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Han S, Hu Y, Jia D, Lv Y, Liu M, Wang D, Chao J, Xia X, Wang Q, Liu P, Cai Y, Ren X. IFT27 regulates the long-term maintenance of photoreceptor outer segments in zebrafish. Gene 2024; 905:148237. [PMID: 38310983 DOI: 10.1016/j.gene.2024.148237] [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: 11/30/2023] [Revised: 01/22/2024] [Accepted: 01/30/2024] [Indexed: 02/06/2024]
Abstract
Approximately a quarter of Retinitis Pigmentosa (RP) is caused by mutations in transport-related genes in cilia. IFT27 (Intraflagellar Transport 27), a core component of the ciliary intraflagellar transport (IFT) system, has been implicated as a significant pathogenic gene in RP. The pathogenic mechanisms and subsequent pathology related to IFT27 mutations in RP are largely obscure. Here, we utilized TALEN technology to create an ift27 knockout (ift27-/-) zebrafish model. Electroretinography (ERG) detection showed impaired vision in this model. Histopathological examinations disclosed that ift27 mutations cause progressive degeneration of photoreceptors in zebrafish, and this degeneration was late-onset. Immunofluorescence labeling of outer segments showed that rods degenerated before cones, aligning with the conventional characterization of RP. In cultured human retinal pigment epithelial cells, we found that IFT27 was involved in maintaining ciliary morphology. Furthermore, decreased IFT27 expression resulted in the inhibition of the Hedgehog (Hh) signaling pathway, including decreased expression of key factors in the Hh pathway and abnormal localization of the ciliary mediator Gli2. In summary, we generated an ift27-/- zebrafish line with retinal degeneration which mimicked the symptoms of RP patients, highlighting IFT27's integral role in the long-term maintenance of cilia via the Hh signaling pathway. This work may furnish new insights into the treatment or delay of RP caused by IFT27 mutations.
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Affiliation(s)
- Shanshan Han
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China.
| | - Yue Hu
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Danna Jia
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China
| | - Yuexia Lv
- Prenatal Diagnosis Center, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Decheng Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Jin Chao
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Xuan Xia
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Qiong Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Pei Liu
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Yu Cai
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang 443002, Hubei, China; College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, Hubei, China
| | - Xiang Ren
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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2
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Liu J, Xie H, Wu M, Hu Y, Kang Y. The role of cilia during organogenesis in zebrafish. Open Biol 2023; 13:230228. [PMID: 38086423 PMCID: PMC10715920 DOI: 10.1098/rsob.230228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/03/2023] [Indexed: 12/18/2023] Open
Abstract
Cilia are hair-like organelles that protrude from the surface of eukaryotic cells and are present on the surface of nearly all human cells. Cilia play a crucial role in signal transduction, organ development and tissue homeostasis. Abnormalities in the structure and function of cilia can lead to a group of human diseases known as ciliopathies. Currently, zebrafish serves as an ideal model for studying ciliary function and ciliopathies due to its relatively conserved structure and function of cilia compared to humans. In this review, we will summarize the different types of cilia that present in embryonic and adult zebrafish, and provide an overview of the advantages of using zebrafish as a vertebrate model for cilia research. We will specifically focus on the roles of cilia during zebrafish organogenesis based on recent studies. Additionally, we will highlight future prospects for ciliary research in zebrafish.
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Affiliation(s)
- Junjun Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, People's Republic of China
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Haibo Xie
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, People's Republic of China
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Mengfan Wu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, People's Republic of China
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Yidan Hu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, People's Republic of China
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Yunsi Kang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, People's Republic of China
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, People's Republic of China
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3
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Masek M, Bachmann-Gagescu R. Control of protein and lipid composition of photoreceptor outer segments-Implications for retinal disease. Curr Top Dev Biol 2023; 155:165-225. [PMID: 38043951 DOI: 10.1016/bs.ctdb.2023.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Vision is arguably our most important sense, and its loss brings substantial limitations to daily life for affected individuals. Light is perceived in retinal photoreceptors (PRs), which are highly specialized neurons subdivided into several compartments with distinct functions. The outer segments (OSs) of photoreceptors represent highly specialized primary ciliary compartments hosting the phototransduction cascade, which transforms incoming light into a neuronal signal. Retinal disease can result from various pathomechanisms originating in distinct subcompartments of the PR cell, or in the retinal pigment epithelium which supports the PRs. Dysfunction of primary cilia causes human disorders known as "ciliopathies", in which retinal disease is a common feature. This chapter focuses on PR OSs, discussing the mechanisms controlling their complex structure and composition. A sequence of tightly regulated sorting and trafficking events, both upstream of and within this ciliary compartment, ensures the establishment and maintenance of the adequate proteome and lipidome required for signaling in response to light. We discuss in particular our current understanding of the role of ciliopathy proteins involved in multi-protein complexes at the ciliary transition zone (CC2D2A) or BBSome (BBS1) and how their dysfunction causes retinal disease. While the loss of CC2D2A prevents the fusion of vesicles and delivery of the photopigment rhodopsin to the ciliary base, leading to early OS ultrastructural defects, BBS1 deficiency results in precocious accumulation of cholesterol in mutant OSs and decreased visual function preceding morphological changes. These distinct pathomechanisms underscore the central role of ciliary proteins involved in multiple processes controlling OS protein and lipid composition.
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Affiliation(s)
- Markus Masek
- Institute of Medical Genetics, University of Zurich, Zurich, Switzerland; Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Ruxandra Bachmann-Gagescu
- Institute of Medical Genetics, University of Zurich, Zurich, Switzerland; Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland; University Research Priority Program AdaBD, University of Zurich, Zurich, Switzerland.
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4
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Rivera-Colón AG, Rayamajhi N, Minhas BF, Madrigal G, Bilyk KT, Yoon V, Hüne M, Gregory S, Cheng CHC, Catchen JM. Genomics of Secondarily Temperate Adaptation in the Only Non-Antarctic Icefish. Mol Biol Evol 2023; 40:7035026. [PMID: 36806940 PMCID: PMC9985337 DOI: 10.1093/molbev/msad029] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/10/2023] [Accepted: 01/30/2023] [Indexed: 02/23/2023] Open
Abstract
White-blooded Antarctic icefishes, a family within the adaptive radiation of Antarctic notothenioid fishes, are an example of extreme biological specialization to both the chronic cold of the Southern Ocean and life without hemoglobin. As a result, icefishes display derived physiology that limits them to the cold and highly oxygenated Antarctic waters. Against these constraints, remarkably one species, the pike icefish Champsocephalus esox, successfully colonized temperate South American waters. To study the genetic mechanisms underlying secondarily temperate adaptation in icefishes, we generated chromosome-level genome assemblies of both C. esox and its Antarctic sister species, Champsocephalus gunnari. The C. esox genome is similar in structure and organization to that of its Antarctic congener; however, we observe evidence of chromosomal rearrangements coinciding with regions of elevated genetic divergence in pike icefish populations. We also find several key biological pathways under selection, including genes related to mitochondria and vision, highlighting candidates behind temperate adaptation in C. esox. Substantial antifreeze glycoprotein (AFGP) pseudogenization has occurred in the pike icefish, likely due to relaxed selection following ancestral escape from Antarctica. The canonical AFGP locus organization is conserved in C. esox and C. gunnari, but both show a translocation of two AFGP copies to a separate locus, previously unobserved in cryonotothenioids. Altogether, the study of this secondarily temperate species provides an insight into the mechanisms underlying adaptation to ecologically disparate environments in this otherwise highly specialized group.
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Affiliation(s)
- Angel G Rivera-Colón
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Niraj Rayamajhi
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
| | | | - Giovanni Madrigal
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Kevin T Bilyk
- Department of Biology, Montclair State University, Montclair, NJ
| | - Veronica Yoon
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Mathias Hüne
- Centro de Investigación para la Conservación de los Ecosistemas Australes, Punta Arenas, Chile
| | - Susan Gregory
- British Antarctic Survey, Cambridge, United Kingdom.,Government of South Georgia and the South Sandwich Islands, Stanley, Falklands
| | - C H Christina Cheng
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
| | - Julian M Catchen
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL
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5
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Life-Saver or Undertaker: The Relationship between Primary Cilia and Cell Death in Vertebrate Embryonic Development. J Dev Biol 2022; 10:jdb10040052. [PMID: 36547474 PMCID: PMC9783631 DOI: 10.3390/jdb10040052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 12/02/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
The development of multicellular organisms requires a tightly coordinated network of cellular processes and intercellular signalling. For more than 20 years, it has been known that primary cilia are deeply involved in the mediation of intercellular signalling and that ciliary dysfunction results in severe developmental defects. Cilia-mediated signalling regulates cellular processes such as proliferation, differentiation, migration, etc. Another cellular process ensuring proper embryonic development is cell death. While the effect of cilia-mediated signalling on many cellular processes has been extensively studied, the relationship between primary cilia and cell death remains largely unknown. This article provides a short review on the current knowledge about this relationship.
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6
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Wang J, Thomas HR, Thompson RG, Waldrep SC, Fogerty J, Song P, Li Z, Ma Y, Santra P, Hoover JD, Yeo NC, Drummond IA, Yoder BK, Amack JD, Perkins B, Parant JM. Variable phenotypes and penetrance between and within different zebrafish ciliary transition zone mutants. Dis Model Mech 2022; 15:dmm049568. [PMID: 36533556 PMCID: PMC9844136 DOI: 10.1242/dmm.049568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 11/04/2022] [Indexed: 12/23/2022] Open
Abstract
Meckel syndrome, nephronophthisis, Joubert syndrome and Bardet-Biedl syndrome are caused by mutations in proteins that localize to the ciliary transition zone (TZ). The phenotypically distinct syndromes suggest that these TZ proteins have differing functions. However, mutations in a single TZ gene can result in multiple syndromes, suggesting that the phenotype is influenced by modifier genes. We performed a comprehensive analysis of ten zebrafish TZ mutants, including mks1, tmem216, tmem67, rpgrip1l, cc2d2a, b9d2, cep290, tctn1, nphp1 and nphp4, as well as mutants in ift88 and ift172. Our data indicate that variations in phenotypes exist between different TZ mutants, supporting different tissue-specific functions of these TZ genes. Further, we observed phenotypic variations within progeny of a single TZ mutant, reminiscent of multiple disease syndromes being associated with mutations in one gene. In some mutants, the dynamics of the phenotype became complex with transitory phenotypes that are corrected over time. We also demonstrated that multiple-guide-derived CRISPR/Cas9 F0 'crispant' embryos recapitulate zygotic null phenotypes, and rapidly identified ciliary phenotypes in 11 cilia-associated gene candidates (ankfn1, ccdc65, cfap57, fhad1, nme7, pacrg, saxo2, c1orf194, ttc26, zmynd12 and cfap52).
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Affiliation(s)
- Jun Wang
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Holly R. Thomas
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Robert G. Thompson
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Stephanie C. Waldrep
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Joseph Fogerty
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Ping Song
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Zhang Li
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, AL 35294, USA
| | - Yongjie Ma
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Peu Santra
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Jonathan D. Hoover
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Nan Cher Yeo
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
| | - Iain A. Drummond
- Davis Center for Aging and Regeneration, Mount Desert Island Biological Laboratory, 159 Old Bar Harbor Road, Bar Harbor, ME 04609, USA
| | - Bradley K. Yoder
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, AL 35294, USA
| | - Jeffrey D. Amack
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Brian Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH 44106, USA
| | - John M. Parant
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294, USA
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Specialization of the photoreceptor transcriptome by Srrm3-dependent microexons is required for outer segment maintenance and vision. Proc Natl Acad Sci U S A 2022; 119:e2117090119. [PMID: 35858306 PMCID: PMC9303857 DOI: 10.1073/pnas.2117090119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Retinal photoreceptors have a distinct transcriptomic profile compared to other neuronal subtypes, likely reflecting their unique cellular morphology and function in the detection of light stimuli by way of the ciliary outer segment. We discovered a layer of this molecular specialization by revealing that the vertebrate retina expresses the largest number of tissue-enriched microexons of all tissue types. A subset of these microexons is included exclusively in photoreceptor transcripts, particularly in genes involved in cilia biogenesis and vesicle-mediated transport. This microexon program is regulated by Srrm3, a paralog of the neural microexon regulator Srrm4. Despite the fact that both proteins positively regulate retina microexons in vitro, only Srrm3 is highly expressed in mature photoreceptors. Its deletion in zebrafish results in widespread down-regulation of microexon inclusion from early developmental stages, followed by other transcriptomic alterations, severe photoreceptor defects, and blindness. These results shed light on the transcriptomic specialization and functionality of photoreceptors, uncovering unique cell type-specific roles for Srrm3 and microexons with implications for retinal diseases.
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Zebrafish and inherited photoreceptor disease: Models and insights. Prog Retin Eye Res 2022; 91:101096. [PMID: 35811244 DOI: 10.1016/j.preteyeres.2022.101096] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/20/2022] [Accepted: 06/23/2022] [Indexed: 11/21/2022]
Abstract
Photoreceptor dysfunctions and degenerative diseases are significant causes of vision loss in patients, with few effective treatments available. Targeted interventions to prevent or reverse photoreceptor-related vision loss are not possible without a thorough understanding of the underlying mechanism leading to disease, which is exceedingly difficult to accomplish in the human system. Cone diseases are particularly challenging to model, as some popular genetically modifiable model animals are nocturnal with a rod-dominant visual system and cones that have dissimilarities to human cones. As a result, cone diseases, which affect visual acuity, colour perception, and central vision in patients, are generally poorly understood in terms of pathology and mechanism. Zebrafish (Danio rerio) provide the opportunity to model photoreceptor diseases in a diurnal vertebrate with a cone-rich retina which develops many macular degeneration-like pathologies. Zebrafish undergo external development, allowing early-onset retinal diseases to be detected and studied, and many ophthalmic tools are available for zebrafish visual assessment during development and adulthood. There are numerous zebrafish models of photoreceptor disease, spanning the various types of photoreceptor disease (developmental, rod, cone, and mixed photoreceptor diseases) and genetic/molecular cause. In this review, we explore the features of zebrafish that make them uniquely poised to model cone diseases, summarize the established zebrafish models of inherited photoreceptor disease, and discuss how disease in these models compares to the human presentation, where applicable. Further, we highlight the contributions of these zebrafish models to our understanding of photoreceptor biology and disease, and discuss future directions for utilising and investigating these diverse models.
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Rusterholz TDS, Hofmann C, Bachmann-Gagescu R. Insights Gained From Zebrafish Models for the Ciliopathy Joubert Syndrome. Front Genet 2022; 13:939527. [PMID: 35846153 PMCID: PMC9280682 DOI: 10.3389/fgene.2022.939527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 05/26/2022] [Indexed: 12/04/2022] Open
Abstract
Cilia are quasi-ubiquitous microtubule-based sensory organelles, which play vital roles in signal transduction during development and cell homeostasis. Dysfunction of cilia leads to a group of Mendelian disorders called ciliopathies, divided into different diagnoses according to clinical phenotype constellation and genetic causes. Joubert syndrome (JBTS) is a prototypical ciliopathy defined by a diagnostic cerebellar and brain stem malformation termed the “Molar Tooth Sign” (MTS), in addition to which patients display variable combinations of typical ciliopathy phenotypes such as retinal dystrophy, fibrocystic renal disease, polydactyly or skeletal dystrophy. Like most ciliopathies, JBTS is genetically highly heterogeneous with ∼40 associated genes. Zebrafish are widely used to model ciliopathies given the high conservation of ciliary genes and the variety of specialized cilia types similar to humans. In this review, we compare different existing JBTS zebrafish models with each other and describe their contributions to our understanding of JBTS pathomechanism. We find that retinal dystrophy, which is the most investigated ciliopathy phenotype in zebrafish ciliopathy models, is caused by distinct mechanisms according to the affected gene. Beyond this, differences in phenotypes in other organs observed between different JBTS-mutant models suggest tissue-specific roles for proteins implicated in JBTS. Unfortunately, the lack of systematic assessment of ciliopathy phenotypes in the mutants described in the literature currently limits the conclusions that can be drawn from these comparisons. In the future, the numerous existing JBTS zebrafish models represent a valuable resource that can be leveraged in order to gain further insights into ciliary function, pathomechanisms underlying ciliopathy phenotypes and to develop treatment strategies using small molecules.
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Affiliation(s)
- Tamara D. S. Rusterholz
- Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
- Department of Molecular Life Sciences, University of Zurich, Zürich, Switzerland
| | - Claudia Hofmann
- Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
- Department of Molecular Life Sciences, University of Zurich, Zürich, Switzerland
| | - Ruxandra Bachmann-Gagescu
- Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
- Department of Molecular Life Sciences, University of Zurich, Zürich, Switzerland
- *Correspondence: Ruxandra Bachmann-Gagescu,
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Radhakrishnan R, Dronamraju VR, Leung M, Gruesen A, Solanki AK, Walterhouse S, Roehrich H, Song G, da Costa Monsanto R, Cureoglu S, Martin R, Kondkar AA, van Kuijk FJ, Montezuma SR, Knöelker HJ, Hufnagel RB, Lobo GP. The role of motor proteins in photoreceptor protein transport and visual function. Ophthalmic Genet 2022; 43:285-300. [PMID: 35470760 DOI: 10.1080/13816810.2022.2062391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Rods and cones are photoreceptor neurons in the retina that are required for visual sensation in vertebrates, wherein the perception of vision is initiated when these neurons respond to photons in the light stimuli. The photoreceptor cell is structurally studied as outer segments (OS) and inner segments (IS) where proper protein sorting, localization, and compartmentalization are critical for phototransduction, visual function, and survival. In human retinal diseases, improper protein transport to the OS or mislocalization of proteins to the IS and other cellular compartments could lead to impaired visual responses and photoreceptor cell degeneration that ultimately cause loss of visual function. RESULTS Therefore, studying and identifying mechanisms involved in facilitating and maintaining proper protein transport in photoreceptor cells would help our understanding of pathologies involving retinal cell degeneration in inherited retinal dystrophies, age-related macular degeneration, and Usher Syndrome. CONCLUSIONS Our mini-review will discuss mechanisms of protein transport within photoreceptors and introduce a novel role for an unconventional motor protein, MYO1C, in actin-based motor transport of the visual chromophore Rhodopsin to the OS, in support of phototransduction and visual function.
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Affiliation(s)
- Rakesh Radhakrishnan
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Venkateshwara R Dronamraju
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Matthias Leung
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Andrew Gruesen
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Ashish K Solanki
- Department of Medicine, Drug Discovery Building, Medical University of South Carolina, South Carolina, USA
| | - Stephen Walterhouse
- Department of Medicine, Drug Discovery Building, Medical University of South Carolina, South Carolina, USA
| | - Heidi Roehrich
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Grace Song
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Rafael da Costa Monsanto
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Sebahattin Cureoglu
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - René Martin
- Faculty of Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Altaf A Kondkar
- Department of Ophthalmology.,Glaucoma Research Chair in Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Frederik J van Kuijk
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Sandra R Montezuma
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA
| | | | - Robert B Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Glenn P Lobo
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota, USA.,Department of Medicine, Drug Discovery Building, Medical University of South Carolina, South Carolina, USA.,Department of Ophthalmology, Medical University of South Carolina, South Carolina, USA
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11
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Miles A, Blair C, Emili A, Tropepe V. Usher syndrome type 1-associated gene, pcdh15b, is required for photoreceptor structural integrity in zebrafish. Dis Model Mech 2021; 14:272551. [PMID: 34668518 PMCID: PMC8669488 DOI: 10.1242/dmm.048965] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 10/13/2021] [Indexed: 12/23/2022] Open
Abstract
Blindness associated with Usher syndrome type 1 (USH1) is typically characterized as rod photoreceptor degeneration, followed by secondary loss of cones. The mechanisms leading to blindness are unknown because most genetic mouse models only recapitulate auditory defects. We generated zebrafish mutants for one of the USH1 genes, protocadherin-15b (pcdh15b), a putative cell adhesion molecule. Zebrafish Pcdh15 is expressed exclusively in photoreceptors within calyceal processes (CPs), at the base of the outer segment (OS) and within the synapse. In our mutants, rod and cone photoreceptor integrity is compromised, with early and progressively worsening abnormal OS disc growth and detachment, in part due to weakening CP contacts. These effects were attenuated or exacerbated by growth in dark and bright-light conditions, respectively. We also describe novel evidence for structural defects in synapses of pcdh15b mutant photoreceptors. Cell death does not accompany these defects at early stages, suggesting that photoreceptor structural defects, rather than overt cell loss, may underlie vision deficits. Thus, we present the first genetic animal model of a PCDH15-associated retinopathy that can be used to understand the aetiology of blindness in USH1. This article has an associated First Person interview with the first author of the paper. Summary: We present one of the first genetic animal mutants for PCDH15 that displays a severe, early retinopathy and suggests that zebrafish could be a useful model for PCDH15-associated retinal phenotypes.
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Affiliation(s)
- Amanda Miles
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Clarke Blair
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Andrew Emili
- Center for Network Systems Biology, Boston University, Boston, MA 02118, USA
| | - Vincent Tropepe
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
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12
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Zhu P, Xu J, Wang Y, Zhao C. Loss of Ift74 Leads to Slow Photoreceptor Degeneration and Ciliogenesis Defects in Zebrafish. Int J Mol Sci 2021; 22:ijms22179329. [PMID: 34502236 PMCID: PMC8431285 DOI: 10.3390/ijms22179329] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 08/23/2021] [Accepted: 08/23/2021] [Indexed: 12/18/2022] Open
Abstract
Cilia are microtubule-based structures projecting from the cell surface that perform diverse biological functions. Ciliary defects can cause a wide range of genetic disorders known collectively as ciliopathies. Intraflagellar transport (IFT) proteins are essential for the assembly and maintenance of cilia by transporting proteins along the axoneme. Here, we report a lack of Ift74, a core IFT-B protein, leading to ciliogenesis defects in multiple organs during early zebrafish development. Unlike rapid photoreceptor cell death in other ift-b mutants, the photoreceptors of ift74 mutants exhibited a slow degeneration process. Further experiments demonstrated that the connecting cilia of ift74 mutants were initially formed but failed to maintain, which resulted in slow opsin transport efficiency and eventually led to photoreceptor cell death. We also showed that the large amount of maternal ift74 transcripts deposited in zebrafish eggs account for the main reason of slow photoreceptor degeneration in the mutants. Together, our data suggested Ift74 is critical for ciliogenesis and that Ift proteins play variable roles in different types of cilia during early zebrafish development. To our knowledge, this is the first study to show ift-b mutant that displays slow photoreceptor degeneration in zebrafish.
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Affiliation(s)
- Panpan Zhu
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; (P.Z.); (J.X.); (Y.W.)
| | - Jingjin Xu
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; (P.Z.); (J.X.); (Y.W.)
| | - Yadong Wang
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; (P.Z.); (J.X.); (Y.W.)
| | - Chengtian Zhao
- Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; (P.Z.); (J.X.); (Y.W.)
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
- Sars-Fang Centre, Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
- Correspondence:
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13
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Hong Y, Luo Y. Zebrafish Model in Ophthalmology to Study Disease Mechanism and Drug Discovery. Pharmaceuticals (Basel) 2021; 14:ph14080716. [PMID: 34451814 PMCID: PMC8400593 DOI: 10.3390/ph14080716] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/14/2022] Open
Abstract
Visual impairment and blindness are common and seriously affect people’s work and quality of life in the world. Therefore, the effective therapies for eye diseases are of high priority. Zebrafish (Danio rerio) is an alternative vertebrate model as a useful tool for the mechanism elucidation and drug discovery of various eye disorders, such as cataracts, glaucoma, diabetic retinopathy, age-related macular degeneration, photoreceptor degeneration, etc. The genetic and embryonic accessibility of zebrafish in combination with a behavioral assessment of visual function has made it a very popular model in ophthalmology. Zebrafish has also been widely used in ocular drug discovery, such as the screening of new anti-angiogenic compounds or neuroprotective drugs, and the oculotoxicity test. In this review, we summarized the applications of zebrafish as the models of eye disorders to study disease mechanism and investigate novel drug treatments.
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Affiliation(s)
| | - Yan Luo
- Correspondence: ; Tel.: +86-020-87335931
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14
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Zhang S, Liu Y, Huang Q, Yuan S, Liu H, Shi L, Yap YT, Li W, Zhen J, Zhang L, Hess RA, Zhang Z. Murine germ cell-specific disruption of Ift172 causes defects in spermiogenesis and male fertility. Reproduction 2021; 159:409-421. [PMID: 31958312 DOI: 10.1530/rep-17-0789] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 01/20/2020] [Indexed: 01/21/2023]
Abstract
Intraflagellar transport (IFT) is a conserved mechanism essential for the assembly and maintenance of most eukaryotic cilia and flagella. IFT172 is a component of the IFT complex. Global disruption of mouse Ift172 gene caused typical phenotypes of ciliopathy. Mouse Ift172 gene appears to translate two major proteins; the full-length protein is highly expressed in the tissues enriched in cilia and the smaller 130 kDa one is only abundant in the testis. In male germ cells, IFT172 is highly expressed in the manchette of elongating spermatids. A germ cell-specific Ift172 mutant mice were generated, and the mutant mice did not show gross abnormalities. There was no difference in testis/body weight between the control and mutant mice, but more than half of the adult homozygous mutant males were infertile and associated with abnormally developed germ cells in the spermiogenesis phase. The cauda epididymides in mutant mice contained less developed sperm that showed significantly reduced motility, and these sperm had multiple defects in ultrastructure and bent tails. In the mutant mice, testicular expression levels of some IFT components, including IFT20, IFT27, IFT74, IFT81 and IFT140, and a central apparatus protein SPAG16L were not changed. However, expression levels of ODF2, a component of the outer dense fiber, and AKAP4, a component of fibrous sheath, and two IFT components IFT25 and IFT57 were dramatically reduced. Our findings demonstrate that IFT172 is essential for normal male fertility and spermiogenesis in mice, probably by modulating specific IFT proteins and transporting/assembling unique accessory structural proteins into spermatozoa.
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Affiliation(s)
- Shiyang Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Yunhao Liu
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Qian Huang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Shuo Yuan
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Hong Liu
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Lin Shi
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Yi Tian Yap
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Wei Li
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Jingkai Zhen
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Ling Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, USA
| | - Zhibing Zhang
- Department of Physiology, Wayne State University, Detroit, Michigan, USA.,Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA
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15
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Sánchez-Bellver L, Toulis V, Marfany G. On the Wrong Track: Alterations of Ciliary Transport in Inherited Retinal Dystrophies. Front Cell Dev Biol 2021; 9:623734. [PMID: 33748110 PMCID: PMC7973215 DOI: 10.3389/fcell.2021.623734] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/09/2021] [Indexed: 01/14/2023] Open
Abstract
Ciliopathies are a group of heterogeneous inherited disorders associated with dysfunction of the cilium, a ubiquitous microtubule-based organelle involved in a broad range of cellular functions. Most ciliopathies are syndromic, since several organs whose cells produce a cilium, such as the retina, cochlea or kidney, are affected by mutations in ciliary-related genes. In the retina, photoreceptor cells present a highly specialized neurosensory cilium, the outer segment, stacked with membranous disks where photoreception and phototransduction occurs. The daily renewal of the more distal disks is a unique characteristic of photoreceptor outer segments, resulting in an elevated protein demand. All components necessary for outer segment formation, maintenance and function have to be transported from the photoreceptor inner segment, where synthesis occurs, to the cilium. Therefore, efficient transport of selected proteins is critical for photoreceptor ciliogenesis and function, and any alteration in either cargo delivery to the cilium or intraciliary trafficking compromises photoreceptor survival and leads to retinal degeneration. To date, mutations in more than 100 ciliary genes have been associated with retinal dystrophies, accounting for almost 25% of these inherited rare diseases. Interestingly, not all mutations in ciliary genes that cause retinal degeneration are also involved in pleiotropic pathologies in other ciliated organs. Depending on the mutation, the same gene can cause syndromic or non-syndromic retinopathies, thus emphasizing the highly refined specialization of the photoreceptor neurosensory cilia, and raising the possibility of photoreceptor-specific molecular mechanisms underlying common ciliary functions such as ciliary transport. In this review, we will focus on ciliary transport in photoreceptor cells and discuss the molecular complexity underpinning retinal ciliopathies, with a special emphasis on ciliary genes that, when mutated, cause either syndromic or non-syndromic retinal ciliopathies.
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Affiliation(s)
- Laura Sánchez-Bellver
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- Institute of Biomedicine (IBUB-IRSJD), Universitat de Barcelona, Barcelona, Spain
| | - Vasileios Toulis
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- CIBERER, ISCIII, Universitat de Barcelona, Barcelona, Spain
| | - Gemma Marfany
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona, Spain
- Institute of Biomedicine (IBUB-IRSJD), Universitat de Barcelona, Barcelona, Spain
- CIBERER, ISCIII, Universitat de Barcelona, Barcelona, Spain
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16
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Noel NCL, MacDonald IM, Allison WT. Zebrafish Models of Photoreceptor Dysfunction and Degeneration. Biomolecules 2021; 11:78. [PMID: 33435268 PMCID: PMC7828047 DOI: 10.3390/biom11010078] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/02/2021] [Accepted: 01/04/2021] [Indexed: 12/15/2022] Open
Abstract
Zebrafish are an instrumental system for the generation of photoreceptor degeneration models, which can be utilized to determine underlying causes of photoreceptor dysfunction and death, and for the analysis of potential therapeutic compounds, as well as the characterization of regenerative responses. We review the wealth of information from existing zebrafish models of photoreceptor disease, specifically as they relate to currently accepted taxonomic classes of human rod and cone disease. We also highlight that rich, detailed information can be derived from studying photoreceptor development, structure, and function, including behavioural assessments and in vivo imaging of zebrafish. Zebrafish models are available for a diversity of photoreceptor diseases, including cone dystrophies, which are challenging to recapitulate in nocturnal mammalian systems. Newly discovered models of photoreceptor disease and drusenoid deposit formation may not only provide important insights into pathogenesis of disease, but also potential therapeutic approaches. Zebrafish have already shown their use in providing pre-clinical data prior to testing genetic therapies in clinical trials, such as antisense oligonucleotide therapy for Usher syndrome.
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Affiliation(s)
- Nicole C. L. Noel
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada; (I.M.M.); (W.T.A.)
| | - Ian M. MacDonald
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada; (I.M.M.); (W.T.A.)
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, AB T6G 2R7, Canada
| | - W. Ted Allison
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada; (I.M.M.); (W.T.A.)
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
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17
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Vig A, Poulter JA, Ottaviani D, Tavares E, Toropova K, Tracewska AM, Mollica A, Kang J, Kehelwathugoda O, Paton T, Maynes JT, Wheway G, Arno G, Khan KN, McKibbin M, Toomes C, Ali M, Di Scipio M, Li S, Ellingford J, Black G, Webster A, Rydzanicz M, Stawiński P, Płoski R, Vincent A, Cheetham ME, Inglehearn CF, Roberts A, Heon E. DYNC2H1 hypomorphic or retina-predominant variants cause nonsyndromic retinal degeneration. Genet Med 2020; 22:2041-2051. [PMID: 32753734 PMCID: PMC7708302 DOI: 10.1038/s41436-020-0915-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 07/16/2020] [Accepted: 07/16/2020] [Indexed: 01/02/2023] Open
Abstract
PURPOSE Determining the role of DYNC2H1 variants in nonsyndromic inherited retinal disease (IRD). METHODS Genome and exome sequencing were performed for five unrelated cases of IRD with no identified variant. In vitro assays were developed to validate the variants identified (fibroblast assay, induced pluripotent stem cell [iPSC] derived retinal organoids, and a dynein motility assay). RESULTS Four novel DYNC2H1 variants (V1, g.103327020_103327021dup; V2, g.103055779A>T; V3, g.103112272C>G; V4, g.103070104A>C) and one previously reported variant (V5, g.103339363T>G) were identified. In proband 1 (V1/V2), V1 was predicted to introduce a premature termination codon (PTC), whereas V2 disrupted the exon 41 splice donor site causing incomplete skipping of exon 41. V1 and V2 impaired dynein-2 motility in vitro and perturbed IFT88 distribution within cilia. V3, homozygous in probands 2-4, is predicted to cause a PTC in a retina-predominant transcript. Analysis of retinal organoids showed that this new transcript expression increased with organoid differentiation. V4, a novel missense variant, was in trans with V5, previously associated with Jeune asphyxiating thoracic dystrophy (JATD). CONCLUSION The DYNC2H1 variants discussed herein were either hypomorphic or affecting a retina-predominant transcript and caused nonsyndromic IRD. Dynein variants, specifically DYNC2H1 variants are reported as a cause of non syndromic IRD.
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Affiliation(s)
- Anjali Vig
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Science, The University of Toronto, Toronto, Canada
| | - James A Poulter
- Department of Ophthalmology, St James' University Hospital, Leeds, UK
| | | | - Erika Tavares
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Katerina Toropova
- Department of Biological Sciences, Birbeck, University of London, London, UK
| | - Anna Maria Tracewska
- DNA Analysis Unit, ŁUKASIEWICZ Research Network-PORT Polish Center for Technology Development, Wrocław, Poland
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Antonio Mollica
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Jasmine Kang
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | | | - Tara Paton
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
- The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Canada
| | - Jason T Maynes
- Department of Anesthesia and Pain Medicine, The Hospital for Sick Children, Toronto, Canada
| | | | - Gavin Arno
- UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital, London, UK
| | - Kamron N Khan
- Department of Ophthalmology, St James' University Hospital, Leeds, UK
| | - Martin McKibbin
- Department of Ophthalmology, St James' University Hospital, Leeds, UK
| | - Carmel Toomes
- Department of Ophthalmology, St James' University Hospital, Leeds, UK
| | - Manir Ali
- Department of Ophthalmology, St James' University Hospital, Leeds, UK
| | - Matteo Di Scipio
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Shuning Li
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Jamie Ellingford
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicines and health, The University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
| | - Graeme Black
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicines and health, The University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Andrew Webster
- UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital, London, UK
| | | | - Piotr Stawiński
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Rafał Płoski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Ajoy Vincent
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Science, The University of Toronto, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | | | | | - Anthony Roberts
- Department of Biological Sciences, Birbeck, University of London, London, UK.
| | - Elise Heon
- Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada.
- Institute of Medical Science, The University of Toronto, Toronto, Canada.
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada.
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18
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Review: Intraflagellar transport proteins in the retina. Mol Vis 2020; 26:652-660. [PMID: 33088169 PMCID: PMC7553723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 10/02/2020] [Indexed: 10/28/2022] Open
Abstract
Intraflagellar transport (IFT) is an essential process in all organisms that serves to move proteins along flagella or cilia in either direction. IFT is performed by IFT particles, which are multiprotein complexes organized into two subcomplexes, A and B. The IFT proteins form interactions with each other, with cargo proteins, and with membranes during the transport process. Several IFT proteins are expressed in many parts of the retina, such as the outer plexiform and outer nuclear layers, and function in the transport of photoreceptor proteins between the inner and outer segments. Mutants of IFT protein genes have been characterized in model organisms such as Chlamydomonas, C. elegans, zebrafish, and the mouse. These mutants have defective ciliogenesis or abnormalities in retinal photoreceptors. Mutations in IFT genes are associated with syndromic and non-syndromic forms of retinal disease in humans, frequently with early onset of disease.
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19
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Pollock LM, Perkins B, Anand-Apte B. Primary cilia are present on endothelial cells of the hyaloid vasculature but are not required for the development of the blood-retinal barrier. PLoS One 2020; 15:e0225351. [PMID: 32735563 PMCID: PMC7394433 DOI: 10.1371/journal.pone.0225351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 07/14/2020] [Indexed: 11/18/2022] Open
Abstract
Endothelial cilia are found in a variety of tissues including the cranial vasculature of zebrafish embryos. Recently, endothelial cells in the developing mouse retina were reported to also possess primary cilia that are potentially involved in vascular remodeling. Fish carrying mutations in intraflagellar transport (ift) genes have disrupted cilia and have been reported to have an increased rate of spontaneous intracranial hemorrhage (ICH), potentially due to disruption of the sonic hedgehog (shh) signaling pathway. However, it remains unknown whether the endothelial cells forming the retinal microvasculature in zebrafish also possess cilia, and whether endothelial cilia are necessary for development and maintenance of the blood-retinal barrier (BRB). In the present study, we found that the endothelial cells lining the zebrafish hyaloid vasculature possess primary cilia during development. To determine whether endothelial cilia are necessary for BRB integrity, ift57, ift88, and ift172 mutants, which lack cilia, were crossed with the double-transgenic zebrafish strain Tg(l-fabp:DBP-EGFP;flk1:mCherry). This strain expresses a vitamin D-binding protein (DBP) fused to enhanced green fluorescent protein (EGFP) as a tracer in the blood plasma, while the endothelial cells forming the vasculature are tagged by mCherry. The Ift mutant fish develop a functional BRB, indicating that endothelial cilia are not necessary for early BRB integrity. Additionally, although treatment of zebrafish larvae with Shh inhibitor cyclopamine results in BRB breakdown, the Ift mutant fish were not sensitized to cyclopamine-induced BRB breakdown.
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Affiliation(s)
- Lana M. Pollock
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States of America
| | - Brian Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States of America
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States of America
| | - Bela Anand-Apte
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States of America
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, United States of America
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20
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Tsai IC, Adams KA, Tzeng JA, Shennib O, Tan PL, Katsanis N. Genome-wide suppressor screen identifies USP35/USP38 as therapeutic candidates for ciliopathies. JCI Insight 2019; 4:130516. [PMID: 31723061 DOI: 10.1172/jci.insight.130516] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/09/2019] [Indexed: 12/17/2022] Open
Abstract
The ciliopathies are a group of phenotypically overlapping disorders caused by structural or functional defects in the primary cilium. Although disruption of numerous signaling pathways and cellular trafficking events have been implicated in ciliary pathology, treatment options for affected individuals remain limited. Here, we performed a genome-wide RNAi (RNA interference) screen to identify genetic suppressors of BBS4, one of the genes mutated in Bardet-Biedl syndrome (BBS). We discovered 10 genes that, when silenced, ameliorate BBS4-dependent pathology. One of these encodes USP35, a negative regulator of the ubiquitin proteasome system, suggesting that inhibition of a deubiquitinase, and subsequent facilitation of the clearance of signaling components, might ameliorate BBS-relevant phenotypes. Testing of this hypothesis in transient and stable zebrafish genetic models showed this posit to be true; suppression or ablation of usp35 ameliorated hallmark ciliopathy defects including impaired convergent extension (CE), renal tubule convolution, and retinal degeneration with concomitant clearance of effectors such as β-catenin and rhodopsin. Together, our findings reinforce a direct link between proteasome-dependent degradation and ciliopathies and suggest that augmentation of this system might offer a rational path to novel therapeutic modalities.
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Affiliation(s)
- I-Chun Tsai
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA
| | - Kevin A Adams
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA
| | - Joyce A Tzeng
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA
| | - Omar Shennib
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA
| | - Perciliz L Tan
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA.,Rescindo Therapeutics, Durham, North Carolina, USA
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina, USA.,Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA.,Departments of Pediatrics and Cellular and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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21
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Hu R, Huang W, Liu J, Jin M, Wu Y, Li J, Wang J, Yu Z, Wang H, Cao Y. Mutagenesis of putative ciliary genes with the CRISPR/Cas9 system in zebrafish identifies genes required for retinal development. FASEB J 2019; 33:5248-5256. [PMID: 30624971 DOI: 10.1096/fj.201802140r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cilia are conserved microtubule-based organelles that function as mechanical and chemical sensors in various cell types. By bioinformatic, genomic, and proteomic studies, more than 2000 proteins have been identified as cilium-associated proteins or putative ciliary proteins; these proteins are referred to as the ciliary proteome or the ciliome. However, little is known about the function of these numerous putative ciliary proteins in cilia. To identify the possible new functional proteins or pathways in cilia, we carried out a small-scale genetic screen targeting 54 putative ciliary genes by using the clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system. We successfully constructed 54 zebrafish mutants, and 8 of them displayed microphthalmias. Three of these 8 genes encode proteins for protein transport, suggesting the important roles of protein transport in retinal development. In situ hybridization revealed that all these genes are expressed in zebrafish eyes. Furthermore, polo-like kinase 1 was required for ciliogenesis in neural tube. We uncovered the potential function of the ciliary genes for the retinal development of zebrafish.-Hu, R., Huang, W., Liu, J., Jin, M., Wu, Y., Li, J., Wang, J., Yu, Z., Wang, H., Cao, Y. Mutagenesis of putative ciliary genes with the CRISPR/Cas9 system in zebrafish identifies genes required for retinal development.
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Affiliation(s)
- Ruikun Hu
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Weilai Huang
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jiangfang Liu
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Miaomiao Jin
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Yue Wu
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jingyu Li
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jingyi Wang
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Zehao Yu
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Hong Wang
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Ying Cao
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
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Pandey G, Westhoff JH, Schaefer F, Gehrig J. A Smart Imaging Workflow for Organ-Specific Screening in a Cystic Kidney Zebrafish Disease Model. Int J Mol Sci 2019; 20:ijms20061290. [PMID: 30875791 PMCID: PMC6471943 DOI: 10.3390/ijms20061290] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 02/25/2019] [Accepted: 03/10/2019] [Indexed: 12/19/2022] Open
Abstract
The zebrafish is being increasingly used in biomedical research and drug discovery to conduct large-scale compound screening. However, there is a lack of accessible methodologies to enable automated imaging and scoring of tissue-specific phenotypes at enhanced resolution. Here, we present the development of an automated imaging pipeline to identify chemical modifiers of glomerular cyst formation in a zebrafish model for human cystic kidney disease. Morpholino-mediated knockdown of intraflagellar transport protein Ift172 in Tg(wt1b:EGFP) embryos was used to induce large glomerular cysts representing a robustly scorable phenotypic readout. Compound-treated embryos were consistently aligned within the cavities of agarose-filled microplates. By interfacing feature detection algorithms with automated microscopy, a smart imaging workflow for detection, centring and zooming in on regions of interests was established, which enabled the automated capturing of standardised higher resolution datasets of pronephric areas. High-content screening datasets were processed and analysed using custom-developed heuristic algorithms implemented in common open-source image analysis software. The workflow enables highly efficient profiling of entire compound libraries and scoring of kidney-specific morphological phenotypes in thousands of zebrafish embryos. The demonstrated toolset covers all the aspects of a complex whole organism screening assay and can be adapted to other organs, specimens or applications.
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Affiliation(s)
- Gunjan Pandey
- Acquifer is a division of Ditabis, Digital Biomedical Imaging Systems AG, 75179 Pforzheim, Germany.
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120 Heidelberg, Germany.
| | - Jens H Westhoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120 Heidelberg, Germany.
| | - Franz Schaefer
- Department of Pediatrics I, University Children's Hospital Heidelberg, 69120 Heidelberg, Germany.
| | - Jochen Gehrig
- Acquifer is a division of Ditabis, Digital Biomedical Imaging Systems AG, 75179 Pforzheim, Germany.
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C2orf71a/pcare1 is important for photoreceptor outer segment morphogenesis and visual function in zebrafish. Sci Rep 2018; 8:9675. [PMID: 29946172 PMCID: PMC6018674 DOI: 10.1038/s41598-018-27928-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/17/2018] [Indexed: 02/03/2023] Open
Abstract
Mutations in C2orf71 are causative for autosomal recessive retinitis pigmentosa and occasionally cone-rod dystrophy. We have recently discovered that the protein encoded by this gene is important for modulation of the ciliary membrane through the recruitment of an actin assembly module, and have therefore renamed the gene to PCARE (photoreceptor cilium actin regulator). Here, we report on the identification of two copies of the c2orf71/pcare gene in zebrafish, pcare1 and pcare2. To study the role of the gene most similar to human PCARE, pcare1, we have generated a stable pcare1 mutant zebrafish model (designated pcare1rmc100/rmc100) in which the coding sequence was disrupted using CRISPR/Cas9 technology. Retinas of both embryonic (5 dpf) and adult (6 mpf) pcare1rmc100/rmc100 zebrafish display a clear disorganization of photoreceptor outer segments, resembling the phenotype observed in Pcare−/− mice. Optokinetic response and visual motor response measurements indicated visual impairment in pcare1rmc100/rmc100 zebrafish larvae at 5 dpf. In addition, electroretinogram measurements showed decreased b-wave amplitudes in pcare1rmc100/rmc100 zebrafish as compared to age- and strain-matched wild-type larvae, indicating a defect in the transretinal current. Altogether, our data show that lack of pcare1 causes a retinal phenotype in zebrafish and indicate that the function of the PCARE gene is conserved across species.
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Gupta PR, Pendse N, Greenwald SH, Leon M, Liu Q, Pierce EA, Bujakowska KM. Ift172 conditional knock-out mice exhibit rapid retinal degeneration and protein trafficking defects. Hum Mol Genet 2018; 27:2012-2024. [PMID: 29659833 PMCID: PMC5961092 DOI: 10.1093/hmg/ddy109] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/19/2018] [Accepted: 03/26/2018] [Indexed: 01/01/2023] Open
Abstract
Intraflagellar transport (IFT) is a bidirectional transport process that occurs along primary cilia and specialized sensory cilia, such as photoreceptor outersegments. Genes coding for various IFT components are associated with ciliopathies. Mutations in IFT172 lead to diseases ranging from isolated retinal degeneration to severe syndromic ciliopathies. In this study, we created a mouse model of IFT172-associated retinal degeneration to investigate the ocular disease mechanism. We found that depletion of IFT172 in rod photoreceptors leads to a rapid degeneration of the retina, with severely reduced electroretinography (ERG) responses by 1 month and complete outer-nuclear layer (ONL) degeneration by 2 months. We investigated molecular mechanisms of degeneration and show that IFT172 protein reduction leads to mislocalization of specific photoreceptor outersegment (OS) proteins (RHO, RP1, IFT139), aberrant light-driven translocation of alpha transducin and altered localization of glioma-associated oncogene family member 1 (GLI1). This mouse model exhibits key features of the retinal phenotype observed in patients with IFT172-associated blindness and can be used for in vivo testing of ciliopathy therapies.
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Affiliation(s)
- Priya R Gupta
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
- Weill Cornell Medical College, New York, NY 10021, USA
| | - Nachiket Pendse
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Scott H Greenwald
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Mihoko Leon
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Qin Liu
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Eric A Pierce
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Kinga M Bujakowska
- Department of Ophthalmology, Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
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25
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Crespo C, Soroldoni D, Knust E. A novel transgenic zebrafish line for red opsin expression in outer segments of photoreceptor cells. Dev Dyn 2018; 247:951-959. [PMID: 29603474 PMCID: PMC6099204 DOI: 10.1002/dvdy.24631] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Opsins are a group of light-sensitive proteins present in photoreceptor cells, which convert the energy of photons into electrochemical signals, thus allowing vision. Given their relevance, we aimed to visualize the two red opsins at subcellular scale in photoreceptor cells. RESULTS We generated a novel Zebrafish BAC transgenic line, which express fluorescently tagged, full-length Opsin 1 long-wave-sensitive 1 (Opn1lw1) and full-length Opsin 1 long-wave-sensitive 2 (Opn1lw2) under the control of their endogenous promoters. Both fusion proteins are localized in the outer segments of photoreceptor cells. During development, Opn1lw2-mKate2 is detected from the initial formation of outer segments onward. In contrast, Opn1lw1-mNeonGreen is first detected in juvenile Zebrafish at about 2 weeks postfertilization, and both opsins continue to be expressed throughout adulthood. It is important to note that the presence of the transgene did not significantly alter the size of outer segments. CONCLUSIONS We have generated a transgenic line that mimics the endogenous expression pattern of Opn1lw1 and Opn1lw2 in the developing and adult retina. In contrast to existing lines, our transgene design allows to follow protein localization. Hence, we expect that these lines could act as useful real-time reporters to directly measure phenomena in retinal development and disease models. Developmental Dynamics 247:951-959, 2018. © 2018 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Cátia Crespo
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | - Elisabeth Knust
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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26
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Ojeda Naharros I, Cristian FB, Zang J, Gesemann M, Ingham PW, Neuhauss SCF, Bachmann-Gagescu R. The ciliopathy protein TALPID3/KIAA0586 acts upstream of Rab8 activation in zebrafish photoreceptor outer segment formation and maintenance. Sci Rep 2018; 8:2211. [PMID: 29396404 PMCID: PMC5797153 DOI: 10.1038/s41598-018-20489-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/19/2018] [Indexed: 12/12/2022] Open
Abstract
Ciliopathies are human disorders caused by dysfunction of primary cilia, ubiquitous microtubule-based organelles involved in signal transduction. Cilia are anchored inside the cell through basal bodies (BBs), modified centrioles also acting as microtubule-organization centers. Photoreceptors (PRs) are sensory neurons, whose primary cilium forms a highly specialized compartment called the outer segment (OS) responsible for sensing incoming light. Thus, ciliopathies often present with retinal degeneration. Mutations in KIAA0586/TALPID3 (TA3) cause Joubert syndrome, in which 30% of affected individuals develop retinal involvement. To elucidate the function of TALPID3 in PRs, we studied talpid3 zebrafish mutants and identified a progressive retinal degeneration phenotype. The majority of PRs lack OS development due to defects in BB positioning and docking at the apical cell surface. Intracellular accumulation of the photopigment opsin leads to PR cell death of moderate severity. Electroretinograms demonstrate severe visual impairement. A small subset of PRs display normally docked BBs and extended OSs through rescue by maternally-deposited Talpid3. While localization of the small GTPase Rab8a, which plays an important role in BB docking, appears unaffected in talpid3-/- PRs, overexpression of constitutively active Rab8a rescues OS formation, indicating that the role of Ta3 in early ciliogenesis lies upstream of Rab8a activation in PRs.
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Affiliation(s)
- Irene Ojeda Naharros
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland
| | - Flavia B Cristian
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland
- Department of Human Molecular Genetics, Institute of Human Genetics, University of Heidelberg, Heidelberg, Germany
| | - Jingjing Zang
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland
| | - Matthias Gesemann
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland
| | - Philip W Ingham
- Lee Kong Chian School of Medicine, Nanyang Technological University, 639798, Singapore, Singapore
| | - Stephan C F Neuhauss
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland
| | - Ruxandra Bachmann-Gagescu
- Institute for Molecular Life Sciences, University of Zurich, 8057, Zurich, Switzerland.
- Institute for Medical Genetics, University of Zurich, 8952, Schlieren, Switzerland.
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27
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Ojeda Naharros I, Gesemann M, Mateos JM, Barmettler G, Forbes A, Ziegler U, Neuhauss SCF, Bachmann-Gagescu R. Loss-of-function of the ciliopathy protein Cc2d2a disorganizes the vesicle fusion machinery at the periciliary membrane and indirectly affects Rab8-trafficking in zebrafish photoreceptors. PLoS Genet 2017; 13:e1007150. [PMID: 29281629 PMCID: PMC5760100 DOI: 10.1371/journal.pgen.1007150] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 01/09/2018] [Accepted: 12/11/2017] [Indexed: 12/22/2022] Open
Abstract
Ciliopathies are human disorders caused by dysfunction of primary cilia, ubiquitous organelles involved in transduction of environmental signals such as light sensation in photoreceptors. Concentration of signal detection proteins such as opsins in the ciliary membrane is achieved by RabGTPase-regulated polarized vesicle trafficking and by a selective barrier at the ciliary base, the transition zone (TZ). Dysfunction of the TZ protein CC2D2A causes Joubert/Meckel syndromes in humans and loss of ciliary protein localization in animal models, including opsins in retinal photoreceptors. The link between the TZ and upstream vesicle trafficking has been little explored to date. Moreover, the role of the small GTPase Rab8 in opsin-carrier vesicle (OCV) trafficking has been recently questioned in a mouse model. Using correlative light and electron microscopy and live imaging in zebrafish photoreceptors, we provide the first live characterization of Rab8-mediated trafficking in photoreceptors in vivo. Our results support a possibly redundant role for both Rab8a/b paralogs in OCV trafficking, based on co-localization of Rab8 and opsins in vesicular structures, and joint movement of Rab8-tagged particles with opsin. We further investigate the role of the TZ protein Cc2d2a in Rab8-mediated trafficking using cc2d2a zebrafish mutants and identify a requirement for Cc2d2a in the latest step of OCV trafficking, namely vesicle fusion. Progressive accumulation of opsin-containing vesicles in the apical portion of photoreceptors lacking Cc2d2a is caused by disorganization of the vesicle fusion machinery at the periciliary membrane with mislocalization and loss of the t-SNAREs SNAP25 and Syntaxin3 and of the exocyst component Exoc4. We further observe secondary defects on upstream Rab8-trafficking with cytoplasmic accumulation of Rab8. Taken together, our results support participation of Rab8 in OCV trafficking and identify a novel role for the TZ protein Cc2d2a in fusion of incoming ciliary-directed vesicles, through organization of the vesicle fusion machinery at the periciliary membrane. Ciliopathies are human disorders caused by dysfunction of primary cilia, ubiquitous organelles involved in transduction of environmental signals to the cells. Concentration and regulation of signal detection proteins in the ciliary membrane is therefore tightly regulated through polarized vesicle trafficking and through a selective barrier at the ciliary base called the transition zone (TZ). Dysfunction of TZ proteins leads to human ciliopathies and to aberrant localization of ciliary proteins in animal models. In this work, we use zebrafish retinal photoreceptors as a model to explore the relationship between the TZ and upstream vesicle trafficking. Relying on modern technologies such as correlative light and electron microscopy and live imaging of fluorescently-tagged proteins, we identify a role for the TZ protein CC2D2A in organizing the components required for vesicle fusion at the periciliary membrane. We also characterize the movement dynamics of vesicles carrying light-detection proteins (opsins) towards the ciliary compartment of photoreceptors in vivo and provide novel data in support of the recently questioned involvement of the small GTPase Rab8 in opsin-carrier vesicle trafficking in photoreceptors.
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Affiliation(s)
| | - Matthias Gesemann
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - José M. Mateos
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Gery Barmettler
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Austin Forbes
- Fred Hutchison Cancer Research Center, Seattle, Washington, United States of America
| | - Urs Ziegler
- Center for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | | | - Ruxandra Bachmann-Gagescu
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
- * E-mail:
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28
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Seo S, Datta P. Photoreceptor outer segment as a sink for membrane proteins: hypothesis and implications in retinal ciliopathies. Hum Mol Genet 2017; 26:R75-R82. [PMID: 28453661 DOI: 10.1093/hmg/ddx163] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 04/24/2017] [Indexed: 12/28/2022] Open
Abstract
The photoreceptor outer segment (OS) is a unique modification of the primary cilium, specialized for light perception. Being homologous organelles, the primary cilium and the OS share common building blocks and molecular machinery to construct and maintain them. The OS, however, has several unique structural features that are not seen in primary cilia. Although these unique features of the OS have been well documented, their implications in protein localization have been under-appreciated. In this review, we compare the structural properties of the primary cilium and the OS, and propose a hypothesis that the OS can act as a sink for membrane proteins. We further discuss the implications of this hypothesis in polarized protein localization in photoreceptors and mechanisms of photoreceptor degeneration in retinal ciliopathies.
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Affiliation(s)
- Seongjin Seo
- Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Poppy Datta
- Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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29
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Lobo GP, Fulmer D, Guo L, Zuo X, Dang Y, Kim SH, Su Y, George K, Obert E, Fogelgren B, Nihalani D, Norris RA, Rohrer B, Lipschutz JH. The exocyst is required for photoreceptor ciliogenesis and retinal development. J Biol Chem 2017; 292:14814-14826. [PMID: 28729419 DOI: 10.1074/jbc.m117.795674] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/10/2017] [Indexed: 11/06/2022] Open
Abstract
We previously have shown that the highly conserved eight-protein exocyst trafficking complex is required for ciliogenesis in kidney tubule cells. We hypothesized here that ciliogenic programs are conserved across organs and species. To determine whether renal primary ciliogenic programs are conserved in the eye, and to characterize the function and mechanisms by which the exocyst regulates eye development in zebrafish, we focused on exoc5, a central component of the exocyst complex, by analyzing both exoc5 zebrafish mutants, and photoreceptor-specific Exoc5 knock-out mice. Two separate exoc5 mutant zebrafish lines phenocopied exoc5 morphants and, strikingly, exhibited a virtual absence of photoreceptors, along with abnormal retinal development and cell death. Because the zebrafish mutant was a global knockout, we also observed defects in several ciliated organs, including the brain (hydrocephalus), heart (cardiac edema), and kidney (disordered and shorter cilia). exoc5 knockout increased phosphorylation of the regulatory protein Mob1, consistent with Hippo pathway activation. exoc5 mutant zebrafish rescue with human EXOC5 mRNA completely reversed the mutant phenotype. We accomplished photoreceptor-specific knockout of Exoc5 with our Exoc5 fl/fl mouse line crossed with a rhodopsin-Cre driver line. In Exoc5 photoreceptor-specific knock-out mice, the photoreceptor outer segment structure was severely impaired at 4 weeks of age, although a full-field electroretinogram indicated a visual response was still present. However, by 6 weeks, visual responses were eliminated. In summary, we show that ciliogenesis programs are conserved in the kidneys and eyes of zebrafish and mice and that the exocyst is necessary for photoreceptor ciliogenesis and retinal development, most likely by trafficking cilia and outer-segment proteins.
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Affiliation(s)
- Glenn P Lobo
- From the Departments of Medicine.,Ophthalmology, and
| | - Diana Fulmer
- From the Departments of Medicine.,Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Lilong Guo
- From the Departments of Medicine.,Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | | | | | | | | | | | | | - Ben Fogelgren
- the Department of Anatomy, Biochemistry, and Physiology, University of Hawaii at Manoa, Honolulu, Hawaii 96813
| | | | - Russell A Norris
- Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Bärbel Rohrer
- Ophthalmology, and.,the Division of Research, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina 29401, and
| | - Joshua H Lipschutz
- From the Departments of Medicine, .,the Department of Medicine, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina 29425
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30
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Goulding SP, Szumlinski KK, Contet C, MacCoss MJ, Wu CC. A mass spectrometry-based proteomic analysis of Homer2-interacting proteins in the mouse brain. J Proteomics 2017; 166:127-137. [PMID: 28728878 DOI: 10.1016/j.jprot.2017.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 07/08/2017] [Accepted: 07/12/2017] [Indexed: 11/26/2022]
Abstract
In the brain, the Homer protein family modulates excitatory signal transduction and receptor plasticity through interactions with other proteins in dendritic spines. Homer proteins are implicated in a variety of psychiatric disorders such as schizophrenia and addiction. Since long Homers serve as scaffolding proteins, identifying their interacting partners is an important first step in understanding their biological function and could help to guide the design of new therapeutic strategies. The present study set out to document Homer2-interacting proteins in the mouse brain using a co-immunoprecipitation-based mass spectrometry approach where Homer2 knockout samples were used to filter out non-specific interactors. We found that in the mouse brain, Homer2 interacts with a limited subset of its previously reported interacting partners (3 out of 31). Importantly, we detected an additional 15 novel Homer2-interacting proteins, most of which are part of the N-methyl-D-aspartate receptor signaling pathway. These results corroborate the central role Homer2 plays in glutamatergic transmission and expand the network of proteins potentially contributing to the behavioral abnormalities associated with altered Homer2 expression. SIGNIFICANCE Long Homer proteins are scaffolding proteins that regulate signal transduction in neurons. Identifying their interacting partners is key to understanding their function. We used co-immunoprecipitation in combination with mass spectrometry to establish the first comprehensive list of Homer2-interacting partners in the mouse brain. The specificity of interactions was evaluated using Homer2 knockout brain tissue as a negative control. The set of proteins that we identified minimally overlaps with previously reported interacting partners of Homer2; however, we identified novel interactors that are part of a signaling cascade activated by glutamatergic transmission, which improves our mechanistic understanding of the role of Homer2 in behavior.
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Affiliation(s)
- Scott P Goulding
- Department of Neuroscience, The Scripps Research Institute, La Jolla, CA, United States; Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States; Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States.
| | - Karen K Szumlinski
- Department of Psychological and Brain Sciences, Molecular, Cellular and Developmental Biology, The Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Candice Contet
- Department of Neuroscience, The Scripps Research Institute, La Jolla, CA, United States
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, United States
| | - Christine C Wu
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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31
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Van De Weghe JC, Rusterholz TD, Latour B, Grout ME, Aldinger KA, Shaheen R, Dempsey JC, Maddirevula S, Cheng YHH, Phelps IG, Gesemann M, Goel H, Birk OS, Alanzi T, Rawashdeh R, Khan AO, Bamshad MJ, Nickerson DA, Neuhauss SC, Dobyns WB, Alkuraya FS, Roepman R, Bachmann-Gagescu R, Doherty D, Doherty D. Mutations in ARMC9, which Encodes a Basal Body Protein, Cause Joubert Syndrome in Humans and Ciliopathy Phenotypes in Zebrafish. Am J Hum Genet 2017. [PMID: 28625504 DOI: 10.1016/j.ajhg.2017.05.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Joubert syndrome (JS) is a recessive neurodevelopmental disorder characterized by hypotonia, ataxia, abnormal eye movements, and variable cognitive impairment. It is defined by a distinctive brain malformation known as the "molar tooth sign" on axial MRI. Subsets of affected individuals have malformations such as coloboma, polydactyly, and encephalocele, as well as progressive retinal dystrophy, fibrocystic kidney disease, and liver fibrosis. More than 35 genes have been associated with JS, but in a subset of families the genetic cause remains unknown. All of the gene products localize in and around the primary cilium, making JS a canonical ciliopathy. Ciliopathies are unified by their overlapping clinical features and underlying mechanisms involving ciliary dysfunction. In this work, we identify biallelic rare, predicted-deleterious ARMC9 variants (stop-gain, missense, splice-site, and single-exon deletion) in 11 individuals with JS from 8 families, accounting for approximately 1% of the disorder. The associated phenotypes range from isolated neurological involvement to JS with retinal dystrophy, additional brain abnormalities (e.g., heterotopia, Dandy-Walker malformation), pituitary insufficiency, and/or synpolydactyly. We show that ARMC9 localizes to the basal body of the cilium and is upregulated during ciliogenesis. Typical ciliopathy phenotypes (curved body shape, retinal dystrophy, coloboma, and decreased cilia) in a CRISPR/Cas9-engineered zebrafish mutant model provide additional support for ARMC9 as a ciliopathy-associated gene. Identifying ARMC9 mutations as a cause of JS takes us one step closer to a full genetic understanding of this important disorder and enables future functional work to define the central biological mechanisms underlying JS and other ciliopathies.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Dan Doherty
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA.
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32
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Daniele LL, Emran F, Lobo GP, Gaivin RJ, Perkins BD. Mutation of wrb, a Component of the Guided Entry of Tail-Anchored Protein Pathway, Disrupts Photoreceptor Synapse Structure and Function. Invest Ophthalmol Vis Sci 2017; 57:2942-54. [PMID: 27273592 PMCID: PMC4898200 DOI: 10.1167/iovs.15-18996] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PURPOSE Tail-anchored (TA) proteins contain a single hydrophobic domain at the C-terminus and are posttranslationally inserted into the ER membrane via the GET (guided entry of tail-anchored proteins) pathway. The role of the GET pathway in photoreceptors is unexplored. The goal of this study was to characterize the zebrafish pinball wizard mutant, which disrupts Wrb, a core component of the GET pathway. METHODS Electroretinography, optokinetic response measurements (OKR), immunohistochemistry, and electron microscopy analyses were employed to assess ribbon synapse function, protein expression, and ultrastructure in 5-day-old zebrafish larvae. Expression of wrb was investigated with real-time qRT-PCR and in situ hybridization. RESULTS Mutation of wrb abolished the OKR and greatly diminished the ERG b-wave, but not the a-wave. Ribeye and SV2 were partially mislocalized in both photoreceptors and hair cells of wrb mutants. Fewer contacts were seen between photoreceptors and bipolar cells in wrb-/- mutants. Expression of wrb was observed throughout the nervous system and Wrb localized to the ER and synaptic region of photoreceptors. Morpholino knockdown of the cytosolic ATPase trc40, which targets TA proteins to the ER, also diminished the OKR. Overexpression of wrb fully restored contrast sensitivity in mutants, while overexpression of mutant wrbR73A, which cannot bind Trc40, did not. CONCLUSIONS Proteins Wrb and Trc40 are required for synaptic transmission between photoreceptors and bipolar cells, indicating that TA protein insertion by the TRC pathway is a critical step in ribbon synapse assembly and function.
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Affiliation(s)
- Lauren L Daniele
- Department of Ophthalmic Research Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Farida Emran
- Centre for Research in Neuroscience, McGill University, Montreal, Quebec, Canada
| | - Glenn P Lobo
- Department of Ophthalmic Research Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Robert J Gaivin
- Department of Ophthalmic Research Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Brian D Perkins
- Department of Ophthalmic Research Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
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Song P, Dudinsky L, Fogerty J, Gaivin R, Perkins BD. Arl13b Interacts With Vangl2 to Regulate Cilia and Photoreceptor Outer Segment Length in Zebrafish. Invest Ophthalmol Vis Sci 2017; 57:4517-26. [PMID: 27571019 PMCID: PMC5015978 DOI: 10.1167/iovs.16-19898] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Mutations in the gene ARL13B cause the classical form of Joubert syndrome, an autosomal recessive ciliopathy with variable degrees of retinal degeneration. As second-site modifier alleles can contribute to retinal pathology in ciliopathies, animal models provide a unique platform to test how genetic interactions modulate specific phenotypes. In this study, we analyzed the zebrafish arl13b mutant for retinal degeneration and for epistatic relationships with the planar cell polarity protein (PCP) component vangl2. METHODS Photoreceptor and cilia structure was examined by light and electron microscopy. Immunohistochemistry was performed to examine ciliary markers. Genetic interactions were tested by pairwise crosses of heterozygous animals. Genetic mosaic animals were generated by blastula transplantation and analyzed by fluorescence microscopy. RESULTS At 5 days after fertilization, photoreceptor outer segments were shorter in zebrafish arl13b-/- mutants compared to wild-type larvae, no overt signs of retinal degeneration were observed by light or electron microscopy. Starting at 14 days after fertilization (dpf) and continuing through 30 dpf, cells lacking Arl13b died following transplantation into wild-type host animals. Photoreceptors of arl13b-/-;vangl2-/- mutants were more compromised than the photoreceptors of single mutants. Finally, when grown within a wild-type retina, the vangl2-/- mutant cone photoreceptors displayed normal basal body positioning. CONCLUSIONS We show that arl13b-/- mutants have shortened cilia and photoreceptor outer segments and exhibit a slow, progressive photoreceptor degeneration that occurs over weeks. The data suggest that loss of Arl13b leads to slow photoreceptor degeneration, but can be exacerbated by the loss of vangl2. Importantly, the data show that Arl13b can genetically and physically interact with Vangl2 and this association is important for normal photoreceptor structure. The loss of vangl2, however, does not affect basal body positioning.
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Affiliation(s)
- Ping Song
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Lynn Dudinsky
- Department of Biology, Texas A&M University, College Station, Texas, United States
| | - Joseph Fogerty
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Robert Gaivin
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Brian D Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States 2Department of Biology, Texas A&M University, College Station, Texas, United States
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May-Simera H, Nagel-Wolfrum K, Wolfrum U. Cilia - The sensory antennae in the eye. Prog Retin Eye Res 2017; 60:144-180. [PMID: 28504201 DOI: 10.1016/j.preteyeres.2017.05.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 12/21/2022]
Abstract
Cilia are hair-like projections found on almost all cells in the human body. Originally believed to function merely in motility, the function of solitary non-motile (primary) cilia was long overlooked. Recent research has demonstrated that primary cilia function as signalling hubs that sense environmental cues and are pivotal for organ development and function, tissue hoemoestasis, and maintenance of human health. Cilia share a common anatomy and their diverse functional features are achieved by evolutionarily conserved functional modules, organized into sub-compartments. Defects in these functional modules are responsible for a rapidly growing list of human diseases collectively termed ciliopathies. Ocular pathogenesis is common in virtually all classes of syndromic ciliopathies, and disruptions in cilia genes have been found to be causative in a growing number of non-syndromic retinal dystrophies. This review will address what is currently known about cilia contribution to visual function. We will focus on the molecular and cellular functions of ciliary proteins and their role in the photoreceptor sensory cilia and their visual phenotypes. We also highlight other ciliated cell types in tissues of the eye (e.g. lens, RPE and Müller glia cells) discussing their possible contribution to disease progression. Progress in basic research on the cilia function in the eye is paving the way for therapeutic options for retinal ciliopathies. In the final section we describe the latest advancements in gene therapy, read-through of non-sense mutations and stem cell therapy, all being adopted to treat cilia dysfunction in the retina.
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Affiliation(s)
- Helen May-Simera
- Institute of Molecular Physiology, Cilia Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - Kerstin Nagel-Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - Uwe Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany.
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Blanco-Sánchez B, Clément A, Phillips JB, Westerfield M. Zebrafish models of human eye and inner ear diseases. Methods Cell Biol 2016; 138:415-467. [PMID: 28129854 DOI: 10.1016/bs.mcb.2016.10.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Eye and inner ear diseases are the most common sensory impairments that greatly impact quality of life. Zebrafish have been intensively employed to understand the fundamental mechanisms underlying eye and inner ear development. The zebrafish visual and vestibulo-acoustic systems are very similar to these in humans, and although not yet mature, they are functional by 5days post-fertilization (dpf). In this chapter, we show how the zebrafish has significantly contributed to the field of biomedical research and how researchers, by establishing disease models and meticulously characterizing their phenotypes, have taken the first steps toward therapies. We review here models for (1) eye diseases, (2) ear diseases, and (3) syndromes affecting eye and/or ear. The use of new genome editing technologies and high-throughput screening systems should increase considerably the speed at which knowledge from zebrafish disease models is acquired, opening avenues for better diagnostics, treatments, and therapies.
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Affiliation(s)
| | - A Clément
- University of Oregon, Eugene, OR, United States
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36
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Raghupathy RK, Zhang X, Alhasani RH, Zhou X, Mullin M, Reilly J, Li W, Liu M, Shu X. Abnormal photoreceptor outer segment development and early retinal degeneration in kif3a mutant zebrafish. Cell Biochem Funct 2016; 34:429-40. [PMID: 27470972 DOI: 10.1002/cbf.3205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/29/2016] [Accepted: 06/30/2016] [Indexed: 01/09/2023]
Abstract
Photoreceptors are highly specialized sensory neurons that possess a modified primary cilium called the outer segment. Photoreceptor outer segment formation and maintenance require highly active protein transport via a process known as intraflagellar transport. Anterograde transport in outer segments is powered by the heterotrimeric kinesin II and coordinated by intraflagellar transport proteins. Here, we describe a new zebrafish model carrying a nonsense mutation in the kinesin II family member 3A (kif3a) gene. Kif3a mutant zebrafish exhibited curved body axes and kidney cysts. Outer segments were not formed in most parts of the mutant retina, and rhodopsin was mislocalized, suggesting KIF3A has a role in rhodopsin trafficking. Both rod and cone photoreceptors degenerated rapidly between 4 and 9 days post fertilization, and electroretinography response was not detected in 7 days post fertilization mutant larvae. Loss of KIF3A in zebrafish also resulted in an intracellular transport defect affecting anterograde but not retrograde transport of organelles. Our results indicate KIF3A plays a conserved role in photoreceptor outer segment formation and intracellular transport.
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Affiliation(s)
| | - Xun Zhang
- Department of Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Reem H Alhasani
- Department of Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Xinzhi Zhou
- Department of Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | | | - James Reilly
- Department of Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Wenchang Li
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xinhua Shu
- Department of Life Sciences, Glasgow Caledonian University, Glasgow, UK
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Lepanto P, Davison C, Casanova G, Badano JL, Zolessi FR. Characterization of primary cilia during the differentiation of retinal ganglion cells in the zebrafish. Neural Dev 2016; 11:10. [PMID: 27053191 PMCID: PMC4823885 DOI: 10.1186/s13064-016-0064-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/29/2016] [Indexed: 01/05/2023] Open
Abstract
Background Retinal ganglion cell (RGC) differentiation in vivo is a highly stereotyped process, likely resulting from the interaction of cell type-specific transcription factors and tissue-derived signaling factors. The primary cilium, as a signaling hub in the cell, may have a role during this process but its presence and localization during RGC generation, and its contribution to the process of cell differentiation, have not been previously assessed in vivo. Methods In this work we analyzed the distribution of primary cilia in vivo using laser scanning confocal microscopy, as well as their main ultrastructural features by transmission electron microscopy, in the early stages of retinal histogenesis in the zebrafish, around the time of RGC generation and initial differentiation. In addition, we knocked-down ift88 and elipsa, two genes with an essential role in cilia generation and maintenance, a treatment that caused a general reduction in organelle size. The effect on retinal development and RGC differentiation was assessed by confocal microscopy of transgenic or immunolabeled embryos. Results Our results show that retinal neuroepithelial cells have an apically-localized primary cilium usually protruding from the apical membrane. We also found a small proportion of sub-apical cilia, before and during the neurogenic period. This organelle was also present in an apical position in neuroblasts during apical process retraction and dendritogenesis, although between these stages cilia appeared highly dynamic regarding both presence and position. Disruption of cilia caused a decrease in the proliferation of retinal progenitors and a reduction of neural retina volume. In addition, retinal histogenesis was globally delayed albeit RGC layer formation was preferentially reduced with respect to the amacrine and photoreceptor cell layers. Conclusions These results indicate that primary cilia exhibit a highly dynamic behavior during early retinal differentiation, and that they are required for the proliferation and survival of retinal progenitors, as well as for neuronal generation, particularly of RGCs. Electronic supplementary material The online version of this article (doi:10.1186/s13064-016-0064-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paola Lepanto
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay
| | - Camila Davison
- Cell Biology of Neural Development Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay.,Sección Biología Celular, Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay
| | - Gabriela Casanova
- Unidad de Microscopía Electrónica, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay
| | - Jose L Badano
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay.
| | - Flavio R Zolessi
- Cell Biology of Neural Development Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay. .,Sección Biología Celular, Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay.
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Song Z, Zhang X, Jia S, Yelick PC, Zhao C. Zebrafish as a Model for Human Ciliopathies. J Genet Genomics 2016; 43:107-20. [DOI: 10.1016/j.jgg.2016.02.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/22/2022]
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Mutations in the Dynein1 Complex are Permissible for Basal Body Migration in Photoreceptors but Alter Rab6 Localization. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:209-15. [PMID: 26427413 DOI: 10.1007/978-3-319-17121-0_28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The photoreceptor outer segment is a specialized primary cilium, and anchoring of the basal body at the apical membrane is required for outer segment formation. We hypothesized that basal body localization and outer segment formation would require the microtubule motor dynein 1 and analyzed the zebrafish cannonball and mike oko mutants, which carry mutations in the heavy chain subunit of cytoplasmic dynein 1 (dync1h1) and the p150(Glued) subunit of Dynactin (dctn1a). The distribution of Rab6, a player in the post-Golgi trafficking of rhodopsin, was also examined. Basal body docking was unaffected in both mutants, but Rab6 expression was reduced. The results suggest that dynein 1 is dispensable for basal body docking but that outer segment defects may be due to defects in post-Golgi trafficking.
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40
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Abstract
Visual defects affect a large proportion of humanity, have a significant negative impact on quality of life, and cause significant economic burden. The wide variety of visual disorders and the large number of gene mutations responsible require a flexible animal model system to carry out research for possible causes and cures for the blinding conditions. With eyes similar to humans in structure and function, zebrafish are an important vertebrate model organism that is being used to study genetic and environmental eye diseases, including myopia, glaucoma, retinitis pigmentosa, ciliopathies, albinism, and diabetes. This review details the use of zebrafish in modeling human ocular diseases.
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Affiliation(s)
- Brian A Link
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226; ,
| | - Ross F Collery
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226; ,
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41
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Choi SY, Baek JI, Zuo X, Kim SH, Dunaief JL, Lipschutz JH. Cdc42 and sec10 Are Required for Normal Retinal Development in Zebrafish. Invest Ophthalmol Vis Sci 2015; 56:3361-70. [PMID: 26024121 DOI: 10.1167/iovs.14-15692] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To characterize the function and mechanisms of cdc42 and sec10 in eye development in zebrafish. METHODS Knockdown of zebrafish cdc42 and sec10 was carried out using antisense morpholino injection. The phenotype of morphants was characterized by histology, immunohistology, and transmission electron microscopy (TEM). To investigate a synergistic genetic interaction between cdc42 and sec10, we titrated suboptimal doses of cdc42 and sec10 morpholinos, and coinjected both morpholinos. To study trafficking, a melanosome transport assay was performed using epinephrine. RESULTS Cdc42 and sec10 knockdown in zebrafish resulted in both abnormal eye development and increased retinal cell death. Cdc42 morphants had a relatively normal retinal structure, aside from the absence of most connecting cilia and outer segments, whereas in sec10 morphants, much of the outer nuclear layer, which is composed of the photoreceptor nuclei, was missing and RPE cell thickness was markedly irregular. Knockdown of cdc42 and sec10 also resulted in an intracellular transport defect affecting retrograde melanosome transport. Furthermore, there was a synergistic genetic interaction between zebrafish cdc42 and sec10, suggesting that cdc42 and sec10 act in the same pathway in retinal development. CONCLUSIONS We propose a model whereby sec10 and cdc42 play a central role in development of the outer segment of the retinal photoreceptor cell by trafficking proteins necessary for ciliogenesis.
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Affiliation(s)
- Soo Young Choi
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Jeong-In Baek
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Xiaofeng Zuo
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Seok-Hyung Kim
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Joshua L Dunaief
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Joshua H Lipschutz
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States 3Department of Medicine, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina, United States
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42
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Jiang L, Wei Y, Ronquillo CC, Marc RE, Yoder BK, Frederick JM, Baehr W. Heterotrimeric kinesin-2 (KIF3) mediates transition zone and axoneme formation of mouse photoreceptors. J Biol Chem 2015; 290:12765-78. [PMID: 25825494 DOI: 10.1074/jbc.m115.638437] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Indexed: 11/06/2022] Open
Abstract
Anterograde intraflagellar transport (IFT) employing kinesin-2 molecular motors has been implicated in trafficking of photoreceptor outer segment proteins. We generated embryonic retina-specific (prefix "emb") and adult tamoxifen-induced (prefix "tam") deletions of KIF3a and IFT88 in adult mice to study photoreceptor ciliogenesis and protein trafficking. In (emb)Kif3a(-/-) and in (emb)Ift88(-/-) mice, basal bodies failed to extend transition zones (connecting cilia) with outer segments, and visual pigments mistrafficked. In contrast, (tam)Kif3a(-/-) and (tam)Ift88(-/-) photoreceptor axonemes disintegrated slowly post-induction, starting distally, but rhodopsin and cone pigments trafficked normally for more than 2 weeks, a time interval during which the outer segment is completely renewed. The results demonstrate that visual pigments transport to the retinal outer segment despite removal of KIF3 and IFT88, and KIF3-mediated anterograde IFT is responsible for photoreceptor transition zone and axoneme formation.
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Affiliation(s)
- Li Jiang
- From the Departments of Ophthalmology and Visual Sciences and
| | - Yuxiao Wei
- From the Departments of Ophthalmology and Visual Sciences and
| | | | - Robert E Marc
- From the Departments of Ophthalmology and Visual Sciences and
| | - Bradley K Yoder
- the Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294, and
| | | | - Wolfgang Baehr
- From the Departments of Ophthalmology and Visual Sciences and the Department of Biology, University of Utah, Salt Lake City, Utah 84112 Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, Utah 84132,
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43
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IFT46 plays an essential role in cilia development. Dev Biol 2015; 400:248-57. [PMID: 25722189 DOI: 10.1016/j.ydbio.2015.02.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 02/10/2015] [Accepted: 02/13/2015] [Indexed: 11/20/2022]
Abstract
Cilia are microtubule-based structures that project into the extracellular space. Ciliary defects are associated with several human diseases, including polycystic kidney disease, primary ciliary dyskinesia, left-right axis patterning, hydrocephalus and retinal degeneration. However, the genetic and cellular biological control of ciliogenesis remains poorly understood. The IFT46 is one of the highly conserved intraflagellar transport complex B proteins. In zebrafish, ift46 is expressed in various ciliated tissues such as Kupffer׳s vesicle, pronephric ducts, ears and spinal cord. We show that ift46 is localized to the basal body. Knockdown of ift46 gene results in multiple phenotypes associated with various ciliopathies including kidney cysts, pericardial edema and ventral axis curvature. In ift46 morphants, cilia in kidney and spinal canal are shortened and abnormal. Similar ciliary defects are observed in otic vesicles, lateral line hair cells, olfactory pits, but not in Kupffer׳s vesicle. To explore the functions of Ift46 during mouse development, we have generated Ift46 knock-out mice. The Ift46 mutants have developmental defects in brain, neural tube and heart. In particular Ift46(-/-) homozygotes displays randomization of the embryo heart looping, which is a hallmark of defective left-right (L/R) axis patterning. Taken together, our results demonstrated that IFT46 has an essential role in vertebrate ciliary development.
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Eblimit A, Nguyen TMT, Chen Y, Esteve-Rudd J, Zhong H, Letteboer S, Van Reeuwijk J, Simons DL, Ding Q, Wu KM, Li Y, Van Beersum S, Moayedi Y, Xu H, Pickard P, Wang K, Gan L, Wu SM, Williams DS, Mardon G, Roepman R, Chen R. Spata7 is a retinal ciliopathy gene critical for correct RPGRIP1 localization and protein trafficking in the retina. Hum Mol Genet 2014; 24:1584-601. [PMID: 25398945 DOI: 10.1093/hmg/ddu573] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Leber congenital amaurosis (LCA) and juvenile retinitis pigmentosa (RP) are severe hereditary diseases that causes visual impairment in infants and children. SPATA7 has recently been identified as the LCA3 and juvenile RP gene in humans, whose function in the retina remains elusive. Here, we show that SPATA7 localizes at the primary cilium of cells and at the connecting cilium (CC) of photoreceptor cells, indicating that SPATA7 is a ciliary protein. In addition, SPATA7 directly interacts with the retinitis pigmentosa GTPase regulator interacting protein 1 (RPGRIP1), a key connecting cilium protein that has also been linked to LCA. In the retina of Spata7 null mutant mice, a substantial reduction of RPGRIP1 levels at the CC of photoreceptor cells is observed, suggesting that SPATA7 is required for the stable assembly and localization of the ciliary RPGRIP1 protein complex. Furthermore, our results pinpoint a role of this complex in protein trafficking across the CC to the outer segments, as we identified that rhodopsin accumulates in the inner segments and around the nucleus of photoreceptors. This accumulation then likely triggers the apoptosis of rod photoreceptors that was observed. Loss of Spata7 function in mice indeed results in a juvenile RP-like phenotype, characterized by progressive degeneration of photoreceptor cells and a strongly decreased light response. Together, these results indicate that SPATA7 functions as a key member of a retinal ciliopathy-associated protein complex, and that apoptosis of rod photoreceptor cells triggered by protein mislocalization is likely the mechanism of disease progression in LCA3/ juvenile RP patients.
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Affiliation(s)
| | - Thanh-Minh T Nguyen
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands
| | - Yiyun Chen
- HGSC, Department of Molecular and Human Genetics
| | - Julian Esteve-Rudd
- Jules Stein Eye Institute, UCLA David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Hua Zhong
- Department of Pathology and Immunology
| | - Stef Letteboer
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands
| | - Jeroen Van Reeuwijk
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands
| | - David L Simons
- Department of Neuroscience and Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Qian Ding
- Department of Ophthalmology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Ka Man Wu
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands
| | - Yumei Li
- HGSC, Department of Molecular and Human Genetics
| | - Sylvia Van Beersum
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands
| | | | - Huidan Xu
- HGSC, Department of Molecular and Human Genetics
| | | | - Keqing Wang
- HGSC, Department of Molecular and Human Genetics
| | - Lin Gan
- Department of Ophthalmology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Samuel M Wu
- Department of Neuroscience and Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - David S Williams
- Jules Stein Eye Institute, UCLA David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Graeme Mardon
- Department of Molecular and Human Genetics, Department of Pathology and Immunology, Department of Neuroscience and Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA,
| | - Ronald Roepman
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen 6525, The Netherlands,
| | - Rui Chen
- HGSC, Department of Molecular and Human Genetics,
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Bujakowska KM, Zhang Q, Siemiatkowska AM, Liu Q, Place E, Falk MJ, Consugar M, Lancelot ME, Antonio A, Lonjou C, Carpentier W, Mohand-Saïd S, den Hollander AI, Cremers FPM, Leroy BP, Gai X, Sahel JA, van den Born LI, Collin RWJ, Zeitz C, Audo I, Pierce EA. Mutations in IFT172 cause isolated retinal degeneration and Bardet-Biedl syndrome. Hum Mol Genet 2014; 24:230-42. [PMID: 25168386 DOI: 10.1093/hmg/ddu441] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Primary cilia are sensory organelles present on most mammalian cells. The assembly and maintenance of primary cilia are facilitated by intraflagellar transport (IFT), a bidirectional protein trafficking along the cilium. Mutations in genes coding for IFT components have been associated with a group of diseases called ciliopathies. These genetic disorders can affect a variety of organs including the retina. Using whole exome sequencing in three families, we identified mutations in Intraflagellar Transport 172 Homolog [IFT172 (Chlamydomonas)] that underlie an isolated retinal degeneration and Bardet-Biedl syndrome. Extensive functional analyses of the identified mutations in cell culture, rat retina and in zebrafish demonstrated their hypomorphic or null nature. It has recently been reported that mutations in IFT172 cause a severe ciliopathy syndrome involving skeletal, renal, hepatic and retinal abnormalities (Jeune and Mainzer-Saldino syndromes). Here, we report for the first time that mutations in this gene can also lead to an isolated form of retinal degeneration. The functional data for the mutations can partially explain milder phenotypes; however, the involvement of modifying alleles in the IFT172-associated phenotypes cannot be excluded. These findings expand the spectrum of disease associated with mutations in IFT172 and suggest that mutations in genes originally reported to be associated with syndromic ciliopathies should also be considered in subjects with non-syndromic retinal dystrophy.
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Affiliation(s)
- Kinga M Bujakowska
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France
| | - Qi Zhang
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | | | - Qin Liu
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Emily Place
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Marni J Falk
- Department of Pediatrics, Division of Human Genetics, The Children's Hospital of Philadelphia and University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Mark Consugar
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Marie-Elise Lancelot
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France
| | - Aline Antonio
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France
| | - Christine Lonjou
- Plateforme Post-génomique P3S, Hôpital Pitié Salpêtrière, Paris 75013, France
| | - Wassila Carpentier
- Plateforme Post-génomique P3S, Hôpital Pitié Salpêtrière, Paris 75013, France
| | - Saddek Mohand-Saïd
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France Institut National de la Santé et de la Recherche Médicale and Direction de L'Hospitalisation et de L'Organisation des Soins Centre D'Investigation Clinique 1423, Centre Hospitalier National D'Ophtalmologie des Quinze-Vingts, Paris 75012, France
| | - Anneke I den Hollander
- Department of Human Genetics Radboud Institute for Molecular Life Sciences, and Department of Ophthalmology, Radboud University Medical Center, Nijmegen 6500 HB, The Netherlands
| | - Frans P M Cremers
- Department of Human Genetics Radboud Institute for Molecular Life Sciences, and
| | - Bart P Leroy
- Department of Ophthalmology and Center for Medical Genetics, Ghent University Hospital and Ghent University, Ghent 9000, Belgium Ophthalmic Genetics and Visual Electrophysiology, Division of Ophthalmology, The Children's Hospital of Philadelphia, PA 19104, USA
| | - Xiaowu Gai
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - José-Alain Sahel
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France Institut National de la Santé et de la Recherche Médicale and Direction de L'Hospitalisation et de L'Organisation des Soins Centre D'Investigation Clinique 1423, Centre Hospitalier National D'Ophtalmologie des Quinze-Vingts, Paris 75012, France Fondation Ophtalmologique Adolphe de Rothschild, Paris 75019, France Academie des Sciences, Institut de France, Paris 75006, France University College London, Institute of Ophthalmology, London EC1V 9EL, UK and
| | | | - Rob W J Collin
- Department of Human Genetics Radboud Institute for Molecular Life Sciences, and
| | - Christina Zeitz
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France
| | - Isabelle Audo
- Institut National de la Santé et de la Recherche Médicale U968, Paris 75012, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, Paris 75012, France Centre National de la Recherche Scientifique, UMR_7210, Paris 75012, France Institut National de la Santé et de la Recherche Médicale and Direction de L'Hospitalisation et de L'Organisation des Soins Centre D'Investigation Clinique 1423, Centre Hospitalier National D'Ophtalmologie des Quinze-Vingts, Paris 75012, France University College London, Institute of Ophthalmology, London EC1V 9EL, UK and
| | - Eric A Pierce
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
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Lee C, Wallingford JB, Gross JM. Cluap1 is essential for ciliogenesis and photoreceptor maintenance in the vertebrate eye. Invest Ophthalmol Vis Sci 2014; 55:4585-92. [PMID: 24970261 DOI: 10.1167/iovs.14-14888] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To identify the mutation and cell biological underpinnings of photoreceptor defects in zebrafish au5 mutants. METHODS Whole genome sequencing and SNP mapping were used to determine the genomic interval that harbors the au5 mutation. A candidate mutation was cloned and sequenced, and mRNA rescue used to validate that the affected gene was correctly identified. In situ hybridization, immunohistochemistry, and confocal imaging were used to determine the effects on photoreceptor development and maintenance in mutant retinae, and to determine if ciliogenesis or cilia-dependent development was affected in mutant embryos. Expression of tagged proteins and high-speed in vivo confocal imaging was used to quantify intraflagellar transport (IFT) and IFT particle localization within multiciliated cells of the Xenopus epidermis. RESULTS The au5 mutants possess a nonsense mutation in cluap1, which encodes a component of the IFT machinery. Photoreceptor defects result from degeneration of photoreceptors, and defects in ciliogenesis precede degeneration. Cilia in the olfactory pit are absent, and left-right heart positioning is aberrant, consistent with a role for cluap1 during ciliogenesis and cilia-dependent development. High-speed in vivo imaging demonstrates that cluap1 undergoes IFT and that it moves along the cilium bidirectionally, with similar localization and kinetics as IFT20, an IFT-B complex component. CONCLUSIONS We identified a novel mutation in cluap1 and determined that photoreceptor maintenance is dependent on cluap1. Imaging data support a model in which cluap1 is a component of the IFT-B complex, and cilia formation requires cluap1 function. These data may provide new insights into the mechanism of photoreceptor degeneration in retinal ciliopathies.
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Affiliation(s)
- Chanjae Lee
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States
| | - John B Wallingford
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States Howard Hughes Medical Institute, The University of Texas at Austin, Austin, Texas, United States
| | - Jeffrey M Gross
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States
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Tuz K, Bachmann-Gagescu R, O'Day DR, Hua K, Isabella CR, Phelps IG, Stolarski AE, O'Roak BJ, Dempsey JC, Lourenco C, Alswaid A, Bönnemann CG, Medne L, Nampoothiri S, Stark Z, Leventer RJ, Topçu M, Cansu A, Jagadeesh S, Done S, Ishak GE, Glass IA, Shendure J, Neuhauss SCF, Haldeman-Englert CR, Doherty D, Ferland RJ. Mutations in CSPP1 cause primary cilia abnormalities and Joubert syndrome with or without Jeune asphyxiating thoracic dystrophy. Am J Hum Genet 2014; 94:62-72. [PMID: 24360808 DOI: 10.1016/j.ajhg.2013.11.019] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 11/13/2013] [Indexed: 12/26/2022] Open
Abstract
Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown.
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Affiliation(s)
- Karina Tuz
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY 12208, USA
| | - Ruxandra Bachmann-Gagescu
- Institute of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland; Institute of Medical Genetics, University of Zurich, 8603 Zurich, Switzerland
| | - Diana R O'Day
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Kiet Hua
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY 12208, USA
| | - Christine R Isabella
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Ian G Phelps
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Allan E Stolarski
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY 12208, USA
| | - Brian J O'Roak
- Department of Molecular & Medical Genetics, Oregon Health Sciences University, Portland, OR 97239, USA
| | - Jennifer C Dempsey
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Charles Lourenco
- Neurogenetics Division, Clinics Hospital, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Abdulrahman Alswaid
- Department of Pediatrics, King Abdulaziz Medical City, Riyadh 11426, Saudi Arabia
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, John Edward Porter Neuroscience Research Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Livija Medne
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences and Research Center, AIMS Ponekkara Post Office, Kochi, Kerala 682041, India
| | - Zornitza Stark
- Victorian Clinical Genetics Services, Murdoch Childrens Research Institute, Parkville, VIC 3052, Australia
| | - Richard J Leventer
- Departments of Neurology and Pediatrics, Murdoch Childrens Research Institute, Royal Children's Hospital and University of Melbourne, Parkville, VIC 3052, Australia
| | - Meral Topçu
- Department of Child Neurology, Hacettepe University Medical Faculty, Ihsan Dogramacı Children's Hospital, Ankara 06100, Turkey
| | - Ali Cansu
- Pediatric Neurology Unit, De Karadeniz Technical University, Trabzon 61080, Turkey
| | | | - Stephen Done
- Department of Radiology, University of Washington and Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Gisele E Ishak
- Department of Radiology, University of Washington and Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Ian A Glass
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Integrative Brain Research, Seattle Children's Hospital Research Institute, Seattle, WA 98105, USA
| | - Jay Shendure
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Stephan C F Neuhauss
- Institute of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Chad R Haldeman-Englert
- Department of Pediatrics, Section on Medical Genetics, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Dan Doherty
- Divisions of Genetic Medicine and Developmental Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Integrative Brain Research, Seattle Children's Hospital Research Institute, Seattle, WA 98105, USA.
| | - Russell J Ferland
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY 12208, USA; Department of Neurology, Albany Medical College, Albany, NY 12208, USA.
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Development of an automated imaging pipeline for the analysis of the zebrafish larval kidney. PLoS One 2013; 8:e82137. [PMID: 24324758 PMCID: PMC3852951 DOI: 10.1371/journal.pone.0082137] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 10/21/2013] [Indexed: 01/01/2023] Open
Abstract
The analysis of kidney malformation caused by environmental influences during nephrogenesis or by hereditary nephropathies requires animal models allowing the in vivo observation of developmental processes. The zebrafish has emerged as a useful model system for the analysis of vertebrate organ development and function, and it is suitable for the identification of organotoxic or disease-modulating compounds on a larger scale. However, to fully exploit its potential in high content screening applications, dedicated protocols are required allowing the consistent visualization of inner organs such as the embryonic kidney. To this end, we developed a high content screening compatible pipeline for the automated imaging of standardized views of the developing pronephros in zebrafish larvae. Using a custom designed tool, cavities were generated in agarose coated microtiter plates allowing for accurate positioning and orientation of zebrafish larvae. This enabled the subsequent automated acquisition of stable and consistent dorsal views of pronephric kidneys. The established pipeline was applied in a pilot screen for the analysis of the impact of potentially nephrotoxic drugs on zebrafish pronephros development in the Tg(wt1b:EGFP) transgenic line in which the developing pronephros is highlighted by GFP expression. The consistent image data that was acquired allowed for quantification of gross morphological pronephric phenotypes, revealing concentration dependent effects of several compounds on nephrogenesis. In addition, applicability of the imaging pipeline was further confirmed in a morpholino based model for cilia-associated human genetic disorders associated with different intraflagellar transport genes. The developed tools and pipeline can be used to study various aspects in zebrafish kidney research, and can be readily adapted for the analysis of other organ systems.
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49
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Halbritter J, Bizet A, Schmidts M, Porath J, Braun D, Gee H, McInerney-Leo A, Krug P, Filhol E, Davis E, Airik R, Czarnecki P, Lehman A, Trnka P, Nitschké P, Bole-Feysot C, Schueler M, Knebelmann B, Burtey S, Szabó A, Tory K, Leo P, Gardiner B, McKenzie F, Zankl A, Brown M, Hartley J, Maher E, Li C, Leroux M, Scambler P, Zhan S, Jones S, Kayserili H, Tuysuz B, Moorani K, Constantinescu A, Krantz I, Kaplan B, Shah J, Hurd T, Doherty D, Katsanis N, Duncan E, Otto E, Beales P, Mitchison H, Saunier S, Hildebrandt F. Defects in the IFT-B component IFT172 cause Jeune and Mainzer-Saldino syndromes in humans. Am J Hum Genet 2013; 93:915-25. [PMID: 24140113 PMCID: PMC3824130 DOI: 10.1016/j.ajhg.2013.09.012] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 09/06/2013] [Accepted: 09/24/2013] [Indexed: 01/09/2023] Open
Abstract
Intraflagellar transport (IFT) depends on two evolutionarily conserved modules, subcomplexes A (IFT-A) and B (IFT-B), to drive ciliary assembly and maintenance. All six IFT-A components and their motor protein, DYNC2H1, have been linked to human skeletal ciliopathies, including asphyxiating thoracic dystrophy (ATD; also known as Jeune syndrome), Sensenbrenner syndrome, and Mainzer-Saldino syndrome (MZSDS). Conversely, the 14 subunits in the IFT-B module, with the exception of IFT80, have unknown roles in human disease. To identify additional IFT-B components defective in ciliopathies, we independently performed different mutation analyses: candidate-based sequencing of all IFT-B-encoding genes in 1,467 individuals with a nephronophthisis-related ciliopathy or whole-exome resequencing in 63 individuals with ATD. We thereby detected biallelic mutations in the IFT-B-encoding gene IFT172 in 12 families. All affected individuals displayed abnormalities of the thorax and/or long bones, as well as renal, hepatic, or retinal involvement, consistent with the diagnosis of ATD or MZSDS. Additionally, cerebellar aplasia or hypoplasia characteristic of Joubert syndrome was present in 2 out of 12 families. Fibroblasts from affected individuals showed disturbed ciliary composition, suggesting alteration of ciliary transport and signaling. Knockdown of ift172 in zebrafish recapitulated the human phenotype and demonstrated a genetic interaction between ift172 and ift80. In summary, we have identified defects in IFT172 as a cause of complex ATD and MZSDS. Our findings link the group of skeletal ciliopathies to an additional IFT-B component, IFT172, similar to what has been shown for IFT-A.
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Affiliation(s)
- Jan Halbritter
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Albane A. Bizet
- Institut National de la Santé et de la Recherche Médicale U-983, Necker Hospital, 75015 Paris, France
- Paris Descartes University, Sorbonne Paris Cité, Imagine Institute, 75015 Paris, France
| | - Miriam Schmidts
- Molecular Medicine Unit and Birth Defects Research Centre, University College London Institute of Child Health, London, WC1N 1EH, UK
| | - Jonathan D. Porath
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Daniela A. Braun
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Heon Yung Gee
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Aideen M. McInerney-Leo
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
| | - Pauline Krug
- Institut National de la Santé et de la Recherche Médicale U-983, Necker Hospital, 75015 Paris, France
- Paris Descartes University, Sorbonne Paris Cité, Imagine Institute, 75015 Paris, France
| | - Emilie Filhol
- Institut National de la Santé et de la Recherche Médicale U-983, Necker Hospital, 75015 Paris, France
- Paris Descartes University, Sorbonne Paris Cité, Imagine Institute, 75015 Paris, France
| | - Erica E. Davis
- Center for Human Disease Modeling, Duke University, Durham, NC 27710, USA
| | - Rannar Airik
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Peter G. Czarnecki
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Harvard-MIT Health Sciences and Technology, Boston, MA 02139, USA
| | - Anna M. Lehman
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V6H 3N1, Canada
| | - Peter Trnka
- School of Paediatrics and Child Health, The University of Queensland, Herston, QLD 4029, Australia
| | - Patrick Nitschké
- Bioinformatic Platform, Paris Descartes University, Sorbonne Paris Cité, 75270 Paris, France
| | | | - Markus Schueler
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Bertrand Knebelmann
- Department of Nephrology, Necker Hospital, Assistance Publique – Hôpitaux de Paris, 75015 Paris, France
| | - Stéphane Burtey
- Centre de Néphrologie et Transplantation Rénale, Hôpital de la Conception, Marseille 13005, France
| | - Attila J. Szabó
- 1 Department of Pediatrics, Semmelweis University, 1083 Budapest, Hungary
| | - Kálmán Tory
- Institut National de la Santé et de la Recherche Médicale U-983, Necker Hospital, 75015 Paris, France
- 1 Department of Pediatrics, Semmelweis University, 1083 Budapest, Hungary
| | - Paul J. Leo
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
| | - Brooke Gardiner
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
| | - Fiona A. McKenzie
- Genetic Services of Western Australia, Subiaco, WA 6008, Australia
- School of Paediatrics and Child Health, The University of Western Australia, Crawley, WA 6009, Australia
| | - Andreas Zankl
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
- UQ Centre for Clinical Research, The University of Queensland, Herston, QLD 4029, Australia
- Genetic Medicine, The University of Sydney, Sydney, NSW 2006, Australia
- Academic Department of Medical Genetics, The Children’s Hospital at Westmead, Sydney, NSW 2145, Australia
| | - Matthew A. Brown
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
| | | | - Eamonn R. Maher
- Centre for Rare Diseases and Personalised Medicine, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Department of Medical Genetics, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK
| | - Chunmei Li
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Michel R. Leroux
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Peter J. Scambler
- Molecular Medicine Unit and Birth Defects Research Centre, University College London Institute of Child Health, London, WC1N 1EH, UK
| | - Shing H. Zhan
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, BC V5Z 4S6, Canada
| | - Steven J. Jones
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V6H 3N1, Canada
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, BC V5Z 4S6, Canada
| | - Hülya Kayserili
- Medical Genetics Department, Istanbul Medical Faculty, Istanbul University, Istanbul 34093, Turkey
| | - Beyhan Tuysuz
- Division of Pediatric Genetics, Department of Pediatrics, Cerrahpasa Medical School, Istanbul University, Istanbul 34098, Turkey
| | - Khemchand N. Moorani
- Department of Paediatric Nephrology, National Institute of Child Health, Karachi 75510, Pakistan
| | | | - Ian D. Krantz
- Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Bernard S. Kaplan
- Division of Nephrology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104-4399, USA
| | - Jagesh V. Shah
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Health Sciences and Technology, Boston, MA 02139, USA
- Renal Medicine, Brigham and Women’s Hospital, Boston, MA 02215, USA
| | | | - Toby W. Hurd
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dan Doherty
- Department of Pediatrics, University of Washington, Seattle, WA 98195-6320, USA
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University, Durham, NC 27710, USA
| | - Emma L. Duncan
- Translational Research Institute, The University of Queensland Diamantina Institute, Level 7, 37 Kent Street, Woolloongabba, QLD 4102, Australia
- School of Paediatrics and Child Health, The University of Western Australia, Crawley, WA 6009, Australia
- Department of Endocrinology, Royal Brisbane and Women’s Hospital, James Mayne Building, Butterfield Road, Herston, QLD 4029, Australia
| | - Edgar A. Otto
- Department of Pediatrics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Philip L. Beales
- Molecular Medicine Unit and Birth Defects Research Centre, University College London Institute of Child Health, London, WC1N 1EH, UK
| | - Hannah M. Mitchison
- Molecular Medicine Unit and Birth Defects Research Centre, University College London Institute of Child Health, London, WC1N 1EH, UK
| | - Sophie Saunier
- Institut National de la Santé et de la Recherche Médicale U-983, Necker Hospital, 75015 Paris, France
- Paris Descartes University, Sorbonne Paris Cité, Imagine Institute, 75015 Paris, France
| | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
- Howard Hughes Medical Institute
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50
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Wang J, Deretic D. Molecular complexes that direct rhodopsin transport to primary cilia. Prog Retin Eye Res 2013; 38:1-19. [PMID: 24135424 DOI: 10.1016/j.preteyeres.2013.08.004] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 08/13/2013] [Accepted: 08/19/2013] [Indexed: 11/27/2022]
Abstract
Rhodopsin is a key molecular constituent of photoreceptor cells, yet understanding of how it regulates photoreceptor membrane trafficking and biogenesis of light-sensing organelles, the rod outer segments (ROS) is only beginning to emerge. Recently identified sequence of well-orchestrated molecular interactions of rhodopsin with the functional networks of Arf and Rab GTPases at multiple stages of intracellular targeting fits well into the complex framework of the biogenesis and maintenance of primary cilia, of which the ROS is one example. This review will discuss the latest progress in dissecting the molecular complexes that coordinate rhodopsin incorporation into ciliary-targeted carriers with the recruitment and activation of membrane tethering complexes and regulators of fusion with the periciliary plasma membrane. In addition to revealing the fundamental principals of ciliary membrane renewal, recent advances also provide molecular insight into the ways by which disruptions of the exquisitely orchestrated interactions lead to cilia dysfunction and result in human retinal dystrophies and syndromic diseases that affect multiple organs, including the eyes.
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Affiliation(s)
- Jing Wang
- Department of Surgery, Division of Ophthalmology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Dusanka Deretic
- Department of Surgery, Division of Ophthalmology, University of New Mexico, Albuquerque, NM 87131, USA; Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM 87131, USA.
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