelins. No discrete lipid signature was seen in the astrocytic ribbon. The biochemical functions of these lipid classes are consistent with the localisation we observed within the SVZ. Our study may, therefore, shed new light on the role of lipids in the regulation of adult neurogenesis.
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Affiliation(s)
- Mandana Hunter
- Centre for Brain Research, University of Auckland, Auckland, 1023, New Zealand.,Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand
| | - Nicholas J Demarais
- School of Biological Sciences, Faculty of Science, University of Auckland, Auckland, 1010, New Zealand
| | - Richard L M Faull
- Centre for Brain Research, University of Auckland, Auckland, 1023, New Zealand.,Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand
| | - Angus C Grey
- Centre for Brain Research, University of Auckland, Auckland, 1023, New Zealand.,Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand
| | - Maurice A Curtis
- Centre for Brain Research, University of Auckland, Auckland, 1023, New Zealand. .,Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand.
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36
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Kong JN, Zhu Z, Itokazu Y, Wang G, Dinkins MB, Zhong L, Lin HP, Elsherbini A, Leanhart S, Jiang X, Qin H, Zhi W, Spassieva SD, Bieberich E. Novel function of ceramide for regulation of mitochondrial ATP release in astrocytes. J Lipid Res 2018; 59:488-506. [PMID: 29321137 DOI: 10.1194/jlr.m081877] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/08/2018] [Indexed: 12/14/2022] Open
Abstract
We reported that amyloid β peptide (Aβ42) activated neutral SMase 2 (nSMase2), thereby increasing the concentration of the sphingolipid ceramide in astrocytes. Here, we show that Aβ42 induced mitochondrial fragmentation in wild-type astrocytes, but not in nSMase2-deficient cells or astrocytes treated with fumonisin B1 (FB1), an inhibitor of ceramide synthases. Unexpectedly, ceramide depletion was concurrent with rapid movements of mitochondria, indicating an unknown function of ceramide for mitochondria. Using immunocytochemistry and super-resolution microscopy, we detected ceramide-enriched and mitochondria-associated membranes (CEMAMs) that were codistributed with microtubules. Interaction of ceramide with tubulin was confirmed by cross-linking to N-[9-(3-pent-4-ynyl-3-H-diazirine-3-yl)-nonanoyl]-D-erythro-sphingosine (pacFACer), a bifunctional ceramide analog, and binding of tubulin to ceramide-linked agarose beads. Ceramide-associated tubulin (CAT) translocated from the perinuclear region to peripheral CEMAMs and mitochondria, which was prevented in nSMase2-deficient or FB1-treated astrocytes. Proximity ligation and coimmunoprecipitation assays showed that ceramide depletion reduced association of tubulin with voltage-dependent anion channel 1 (VDAC1), an interaction known to block mitochondrial ADP/ATP transport. Ceramide-depleted astrocytes contained higher levels of ATP, suggesting that ceramide-induced CAT formation leads to VDAC1 closure, thereby reducing mitochondrial ATP release, and potentially motility and resistance to Aβ42 Our data also indicate that inhibiting ceramide generation may protect mitochondria in Alzheimer's disease.
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Affiliation(s)
- Ji-Na Kong
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA
| | - Zhihui Zhu
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Physiology, University of Kentucky, Lexington, KY
| | - Yutaka Itokazu
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA
| | - Guanghu Wang
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Physiology, University of Kentucky, Lexington, KY
| | - Michael B Dinkins
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA
| | - Liansheng Zhong
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Physiology, University of Kentucky, Lexington, KY.,College of Basic Medicine, China Medical University, Shenyang, People's Republic of China
| | - Hsuan-Pei Lin
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Physiology, University of Kentucky, Lexington, KY
| | - Ahmed Elsherbini
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA.,Department of Physiology, University of Kentucky, Lexington, KY
| | - Silvia Leanhart
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA
| | - Xue Jiang
- Department of Physiology, University of Kentucky, Lexington, KY.,Rehabilitation Center, ShengJing Hospital of China Medical University, Shenyang, People's Republic of China
| | - Haiyan Qin
- Department of Physiology, University of Kentucky, Lexington, KY
| | - Wenbo Zhi
- Center of Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta University, Augusta, GA
| | | | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine Augusta University, Augusta, GA .,Department of Physiology, University of Kentucky, Lexington, KY
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37
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Wang G, Spassieva SD, Bieberich E. Ceramide and S1P Signaling in Embryonic Stem Cell Differentiation. Methods Mol Biol 2018; 1697:153-171. [PMID: 28540559 PMCID: PMC5815858 DOI: 10.1007/7651_2017_43] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Bioactive sphingolipids are important regulators for stem cell survival and differentiation. Most recently, we have coined the term "morphogenetic lipids" for sphingolipids that regulate stem cells during embryonic and postnatal development. The sphingolipid ceramide and its derivative, sphingosine-1-phosphate (S1P), can act synergistically as well as antagonistically on embryonic stem (ES) cell differentiation. We show here simple as well as state-of-the-art methods to analyze sphingolipids in differentiating ES cells and discuss new protocols to use ceramide and S1P analogs for the guided differentiation of mouse ES cells toward neuronal and glial lineage.
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Affiliation(s)
- Guanghu Wang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Stefka D Spassieva
- Department of Molecular and Cellular Medicine, Texas A&M Medical Health Sciences Center, Bryan, TX, USA
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA.
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, 1120 15th Street Room CA4012, Augusta, GA, 30912, USA.
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Spassieva S, Bieberich E. Lysosphingolipids and sphingolipidoses: Psychosine in Krabbe's disease. J Neurosci Res 2017; 94:974-81. [PMID: 27638582 DOI: 10.1002/jnr.23888] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 12/14/2022]
Abstract
Until recently, lipids were considered inert building blocks of cellular membranes. This changed three decades ago when lipids were found to regulate cell polarity and vesicle transport, and the "lipid raft" concept took shape. The lipid-driven membrane anisotropy in form of "rafts" that associate with proteins led to the view that organized complexes of lipids and proteins regulate various cell functions. Disturbance of this organization can lead to cellular, tissue, and organ malfunction. Sphingolipidoses, lysosomal storage diseases that are caused by enzyme deficiencies in the sphingolipid degradation pathway, were found to be particularly detrimental to the brain. These enzyme deficiencies result in accumulation of sphingolipid metabolites in lysosomes, although it is not yet clear how this accumulation affects the organization of lipids in cellular membranes. Krabbe's disease (KD), or globoid cell leukodystrophy, was one of the first sphingolipidosis for which the raft concept offered a potential mechanism. KD is caused by mutations in the enzyme β-galactocerebrosidase; however, elevation of its substrate, galactosylceramide, is not observed or considered detrimental. Instead, it was found that a byproduct of galactosylceramide metabolism, the lysosphingolipid psychosine, is accumulated. The "psychosine hypothesis" has been refined by showing that psychosine disrupts lipid rafts and vesicular transport critical for the function of glia and neurons. The role of psychosine in KD is an example of how the disruption of sphingolipid metabolism can lead to elevation of a toxic lysosphingolipid, resulting in disruption of cellular membrane organization and neurotoxicity. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Stefka Spassieva
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, Texas
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, Geogia.
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Collenburg L, Beyersdorf N, Wiese T, Arenz C, Saied EM, Becker-Flegler KA, Schneider-Schaulies S, Avota E. The Activity of the Neutral Sphingomyelinase Is Important in T Cell Recruitment and Directional Migration. Front Immunol 2017; 8:1007. [PMID: 28871263 PMCID: PMC5566967 DOI: 10.3389/fimmu.2017.01007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 08/07/2017] [Indexed: 01/13/2023] Open
Abstract
Breakdown of sphingomyelin as catalyzed by the activity of sphingomyelinases profoundly affects biophysical properties of cellular membranes which is particularly important with regard to compartmentalization of surface receptors and their signaling relay. As it is activated both upon TCR ligation and co-stimulation in a spatiotemporally controlled manner, the neutral sphingomyelinase (NSM) has proven to be important in T cell activation, where it appears to play a particularly important role in cytoskeletal reorganization and cell polarization. Because these are important parameters in directional T cell migration and motility in tissues, we analyzed the role of the NSM in these processes. Pharmacological inhibition of NSM interfered with early lymph node homing of T cells in vivo indicating that the enzyme impacts on endothelial adhesion, transendothelial migration, sensing of chemokine gradients or, at a cellular level, acquisition of a polarized phenotype. NSM inhibition reduced adhesion of T cells to TNF-α/IFN-γ activated, but not resting endothelial cells, most likely via inhibiting high-affinity LFA-1 clustering. NSM activity proved to be highly important in directional T cell motility in response to SDF1-α, indicating that their ability to sense and translate chemokine gradients might be NSM dependent. In fact, pharmacological or genetic NSM ablation interfered with T cell polarization both at an overall morphological level and redistribution of CXCR4 and pERM proteins on endothelial cells or fibronectin, as well as with F-actin polymerization in response to SDF1-α stimulation, indicating that efficient directional perception and signaling relay depend on NSM activity. Altogether, these data support a central role of the NSM in T cell recruitment and migration both under homeostatic and inflamed conditions by regulating polarized redistribution of receptors and their coupling to the cytoskeleton.
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Affiliation(s)
- Lena Collenburg
- Institute for Virology and Immunobiology, University of Würzburg, Wuerzburg, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Wuerzburg, Germany
| | - Teresa Wiese
- Institute for Virology and Immunobiology, University of Würzburg, Wuerzburg, Germany
| | - Christoph Arenz
- Institute for Organic and Bioorganic Chemistry, Humboldt University of Berlin, Berlin, Germany
| | - Essa M Saied
- Institute for Organic and Bioorganic Chemistry, Humboldt University of Berlin, Berlin, Germany.,Chemistry Department, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | | | | | - Elita Avota
- Institute for Virology and Immunobiology, University of Würzburg, Wuerzburg, Germany
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40
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Pescio LG, Santacreu BJ, Lopez VG, Paván CH, Romero DJ, Favale NO, Sterin-Speziale NB. Changes in ceramide metabolism are essential in Madin-Darby canine kidney cell differentiation. J Lipid Res 2017; 58:1428-1438. [PMID: 28515139 DOI: 10.1194/jlr.m076349] [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: 03/21/2017] [Revised: 05/16/2017] [Indexed: 01/03/2023] Open
Abstract
Ceramides (Cers) and complex sphingolipids with defined acyl chain lengths play important roles in numerous cell processes. Six Cer synthase (CerS) isoenzymes (CerS1-6) are the key enzymes responsible for the production of the diversity of molecular species. In this study, we investigated the changes in sphingolipid metabolism during the differentiation of Madin-Darby canine kidney (MDCK) cells. By MALDI TOF TOF MS, we analyzed the molecular species of Cer, glucosylceramide (GlcCer), lactosylceramide (LacCer), and SM in nondifferentiated and differentiated cells (cultured under hypertonicity). The molecular species detected were the same, but cells subjected to hypertonicity presented higher levels of C24:1 Cer, C24:1 GlcCer, C24:1 SM, and C16:0 LacCer. Consistently with the molecular species, MDCK cells expressed CerS2, CerS4, and CerS6, but with no differences during cell differentiation. We next evaluated the different synthesis pathways with sphingolipid inhibitors and found that cells subjected to hypertonicity in the presence of amitriptyline, an inhibitor of acid sphingomyelinase, showed decreased radiolabeled incorporation in LacCer and cells did not develop a mature apical membrane. These results suggest that hypertonicity induces the endolysosomal degradation of SM, generating the Cer used as substrate for the synthesis of specific molecular species of glycosphingolipids that are essential for MDCK cell differentiation.
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Affiliation(s)
- Lucila Gisele Pescio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Bruno Jaime Santacreu
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Vanina Gisela Lopez
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina
| | - Carlos Humberto Paván
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina
| | - Daniela Judith Romero
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina
| | - Nicolás Octavio Favale
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Norma Beatriz Sterin-Speziale
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina.
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41
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Garcia-Gil M, Pierucci F, Vestri A, Meacci E. Crosstalk between sphingolipids and vitamin D3: potential role in the nervous system. Br J Pharmacol 2017; 174:605-627. [PMID: 28127747 DOI: 10.1111/bph.13726] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/16/2016] [Accepted: 01/18/2017] [Indexed: 12/14/2022] Open
Abstract
Sphingolipids are both structural and bioactive compounds. In particular, ceramide and sphingosine 1-phosphate regulate cell fate, inflammation and excitability. 1-α,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ) is known to play an important physiological role in growth and differentiation in a variety of cell types, including neural cells, through genomic actions mediated by its specific receptor, and non-genomic effects that result in the activation of specific signalling pathways. 1,25(OH)2 D3 and sphingolipids, in particular sphingosine 1-phosphate, share many common effectors, including calcium regulation, growth factors and inflammatory cytokines, but it is still not known whether they can act synergistically. Alterations in the signalling and concentrations of sphingolipids and 1,25(OH)2 D3 have been found in neurodegenerative diseases and fingolimod, a structural analogue of sphingosine, has been approved for the treatment of multiple sclerosis. This review, after a brief description of the role of sphingolipids and 1,25(OH)2 D3 , will focus on the potential crosstalk between sphingolipids and 1,25(OH)2 D3 in neural cells.
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Affiliation(s)
- Mercedes Garcia-Gil
- Department of Biology, University of Pisa, Pisa, Italy.,Interdepartmental Research Center Nutrafood 'Nutraceuticals and Food for Health', University of Pisa, Pisa, Italy
| | - Federica Pierucci
- Department of Experimental and Clinical Biomedical Sciences 'Mario Serio', Molecular and Applied Biology Research Unit, University of Florence, Florence, Italy.,Interuniversitary Miology Institutes, Italy
| | - Ambra Vestri
- Department of Experimental and Clinical Biomedical Sciences 'Mario Serio', Molecular and Applied Biology Research Unit, University of Florence, Florence, Italy.,Interuniversitary Miology Institutes, Italy
| | - Elisabetta Meacci
- Department of Experimental and Clinical Biomedical Sciences 'Mario Serio', Molecular and Applied Biology Research Unit, University of Florence, Florence, Italy.,Interuniversitary Miology Institutes, Italy
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Lyu R, Zhou J. The Multifaceted Roles of Primary Cilia in the Regulation of Stem Cell Properties and Functions. J Cell Physiol 2016; 232:935-938. [PMID: 27861880 DOI: 10.1002/jcp.25683] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 12/13/2022]
Abstract
Stem cells are a unique class of cells that are capable of self-renewal and differentiation into multiple lineages. An increasing number of studies have suggested that both embryonic and adult stem cells possess primary cilia, antenna-like structures protruding from cell surfaces that are critical for sensing and transducing environmental cues. The primary cilium appears to regulate stem cells in multiple aspects, such as lineage specification and stemness maintenance. Understanding the role of primary cilia in the control of stem cell behavior could lead to the identification of new targets for regenerative therapies. Here, we discuss recent studies investigating the diverse roles of primary cilia in the regulation of stem cell properties and functions. We also propose potential new avenues for exploration in this promising field. J. Cell. Physiol. 232: 935-938, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Rui Lyu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Jun Zhou
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of the Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China.,Institute of Biomedical Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
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44
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Protective responses to sublytic complement in the retinal pigment epithelium. Proc Natl Acad Sci U S A 2016; 113:8789-94. [PMID: 27432952 DOI: 10.1073/pnas.1523061113] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The retinal pigment epithelium (RPE) is a key site of injury in inherited and age-related macular degenerations. Abnormal activation of the complement system is a feature of these blinding diseases, yet how the RPE combats complement attack is poorly understood. The complement cascade terminates in the cell-surface assembly of membrane attack complexes (MACs), which promote inflammation by causing aberrant signal transduction. Here, we investigated mechanisms crucial for limiting MAC assembly and preserving cellular integrity in the RPE and asked how these are compromised in models of macular degeneration. Using polarized primary RPE and the pigmented Abca4(-/-) Stargardt disease mouse model, we provide evidence for two protective responses occurring within minutes of complement attack, which are essential for maintaining mitochondrial health in the RPE. First, accelerated recycling of the membrane-bound complement regulator CD59 to the RPE cell surface inhibits MAC formation. Second, fusion of lysosomes with the RPE plasma membrane immediately after complement attack limits sustained elevations in intracellular calcium and prevents mitochondrial injury. Cholesterol accumulation in the RPE, induced by vitamin A dimers or oxidized LDL, inhibits these defense mechanisms by activating acid sphingomyelinase (ASMase), which increases tubulin acetylation and derails organelle traffic. Defective CD59 recycling and lysosome exocytosis after complement attack lead to mitochondrial fragmentation and oxidative stress in the RPE. Drugs that stimulate cholesterol efflux or inhibit ASMase restore both these critical safeguards in the RPE and avert complement-induced mitochondrial injury in vitro and in Abca4(-/-) mice, indicating that they could be effective therapeutic approaches for macular degenerations.
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45
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Bodle JC, Loboa EG. Concise Review: Primary Cilia: Control Centers for Stem Cell Lineage Specification and Potential Targets for Cell-Based Therapies. Stem Cells 2016; 34:1445-54. [PMID: 26866419 DOI: 10.1002/stem.2341] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 08/07/2015] [Indexed: 01/08/2023]
Abstract
Directing stem cell lineage commitment prevails as the holy grail of translational stem cell research, particularly to those interested in the application of mesenchymal stem cells and adipose-derived stem cells in tissue engineering. However, elucidating the mechanisms underlying their phenotypic specification persists as an active area of research. In recent studies, the primary cilium structure has been intimately associated with defining cell phenotype, maintaining stemness, as well as functioning in a chemo, electro, and mechanosensory capacity in progenitor and committed cell types. Many hypothesize that the primary cilium may indeed be another important player in defining and controlling cell phenotype, concomitant with lineage-dictated cytoskeletal dynamics. Many of the studies on the primary cilium have emerged from disparate areas of biological research, and crosstalk amongst these areas of research is just beginning. To date, there has not been a thorough review of how primary cilia fit into the current paradigm of stem cell differentiation and this review aims to summarize the current cilia work in this context. The goal of this review is to highlight the cilium's function and integrate this knowledge into the working knowledge of stem cell biologists and tissue engineers developing regenerative medicine technologies. Stem Cells 2016;34:1445-1454.
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Affiliation(s)
- Josephine C Bodle
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill and North Carolina State University, Raleigh, North Carolina, USA
| | - Elizabeth G Loboa
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill and North Carolina State University, Raleigh, North Carolina, USA.,College of Engineering University of Missouri, Columbia Columbia, Missouri, USA
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46
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Li L, Yang XJ. Tubulin acetylation: responsible enzymes, biological functions and human diseases. Cell Mol Life Sci 2015; 72:4237-55. [PMID: 26227334 PMCID: PMC11113413 DOI: 10.1007/s00018-015-2000-5] [Citation(s) in RCA: 178] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 12/28/2022]
Abstract
Microtubules have important functions ranging from maintenance of cell morphology to subcellular transport, cellular signaling, cell migration, and formation of cell polarity. At the organismal level, microtubules are crucial for various biological processes, such as viral entry, inflammation, immunity, learning and memory in mammals. Microtubules are subject to various covalent modifications. One such modification is tubulin acetylation, which is associated with stable microtubules and conserved from protists to humans. In the past three decades, this reversible modification has been studied extensively. In mammals, its level is mainly governed by opposing actions of α-tubulin acetyltransferase 1 (ATAT1) and histone deacetylase 6 (HDAC6). Knockout studies of the mouse enzymes have yielded new insights into biological functions of tubulin acetylation. Abnormal levels of this modification are linked to neurological disorders, cancer, heart diseases and other pathological conditions, thereby yielding important therapeutic implications. This review summarizes related studies and concludes that tubulin acetylation is important for regulating microtubule architecture and maintaining microtubule integrity. Together with detyrosination, glutamylation and other modifications, tubulin acetylation may form a unique 'language' to regulate microtubule structure and function.
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Affiliation(s)
- Lin Li
- Rosalind and Morris Goodman Cancer Research Center, Montreal, QC, H3A 1A3, Canada
- Department of Medicine, Montreal, QC, H3A 1A3, Canada
| | - Xiang-Jiao Yang
- Rosalind and Morris Goodman Cancer Research Center, Montreal, QC, H3A 1A3, Canada.
- Department of Medicine, Montreal, QC, H3A 1A3, Canada.
- Department of Biochemistry, McGill University, Montreal, QC, H3A 1A3, Canada.
- McGill University Health Center, Montreal, QC, H3A 1A3, Canada.
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Kong JN, Hardin K, Dinkins M, Wang G, He Q, Mujadzic T, Zhu G, Bielawski J, Spassieva S, Bieberich E. Regulation of Chlamydomonas flagella and ependymal cell motile cilia by ceramide-mediated translocation of GSK3. Mol Biol Cell 2015; 26:4451-65. [PMID: 26446842 PMCID: PMC4666139 DOI: 10.1091/mbc.e15-06-0371] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 09/30/2015] [Indexed: 12/23/2022] Open
Abstract
Cilia are important organelles formed by cell membrane protrusions; however, little is known about their regulation by membrane lipids. A novel, evolutionarily conserved activation mechanism for GSK3 by the sphingolipid (phyto)ceramide is characterized that is critical for ciliogenesis in Chlamydomonas and murine ependymal cells. Cilia are important organelles formed by cell membrane protrusions; however, little is known about their regulation by membrane lipids. We characterize a novel activation mechanism for glycogen synthase kinase-3 (GSK3) by the sphingolipids phytoceramide and ceramide that is critical for ciliogenesis in Chlamydomonas and murine ependymal cells, respectively. We show for the first time that Chlamydomonas expresses serine palmitoyl transferase (SPT), the first enzyme in (phyto)ceramide biosynthesis. Inhibition of SPT in Chlamydomonas by myriocin led to loss of flagella and reduced tubulin acetylation, which was prevented by supplementation with the precursor dihydrosphingosine. Immunocytochemistry showed that (phyto)ceramide was colocalized with phospho–Tyr-216-GSK3 (pYGSK3) at the base and tip of Chlamydomonas flagella and motile cilia in ependymal cells. The (phyto)ceramide distribution was consistent with that of a bifunctional ceramide analogue UV cross-linked and visualized by click-chemistry–mediated fluorescent labeling. Ceramide depletion, by myriocin or neutral sphingomyelinase deficiency (fro/fro mouse), led to GSK3 dephosphorylation and defective flagella and cilia. Motile cilia were rescued and pYGSK3 localization restored by incubation of fro/fro ependymal cells with exogenous C24:1 ceramide, which directly bound to pYGSK3. Our findings suggest that (phyto)ceramide-mediated translocation of pYGSK into flagella and cilia is an evolutionarily conserved mechanism fundamental to the regulation of ciliogenesis.
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Affiliation(s)
- Ji Na Kong
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Kara Hardin
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Michael Dinkins
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Guanghu Wang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Qian He
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Tarik Mujadzic
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Gu Zhu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Jacek Bielawski
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425
| | - Stefka Spassieva
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425
| | - Erhard Bieberich
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
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Ran J, Yang Y, Li D, Liu M, Zhou J. Deacetylation of α-tubulin and cortactin is required for HDAC6 to trigger ciliary disassembly. Sci Rep 2015; 5:12917. [PMID: 26246421 PMCID: PMC4526867 DOI: 10.1038/srep12917] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 07/14/2015] [Indexed: 12/21/2022] Open
Abstract
Cilia play important roles in sensing extracellular signals and directing fluid flow. Ciliary dysfunction is associated with a variety of diseases known as ciliopathies. Histone deacetylase 6 (HDAC6) has recently emerged as a major driver of ciliary disassembly, but little is known about the downstream players. Here we provide the first evidence that HDAC6-mediated deacetylation of α-tubulin and cortactin is critical for its induction of ciliary disassembly. HDAC6 is localized in the cytoplasm and enriched at the centrosome and basal body. Overexpression of HDAC6 decreases the levels of acetylated α-tubulin and cortactin without affecting the expression or localization of known ciliary regulators. We also find that overexpression of α-tubulin or cortactin or their acetylation-deficient mutants enhances the ability of HDAC6 to induce ciliary disassembly. In addition, acetylation-mimicking mutants of α-tubulin and cortactin counteract HDAC6-induced ciliary disassembly. Furthermore, HDAC6 stimulates actin polymerization, and inhibition of actin polymerization abolishes the activity of HDAC6 to trigger ciliary disassembly. These findings provide mechanistic insight into the ciliary role of HDAC6 and underscore the importance of reversible acetylation in regulating ciliary homeostasis.
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Affiliation(s)
- Jie Ran
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yunfan Yang
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Dengwen Li
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Min Liu
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jun Zhou
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
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49
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Ong WY, Herr DR, Farooqui T, Ling EA, Farooqui AA. Role of sphingomyelinases in neurological disorders. Expert Opin Ther Targets 2015; 19:1725-42. [DOI: 10.1517/14728222.2015.1071794] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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50
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Whitfield JF, Chiarini A, Dal Prà I, Armato U, Chakravarthy B. The Possible Roles of the Dentate Granule Cell's Leptin and Other Ciliary Receptors in Alzheimer's Neuropathology. Cells 2015; 4:253-74. [PMID: 26184316 PMCID: PMC4588035 DOI: 10.3390/cells4030253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 06/18/2015] [Accepted: 07/06/2015] [Indexed: 12/20/2022] Open
Abstract
Dentate-gyral granule cells in the hippocampus plus dentate gyrus memory-recording/retrieving machine, unlike most other neurons in the brain, are continuously being generated in the adult brain with the important task of separating overlapping patterns of data streaming in from the outside world via the entorhinal cortex. This "adult neurogenesis" is driven by tools in the mature granule cell's cilium. Here we report our discovery of leptin's LepRb receptor in this cilium. In addition, we discuss how ciliary LepRb signaling might be involved with ciliary p75NTR and SSTR3 receptors in adult neurogenesis and memory formation as well as attenuation of Alzheimer's neuropathology by reducing the production of its toxic amyloid-β-derived drivers.
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Affiliation(s)
- James F Whitfield
- Human Health Therapeutics, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada.
| | - Anna Chiarini
- Histology & Embryology Unit, Department of Life & Reproduction Sciences, University of Verona Medical School, 8 Strada Le Grazie, Verona, Venetia 37134, Italy.
| | - Ilaria Dal Prà
- Histology & Embryology Unit, Department of Life & Reproduction Sciences, University of Verona Medical School, 8 Strada Le Grazie, Verona, Venetia 37134, Italy.
| | - Ubaldo Armato
- Histology & Embryology Unit, Department of Life & Reproduction Sciences, University of Verona Medical School, 8 Strada Le Grazie, Verona, Venetia 37134, Italy.
| | - Balu Chakravarthy
- Human Health Therapeutics, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada.
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