101
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Baddeley D, Bewersdorf J. Biological Insight from Super-Resolution Microscopy: What We Can Learn from Localization-Based Images. Annu Rev Biochem 2018; 87:965-989. [PMID: 29272143 DOI: 10.1146/annurev-biochem-060815-014801] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Super-resolution optical imaging based on the switching and localization of individual fluorescent molecules [photoactivated localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM), etc.] has evolved remarkably over the last decade. Originally driven by pushing technological limits, it has become a tool of biological discovery. The initial demand for impressive pictures showing well-studied biological structures has been replaced by a need for quantitative, reliable data providing dependable evidence for specific unresolved biological hypotheses. In this review, we highlight applications that showcase this development, identify the features that led to their success, and discuss remaining challenges and difficulties. In this context, we consider the complex topic of defining resolution for this imaging modality and address some of the more common analytical methods used with this data.
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Affiliation(s)
- David Baddeley
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06520, USA; , .,Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | - Joerg Bewersdorf
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06520, USA; , .,Department of Biomedical Engineering, Yale University, New Haven, Connecticut 06520, USA
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102
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Weng RR, Yang TT, Huang CE, Chang CW, Wang WJ, Liao JC. Super-Resolution Imaging Reveals TCTN2 Depletion-Induced IFT88 Lumen Leakage and Ciliary Weakening. Biophys J 2018; 115:263-275. [PMID: 29866362 DOI: 10.1016/j.bpj.2018.04.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 04/07/2018] [Accepted: 04/23/2018] [Indexed: 11/28/2022] Open
Abstract
The primary cilium is an essential organelle mediating key signaling activities, such as sonic hedgehog signaling. The molecular composition of the ciliary compartment is distinct from that of the cytosol, with the transition zone (TZ) gated the ciliary base. The TZ is a packed and organized protein complex containing multiple ciliopathy-associated protein species. Tectonic 2 (TCTN2) is one of the TZ proteins in the vicinity of the ciliary membrane, and its mutation is associated with Meckel syndrome. Despite its importance in ciliopathies, the role of TCTN2 in ciliary structure and molecules remains unclear. Here, we created a CRISPR/Cas9 TCTN2 knockout human retinal pigment epithelial cell line and conducted quantitative analysis of geometric localization using both wide-field and super-resolution microscopy techniques. We found that TCTN2 depletion resulted in partial TZ damage, loss of ciliary membrane proteins, leakage of intraflagellar transport protein IFT88 toward the basal body lumen, and cilium shortening and curving. The basal body lumen occupancy of IFT88 was also observed in si-RPGRIP1L cells and cytochalasin-D-treated wild-type cells, suggesting varying lumen accessibility for intraflagellar transport proteins under different perturbed conditions. Our findings support two possible models for the lumen leakage of IFT88, i.e., a tip leakage model and a misregulation model. Together, our quantitative image analysis augmented by super-resolution microscopy facilitates the observation of structural destruction and molecular redistribution in TCTN2-/- cilia, shedding light on mechanistic understanding of TZ-protein-associated ciliopathies.
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Affiliation(s)
- Rueyhung Roc Weng
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - T Tony Yang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Chia-En Huang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Chih-Wei Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Won-Jing Wang
- Institute of Biochemistry and Molecular Biology, National Yang Ming University, Taipei, Taiwan
| | - Jung-Chi Liao
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan; Genome and Systems Biology Degree Program, National Taiwan University, Taipei, Taiwan.
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103
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Gao M, Maraspini R, Beutel O, Zehtabian A, Eickholt B, Honigmann A, Ewers H. Expansion Stimulated Emission Depletion Microscopy (ExSTED). ACS NANO 2018; 12:4178-4185. [PMID: 29672025 DOI: 10.1021/acsnano.8b00776] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Stimulated emission depletion (STED) microscopy is routinely used to resolve the ultrastructure of cells with a ∼10-fold higher resolution compared to diffraction limited imaging. While STED microscopy is based on preparing the excited state of fluorescent probes with light, the recently developed expansion microscopy (ExM) provides subdiffraction resolution by physically enlarging the sample before microscopy. The expansion of the fixed cells by cross-linking and swelling of hydrogels easily enlarges the sample ∼4-fold and hence increases the effective optical resolution by this factor. To overcome the current limits of these complementary approaches, we combined ExM with STED (ExSTED) and demonstrated an increase in resolution of up to 30-fold compared to conventional microscopy (<10 nm lateral and ∼50 nm isotropic). While the increase in resolution is straightforward, we found that high-fidelity labeling via multi-epitopes is required to obtain emitter densities that allow ultrastructural details with ExSTED to be resolved. Our work provides a robust template for super-resolution microscopy of entire cells in the ten nanometer range.
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Affiliation(s)
- Mengfei Gao
- Institut für Biochemie , Freie Universität Berlin , Thielallee 63 , 14195 Berlin , Germany
| | - Riccardo Maraspini
- Max Planck Institute of Molecular Cell Biology and Genetics , Pfotenhauerstraße 108 , 01307 Dresden , Germany
| | - Oliver Beutel
- Max Planck Institute of Molecular Cell Biology and Genetics , Pfotenhauerstraße 108 , 01307 Dresden , Germany
| | - Amin Zehtabian
- Institut für Biochemie , Freie Universität Berlin , Thielallee 63 , 14195 Berlin , Germany
| | - Britta Eickholt
- Institut für Biochemie , Charité Universitätsmedizin Berlin , 10117 Berlin , Germany
| | - Alf Honigmann
- Max Planck Institute of Molecular Cell Biology and Genetics , Pfotenhauerstraße 108 , 01307 Dresden , Germany
| | - Helge Ewers
- Institut für Biochemie , Freie Universität Berlin , Thielallee 63 , 14195 Berlin , Germany
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104
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Wiegering A, Dildrop R, Kalfhues L, Spychala A, Kuschel S, Lier JM, Zobel T, Dahmen S, Leu T, Struchtrup A, Legendre F, Vesque C, Schneider-Maunoury S, Saunier S, Rüther U, Gerhardt C. Cell type-specific regulation of ciliary transition zone assembly in vertebrates. EMBO J 2018; 37:embj.201797791. [PMID: 29650680 PMCID: PMC5978567 DOI: 10.15252/embj.201797791] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 03/12/2018] [Accepted: 03/15/2018] [Indexed: 01/07/2023] Open
Abstract
Ciliopathies are life-threatening human diseases caused by defective cilia. They can often be traced back to mutations of genes encoding transition zone (TZ) proteins demonstrating that the understanding of TZ organisation is of paramount importance. The TZ consists of multimeric protein modules that are subject to a stringent assembly hierarchy. Previous reports place Rpgrip1l at the top of the TZ assembly hierarchy in Caenorhabditis elegans By performing quantitative immunofluorescence studies in RPGRIP1L-/- mouse embryos and human embryonic cells, we recognise a different situation in vertebrates in which Rpgrip1l deficiency affects TZ assembly in a cell type-specific manner. In cell types in which the loss of Rpgrip1l alone does not affect all modules, additional truncation or removal of vertebrate-specific Rpgrip1 results in an impairment of all modules. Consequently, Rpgrip1l and Rpgrip1 synergistically ensure the TZ composition in several vertebrate cell types, revealing a higher complexity of TZ assembly in vertebrates than in invertebrates.
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Affiliation(s)
- Antonia Wiegering
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Renate Dildrop
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Lisa Kalfhues
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - André Spychala
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Stefanie Kuschel
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Johanna Maria Lier
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Thomas Zobel
- Center for Advanced Imaging (CAi), Heinrich Heine University, Düsseldorf, Germany
| | - Stefanie Dahmen
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Tristan Leu
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Andreas Struchtrup
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Flora Legendre
- INSERM, U983, Hôpital Necker-Enfants Malades, Paris, France.,Sorbonne Paris Cité, Faculté de Médecine, Université Paris-Descartes, Paris, France
| | - Christine Vesque
- Paris-Seine (IBPS) - Developmental Biology Laboratory, Institut de Biologie, CNRS, UMR7622, INSERM U1156, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France
| | - Sylvie Schneider-Maunoury
- Paris-Seine (IBPS) - Developmental Biology Laboratory, Institut de Biologie, CNRS, UMR7622, INSERM U1156, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France
| | - Sophie Saunier
- INSERM, U983, Hôpital Necker-Enfants Malades, Paris, France.,Sorbonne Paris Cité, Faculté de Médecine, Université Paris-Descartes, Paris, France
| | - Ulrich Rüther
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
| | - Christoph Gerhardt
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, Düsseldorf, Germany
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105
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Sieben C, Douglass KM, Guichard P, Manley S. Super-resolution microscopy to decipher multi-molecular assemblies. Curr Opin Struct Biol 2018; 49:169-176. [DOI: 10.1016/j.sbi.2018.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 12/12/2022]
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106
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Schnitzbauer J, Wang Y, Zhao S, Bakalar M, Nuwal T, Chen B, Huang B. Correlation analysis framework for localization-based superresolution microscopy. Proc Natl Acad Sci U S A 2018; 115:3219-3224. [PMID: 29531072 PMCID: PMC5879654 DOI: 10.1073/pnas.1711314115] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Superresolution images reconstructed from single-molecule localizations can reveal cellular structures close to the macromolecular scale and are now being used routinely in many biomedical research applications. However, because of their coordinate-based representation, a widely applicable and unified analysis platform that can extract a quantitative description and biophysical parameters from these images is yet to be established. Here, we propose a conceptual framework for correlation analysis of coordinate-based superresolution images using distance histograms. We demonstrate the application of this concept in multiple scenarios, including image alignment, tracking of diffusing molecules, as well as for quantification of colocalization, showing its superior performance over existing approaches.
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Affiliation(s)
- Joerg Schnitzbauer
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - Yina Wang
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - Shijie Zhao
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Matthew Bakalar
- UC Berkeley-UCSF Joint Graduate Group in Bioengineering, University of California, Berkeley, CA 94720
| | - Tulip Nuwal
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - Baohui Chen
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143
| | - Bo Huang
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143;
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143
- Chan Zuckerberg Biohub, San Francisco, CA 94158
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107
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Wang C, Li J, Takemaru KI, Jiang X, Xu G, Wang B. Centrosomal protein Dzip1l binds Cby, promotes ciliary bud formation, and acts redundantly with Bromi to regulate ciliogenesis in the mouse. Development 2018; 145:dev.164236. [PMID: 29487109 DOI: 10.1242/dev.164236] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 02/16/2018] [Indexed: 12/14/2022]
Abstract
The primary cilium is a microtubule-based organelle required for Hedgehog (Hh) signaling and consists of a basal body, a ciliary axoneme and a compartment between the first two structures, called the transition zone (TZ). The TZ serves as a gatekeeper to control protein composition in cilia, but less is known about its role in ciliary bud formation. Here, we show that centrosomal protein Dzip1l is required for Hh signaling between Smoothened and Sufu. Dzip1l colocalizes with basal body appendage proteins and Rpgrip1l, a TZ protein. Loss of Dzip1l results in reduced ciliogenesis and dysmorphic cilia in vivo Dzip1l interacts with, and acts upstream of, Cby, an appendage protein, in ciliogenesis. Dzip1l also has overlapping functions with Bromi (Tbc1d32) in ciliogenesis, cilia morphogenesis and neural tube patterning. Loss of Dzip1l arrests ciliogenesis at the stage of ciliary bud formation from the TZ. Consistent with this, Dzip1l mutant cells fail to remove the capping protein Cp110 (Ccp110) from the distal end of mother centrioles and to recruit Rpgrip1l to the TZ. Therefore, Dzip1l promotes ciliary bud formation and is required for the integrity of the TZ.
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Affiliation(s)
- Chengbing Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Jia Li
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Ken-Ichi Takemaru
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Xiaogang Jiang
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and College of Pharmaceutical Sciences, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, Jiangsu 215123, China
| | - Guoqiang Xu
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and College of Pharmaceutical Sciences, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, Jiangsu 215123, China
| | - Baolin Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA .,Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
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108
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Carli JFM, LeDuc CA, Zhang Y, Stratigopoulos G, Leibel RL. The role of Rpgrip1l, a component of the primary cilium, in adipocyte development and function. FASEB J 2018; 32:3946-3956. [PMID: 29466054 DOI: 10.1096/fj.201701216r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Genetic variants within the FTO (α-ketoglutarate-dependent dioxygenase) gene have been strongly associated with a modest increase in adiposity as a result of increased food intake. These risk alleles are associated with decreased expression of both FTO and neighboring RPGRIP1L (retinitis pigmentosa GTPase regulator-interacting protein 1 like). RPGRIP1L encodes a protein that is critical to the function of the primary cilium, which conveys extracellular information to the cell. Rpgrip1l+/- mice exhibit increased adiposity, in part, as a result of hyperphagia. Here, we describe the effects of Rpgrip1l in adipocytes that may contribute to the adiposity phenotype observed in these animals and possibly in humans who segregate for FTO risk alleles. Loss of Rpgrip1l in 3T3-L1 preadipocytes increased the number of cells that are capable of differentiating into mature adipocytes. Knockout of Rpgrip1l in mature adipocytes using Adipoq-Cre did not increase adiposity in mice that were fed chow or a high-fat diet. We also did not observe any effects of Rpgrip1l knockdown in mature 3T3-L1 adipocytes. Thus, to the extent that Rpgrip1l affects cell-autonomous adipose tissue function, it may do so as a result of the effects conveyed in preadipocytes in which the primary cilium is functionally important. We propose that decreased RPGRIP1L expression in preadipocytes in humans who segregate for FTO obesity risk alleles may increase the storage capacity of adipose tissue.-Martin Carli, J. F., LeDuc, C. A., Zhang, Y., Stratigopoulos, G., Leibel, R. L. The role of Rpgrip1l, a component of the primary cilium, in adipocyte development and function.
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Affiliation(s)
- Jayne F Martin Carli
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, New York, USA.,Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Charles A LeDuc
- Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Yiying Zhang
- Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - George Stratigopoulos
- Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
| | - Rudolph L Leibel
- Naomi Berrie Diabetes Center, Columbia University Medical Center, New York, New York, USA.,Department of Pediatrics, Columbia University Medical Center, New York, New York, USA
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109
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Srivastava S, Molinari E, Raman S, Sayer JA. Many Genes-One Disease? Genetics of Nephronophthisis (NPHP) and NPHP-Associated Disorders. Front Pediatr 2017; 5:287. [PMID: 29379777 PMCID: PMC5770800 DOI: 10.3389/fped.2017.00287] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 12/14/2017] [Indexed: 12/13/2022] Open
Abstract
Nephronophthisis (NPHP) is a renal ciliopathy and an autosomal recessive cause of cystic kidney disease, renal fibrosis, and end-stage renal failure, affecting children and young adults. Molecular genetic studies have identified more than 20 genes underlying this disorder, whose protein products are all related to cilia, centrosome, or mitotic spindle function. In around 15% of cases, there are additional features of a ciliopathy syndrome, including retinal defects, liver fibrosis, skeletal abnormalities, and brain developmental disorders. Alongside, gene identification has arisen molecular mechanistic insights into the disease pathogenesis. The genetic causes of NPHP are discussed in terms of how they help us to define treatable disease pathways including the cyclic adenosine monophosphate pathway, the mTOR pathway, Hedgehog signaling pathways, and DNA damage response pathways. While the underlying pathology of the many types of NPHP remains similar, the defined disease mechanisms are diverse, and a personalized medicine approach for therapy in NPHP patients is likely to be required.
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Affiliation(s)
- Shalabh Srivastava
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.,Renal Unit, City Hospitals Sunderland and South Tyneside NHS Foundation Trust, Sunderland, United Kingdom
| | - Elisa Molinari
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Shreya Raman
- Department of Histopathology, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - John A Sayer
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.,Renal Services, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
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110
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Hartill V, Szymanska K, Sharif SM, Wheway G, Johnson CA. Meckel-Gruber Syndrome: An Update on Diagnosis, Clinical Management, and Research Advances. Front Pediatr 2017; 5:244. [PMID: 29209597 PMCID: PMC5701918 DOI: 10.3389/fped.2017.00244] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/02/2017] [Indexed: 11/13/2022] Open
Abstract
Meckel-Gruber syndrome (MKS) is a lethal autosomal recessive congenital anomaly syndrome caused by mutations in genes encoding proteins that are structural or functional components of the primary cilium. Conditions that are caused by mutations in ciliary genes are collectively termed the ciliopathies, and MKS represents the most severe condition in this group of disorders. The primary cilium is a microtubule-based organelle, projecting from the apical surface of vertebrate cells. It acts as an "antenna" that receives and transduces chemosensory and mechanosensory signals, but also regulates diverse signaling pathways, such as Wnt and Shh, that have important roles during embryonic development. Most MKS proteins localize to a distinct ciliary compartment called the transition zone (TZ) that regulates the trafficking of cargo proteins or lipids. In this review, we provide an up-to-date summary of MKS clinical features, molecular genetics, and clinical diagnosis. MKS has a highly variable phenotype, extreme genetic heterogeneity, and displays allelism with other related ciliopathies such as Joubert syndrome, presenting significant challenges to diagnosis. Recent advances in genetic technology, with the widespread use of multi-gene panels for molecular testing, have significantly improved diagnosis, genetic counseling, and the clinical management of MKS families. These include the description of some limited genotype-phenotype correlations. We discuss recent insights into the molecular basis of disease in MKS, since the functions of some of the relevant ciliary proteins have now been determined. A common molecular etiology appears to be disruption of ciliary TZ structure and function, affecting essential developmental signaling and the regulation of secondary messengers.
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Affiliation(s)
- Verity Hartill
- Department of Clinical Genetics, Yorkshire Regional Genetics Service, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, United Kingdom
| | - Katarzyna Szymanska
- Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, United Kingdom
| | - Saghira Malik Sharif
- Department of Clinical Genetics, Yorkshire Regional Genetics Service, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom
| | - Gabrielle Wheway
- Faculty of Health and Applied Sciences, Department of Applied Sciences, UWE Bristol, Bristol, United Kingdom
| | - Colin A Johnson
- Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, United Kingdom
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