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Kumar P. Portal Hypertension Due to TULP3-related Ciliopathy: First Report From the Asia-Pacific Region. J Clin Exp Hepatol 2024; 14:101478. [PMID: 39183737 PMCID: PMC11339038 DOI: 10.1016/j.jceh.2024.101478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 06/29/2024] [Indexed: 08/27/2024] Open
Affiliation(s)
- Pramod Kumar
- Hepatologist and Liver Transplant Physician, Gleneagles BGS Hospital, Bengaluru, Karnataka, India
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2
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Reddy Palicharla V, Mukhopadhyay S. Molecular and structural perspectives on protein trafficking to the primary cilium membrane. Biochem Soc Trans 2024; 52:1473-1487. [PMID: 38864436 PMCID: PMC11346432 DOI: 10.1042/bst20231403] [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: 03/20/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/13/2024]
Abstract
The primary cilium is a dynamic subcellular compartment templated from the mother centriole or basal body. Cilia are solitary and tiny, but remarkably consequential in cellular pathways regulating proliferation, differentiation, and maintenance. Multiple transmembrane proteins such as G-protein-coupled receptors, channels, enzymes, and membrane-associated lipidated proteins are enriched in the ciliary membrane. The precise regulation of ciliary membrane content is essential for effective signal transduction and maintenance of tissue homeostasis. Surprisingly, a few conserved molecular factors, intraflagellar transport complex A and the tubby family adapter protein TULP3, mediate the transport of most membrane cargoes into cilia. Recent advances in cryogenic electron microscopy provide fundamental insights into these molecular players. Here, we review the molecular players mediating cargo delivery into the ciliary membrane through the lens of structural biology. These mechanistic insights into ciliary transport provide a framework for understanding of disease variants in ciliopathies, enable precise manipulation of cilia-mediated pathways, and provide a platform for the development of targeted therapeutics.
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Affiliation(s)
- Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, U.S.A
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, U.S.A
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3
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Zhang C, Rehman M, Tian X, Pei SLC, Gu J, Bell TA, Dong K, Tham MS, Cai Y, Wei Z, Behrens F, Jetten AM, Zhao H, Lek M, Somlo S. Glis2 is an early effector of polycystin signaling and a target for therapy in polycystic kidney disease. Nat Commun 2024; 15:3698. [PMID: 38693102 PMCID: PMC11063051 DOI: 10.1038/s41467-024-48025-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 04/15/2024] [Indexed: 05/03/2024] Open
Abstract
Mouse models of autosomal dominant polycystic kidney disease (ADPKD) show that intact primary cilia are required for cyst growth following the inactivation of polycystin-1. The signaling pathways underlying this process, termed cilia-dependent cyst activation (CDCA), remain unknown. Using translating ribosome affinity purification RNASeq on mouse kidneys with polycystin-1 and cilia inactivation before cyst formation, we identify the differential 'CDCA pattern' translatome specifically dysregulated in kidney tubule cells destined to form cysts. From this, Glis2 emerges as a candidate functional effector of polycystin signaling and CDCA. In vitro changes in Glis2 expression mirror the polycystin- and cilia-dependent changes observed in kidney tissue, validating Glis2 as a cell culture-based indicator of polycystin function related to cyst formation. Inactivation of Glis2 suppresses polycystic kidney disease in mouse models of ADPKD, and pharmacological targeting of Glis2 with antisense oligonucleotides slows disease progression. Glis2 transcript and protein is a functional target of CDCA and a potential therapeutic target for treating ADPKD.
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Affiliation(s)
- Chao Zhang
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Michael Rehman
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Xin Tian
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Steven Lim Cho Pei
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Jianlei Gu
- Department of Biostatistics, Yale University School of Public Health, New Haven, CT, USA
| | | | - Ke Dong
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Ming Shen Tham
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Yiqiang Cai
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Zemeng Wei
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Felix Behrens
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Anton M Jetten
- Cell Biology Section, Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Hongyu Zhao
- Department of Biostatistics, Yale University School of Public Health, New Haven, CT, USA
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
- Computational Biology and Bioinformatics Program, Yale University, New Haven, CT, USA
| | - Monkol Lek
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Stefan Somlo
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA.
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA.
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4
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Yuan X, Kadowaki T. Protein subcellular relocalization and function of duplicated flagellar calcium binding protein genes in honey bee trypanosomatid parasite. PLoS Genet 2024; 20:e1011195. [PMID: 38437202 PMCID: PMC10939215 DOI: 10.1371/journal.pgen.1011195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 03/14/2024] [Accepted: 02/23/2024] [Indexed: 03/06/2024] Open
Abstract
The honey bee trypanosomatid parasite, Lotmaria passim, contains two genes that encode the flagellar calcium binding protein (FCaBP) through tandem duplication in its genome. FCaBPs localize in the flagellum and entire body membrane of L. passim through specific N-terminal sorting sequences. This finding suggests that this is an example of protein subcellular relocalization resulting from gene duplication, altering the intracellular localization of FCaBP. However, this phenomenon may not have occurred in Leishmania, as one or both of the duplicated genes have become pseudogenes. Multiple copies of the FCaBP gene are present in several Trypanosoma species and Leptomonas pyrrhocoris, indicating rapid evolution of this gene in trypanosomatid parasites. The N-terminal flagellar sorting sequence of L. passim FCaBP1 is in close proximity to the BBSome complex, while that of Trypanosoma brucei FCaBP does not direct GFP to the flagellum in L. passim. Deletion of the two FCaBP genes in L. passim affected growth and impaired flagellar morphogenesis and motility, but it did not impact host infection. Therefore, FCaBP represents a duplicated gene with a rapid evolutionary history that is essential for flagellar structure and function in a trypanosomatid parasite.
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Affiliation(s)
- Xuye Yuan
- Department of Biological Sciences, School of Science, Xi'an Jiaotong-Liverpool University, Suzhou Dushu Lake Higher Education Town, Jiangsu Province, China
| | - Tatsuhiko Kadowaki
- Department of Biological Sciences, School of Science, Xi'an Jiaotong-Liverpool University, Suzhou Dushu Lake Higher Education Town, Jiangsu Province, China
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5
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Moran AL, Louzao-Martinez L, Norris DP, Peters DJM, Blacque OE. Transport and barrier mechanisms that regulate ciliary compartmentalization and ciliopathies. Nat Rev Nephrol 2024; 20:83-100. [PMID: 37872350 DOI: 10.1038/s41581-023-00773-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2023] [Indexed: 10/25/2023]
Abstract
Primary cilia act as cell surface antennae, coordinating cellular responses to sensory inputs and signalling molecules that regulate developmental and homeostatic pathways. Cilia are therefore critical to physiological processes, and defects in ciliary components are associated with a large group of inherited pleiotropic disorders - known collectively as ciliopathies - that have a broad spectrum of phenotypes and affect many or most tissues, including the kidney. A central feature of the cilium is its compartmentalized structure, which imparts its unique molecular composition and signalling environment despite its membrane and cytosol being contiguous with those of the cell. Such compartmentalization is achieved via active transport pathways that bring protein cargoes to and from the cilium, as well as gating pathways at the ciliary base that establish diffusion barriers to protein exchange into and out of the organelle. Many ciliopathy-linked proteins, including those involved in kidney development and homeostasis, are components of the compartmentalizing machinery. New insights into the major compartmentalizing pathways at the cilium, namely, ciliary gating, intraflagellar transport, lipidated protein flagellar transport and ciliary extracellular vesicle release pathways, have improved our understanding of the mechanisms that underpin ciliary disease and associated renal disorders.
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Affiliation(s)
- Ailis L Moran
- School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Laura Louzao-Martinez
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Dorien J M Peters
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland.
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6
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Ponticelli C, Moroni G, Reggiani F. Autosomal Dominant Polycystic Kidney Disease: Is There a Role for Autophagy? Int J Mol Sci 2023; 24:14666. [PMID: 37834113 PMCID: PMC10572907 DOI: 10.3390/ijms241914666] [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: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
Autosomal-Dominant Polycystic Kidney Disease (ADPKD) is a monogenic disorder initiated by mutations in either PKD1 or PKD2 genes, responsible for encoding polycystin 1 and polycystin 2, respectively. These proteins are primarily located within the primary cilia. The disease follows an inexorable progression, leading most patients to severe renal failure around the age of 50, and extra-renal complications are frequent. A cure for ADPKD remains elusive, but some measures can be employed to manage symptoms and slow cyst growth. Tolvaptan, a vasopressin V2 receptor antagonist, is the only drug that has been proven to attenuate ADPKD progression. Recently, autophagy, a cellular recycling system that facilitates the breakdown and reuse of aged or damaged cellular components, has emerged as a potential contributor to the pathogenesis of ADPKD. However, the precise role of autophagy in ADPKD remains a subject of investigation, displaying a potentially twofold impact. On the one hand, impaired autophagy may promote cyst formation by inducing apoptosis, while on the other hand, excessive autophagy may lead to fibrosis through epithelial to mesenchymal transition. Promising results of autophagy inducers have been observed in preclinical studies. Clinical trials are warranted to thoroughly assess the long-term safety and efficacy of a combination of autophagy inducers with metabolic and/or aquaferetic drugs. This research aims to shed light on the complex involvement of autophagy in ADPKD, explore the regulation of autophagy in disease progression, and highlight the potential of combination therapies as a promising avenue for future investigations.
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Affiliation(s)
| | - Gabriella Moroni
- Nephrology and Dialysis Unit, IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089 Milan, Italy;
| | - Francesco Reggiani
- Nephrology and Dialysis Unit, IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089 Milan, Italy;
- Department of Biomedical Sciences, Humanitas University, 20090 Milan, Italy
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7
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Bi Y, Ren D, Yuan F, Zhang Z, Zhou D, Yi X, Ji L, Li K, Yang F, Wu X, Li X, Xu Y, Liu Y, Wang P, Cai C, Liu C, Ma Q, He L, Shi Y, He G. TULP4, a novel E3 ligase gene, participates in neuronal migration as a candidate in schizophrenia. CNS Neurosci Ther 2023. [PMID: 37650344 DOI: 10.1111/cns.14423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 07/26/2023] [Accepted: 08/14/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND TUB-like protein 4 (TULP4) is one of the distant members of tubby family proteins, whose function remains largely unknown. In the present study, we intend to identify the role of TULP4 in schizophrenia from human samples and animal models. METHODS Whole-exome sequencing was used to detect the four schizophrenia families collected. In different cell lines, the effects of identified variants in TULP4 gene on its expression and localization were analyzed. Knockdown models in utero and adult mice were employed to investigate the role of Tulp4 on neuronal migration and schizophrenia-related behavior. Subsequently, co-IP assays were used to search for proteins that interact with TULP4 and the effects of mutants on the molecular function of TULP4. RESULTS For the first time, we identified five rare variants in TULP4 from schizophrenia families, of which three significantly reduced TULP4 protein expression. Knockdown the expression of Tulp4 delayed neuronal migration during embryological development and consequently triggered abnormal behaviors in adult mice, including impaired sensorimotor gating and cognitive dysfunction. Furthermore, we confirmed that TULP4 is involved in the formation of a novel E3 ligase through interaction with CUL5-ELOB/C-RNF7 and the three deleterious variants affected the binding amount of TULP4 and CUL5 to a certain extent. CONCLUSIONS Together, we believe TULP4 plays an important role in neurodevelopment and subsequent schizophrenic-related phenotypes through its E3 ubiquitin ligase function.
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Affiliation(s)
- Yan Bi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Decheng Ren
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fan Yuan
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhou Zhang
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Burning Rock Biotech, Guangzhou, China
| | - Daizhan Zhou
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xin Yi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lei Ji
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Keyi Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fengping Yang
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xi Wu
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xingwang Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yifeng Xu
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yun Liu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Peng Wang
- Wuhu Fourth People's Hospital, Wuhu, China
| | | | - Chuanxin Liu
- School of Mental Health, Jining Medical University, Jining, China
| | - Qian Ma
- Laboratory Animal Centre, Shanghai Jiao Tong University, Shanghai, China
| | - Lin He
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi Shi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Guang He
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai, China
- The Collaborative Innovation Center for Brain Science, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Yang Y, Zhou J, Zhang D, Lv J, Chen M, Wang C, Song M, He F, Song S, Mei C. Dehydration Accelerates Cytogenesis and Cyst Growth in Pkd1 -/- Mice by Regulating Macrophage M2 Polarization. Inflammation 2023; 46:1272-1289. [PMID: 36997763 DOI: 10.1007/s10753-023-01806-5] [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: 12/15/2022] [Revised: 03/13/2023] [Accepted: 03/13/2023] [Indexed: 04/01/2023]
Abstract
Adult autosomal dominant polycystic kidney disease (ADPKD) has been shown to be related as a "third hit" to the occurrence of acute or chronic kidney injury. Here, we examined whether dehydration, as a common kidney risk factor, could cause cystogenesis in chronic-onset Pkd1-/- mice by regulating macrophage activation. First, we confirmed that dehydration accelerated cytogenesis in Pkd1-/- mice and that macrophages infiltrated the kidney tissues even earlier than macroscopic cyst formation. Then, microarray analysis suggested that glycolysis pathway may be involved in macrophage activation in Pkd1-/- kidneys under conditions of dehydration. Further, we confirmed glycolysis pathway was activated and lactic acid (L-LA) was overproduced in the Pkd1-/- kidney under conditions of dehydration. We have already proved that L-LA strongly stimulated M2 macrophage polarization and overproduction of polyamine in macrophage in vitro, and in the present study, we further discovered that M2 polarization-induced polyamine production shortened the primary cilia length by disrupting the PC1/PC2 complex. Finally, the activation of L-LA-arginase 1-polyamine pathway contributed to cystogenesis and progressive cyst growth in Pkd1-/- mice recurrently exposed to dehydration.
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Affiliation(s)
- Yang Yang
- Department of Nephrology, The 981th Hospital of Joint Logistic Support Force of Chinese People's Liberation Army, Puning Road, No.3, Shuangqiao District, Chengde, China.
- Kidney Diagnostic and Therapeutic Center of People's Liberation Army, Beidaihe Rehabilitation and Recuperation Center of the Chinese People's Liberation Army, Qinhuangdao, China.
| | - Jie Zhou
- Department of Nephrology, Affiliated Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Dongjuan Zhang
- Department of Nephrology, The 981th Hospital of Joint Logistic Support Force of Chinese People's Liberation Army, Puning Road, No.3, Shuangqiao District, Chengde, China
| | - Jiayi Lv
- Kidney Institution of the Chinese People's Liberation Army, Changzheng Hospital, The Navy Military Medical University, Fengyang Road, No.415, Huangpu District, Shanghai, China
| | - Meihan Chen
- Department of Nephrology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, China
| | - Chao Wang
- Kidney Diagnostic and Therapeutic Center of People's Liberation Army, Beidaihe Rehabilitation and Recuperation Center of the Chinese People's Liberation Army, Qinhuangdao, China
| | - Minghui Song
- Clinical Laboratory, Hainan Hospital of General Hospital of Chinese People's Liberation Army, Sanya, China
| | - Fagui He
- Department of Nephrology, The 981th Hospital of Joint Logistic Support Force of Chinese People's Liberation Army, Puning Road, No.3, Shuangqiao District, Chengde, China
| | - Shuwei Song
- Kidney Institution of the Chinese People's Liberation Army, Changzheng Hospital, The Navy Military Medical University, Fengyang Road, No.415, Huangpu District, Shanghai, China
| | - Changlin Mei
- Kidney Institution of the Chinese People's Liberation Army, Changzheng Hospital, The Navy Military Medical University, Fengyang Road, No.415, Huangpu District, Shanghai, China.
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9
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Van Sciver RE, Long AB, Katz HG, Gigante ED, Caspary T. Ciliary ARL13B inhibits developmental kidney cystogenesis in mouse. Dev Biol 2023; 500:1-9. [PMID: 37209936 PMCID: PMC10330881 DOI: 10.1016/j.ydbio.2023.05.004] [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: 02/08/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 05/22/2023]
Abstract
ARL13B is a small GTPase enriched in cilia. Deletion of Arl13b in mouse kidney results in renal cysts and an associated absence of primary cilia. Similarly, ablation of cilia leads to kidney cysts. To investigate whether ARL13B functions from within cilia to direct kidney development, we examined kidneys of mice expressing an engineered cilia-excluded ARL13B variant, ARL13BV358A. These mice retained renal cilia and developed cystic kidneys. Because ARL13B functions as a guanine nucleotide exchange factor (GEF) for ARL3, we examined kidneys of mice expressing an ARL13B variant that lacks ARL3 GEF activity, ARL13BR79Q. We found normal kidney development with no evidence of cysts in these mice. Taken together, our results show that ARL13B functions within cilia to inhibit renal cystogenesis during mouse development, and that this function does not depend on its role as a GEF for ARL3.
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Affiliation(s)
- Robert E Van Sciver
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
| | - Alyssa B Long
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
| | - Harrison G Katz
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Department of Biology, Brown University, Providence, RI, 02912, USA.
| | - Eduardo D Gigante
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Graduate Program in Neuroscience, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA; Department of Biology, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA, 30322, USA.
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10
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Thallmair V, Schultz L, Evers S, Jolie T, Goecke C, Leitner MG, Thallmair S, Oliver D. Localization of the tubby domain, a PI(4,5)P2 biosensor, to E-Syt3-rich endoplasmic reticulum-plasma membrane junctions. J Cell Sci 2023; 136:jcs260848. [PMID: 37401342 PMCID: PMC10445746 DOI: 10.1242/jcs.260848] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 06/26/2023] [Indexed: 07/05/2023] Open
Abstract
The phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] acts as a signaling lipid at the plasma membrane (PM) with pleiotropic regulatory actions on multiple cellular processes. Signaling specificity might result from spatiotemporal compartmentalization of the lipid and from combinatorial binding of PI(4,5)P2 effector proteins to additional membrane components. Here, we analyzed the spatial distribution of tubbyCT, a paradigmatic PI(4,5)P2-binding domain, in live mammalian cells by total internal reflection fluorescence (TIRF) microscopy and molecular dynamics simulations. We found that unlike other well-characterized PI(4,5)P2 recognition domains, tubbyCT segregates into distinct domains within the PM. TubbyCT enrichment occurred at contact sites between PM and endoplasmic reticulum (ER) (i.e. at ER-PM junctions) as shown by colocalization with ER-PM markers. Localization to these sites was mediated in a combinatorial manner by binding to PI(4,5)P2 and by interaction with a cytosolic domain of extended synaptotagmin 3 (E-Syt3), but not other E-Syt isoforms. Selective localization to these structures suggests that tubbyCT is a novel selective reporter for a ER-PM junctional pool of PI(4,5)P2. Finally, we found that association with ER-PM junctions is a conserved feature of tubby-like proteins (TULPs), suggesting an as-yet-unknown function of TULPs.
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Affiliation(s)
- Veronika Thallmair
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
| | - Lea Schultz
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Saskia Evers
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Theresa Jolie
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Christian Goecke
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
| | - Michael G. Leitner
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, 6020 Innsbruck, Austria
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH&Co.KG, Birkendorfer Str. 65, 88400 Biberach an der Riß, Germany
| | - Sebastian Thallmair
- Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main, Germany
- Groningen Biomolecular Sciences and Biotechnology Institute and The Zernike Institute for Advanced Material, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Dominik Oliver
- Department of Neurophysiology, Institute of Physiology and Pathophysiology, Philipps University Marburg, 35037 Marburg, Germany
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps UniversityMarburg, 35037 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), Universities of Marburg and Giessen, 35032 Marburg, Germany
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11
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Mill P, Christensen ST, Pedersen LB. Primary cilia as dynamic and diverse signalling hubs in development and disease. Nat Rev Genet 2023; 24:421-441. [PMID: 37072495 PMCID: PMC7615029 DOI: 10.1038/s41576-023-00587-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 85.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2023] [Indexed: 04/20/2023]
Abstract
Primary cilia, antenna-like sensory organelles protruding from the surface of most vertebrate cell types, are essential for regulating signalling pathways during development and adult homeostasis. Mutations in genes affecting cilia cause an overlapping spectrum of >30 human diseases and syndromes, the ciliopathies. Given the immense structural and functional diversity of the mammalian cilia repertoire, there is a growing disconnect between patient genotype and associated phenotypes, with variable severity and expressivity characteristic of the ciliopathies as a group. Recent technological developments are rapidly advancing our understanding of the complex mechanisms that control biogenesis and function of primary cilia across a range of cell types and are starting to tackle this diversity. Here, we examine the structural and functional diversity of primary cilia, their dynamic regulation in different cellular and developmental contexts and their disruption in disease.
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Affiliation(s)
- Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, Scotland
| | | | - Lotte B Pedersen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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12
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Van Sciver RE, Long AB, Katz HG, Gigante ED, Caspary T. Ciliary ARL13B inhibits developmental kidney cystogenesis in mouse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.08.527739. [PMID: 36798281 PMCID: PMC9934666 DOI: 10.1101/2023.02.08.527739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
ARL13B is a small GTPase enriched in cilia. Deletion of Arl13b in mouse kidney results in renal cysts and an associated absence of primary cilia. Similarly, ablation of cilia leads to kidney cysts. To investigate whether ARL13B functions from within cilia to direct kidney development, we examined kidneys of mice expressing an engineered cilia-excluded ARL13B variant, ARL13BV358A. These mice retained renal cilia and developed cystic kidneys. Because ARL13B functions as a guanine nucleotide exchange factor (GEF) for ARL3, we examined kidneys of mice expressing an ARL13B variant that lacks ARL3 GEF activity, ARL13BR79Q. We found normal kidney development with no evidence of cysts in these mice. Taken together, our results show that ARL13B functions within cilia to inhibit renal cystogenesis during mouse development, and that this function does not depend on its role as a GEF for ARL3.
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Affiliation(s)
- Robert E. Van Sciver
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
| | - Alyssa B. Long
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
| | - Harrison G. Katz
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Present address: Department of Biology, Brown University, Providence, RI 02912, USA
| | - Eduardo D. Gigante
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Graduate Program in Neuroscience, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
- Present address: Department of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Atlanta, GA 30322, USA
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13
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Jiang M, Palicharla VR, Miller D, Hwang SH, Zhu H, Hixson P, Mukhopadhyay S, Sun J. Human IFT-A complex structures provide molecular insights into ciliary transport. Cell Res 2023; 33:288-298. [PMID: 36775821 PMCID: PMC10066299 DOI: 10.1038/s41422-023-00778-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/11/2023] [Indexed: 02/14/2023] Open
Abstract
Intraflagellar transport (IFT) complexes, IFT-A and IFT-B, form bidirectional trains that move along the axonemal microtubules and are essential for assembling and maintaining cilia. Mutations in IFT subunits lead to numerous ciliopathies involving multiple tissues. However, how IFT complexes assemble and mediate cargo transport lacks mechanistic understanding due to missing high-resolution structural information of the holo-complexes. Here we report cryo-EM structures of human IFT-A complexes in the presence and absence of TULP3 at overall resolutions of 3.0-3.9 Å. IFT-A adopts a "lariat" shape with interconnected core and peripheral subunits linked by structurally vital zinc-binding domains. TULP3, the cargo adapter, interacts with IFT-A through its N-terminal region, and interface mutations disrupt cargo transport. We also determine the molecular impacts of disease mutations on complex formation and ciliary transport. Our work reveals IFT-A architecture, sheds light on ciliary transport and IFT train formation, and enables the rationalization of disease mutations in ciliopathies.
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Affiliation(s)
- Meiqin Jiang
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Darcie Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Hanwen Zhu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Patricia Hixson
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Ji Sun
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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14
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Luo L, Roy S, Li L, Ma M. Polycystic kidney disease: novel insights into polycystin function. Trends Mol Med 2023; 29:268-281. [PMID: 36805211 DOI: 10.1016/j.molmed.2023.01.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 01/18/2023] [Accepted: 01/24/2023] [Indexed: 02/17/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is a life-threatening monogenic disease caused by mutations in PKD1 and PKD2 that encode polycystin 1 (PC1) and polycystin 2 (PC2). PC1/2 localize to cilia of renal epithelial cells, and their function is believed to embody an inhibitory activity that suppresses the cilia-dependent cyst activation (CDCA) signal. Consequently, PC deficiency results in activation of CDCA and stimulates cyst growth. Recently, re-expression of PCs in established cysts has been shown to reverse PKD. Thus, the mode of action of PCs resembles a 'counterbalance in cruise control' to maintain lumen diameter within a designated range. Herein we review recent studies that point to novel arenas for future PC research with therapeutic potential for ADPKD.
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Affiliation(s)
- Lingfei Luo
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, 400715, China
| | - Sudipto Roy
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Proteos, 61 Biopolis Drive, Singapore, 138673, Singapore; Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, Singapore, 119288, Singapore; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Li Li
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, 400715, China; Research Center of Stem cells and Ageing, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Ming Ma
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, 400715, China.
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15
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Garaycoechea JI, Quinlan C, Luijsterburg MS. Pathological consequences of DNA damage in the kidney. Nat Rev Nephrol 2023; 19:229-243. [PMID: 36702905 DOI: 10.1038/s41581-022-00671-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2022] [Indexed: 01/27/2023]
Abstract
DNA lesions that evade repair can lead to mutations that drive the development of cancer, and cellular responses to DNA damage can trigger senescence and cell death, which are associated with ageing. In the kidney, DNA damage has been implicated in both acute and chronic kidney injury, and in renal cell carcinoma. The susceptibility of the kidney to chemotherapeutic agents that damage DNA is well established, but an unexpected link between kidney ciliopathies and the DNA damage response has also been reported. In addition, human genetic deficiencies in DNA repair have highlighted DNA crosslinks, DNA breaks and transcription-blocking damage as lesions that are particularly toxic to the kidney. Genetic tools in mice, as well as advances in kidney organoid and single-cell RNA sequencing technologies, have provided important insights into how specific kidney cell types respond to DNA damage. The emerging view is that in the kidney, DNA damage affects the local microenvironment by triggering a damage response and cell proliferation to replenish injured cells, as well as inducing systemic responses aimed at reducing exposure to genotoxic stress. The pathological consequences of DNA damage are therefore key to the nephrotoxicity of DNA-damaging agents and the kidney phenotypes observed in human DNA repair-deficiency disorders.
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Affiliation(s)
- Juan I Garaycoechea
- Hubrecht Institute-KNAW, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Catherine Quinlan
- Department of Paediatrics, University of Melbourne, Parkville, Australia
- Department of Nephrology, Royal Children's Hospital, Melbourne, Australia
- Department of Kidney Regeneration, Murdoch Children's Research Institute, Melbourne, Australia
| | - Martijn S Luijsterburg
- Department of Human Genetics, Leiden University Medical Center (LUMC), Leiden, The Netherlands.
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16
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Mahajan D, Madugula V, Lu L. Rab8 and TNPO1 are ciliary transport adaptors for GTPase Arl13b by interacting with its RVEP motif-containing ciliary targeting sequence. J Biol Chem 2023; 299:104604. [PMID: 36907439 PMCID: PMC10124946 DOI: 10.1016/j.jbc.2023.104604] [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: 08/24/2022] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Arl13b, an ARF/Arl-family GTPase, is highly enriched in the cilium. Recent studies have established Arl13b as one of the most crucial regulators for ciliary organization, trafficking, and signaling. The ciliary localization of Arl13b is known to require the RVEP motif. However, its cognitive ciliary transport adaptor has been elusive. Here, by imaging the ciliary localization of truncation and point mutations, we defined the ciliary targeting sequence (CTS) of Arl13b as a C-terminal stretch of 17 amino acids containing the RVEP motif. We found Rab8-GDP, but not Rab8-GTP, and TNPO1 simultaneously and directly bind to the CTS of Arl13b in pull-down assays using cell lysates or purified recombinant proteins. Furthermore, Rab8-GDP substantially enhances the interaction between TNPO1 and CTS. Additionally, we determined that the RVEP motif is an essential element as its mutation abolishes the interaction of the CTS with Rab8-GDP and TNPO1 in pull-down and TurboID-based proximity ligation assays. Finally, knockdown of endogenous Rab8 or TNPO1 decreases the ciliary localization of endogenous Arl13b. Therefore, our results suggest Rab8 and TNPO1 might function together as a ciliary transport adaptor for Arl13b by interacting with its RVEP-containing CTS.
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Affiliation(s)
- Divyanshu Mahajan
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Viswanadh Madugula
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Lei Lu
- School of Biological Sciences, Nanyang Technological University, Singapore.
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17
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Palicharla VR, Hwang SH, Somatilaka BN, Legué E, Shimada IS, Familiari NE, Tran VM, Woodruff JB, Liem KF, Mukhopadhyay S. Interactions between TULP3 tubby domain and ARL13B amphipathic helix promote lipidated protein transport to cilia. Mol Biol Cell 2023; 34:ar18. [PMID: 36652335 PMCID: PMC10011728 DOI: 10.1091/mbc.e22-10-0473] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The primary cilium is a nexus for cell signaling and relies on specific protein trafficking for function. The tubby family protein TULP3 transports integral membrane proteins into cilia through interactions with the intraflagellar transport complex-A (IFT-A) and phosphoinositides. It was previously shown that short motifs called ciliary localization sequences (CLSs) are necessary and sufficient for TULP3-dependent ciliary trafficking of transmembrane cargoes. However, the mechanisms by which TULP3 regulates ciliary compartmentalization of nonintegral, membrane-associated proteins and whether such trafficking requires TULP3-dependent CLSs is unknown. Here we show that TULP3 is required for ciliary transport of the Joubert syndrome-linked palmitoylated GTPase ARL13B through a CLS. An N-terminal amphipathic helix, preceding the GTPase domain of ARL13B, couples with the TULP3 tubby domain for ciliary trafficking, irrespective of palmitoylation. ARL13B transport requires TULP3 binding to IFT-A but not to phosphoinositides, indicating strong membrane-proximate interactions, unlike transmembrane cargo transport requiring both properties of TULP3. TULP3-mediated trafficking of ARL13B also regulates ciliary enrichment of farnesylated and myristoylated downstream effectors of ARL13B. The lipidated cargoes show distinctive depletion kinetics from kidney epithelial cilia with relation to Tulp3 deletion-induced renal cystogenesis. Overall, these findings indicate an expanded role of the tubby domain in capturing analogous helical secondary structural motifs from diverse cargoes.
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Affiliation(s)
- Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | | | - Emilie Legué
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520
| | - Issei S Shimada
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Nicole E Familiari
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Vanna M Tran
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jeffrey B Woodruff
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Karel F Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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18
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Abstract
The assembly and maintenance of most cilia and eukaryotic flagella depends on intraflagellar transport (IFT), the bidirectional movement of multi-megadalton IFT trains along the axonemal microtubules. These IFT trains function as carriers, moving ciliary proteins between the cell body and the organelle. Whereas tubulin, the principal protein of cilia, binds directly to IFT particle proteins, the transport of other ciliary proteins and complexes requires adapters that link them to the trains. Large axonemal substructures, such as radial spokes, outer dynein arms and inner dynein arms, assemble in the cell body before attaching to IFT trains, using the adapters ARMC2, ODA16 and IDA3, respectively. Ciliary import of several membrane proteins involves the putative adapter tubby-like protein 3 (TULP3), whereas membrane protein export involves the BBSome, an octameric complex that co-migrates with IFT particles. Thus, cells employ a variety of adapters, each of which is substoichiometric to the core IFT machinery, to expand the cargo range of the IFT trains. This Review summarizes the individual and shared features of the known cargo adapters and discusses their possible role in regulating the transport capacity of the IFT pathway.
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Affiliation(s)
- Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
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19
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Jafari Khamirani H, Palicharla VR, Dastgheib SA, Dianatpour M, Imanieh MH, Tabei SS, Besse W, Mukhopadhyay S, Liem KF. A pathogenic variant of TULP3 causes renal and hepatic fibrocystic disease. Front Genet 2022; 13:1021037. [PMID: 36276950 PMCID: PMC9585244 DOI: 10.3389/fgene.2022.1021037] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/22/2022] [Indexed: 11/26/2022] Open
Abstract
Patient variants in Tubby Like Protein-3 (TULP3) have recently been associated with progressive fibrocystic disease in tissues and organs. TULP3 is a ciliary trafficking protein that links membrane-associated proteins to the intraflagellar transport complex A. In mice, mutations in Tulp3 drive phenotypes consistent with ciliary dysfunction which include renal cystic disease, as part of a ciliopathic spectrum. Here we report two sisters from consanguineous parents with fibrocystic renal and hepatic disease harboring a homozygous missense mutation in TULP3 (NM_003324.5: c.1144C>T, p.Arg382Trp). The R382W patient mutation resides within the C-terminal Tubby domain, a conserved domain required for TULP3 to associate with phosphoinositides. We show that inner medullary collecting duct-3 cells expressing the TULP3 R382W patient variant have a severely reduced ability to localize the membrane-associated proteins ARL13b, INPP5E, and GPR161 to the cilium, consistent with a loss of TULP3 function. These studies establish Arginine 382 as a critical residue in the Tubby domain, which is essential for TULP3-mediated protein trafficking within the cilium, and expand the phenotypic spectrum known to result from recessive deleterious mutations in TULP3.
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Affiliation(s)
| | - Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | | | - Mehdi Dianatpour
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran
- Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Hadi Imanieh
- Gastroenterohepatology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Sajjad Tabei
- Shiraz Nephro-Urology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Whitney Besse
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, CT, United States
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Karel F. Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
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20
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Cilleros-Rodriguez D, Martin-Morales R, Barbeito P, Deb Roy A, Loukil A, Sierra-Rodero B, Herranz G, Pampliega O, Redrejo-Rodriguez M, Goetz SC, Izquierdo M, Inoue T, Garcia-Gonzalo FR. Multiple ciliary localization signals control INPP5E ciliary targeting. eLife 2022; 11:e78383. [PMID: 36063381 PMCID: PMC9444247 DOI: 10.7554/elife.78383] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 08/21/2022] [Indexed: 12/04/2022] Open
Abstract
Primary cilia are sensory membrane protrusions whose dysfunction causes ciliopathies. INPP5E is a ciliary phosphoinositide phosphatase mutated in ciliopathies like Joubert syndrome. INPP5E regulates numerous ciliary functions, but how it accumulates in cilia remains poorly understood. Herein, we show INPP5E ciliary targeting requires its folded catalytic domain and is controlled by four conserved ciliary localization signals (CLSs): LLxPIR motif (CLS1), W383 (CLS2), FDRxLYL motif (CLS3) and CaaX box (CLS4). We answer two long-standing questions in the field. First, partial CLS1-CLS4 redundancy explains why CLS4 is dispensable for ciliary targeting. Second, the essential need for CLS2 clarifies why CLS3-CLS4 are together insufficient for ciliary accumulation. Furthermore, we reveal that some Joubert syndrome mutations perturb INPP5E ciliary targeting, and clarify how each CLS works: (i) CLS4 recruits PDE6D, RPGR and ARL13B, (ii) CLS2-CLS3 regulate association to TULP3, ARL13B, and CEP164, and (iii) CLS1 and CLS4 cooperate in ATG16L1 binding. Altogether, we shed light on the mechanisms of INPP5E ciliary targeting, revealing a complexity without known parallels among ciliary cargoes.
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Affiliation(s)
- Dario Cilleros-Rodriguez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
- Instituto de Investigación del Hospital Universitario de La Paz (IdiPAZ)MadridSpain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII)MadridSpain
| | - Raquel Martin-Morales
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
- Instituto de Investigación del Hospital Universitario de La Paz (IdiPAZ)MadridSpain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII)MadridSpain
| | - Pablo Barbeito
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
- Instituto de Investigación del Hospital Universitario de La Paz (IdiPAZ)MadridSpain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII)MadridSpain
| | - Abhijit Deb Roy
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Abdelhalim Loukil
- Department of Pharmacology and Cancer Biology, Duke University School of MedicineDurhamUnited States
| | - Belen Sierra-Rodero
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
- Instituto de Investigación del Hospital Universitario de La Paz (IdiPAZ)MadridSpain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII)MadridSpain
| | - Gonzalo Herranz
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
| | - Olatz Pampliega
- Department of Neurosciences, University of the Basque Country, Achucarro Basque Center for Neuroscience-UPV/EHULeioaSpain
| | - Modesto Redrejo-Rodriguez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
| | - Sarah C Goetz
- Department of Pharmacology and Cancer Biology, Duke University School of MedicineDurhamUnited States
| | - Manuel Izquierdo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
| | - Takanari Inoue
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Francesc R Garcia-Gonzalo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM)MadridSpain
- Instituto de Investigaciones Biomédicas “Alberto Sols” (IIBM), Consejo Superior de Investigaciones Científicas (CSIC)-UAMMadridSpain
- Instituto de Investigación del Hospital Universitario de La Paz (IdiPAZ)MadridSpain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III (ISCIII)MadridSpain
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21
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Wang W, Silva LM, Wang HH, Kavanaugh MA, Pottorf TS, Allard BA, Jacobs DT, Dong R, Cornelius JT, Chaturvedi A, Swenson-Fields KI, Fields TA, Pritchard MT, Sharma M, Slawson C, Wallace DP, Calvet JP, Tran PV. Ttc21b deficiency attenuates autosomal dominant polycystic kidney disease in a kidney tubular- and maturation-dependent manner. Kidney Int 2022; 102:577-591. [PMID: 35644283 PMCID: PMC9398994 DOI: 10.1016/j.kint.2022.04.034] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 04/21/2022] [Accepted: 04/29/2022] [Indexed: 01/26/2023]
Abstract
Primary cilia are sensory organelles built and maintained by intraflagellar transport (IFT) multiprotein complexes. Deletion of several IFT-B genes attenuates polycystic kidney disease (PKD) severity in juvenile and adult autosomal dominant polycystic kidney disease (ADPKD) mouse models. However, deletion of an IFT-A adaptor, Tulp3, attenuates PKD severity in adult mice only. These studies indicate that dysfunction of specific cilia components has potential therapeutic value. To broaden our understanding of cilia dysfunction and its therapeutic potential, we investigate the role of global deletion of an IFT-A gene, Ttc21b, in juvenile and adult mouse models of ADPKD. Both juvenile (postnatal day 21) and adult (six months of age) ADPKD mice exhibited kidney cysts, increased kidney weight/body weight ratios, lengthened kidney cilia, inflammation, and increased levels of the nutrient sensor, O-linked β-N-acetylglucosamine (O-GlcNAc). Deletion of Ttc21b in juvenile ADPKD mice reduced cortical collecting duct cystogenesis and kidney weight/body weight ratios, increased proximal tubular and glomerular dilations, but did not reduce cilia length, inflammation, nor O-GlcNAc levels. In contrast, Ttc21b deletion in adult ADPKD mice markedly attenuated kidney cystogenesis and reduced cilia length, inflammation, and O-GlcNAc levels. Thus, unlike IFT-B, the effect of Ttc21b deletion in mouse models of ADPKD is development-specific. Unlike an IFT-A adaptor, deleting Ttc21b in juvenile ADPKD mice is partially ameliorative. Thus, our studies suggest that different microenvironmental factors, found in distinct nephron segments and in developing versus mature stages, modify ciliary homeostasis and ADPKD pathobiology. Further, elevated levels of O-GlcNAc, which regulates cellular metabolism and ciliogenesis, may be a pathological feature of ADPKD.
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Affiliation(s)
- Wei Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Luciane M Silva
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Henry H Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Matthew A Kavanaugh
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Tana S Pottorf
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Bailey A Allard
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Damon T Jacobs
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Rouchen Dong
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Joseph T Cornelius
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Aakriti Chaturvedi
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Katherine I Swenson-Fields
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Timothy A Fields
- Department of Pathology and Laboratory Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Michele T Pritchard
- Pharmacology, Toxicology and Therapeutics, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Madhulika Sharma
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Chad Slawson
- Department of Biochemistry and Molecular Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Darren P Wallace
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - James P Calvet
- Department of Biochemistry and Molecular Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA.
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22
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Padhy B, Xie J, Wang R, Lin F, Huang CL. Channel Function of Polycystin-2 in the Endoplasmic Reticulum Protects against Autosomal Dominant Polycystic Kidney Disease. J Am Soc Nephrol 2022; 33:1501-1516. [PMID: 35835458 PMCID: PMC9342640 DOI: 10.1681/asn.2022010053] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 04/03/2022] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Mutations of PKD2, which encodes polycystin-2, cause autosomal dominant polycystic kidney disease (ADPKD). The prevailing view is that defects in polycystin-2-mediated calcium ion influx in the primary cilia play a central role in the pathogenesis of cyst growth. However, polycystin-2 is predominantly expressed in the endoplasmic reticulum (ER) and more permeable to potassium ions than to calcium ions. METHODS The trimeric intracellular cation (TRIC) channel TRIC-B is an ER-resident potassium channel that mediates potassium-calcium counterion exchange for inositol trisphosphate-mediated calcium ion release. Using TRIC-B as a tool, we examined the function of ER-localized polycystin-2 and its role in ADPKD pathogenesis in cultured cells, zebrafish, and mouse models. RESULTS Agonist-induced ER calcium ion release was defective in cells lacking polycystin-2 and reversed by exogenous expression of TRIC-B. Vice versa, exogenous polycystin-2 reversed an ER calcium-release defect in cells lacking TRIC-B. In a zebrafish model, expression of wild-type but not nonfunctional TRIC-B suppressed polycystin-2-deficient phenotypes. Similarly, these phenotypes were suppressed by targeting the ROMK potassium channel (normally expressed on the cell surface) to the ER. In cultured cells and polycystin-2-deficient zebrafish phenotypes, polycystin-2 remained capable of reversing the ER calcium release defect even when it was not present in the cilia. Transgenic expression of Tric-b ameliorated cystogenesis in the kidneys of conditional Pkd2-inactivated mice, whereas Tric-b deletion enhanced cystogenesis in Pkd2-heterozygous kidneys. CONCLUSIONS Polycystin-2 in the ER appears to be critical for anticystogenesis and likely functions as a potassium ion channel to facilitate potassium-calcium counterion exchange for inositol trisphosphate-mediated calcium release. The results advance the understanding of ADPKD pathogenesis and provides proof of principle for pharmacotherapy by TRIC-B activators.
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Affiliation(s)
- Biswajit Padhy
- Division of Nephrology, Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Jian Xie
- Division of Nephrology, Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Runping Wang
- Division of Nephrology, Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Fang Lin
- Department of Anatomy and Cell Biology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Chou-Long Huang
- Division of Nephrology, Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
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23
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Walker RV, Maranto A, Palicharla VR, Hwang SH, Mukhopadhyay S, Qian F. Cilia-Localized Counterregulatory Signals as Drivers of Renal Cystogenesis. Front Mol Biosci 2022; 9:936070. [PMID: 35832738 PMCID: PMC9272769 DOI: 10.3389/fmolb.2022.936070] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 12/18/2022] Open
Abstract
Primary cilia play counterregulatory roles in cystogenesis-they inhibit cyst formation in the normal renal tubule but promote cyst growth when the function of polycystins is impaired. Key upstream cilia-specific signals and components involved in driving cystogenesis have remained elusive. Recent studies of the tubby family protein, Tubby-like protein 3 (TULP3), have provided new insights into the cilia-localized mechanisms that determine cyst growth. TULP3 is a key adapter of the intraflagellar transport complex A (IFT-A) in the trafficking of multiple proteins specifically into the ciliary membrane. Loss of TULP3 results in the selective exclusion of its cargoes from cilia without affecting their extraciliary pools and without disrupting cilia or IFT-A complex integrity. Epistasis analyses have indicated that TULP3 inhibits cystogenesis independently of the polycystins during kidney development but promotes cystogenesis in adults when polycystins are lacking. In this review, we discuss the current model of the cilia-dependent cyst activation (CDCA) mechanism in autosomal dominant polycystic kidney disease (ADPKD) and consider the possible roles of ciliary and extraciliary polycystins in regulating CDCA. We then describe the limitations of this model in not fully accounting for how cilia single knockouts cause significant cystic changes either in the presence or absence of polycystins. Based on available data from TULP3/IFT-A-mediated differential regulation of cystogenesis in kidneys with deletion of polycystins either during development or in adulthood, we hypothesize the existence of cilia-localized components of CDCA (cCDCA) and cilia-localized cyst inhibition (CLCI) signals. We develop the criteria for cCDCA/CLCI signals and discuss potential TULP3 cargoes as possible cilia-localized components that determine cystogenesis in kidneys during development and in adult mice.
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Affiliation(s)
- Rebecca V. Walker
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anthony Maranto
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | | | - Sun-Hee Hwang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Saikat Mukhopadhyay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Feng Qian
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
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24
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Devane J, Ott E, Olinger EG, Epting D, Decker E, Friedrich A, Bachmann N, Renschler G, Eisenberger T, Briem-Richter A, Grabhorn EF, Powell L, Wilson IJ, Rice SJ, Miles CG, Wood K, Trivedi P, Hirschfield G, Pietrobattista A, Wohler E, Mezina A, Sobreira N, Agolini E, Maggiore G, Dahmer-Heath M, Yilmaz A, Boerries M, Metzger P, Schell C, Grünewald I, Konrad M, König J, Schlevogt B, Sayer JA, Bergmann C. Progressive liver, kidney, and heart degeneration in children and adults affected by TULP3 mutations. Am J Hum Genet 2022; 109:928-943. [PMID: 35397207 PMCID: PMC9118107 DOI: 10.1016/j.ajhg.2022.03.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 03/22/2022] [Indexed: 12/31/2022] Open
Abstract
Organ fibrosis is a shared endpoint of many diseases, yet underlying mechanisms are not well understood. Several pathways governed by the primary cilium, a sensory antenna present on most vertebrate cells, have been linked with fibrosis. Ciliopathies usually start early in life and represent a considerable disease burden. We performed massively parallel sequencing by using cohorts of genetically unsolved individuals with unexplained liver and kidney failure and correlated this with clinical, imaging, and histopathological analyses. Mechanistic studies were conducted with a vertebrate model and primary cells. We detected bi-allelic deleterious variants in TULP3, encoding a critical adaptor protein for ciliary trafficking, in a total of 15 mostly adult individuals, originating from eight unrelated families, with progressive degenerative liver fibrosis, fibrocystic kidney disease, and hypertrophic cardiomyopathy with atypical fibrotic patterns on histopathology. We recapitulated the human phenotype in adult zebrafish and confirmed disruption of critical ciliary cargo composition in several primary cell lines derived from affected individuals. Further, we show interaction between TULP3 and the nuclear deacetylase SIRT1, with roles in DNA damage repair and fibrosis, and report increased DNA damage ex vivo. Transcriptomic studies demonstrated upregulation of profibrotic pathways with gene clusters for hypertrophic cardiomyopathy and WNT and TGF-β signaling. These findings identify variants in TULP3 as a monogenic cause for progressive degenerative disease of major organs in which affected individuals benefit from early detection and improved clinical management. Elucidation of mechanisms crucial for DNA damage repair and tissue maintenance will guide novel therapeutic avenues for this and similar genetic and non-genomic diseases.
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Affiliation(s)
- John Devane
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Elisabeth Ott
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Eric G Olinger
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Daniel Epting
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, 79106 Freiburg, Germany
| | - Eva Decker
- Medizinische Genetik Mainz, Limbach Genetics, 55128 Mainz, Germany
| | - Anja Friedrich
- Medizinische Genetik Mainz, Limbach Genetics, 55128 Mainz, Germany
| | - Nadine Bachmann
- Medizinische Genetik Mainz, Limbach Genetics, 55128 Mainz, Germany
| | - Gina Renschler
- Medizinische Genetik Mainz, Limbach Genetics, 55128 Mainz, Germany
| | | | - Andrea Briem-Richter
- University Medical Center Hamburg-Eppendorf, Department of Pediatrics, 20251 Hamburg, Germany
| | - Enke Freya Grabhorn
- University Medical Center Hamburg-Eppendorf, Department of Pediatrics, 20251 Hamburg, Germany
| | - Laura Powell
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Ian J Wilson
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Sarah J Rice
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Colin G Miles
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Katrina Wood
- Histopathology Department, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE1 4LP, UK
| | - Palak Trivedi
- NIHR Birmingham BRC, Centre for Liver and Gastrointestinal Research, University of Birmingham, Birmingham B15 2TT, UK; Liver Unit, University Hospitals Birmingham, Birmingham B15 2GW, UK; Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham B15 2TT, UK; Institute of Applied Health Research, University of Birmingham, Birmingham B15 2TT, UK
| | - Gideon Hirschfield
- Toronto Centre for Liver Disease, University Health Network, Toronto, ON M6H 3M1, Canada
| | - Andrea Pietrobattista
- Hepatogastroenterology and Liver Transplant Unit and Medical Genetics Laboratory, IRCCS Bambino Gesù Children's Hospital, 00165 Rome, Italy
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Anya Mezina
- Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Nara Sobreira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Emanuele Agolini
- Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Giuseppe Maggiore
- Hepatogastroenterology and Liver Transplant Unit and Medical Genetics Laboratory, IRCCS Bambino Gesù Children's Hospital, 00165 Rome, Italy
| | - Mareike Dahmer-Heath
- Department of General Pediatrics, University Hospital Münster, 48149 Münster, Germany
| | - Ali Yilmaz
- Department of Cardiology I, University Hospital Münster, 48149 Münster, Germany
| | - Melanie Boerries
- Institute of Medical Bioinformatics and Systems Medicine Medical Center - University of Freiburg, Medical Faculty, University of Freiburg, 79110 Freiburg, Germany; The German Cancer Consortium, Partner Site Freiburg and Cancer Research Center, 69120 Heidelberg, Germany
| | - Patrick Metzger
- Institute of Medical Bioinformatics and Systems Medicine Medical Center - University of Freiburg, Medical Faculty, University of Freiburg, 79110 Freiburg, Germany
| | - Christoph Schell
- Institute for Pathology, Medical Center - University of Freiburg, Medical Faculty, University of Freiburg, 79002 Freiburg, Germany
| | - Inga Grünewald
- Institute for Pathology, University Hospital Münster, 48149 Münster, Germany
| | - Martin Konrad
- Department of General Pediatrics, University Hospital Münster, 48149 Münster, Germany
| | - Jens König
- Department of General Pediatrics, University Hospital Münster, 48149 Münster, Germany
| | - Bernhard Schlevogt
- Department of Internal Medicine B, Gastroenterology, University Hospital Münster, 48149 Münster, Germany
| | - John A Sayer
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK; Renal Services, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, UK; Newcastle Biomedical Research Centre, NIHR, Newcastle upon Tyne NE4 5PL, UK.
| | - Carsten Bergmann
- Department of Medicine IV, Faculty of Medicine, Medical Center-University of Freiburg, 79106 Freiburg, Germany; Medizinische Genetik Mainz, Limbach Genetics, 55128 Mainz, Germany.
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25
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Shimada IS, Kato Y. Ciliary signaling in stem cells in health and disease: Hedgehog pathway and beyond. Semin Cell Dev Biol 2022; 129:115-125. [PMID: 35466055 DOI: 10.1016/j.semcdb.2022.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 11/29/2022]
Abstract
The primary cilium is a hair-like sensory compartment that protrudes from the cellular surface. The primary cilium is enriched in a variety of signaling molecules that regulate cellular activities. Stem cells have primary cilia. They reside in a specialized environment, called the stem cell niche. This niche contains a variety of secreted factors, and some of their receptors are localized in the primary cilia of stem cells. Here, we summarize the current understanding of the function of cilia in compartmentalized signaling in stem cells. We describe how ciliary signaling regulates stem cells and progenitor cells during development, tissue homeostasis and tumorigenesis. We summarize our understanding of cilia regulated signaling -primary involving the hedgehog pathway- in stem cells in diverse settings that include neuroepithelial cells, radial glia, cerebellar granule neuron precursors, hematopoietic stem cells, hair follicle stem cells, bone marrow mesenchymal stem cells and mammary gland stem cells. Overall, our review highlights a variety of roles that ciliary signaling plays in regulating stem cells throughout life.
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Affiliation(s)
- Issei S Shimada
- Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University, 1 Azakawasumi, Mizuzho-cho, Mizuho-ku, Nagoya, 467-8601 Aichi, Japan.
| | - Yoichi Kato
- Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University, 1 Azakawasumi, Mizuzho-cho, Mizuho-ku, Nagoya, 467-8601 Aichi, Japan.
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26
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Senum SR, Li Y(SM, Benson KA, Joli G, Olinger E, Lavu S, Madsen CD, Gregory AV, Neatu R, Kline TL, Audrézet MP, Outeda P, Nau CB, Meijer E, Ali H, Steinman TI, Mrug M, Phelan PJ, Watnick TJ, Peters DJ, Ong AC, Conlon PJ, Perrone RD, Cornec-Le Gall E, Hogan MC, Torres VE, Sayer JA, Harris PC, Harris PC. Monoallelic IFT140 pathogenic variants are an important cause of the autosomal dominant polycystic kidney-spectrum phenotype. Am J Hum Genet 2022; 109:136-156. [PMID: 34890546 DOI: 10.1016/j.ajhg.2021.11.016] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/15/2021] [Indexed: 12/18/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD), characterized by progressive cyst formation/expansion, results in enlarged kidneys and often end stage kidney disease. ADPKD is genetically heterogeneous; PKD1 and PKD2 are the common loci (∼78% and ∼15% of families) and GANAB, DNAJB11, and ALG9 are minor genes. PKD is a ciliary-associated disease, a ciliopathy, and many syndromic ciliopathies have a PKD phenotype. In a multi-cohort/-site collaboration, we screened ADPKD-diagnosed families that were naive to genetic testing (n = 834) or for whom no PKD1 and PKD2 pathogenic variants had been identified (n = 381) with a PKD targeted next-generation sequencing panel (tNGS; n = 1,186) or whole-exome sequencing (WES; n = 29). We identified monoallelic IFT140 loss-of-function (LoF) variants in 12 multiplex families and 26 singletons (1.9% of naive families). IFT140 is a core component of the intraflagellar transport-complex A, responsible for retrograde ciliary trafficking and ciliary entry of membrane proteins; bi-allelic IFT140 variants cause the syndromic ciliopathy, short-rib thoracic dysplasia (SRTD9). The distinctive monoallelic phenotype is mild PKD with large cysts, limited kidney insufficiency, and few liver cysts. Analyses of the cystic kidney disease probands of Genomics England 100K showed that 2.1% had IFT140 LoF variants. Analysis of the UK Biobank cystic kidney disease group showed probands with IFT140 LoF variants as the third most common group, after PKD1 and PKD2. The proximity of IFT140 to PKD1 (∼0.5 Mb) in 16p13.3 can cause diagnostic confusion, and PKD1 variants could modify the IFT140 phenotype. Importantly, our studies link a ciliary structural protein to the ADPKD spectrum.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Peter C Harris
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA.
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27
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Li ZH, Zhou JH, Chen SN, Pan L, Feng Y, Luo MQ, Li RX, Sun GL. MicroRNA-506 has a suppressive effect on the tumorigenesis of nonsmall-cell lung cancer by regulating tubby-like protein 3. Bioengineered 2021; 12:10176-10186. [PMID: 34874810 PMCID: PMC8810049 DOI: 10.1080/21655979.2021.2001216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/28/2021] [Accepted: 10/28/2021] [Indexed: 12/31/2022] Open
Abstract
MicroRNA-506 (miR-506), a miRNA, has been proven to act as a tumor suppressor gene in nonsmall-cell lung cancer (NSCLC); Tubby-like protein 3 (TULP3) is a potential target gene of miR-506. This study investigates whether miR-506 can prevent NSCLC progression by mediating TULP3. In vivo and in vitro experiments were performed to explore the function and potential regulatory relationship of miR-506 and TULP3 in NSCLC. Our results revealed that miR-506 is high expression in NSCLC cell lines, and the overexpression of miR-506 could inhibit cell viability and enhance cell apoptosis in H1299 and A549 cells. Pro-apoptotic related protein (cytochrome C, Bax, and cleaved caspase-9) expression increased while anti-apoptotic related protein (BCL-2 and BCL-XL) expression decreased after miR-506 was overexpression. Meanwhile, the overexpression of miR-506 could notably downregulate TULP3. Additionally, silence of TULP3 inhibited cell viability and promoted cell apoptosis. At the same time, pro-apoptotic related protein expression was promoted while anti-apoptotic related protein expression was inhibited. Furthermore, TULP3 overexpression could markedly reverse the inhibitory effect of miR-506 on the proliferation and induction of mitochondrial apoptosis in H1299 and A549 cells. In vivo tumor formation experiments also exhibited consistent results indicating that the functions of TULP3 might be correlated with the promotion of tumorigenesis. In conclusion, we firstly found that miR-506 can be involved in the processes of NSCLC and exert a suppressive effect on tumorigenesis by regulating TULP3 expression.
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Affiliation(s)
- Zhan-Hua Li
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Ji-Hong Zhou
- Department of Respiratory Medicine, Shenzhen Baoan Hospital of Traditional Chinese Medicine, Shenzhen, China
| | - Si-Ning Chen
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Ling Pan
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Yuan Feng
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Mei-Qun Luo
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Rui-Xiang Li
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
| | - Gui-Li Sun
- Department of Respiratory and Critical Care Medicine, Ruikang Hospital Affiliated to Guangxi Traditional Chinese Medicine University, Nanning, China
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28
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Wu CT, Hilgendorf KI, Bevacqua RJ, Hang Y, Demeter J, Kim SK, Jackson PK. Discovery of ciliary G protein-coupled receptors regulating pancreatic islet insulin and glucagon secretion. Genes Dev 2021; 35:1243-1255. [PMID: 34385262 PMCID: PMC8415323 DOI: 10.1101/gad.348261.121] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 07/02/2021] [Indexed: 01/17/2023]
Abstract
Multiple G protein-coupled receptors (GPCRs) are expressed in pancreatic islet cells, but the majority have unknown functions. We observed specific GPCRs localized to primary cilia, a prominent signaling organelle, in pancreatic α and β cells. Loss of cilia disrupts β-cell endocrine function, but the molecular drivers are unknown. Using functional expression, we identified multiple GPCRs localized to cilia in mouse and human islet α and β cells, including FFAR4, PTGER4, ADRB2, KISS1R, and P2RY14. Free fatty acid receptor 4 (FFAR4) and prostaglandin E receptor 4 (PTGER4) agonists stimulate ciliary cAMP signaling and promote glucagon and insulin secretion by α- and β-cell lines and by mouse and human islets. Transport of GPCRs to primary cilia requires TULP3, whose knockdown in primary human and mouse islets relocalized ciliary FFAR4 and PTGER4 and impaired regulated glucagon or insulin secretion, without affecting ciliary structure. Our findings provide index evidence that regulated hormone secretion by islet α and β cells is controlled by ciliary GPCRs providing new targets for diabetes.
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Affiliation(s)
- Chien-Ting Wu
- Baxter Laboratory, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Keren I Hilgendorf
- Baxter Laboratory, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA
| | - Romina J Bevacqua
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Yan Hang
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Janos Demeter
- Baxter Laboratory, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Seung K Kim
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, California 94305, USA
- Department of Medicine, Stanford University, Stanford, California 94305, USA
| | - Peter K Jackson
- Baxter Laboratory, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, California 94305, USA
- Department of Medicine, Stanford University, Stanford, California 94305, USA
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29
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Wang W, Jack BM, Wang HH, Kavanaugh MA, Maser RL, Tran PV. Intraflagellar Transport Proteins as Regulators of Primary Cilia Length. Front Cell Dev Biol 2021; 9:661350. [PMID: 34095126 PMCID: PMC8170031 DOI: 10.3389/fcell.2021.661350] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/06/2021] [Indexed: 12/21/2022] Open
Abstract
Primary cilia are small, antenna-like organelles that detect and transduce chemical and mechanical cues in the extracellular environment, regulating cell behavior and, in turn, tissue development and homeostasis. Primary cilia are assembled via intraflagellar transport (IFT), which traffics protein cargo bidirectionally along a microtubular axoneme. Ranging from 1 to 10 μm long, these organelles typically reach a characteristic length dependent on cell type, likely for optimum fulfillment of their specific roles. The importance of an optimal cilia length is underscored by the findings that perturbation of cilia length can be observed in a number of cilia-related diseases. Thus, elucidating mechanisms of cilia length regulation is important for understanding the pathobiology of ciliary diseases. Since cilia assembly/disassembly regulate cilia length, we review the roles of IFT in processes that affect cilia assembly/disassembly, including ciliary transport of structural and membrane proteins, ectocytosis, and tubulin posttranslational modification. Additionally, since the environment of a cell influences cilia length, we also review the various stimuli encountered by renal epithelia in healthy and diseased states that alter cilia length and IFT.
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Affiliation(s)
- Wei Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Brittany M Jack
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Henry H Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Matthew A Kavanaugh
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Robin L Maser
- Department of Clinical Laboratory Sciences, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
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30
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Kobayashi T, Ishida Y, Hirano T, Katoh Y, Nakayama K. Cooperation of the IFT-A complex with the IFT-B complex is required for ciliary retrograde protein trafficking and GPCR import. Mol Biol Cell 2021; 32:45-56. [PMID: 33175651 PMCID: PMC8098818 DOI: 10.1091/mbc.e20-08-0556] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/22/2020] [Accepted: 11/03/2020] [Indexed: 12/20/2022] Open
Abstract
Cilia sense and transduce extracellular signals via specific receptors. The intraflagellar transport (IFT) machinery mediates not only bidirectional protein trafficking within cilia but also the import/export of ciliary proteins across the ciliary gate. The IFT machinery is known to comprise two multisubunit complexes, namely, IFT-A and IFT-B; however, little is known about how the two complexes cooperate to mediate ciliary protein trafficking. We here show that IFT144-IFT122 from IFT-A and IFT88-IFT52 from IFT-B make major contributions to the interface between the two complexes. Exogenous expression of the IFT88(Δα) mutant, which has decreased binding to IFT-A, partially restores the ciliogenesis defect of IFT88-knockout (KO) cells. However, IFT88(Δα)-expressing IFT88-KO cells demonstrate a defect in IFT-A entry into cilia, aberrant accumulation of IFT-B proteins at the bulged ciliary tips, and impaired import of ciliary G protein-coupled receptors (GPCRs). Furthermore, overaccumulated IFT proteins at the bulged tips appeared to be released as extracellular vesicles. These phenotypes of IFT88(Δα)-expressing IFT88-KO cells resembled those of IFT144-KO cells. These observations together indicate that the IFT-A complex cooperates with the IFT-B complex to mediate the ciliary entry of GPCRs as well as retrograde trafficking of the IFT machinery from the ciliary tip.
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Affiliation(s)
- Takuya Kobayashi
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Yamato Ishida
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Tomoaki Hirano
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Yohei Katoh
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
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31
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Kerek EM, Yoon KH, Luo SY, Chen J, Valencia R, Julien O, Waskiewicz AJ, Hubbard BP. A conserved acetylation switch enables pharmacological control of tubby-like protein stability. J Biol Chem 2020; 296:100073. [PMID: 33187986 PMCID: PMC7948452 DOI: 10.1074/jbc.ra120.015839] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/30/2020] [Accepted: 11/13/2020] [Indexed: 12/29/2022] Open
Abstract
Tubby-like proteins (TULPs) are characterized by a conserved C-terminal domain that binds phosphoinositides. Collectively, mammalian TULP1-4 proteins play essential roles in intracellular transport, cell differentiation, signaling, and motility. Yet, little is known about how the function of these proteins is regulated in cells. Here, we present the protein–protein interaction network of TULP3, a protein that is responsible for the trafficking of G-protein-coupled receptors to cilia and whose aberrant expression is associated with severe developmental disorders and polycystic kidney disease. We identify several protein interaction nodes linked to TULP3 that include enzymes involved in acetylation and ubiquitination. We show that acetylation of two key lysine residues on TULP3 by p300 increases TULP3 protein abundance and that deacetylation of these sites by HDAC1 decreases protein levels. Furthermore, we show that one of these sites is ubiquitinated in the absence of acetylation and that acetylation inversely correlates with ubiquitination of TULP3. This mechanism is evidently conserved across species and is active in zebrafish during development. Finally, we identify this same regulatory module in TULP1, TULP2, and TULP4 and demonstrate that the stability of these proteins is similarly modulated by an acetylation switch. This study unveils a signaling pathway that links nuclear enzymes to ciliary membrane receptors via TULP3, describes a dynamic mechanism for the regulation of all tubby-like proteins, and explores how to exploit it pharmacologically using drugs.
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Affiliation(s)
- Evan M Kerek
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Kevin H Yoon
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Shu Y Luo
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Jerry Chen
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Robert Valencia
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Olivier Julien
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Andrew J Waskiewicz
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Basil P Hubbard
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada.
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32
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Cells into tubes: Molecular and physical principles underlying lumen formation in tubular organs. Curr Top Dev Biol 2020; 143:37-74. [PMID: 33820625 DOI: 10.1016/bs.ctdb.2020.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tubular networks, such as the vascular and respiratory systems, transport liquids and gases in multicellular organisms. The basic units of these organs are tubes formed by single or multiple cells enclosing a luminal cavity. The formation and maintenance of correctly sized and shaped lumina are fundamental steps in organogenesis and are essential for organismal homeostasis. Therefore, understanding how cells generate, shape and maintain lumina is crucial for understanding normal organogenesis as well as the basis of pathological conditions. Lumen formation involves polarized membrane trafficking, cytoskeletal dynamics, and the influence of intracellular as well as extracellular mechanical forces, such as cortical tension, luminal pressure or blood flow. Various tissue culture and in vivo model systems, ranging from MDCK cell spheroids to tubular organs in worms, flies, fish, and mice, have provided many insights into the molecular and cellular mechanisms underlying lumenogenesis and revealed key factors that regulate the size and shape of cellular tubes. Moreover, the development of new experimental and imaging approaches enabled quantitative analyses of intracellular dynamics and allowed to assess the roles of cellular and tissue mechanics during tubulogenesis. However, how intracellular processes are coordinated and regulated across scales of biological organization to generate properly sized and shaped tubes is only beginning to be understood. Here, we review recent insights into the molecular, cellular and physical mechanisms underlying lumen formation during organogenesis. We discuss how these mechanisms control lumen formation in various model systems, with a special focus on the morphogenesis of tubular organs in Drosophila.
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33
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Hu J, Harris PC. Regulation of polycystin expression, maturation and trafficking. Cell Signal 2020; 72:109630. [PMID: 32275942 PMCID: PMC7269868 DOI: 10.1016/j.cellsig.2020.109630] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/03/2020] [Accepted: 04/04/2020] [Indexed: 12/26/2022]
Abstract
The major autosomal dominant polycystic kidney disease (ADPKD) genes, PKD1 and PKD2, are wildly expressed at the organ and tissue level. PKD1 encodes polycystin 1 (PC1), a large membrane associated receptor-like protein that can complex with the PKD2 product, PC2. Various cellular locations have been described for both PC1, including the plasma membrane and extracellular vesicles, and PC2, especially the endoplasmic reticulum (ER), but compelling evidence indicates that the primary cilium, a sensory organelle, is the key site for the polycystin complex to prevent PKD. As with other membrane proteins, the ER biogenesis pathway is key to appropriately folding, performing quality control, and exporting fully folded PC1 to the Golgi apparatus. There is a requirement for binding with PC2 and cleavage of PC1 at the GPS for this folding and export to occur. Six different monogenic defects in this pathway lead to cystic disease development, with PC1 apparently particularly sensitive to defects in this general protein processing pathway. Trafficking of membrane proteins, and the polycystins in particular, through the Golgi to the primary cilium have been analyzed in detail, but at this time, there is no clear consensus on a ciliary targeting sequence required to export proteins to the cilium. After transitioning though the trans-Golgi network, polycystin-bearing vesicles are likely sorted to early or recycling endosomes and then transported to the ciliary base, possibly via docking to transition fibers (TF). The membrane-bound polycystin complex then undergoes facilitated trafficking through the transition zone, the diffusion barrier at the base of the cilium, before entering the cilium. Intraflagellar transport (IFT) may be involved in moving the polycystins along the cilia, but data also indicates other mechanisms. The ciliary polycystin complex can be ubiquitinated and removed from cilia by internalization at the ciliary base and may be sent back to the plasma membrane for recycling or to lysosomes for degradation. Monogenic defects in processes regulating the protein composition of cilia are associated with syndromic disorders involving many organ systems, reflecting the pleotropic role of cilia during development and for tissue maintenance. Many of these ciliopathies have renal involvement, likely because of faulty polycystin signaling from cilia. Understanding the expression, maturation and trafficking of the polycystins helps understand PKD pathogenesis and suggests opportunities for therapeutic intervention.
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Affiliation(s)
- Jinghua Hu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA; Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
| | - Peter C Harris
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA; Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, USA.
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34
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Legué E, Liem KF. Mutations in Ciliary Trafficking Genes affect Sonic Hedgehog-dependent Neural Tube Patterning Differentially along the Anterior-Posterior Axis. Neuroscience 2020; 450:3-14. [PMID: 32682825 DOI: 10.1016/j.neuroscience.2020.07.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 06/30/2020] [Accepted: 07/10/2020] [Indexed: 12/13/2022]
Abstract
Cell specification in the ventral spinal cord is a well-studied model system to understand how tissue pattern develops in response to a morphogen gradient. Ventral cell types including motor neurons (MNs) are induced in the neural tube in response to graded Sonic Hedgehog (Shh) signaling. We performed a forward genetic screen in the mouse that incorporated a GFP-expressing transgene to visualize MNs to identify genes regulating ventral patterning. Here we contrast the neural patterning phenotypes of two mouse lines carrying induced mutations in ciliary trafficking genes. We show that a hypomorphic mutation in the gene Tubby-like protein 3 (Tulp3) resulted in a dorsal expansion of MNs consistent with an up-regulation of Shh signaling. Interestingly, patterning defects in Tulp3 mutants were restricted to posterior regions of the spinal cord as patterning was similar to WT in the anterior spinal cord. In contrast, a mutation in the ciliary trafficking gene cytoplasmic dynein 2 heavy chain 1 (Dync2h1), led to a complete loss of MNs in anterior regions of the spinal cord, indicating a strong down-regulation of Shh signaling. However, this severe phenotype was restricted to the cervical region as MNs developed posteriorly. Mutations in cilia trafficking genes affect Shh-dependent signaling in the neural tube differentially along the anterior-posterior (A-P) axis in a process that is not understood.
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Affiliation(s)
- Emilie Legué
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06520, United States
| | - Karel F Liem
- Vertebrate Developmental Biology Program, Department of Pediatrics, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06520, United States.
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35
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Gallagher AR, Somlo S. Loss of Cilia Does Not Slow Liver Disease Progression in Mouse Models of Autosomal Recessive Polycystic Kidney Disease. ACTA ACUST UNITED AC 2020; 1:962-968. [PMID: 33829210 DOI: 10.34067/kid.0001022019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Anna Rachel Gallagher
- Department of Internal Medicine (Nephrology), Yale School of Medicine, New Haven, Connecticut
| | - Stefan Somlo
- Department of Internal Medicine (Nephrology), Yale School of Medicine, New Haven, Connecticut.,Department of Genetics, Yale School of Medicine, New Haven, Connecticut
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36
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Cilia and polycystic kidney disease. Semin Cell Dev Biol 2020; 110:139-148. [PMID: 32475690 DOI: 10.1016/j.semcdb.2020.05.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 05/03/2020] [Accepted: 05/03/2020] [Indexed: 11/20/2022]
Abstract
Polycystic kidney disease (PKD), comprising autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD), is characterized by incessant cyst formation in the kidney and liver. ADPKD and ARPKD represent the leading genetic causes of renal disease in adults and children, respectively. ADPKD is caused by mutations in PKD1 encoding polycystin1 (PC1) and PKD2 encoding polycystin 2 (PC2). PC1/2 are multi-pass transmembrane proteins that form a complex localized in the primary cilium. Predominant ARPKD cases are caused by mutations in polycystic kidney and hepatic disease 1 (PKHD1) gene that encodes the Fibrocystin/Polyductin (FPC) protein, whereas a small subset of cases are caused by mutations in DAZ interacting zinc finger protein 1 like (DZIP1L) gene. FPC is a type I transmembrane protein, localizing to the cilium and basal body, in addition to other compartments, and DZIP1L encodes a transition zone/basal body protein. Apparently, PC1/2 and FPC are signaling molecules, while the mechanism that cilia employ to govern renal tubule morphology and prevent cyst formation is unclear. Nonetheless, recent genetic and biochemical studies offer a glimpse of putative physiological malfunctions and the pathomechanisms underlying both disease entities. In this review, I summarize the results of genetic studies that deduced the function of PC1/2 on cilia and of cilia themselves in cyst formation in ADPKD, and I discuss studies regarding regulation of polycystin biogenesis and cilia trafficking. I also summarize the synergistic genetic interactions between Pkd1 and Pkhd1, and the unique tissue patterning event controlled by FPC, but not PC1. Interestingly, while DZIP1L mutations generate compromised PC1/2 cilia expression, FPC deficiency does not affect PC1/2 biogenesis and ciliary localization, indicating that divergent mechanisms could lead to cyst formation in ARPKD. I conclude by outlining promising areas for future PKD research and highlight rationales for potential therapeutic interventions for PKD treatment.
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37
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Ferent J, Constable S, Gigante ED, Yam PT, Mariani LE, Legué E, Liem KF, Caspary T, Charron F. The Ciliary Protein Arl13b Functions Outside of the Primary Cilium in Shh-Mediated Axon Guidance. Cell Rep 2019; 29:3356-3366.e3. [PMID: 31825820 PMCID: PMC6927553 DOI: 10.1016/j.celrep.2019.11.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 09/19/2019] [Accepted: 11/04/2019] [Indexed: 12/19/2022] Open
Abstract
The small GTPase Arl13b is enriched in primary cilia and regulates Sonic hedgehog (Shh) signaling. During neural development, Shh controls patterning and proliferation through a canonical, transcription-dependent pathway that requires the primary cilium. Additionally, Shh controls axon guidance through a non-canonical, transcription-independent pathway whose connection to the primary cilium is unknown. Here we show that inactivation of Arl13b results in defective commissural axon guidance in vivo. In vitro, we demonstrate that Arl13b functions autonomously in neurons for their Shh-dependent guidance response. We detect Arl13b protein in axons and growth cones, far from its well-established ciliary enrichment. To test whether Arl13b plays a non-ciliary function, we used an engineered, cilia-localization-deficient Arl13b variant and found that it was sufficient to mediate Shh axon guidance in vitro and in vivo. Together, these results indicate that, in addition to its ciliary role in canonical Shh signaling, Arl13b plays a cilia-independent role in Shh-mediated axon guidance.
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Affiliation(s)
- Julien Ferent
- Montreal Clinical Research Institute (IRCM), 110 Pine Avenue West, Montreal, QC H2W 1R7, Canada; Department of Neuroscience, University of Montreal, Montreal, QC H3T 1J4, Canada
| | - Sandii Constable
- Department of Human Genetics, 615 Michael St., Suite 301, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Eduardo D Gigante
- Department of Human Genetics, 615 Michael St., Suite 301, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Patricia T Yam
- Montreal Clinical Research Institute (IRCM), 110 Pine Avenue West, Montreal, QC H2W 1R7, Canada
| | - Laura E Mariani
- Department of Human Genetics, 615 Michael St., Suite 301, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Emilie Legué
- Vertebrate Developmental Biology Program and Department of Pediatrics, Yale School of Medicine, 333 Cedar St., New Haven, CT 06520, USA
| | - Karel F Liem
- Vertebrate Developmental Biology Program and Department of Pediatrics, Yale School of Medicine, 333 Cedar St., New Haven, CT 06520, USA
| | - Tamara Caspary
- Department of Human Genetics, 615 Michael St., Suite 301, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Frédéric Charron
- Montreal Clinical Research Institute (IRCM), 110 Pine Avenue West, Montreal, QC H2W 1R7, Canada; Department of Neuroscience, University of Montreal, Montreal, QC H3T 1J4, Canada; Department of Anatomy and Cell Biology, Division of Experimental Medicine, McGill University, Montreal, QC H3A 0G4, Canada; Department of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada.
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38
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Ma M, Legué E, Tian X, Somlo S, Liem KF. Cell-Autonomous Hedgehog Signaling Is Not Required for Cyst Formation in Autosomal Dominant Polycystic Kidney Disease. J Am Soc Nephrol 2019; 30:2103-2111. [PMID: 31451534 DOI: 10.1681/asn.2018121274] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 07/15/2019] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND PKD1 or PKD2, the two main causal genes for autosomal dominant polycystic kidney disease (ADPKD), encode the multipass transmembrane proteins polycystin-1 (PC1) and polycystin-2 (PC2), respectively. Polycystins localize to the primary cilium, an organelle essential for cell signaling, including signal transduction of the Hedgehog pathway. Mutations in ciliary genes that build and maintain the cilium also cause renal cystic disease through unknown pathways. Although recent studies have found alterations in Hedgehog signaling in ADPKD-related models and tissues, the relationship between Hedgehog and polycystic kidney disease is not known. METHODS To examine the potential role of cell-autonomous Hedgehog signaling in regulating kidney cyst formation in vivo in both early- and adult-onset mouse models of ADPKD, we used conditional inactivation of Pkd1 combined with conditional modulation of Hedgehog signaling components in renal epithelial cells, where mutations in Pkd1 initiate cyst formation. After increasing or decreasing levels of Hedgehog signaling in cells that underwent inactivation of Pkd1, we evaluated the effects of these genetic manipulations on quantitative parameters of polycystic kidney disease severity. RESULTS We found that in Pkd1 conditional mutant mouse kidneys, neither downregulation nor activation of the Hedgehog pathway in epithelial cells along the nephron significantly influenced the severity of the polycystic kidney phenotype in mouse models of developmental or adult-onset of ADPKD. CONCLUSIONS These data suggest that loss of Pkd1 function results in kidney cysts through pathways that are not affected by the activity of the Hedgehog pathway.
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Affiliation(s)
- Ming Ma
- Departments of Internal Medicine
| | - Emilie Legué
- Pediatrics, and.,Vertebrate Developmental Biology Program, Yale University, New Haven, Connecticut
| | - Xin Tian
- Departments of Internal Medicine
| | | | - Karel F Liem
- Pediatrics, and .,Vertebrate Developmental Biology Program, Yale University, New Haven, Connecticut
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39
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DiTirro D, Philbrook A, Rubino K, Sengupta P. The Caenorhabditis elegans Tubby homolog dynamically modulates olfactory cilia membrane morphogenesis and phospholipid composition. eLife 2019; 8:48789. [PMID: 31259686 PMCID: PMC6624019 DOI: 10.7554/elife.48789] [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: 05/24/2019] [Accepted: 06/21/2019] [Indexed: 12/13/2022] Open
Abstract
Plasticity in sensory signaling is partly mediated via regulated trafficking of signaling molecules to and from primary cilia. Tubby-related proteins regulate ciliary protein transport; however, their roles in remodeling cilia properties are not fully understood. We find that the C. elegans TUB-1 Tubby homolog regulates membrane morphogenesis and signaling protein transport in specialized sensory cilia. In particular, TUB-1 is essential for sensory signaling-dependent reshaping of olfactory cilia morphology. We show that compromised sensory signaling alters cilia membrane phosphoinositide composition via TUB-1-dependent trafficking of a PIP5 kinase. TUB-1 regulates localization of this lipid kinase at the cilia base in part via localization of the AP-2 adaptor complex subunit DPY-23. Our results describe new functions for Tubby proteins in the dynamic regulation of cilia membrane lipid composition, morphology, and signaling protein content, and suggest that this conserved family of proteins plays a critical role in mediating cilia structural and functional plasticity.
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Affiliation(s)
- Danielle DiTirro
- Department of Biology, Brandeis University, Waltham, United States
| | - Alison Philbrook
- Department of Biology, Brandeis University, Waltham, United States
| | - Kendrick Rubino
- Department of Biology, Brandeis University, Waltham, United States
| | - Piali Sengupta
- Department of Biology, Brandeis University, Waltham, United States
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40
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Hwang SH, Somatilaka BN, Badgandi H, Palicharla VR, Walker R, Shelton JM, Qian F, Mukhopadhyay S. Tulp3 Regulates Renal Cystogenesis by Trafficking of Cystoproteins to Cilia. Curr Biol 2019; 29:790-802.e5. [PMID: 30799239 DOI: 10.1016/j.cub.2019.01.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/09/2018] [Accepted: 01/17/2019] [Indexed: 12/25/2022]
Abstract
Polycystic kidney disease proteins, polycystin-1 and polycystin-2, localize to primary cilia. Polycystin knockouts have severe cystogenesis compared to ciliary disruption, whereas simultaneous ciliary loss suppresses excessive cyst growth. These data suggest the presence of a cystogenic activator that is inhibited by polycystins and an independent but relatively minor cystogenic inhibitor, either of which are cilia dependent. However, current genetic models targeting cilia completely ablate the compartment, making it difficult to uncouple cystoprotein function from ciliary localization. Thus, the role of cilium-generated signaling in cystogenesis is unclear. We recently demonstrated that the tubby family protein Tulp3 determines ciliary trafficking of polycystins in kidney collecting duct cells without affecting protein levels or cilia. Here, we demonstrate that embryonic-stage, nephron-specific Tulp3 knockout mice developed cystic kidneys, while retaining intact cilia. Cystic kidneys showed increased mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), mTOR, and persistently high cyclic AMP (cAMP) signaling, suggesting contribution of multiple factors to cystogenesis. Based on kidney-to-body-weight ratio, cystic index, and epithelial proliferation in developing tubules or cysts, the severity of cystogenesis upon Tulp3 deletion was intermediate between that caused by loss of polycystin-1 or cilia. However, concomitant Tulp3 loss did not inhibit cystogenesis in polycystin-1 knockouts, unlike ciliary disruption. Interestingly, ciliary trafficking of the small guanosine triphosphatase (GTPase) Arl13b, loss of which causes cystogenic severity similar to ciliary loss, was reduced prior to cyst initiation. Thus, we propose that cystogenesis in Tulp3 mutants results from a reduction of ciliary levels of polycystins, Arl13b, and Arl13b-dependent lipidated cargoes. Arl13b might be the ciliary factor that represses cystogenesis distinct from polycystins.
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Affiliation(s)
- Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Bandarigoda N Somatilaka
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Hemant Badgandi
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Vivek Reddy Palicharla
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Rebecca Walker
- Division of Nephrology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - John M Shelton
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Feng Qian
- Division of Nephrology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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