1
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Cuevas M, Terhune E, Wethey C, James M, Netsanet R, Grofova D, Monley A, Hadley Miller N. Cytoskeletal Keratins Are Overexpressed in a Zebrafish Model of Idiopathic Scoliosis. Genes (Basel) 2023; 14:genes14051058. [PMID: 37239418 DOI: 10.3390/genes14051058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
Idiopathic scoliosis (IS) is a three-dimensional rotation of the spine >10 degrees with an unknown etiology. Our laboratory established a late-onset IS model in zebrafish (Danio rerio) containing a deletion in kif7. A total of 25% of kif7co63/co63 zebrafish develop spinal curvatures and are otherwise developmentally normal, although the molecular mechanisms underlying the scoliosis are unknown. To define transcripts associated with scoliosis in this model, we performed bulk mRNA sequencing on 6 weeks past fertilization (wpf) kif7co63/co63 zebrafish with and without scoliosis. Additionally, we sequenced kif7co63/co63, kif7co63/+, and AB zebrafish (n = 3 per genotype). Sequencing reads were aligned to the GRCz11 genome and FPKM values were calculated. Differences between groups were calculated for each transcript by the t-test. Principal component analysis showed that transcriptomes clustered by sample age and genotype. kif7 mRNA was mildly reduced in both homozygous and heterozygous zebrafish compared to AB. Sonic hedgehog target genes were upregulated in kif7co63/co63 zebrafish over AB, but no difference was detected between scoliotic and non-scoliotic mutants. The top upregulated genes in scoliotic zebrafish were cytoskeletal keratins. Pankeratin staining of 6 wpf scoliotic and non-scoliotic kif7co63/co63 zebrafish showed increased keratin levels within the zebrafish musculature and intervertebral disc (IVD). Keratins are major components of the embryonic notochord, and aberrant keratin expression has been associated with intervertebral disc degeneration (IVDD) in both zebrafish and humans. The role of increased keratin accumulation as a molecular mechanism associated with the onset of scoliosis warrants further study.
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Affiliation(s)
- Melissa Cuevas
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Elizabeth Terhune
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Cambria Wethey
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - MkpoutoAbasi James
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rahwa Netsanet
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Denisa Grofova
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anna Monley
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Musculoskeletal Research Center, Children's Hospital Colorado, Aurora, CO 80045, USA
| | - Nancy Hadley Miller
- Department of Orthopedics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Musculoskeletal Research Center, Children's Hospital Colorado, Aurora, CO 80045, USA
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2
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Kumar D, Reiter JF. A kinesin mimics DNA. Nat Cell Biol 2022; 24:1015-1016. [PMID: 35798844 DOI: 10.1038/s41556-022-00958-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dhivya Kumar
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA. .,Chan Zuckerberg Biohub, San Francisco, CA, USA.
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3
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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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Abstract
Hedgehog (Hh) proteins constitute one family of a small number of secreted signaling proteins that together regulate multiple aspects of animal development, tissue homeostasis and regeneration. Originally uncovered through genetic analyses in Drosophila, their subsequent discovery in vertebrates has provided a paradigm for the role of morphogens in positional specification. Most strikingly, the Sonic hedgehog protein was shown to mediate the activity of two classic embryonic organizing centers in vertebrates and subsequent studies have implicated it and its paralogs in a myriad of processes. Moreover, dysfunction of the signaling pathway has been shown to underlie numerous human congenital abnormalities and diseases, especially certain types of cancer. This review focusses on the genetic studies that uncovered the key components of the Hh signaling system and the subsequent, biochemical, cell and structural biology analyses of their functions. These studies have revealed several novel processes and principles, shedding new light on the cellular and molecular mechanisms underlying cell-cell communication. Notable amongst these are the involvement of cholesterol both in modifying the Hh proteins and in activating its transduction pathway, the role of cytonemes, filipodia-like extensions, in conveying Hh signals between cells; and the central importance of the Primary Cilium as a cellular compartment within which the components of the signaling pathway are sequestered and interact.
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Affiliation(s)
- Philip William Ingham
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
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5
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Zhang Y, Lu K, Wu X, Liu H, Xin J, Wang X, Gong W, Zhao Q, Wang M, Chu H, Du M, Tao G, Zhang Z. Genetic variants in the Hedgehog signaling pathway genes are associated with gastric cancer risk in a Chinese Han population. J Biomed Res 2022; 36:22-31. [PMID: 35403607 PMCID: PMC8894289 DOI: 10.7555/jbr.35.20210091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Yujuan Zhang
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Kai Lu
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Xu Wu
- Department of General Surgery, the Affiliated Huai'an No.1 People's Hospital of Nanjing Medical University, Huai'an, Jiangsu 223300, China
| | - Hanting Liu
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Junyi Xin
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Xiaowei Wang
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Weida Gong
- Department of General Surgery, Yixing People's Hospital, Yixing, Jiangsu 214200, China
| | - Qinghong Zhao
- Department of General Surgery, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210011, China
| | - Meilin Wang
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Environmental Genomics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Haiyan Chu
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
| | - Mulong Du
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing 211166, China
- Mulong Du, Department of Biostatistics, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Jiangning District, Nanjing, Jiangsu 211166, China. Tel: +86-25-86868423, E-mail:
| | - Guoquan Tao
- Department of General Surgery, the Affiliated Huai'an No.1 People's Hospital of Nanjing Medical University, Huai'an, Jiangsu 223300, China
- Guoquan Tao, Department of General Surgery, the Affiliated Huai'an No.1 People's Hospital of Nanjing Medical University, No. 1 Huanghe Western Road, Huaiyin District, Huai'an, Jiangsu 223300, China. Tel: +86-517-84922412, E-mail:
| | - Zhengdong Zhang
- Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Genetic Toxicology, the Key Laboratory of Modern Toxicology of Ministry of Education, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Department of Environmental Genomics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 211166, China
- Zhengdong Zhang, School of Public Health, Nanjing Medical University, 101 Longmian Avenue, Jiangning District, Nanjing, Jiangsu 211166, China. Tel/Fax: +86-25-86868423/+86-25-86868499, E-mail:
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6
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Gigante ED, Caspary T. Signaling in the primary cilium through the lens of the Hedgehog pathway. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2020; 9:e377. [PMID: 32084300 DOI: 10.1002/wdev.377] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/22/2020] [Accepted: 01/25/2020] [Indexed: 12/14/2022]
Abstract
Cilia are microtubule-based, cell-surface projections whose machinery is evolutionarily conserved. In vertebrates, cilia are observed on almost every cell type and are either motile or immotile. Immotile sensory, or primary cilia, are responsive to extracellular ligands and signals. Cilia can be thought of as compartments, functionally distinct from the cell that provides an environment for signaling cascades. Hedgehog is a critical developmental signaling pathway which is functionally linked to primary cilia in vertebrates. The major components of the vertebrate Hedgehog signaling pathway dynamically localize to the ciliary compartment and ciliary membrane. Critically, G-protein coupled receptor (GPCR) Smoothened, the obligate transducer of the pathway, is enriched and activated in the cilium. While Smoothened is the most intensely studied ciliary receptor, many GPCRs localize within cilia. Understanding the link between Smoothened and cilia defines common features, and distinctions, of GPCR signaling within the primary cilium. This article is categorized under: Signaling Pathways > Global Signaling Mechanisms Signaling Pathways > Cell Fate Signaling.
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Affiliation(s)
- Eduardo D Gigante
- Graduate Program in Neuroscience, Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
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7
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Lau CI, Barbarulo A, Solanki A, Saldaña JI, Crompton T. The kinesin motor protein Kif7 is required for T-cell development and normal MHC expression on thymic epithelial cells (TEC) in the thymus. Oncotarget 2018; 8:24163-24176. [PMID: 28445929 PMCID: PMC5421836 DOI: 10.18632/oncotarget.15241] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 01/21/2017] [Indexed: 11/30/2022] Open
Abstract
Kif7 is a ciliary kinesin motor protein that regulates mammalian Hedgehog pathway activation through influencing structure of the primary cilium. Here we show that Kif7 is required for normal T-cell development, despite the fact that T-cells lack primary cilia. Analysis of Kif7-deficient thymus showed that Kif7-deficiency increases the early CD44+CD25+CD4-CD8- thymocyte progenitor population but reduces differentiation to CD4+CD8+ double positive (DP) cell. At the transition from DP to mature T-cell, Kif7-deficiency selectively delayed maturation to the CD8 lineage. Expression of CD5, which correlates with TCR signal strength, was reduced on DP and mature CD4 and CD8 cells, as a result of thymocyte-intrinsic Kif7-deficiency, and Kif7-deficient T-cells from radiation chimeras activated less efficiently when stimulated with anti-CD3 and anti-CD28 in vitro. Kif7-deficient thymocytes showed higher expression of the Hedgehog target gene Ptch1 than WT, but were less sensitive to treatment with recombinant Shh, and Kif7-deficient T-cell development was refractory to neutralisation of endogenous Hh proteins, indicating that Kif7-deficient thymocytes were unable to interpret changes in the Hedgehog signal. In addition, Kif7-deficiency reduced cell-surface MHCII expression on thymic epithelial cells.
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Affiliation(s)
- Ching-In Lau
- Immunobiology Section, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Alessandro Barbarulo
- Immunobiology Section, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Anisha Solanki
- Immunobiology Section, UCL Great Ormond Street Institute of Child Health, London, UK
| | - José Ignacio Saldaña
- Immunobiology Section, UCL Great Ormond Street Institute of Child Health, London, UK.,School of Health, Sport and Bioscience, University of East London, London, UK
| | - Tessa Crompton
- Immunobiology Section, UCL Great Ormond Street Institute of Child Health, London, UK
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8
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Pak E, Segal RA. Hedgehog Signal Transduction: Key Players, Oncogenic Drivers, and Cancer Therapy. Dev Cell 2017; 38:333-44. [PMID: 27554855 DOI: 10.1016/j.devcel.2016.07.026] [Citation(s) in RCA: 227] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Hedgehog (Hh) signaling pathway governs complex developmental processes, including proliferation and patterning within diverse tissues. These activities rely on a tightly regulated transduction system that converts graded Hh input signals into specific levels of pathway activity. Uncontrolled activation of Hh signaling drives tumor initiation and maintenance. However, recent entry of pathway-specific inhibitors into the clinic reveals mixed patient responses and thus prompts further exploration of pathway activation and inhibition. In this review, we share emerging insights into regulated and oncogenic Hh signaling, supplemented with updates on the development and use of Hh pathway-targeted therapies.
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Affiliation(s)
- Ekaterina Pak
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Rosalind A Segal
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA.
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9
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Wu F, Zhang Y, Sun B, McMahon AP, Wang Y. Hedgehog Signaling: From Basic Biology to Cancer Therapy. Cell Chem Biol 2017; 24:252-280. [PMID: 28286127 DOI: 10.1016/j.chembiol.2017.02.010] [Citation(s) in RCA: 218] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/29/2016] [Accepted: 02/10/2017] [Indexed: 02/07/2023]
Abstract
The Hedgehog (HH) signaling pathway was discovered originally as a key pathway in embryonic patterning and development. Since its discovery, it has become increasingly clear that the HH pathway also plays important roles in a multitude of cancers. Therefore, HH signaling has emerged as a therapeutic target of interest for cancer therapy. In this review, we provide a brief overview of HH signaling and the key molecular players involved and offer an up-to-date summary of our current knowledge of endogenous and exogenous small molecules that modulate HH signaling. We discuss experiences and lessons learned from the decades-long efforts toward the development of cancer therapies targeting the HH pathway. Challenges to develop next-generation cancer therapies are highlighted.
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Affiliation(s)
- Fujia Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Bo Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Andrew P McMahon
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad-CIRM Center for Regenerative Medicine and Stem Cell Research, W.M. Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Yu Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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10
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He M, Agbu S, Anderson KV. Microtubule Motors Drive Hedgehog Signaling in Primary Cilia. Trends Cell Biol 2017; 27:110-125. [PMID: 27765513 PMCID: PMC5258846 DOI: 10.1016/j.tcb.2016.09.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/08/2016] [Accepted: 09/23/2016] [Indexed: 01/05/2023]
Abstract
The mammalian Hedgehog (Hh) signaling pathway is required for development and for maintenance of adult stem cells, and overactivation of the pathway can cause tumorigenesis. All responses to Hh family ligands in mammals require the primary cilium, an ancient microtubule-based organelle that extends from the cell surface. Genetic studies in mice and humans have defined specific functions for cilium-associated microtubule motor proteins: they act in the construction and disassembly of the primary cilium, they control ciliary length and stability, and some have direct roles in mammalian Hh signal transduction. These studies highlight how integrated genetic and cell biological studies can define the molecular mechanisms that underlie cilium-associated health and disease.
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Affiliation(s)
- Mu He
- Department of Physiology and Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Stephanie Agbu
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA; Biochemistry, Cell, and Molecular Biology Program, Weill Graduate School of Medical Sciences of Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
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Jin Z, Schwend T, Fu J, Bao Z, Liang J, Zhao H, Mei W, Yang J. Members of the Rusc protein family interact with Sufu and inhibit vertebrate Hedgehog signaling. Development 2016; 143:3944-3955. [PMID: 27633991 DOI: 10.1242/dev.138917] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 09/01/2016] [Indexed: 12/20/2022]
Abstract
Hedgehog (Hh) signaling is fundamentally important for development and adult tissue homeostasis. It is well established that in vertebrates Sufu directly binds and inhibits Gli proteins, the downstream mediators of Hh signaling. However, it is unclear how the inhibitory function of Sufu towards Gli is regulated. Here we report that the Rusc family of proteins, the biological functions of which are poorly understood, form a heterotrimeric complex with Sufu and Gli. Upon Hh signaling, Rusc is displaced from this complex, followed by dissociation of Gli from Sufu. In mammalian fibroblast cells, knockdown of Rusc2 potentiates Hh signaling by accelerating signaling-induced dissociation of the Sufu-Gli protein complexes. In Xenopus embryos, knockdown of Rusc1 or overexpression of a dominant-negative Rusc enhances Hh signaling during eye development, leading to severe eye defects. Our study thus uncovers a novel regulatory mechanism controlling the response of cells to Hh signaling in vertebrates.
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Affiliation(s)
- Zhigang Jin
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL 61802, USA
| | - Tyler Schwend
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL 61802, USA
| | - Jia Fu
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL 61802, USA
| | - Zehua Bao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Jing Liang
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Wenyan Mei
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL 61802, USA
| | - Jing Yang
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL 61802, USA
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12
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Marshall RA, Osborn DPS. Zebrafish: a vertebrate tool for studying basal body biogenesis, structure, and function. Cilia 2016; 5:16. [PMID: 27168933 PMCID: PMC4862167 DOI: 10.1186/s13630-016-0036-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 03/01/2016] [Indexed: 02/27/2023] Open
Abstract
Understanding the role of basal bodies (BBs) during development and disease has been largely overshadowed by research into the function of the cilium. Although these two organelles are closely associated, they have specific roles to complete for successful cellular development. Appropriate development and function of the BB are fundamental for cilia function. Indeed, there are a growing number of human genetic diseases affecting ciliary development, known collectively as the ciliopathies. Accumulating evidence suggests that BBs establish cell polarity, direct ciliogenesis, and provide docking sites for proteins required within the ciliary axoneme. Major contributions to our knowledge of BB structure and function have been provided by studies in flagellated or ciliated unicellular eukaryotic organisms, specifically Tetrahymena and Chlamydomonas. Reproducing these and other findings in vertebrates has required animal in vivo models. Zebrafish have fast become one of the primary organisms of choice for modeling vertebrate functional genetics. Rapid ex-utero development, proficient egg laying, ease of genetic manipulation, and affordability make zebrafish an attractive vertebrate research tool. Furthermore, zebrafish share over 80 % of disease causing genes with humans. In this article, we discuss the merits of using zebrafish to study BB functional genetics, review current knowledge of zebrafish BB ultrastructure and mechanisms of function, and consider the outlook for future zebrafish-based BB studies.
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Affiliation(s)
- Ryan A Marshall
- Cell Sciences and Genetics Research Centre, St George's University of London, London, SW17 0RE UK
| | - Daniel P S Osborn
- Cell Sciences and Genetics Research Centre, St George's University of London, London, SW17 0RE UK
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13
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Gorojankina T. Hedgehog signaling pathway: a novel model and molecular mechanisms of signal transduction. Cell Mol Life Sci 2016; 73:1317-32. [PMID: 26762301 PMCID: PMC11108571 DOI: 10.1007/s00018-015-2127-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 12/21/2022]
Abstract
The Hedgehog (Hh) signaling pathway has numerous roles in the control of cell proliferation, tissue patterning and stem cell maintenance. In spite of intensive study, the mechanisms of Hh signal transduction are not completely understood. Here I review published data and present a novel model of vertebrate Hh signaling suggesting that Smoothened (Smo) functions as a G-protein-coupled receptor in cilia. This is the first model to propose molecular mechanisms for the major steps of Hh signaling, including inhibition of Smo by Patched, Smo activation, and signal transduction from active Smo to Gli transcription factors. It also suggests a novel role for the negative pathway regulators Sufu and PKA in these processes.
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Affiliation(s)
- Tatiana Gorojankina
- Neuroscience Paris-Saclay Institute (Neuro-PSI), UMR 9197, CNRS, Université Paris-Sud, Bât. 32/33, CNRS, 91190, Gif-sur-Yvette, France.
- Institut Curie, Centre de Recherche, Orsay, France.
- CNRS UMR3347, 91400, Orsay, France.
- Univ. Paris Sud, Université Paris Saclay, Orsay, France.
- INSERM U1021, 91400, Orsay, France.
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14
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Chassaing N, Davis EE, McKnight KL, Niederriter AR, Causse A, David V, Desmaison A, Lamarre S, Vincent-Delorme C, Pasquier L, Coubes C, Lacombe D, Rossi M, Dufier JL, Dollfus H, Kaplan J, Katsanis N, Etchevers HC, Faguer S, Calvas P. Targeted resequencing identifies PTCH1 as a major contributor to ocular developmental anomalies and extends the SOX2 regulatory network. Genome Res 2016; 26:474-85. [PMID: 26893459 PMCID: PMC4817771 DOI: 10.1101/gr.196048.115] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 02/04/2016] [Indexed: 12/17/2022]
Abstract
Ocular developmental anomalies (ODA) such as anophthalmia/microphthalmia (AM) or anterior segment dysgenesis (ASD) have an estimated combined prevalence of 3.7 in 10,000 births. Mutations in SOX2 are the most frequent contributors to severe ODA, yet account for a minority of the genetic drivers. To identify novel ODA loci, we conducted targeted high-throughput sequencing of 407 candidate genes in an initial cohort of 22 sporadic ODA patients. Patched 1 (PTCH1), an inhibitor of sonic hedgehog (SHH) signaling, harbored an enrichment of rare heterozygous variants in comparison to either controls, or to the other candidate genes (four missense and one frameshift); targeted resequencing of PTCH1 in a second cohort of 48 ODA patients identified two additional rare nonsynonymous changes. Using multiple transient models and a CRISPR/Cas9-generated mutant, we show physiologically relevant phenotypes altering SHH signaling and eye development upon abrogation of ptch1 in zebrafish for which in vivo complementation assays using these models showed that all six patient missense mutations affect SHH signaling. Finally, through transcriptomic and ChIP analyses, we show that SOX2 binds to an intronic domain of the PTCH1 locus to regulate PTCH1 expression, findings that were validated both in vitro and in vivo. Together, these results demonstrate that PTCH1 mutations contribute to as much as 10% of ODA, identify the SHH signaling pathway as a novel effector of SOX2 activity during human ocular development, and indicate that ODA is likely the result of overactive SHH signaling in humans harboring mutations in either PTCH1 or SOX2.
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Affiliation(s)
- Nicolas Chassaing
- CHU Toulouse, Service de Génétique Médicale, Hôpital Purpan, 31059 Toulouse, France; Université Paul-Sabatier Toulouse III, EA-4555, 31000 Toulouse, France; Inserm U1056, 31000 Toulouse, France
| | - Erica E Davis
- Center for Human Disease Modeling, Duke University Medical Center, Durham, North Carolina 27701, USA; Department of Pediatrics and Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27701, USA
| | - Kelly L McKnight
- Center for Human Disease Modeling, Duke University Medical Center, Durham, North Carolina 27701, USA
| | - Adrienne R Niederriter
- Center for Human Disease Modeling, Duke University Medical Center, Durham, North Carolina 27701, USA
| | - Alexandre Causse
- Université Paul-Sabatier Toulouse III, EA-4555, 31000 Toulouse, France; CHU Toulouse, Service d'Ophtalmologie, Hôpital Purpan, 31059 Toulouse, France
| | - Véronique David
- Institut de Génétique et Développement, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, Faculté de Médecine, 35043 Rennes, France; Laboratoire de Génétique Moléculaire, CHU Pontchaillou, 35043 Rennes Cedex, France
| | - Annaïck Desmaison
- Université Paul-Sabatier Toulouse III, EA-4555, 31000 Toulouse, France
| | - Sophie Lamarre
- Université de Toulouse; INSA, UPS, INP, LISBP, F-31077 Toulouse, France; INRA, UMR792, Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France; Plateforme Biopuces de la Génopole de Toulouse Midi Pyrénées, INSA/DGBA 135, 31077 Toulouse, France
| | | | - Laurent Pasquier
- Service de Génétique Clinique, Hôpital Sud, 35200 Rennes, France
| | - Christine Coubes
- Service de Génétique Médicale, Hôpital Arnaud de Villeneuve, 34295 Montpellier, France
| | - Didier Lacombe
- Service de Génétique Médicale, Hôpital Pellegrin, 33076 Bordeaux Cedex, France; Université Bordeaux Segalen, Laboratoire MRGM, 33076 Bordeaux, France
| | - Massimiliano Rossi
- Service de Génétique, Hospices Civils de Lyon, Groupement Hospitalier Est, 69677 Bron, France; INSERM U1028 UMR CNRS 5292, UCBL, CRNL TIGER Team, 69677 Bron Cedex, France
| | - Jean-Louis Dufier
- Service d'Ophtalmologie, Hôpital Necker Enfants Malades, 75015 Paris, France
| | - Helene Dollfus
- Service de Génétique Médicale, Hôpitaux Universitaires de Strasbourg, 67091 Strasbourg, France
| | - Josseline Kaplan
- INSERM U781 & Department of Genetics, Paris Descartes University, 75015 Paris, France
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University Medical Center, Durham, North Carolina 27701, USA; Department of Pediatrics and Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27701, USA
| | - Heather C Etchevers
- Université Paul-Sabatier Toulouse III, EA-4555, 31000 Toulouse, France; INSERM, UMR_S910, Aix-Marseille University, Faculté de Médecine, 13385 Marseille, France
| | | | - Patrick Calvas
- CHU Toulouse, Service de Génétique Médicale, Hôpital Purpan, 31059 Toulouse, France; Université Paul-Sabatier Toulouse III, EA-4555, 31000 Toulouse, France; Inserm U1056, 31000 Toulouse, France
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15
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Liu C, Song G, Mao L, Long Y, Li Q, Cui Z. Generation of an Enhancer-Trapping Vector for Insertional Mutagenesis in Zebrafish. PLoS One 2015; 10:e0139612. [PMID: 26436547 PMCID: PMC4593583 DOI: 10.1371/journal.pone.0139612] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 09/14/2015] [Indexed: 01/01/2023] Open
Abstract
Enhancer trapping (ET) is a powerful approach to establish tissue- or cell-specific reporters and identify expression patterns of uncharacterized genes. Although a number of enhancer-trapping vectors have been developed and a large library of fish lines with distinct tissue- or cell-specific expression of reporter genes have been generated, the specificity and efficiency of trapping vectors need to be improved because of the bias interaction of minimal promoters with genomic enhancers. Accordingly, we generated an enhancer-trapping vector pTME that contains a minimal mouse metallothionein gene (mMTI) promoter upstream of EGFP reporter. In the first round of screening, twelve zebrafish lines that carry a single copy of ET cassettes were characterized to have tissue- or cell-specific EGFP expression. One of the highly conserved noncoding elements near an insertion site of trapping cassettes was characterized as an enhancer that can specifically regulate the expression of EGFP in cells of the central nervous system. In addition, the pTME vector contains a mutation-cassette that is able to effectively block the transcription of an endogenous gene in an ET line with ubiquitous EGFP expression. Thus, the pTME vector can be used as an alternative tool for both enhancer trapping and mutagenesis across a target genome.
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Affiliation(s)
- Chunyan Liu
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guili Song
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
| | - Lin Mao
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong Long
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
| | - Qing Li
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
- * E-mail: (ZC); (QL)
| | - Zongbin Cui
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China
- * E-mail: (ZC); (QL)
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16
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Deubiquitination of Ci/Gli by Usp7/HAUSP Regulates Hedgehog Signaling. Dev Cell 2015; 34:58-72. [PMID: 26120032 DOI: 10.1016/j.devcel.2015.05.016] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 03/18/2015] [Accepted: 05/19/2015] [Indexed: 01/20/2023]
Abstract
Hedgehog (Hh) signaling plays essential roles in animal development and tissue homeostasis, and its misregulation causes congenital diseases and cancers. Regulation of the ubiquitin/proteasome-mediated proteolysis of Ci/Gli transcription factors is central to Hh signaling, but whether deubiquitinase is involved in this process remains unknown. Here, we show that Hh stimulates the binding of a ubiquitin-specific protease Usp7 to Ci, which positively regulates Hh signaling activity through inhibiting Ci ubiquitination and degradation mediated by both Slimb-Cul1 and Hib-Cul3 E3 ligases. Furthermore, we find that Usp7 forms a complex with GMP-synthetase (GMPS) to promote Hh pathway activity. Finally, we show that the mammalian counterpart of Usp7, HAUSP, positively regulates Hh signaling by modulating Gli ubiquitination and stability. Our findings reveal a conserved mechanism by which Ci/Gli is stabilized by a deubiquitination enzyme and identify Usp7/HUASP as a critical regulator of Hh signaling and potential therapeutic target for Hh-related cancers.
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17
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Pusapati GV, Rohatgi R. Location, location, and location: compartmentalization of Hedgehog signaling at primary cilia. EMBO J 2014; 33:1852-4. [PMID: 25037564 DOI: 10.15252/embj.201489294] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Ganesh V Pusapati
- Departments of Medicine and Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - Rajat Rohatgi
- Departments of Medicine and Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
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18
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He M, Subramanian R, Bangs F, Omelchenko T, Liem KF, Kapoor TM, Anderson KV. The kinesin-4 protein Kif7 regulates mammalian Hedgehog signalling by organizing the cilium tip compartment. Nat Cell Biol 2014; 16:663-72. [PMID: 24952464 PMCID: PMC4085576 DOI: 10.1038/ncb2988] [Citation(s) in RCA: 214] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 05/13/2014] [Indexed: 12/12/2022]
Abstract
Mammalian Hedgehog (Hh) signal transduction requires a primary cilium, a microtubule-based organelle, and the Gli-Sufu complexes that mediate Hh signalling, which are enriched at cilia tips. Kif7, a kinesin-4 family protein, is a conserved regulator of the Hh signalling pathway and a human ciliopathy protein. Here we show that Kif7 localizes to the cilium tip, the site of microtubule plus ends, where it limits cilium length and controls cilium structure. Purified recombinant Kif7 binds the plus ends of growing microtubules in vitro, where it reduces the rate of microtubule growth and increases the frequency of microtubule catastrophe. Kif7 is not required for normal intraflagellar transport or for trafficking of Hh pathway proteins into cilia. Instead, a central function of Kif7 in the mammalian Hh pathway is to control cilium architecture and to create a single cilium tip compartment, where Gli-Sufu activity can be correctly regulated.
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Affiliation(s)
- Mu He
- 1] Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue New York, New York 10065, USA [2] Program in Biochemistry and Structural Biology, Cell and Developmental Biology, and Molecular Biology, Weill Cornell Graduate School of Medical Sciences, Cornell University, 1300 York Avenue New York, New York 10065, USA
| | - Radhika Subramanian
- Laboratory of Chemistry and Cell Biology, The Rockefeller University, 1230 York Avenue New York, New York 10065, USA
| | - Fiona Bangs
- Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue New York, New York 10065, USA
| | - Tatiana Omelchenko
- Cell Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue New York, New York 10065, USA
| | - Karel F Liem
- 1] Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue New York, New York 10065, USA [2]
| | - Tarun M Kapoor
- Laboratory of Chemistry and Cell Biology, The Rockefeller University, 1230 York Avenue New York, New York 10065, USA
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue New York, New York 10065, USA
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19
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G-protein-coupled receptors, Hedgehog signaling and primary cilia. Semin Cell Dev Biol 2014; 33:63-72. [PMID: 24845016 DOI: 10.1016/j.semcdb.2014.05.002] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 05/12/2014] [Indexed: 12/21/2022]
Abstract
The Hedgehog (Hh) pathway has become an important model to study the cell biology of primary cilia, and reciprocally, the study of ciliary processes provides an opportunity to solve longstanding mysteries in the mechanism of vertebrate Hh signal transduction. The cilium is emerging as an unique compartment for G-protein-coupled receptor (GPCR) signaling in many systems. Two members of the GPCR family, Smoothened and Gpr161, play important roles in the Hh pathway. We review the current understanding of how these proteins may function to regulate Hh signaling and also highlight some of the critical unanswered questions being tackled by the field. Uncovering GPCR-regulated mechanisms important in Hh signaling may provide therapeutic strategies against the Hh pathway that plays important roles in development, regeneration and cancer.
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20
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Zhang Z, Feng J, Pan C, Lv X, Wu W, Zhou Z, Liu F, Zhang L, Zhao Y. Atrophin-Rpd3 complex represses Hedgehog signaling by acting as a corepressor of CiR. ACTA ACUST UNITED AC 2014; 203:575-83. [PMID: 24385484 PMCID: PMC3840934 DOI: 10.1083/jcb.201306012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The evolutionarily conserved Hedgehog (Hh) signaling pathway is transduced by the Cubitus interruptus (Ci)/Gli family of transcription factors that exist in two distinct repressor (Ci(R)/Gli(R)) and activator (Ci(A)/Gli(A)) forms. Aberrant activation of Hh signaling is associated with various human cancers, but the mechanism through which Ci(R)/Gli(R) properly represses target gene expression is poorly understood. Here, we used Drosophila melanogaster and zebrafish models to define a repressor function of Atrophin (Atro) in Hh signaling. Atro directly bound to Ci through its C terminus. The N terminus of Atro interacted with a histone deacetylase, Rpd3, to recruit it to a Ci-binding site at the decapentaplegic (dpp) locus and reduce dpp transcription through histone acetylation regulation. The repressor function of Atro in Hh signaling was dependent on Ci. Furthermore, Rerea, a homologue of Atro in zebrafish, repressed the expression of Hh-responsive genes. We propose that the Atro-Rpd3 complex plays a conserved role to function as a Ci(R) corepressor.
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Affiliation(s)
- Zhao Zhang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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21
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Maurya AK, Ben J, Zhao Z, Lee RTH, Niah W, Ng ASM, Iyu A, Yu W, Elworthy S, van Eeden FJM, Ingham PW. Positive and negative regulation of Gli activity by Kif7 in the zebrafish embryo. PLoS Genet 2013; 9:e1003955. [PMID: 24339784 PMCID: PMC3854788 DOI: 10.1371/journal.pgen.1003955] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 09/30/2013] [Indexed: 12/21/2022] Open
Abstract
Loss of function mutations of Kif7, the vertebrate orthologue of the Drosophila Hh pathway component Costal2, cause defects in the limbs and neural tubes of mice, attributable to ectopic expression of Hh target genes. While this implies a functional conservation of Cos2 and Kif7 between flies and vertebrates, the association of Kif7 with the primary cilium, an organelle absent from most Drosophila cells, suggests their mechanisms of action may have diverged. Here, using mutant alleles induced by Zinc Finger Nuclease-mediated targeted mutagenesis, we show that in zebrafish, Kif7 acts principally to suppress the activity of the Gli1 transcription factor. Notably, we find that endogenous Kif7 protein accumulates not only in the primary cilium, as previously observed in mammalian cells, but also in cytoplasmic puncta that disperse in response to Hh pathway activation. Moreover, we show that Drosophila Costal2 can substitute for Kif7, suggesting a conserved mode of action of the two proteins. We show that Kif7 interacts with both Gli1 and Gli2a and suggest that it functions to sequester Gli proteins in the cytoplasm, in a manner analogous to the regulation of Ci by Cos2 in Drosophila. We also show that zebrafish Kif7 potentiates Gli2a activity by promoting its dissociation from the Suppressor of Fused (Sufu) protein and present evidence that it mediates a Smo dependent modification of the full length form of Gli2a. Surprisingly, the function of Kif7 in the zebrafish embryo appears restricted principally to mesodermal derivatives, its inactivation having little effect on neural tube patterning, even when Sufu protein levels are depleted. Remarkably, zebrafish lacking all Kif7 function are viable, in contrast to the peri-natal lethality of mouse kif7 mutants but similar to some Acrocallosal or Joubert syndrome patients who are homozygous for loss of function KIF7 alleles.
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Affiliation(s)
- Ashish Kumar Maurya
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Jin Ben
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
| | - Zhonghua Zhao
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
| | | | - Weixin Niah
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
| | | | - Audrey Iyu
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
| | - Weimiao Yu
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
| | - Stone Elworthy
- MRC Centre for Developmental and Biomedical Genetics, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Fredericus J. M. van Eeden
- MRC Centre for Developmental and Biomedical Genetics, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Philip William Ingham
- A*STAR Institute of Molecular & Cell Biology, Proteos, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
- MRC Centre for Developmental and Biomedical Genetics, University of Sheffield, Western Bank, Sheffield, United Kingdom
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22
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Oh SA, Allen T, Kim GJ, Sidorova A, Borg M, Park SK, Twell D. Arabidopsis Fused kinase and the Kinesin-12 subfamily constitute a signalling module required for phragmoplast expansion. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:308-19. [PMID: 22709276 DOI: 10.1111/j.1365-313x.2012.05077.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The conserved Fused kinase plays vital but divergent roles in many organisms from Hedgehog signalling in Drosophila to polarization and chemotaxis in Dictyostelium. Previously we have shown that Arabidopsis Fused kinase termed TWO-IN-ONE (TIO) is essential for cytokinesis in both sporophytic and gametophytic cell types. Here using in vivo imaging of GFP-tagged microtubules in dividing microspores we show that TIO is required for expansion of the phragmoplast. We identify the phragmoplast-associated kinesins, PAKRP1/Kinesin-12A and PAKRP1L/Kinesin-12B, as TIO-interacting proteins and determine TIO-Kinesin-12 interaction domains and their requirement in male gametophytic cytokinesis. Our results support the role of TIO as a functional protein kinase that interacts with Kinesin-12 subfamily members mainly through the C-terminal ARM repeat domain, but with a contribution from the N-terminal kinase domain. The interaction of TIO with Kinesin proteins and the functional requirement of their interaction domains support the operation of a Fused kinase signalling module in phragmoplast expansion that depends upon conserved structural features in diverse Fused kinases.
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Affiliation(s)
- Sung Aeong Oh
- Department of Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
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23
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Sasai N, Briscoe J. Primary cilia and graded Sonic Hedgehog signaling. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2012; 1:753-72. [PMID: 23799571 DOI: 10.1002/wdev.43] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cilia are evolutionary-conserved microtubule-containing organelles protruding from the surface of cells. They are classified into two types--primary and motile cilia. Primary cilia are nearly ubiquitous, at least in vertebrate cells, and it has become apparent that they play an essential role in the intracellular transduction of a range of stimuli. Most notable among these is Sonic Hedgehog. In this article we briefly summarize the structure and biogenesis of primary cilia. We discuss the evidence implicating cilia in the transduction of extrinsic signals. We focus on the involvement and molecular mechanism of cilia in signaling by Sonic Hedgehog in embryonic tissues, specifically the neural tube, and we discuss how cilia play an active role in the interpretation of gradients of Sonic Hedgehog (Shh) signaling.
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Affiliation(s)
- Noriaki Sasai
- Developmental Biology, National Institute for Medical Research, Mill Hill, London, UK
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24
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Ryan KE, Chiang C. Hedgehog secretion and signal transduction in vertebrates. J Biol Chem 2012; 287:17905-13. [PMID: 22474285 DOI: 10.1074/jbc.r112.356006] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Signaling by the Hedgehog (Hh) family of secreted proteins is essential for proper embryonic patterning and development. Dysregulation of Hh signaling is associated with a variety of human diseases ranging from developmental disorders such as holoprosencephaly to certain forms of cancer, including medulloblastoma and basal cell carcinoma. Genetic studies in flies and mice have shaped our understanding of Hh signaling and revealed that nearly all core components of the pathway are highly conserved. Although many aspects of the Drosophila Hh pathway are conserved in vertebrates, mechanistic differences between the two species have begun to emerge. Perhaps the most striking divergence in vertebrate Hh signaling is its dependence on the primary cilium, a vestigial organelle that is largely absent in flies. This minireview will provide an overview of Hh signaling and present recent insights into vertebrate Hh secretion, receptor binding, and signal transduction.
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Affiliation(s)
- Kaitlyn E Ryan
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee 37232, USA
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25
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Klejnot M, Kozielski F. Structural insights into human Kif7, a kinesin involved in Hedgehog signalling. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2012; 68:154-9. [PMID: 22281744 PMCID: PMC3266853 DOI: 10.1107/s0907444911053042] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 12/09/2011] [Indexed: 02/16/2023]
Abstract
Kif7, a member of the kinesin 4 superfamily, is implicated in a variety of diseases including Joubert, hydrolethalus and acrocallosal syndromes. It is also involved in primary cilium formation and the Hedgehog signalling pathway and may play a role in cancer. Its activity is crucial for embryonic development. Kif7 and Kif27, a closely related kinesin in the same subfamily, are orthologues of the Drosophila melanogaster kinesin-like protein Costal-2 (Cos2). In vertebrates, they work together to fulfil the role of the single Cos2 gene in Drosophila. Here, the high-resolution structure of the human Kif7 motor domain is reported and is compared with that of conventional kinesin, the founding member of the kinesin superfamily. These data are a first step towards structural characterization of a kinesin-4 family member and of this interesting molecular motor of medical significance.
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Affiliation(s)
- Marta Klejnot
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow G61 1BD, Scotland
| | - Frank Kozielski
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow G61 1BD, Scotland
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26
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Abstract
Cilia and flagella play important roles in human health by contributing to cellular motility as well as sensing and responding to environmental cues. Defects in ciliary assembly and/or function can lead to a range of human diseases, collectively known as the ciliopathies, including polycystic kidney, liver and pancreatic diseases, sterility, obesity, situs inversus, hydrocephalus and retinal degeneration. A basic understanding of how cilia form and function is essential for deciphering ciliopathies and generating therapeutic treatments. The cilium is a unique compartment that contains a distinct complement of protein and lipid. However, the molecular mechanisms by which soluble and membrane protein components are targeted to and trafficked into the cilium are not well understood. Cilia are generated and maintained by IFT (intraflagellar transport) in which IFT cargoes are transported along axonemal microtubules by kinesin and dynein motors. A variety of genetic, biochemical and cell biological approaches has established the heterotrimeric kinesin-2 motor as the 'core' IFT motor, whereas other members of the kinesin-2, kinesin-3 and kinesin-4 families function as 'accessory' motors for the transport of specific cargoes in diverse cell types. Motors of the kinesin-9 and kinesin-13 families play a non-IFT role in regulating ciliary beating or axonemal length, respectively. Entry of kinesin motors and their cargoes into the ciliary compartment requires components of the nuclear import machinery, specifically importin-β2 (transportin-1) and Ran-GTP (Ran bound to GTP), suggesting that similar mechanisms may regulate entry into the nuclear and ciliary compartments.
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27
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Ben J, Elworthy S, Ng ASM, van Eeden F, Ingham PW. Targeted mutation of the talpid3 gene in zebrafish reveals its conserved requirement for ciliogenesis and Hedgehog signalling across the vertebrates. Development 2011; 138:4969-78. [PMID: 22028029 DOI: 10.1242/dev.070862] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Using zinc-finger nuclease-mediated mutagenesis, we have generated mutant alleles of the zebrafish orthologue of the chicken talpid3 (ta3) gene, which encodes a centrosomal protein that is essential for ciliogenesis. Animals homozygous for these mutant alleles complete embryogenesis normally, but manifest a cystic kidney phenotype during the early larval stages and die within a month of hatching. Elimination of maternally derived Ta3 activity by germline replacement resulted in embryonic lethality of ta3 homozygotes. The phenotype of such maternal and zygotic (MZta3) mutant zebrafish showed strong similarities to that of chick ta3 mutants: absence of primary and motile cilia as well as aberrant Hedgehog (Hh) signalling, the latter manifest by the expanded domains of engrailed and ptc1 expression in the somites, reduction of nkx2.2 expression in the neural tube, symmetric pectoral fins, cyclopic eyes and an ectopic lens. GFP-tagged Gli2a localised to the basal bodies in the absence of the primary cilia and western blot analysis showed that Gli2a protein is aberrantly processed in MZta3 embryos. Zygotic expression of ta3 largely rescued the effects of maternal depletion, but the motile cilia of Kupffer's vesicle remained aberrant, resulting in laterality defects. Our findings underline the importance of the primary cilium for Hh signaling in zebrafish and reveal the conservation of Ta3 function during vertebrate evolution.
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Affiliation(s)
- Jin Ben
- Developmental and Biomedical Genetics Group, Institute of Molecular & Cell Biology, Proteos, 61 Biopolis Drive, Singapore 138673, Republic of Singapore
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28
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Roy S. Cilia and Hedgehog: when and how was their marriage solemnized? Differentiation 2011; 83:S43-8. [PMID: 22154138 DOI: 10.1016/j.diff.2011.11.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 11/17/2011] [Accepted: 11/20/2011] [Indexed: 12/21/2022]
Abstract
Primary cilia are essential for Hedgehog (Hh) signaling in mammals, and this requirement appears to be conserved in other vertebrates as well. Here, I review recent work that has scrutinized the evolution of the link between the Hh pathway and cilia, discuss what we have learnt from these studies and speculate on how this fascinating problem can be further explored.
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Affiliation(s)
- Sudipto Roy
- Institute of Molecular and Cell Biology, Proteos, 61 Biopolis Drive, Singapore 138673, Singapore.
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29
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Abstract
Gli zinc-finger proteins are transcription factors involved in the intracellular signal transduction controlled by the Hedgehog family of secreted molecules. They are frequently mutated in human congenital malformations, and their abnormal regulation leads to tumorigenesis. Genetic studies in several model systems indicate that their activity is tightly regulated by Hedgehog signaling through various posttranslational modifications, including phosphorylation, ubiquitin-mediated degradation, and proteolytic processing, as well as through nucleocytoplasmic shuttling. In vertebrate cells, primary cilia are required for the sensing of Hedgehog pathway activity and involved in the processing and activation of Gli proteins. Two evolutionarily conserved Hedgehog pathway components, Suppressor of fused and Kif7, are core intracellular regulators of mammalian Gli proteins. Recent studies revealed that Gli proteins are also regulated transcriptionally and posttranslationally through noncanonical mechanisms independent of Hedgehog signaling. In this review, we describe the regulation of Gli proteins during development and discuss possible mechanisms for their abnormal activation during tumorigenesis.
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Affiliation(s)
- Chi-Chung Hui
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.
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31
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KIF7 mutations cause fetal hydrolethalus and acrocallosal syndromes. Nat Genet 2011; 43:601-6. [PMID: 21552264 DOI: 10.1038/ng.826] [Citation(s) in RCA: 164] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 04/08/2011] [Indexed: 12/24/2022]
Abstract
KIF7, the human ortholog of Drosophila Costal2, is a key component of the Hedgehog signaling pathway. Here we report mutations in KIF7 in individuals with hydrolethalus and acrocallosal syndromes, two multiple malformation disorders with overlapping features that include polydactyly, brain abnormalities and cleft palate. Consistent with a role of KIF7 in Hedgehog signaling, we show deregulation of most GLI transcription factor targets and impaired GLI3 processing in tissues from individuals with KIF7 mutations. KIF7 is also a likely contributor of alleles across the ciliopathy spectrum, as sequencing of a diverse cohort identified several missense mutations detrimental to protein function. In addition, in vivo genetic interaction studies indicated that knockdown of KIF7 could exacerbate the phenotype induced by knockdown of other ciliopathy transcripts. Our data show the role of KIF7 in human primary cilia, especially in the Hedgehog pathway through the regulation of GLI targets, and expand the clinical spectrum of ciliopathies.
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32
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Wilson CW, Chuang PT. Mechanism and evolution of cytosolic Hedgehog signal transduction. Development 2010; 137:2079-94. [PMID: 20530542 DOI: 10.1242/dev.045021] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Hedgehog (Hh) signaling is required for embryonic patterning and postnatal physiology in invertebrates and vertebrates. With the revelation that the primary cilium is crucial for mammalian Hh signaling, the prevailing view that Hh signal transduction mechanisms are conserved across species has been challenged. However, more recent progress on elucidating the function of core Hh pathway cytosolic regulators in Drosophila, zebrafish and mice has confirmed that the essential logic of Hh transduction is similar between species. Here, we review Hh signaling events at the membrane and in the cytosol, and focus on parallel and divergent functions of cytosolic Hh regulators in Drosophila and mammals.
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Affiliation(s)
- Christopher W Wilson
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
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33
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Goetz SC, Anderson KV. The primary cilium: a signalling centre during vertebrate development. Nat Rev Genet 2010; 11:331-44. [PMID: 20395968 DOI: 10.1038/nrg2774] [Citation(s) in RCA: 1386] [Impact Index Per Article: 99.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The primary cilium has recently stepped into the spotlight, as a flood of data show that this organelle has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialized for hedgehog signal transduction. The formation of cilia, in turn, is regulated by other signalling pathways, possibly including the planar cell polarity pathway. The cilium therefore represents a nexus for signalling pathways during development. The connections between cilia and developmental signalling have begun to clarify the basis of human diseases associated with ciliary dysfunction.
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Affiliation(s)
- Sarah C Goetz
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York 10065, USA
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34
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Kim HR, Richardson J, van Eeden F, Ingham PW. Gli2a protein localization reveals a role for Iguana/DZIP1 in primary ciliogenesis and a dependence of Hedgehog signal transduction on primary cilia in the zebrafish. BMC Biol 2010; 8:65. [PMID: 20487519 PMCID: PMC2890509 DOI: 10.1186/1741-7007-8-65] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Accepted: 04/19/2010] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND In mammalian cells, the integrity of the primary cilium is critical for proper regulation of the Hedgehog (Hh) signal transduction pathway. Whether or not this dependence on the primary cilium is a universal feature of vertebrate Hedgehog signalling has remained contentious due, in part, to the apparent divergence of the intracellular transduction pathway between mammals and teleost fish. RESULTS Here, using a functional Gli2-GFP fusion protein, we show that, as in mammals, the Gli2 transcription factor localizes to the primary cilia of cells in the zebrafish embryo and that this localization is modulated by the activity of the Hh pathway. Moreover, we show that the Igu/DZIP1protein, previously implicated in the modulation of Gli activity in zebrafish, also localizes to the primary cilium and is required for its proper formation. CONCLUSION Our findings demonstrate a conserved role of the primary cilium in mediating Hedgehog signalling activity across the vertebrate phylum and validate the use of the zebrafish as a representative model for the in vivo analysis of vertebrate Hedgehog signalling.
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Affiliation(s)
- Hyejeong Rosemary Kim
- MRC Centre for Developmental & Biomedical Genetics, University of Sheffield, Sheffield S10 2TN, UK
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35
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Abstract
Recent reports examining the mammalian kinesin relative Kif7 highlight the conserved role for microtubule motor proteins in Drosophila and vertebrate Hedgehog signalling. Mammalian Kif7 action centres at the primary cilium, an organelle absent from Drosophila. These studies raise interesting questions about the coupling of microtubule trafficking to the Hedgehog pathway.
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Affiliation(s)
- Philip W Ingham
- Institute of Molecular and Cellular Biology, 61, Biopolis Drive, Proteos, Singapore.
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36
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Rink JC, Gurley KA, Elliott SA, Sánchez Alvarado A. Planarian Hh signaling regulates regeneration polarity and links Hh pathway evolution to cilia. Science 2009; 326:1406-10. [PMID: 19933103 DOI: 10.1126/science.1178712] [Citation(s) in RCA: 185] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Hedgehog (Hh) signaling pathway plays multiple essential roles during metazoan development, homeostasis, and disease. Although core protein components are highly conserved, the variations in Hh signal transduction mechanisms exhibited by existing model systems (Drosophila, fish, and mammals) are difficult to understand. We characterized the Hh pathway in planarians. Hh signaling is essential for establishing the anterior/posterior axis during regeneration by modulating wnt expression. Moreover, RNA interference methods to reduce signal transduction proteins Cos2/Kif27/Kif7, Fused, or Iguana do not result in detectable Hh signaling defects; however, these proteins are essential for planarian ciliogenesis. Our study expands the understanding of Hh signaling in the animal kingdom and suggests an ancestral mechanistic link between Hh signaling and the function of cilia.
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Affiliation(s)
- Jochen C Rink
- Department of Neurobiology and Anatomy, Howard Hughes Medical Institute, University of Utah School of Medicine, 401 MREB, 20 North 1900 East, Salt Lake City, UT 84103, USA
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37
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Lunt SC, Haynes T, Perkins BD. Zebrafish ift57, ift88, and ift172 intraflagellar transport mutants disrupt cilia but do not affect hedgehog signaling. Dev Dyn 2009; 238:1744-59. [PMID: 19517571 DOI: 10.1002/dvdy.21999] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cilia formation requires intraflagellar transport (IFT) proteins. Recent studies indicate that mammalian Hedgehog (Hh) signaling requires cilia. It is unclear, however, if the requirement for cilia and IFT proteins in Hh signaling represents a general rule for all vertebrates. Here we examine zebrafish ift57, ift88, and ift172 mutants and morphants for defects in Hh signaling. Although ift57 and ift88 mutants and morphants contained residual maternal protein, the cilia were disrupted. In contrast to previous genetic studies in mouse, mutations in zebrafish IFT genes did not affect the expression of Hh target genes in the neural tube and forebrain and had no quantitative effect on Hh target gene expression. Zebrafish IFT mutants also exhibited no dramatic changes in the craniofacial skeleton, somite formation, or motor neuron patterning. Thus, our data indicate the requirement for cilia in the Hh signal transduction pathway may not represent a universal mechanism in vertebrates.
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Affiliation(s)
- Shannon C Lunt
- Department of Biology, Texas A&M University, College Station, Texas 77843, USA
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38
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Ruel L, Thérond PP. Variations in Hedgehog signaling: divergence and perpetuation in Sufu regulation of Gli. Genes Dev 2009; 23:1843-8. [PMID: 19684109 DOI: 10.1101/gad.1838109] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The Hedgehog (Hh) proteins play a universal role in metazoan development. Nevertheless, fundamental differences exist between Drosophila and vertebrates in the transduction of the Hh signal, notably regarding the role of primary cilia in mammalian cells. In this issue of Genes & Development, Chen and colleagues (pp. 1910-1928) demonstrate that mouse Suppressor of fused (Sufu) regulates the stability of the transcription factors Gli2 and Gli3 by antagonizing the conserved Gli degradation device mediated by Hib/Spop in a cilia-independent manner.
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Affiliation(s)
- Laurent Ruel
- Institut Biologie du Développement et Cancer-IBDC, Université de Nice-Sophia Antipolis, CNRS UMR 6543, Centre de Biochimie, Nice Cedex 02, France
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39
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Mouse Kif7/Costal2 is a cilia-associated protein that regulates Sonic hedgehog signaling. Proc Natl Acad Sci U S A 2009; 106:13377-82. [PMID: 19666503 DOI: 10.1073/pnas.0906944106] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Mammalian Sonic hedgehog (Shh) signaling is essential for embryonic development and stem cell maintenance and has critical roles in tumorigenesis. Although core components of the Shh pathway are conserved in evolution, important aspects of mammalian Shh signaling are not shared with the Drosophila pathway. Perhaps the most dramatic difference between the Drosophila and mammalian pathways is that Shh signaling in the mouse requires a microtubule-based organelle, the primary cilium. Proteins that are required for the response to Shh are enriched in the cilium, but it is not clear why the cilium provides an appropriate venue for signal transduction. Here, we demonstrate that Kif7, a mammalian homologue of Drosophila Costal2 (Cos2), is a cilia-associated protein that regulates signaling from the membrane protein Smoothened (Smo) to Gli transcription factors. By using a Kif7 mutant allele identified in a reporter-based genetic screen, we show that, similar to Drosophila and zebrafish Cos2, mouse Kif7 acts downstream of Smo and upstream of Gli2 and has both negative and positive roles in Shh signal transduction. Mouse Kif7 activity depends on the presence of cilia and Kif7-eGFP localizes to base of the primary cilium in the absence of Shh. Activation of the Shh pathway promotes trafficking of Kif7-eGFP from the base to the tip of the cilium, and localization to the tip of the cilium is disrupted in a motor domain mutant. We conclude that Kif7 is a core regulator of Shh signaling that may also act as a ciliary motor.
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40
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Medina V, Calvo MB, Díaz-Prado S, Espada J. Hedgehog signalling as a target in cancer stem cells. Clin Transl Oncol 2009; 11:199-207. [PMID: 19380296 DOI: 10.1007/s12094-009-0341-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Hedgehog (Hh) is one of the most important signalling pathways. Together with the Wnt, TGF-Beta/BMP and Notch pathways, it is involved in both embryonic development and adult tissue homeostasis. This is because Hh plays a central role in the proliferative control and differentiation of both embryonic stem cells and adult stem cells. In this way, an alteration in the Hh pathway, either by misexpression of components of that pathway or by changes in the expression of other cellular components that interfere with the Hh signalling system, may trigger the development of several types of cancer. This occurs because normal stem cells or their intermediaries toward differentiated mature cells are not part of the normal proliferative/ differentiation balance and begin to expand without control, triggering the generation of the so-called cancer stem cells. In this review, we will focus on the molecular aspects and the role of Hh signalling in normal tissues and in tumour development.
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Affiliation(s)
- Vanessa Medina
- Oncology Research Unit, University Hospital A Coruña, A Coruña, Spain.
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41
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Endoh-Yamagami S, Evangelista M, Wilson D, Wen X, Theunissen JW, Phamluong K, Davis M, Scales SJ, Solloway MJ, de Sauvage FJ, Peterson AS. The mammalian Cos2 homolog Kif7 plays an essential role in modulating Hh signal transduction during development. Curr Biol 2009; 19:1320-6. [PMID: 19592253 DOI: 10.1016/j.cub.2009.06.046] [Citation(s) in RCA: 172] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 06/19/2009] [Accepted: 06/22/2009] [Indexed: 11/19/2022]
Abstract
The Hedgehog (Hh) signaling pathway regulates development in animals ranging from flies to humans. Although its framework is conserved, differences in pathway components have been reported. A kinesin-like protein, Costal2 (Cos2), plays a central role in the Hh pathway in flies. Knockdown of a zebrafish homolog of Cos2, Kif7, results in ectopic Hh signaling, suggesting that Kif7 acts primarily as a negative regulator of Hh signal transduction. However, in vitro analysis of the function of mammalian Kif7 and the closely related Kif27 has led to the conclusion that neither protein has a role in Hh signaling. Using Kif7 knockout mice, we demonstrate that mouse Kif7, like its zebrafish and Drosophila homologs, plays a role in transducing the Hh signal. We show that Kif7 accumulates at the distal tip of the primary cilia in a Hh-dependent manner. We also demonstrate a requirement for Kif7 in the efficient localization of Gli3 to cilia in response to Hh and for the processing of Gli3 to its repressor form. These results suggest a role for Kif7 in coordinating Hh signal transduction at the tip of cilia and preventing Gli3 cleavage into a repressor form in the presence of Hh.
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Affiliation(s)
- Setsu Endoh-Yamagami
- Department of Molecular Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
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42
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Cheung HOL, Zhang X, Ribeiro A, Mo R, Makino S, Puviindran V, Law KKL, Briscoe J, Hui CC. The kinesin protein Kif7 is a critical regulator of Gli transcription factors in mammalian hedgehog signaling. Sci Signal 2009; 2:ra29. [PMID: 19549984 DOI: 10.1126/scisignal.2000405] [Citation(s) in RCA: 164] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
From insects to humans, the Hedgehog (Hh) signaling pathway has conserved roles in embryonic development and tissue homeostasis. However, it has been suggested that the lack of mammalian equivalents of Costal2 (Cos2) contributes to a divergence between the mechanism of Drosophila and mammalian Hh signal transduction. Here, we challenge this view by showing that the kinesin protein Kif7 is a critical regulator of Hh signaling in mice. Similar to Cos2, Kif7 physically interacted with Gli transcription factors and controlled their proteolysis and stability, and acted both positively and negatively in Hh signaling. Thus, Kif7 is a missing component of the mammalian Hh signaling machinery, implying a greater commonality between the Drosophila and mammalian system than the prevailing view suggests.
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Affiliation(s)
- Helen Oi-Lam Cheung
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
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43
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Wilson CW, Nguyen CT, Chen MH, Yang JH, Gacayan R, Huang J, Chen JN, Chuang PT. Fused has evolved divergent roles in vertebrate Hedgehog signalling and motile ciliogenesis. Nature 2009; 459:98-102. [PMID: 19305393 DOI: 10.1038/nature07883] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Accepted: 02/10/2009] [Indexed: 12/23/2022]
Abstract
Hedgehog (Hh) signalling is essential for several aspects of embryogenesis. In Drosophila, Hh transduction is mediated by a cytoplasmic signalling complex that includes the putative serine-threonine kinase Fused (Fu) and the kinesin Costal 2 (Cos2, also known as Cos), yet Fu does not have a conserved role in Hh signalling in mammals. Mouse Fu (also known as Stk36) mutants are viable and seem to respond normally to Hh signalling. Here we show that mouse Fu is essential for construction of the central pair apparatus of motile, 9+2 cilia and offers a new model of human primary ciliary dyskinesia. We found that mouse Fu physically interacts with Kif27, a mammalian Cos2 orthologue, and linked Fu to known structural components of the central pair apparatus, providing evidence for the first regulatory component involved in central pair construction. We also demonstrated that zebrafish Fu is required both for Hh signalling and cilia biogenesis in Kupffer's vesicle. Mouse Fu rescued both Hh-dependent and -independent defects in zebrafish. Our results delineate a new pathway for central pair apparatus assembly, identify common regulators of Hh signalling and motile ciliogenesis, and provide insights into the evolution of the Hh cascade.
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Affiliation(s)
- Christopher W Wilson
- Cardiovascular Research Institute, University of California, San Francisco, California 94158, USA
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44
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Simpson F, Kerr MC, Wicking C. Trafficking, development and hedgehog. Mech Dev 2009; 126:279-88. [PMID: 19368798 DOI: 10.1016/j.mod.2009.01.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 01/22/2009] [Accepted: 01/26/2009] [Indexed: 11/27/2022]
Abstract
Embryogenesis is mediated by a relatively small number of developmental signaling pathways, and the morphogens, receptors and transcription factors integral to these cascades are considered the master regulators of development. However, superimposed on this is an additional layer of control by complex intracellular trafficking networks. The importance of trafficking in controlling the processes of morphogenesis and development is highlighted by recent data regarding the transport and localisation of the morphogen sonic hedgehog (Shh) and the machinery that leads to its secretion, modification, cellular internalisation and signal transduction. Here we review the regulation of hedgehog signaling by intracellular trafficking, including the role of the primary cilium and lipids in mediating pathway activity.
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Affiliation(s)
- Fiona Simpson
- The University of Queensland, Institute for Molecular Bioscience, Qld, Australia
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45
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Abstract
The Hedgehog (Hh) family of secreted proteins governs a wide variety of processes during embryonic development and adult tissue homeostasis. Here we review the current understanding of the molecular and cellular basis of Hh morphogen gradient formation and signal transduction, and the multifaceted roles of Hh signaling in development and tumorigenesis. We discuss how the Hh pathway has diverged during evolution and how it integrates with other signaling pathways to control cell growth and patterning.
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Affiliation(s)
- Jin Jiang
- Department of Developmental Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA.
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46
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Abstract
This chapter describes how to perform basic biochemical fractionations of Drosophila cells, and how to begin to characterize the proteins in the resulting fractions. The protocols include maintenance and transfection of Drosophila cell lines (Section 3.1.), hypotonic lysis (Section 3.2.), and separation of cellular lysates into cytosolic and membrane enriched fractions (Section 3.3.). Cytosolic proteins and those extracted from the membrane enriched fraction can be characterized by size exclusion liquid chromatography (Section 3.4.),while the membrane enriched fraction can be subjected to equilibrium density centrifugation to separate different types of cellular membranes from dense, nonmembranous cellular components (Section 3.5.). The resulting fractions can be used to examine the subcellular localization of a given protein, or the activity of a given protein in various subcellular localizations. When the protein of interest is involved in a signaling pathway, its subcellular localization can provide insight into its mechanism of action in the pathway.
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47
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Philipp M, Fralish GB, Meloni AR, Chen W, MacInnes AW, Barak LS, Caron MG. Smoothened signaling in vertebrates is facilitated by a G protein-coupled receptor kinase. Mol Biol Cell 2008; 19:5478-89. [PMID: 18815277 DOI: 10.1091/mbc.e08-05-0448] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Smoothened, a heptahelical membrane protein, functions as the transducer of Hedgehog signaling. The kinases that modulate Smoothened have been thoroughly analyzed in flies. However, little is known about how phosphorylation affects Smoothened in vertebrates, mainly, because the residues, where Smoothened is phosphorylated are not conserved from Drosophila to vertebrates. Given its molecular architecture, Smoothened signaling is likely to be regulated in a manner analogous to G protein-coupled receptors (GPCRs). Previously, it has been shown, that arrestins and GPCR kinases, (GRKs) not only desensitize G protein-dependent receptor signaling but also function as triggers for GPCR trafficking and formation of signaling complexes. Here we describe that a GRK contributes to Smoothened-mediated signaling in vertebrates. Knockdown of the zebrafish homolog of mammalian GRK2/3 results in lowered Hedgehog transcriptional responses, impaired muscle development, and neural patterning. Results obtained in zebrafish are corroborated both in cell culture, where zGRK2/3 phosphorylates Smoothened and promotes Smoothened signal transduction and in mice where deletion of GRK2 interferes with neural tube patterning. Together, these data suggest that a GRK functions as a vertebrate kinase for Smoothened, promoting Hedgehog signal transduction during early development.
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Affiliation(s)
- Melanie Philipp
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
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48
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Dessaud E, McMahon AP, Briscoe J. Pattern formation in the vertebrate neural tube: a sonic hedgehog morphogen-regulated transcriptional network. Development 2008; 135:2489-503. [PMID: 18621990 DOI: 10.1242/dev.009324] [Citation(s) in RCA: 512] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Neuronal subtype specification in the vertebrate neural tube is one of the best-studied examples of embryonic pattern formation. Distinct neuronal subtypes are generated in a precise spatial order from progenitor cells according to their location along the anterior-posterior and dorsal-ventral axes. Underpinning this organization is a complex network of multiple extrinsic and intrinsic factors. This review focuses on the molecular mechanisms and general strategies at play in ventral regions of the forming spinal cord, where sonic hedgehog-based morphogen signaling is a key determinant. We discuss recent advances in our understanding of these events and highlight unresolved questions.
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Affiliation(s)
- Eric Dessaud
- Developmental Neurobiology, National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK
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49
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The role of kinases in the Hedgehog signalling pathway. EMBO Rep 2008; 9:330-6. [PMID: 18379584 DOI: 10.1038/embor.2008.38] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 02/21/2008] [Indexed: 11/08/2022] Open
Abstract
The Hedgehog (Hh) signalling pathway has a crucial role in several developmental processes and is aberrantly activated in a variety of cancers. In Drosophila, many of the canonical Hh pathway components are phosphorylated, yet the precise role of these phosphorylation events in the regulation of Hh signal transduction is unclear. Furthermore, the Hh pathway receives input from several kinases that have well-described roles in other cellular functions, some of which have both positive and negative effects on Hh signalling. Several recent studies have characterized the role of specific phosphorylation events in the Hh pathway, and have begun to shed light on how phosphorylation of Hh signalling components affects their subcellular location, stability and activity to mediate the transcriptional response to the Hh gradient.
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50
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Ho NY, Li VWT, Poon WL, Cheng SH. Cloning and developmental expression of kinesin superfamily7 (kif7) in the brackish medaka (Oryzias melastigma), a close relative of the Japanese medaka (Oryzias latipes). MARINE POLLUTION BULLETIN 2008; 57:425-432. [PMID: 18423496 DOI: 10.1016/j.marpolbul.2008.02.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Revised: 02/19/2008] [Accepted: 02/26/2008] [Indexed: 05/26/2023]
Abstract
kif7 is a member of the kinesin superfamily members which are molecular motor proteins that move along microtubules in a highly regulated manner through ATP hydrolysis. In this paper, we report on the cloning of the Oryziasmelastigmakif7 (omkif7) using primers designed according to the Japanese medaka (Oryziaslatipes) database. The cloned omkif7 has an open reading frame of 3762bp and is deduced to encode a polypeptide of 1254 amino acids that possesses the putative ATP-binding and microtubule-binding motifs in its motor domain at the N-terminal region. We characterized the cloned omkif7 by comparison with the zebrafish kif7. Both omkif7 and zebrafish kif7 are shown to be expressed in all embryonic stages and adult tissues examined with higher expression level in the testis and ovary. Whole-mount in situ hybridization revealed that the expression of omkif7 is ubiquitous during the early stages of embryonic development, but became more restrictive and localized to the brain, fin bud and eye at later development. This study suggested that the brackish O.melastigma can serve as a good seawater model organism for developmental studies by utilizing the resources developed from its close relative of the Japanese medaka.
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Affiliation(s)
- Nga Yu Ho
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
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