1
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Zhong BH, Dong M. The implication of ciliary signaling pathways for epithelial-mesenchymal transition. Mol Cell Biochem 2024; 479:1535-1543. [PMID: 37490178 PMCID: PMC11224103 DOI: 10.1007/s11010-023-04817-w] [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: 05/04/2023] [Accepted: 07/15/2023] [Indexed: 07/26/2023]
Abstract
Epithelial-to-mesenchymal transition (EMT), which plays an essential role in development, tissue repair and fibrosis, and cancer progression, is a reversible cellular program that converts epithelial cells to mesenchymal cell states characterized by motility-invasive properties. The mostly signaling pathways that initiated and controlled the EMT program are regulated by a solitary, non-motile organelle named primary cilium. Acting as a signaling nexus, primary cilium dynamically concentrates signaling molecules to respond to extracellular cues. Recent research has provided direct evidence of connection between EMT and primary ciliogenesis in multiple contexts, but the mechanistic understanding of this relationship is complicated and still undergoing. In this review, we describe the current knowledge about the ciliary signaling pathways involved in EMT and list the direct evidence that shows the link between them, trying to figure out the intricate relationship between EMT and primary ciliogenesis, which may aid the future development of primary cilium as a novel therapeutic approach targeted to EMT.
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Affiliation(s)
- Bang-Hua Zhong
- Department of Gastrointestinal Surgery, The First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Ming Dong
- Department of Gastrointestinal Surgery, The First Hospital of China Medical University, Shenyang, Liaoning, China.
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2
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Horwitz A, Levi-Carmel N, Shnaider O, Birk R. BBS genes are involved in accelerated proliferation and early differentiation of BBS-related tissues. Differentiation 2024; 135:100745. [PMID: 38215537 DOI: 10.1016/j.diff.2024.100745] [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: 09/06/2023] [Revised: 01/01/2024] [Accepted: 01/02/2024] [Indexed: 01/14/2024]
Abstract
Bardet-Biedl syndrome (BBS) is an inherited disorder primarily ciliopathy with pleiotropic multi-systemic phenotypic involvement, including adipose, nerve, retinal, kidney, Etc. Consequently, it is characterized by obesity, cognitive impairment and retinal, kidney and cutaneous abnormalities. Initial studies, including ours have shown that BBS genes play a role in the early developmental stages of adipocytes and β-cells. However, this role in other BBS-related tissues is unknown. We investigated BBS genes involvement in the proliferation and early differentiation of different BBS cell types. The involvement of BBS genes in cellular proliferation were studied in seven in-vitro and transgenic cell models; keratinocytes (hHaCaT) and Ras-transfected keratinocytes (Ras-hHaCaT), neuronal cell lines (hSH-SY5Y and rPC-12), silenced BBS4 neural cell lines (siBbs4 hSH-SY5Y and siBbs4 rPC-12), adipocytes (m3T3L1), and ex-vivo transformed B-cells obtain from BBS4 patients, using molecular and biochemical methodologies. RashHaCaT cells showed an accelerated proliferation rate in parallel to significant reduction in the transcript levels of BBS1, 2, and 4. BBS1, 2, and 4 transcripts linked with hHaCaT cell cycle arrest (G1 phase) using both chemical (CDK4 inhibitor) and serum deprivation methodologies. Adipocyte (m3T3-L1) Bbs1, 2 and 4 transcript levels corresponded to the cell cycle phase (CDK4 inhibitor and serum deprivation). SiBBS4 hSH-SY5Y cells exhibited early cell proliferation and differentiation (wound healing assay) rates. SiBbs4 rPC-12 models exhibited significant proliferation and differentiation rate corresponding to Nestin expression levels. BBS4 patients-transformed B-cells exhibited an accelerated proliferation rate (LPS-induced methodology). In conclusions, the BBS4 gene plays a significant, similar and global role in the cellular proliferation of various BBS related tissues. These results highlight the universal role of the BBS gene in the cell cycle, and further deepen the knowledge of the mechanisms underlying the development of BBS.
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Affiliation(s)
- Avital Horwitz
- Nutrition Department, Health Sciences Faculty, Ariel University, Israel
| | | | - Olga Shnaider
- Nutrition Department, Health Sciences Faculty, Ariel University, Israel
| | - Ruth Birk
- Nutrition Department, Health Sciences Faculty, Ariel University, Israel.
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3
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Saito M, Otsu W, Miyadera K, Nishimura Y. Recent advances in the understanding of cilia mechanisms and their applications as therapeutic targets. Front Mol Biosci 2023; 10:1232188. [PMID: 37780208 PMCID: PMC10538646 DOI: 10.3389/fmolb.2023.1232188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/24/2023] [Indexed: 10/03/2023] Open
Abstract
The primary cilium is a single immotile microtubule-based organelle that protrudes into the extracellular space. Malformations and dysfunctions of the cilia have been associated with various forms of syndromic and non-syndromic diseases, termed ciliopathies. The primary cilium is therefore gaining attention due to its potential as a therapeutic target. In this review, we examine ciliary receptors, ciliogenesis, and ciliary trafficking as possible therapeutic targets. We first discuss the mechanisms of selective distribution, signal transduction, and physiological roles of ciliary receptors. Next, pathways that regulate ciliogenesis, specifically the Aurora A kinase, mammalian target of rapamycin, and ubiquitin-proteasome pathways are examined as therapeutic targets to regulate ciliogenesis. Then, in the photoreceptors, the mechanism of ciliary trafficking which takes place at the transition zone involving the ciliary membrane proteins is reviewed. Finally, some of the current therapeutic advancements highlighting the role of large animal models of photoreceptor ciliopathy are discussed.
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Affiliation(s)
- Masaki Saito
- Department of Molecular Physiology and Pathology, School of Pharma-Sciences, Teikyo University, Tokyo, Japan
| | - Wataru Otsu
- Department of Biomedical Research Laboratory, Gifu Pharmaceutical University, Gifu, Japan
| | - Keiko Miyadera
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Yuhei Nishimura
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
- Mie University Research Center for Cilia and Diseases, Tsu, Mie, Japan
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4
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Lucarelli M, Camuso S, Di Pietro C, Bruno F, La Rosa P, Marazziti D, Fiorenza MT, Canterini S. Reduced Cerebellar BDNF Availability Affects Postnatal Differentiation and Maturation of Granule Cells in a Mouse Model of Cholesterol Dyshomeostasis. Mol Neurobiol 2023; 60:5395-5410. [PMID: 37314654 PMCID: PMC10415459 DOI: 10.1007/s12035-023-03435-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 06/06/2023] [Indexed: 06/15/2023]
Abstract
Niemann-Pick type C1 (NPC1) disease is a lysosomal lipid storage disorder due to mutations in the NPC1 gene resulting in the accumulation of cholesterol within the endosomal/lysosomal compartments. The prominent feature of the disorder is the progressive Purkinje cell degeneration leading to ataxia.In a mouse model of NPC1 disease, we have previously demonstrated that impaired Sonic hedgehog signaling causes defective proliferation of granule cells (GCs) and abnormal cerebellar morphogenesis. Studies conducted on cortical and hippocampal neurons indicate a functional interaction between Sonic hedgehog and brain-derived neurotrophic factor (BDNF) expression, leading us to hypothesize that BDNF signaling may be altered in Npc1 mutant mice, contributing to the onset of cerebellar alterations present in NPC1 disease before the appearance of signs of ataxia.We characterized the expression/localization patterns of the BDNF and its receptor, tropomyosin-related kinase B (TrkB), in the early postnatal and young adult cerebellum of the Npc1nmf164 mutant mouse strain.In Npc1nmf164 mice, our results show (i) a reduced expression of cerebellar BDNF and pTrkB in the first 2 weeks postpartum, phases in which most GCs complete the proliferative/migrative program and begin differentiation; (ii) an altered subcellular localization of the pTrkB receptor in GCs, both in vivo and in vitro; (iii) reduced chemotactic response to BDNF in GCs cultured in vitro, associated with impaired internalization of the activated TrkB receptor; (iv) an overall increase in dendritic branching in mature GCs, resulting in impaired differentiation of the cerebellar glomeruli, the major synaptic complex between GCs and mossy fibers.
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Affiliation(s)
- Micaela Lucarelli
- Division of Neuroscience, Dept. of Psychology, University La Sapienza, Rome, Italy
- PhD Program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Serena Camuso
- Division of Neuroscience, Dept. of Psychology, University La Sapienza, Rome, Italy
- PhD Program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Chiara Di Pietro
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), I-00015, Monterotondo Scalo, Italy
| | - Francesco Bruno
- Regional Neurogenetic Centre (CRN), Department of Primary Care, ASP, 88046, Lamezia Terme, Catanzaro, Italy
- Association for Neurogenetic Research (ARN), 88046, Lamezia Terme, Italy
| | - Piergiorgio La Rosa
- Division of Neuroscience, Dept. of Psychology, University La Sapienza, Rome, Italy
- European Center for Brain Research, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Daniela Marazziti
- Institute of Biochemistry and Cell Biology, Italian National Research Council (CNR), I-00015, Monterotondo Scalo, Italy
| | - Maria Teresa Fiorenza
- Division of Neuroscience, Dept. of Psychology, University La Sapienza, Rome, Italy
- European Center for Brain Research, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Sonia Canterini
- Division of Neuroscience, Dept. of Psychology, University La Sapienza, Rome, Italy.
- European Center for Brain Research, IRCCS Fondazione Santa Lucia, Rome, Italy.
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Ruiz-Viroga V, de Ceglia M, Morelli L, Castaño EM, Calvo EB, Suárez J, Rodríguez de Fonseca F, Galeano P, Lagos P. Acute intrahippocampal administration of melanin-concentrating hormone impairs memory consolidation and decreases the expression of MCHR-1 and TrkB receptors. Prog Neuropsychopharmacol Biol Psychiatry 2023; 123:110703. [PMID: 36565982 DOI: 10.1016/j.pnpbp.2022.110703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 11/18/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
Interest in the role of melanin-concentrating hormone (MCH) in memory processes has increased in recent years, with some studies reporting memory-enhancing effects, while others report deleterious effects. Due to these discrepancies, this study seeks to provide new evidence about the role of MCH in memory consolidation and its relation with BDNF/TrkB system. To this end, in the first experiment, increased doses of MCH were acutely administered in both hippocampi to groups of male rats (25, 50, 200, and 500 ng). Microinjections were carried out immediately after finishing the sample trial of two hippocampal-dependent behavioral tasks: the Novel Object Recognition Test (NORT) and the modified Elevated Plus Maze (mEPM) test. Results indicated that a dose of 200 ng of MCH or higher impaired memory consolidation in both tasks. A second experiment was performed in which a dose of 200 ng of MCH was administered alone or co-administered with the MCHR-1 antagonist ATC-0175 at the end of the sample trial in the NORT. Results showed that MCH impaired memory consolidation, while the co-administration with ATC-0175 reverted this detrimental effect. Moreover, MCH induced a significant decrease in hippocampal MCHR-1 and TrkB expression with no modification in the expression of BDNF and NMDA receptor subunits NR1, NR2A, and NR2B. These results suggest that MCH in vivo elicits pro-amnesic effects in the rat hippocampus by decreasing the availability of its receptor and TrkB receptors, thus linking both endogenous systems to memory processes.
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Affiliation(s)
- Vicente Ruiz-Viroga
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Gral. Flores 2125, Montevideo ZP11800, Uruguay
| | - Marialuisa de Ceglia
- UGC Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Av. Carlos Haya 82, Málaga 29010, Spain.
| | - Laura Morelli
- Laboratory of Brain Aging and Neurodegeneration, Fundación Instituto Leloir (IIBBA-CONICET), Av. Patricias Argentinas 435, Ciudad Autónoma de Buenos Aires C1405BWE, Argentina.
| | - Eduardo M Castaño
- Laboratory of Brain Aging and Neurodegeneration, Fundación Instituto Leloir (IIBBA-CONICET), Av. Patricias Argentinas 435, Ciudad Autónoma de Buenos Aires C1405BWE, Argentina.
| | - Eduardo Blanco Calvo
- Instituto de Investigación Biomédica de Málaga (IBIMA), Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Universidad de Málaga, Campus de Teatinos S/N, Málaga 29071, Spain.
| | - Juan Suárez
- Instituto de Investigación Biomédica de Málaga (IBIMA), Departamento de Anatomía Humana, Medicina Legal e Historia de la Ciencia, Universidad de Málaga, Málaga 29071, Spain.
| | - Fernando Rodríguez de Fonseca
- UGC Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga, Universidad de Málaga, Av. Carlos Haya 82, Málaga 29010, Spain.
| | - Pablo Galeano
- Laboratory of Brain Aging and Neurodegeneration, Fundación Instituto Leloir (IIBBA-CONICET), Av. Patricias Argentinas 435, Ciudad Autónoma de Buenos Aires C1405BWE, Argentina.
| | - Patricia Lagos
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Gral. Flores 2125, Montevideo ZP11800, Uruguay.
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Focșa IO, Budișteanu M, Bălgrădean M. Clinical and genetic heterogeneity of primary ciliopathies (Review). Int J Mol Med 2021; 48:176. [PMID: 34278440 PMCID: PMC8354309 DOI: 10.3892/ijmm.2021.5009] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 06/28/2021] [Indexed: 01/11/2023] Open
Abstract
Ciliopathies comprise a group of complex disorders, with involvement of the majority of organs and systems. In total, >180 causal genes have been identified and, in addition to Mendelian inheritance, oligogenicity, genetic modifications, epistatic interactions and retrotransposon insertions have all been described when defining the ciliopathic phenotype. It is remarkable how the structural and functional impairment of a single, minuscule organelle may lead to the pathogenesis of highly pleiotropic diseases. Thus, combined efforts have been made to identify the genetic substratum and to determine the pathophysiological mechanism underlying the clinical presentation, in order to diagnose and classify ciliopathies. Yet, predicting the phenotype, given the intricacy of the genetic cause and overlapping clinical characteristics, represents a major challenge. In the future, advances in proteomics, cell biology and model organisms may provide new insights that could remodel the field of ciliopathies.
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Affiliation(s)
- Ina Ofelia Focșa
- Department of Medical Genetics, University of Medicine and Pharmacy 'Carol Davila', 021901 Bucharest, Romania
| | - Magdalena Budișteanu
- Department of Pediatric Neurology, 'Prof. Dr. Alexandru Obregia' Clinical Hospital of Psychiatry, 041914 Bucharest, Romania
| | - Mihaela Bălgrădean
- Department of Pediatrics and Pediatric Nephrology, Emergency Clinical Hospital for Children 'Maria Skłodowska Curie', 077120 Bucharest, Romania
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7
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Rouabhi M, Guo DF, Morgan DA, Zhu Z, López M, Zingman L, Grobe JL, Rahmouni K. BBSome ablation in SF1 neurons causes obesity without comorbidities. Mol Metab 2021; 48:101211. [PMID: 33722691 PMCID: PMC8065214 DOI: 10.1016/j.molmet.2021.101211] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/25/2021] [Accepted: 03/08/2021] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVES The hypothalamic ventromedial nucleus (VMH) plays a major role in metabolic control, but the molecular mechanisms involved remain poorly defined. We analyzed the relevance of the BBSome, a protein complex composed of 8 Bardet-Biedl syndrome (BBS) proteins including BBS1, in VMH steroidogenic factor 1 (SF1) neurons for the control of energy homeostasis and related physiological processes. METHODS We generated mice bearing selective BBSome disruption, through Bbs1 gene deletion, in SF1 neurons (SF1Cre/Bbs1fl/fl). We analyzed the consequence on body weight, glucose homeostasis, and cardiovascular autonomic function of BBSome loss in SF1 neurons. RESULTS SF1Cre/Bbs1fl/fl mice had increased body weight and adiposity under normal chow conditions. Food intake, energy absorption, and digestive efficiency were not altered by Bbs1 gene deletion in SF1 neurons. SF1Cre/Bbs1fl/fl mice exhibited lower energy expenditure, particularly during the dark cycle. Consistent with this finding, SF1Cre/Bbs1fl/fl mice displayed reduced sympathetic nerve traffic and expression of markers of thermogenesis in brown adipose tissue. SF1Cre/Bbs1fl/fl mice also had lower sympathetic nerve activity to subcutaneous white adipose tissue that was associated with a protein expression profile that promotes lipid accumulation. Notably, despite obesity and hyperinsulinemia, SF1Cre/Bbs1fl/fl mice did not exhibit significant changes in glucose metabolism, insulin sensitivity, blood pressure, and baroreflex sensitivity. CONCLUSIONS Our findings demonstrate that the SF1 neuron BBSome is necessary for the regulation of energy homeostasis through modulation of the activity of the sympathetic nervous system and that the SF1 neuron BBSome is required for the development of obesity-related comorbidities.
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Affiliation(s)
- Mohamed Rouabhi
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Deng-Fu Guo
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Veterans Affairs Health Care System, Iowa City, IA, USA
| | - Donald A Morgan
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Veterans Affairs Health Care System, Iowa City, IA, USA
| | - Zhiyong Zhu
- Veterans Affairs Health Care System, Iowa City, IA, USA; Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Miguel López
- NeurObesity Group, Department of Physiology, CiMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain
| | - Leonid Zingman
- Veterans Affairs Health Care System, Iowa City, IA, USA; Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Obesity Research and Education Initiative, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Justin L Grobe
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Obesity Research and Education Initiative, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Iowa Neuroscience Institute, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Kamal Rahmouni
- Department of Neuroscience and Pharmacology, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Veterans Affairs Health Care System, Iowa City, IA, USA; Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Obesity Research and Education Initiative, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Fraternal Order of Eagles Diabetes Research Center, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Iowa Neuroscience Institute, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
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8
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Huang J, Sun L, Mennigen JA, Liu Y, Liu S, Zhang M, Wang Q, Tu W. Developmental toxicity of the novel PFOS alternative OBS in developing zebrafish: An emphasis on cilia disruption. JOURNAL OF HAZARDOUS MATERIALS 2021; 409:124491. [PMID: 33223314 DOI: 10.1016/j.jhazmat.2020.124491] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 10/29/2020] [Accepted: 11/03/2020] [Indexed: 06/11/2023]
Abstract
In recent years, sodium p-perfluorous nonenoxybenzene sulfonate (OBS) has emerged as a substitute for PFOS with large demand and application in the Chinese market. However, little is known about potential developmental effects of OBS. In this study, zebrafish embryos were acutely exposed to different concentrations of OBS and the positive control PFOS for a comparative developmental toxicity assessment. OBS caused hatching delays, body axis curvature, neurobehavioral inhibition and abnormal cardiovascular development. These organismal effects were accompanied by change of development related genes expression profile, in which some cases were similar to PFOS. Overall, the toxic effects induced by OBS were generally milder than that of PFOS. Further investigation suggested that both OBS and PFOS disrupted ciliogenesis, evidenced by the ciliary immunostaining, changes in gene expression of kinesin family, dynein arm family and tubulin family members, as well as downregulation of the abundance of motor proteins including KIF3C, DYNC1H1 and DYNC1LI1. The influence of PFOS was stronger than that of OBS on ciliary genes and proteins. Molecular docking analysis revealed that both OBS and PFOS fitted into the motor proteins tightly, but binding affinity between OBS and motor proteins was lower than PFOS. Collectively, OBS and PFOS may act on ciliary motor proteins to interfere with ciliogenesis, leading to ciliary dysfunction and providing a novel probable action mode linked to developmental toxicity. This raises concerns regarding the health risks of the novel PFOS alternative OBS.
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Affiliation(s)
- Jing Huang
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, China; Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China
| | - Liwei Sun
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | | | - Yu Liu
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China
| | - Shuai Liu
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China
| | - Miao Zhang
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China
| | - Qiyu Wang
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China.
| | - Wenqing Tu
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330012, China.
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9
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Pak TK, Carter CS, Zhang Q, Huang SC, Searby C, Hsu Y, Taugher RJ, Vogel T, Cychosz CC, Genova R, Moreira NN, Stevens H, Wemmie JA, Pieper AA, Wang K, Sheffield VC. A mouse model of Bardet-Biedl Syndrome has impaired fear memory, which is rescued by lithium treatment. PLoS Genet 2021; 17:e1009484. [PMID: 33886537 PMCID: PMC8061871 DOI: 10.1371/journal.pgen.1009484] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 03/12/2021] [Indexed: 02/08/2023] Open
Abstract
Primary cilia are microtubule-based organelles present on most cells that regulate many physiological processes, ranging from maintaining energy homeostasis to renal function. However, the role of these structures in the regulation of behavior remains unknown. To study the role of cilia in behavior, we employ mouse models of the human ciliopathy, Bardet-Biedl Syndrome (BBS). Here, we demonstrate that BBS mice have significant impairments in context fear conditioning, a form of associative learning. Moreover, we show that postnatal deletion of BBS gene function, as well as congenital deletion, specifically in the forebrain, impairs context fear conditioning. Analyses indicated that these behavioral impairments are not the result of impaired hippocampal long-term potentiation. However, our results indicate that these behavioral impairments are the result of impaired hippocampal neurogenesis. Two-week treatment with lithium chloride partially restores the proliferation of hippocampal neurons which leads to a rescue of context fear conditioning. Overall, our results identify a novel role of cilia genes in hippocampal neurogenesis and long-term context fear conditioning.
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Affiliation(s)
- Thomas K. Pak
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Neuroscience Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Calvin S. Carter
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Qihong Zhang
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Sunny C. Huang
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Charles Searby
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Ying Hsu
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Rebecca J. Taugher
- Department of Psychiatry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Veterans Affairs Medical Center, Iowa City, Iowa, United States of America
| | - Tim Vogel
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Christopher C. Cychosz
- Department of Orthopedics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Rachel Genova
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Nina N. Moreira
- Department of Obstetrics and Gynecology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Hanna Stevens
- Neuroscience Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Psychiatry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - John A. Wemmie
- Neuroscience Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Psychiatry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Veterans Affairs Medical Center, Iowa City, Iowa, United States of America
- Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Andrew A. Pieper
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, Ohio, United States of America
- Department of Psychiatry, Case Western Reserve University, Cleveland, Ohio, United States of America
- Geriatric Psychiatry, GRECC, Louis Stokes Cleveland VA Medical Center; Cleveland, Ohio, United States of America
- Institute for Transformative Molecular Medicine, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Weill Cornell Autism Research Program, Weill Cornell Medicine of Cornell University, New York, United States of America
- Department of Neuroscience, Case Western Reserve University, School of Medicine, Cleveland, Ohio, United States of America
| | - Kai Wang
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, Iowa, United States of America
| | - Val C. Sheffield
- Neuroscience Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
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10
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BBS4 Is Essential for Nuclear Transport of Transcription Factors Mediating Neuronal ER Stress Response. Mol Neurobiol 2020; 58:78-91. [PMID: 32894499 DOI: 10.1007/s12035-020-02104-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/27/2020] [Indexed: 11/09/2022]
Abstract
Bardet-Biedl syndrome (BBS) is an autosomal recessive syndrome presenting with retinal dystrophy, cognitive impairment, and obesity. BBS is characterized by elevated endoplasmic reticulum (ER) stress in the early stages of adipocyte and retinal development. BBS expression in the CNS and indications of hippocampal dysgenesis suggest neural development abnormalities. However, the role of BBS in ER stress in neuronal cells has not yet been studied. Therefore, we aimed at studying the role of BBS4 in neuronal development under normal and ER stress conditions. ER stress and unfolded protein response (UPR) were studied in BBS4-silenced (SiBBS4) SH-SY5Y cells during differentiation under normal and stress states, using molecular and biochemical markers. ER stress was demonstrated at early neural differentiation, with significantly augmented expression of UPR markers corresponding to BBS4 expression. In the undifferentiated state, BBS4 silencing resulted in significantly reduced ER-stress markers' expression under normal and ER-stress states. Independent of ER stress, SiBBS4 cells demonstrated significant reduction in activated phospho-IRE1α. Under BBS4 silencing, both sXBP-1 and activated ATF6α p50 failed to translocate to the nucleus. Transcript levels of apoptosis markers were upregulated under BBS4 depletion and ER-stress induction, corresponding to decreased viability. BBS4 depletion in neuronal cells results in reduced sensitivity to ER stress during differentiation and under ER-stress induction, partly due to failure in translocation of ER-transcription factors (TF) sXBP-1 and ATF6α p50 to the nucleus. Hence, BBS4 is essential for nuclear transport under ER-stress response in neuronal cells during early differentiation. Our studies shed light on molecular mechanisms through which BBS4 malfunction alters neuronal ER stress response.
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11
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Abstract
Primary cilia project in a single copy from the surface of most vertebrate cell types; they detect and transmit extracellular cues to regulate diverse cellular processes during development and to maintain tissue homeostasis. The sensory capacity of primary cilia relies on the coordinated trafficking and temporal localization of specific receptors and associated signal transduction modules in the cilium. The canonical Hedgehog (HH) pathway, for example, is a bona fide ciliary signalling system that regulates cell fate and self-renewal in development and tissue homeostasis. Specific receptors and associated signal transduction proteins can also localize to primary cilia in a cell type-dependent manner; available evidence suggests that the ciliary constellation of these proteins can temporally change to allow the cell to adapt to specific developmental and homeostatic cues. Consistent with important roles for primary cilia in signalling, mutations that lead to their dysfunction underlie a pleiotropic group of diseases and syndromic disorders termed ciliopathies, which affect many different tissues and organs of the body. In this Review, we highlight central mechanisms by which primary cilia coordinate HH, G protein-coupled receptor, WNT, receptor tyrosine kinase and transforming growth factor-β (TGFβ)/bone morphogenetic protein (BMP) signalling and illustrate how defects in the balanced output of ciliary signalling events are coupled to developmental disorders and disease progression.
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Haq N, Schmidt-Hieber C, Sialana FJ, Ciani L, Heller JP, Stewart M, Bentley L, Wells S, Rodenburg RJ, Nolan PM, Forsythe E, Wu MC, Lubec G, Salinas P, Häusser M, Beales PL, Christou-Savina S. Loss of Bardet-Biedl syndrome proteins causes synaptic aberrations in principal neurons. PLoS Biol 2019; 17:e3000414. [PMID: 31479441 PMCID: PMC6743795 DOI: 10.1371/journal.pbio.3000414] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 09/13/2019] [Accepted: 08/19/2019] [Indexed: 02/07/2023] Open
Abstract
Bardet-Biedl syndrome (BBS), a ciliopathy, is a rare genetic condition characterised by retinal degeneration, obesity, kidney failure, and cognitive impairment. In spite of progress made in our general understanding of BBS aetiology, the molecular and cellular mechanisms underlying cognitive impairment in BBS remain elusive. Here, we report that the loss of BBS proteins causes synaptic dysfunction in principal neurons, providing a possible explanation for the cognitive impairment phenotype observed in BBS patients. Using synaptosomal proteomics and immunocytochemistry, we demonstrate the presence of Bbs proteins in the postsynaptic density (PSD) of hippocampal neurons. Loss of Bbs results in a significant reduction of dendritic spines in principal neurons of Bbs mouse models. Furthermore, we show that spine deficiency correlates with events that destabilise spine architecture, such as impaired spine membrane receptor signalling, known to be involved in the maintenance of dendritic spines. Our findings suggest a role for BBS proteins in dendritic spine homeostasis that may be linked to the cognitive phenotype observed in BBS.
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Affiliation(s)
- Naila Haq
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Christoph Schmidt-Hieber
- Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Fernando J. Sialana
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Lorenza Ciani
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Janosch P. Heller
- Institute of Neurology, University College London, London, United Kingdom
| | - Michelle Stewart
- MRC Harwell Institute, Mary Lyon Centre, Harwell Campus, Oxfordshire, United Kingdom
| | - Liz Bentley
- MRC Harwell Institute, Mary Lyon Centre, Harwell Campus, Oxfordshire, United Kingdom
| | - Sara Wells
- MRC Harwell Institute, Mary Lyon Centre, Harwell Campus, Oxfordshire, United Kingdom
| | - Richard J. Rodenburg
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Patrick M. Nolan
- MRC Harwell Institute, Mary Lyon Centre, Harwell Campus, Oxfordshire, United Kingdom
| | - Elizabeth Forsythe
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Michael C. Wu
- Neurodigitech, LLC, San Diego, California, United States of America
| | - Gert Lubec
- Programme in Proteomics, Paracelsus Private Medical University, Salzburg, Austria
| | - P. Salinas
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Michael Häusser
- Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Philip L. Beales
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Sofia Christou-Savina
- Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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13
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Satir P, Satir BH. The conserved ancestral signaling pathway from cilium to nucleus. J Cell Sci 2019; 132:132/15/jcs230441. [PMID: 31375541 DOI: 10.1242/jcs.230441] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022] Open
Abstract
Many signaling molecules are localized to both the primary cilium and nucleus. Localization of specific transmembrane receptors and their signaling scaffold molecules in the cilium is necessary for correct physiological function. After a specific signaling event, signaling molecules leave the cilium, usually in the form of an endocytic vesicle scaffold, and move to the nucleus, where they dissociate from the scaffold and enter the nucleus to affect gene expression. This ancient pathway probably arose very early in eukaryotic evolution as the nucleus and cilium co-evolved. Because there are similarities in molecular composition of the nuclear and ciliary pores the entry and exit of proteins in both organelles rely on similar mechanisms. In this Hypothesis, we propose that the pathway is a dynamic universal cilia-based signaling pathway with some variations from protists to man. Everywhere the cilium functions as an important organelle for molecular storage of certain key receptors and selection and concentration of their associated signaling molecules that move from cilium to nucleus. This could also have important implications for human diseases such as Huntington disease.
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Affiliation(s)
- Peter Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, NY 10461 .,B&P Nanobiology Consultants, 7 Byfield Lane, Greenwich, CT 06830, USA
| | - Birgit H Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, NY 10461.,B&P Nanobiology Consultants, 7 Byfield Lane, Greenwich, CT 06830, USA
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14
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Saito M, Sato T. [Current situation of researches on a sensor organelle, primary cilium, to understand the pathogenesis of ciliopathy]. Nihon Yakurigaku Zasshi 2019; 153:117-123. [PMID: 30867380 DOI: 10.1254/fpj.153.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Primary cilium is a membrane-protruding immotile sensory organelle. It had been supposed that the cilium was a static organelle for long periods. However, recent studies have uncovered that the cilium is dynamically organized organelle in a cell cycle-dependent manner; it is formed during G0/G1 phase and resorbed when the cells enter cell division cycle. Despite the primary cilium is very short and its surface area is extremely small, the cilium possesses a few kinds of G protein-coupled receptors, growth factor receptors and ion channels. Therefore, it can function as a signaling receptor for selective bioactive ligands and mechanical stresses. Dysregulation of the ciliary dynamics is linked with hereditary disorders, so called "ciliopathy", with clinical manifestations of microcephaly, polycystic kidney, situs inversus, polydactyly, and so on. No effective medical treatment for the ciliopathies has been available. Increasing evidences about the molecular mechanisms of ciliary dynamics and ciliary functions have revealed that enormous number of molecules regulate a cycle of ciliogenesis, cilium-derived signaling, ciliary resorption and elimination. However, it is a fact that research progress is far inferior to the full disclosure of the molecular mechanisms. Further studies are required to clarify the pathogenesis of the cilipathies. Moreover, efficient medical treatments are expected to be developed by pharmacological approaches.
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Affiliation(s)
- Masaki Saito
- Department of Molecular Pharmacology, Tohoku University School of Medicine
| | - Takeya Sato
- Department of Molecular Pharmacology, Tohoku University School of Medicine
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15
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Uytingco CR, Williams CL, Xie C, Shively DT, Green WW, Ukhanov K, Zhang L, Nishimura DY, Sheffield VC, Martens JR. BBS4 is required for intraflagellar transport coordination and basal body number in mammalian olfactory cilia. J Cell Sci 2019; 132:jcs222331. [PMID: 30665891 PMCID: PMC6432715 DOI: 10.1242/jcs.222331] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 01/11/2019] [Indexed: 12/16/2022] Open
Abstract
Bardet-Beidl syndrome (BBS) manifests from genetic mutations encoding for one or more BBS proteins. BBS4 loss impacts olfactory ciliation and odor detection, yet the cellular mechanisms remain unclear. Here, we report that Bbs4-/- mice exhibit shorter and fewer olfactory sensory neuron (OSN) cilia despite retaining odorant receptor localization. Within Bbs4-/- OSN cilia, we observed asynchronous rates of IFT-A/B particle movements, indicating miscoordination in IFT complex trafficking. Within the OSN dendritic knob, the basal bodies are dynamic, with incorporation of ectopically expressed centrin-2 and γ-tubulin occurring after nascent ciliogenesis. Importantly, BBS4 loss results in the reduction of basal body numbers separate from cilia loss. Adenoviral expression of BBS4 restored OSN cilia lengths and was sufficient to re-establish odor detection, but failed to rescue ciliary and basal body numbers. Our results yield a model for the plurality of BBS4 functions in OSNs that includes intraciliary and periciliary roles that can explain the loss of cilia and penetrance of ciliopathy phenotypes in olfactory neurons.
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Affiliation(s)
- Cedric R Uytingco
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Corey L Williams
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Chao Xie
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Dana T Shively
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Warren W Green
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Kirill Ukhanov
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | - Lian Zhang
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
| | | | - Val C Sheffield
- Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA
- Howard Hughes Medical Institute, University of Iowa, Iowa City, IA 52242, USA
| | - Jeffrey R Martens
- Department of Pharmacology and Therapeutics, Gainesville, FL 32610, USA
- Center for Smell and Taste, University of Florida College of Medicine, Gainesville, FL 32610, USA
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16
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Mourão A, Christensen ST, Lorentzen E. The intraflagellar transport machinery in ciliary signaling. Curr Opin Struct Biol 2016; 41:98-108. [PMID: 27393972 DOI: 10.1016/j.sbi.2016.06.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 06/07/2016] [Indexed: 01/12/2023]
Abstract
Cilia and flagella on eukaryotic cells are slender microtubule-based projections surrounded by a membrane with a unique lipid and protein composition. It is now appreciated that cilia in addition to their established roles in motility also constitute hubs for cellular signaling by sensing external environmental cues necessary for organ development and maintenance of human health. Pathways reported to rely on the cilium organelle include Hedgehog, TGF-β, Wnt, PDGFRα, integrin and DNA damage repair signaling. An emerging theme in ciliary signaling is the requirement for active transport of signaling components into and out of the cilium proper. Here, we review the current state-of-the-art regarding the importance of intraflagellar transport and BBSome multi-subunit complexes in ciliary signaling.
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Affiliation(s)
- André Mourão
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Søren T Christensen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen, Denmark.
| | - Esben Lorentzen
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
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17
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Sandholt CH, Grarup N, Pedersen O, Hansen T. Genome-wide association studies of human adiposity: Zooming in on synapses. Mol Cell Endocrinol 2015; 418 Pt 2:90-100. [PMID: 26427653 DOI: 10.1016/j.mce.2015.09.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/24/2015] [Accepted: 09/25/2015] [Indexed: 02/03/2023]
Abstract
The decade anniversary for genome-wide association studies (GWAS) is approaching, and this experimental approach has commenced a deeper understanding of the genetics underlying complex diseases. In obesity genetics the GIANT (Genetic Investigation of ANthropometric Traits) consortium has played a crucial role, recently with two comprehensive meta-analyses, one focusing on general obesity, analyzing body-mass index (BMI) and the other on fat distribution, focusing on waist-hip ratio adjusted for BMI. With the in silico methods applied in these two studies as the pivot, this review looks into some of the biological knowledge, beginning to emerge from the intricate genomic background behind the genetic determinants of human adiposity. These include synaptic dysfunction, where GWAS pinpoint potential new mechanisms in pathways already known to be linked with obesity.
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Affiliation(s)
- Camilla H Sandholt
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Niels Grarup
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Oluf Pedersen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Torben Hansen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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18
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Andersen MK, Sandholt CH. Recent Progress in the Understanding of Obesity: Contributions of Genome-Wide Association Studies. Curr Obes Rep 2015; 4:401-10. [PMID: 26374640 DOI: 10.1007/s13679-015-0173-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Since 2007, discovery of genetic variants associated with general obesity and fat distribution has advanced tremendously through genome-wide association studies (GWAS). Currently, the number of robustly associated loci is 190. Even though these loci explain <3 % of the variance, they have provided us a still emerging picture of genomic localization, frequency and effect size spectra, and hints of functional implications. The translation into biological knowledge has turned out to be an immense task. However, in silico enrichment analyses of genes involved in specific pathways or expressed in specific tissues have the power to suggest biological mechanisms underlying obesity. Inspired by this, we highlight genes in five loci potentially mechanistically linked to leptin-receptor trafficking and signaling in primary cilia. The clinical application of genetic knowledge as prediction, prevention, or treatment strategies is unfortunately still far from reality. Thus, despite major advances, further research is warranted to solve one of the greatest health problems in modern society.
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Affiliation(s)
- Mette Korre Andersen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 1, 2.sal, 2100, Copenhagen, Denmark.
| | - Camilla Helene Sandholt
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 1, 2.sal, 2100, Copenhagen, Denmark.
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19
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Novas R, Cardenas-Rodriguez M, Irigoín F, Badano JL. Bardet-Biedl syndrome: Is it only cilia dysfunction? FEBS Lett 2015; 589:3479-91. [PMID: 26231314 DOI: 10.1016/j.febslet.2015.07.031] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/14/2015] [Accepted: 07/15/2015] [Indexed: 01/12/2023]
Abstract
Bardet-Biedl syndrome (BBS) is a genetically heterogeneous, pleiotropic disorder, characterized by both congenital and late onset defects. From the analysis of the mutational burden in patients to the functional characterization of the BBS proteins, this syndrome has become a model for both understanding oligogenic patterns of inheritance and the biology of a particular cellular organelle: the primary cilium. Here we briefly review the genetics of BBS to then focus on the function of the BBS proteins, not only in the context of the cilium but also highlighting potential extra-ciliary roles that could be relevant to the etiology of the disorder. Finally, we provide an overview of how the study of this rare syndrome has contributed to the understanding of cilia biology and how this knowledge has informed on the cellular basis of different clinical manifestations that characterize BBS and the ciliopathies.
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Affiliation(s)
- Rossina Novas
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay
| | | | - Florencia Irigoín
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay; Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Gral. Flores 2125, Montevideo CP11800, Uruguay
| | - Jose L Badano
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay.
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20
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Primary cilia and autophagic dysfunction in Huntington's disease. Cell Death Differ 2015; 22:1413-24. [PMID: 26160070 DOI: 10.1038/cdd.2015.80] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 05/04/2015] [Accepted: 05/13/2015] [Indexed: 02/07/2023] Open
Abstract
Huntington's disease (HD) is an inherited, neurodegenerative disorder caused by a single-gene mutation: a CAG expansion in the huntingtin (HTT) gene that results in production of a mutated protein, mutant HTT, with a polyglutamine tail (polyQ-HTT). Although the molecular pathways of polyQ-HTT toxicity are not fully understood, because protein misfolding and aggregation are central features of HD, it has long been suspected that cellular housekeeping processes such as autophagy might be important to disease pathology. Indeed, multiple lines of research have identified abnormal autophagy in HD, characterized generally by increased autophagic induction and inefficient clearance of substrates. To date, the origin of autophagic dysfunction in HD remains unclear and the search for actors involved continues. To that end, recent studies have suggested a bidirectional relationship between autophagy and primary cilia, signaling organelles of most mammalian cells. Interestingly, primary cilia structure is defective in HD, suggesting a potential link between autophagic dysfunction, primary cilia and HD pathogenesis. In addition, because polyQ-HTT also accumulates in primary cilia, the possibility exists that primary cilia might play additional roles in HD: perhaps by disrupting signaling pathways or acting as a reservoir for secretion and propagation of toxic, misfolded polyQ-HTT fragments. Here, we review recent research suggesting potential links between autophagy, primary cilia and HD and speculate on possible pathogenic mechanisms and future directions for the field.
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