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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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2
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Devlin LA, Ramsbottom SA, Overman LM, Lisgo SN, Clowry G, Molinari E, Powell L, Miles CG, Sayer JA. Embryonic and foetal expression patterns of the ciliopathy gene CEP164. PLoS One 2020; 15:e0221914. [PMID: 31990917 PMCID: PMC6986751 DOI: 10.1371/journal.pone.0221914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 01/03/2020] [Indexed: 01/20/2023] Open
Abstract
Nephronophthisis-related ciliopathies (NPHP-RC) are a group of inherited genetic disorders that share a defect in the formation, maintenance or functioning of the primary cilium complex, causing progressive cystic kidney disease and other clinical manifestations. Mutations in centrosomal protein 164 kDa (CEP164), also known as NPHP15, have been identified as a cause of NPHP-RC. Here we have utilised the MRC-Wellcome Trust Human Developmental Biology Resource (HDBR) to perform immunohistochemistry studies on human embryonic and foetal tissues to determine the expression patterns of CEP164 during development. Notably expression is widespread, yet defined, in multiple organs including the kidney, retina and cerebellum. Murine studies demonstrated an almost identical Cep164 expression pattern. Taken together, these data support a conserved role for CEP164 throughout the development of numerous organs, which, we suggest, accounts for the multi-system disease phenotype of CEP164-mediated NPHP-RC.
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Affiliation(s)
- L. A. Devlin
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
| | - S. A. Ramsbottom
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
| | - L. M. Overman
- MRC-Wellcome Trust Human Developmental Biology Resource, Institute of Genetic Medicine, International Centre for Life, Newcastle upon Tyne, England, United Kingdom
| | - S. N. Lisgo
- MRC-Wellcome Trust Human Developmental Biology Resource, Institute of Genetic Medicine, International Centre for Life, Newcastle upon Tyne, England, United Kingdom
| | - G. Clowry
- Institute of Neuroscience, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, England, United Kingdom
| | - E. Molinari
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
| | - L. Powell
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
| | - C. G. Miles
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
| | - J. A. Sayer
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, England, United Kingdom
- The Newcastle upon Tyne Hospitals NHS Foundation Trust, Freeman Road, Newcastle upon Tyne, England, United Kingdom
- National Institute for Health Research Newcastle Biomedical Research Centre, Newcastle upon Tyne, England, United Kingdom
- * E-mail:
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3
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Doan RN, Lim ET, De Rubeis S, Betancur C, Cutler DJ, Chiocchetti AG, Overman LM, Soucy A, Goetze S, Freitag CM, Daly MJ, Walsh CA, Buxbaum JD, Yu TW. Recessive gene disruptions in autism spectrum disorder. Nat Genet 2019; 51:1092-1098. [PMID: 31209396 PMCID: PMC6629034 DOI: 10.1038/s41588-019-0433-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 05/02/2019] [Indexed: 01/27/2023]
Abstract
Autism spectrum disorder (ASD) affects up to 1 in 59 individuals1. Genome-wide association and large-scale sequencing studies strongly implicate both common variants2-4 and rare de novo variants5-10 in ASD. Recessive mutations have also been implicated11-14 but their contribution remains less well defined. Here we demonstrate an excess of biallelic loss-of-function and damaging missense mutations in a large ASD cohort, corresponding to approximately 5% of total cases, including 10% of females, consistent with a female protective effect. We document biallelic disruption of known or emerging recessive neurodevelopmental genes (CA2, DDHD1, NSUN2, PAH, RARB, ROGDI, SLC1A1, USH2A) as well as other genes not previously implicated in ASD including FEV (FEV transcription factor, ETS family member), which encodes a key regulator of the serotonergic circuitry. Our data refine estimates of the contribution of recessive mutation to ASD and suggest new paths for illuminating previously unknown biological pathways responsible for this condition.
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Affiliation(s)
- Ryan N Doan
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Elaine T Lim
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Catalina Betancur
- Neuroscience Paris Seine, Institut de Biologie Paris Seine, Sorbonne Université, INSERM, CNRS, Paris, France
| | - David J Cutler
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Andreas G Chiocchetti
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Autism Research and Intervention Center of Excellence, University Hospital Frankfurt, Goethe University, Frankfurt, Germany
| | - Lynne M Overman
- Human Developmental Biology Resource, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Newcastle-upon-Tyne, UK
| | - Aubrie Soucy
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
| | - Susanne Goetze
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
| | - Christine M Freitag
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Autism Research and Intervention Center of Excellence, University Hospital Frankfurt, Goethe University, Frankfurt, Germany
| | - Mark J Daly
- Harvard Medical School, Boston, MA, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Center for Human Genetic Research, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Christopher A Walsh
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Joseph D Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Timothy W Yu
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
- The Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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Kuhlwilm M, Boeckx C. A catalog of single nucleotide changes distinguishing modern humans from archaic hominins. Sci Rep 2019; 9:8463. [PMID: 31186485 PMCID: PMC6560109 DOI: 10.1038/s41598-019-44877-x] [Citation(s) in RCA: 40] [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: 01/31/2019] [Accepted: 05/24/2019] [Indexed: 01/06/2023] Open
Abstract
Throughout the past decade, studying ancient genomes has provided unique insights into human prehistory, and differences between modern humans and other branches like Neanderthals can enrich our understanding of the molecular basis of unique modern human traits. Modern human variation and the interactions between different hominin lineages are now well studied, making it reasonable to go beyond fixed genetic changes and explore changes that are observed at high frequency in present-day humans. Here, we identify 571 genes with non-synonymous changes at high frequency. We suggest that molecular mechanisms in cell division and networks affecting cellular features of neurons were prominently modified by these changes. Complex phenotypes in brain growth trajectory and cognitive traits are likely influenced by these networks and other non-coding changes presented here. We propose that at least some of these changes contributed to uniquely human traits, and should be prioritized for experimental validation.
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Affiliation(s)
- Martin Kuhlwilm
- Institut de Biologia Evolutiva, (CSIC-Universitat Pompeu Fabra), PRBB, Barcelona, Spain
| | - Cedric Boeckx
- ICREA, Barcelona, Spain.
- University of Barcelona, Barcelona, Spain.
- UB Institute of Complex Systems, Barcelona, Spain.
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Baehr W, Hanke-Gogokhia C, Sharif A, Reed M, Dahl T, Frederick JM, Ying G. Insights into photoreceptor ciliogenesis revealed by animal models. Prog Retin Eye Res 2018; 71:26-56. [PMID: 30590118 DOI: 10.1016/j.preteyeres.2018.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 12/10/2018] [Accepted: 12/18/2018] [Indexed: 12/11/2022]
Abstract
Photoreceptors are polarized neurons, with very specific subcellular compartmentalization and unique requirements for protein expression and trafficking. Each photoreceptor contains an outer segment, the site of photon capture that initiates vision, an inner segment that houses the biosynthetic machinery and a synaptic terminal for signal transmission to downstream neurons. Outer segments and inner segments are connected by a connecting cilium (CC), the equivalent of a transition zone (TZ) of primary cilia. The connecting cilium is part of the basal body/axoneme backbone that stabilizes the outer segment. This report will update the reader on late developments in photoreceptor ciliogenesis and transition zone formation, specifically in mouse photoreceptors, focusing on early events in photoreceptor ciliogenesis. The connecting cilium, an elongated and narrow structure through which all outer segment proteins and membrane components must traffic, functions as a gate that controls access to the outer segment. Here we will review genes and their protein products essential for basal body maturation and for CC/TZ genesis, sorted by phenotype. Emphasis is given to naturally occurring mouse mutants and gene knockouts that interfere with CC/TZ formation and ciliogenesis.
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Affiliation(s)
- Wolfgang Baehr
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA.
| | - Christin Hanke-Gogokhia
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Ali Sharif
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Michelle Reed
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Tiffanie Dahl
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Jeanne M Frederick
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
| | - Guoxin Ying
- Department of Ophthalmology and Visual Sciences, University of Utah Health Sciences, Salt Lake City, UT, 84132, USA
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6
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Levchenko A, Kanapin A, Samsonova A, Gainetdinov RR. Human Accelerated Regions and Other Human-Specific Sequence Variations in the Context of Evolution and Their Relevance for Brain Development. Genome Biol Evol 2018; 10:166-188. [PMID: 29149249 PMCID: PMC5767953 DOI: 10.1093/gbe/evx240] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2017] [Indexed: 12/24/2022] Open
Abstract
The review discusses, in a format of a timeline, the studies of different types of genetic variants, present in Homo sapiens, but absent in all other primate, mammalian, or vertebrate species, tested so far. The main characteristic of these variants is that they are found in regions of high evolutionary conservation. These sequence variations include single nucleotide substitutions (called human accelerated regions), deletions, and segmental duplications. The rationale for finding such variations in the human genome is that they could be responsible for traits, specific to our species, of which the human brain is the most remarkable. As became obvious, the vast majority of human-specific single nucleotide substitutions are found in noncoding, likely regulatory regions. A number of genes, associated with these human-specific alleles, often through novel enhancer activity, were in fact shown to be implicated in human-specific development of certain brain areas, including the prefrontal cortex. Human-specific deletions may remove regulatory sequences, such as enhancers. Segmental duplications, because of their large size, create new coding sequences, like new functional paralogs. Further functional study of these variants will shed light on evolution of our species, as well as on the etiology of neurodevelopmental disorders.
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Affiliation(s)
- Anastasia Levchenko
- Institute of Translational Biomedicine, Saint Petersburg State University, Russia
| | - Alexander Kanapin
- Institute of Translational Biomedicine, Saint Petersburg State University, Russia
- Department of Oncology, University of Oxford, United Kingdom
| | - Anastasia Samsonova
- Institute of Translational Biomedicine, Saint Petersburg State University, Russia
- Department of Oncology, University of Oxford, United Kingdom
| | - Raul R Gainetdinov
- Institute of Translational Biomedicine, Saint Petersburg State University, Russia
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow, Russia
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7
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Alterations in the expression of a neurodevelopmental gene exert long-lasting effects on cognitive-emotional phenotypes and functional brain networks: translational evidence from the stress-resilient Ahi1 knockout mouse. Mol Psychiatry 2017; 22:884-899. [PMID: 27021817 PMCID: PMC5444025 DOI: 10.1038/mp.2016.29] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 12/29/2015] [Accepted: 02/03/2016] [Indexed: 12/19/2022]
Abstract
Many psychiatric disorders are highly heritable and may represent the clinical outcome of early aberrations in the formation of neural networks. The placement of brain connectivity as an 'intermediate phenotype' renders it an attractive target for exploring its interaction with genomics and behavior. Given the complexity of genetic make up and phenotypic heterogeneity in humans, translational studies are indicated. Recently, we demonstrated that a mouse model with heterozygous knockout of the key neurodevelopmental gene Ahi1 displays a consistent stress-resilient phenotype. Extending these data, the current research describes our multi-faceted effort to link early variations in Ahi1 expression with long-term consequences for functional brain networks and cognitive-emotional phenotypes. By combining behavioral paradigms with graph-based analysis of whole-brain functional networks, and then cross-validating the data with robust neuroinformatic data sets, our research suggests that physiological variation in gene expression during neurodevelopment is eventually translated into a continuum of global network metrics that serve as intermediate phenotypes. Within this framework, we suggest that organization of functional brain networks may result, in part, from an adaptive trade-off between efficiency and resilience, ultimately culminating in a phenotypic diversity that encompasses dimensions such as emotional regulation and cognitive function.
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Salva I, Albuquerque C, Moreira A, Dâmaso C. Nystagmus in a newborn: a manifestation of Joubert syndrome in the neonatal period. BMJ Case Rep 2016; 2016:bcr-2015-213127. [PMID: 26759440 DOI: 10.1136/bcr-2015-213127] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Joubert syndrome is a rare disorder, usually autosomal recessive, with a prevalence of 1:80,000 to 1:100,000. This disease presents most commonly as breathing irregularities, although the two major clinical criteria are hypotonia and developmental delay, sometimes associated with ocular movement abnormalities. The severity of the presentation varies, ranging from mild cases with normal intelligence to severe developmental delays associated with early death. We report a case of a newborn who presented to the emergency department for absent ocular fixation and torsional nystagmus without other neurological abnormalities. Her cranial MR showed cerebellar vermis agenesis and a molar tooth sign. Her laboratory evaluation, and renal and abdominal ultrasound were normal. An electroretinogram showed mixed retinal dystrophy and an AHI1 homozygous missense c.1981T>C mutation was identified (parents are carriers). Throughout infancy, she has shown mild developmental delay and hypotonia, but no respiratory abnormalities. Owing to variable expressivity, a high level of suspicion is required.
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Affiliation(s)
- Inês Salva
- Department of Pediatrics, Hospital de Dona Estefânia, Lisbon, Portugal
| | | | - Ana Moreira
- Hospital de Dona Estefânia, Lisbon, Portugal
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9
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Thomas S, Cantagrel V, Mariani L, Serre V, Lee JE, Elkhartoufi N, de Lonlay P, Desguerre I, Munnich A, Boddaert N, Lyonnet S, Vekemans M, Lisgo SN, Caspary T, Gleeson J, Attié-Bitach T. Identification of a novel ARL13B variant in a Joubert syndrome-affected patient with retinal impairment and obesity. Eur J Hum Genet 2015; 23:621-7. [PMID: 25138100 PMCID: PMC4402632 DOI: 10.1038/ejhg.2014.156] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 06/27/2014] [Accepted: 07/09/2014] [Indexed: 12/29/2022] Open
Abstract
Joubert syndrome (JS) is a genetically heterogeneous autosomal recessive ciliopathy with 22 genes implicated to date, including a small, ciliary GTPase, ARL13B. ARL13B is required for cilia formation in vertebrates. JS patients display multiple symptoms characterized by ataxia due to the cerebellar vermis hypoplasia, and that can also include ocular abnormalities, renal cysts, liver fibrosis or polydactyly. These symptoms are shared with other ciliopathies, some of which display additional phenotypes, such as obesity. Here we identified a novel homozygous missense variant in ARL13B/JBTS8 in a JS patient who displayed retinal defects and obesity. We demonstrate the variant disrupts ARL13B function, as its expression did not rescue the mutant phenotype either in Arl13b(scorpion) zebrafish or in Arl13b(hennin) mouse embryonic fibroblasts, while the wild-type ARL13B did. Finally, we show that ARL13B is localized within the primary cilia of neonatal mouse hypothalamic neurons consistent with the known link between hypothalamic ciliary function and obesity. Thus our data identify a novel ARL13B variant that causes JS and retinopathy and suggest an extension of the phenotypic spectrum of ARL13B mutations to obesity.
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Affiliation(s)
- Sophie Thomas
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
| | - Vincent Cantagrel
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Laboratory of Neurogenetics, Howard Hughes Medical Institute, Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Laura Mariani
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Valérie Serre
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- UMR7592CNRS, Jacques Monod Institute, Paris Diderot University, Paris, France
| | - Ji-Eun Lee
- Laboratory of Neurogenetics, Howard Hughes Medical Institute, Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Nadia Elkhartoufi
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Pascale de Lonlay
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Isabelle Desguerre
- Service de neurométabolisme, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Arnold Munnich
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Nathalie Boddaert
- Radiologie Pédiatrique et INSERM U-797, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Stanislas Lyonnet
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Michel Vekemans
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Steven N Lisgo
- The MRC-Wellcome Trust Human Developmental Biology Resource (HDBR), Institute of Genetic Medicine, International Centre for Life, Central Parkway, Newcastle Upon Tyne, UK
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Joseph Gleeson
- Laboratory of Neurogenetics, Howard Hughes Medical Institute, Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Tania Attié-Bitach
- INSERM U1163, Hôpital Necker-Enfants Malades, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France
- Département de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
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10
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Murine Joubert syndrome reveals Hedgehog signaling defects as a potential therapeutic target for nephronophthisis. Proc Natl Acad Sci U S A 2014; 111:9893-8. [PMID: 24946806 DOI: 10.1073/pnas.1322373111] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Nephronophthisis (NPHP) is the major cause of pediatric renal failure, yet the disease remains poorly understood, partly due to the lack of appropriate animal models. Joubert syndrome (JBTS) is an inherited ciliopathy giving rise to NPHP with cerebellar vermis aplasia and retinal degeneration. Among patients with JBTS and a cerebello-oculo-renal phenotype, mutations in CEP290 (NPHP6) are the most common genetic lesion. We present a Cep290 gene trap mouse model of JBTS that displays the kidney, eye, and brain abnormalities that define the syndrome. Mutant mice present with cystic kidney disease as neonates. Newborn kidneys contain normal amounts of lymphoid enhancer-binding factor 1 (Lef1) and transcription factor 1 (Tcf1) protein, indicating normal function of the Wnt signaling pathway; however, an increase in the protein Gli3 repressor reveals abnormal Hedgehog (Hh) signaling evident in newborn kidneys. Collecting duct cells from mutant mice have abnormal primary cilia and are unable to form spheroid structures in vitro. Treatment of mutant cells with the Hh agonist purmorphamine restored normal spheroid formation. Renal epithelial cells from a JBTS patient with CEP290 mutations showed similar impairments to spheroid formation that could also be partially rescued by exogenous stimulation of Hh signaling. These data implicate abnormal Hh signaling as the cause of NPHP and suggest that Hh agonists may be exploited therapeutically.
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11
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Abstract
The primary cilium compartmentalizes a tiny fraction of the cell surface and volume, yet many proteins are highly enriched in this area and so efficient mechanisms are necessary to concentrate them in the ciliary compartment. Here we review mechanisms that are thought to deliver protein cargo to the base of cilia and are likely to interact with ciliary gating mechanisms. Given the immense variety of ciliary cytosolic and transmembrane proteins, it is almost certain that multiple, albeit frequently interconnected, pathways mediate this process. It is also clear that none of these pathways is fully understood at the present time. Mechanisms that are discussed below facilitate ciliary localization of structural and signaling molecules, which include receptors, G-proteins, ion channels, and enzymes. These mechanisms form a basis for every aspect of cilia function in early embryonic patterning, organ morphogenesis, sensory perception and elsewhere.
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Affiliation(s)
- Jarema Malicki
- MRC Centre for Developmental and Biomedical Genetics; Department of Biomedical Science; The University of Sheffield; Sheffield, UK
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12
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Lotan A, Lifschytz T, Slonimsky A, Broner EC, Greenbaum L, Abedat S, Fellig Y, Cohen H, Lory O, Goelman G, Lerer B. Neural mechanisms underlying stress resilience in Ahi1 knockout mice: relevance to neuropsychiatric disorders. Mol Psychiatry 2014; 19:243-52. [PMID: 24042478 DOI: 10.1038/mp.2013.123] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 07/19/2013] [Accepted: 08/08/2013] [Indexed: 02/06/2023]
Abstract
The Abelson helper integration site 1 (AHI1) gene has a pivotal role in brain development. Studies by our group and others have demonstrated association of AHI1 with schizophrenia and autism. To elucidate the mechanism whereby alteration in AHI1 expression may be implicated in the pathogenesis of neuropsychiatric disorders, we studied Ahi1 heterozygous knockout (Ahi1(+/-)) mice. Although their performance was not different from wild-type mice on tests that model classical schizophrenia-related endophenotypes, Ahi1(+/-) mice displayed an anxiolytic-like phenotype across different converging modalities. Using behavioral paradigms that involve exposure to environmental and social stress, significantly decreased anxiety was evident in the open field, elevated plus maze and dark-light box, as well as during social interaction in pairs. Assessment of core temperature and corticosterone secretion revealed a significantly blunted response of the autonomic nervous system and the hypothalamic-pituitary-adrenal axis in Ahi1(+/-) mice exposed to environmental and visceral stress. However, response to centrally acting anxiogenic compounds was intact. On resting-state functional MRI, connectivity of the amygdala with other brain regions involved in processing of anxiogenic stimuli and inhibitory avoidance learning, such as the lateral entorhinal cortex, ventral hippocampus and ventral tegmental area, was significantly reduced in the mutant mice. Taken together, our data link Ahi1 under-expression with a defect in the process of threat detection. Alternatively, the results could be interpreted as representing an anxiety-related endophenotype, possibly granting the Ahi1(+/-) mouse relative resilience to various types of stress. The current knockout model highlights the contribution of translational approaches to understanding the genetic basis of emotional regulation and its associated neurocircuitry, with possible relevance to neuropsychiatric disorders.
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Affiliation(s)
- A Lotan
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - T Lifschytz
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - A Slonimsky
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - E C Broner
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - L Greenbaum
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - S Abedat
- Cardiovascular Research Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Y Fellig
- Department of Pathology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - H Cohen
- Anxiety and Stress Research Unit, Ben-Gurion University of the Negev, Beersheba, Israel
| | - O Lory
- MRI Lab, Medical Biophysics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - G Goelman
- MRI Lab, Medical Biophysics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - B Lerer
- Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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13
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Hall EA, Keighren M, Ford MJ, Davey T, Jarman AP, Smith LB, Jackson IJ, Mill P. Acute versus chronic loss of mammalian Azi1/Cep131 results in distinct ciliary phenotypes. PLoS Genet 2013; 9:e1003928. [PMID: 24415959 PMCID: PMC3887133 DOI: 10.1371/journal.pgen.1003928] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 09/14/2013] [Indexed: 01/20/2023] Open
Abstract
Defects in cilium and centrosome function result in a spectrum of clinically-related disorders, known as ciliopathies. However, the complex molecular composition of these structures confounds functional dissection of what any individual gene product is doing under normal and disease conditions. As part of an siRNA screen for genes involved in mammalian ciliogenesis, we and others have identified the conserved centrosomal protein Azi1/Cep131 as required for cilia formation, supporting previous Danio rerio and Drosophila melanogaster mutant studies. Acute loss of Azi1 by knock-down in mouse fibroblasts leads to a robust reduction in ciliogenesis, which we rescue by expressing siRNA-resistant Azi1-GFP. Localisation studies show Azi1 localises to centriolar satellites, and traffics along microtubules becoming enriched around the basal body. Azi1 also localises to the transition zone, a structure important for regulating traffic into the ciliary compartment. To study the requirement of Azi1 during development and tissue homeostasis, Azi1 null mice were generated (Azi1Gt/Gt). Surprisingly, Azi1Gt/Gt MEFs have no discernible ciliary phenotype and moreover are resistant to Azi1 siRNA knock-down, demonstrating that a compensation mechanism exists to allow ciliogenesis to proceed despite the lack of Azi1. Cilia throughout Azi1 null mice are functionally normal, as embryonic patterning and adult homeostasis are grossly unaffected. However, in the highly specialised sperm flagella, the loss of Azi1 is not compensated, leading to striking microtubule-based trafficking defects in both the manchette and the flagella, resulting in male infertility. Our analysis of Azi1 knock-down (acute loss) versus gene deletion (chronic loss) suggests that Azi1 plays a conserved, but non-essential trafficking role in ciliogenesis. Importantly, our in vivo analysis reveals Azi1 mediates novel trafficking functions necessary for flagellogenesis. Our study highlights the importance of both acute removal of a protein, in addition to mouse knock-out studies, when functionally characterising candidates for human disease. Cilia are slender projections from the surface of most mammalian cells and have sensory and sometimes motile functions. They are essential for mammalian development and defects in cilia lead to a group of human diseases, termed ciliopathies, with variable symptoms including embryonic lethality, lung and kidney defects, blindness and infertility. Cilia are complex structures composed of hundreds of components, whose individual functions are poorly understood. We screened for mammalian genes important in building cilia, and identified Azi1/Cep131, a gene previously shown to be required for cilia formation and function in fish and flies. We show that if we acutely reduce levels of Azi1 in mouse cells, fewer cells form cilia, but if we generate cells chronically lacking all Azi1, cilia form normally. In addition, mice without any Azi1 are healthy and viable, confirming normal cilia function. However, in these mice, the highly specialised ciliary structure of the sperm tail does not form, resulting in male infertility. We suggest Azi1 has conserved trafficking roles in both primary cilia and the specialised sperm flagella. Abruptly removing Azi1 results in instability causing the existing cilia network to collapse, whereas chronic deletion of Azi1 allows the system to re-equilibrate, and cilia to form normally.
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Affiliation(s)
- Emma A. Hall
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Margaret Keighren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Matthew J. Ford
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Tracey Davey
- Electron Microscopy Research Services, Medical School, Newcastle University, Newcastle, United Kingdom
| | - Andrew P. Jarman
- Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Lee B. Smith
- MRC Centre for Reproductive Health, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom
| | - Ian J. Jackson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
- * E-mail: (IJJ); (PM)
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
- * E-mail: (IJJ); (PM)
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