201
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Yang TT, Chong WM, Wang WJ, Mazo G, Tanos B, Chen Z, Tran TMN, Chen YD, Weng RR, Huang CE, Jane WN, Tsou MFB, Liao JC. Super-resolution architecture of mammalian centriole distal appendages reveals distinct blade and matrix functional components. Nat Commun 2018; 9:2023. [PMID: 29789620 PMCID: PMC5964178 DOI: 10.1038/s41467-018-04469-1] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 04/30/2018] [Indexed: 12/14/2022] Open
Abstract
Distal appendages (DAPs) are nanoscale, pinwheel-like structures protruding from the distal end of the centriole that mediate membrane docking during ciliogenesis, marking the cilia base around the ciliary gate. Here we determine a super-resolved multiplex of 16 centriole-distal-end components. Surprisingly, rather than pinwheels, intact DAPs exhibit a cone-shaped architecture with components filling the space between each pinwheel blade, a new structural element we term the distal appendage matrix (DAM). Specifically, CEP83, CEP89, SCLT1, and CEP164 form the backbone of pinwheel blades, with CEP83 confined at the root and CEP164 extending to the tip near the membrane-docking site. By contrast, FBF1 marks the distal end of the DAM near the ciliary membrane. Strikingly, unlike CEP164, which is essential for ciliogenesis, FBF1 is required for ciliary gating of transmembrane proteins, revealing DAPs as an essential component of the ciliary gate. Our findings redefine both the structure and function of DAPs. Distal appendages (DAPs) at the cilia base mediate membrane docking during ciliogenesis. Here the authors use super-resolution microscopy to map 16 centriole distal end components, revealing the structure of the backbone of the DAP, as well as a previously undescribed distal appendage matrix.
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Affiliation(s)
- T Tony Yang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Weng Man Chong
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Won-Jing Wang
- Institute of Biochemistry and Molecular Biology, National Yang Ming University, Taipei, 11221, Taiwan
| | - Gregory Mazo
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, 10065, USA
| | | | - Zhengmin Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Thi Minh Nguyet Tran
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan.,Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Yi-De Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Rueyhung Roc Weng
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan.,Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Chia-En Huang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan.,TFBS Bioscience, Inc., Taipei, Taiwan
| | - Wann-Neng Jane
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Meng-Fu Bryan Tsou
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, 10065, USA.
| | - Jung-Chi Liao
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan. .,Genome and Systems Biology Degree Program, National Taiwan University, Taipei, 10617, Taiwan.
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202
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Revenkova E, Liu Q, Gusella GL, Iomini C. The Joubert syndrome protein ARL13B binds tubulin to maintain uniform distribution of proteins along the ciliary membrane. J Cell Sci 2018; 131:jcs212324. [PMID: 29592971 PMCID: PMC5992585 DOI: 10.1242/jcs.212324] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 03/23/2018] [Indexed: 01/09/2023] Open
Abstract
Cilia-mediated signal transduction involves precise targeting and localization of selected molecules along the ciliary membrane. However, the molecular mechanism underlying these events is unclear. The Joubert syndrome protein ARL13B is a membrane-associated G-protein that localizes along the cilium and functions in protein transport and signaling. We identify tubulin as a direct interactor of ARL13B and demonstrate that the association occurs via the G-domain and independently from the GTPase activity of ARL13B. The G-domain is necessary for the interaction of ARL13B with the axoneme both in vitro and in vivo We further show that exogenously expressed mutants lacking the tubulin-binding G-domain (ARL13B-ΔGD) or whose GTPase domain is inactivated (ARL13B-T35N) retain ciliary localization, but fail to rescue ciliogenesis defects of null Arl13bhnn mouse embryonic fibroblasts (MEFs). However, while ARL13B-ΔGD and the membrane proteins Smoothened (SMO) and Somatostatin receptor-3 (SSTR3) distribute unevenly along the cilium of Arl13bhnn MEFs, ARL13B-T35N distributes evenly along the cilium and enables the uniform distribution of SMO and SSTR3. Thus, we propose a so far unknown function of ARL13B in anchoring ciliary membrane proteins to the axoneme through the direct interaction of its G-domain with tubulin.
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Affiliation(s)
- Ekaterina Revenkova
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Qing Liu
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - G Luca Gusella
- Department of Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Carlo Iomini
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
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203
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Hor CH, Tang BL, Goh EL. Rab23 and developmental disorders. Rev Neurosci 2018; 29:849-860. [DOI: 10.1515/revneuro-2017-0110] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/03/2018] [Indexed: 02/07/2023]
Abstract
Abstract
Rab23 is a conserved member of the Rab family of small GTPases that regulates membrane trafficking in eukaryotes. It is unique amongst the Rabs in terms of its implicated role in mammalian development, as originally illustrated by the embryonic lethality and open neural tube phenotype of a spontaneous mouse mutant that carries homozygous mutation of open brain, a gene encoding Rab23. Rab23 was initially identified to act as an antagonist of Sonic hedgehog (Shh) signaling, and has since been implicated in a number of physiological and pathological roles, including oncogenesis. Interestingly, RAB23 null allele homozygosity in humans is not lethal, but instead causes the developmental disorder Carpenter’s syndrome (CS), which is characterized by craniofacial malformations, polysyndactyly, obesity and intellectual disability. CS bears some phenotypic resemblance to a spectrum of hereditary defects associated with the primary cilium, or the ciliopathies. Recent findings have in fact implicated Rab23 in protein traffic to the primary cilium, thus linking it with the primary cellular locale of Shh signaling. Rab23 also has Shh and cilia-independent functions. It is known to mediate the expression of Nodal at the mouse left lateral plate mesoderm and Kupffer’s vesicle, the zebrafish equivalent of the mouse node. It is thus important for the left-right patterning of vertebrate embryos. In this review, we discuss the developmental disorders associated with Rab23 and attempt to relate its cellular activities to its roles in development.
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Affiliation(s)
- Catherine H.H. Hor
- Neuroscience Academic Clinical Programme, Duke-NUS Medical School , 8 College Road , Singapore 169857 , Singapore
- Department of Research , National Neuroscience Institute , Singapore 308433 , Singapore
| | - Bor Luen Tang
- Department of Biochemistry , Yong Loo Lin School of Medicine , National University of Singapore , Singapore 117597 , Singapore
- NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore, Medical Drive , Singapore 117456 , Singapore
| | - Eyleen L.K. Goh
- Neuroscience Academic Clinical Programme, Duke-NUS Medical School , 8 College Road , Singapore 169857 , Singapore
- Department of Research , National Neuroscience Institute , Singapore 308433 , Singapore
- Department of Physiology , Yong Loo Lin School of Medicine , National University of Singapore , 8 Medical Drive , Singapore 117597 , Singapore
- KK Research Center, KK Women’s and Children’s Hospital , Singapore 229899 , Singapore
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204
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Moye AR, Singh R, Kimler VA, Dilan TL, Munezero D, Saravanan T, Goldberg AFX, Ramamurthy V. ARL2BP, a protein linked to retinitis pigmentosa, is needed for normal photoreceptor cilia doublets and outer segment structure. Mol Biol Cell 2018; 29:1590-1598. [PMID: 29718757 PMCID: PMC6080659 DOI: 10.1091/mbc.e18-01-0040] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The outer segment (OS) of photoreceptor cells is an elaboration of a primary cilium with organized stacks of membranous disks that contain the proteins needed for phototransduction and vision. Though ciliary formation and function has been well characterized, little is known about the role of cilia in the development of photoreceptor OS. Nevertheless, progress has been made by studying mutations in ciliary proteins, which often result in malformed OSs and lead to blinding diseases. To investigate how ciliary proteins contribute to OS formation, we generated a knockout (KO) mouse model for ARL2BP, a ciliary protein linked to retinitis pigmentosa. The KO mice display an early and progressive reduction in visual response. Before photoreceptor degeneration, we observed disorganization of the photoreceptor OS, with vertically aligned disks and shortened axonemes. Interestingly, ciliary doublet microtubule (MT) structure was also impaired, displaying open B-tubule doublets, paired with loss of singlet MTs. On the basis of results from this study, we conclude that ARL2BP is necessary for photoreceptor ciliary doublet formation and axoneme elongation, which is required for OS morphogenesis and vision.
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Affiliation(s)
- Abigail R Moye
- Department of Ophthalmology, West Virginia University, Morgantown, WV 26506.,Department of Biochemistry, West Virginia University, Morgantown, WV 26506
| | - Ratnesh Singh
- Department of Biochemistry, West Virginia University, Morgantown, WV 26506
| | | | - Tanya L Dilan
- Department of Ophthalmology, West Virginia University, Morgantown, WV 26506.,Department of Biochemistry, West Virginia University, Morgantown, WV 26506
| | - Daniella Munezero
- Department of Ophthalmology, West Virginia University, Morgantown, WV 26506.,Department of Biochemistry, West Virginia University, Morgantown, WV 26506
| | | | | | - Visvanathan Ramamurthy
- Department of Ophthalmology, West Virginia University, Morgantown, WV 26506.,Department of Biochemistry, West Virginia University, Morgantown, WV 26506.,Rockefeller Neurosciences Institute, West Virginia University, Morgantown, WV 26506
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205
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Over-elongation of centrioles in cancer promotes centriole amplification and chromosome missegregation. Nat Commun 2018; 9:1258. [PMID: 29593297 PMCID: PMC5871873 DOI: 10.1038/s41467-018-03641-x] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 03/02/2018] [Indexed: 12/16/2022] Open
Abstract
Centrosomes are the major microtubule organising centres of animal cells. Deregulation in their number occurs in cancer and was shown to trigger tumorigenesis in mice. However, the incidence, consequence and origins of this abnormality are poorly understood. Here, we screened the NCI-60 panel of human cancer cell lines to systematically analyse centriole number and structure. Our screen shows that centriole amplification is widespread in cancer cell lines and highly prevalent in aggressive breast carcinomas. Moreover, we identify another recurrent feature of cancer cells: centriole size deregulation. Further experiments demonstrate that severe centriole over-elongation can promote amplification through both centriole fragmentation and ectopic procentriole formation. Furthermore, we show that overly long centrioles form over-active centrosomes that nucleate more microtubules, a known cause of invasiveness, and perturb chromosome segregation. Our screen establishes centriole amplification and size deregulation as recurrent features of cancer cells and identifies novel causes and consequences of those abnormalities. Cancer cells are characterised by abnormalities in the number of centrosomes and this phenotype is linked with tumorigenesis. Here the authors report centriole length deregulation in a subset of cancer cell lines and suggest a link with subsequent alterations in centriole numbers and chromosomal instability.
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206
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Gigante ED, Long AB, Ben-Ami J, Caspary T. Hypomorphic Smo mutant with inefficient ciliary enrichment disrupts the highest level of vertebrate Hedgehog response. Dev Biol 2018; 437:152-162. [PMID: 29571613 DOI: 10.1016/j.ydbio.2018.03.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/04/2018] [Accepted: 03/20/2018] [Indexed: 12/31/2022]
Abstract
Smoothened (Smo) is the essential transducer of Sonic hedgehog (Shh) signaling, which regulates cell fate and proliferation during embryogenesis. We identified a novel mouse mutant, cabbie (cbb), and found that its cause is a missense mutation in Smo. We showed the Smocbb mutation is insensitive to the Shh agonist SAG, perhaps due to the disruption of SAG binding. We characterized Smocbb for defects in craniofacial and skeletal development, as well as neural tube patterning, and revealed Smocbb affected processes that require the highest levels of Shh activity. Smo is normally enriched in cilia upon Shh stimulation; however, we detected inefficient enrichment of Smo in Smocbb mutants whether we stimulated with Shh or SAG. Taken together, our data suggest that the highest levels of vertebrate Hedgehog signaling activity require efficient Smo ciliary enrichment.
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Affiliation(s)
- Eduardo D Gigante
- Neuroscience Graduate Program, Emory University, Atlanta, GA 30322, USA; Department of Human Genetics, Emory University, Atlanta, GA 30322, USA.
| | | | - Johanna Ben-Ami
- Department of Human Genetics, Emory University, Atlanta, GA 30322, USA; Emory College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA.
| | - Tamara Caspary
- Department of Human Genetics, Emory University, Atlanta, GA 30322, USA.
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207
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Quantitative Comparison of Primary Cilia Marker Expression and Length in the Mouse Brain. J Mol Neurosci 2018; 64:397-409. [PMID: 29464516 DOI: 10.1007/s12031-018-1036-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 01/31/2018] [Indexed: 12/12/2022]
Abstract
Primary cilia are small, special cellular organelles that provide important sensory and signaling functions during the development of mammalian organs and coordination of postnatal cellular processes. Dysfunction of primary cilia are thought to be the main cause of ciliopathies, a group of genetic disorders characterized by overlapping developmental defects and prominent neurodevelopmental features. Although, disrupted cilia-linked signaling pathways have been implicated in the regulation of numerous neuronal functions, the precise role of primary cilia in the brain are still unknown. Importantly, studies of recent years have highlighted that different functions of primary cilia are reflected by their diverse morphology and unique signaling components localized in the ciliary membrane. In the present study, we conducted a comparative analysis of the expression pattern, distribution and length of adenylyl cyclase 3, somatostatin receptor 3, and ADP-ribosylation factor-like protein 13B expressing primary cilia in the mouse brain. We show that cilia of neurons and astrocytes display a well characterized distribution and ciliary marker arrangements. Moreover, quantitative comparison of their length, density and occurrence rate revealed that primary cilia exhibit region-specific alternations. In summary, our study provides a comprehensive overview of the cellular organization and morphological traits of primary cilia in regions of the physiological adult mouse brain.
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208
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Bay SN, Long AB, Caspary T. Disruption of the ciliary GTPase Arl13b suppresses Sonic hedgehog overactivation and inhibits medulloblastoma formation. Proc Natl Acad Sci U S A 2018; 115:1570-1575. [PMID: 29378965 PMCID: PMC5816136 DOI: 10.1073/pnas.1706977115] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Medulloblastoma (MB) is the most common malignant pediatric brain tumor, and overactivation of the Sonic Hedgehog (Shh) signaling pathway, which requires the primary cilium, causes 30% of MBs. Current treatments have known negative side effects or resistance mechanisms, so new treatments are necessary. Shh signaling mutations, like those that remove Patched1 (Ptch1) or activate Smoothened (Smo), cause tumors dependent on the presence of cilia. Genetic ablation of cilia prevents these tumors by removing Gli activator, but cilia are a poor therapeutic target since they support many biological processes. A more appropriate strategy would be to identify a protein that functionally disentangles Gli activation and ciliogenesis. Our mechanistic understanding of the ciliary GTPase Arl13b predicts that it could be such a target. Arl13b mutants retain short cilia, and loss of Arl13b results in ligand-independent, constitutive, low-level pathway activation but prevents maximal signaling without disrupting Gli repressor. Here, we show that deletion of Arl13b reduced Shh signaling levels in the presence of oncogenic SmoA1, suggesting Arl13b acts downstream of known tumor resistance mechanisms. Knockdown of ARL13B in human MB cell lines and in primary mouse MB cell culture decreased proliferation. Importantly, loss of Arl13b in a Ptch1-deleted mouse model of MB inhibited tumor formation. Postnatal depletion of Arl13b does not lead to any overt phenotypes in the epidermis, liver, or cerebellum. Thus, our in vivo and in vitro studies demonstrate that disruption of Arl13b inhibits cilia-dependent oncogenic Shh overactivation.
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Affiliation(s)
- Sarah N Bay
- Department of Human Genetics, Emory University, Atlanta, GA 30322
- Genetics and Molecular Biology Program, Emory University, Atlanta, GA 30322
| | - Alyssa B Long
- Department of Human Genetics, Emory University, Atlanta, GA 30322
| | - Tamara Caspary
- Department of Human Genetics, Emory University, Atlanta, GA 30322;
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209
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Deficiency of primary cilia in kidney epithelial cells induces epithelial to mesenchymal transition. Biochem Biophys Res Commun 2018; 496:450-454. [DOI: 10.1016/j.bbrc.2018.01.079] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/11/2018] [Indexed: 01/15/2023]
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210
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Abstract
Despite therapeutic advances that have prolonged life, myocardial infarction (MI) remains a leading cause of death worldwide and imparts a significant economic burden. The advancement of treatments to improve cardiac repair post-MI requires the discovery of new targeted treatment strategies. Recent studies have highlighted the importance of the epicardial covering of the heart in both cardiac development and lower vertebrate cardiac regeneration. The epicardium serves as a source of cardiac cells including smooth muscle cells, endothelial cells and cardiac fibroblasts. Mammalian adult epicardial cells are typically quiescent. However, the fetal genetic program is reactivated post-MI, and epicardial epithelial-to-mesenchymal transition (EMT) occurs as an inherent mechanism to support neovascularization and cardiac healing. Unfortunately, endogenous EMT is not enough to encourage sufficient repair. Recent developments in our understanding of the mechanisms supporting the EMT process has led to a number of studies directed at augmenting epicardial EMT post-MI. With a focus on the role of the primary cilium, this review outlines the newly demonstrated mechanisms supporting EMT, the role of epicardial EMT in cardiac development, and promising advances in augmenting epicardial EMT as potential therapeutics to support cardiac repair post-MI.
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211
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Diamand KEM, Barratt KS, Arkell RM. Overview of Rodent Zic Genes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1046:179-207. [PMID: 29442323 DOI: 10.1007/978-981-10-7311-3_10] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The five murine Zic genes encode multifunctional transcriptional regulator proteins important for a large number of processes during embryonic development. The genes and proteins are highly conserved with respect to the orthologous human genes, an attribute evidently mirrored by functional conservation, since the murine and human genes mutate to give the same phenotypes. Each ZIC protein contains a zinc finger domain that participates in both protein-DNA and protein-protein interactions. The ZIC proteins are capable of interacting with the key transcriptional mediators of the SHH, WNT and NODAL signalling pathways as well as with components of the transcriptional machinery and chromatin-modifying complexes. It is possible that this diverse range of protein partners underlies characteristics uncovered by mutagenesis and phenotyping of the murine Zic genes. These features include redundant and unique roles for ZIC proteins, regulatory interdependencies amongst family members and pleiotropic Zic gene function. Future investigations into the complex nature of the Zic gene family activity should be facilitated by recent advances in genome engineering and functional genomics.
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Affiliation(s)
- Koula E M Diamand
- Early Mammalian Development Laboratory, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Kristen S Barratt
- Early Mammalian Development Laboratory, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Ruth M Arkell
- Early Mammalian Development Laboratory, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.
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212
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He M, Ye W, Wang WJ, Sison ES, Jan YN, Jan LY. Cytoplasmic Cl - couples membrane remodeling to epithelial morphogenesis. Proc Natl Acad Sci U S A 2017; 114:E11161-E11169. [PMID: 29229864 PMCID: PMC5748203 DOI: 10.1073/pnas.1714448115] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Chloride is the major free anion in the extracellular space (>100 mM) and within the cytoplasm in eukaryotes (10 ∼ 20 mM). Cytoplasmic Cl- level is dynamically regulated by Cl- channels and transporters. It is well established that movement of Cl- across the cell membrane is coupled with cell excitability through changes in membrane potential and with water secretion. However, whether cytoplasmic Cl- plays additional roles in animal development and tissue homeostasis is unknown. Here we use genetics, cell biological and pharmacological tools to demonstrate that TMEM16A, an evolutionarily conserved calcium-activated chloride channel (CaCC), regulates cytoplasmic Cl- homeostasis and promotes plasma membrane remodeling required for mammalian epithelial morphogenesis. We demonstrate that TMEM16A-mediated control of cytoplasmic Cl- regulates the organization of the major phosphoinositide species PtdIns(4,5)P2 into microdomains on the plasma membrane, analogous to processes that cluster soluble and membrane proteins into phase-separated droplets. We further show that an adequate cytoplasmic Cl- level is required for proper endocytic trafficking and membrane supply during early stages of ciliogenesis and adherens junction remodeling. Our study thus uncovers a critical function of CaCC-mediated cytoplasmic Cl- homeostasis in controlling the organization of PtdIns(4,5)P2 microdomains and membrane remodeling. This newly defined role of cytoplasmic Cl- may shed light on the mechanisms of intracellular Cl- signaling events crucial for regulating tissue architecture and organelle biogenesis during animal development.
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Affiliation(s)
- Mu He
- Department of Physiology, University of California, San Francisco, CA 94158
| | - Wenlei Ye
- Department of Physiology, University of California, San Francisco, CA 94158
| | - Won-Jing Wang
- Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei, 11221, Taiwan
| | - Eirish S Sison
- Department of Physiology, University of California, San Francisco, CA 94158
- Howard Hughes Medical Institute, University of California, San Francisco, CA 94158
| | - Yuh Nung Jan
- Department of Physiology, University of California, San Francisco, CA 94158
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158
- Howard Hughes Medical Institute, University of California, San Francisco, CA 94158
| | - Lily Yeh Jan
- Department of Physiology, University of California, San Francisco, CA 94158;
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158
- Howard Hughes Medical Institute, University of California, San Francisco, CA 94158
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213
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Rafiullah R, Long AB, Ivanova AA, Ali H, Berkel S, Mustafa G, Paramasivam N, Schlesner M, Wiemann S, Wade RC, Bolthauser E, Blum M, Kahn RA, Caspary T, Rappold GA. A novel homozygous ARL13B variant in patients with Joubert syndrome impairs its guanine nucleotide-exchange factor activity. Eur J Hum Genet 2017; 25:1324-1334. [PMID: 29255182 PMCID: PMC5865152 DOI: 10.1038/s41431-017-0031-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 10/02/2017] [Accepted: 10/10/2017] [Indexed: 11/09/2022] Open
Abstract
ARL13B encodes for the ADP-ribosylation factor-like 13B GTPase, which is required for normal cilia structure and Sonic hedgehog (Shh) signaling. Disruptions in cilia structure or function lead to a class of human disorders called ciliopathies. Joubert syndrome is characterized by a wide spectrum of symptoms, including a variable degree of intellectual disability, ataxia, and ocular abnormalities. Here we report a novel homozygous missense variant c.[223G>A] (p.(Gly75Arg) in the ARL13B gene, which was identified by whole-exome sequencing of a trio from a consanguineous family with multiple-affected individuals suffering from intellectual disability, ataxia, ocular defects, and epilepsy. The same variant was also identified in a second family. We saw a striking difference in the severity of ataxia between affected male and female individuals in both families. Both ARL13B and ARL13B-c.[223G>A] (p.(Gly75Arg) expression rescued the cilia length and Shh defects displayed by Arl13b hennin (null) cells, indicating that the variant did not disrupt either ARL13B function. In contrast, ARL13B-c.[223G>A] (p.(Gly75Arg) displayed a marked loss of ARL3 guanine nucleotide-exchange factor activity, with retention of its GTPase activities, highlighting the correlation between its loss of function as an ARL3 guanine nucleotide-exchange factor and Joubert syndrome.
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Affiliation(s)
- Rafiullah Rafiullah
- Department of Human Molecular Genetics, Heidelberg University, 69120, Heidelberg, Germany
| | - Alyssa B Long
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Anna A Ivanova
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Hazrat Ali
- Department of Psychiatry, Bolan Medical College, 87600, Quetta, Pakistan
| | - Simone Berkel
- Department of Human Molecular Genetics, Heidelberg University, 69120, Heidelberg, Germany
| | - Ghulam Mustafa
- Molecular and Cellular Modeling (MCM) Group, Heidelberg Institute for Theoretical Studies (HITS), 69118, Heidelberg, Germany
- Center for Molecular Biology, DKFZ-ZMBH Alliance, Heidelberg University, 69120, Heidelberg, Germany
| | - Nagarajan Paramasivam
- Computational Oncology Group, Theoretical Bioinformatics Division (B080), German Cancer Research Centre (DKFZ), 69120, Heidelberg, Germany
- Medical Faculty Heidelberg, Heidelberg University, 69120, Heidelberg, Germany
| | - Matthias Schlesner
- Computational Oncology Group, Theoretical Bioinformatics Division (B080), German Cancer Research Centre (DKFZ), 69120, Heidelberg, Germany
| | - Stefan Wiemann
- Genomic and Proteomics Core Facility, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany
| | - Rebecca C Wade
- Molecular and Cellular Modeling (MCM) Group, Heidelberg Institute for Theoretical Studies (HITS), 69118, Heidelberg, Germany
- Center for Molecular Biology, DKFZ-ZMBH Alliance, Heidelberg University, 69120, Heidelberg, Germany
| | - Eugen Bolthauser
- Division of Pediatric Neurology, University Children's Hospital, 8032, Zurich, Switzerland
| | - Martin Blum
- Institute of Zoology, University of Hohenheim, 70593, Stuttgart, Germany
| | - Richard A Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Gudrun A Rappold
- Department of Human Molecular Genetics, Heidelberg University, 69120, Heidelberg, Germany.
- Interdisciplinary Centre for Neurosciences (IZN), University of Heidelberg, 69120, Heidelberg, Germany.
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214
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Lupu FI, Burnett JB, Eggenschwiler JT. Cell cycle-related kinase regulates mammalian eye development through positive and negative regulation of the Hedgehog pathway. Dev Biol 2017; 434:24-35. [PMID: 29166577 DOI: 10.1016/j.ydbio.2017.10.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 01/20/2023]
Abstract
Cell cycle-related kinase (CCRK) is a conserved regulator of ciliogenesis whose loss in mice leads to a wide range of developmental defects, including exencephaly, preaxial polydactyly, skeletal abnormalities, and microphthalmia. Here, we investigate the role of CCRK in mouse eye development. Ccrk mutants show dramatic patterning defects, with an expansion of the optic stalk domain into the optic cup, as well as an expansion of the retinal pigment epithelium (RPE) into neural retina (NR) territory. In addition, Ccrk mutants display a shortened optic stalk. These defects are associated with bimodal changes in Hedgehog (Hh) pathway activity within the eye, including the loss of proximal, high level responses but a gain in distal, low level responses. We simultaneously removed the Hh activator GLI2 in Ccrk mutants (Ccrk-/-;Gli2-/-), which resulted in rescue of optic cup patterning and exacerbation of optic stalk length defects. Next, we disrupted the Hh pathway antagonist GLI3 in mutants lacking CCRK (Ccrk-/-;Gli3-/-), which lead to even greater expansion of the RPE markers into the NR domain and a complete loss of NR specification within the optic cup. These results indicate that CCRK functions in eye development by both positively and negatively regulating the Hh pathway, and they reveal distinct requirements for Hh signaling in patterning and morphogenesis of the eyes.
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Affiliation(s)
- Floria I Lupu
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Jacob B Burnett
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
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215
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The primary cilium is necessary for the differentiation and the maintenance of human adipose progenitors into myofibroblasts. Sci Rep 2017; 7:15248. [PMID: 29127365 PMCID: PMC5681559 DOI: 10.1038/s41598-017-15649-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 10/31/2017] [Indexed: 02/06/2023] Open
Abstract
The primary cilium is an organelle, present at the cell surface, with various biological functions. We, and others, have shown that it plays a role in the differentiation of adipose progenitors (APs) into adipocytes. APs can also differentiate into myofibroblasts when treated with TGF-β1. Several components of the TGF-β1 pathway are located within the cilium suggesting a function for this organelle in AP myofibrogenesis. We studied differentiation of APs into myofibroblasts in two human models: APs of the adipose tissue (aAPs) and APs resident in the skeletal muscles (mAPs). We showed that, in vivo, myofibroblasts within muscles of patients with Duchenne Muscular Dystrophy were ciliated. In vitro, myofibroblasts derived from APs maintained a functional primary cilium. Using HPI4, a small molecule that inhibits ciliogenesis, and siRNA against Kif-3A, we provide evidence that the primary cilium is necessary both for the differentiation of APs into myofibroblasts and the maintenance of the phenotype. Disruption of the primary cilium inhibited TGF-β1-signalisation providing a molecular mechanism by which the cilium controls myofibroblast differentiation. These data suggest that myofibroblasts from various origins are controlled differently by their primary cilium.
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216
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Bernabé-Rubio M, Alonso MA. Routes and machinery of primary cilium biogenesis. Cell Mol Life Sci 2017; 74:4077-4095. [PMID: 28624967 PMCID: PMC11107551 DOI: 10.1007/s00018-017-2570-5] [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: 04/24/2017] [Revised: 06/01/2017] [Accepted: 06/13/2017] [Indexed: 02/06/2023]
Abstract
Primary cilia are solitary, microtubule-based protrusions of the cell surface that play fundamental roles as photosensors, mechanosensors and biochemical sensors. Primary cilia dysfunction results in a long list of developmental and degenerative disorders that combine to give rise to a large spectrum of human diseases affecting almost any major body organ. Depending on the cell type, primary ciliogenesis is initiated intracellularly, as in fibroblasts, or at the cell surface, as in renal polarized epithelial cells. In this review, we have focused on the routes of primary ciliogenesis placing particular emphasis on the recently described pathway in renal polarized epithelial cells by which the midbody remnant resulting from a previous cell division event enables the centrosome for initiation of primary cilium assembly. The protein machinery implicated in primary cilium formation in epithelial cells, including the machinery best known for its involvement in establishing cell polarity and polarized membrane trafficking, is also discussed.
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Affiliation(s)
- Miguel Bernabé-Rubio
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Nicolás Cabrera 1, Cantoblanco, 28049, Madrid, Spain
| | - Miguel A Alonso
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Nicolás Cabrera 1, Cantoblanco, 28049, Madrid, Spain.
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217
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Schmitz F, Burtscher I, Stauber M, Gossler A, Lickert H. A novel Cre-inducible knock-in ARL13B-tRFP fusion cilium reporter. Genesis 2017; 55. [PMID: 28948682 DOI: 10.1002/dvg.23073] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 09/14/2017] [Accepted: 09/20/2017] [Indexed: 12/29/2022]
Abstract
Cilia play a major role in the regulation of numerous signaling pathways and are essential for embryonic development. Mutations in genes affecting ciliary function can cause a variety of diseases in humans summarized as ciliopathies. To facilitate the detection and visualization of cilia in a temporal and spatial manner in mouse tissues, we generated a Cre-inducible cilium-specific reporter mouse line expressing an ARL13B-tRFP fusion protein driven by a CMV enhancer/chicken β actin promotor (pCAG) from the Hprt locus. We detected bright and specific ciliary signals by immunostainings of various mono- and multiciliated tissues and by time-lapse live-cell analysis of cultured embryos and organ explant cultures. Additionally, we monitored cilium assembly and disassembly in embryonic fibroblast cells using live-cell imaging. Thus, the ARL13B-tRFP reporter mouse strain is a valuable tool for the investigation of ciliary structure and function in a tissue-specific manner to understand processes, such as ciliary protein trafficking or cilium-dependent signaling in vitro and in vivo.
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Affiliation(s)
- Felizitas Schmitz
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Business Campus Garching, Parkring 11, Garching, D-85748, Germany
- Institute of Stem Cell Research, Helmholtz Zentrum München, Ingolstädter Landstraße 1, Neuherberg, D-85764, Germany
| | - Ingo Burtscher
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Business Campus Garching, Parkring 11, Garching, D-85748, Germany
- Institute of Stem Cell Research, Helmholtz Zentrum München, Ingolstädter Landstraße 1, Neuherberg, D-85764, Germany
| | - Michael Stauber
- Institute of Molecular Biology OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, Hannover, 30625, Germany
| | - Achim Gossler
- Institute of Molecular Biology OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str.1, Hannover, 30625, Germany
| | - Heiko Lickert
- Institute of Diabetes and Regeneration Research, Helmholtz Zentrum München, Business Campus Garching, Parkring 11, Garching, D-85748, Germany
- Institute of Stem Cell Research, Helmholtz Zentrum München, Ingolstädter Landstraße 1, Neuherberg, D-85764, Germany
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218
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Spasic M, Jacobs CR. Primary cilia: Cell and molecular mechanosensors directing whole tissue function. Semin Cell Dev Biol 2017; 71:42-52. [PMID: 28843978 PMCID: PMC5922257 DOI: 10.1016/j.semcdb.2017.08.036] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/15/2017] [Accepted: 08/18/2017] [Indexed: 01/09/2023]
Abstract
Primary cilia are immotile, microtubule-based organelles extending from the surface of nearly every mammalian cell. Mechanical stimulation causes deflection of the primary cilium, initiating downstream signaling cascades to the rest of the cell. The cilium forms a unique subcellular microdomain, and defects in ciliary protein composition or physical structure have been associated with a myriad of human pathologies. In this review, we discuss the importance of ciliary mechanotransduction at the cell and tissue level, and how furthering our molecular understanding of primary cilia mechanobiology may lead to therapeutic strategies to treat human diseases.
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Affiliation(s)
- Milos Spasic
- Columbia University, Department of Biomedical Engineering, United States.
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219
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Hanke-Gogokhia C, Wu Z, Sharif A, Yazigi H, Frederick JM, Baehr W. The guanine nucleotide exchange factor Arf-like protein 13b is essential for assembly of the mouse photoreceptor transition zone and outer segment. J Biol Chem 2017; 292:21442-21456. [PMID: 29089384 DOI: 10.1074/jbc.ra117.000141] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 10/24/2017] [Indexed: 01/17/2023] Open
Abstract
Arf-like protein 13b (ARL13b) is a small GTPase that functions as a guanosine nucleotide exchange factor (GEF) for ARL3-GDP. ARL13b is located exclusively in photoreceptor outer segments (OS) presumably anchored to discs by palmitoylation, whereas ARL3 is an inner segment cytoplasmic protein. Hypomorphic mutations affecting the ARL13b G-domain inactivate GEF activity and lead to Joubert syndrome (JS) in humans. However, the molecular mechanisms in ARL13b mutation-induced Joubert syndrome, particularly the function of primary cilia, are still incompletely understood. Because Arl13b germline knockouts in mouse are lethal, we generated retina-specific deletions of ARL13b in which ARL3-GTP formation is impaired. In mouse retArl13b-/- central retina at postnatal day 6 (P6) and older, outer segments were absent, thereby preventing trafficking of outer segment proteins to their destination. Ultrastructure of postnatal day 10 (P10) central retArl13b-/- photoreceptors revealed docking of basal bodies to cell membranes, but mature transition zones and disc structures were absent. Deletion of ARL13b in adult mice via tamoxifen-induced Cre/loxP recombination indicated that axonemes gradually shorten and outer segments progressively degenerate. IFT88, essential for anterograde intraflagellar transport (IFT), was significantly reduced at tamArl13b-/- basal bodies, suggesting impairment of intraflagellar transport. AAV2/8 vector-mediated ARL13b expression in the retArl13b-/- retina rescued ciliogenesis.
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Affiliation(s)
- Christin Hanke-Gogokhia
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Zhijian Wu
- NEI, National Institutes of Health, Bethesda, Maryland 20892
| | - Ali Sharif
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Hussein Yazigi
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Jeanne M Frederick
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132
| | - Wolfgang Baehr
- From the Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah 84132, .,Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, Utah 84132, and.,Department of Biology, University of Utah, Salt Lake City, Utah 84112
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220
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Wu C, Li J, Peterson A, Tao K, Wang B. Loss of dynein-2 intermediate chain Wdr34 results in defects in retrograde ciliary protein trafficking and Hedgehog signaling in the mouse. Hum Mol Genet 2017; 26:2386-2397. [PMID: 28379358 DOI: 10.1093/hmg/ddx127] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/28/2017] [Indexed: 11/14/2022] Open
Abstract
The Wdr34 gene encodes an intermediate chain of cytoplasmic dynein 2, the motor for retrograde intraflagellar transport (IFT) in primary cilia. Although mutations in human WDR34 have recently been reported, the association of WDR34 function with Hedgehog (Hh) signaling has not been established, and actual cilia defects in the WDR34 mutant cells have also not been completely characterized. In the present study, we show that Wdr34 mutant mice die in midgestation and exhibit open brain and polydactyly phenotypes. Several Hh-dependent ventral neural cell types are not specified in the mutant neural tube. The expression of the direct Hh targets, Gli1 and Patched 1, is inhibited, while the expression of limb patterning genes that are normally inhibited by the Gli3 repressor is anteriorly expanded in mutant limbs. Comparison of cilia phenotype and function among wild type, Dnchc2 (dynein 2 heavy chain), and Wdr34 mutant cells demonstrates that cilia in both Dnchc2 and Wdr34 mutant cells are stumpy. Several ciliary proteins examined abnormally accumulate in the cilia of both mutant cells. Consistent with its function, overexpressed Wdr34 is occasionally localized to cilia, and Wdr34 is required for the ciliary localization of dynein 2 light intermediate chain Lic3. More interestingly, we show that both Dnchc2 and Wdr34 act between Smo and Gli2/Gli3 in the Hh pathway. Therefore, like Dnchc2, Wdr34 is required for ciliogenesis, retrograde ciliary protein trafficking, and the regulation of Gli2/Gli3 activators and repressors. Furthermore, both Wdr34 and Dnchc2 promote microtubule growth, a novel dynein 2 function in a non-cilia structure.
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Affiliation(s)
- Chuanqing Wu
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.,Department of Genetic Medicine, Weill Medical College of Cornell University, W404, New York, NY 10065,USA
| | - Jia Li
- Department of Genetic Medicine, Weill Medical College of Cornell University, W404, New York, NY 10065,USA.,Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China
| | - Andrew Peterson
- Department of Molecular Biology, Genentech, South San Francisco, CA 94080, USA
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Baolin Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, W404, New York, NY 10065,USA.,Department of Cell and Developmental Biology, Weill Medical College of Cornell University, W404, New York, NY 10065, USA
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221
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Roy K, Jerman S, Jozsef L, McNamara T, Onyekaba G, Sun Z, Marin EP. Palmitoylation of the ciliary GTPase ARL13b is necessary for its stability and its role in cilia formation. J Biol Chem 2017; 292:17703-17717. [PMID: 28848045 PMCID: PMC5663873 DOI: 10.1074/jbc.m117.792937] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 08/18/2017] [Indexed: 01/01/2023] Open
Abstract
Primary cilia are hairlike extensions of the plasma membrane of most mammalian cells that serve specialized signaling functions. To traffic properly to cilia, multiple cilia proteins rely on palmitoylation, the post-translational attachment of a saturated 16-carbon lipid. However, details regarding the mechanism of how palmitoylation affects cilia protein localization and function are unknown. Herein, we investigated the protein ADP-ribosylation factor-like GTPase 13b (ARL13b) as a model palmitoylated ciliary protein. Using biochemical, cellular, and in vivo studies, we found that ARL13b palmitoylation occurs in vivo in mouse kidneys and that it is required for trafficking to and function within cilia. Myristoylation, a 14-carbon lipid, is shown to largely substitute for palmitoylation with regard to cilia localization of ARL13b, but not with regard to its function within cilia. The functional importance of palmitoylation results in part from a dramatic increase in ARL13b stability, which is not observed with myristoylation. Additional results show that blockade of depalmitoylation slows the degradation of ARL13b that occurs during cilia resorption, raising the possibility that the sensitivity of ARL13b stability to palmitoylation may be exploited by the cell to accelerate degradation of ARL13b by depalmitoylating it. Together, the results show that palmitoylation plays a unique and critical role in controlling the localization, stability, abundance, and thus function of ARL13b. Pharmacological manipulation of protein palmitoylation may be a strategy to alter cilia function.
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Affiliation(s)
- Kasturi Roy
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Stephanie Jerman
- the Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Levente Jozsef
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Thomas McNamara
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Ginikanwa Onyekaba
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
| | - Zhaoxia Sun
- the Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520-8029
| | - Ethan P Marin
- From the Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine, New Haven, Connecticut 06520-8029 and
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222
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Iulianella A, Sakai D, Kurosaka H, Trainor PA. Ventral neural patterning in the absence of a Shh activity gradient from the floorplate. Dev Dyn 2017; 247:170-184. [PMID: 28891097 DOI: 10.1002/dvdy.24590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/09/2017] [Accepted: 09/07/2017] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Vertebrate spinal cord development requires Sonic Hedgehog (Shh) signaling from the floorplate and notochord, where it is thought to act in concentration dependent manner to pattern distinct cell identities along the ventral-to-dorsal axis. While in vitro experiments demonstrate naïve neural tissues are sensitive to small changes in Shh levels, genetic studies illustrate that some degree of ventral patterning can occur despite significant perturbations in Shh signaling. Consequently, the mechanistic relationship between Shh morphogen levels and acquisition of distinct cell identities remains unclear. RESULTS We addressed this using Hedgehog acetyltransferase (HhatCreface ) and Wiggable mouse mutants. Hhat encodes a palmitoylase required for the secretion of Hedgehog proteins and formation of the Shh gradient. In its absence, the spinal cord develops without floorplate cells and V3 interneurons. Wiggable is an allele of the Shh receptor Patched1 (Ptch1Wig ) that is unable to inhibit Shh signal transduction, resulting in expanded ventral progenitor domains. Surprisingly, HhatCreface/Creface ; Ptch1Wig/Wig double mutants displayed fully restored ventral patterning despite an absence of Shh secretion from the floorplate. CONCLUSIONS The full range of neuronal progenitor types can be generated in the absence of a Shh gradient provided pathway repression is dampened, illustrating the complexity of morphogen dynamics in vertebrate patterning. Developmental Dynamics 247:170-184, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Angelo Iulianella
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, and Brain Repair Centre, Life Sciences Research Institute, Halifax, Nova Scotia, Canada
| | - Daisuke Sakai
- Doshisha University, Graduate School of Brain Science, Kyotanabe, Kyoto, Japan
| | - Hiroshi Kurosaka
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Paul A Trainor
- Stowers Institute For Medical Research, Kansas City, Missouri.,Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas
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223
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Agbu SO, Liang Y, Liu A, Anderson KV. The small GTPase RSG1 controls a final step in primary cilia initiation. J Cell Biol 2017; 217:413-427. [PMID: 29038301 PMCID: PMC5748968 DOI: 10.1083/jcb.201604048] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 08/18/2016] [Accepted: 09/21/2017] [Indexed: 12/11/2022] Open
Abstract
Primary cilia are essential for normal development and tissue homeostasis, but the mechanisms that remodel the centriole to promote cilia initiation are not well understood. Agbu et al. report that mouse RSG1, a small GTPase, regulates a late step in cilia initiation, downstream of TTBK2 and the CPLANE protein INTU. Primary cilia, which are essential for normal development and tissue homeostasis, are extensions of the mother centriole, but the mechanisms that remodel the centriole to promote cilia initiation are poorly understood. Here we show that mouse embryos that lack the small guanosine triphosphatase RSG1 die at embryonic day 12.5, with developmental abnormalities characteristic of decreased cilia-dependent Hedgehog signaling. Rsg1 mutant embryos have fewer primary cilia than wild-type embryos, but the cilia that form are of normal length and traffic Hedgehog pathway proteins within the cilium correctly. Rsg1 mother centrioles recruit proteins required for cilia initiation and dock onto ciliary vesicles, but axonemal microtubules fail to elongate normally. RSG1 localizes to the mother centriole in a process that depends on tau tubulin kinase 2 (TTBK2), the CPLANE complex protein Inturned (INTU), and its own GTPase activity. The data suggest a specific role for RSG1 in the final maturation of the mother centriole and ciliary vesicle that allows extension of the ciliary axoneme.
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Affiliation(s)
- Stephanie O Agbu
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Biochemistry, Cell and Molecular Biology Program, Weill Graduate School of Medical Sciences of Cornell University, New York, NY
| | - Yinwen Liang
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Aimin Liu
- Department of Biology, Eberly College of Science, The Pennsylvania State University, University Park, PA
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
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224
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Shinohara K, Hamada H. Cilia in Left-Right Symmetry Breaking. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a028282. [PMID: 28213464 DOI: 10.1101/cshperspect.a028282] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Visceral organs of vertebrates show left-right (L-R) asymmetry with regard to their position and morphology. Cilia play essential role in generating L-R asymmetry. A number of genes required for L-R asymmetry have now been identified in vertebrates, including human, many of which contribute to the formation and motility of cilia. In the mouse embryo, breaking of L-R symmetry occurs in the ventral node, where two types of cilia (motile and immotile) are present. Motile cilia are located at the central region of the node, and generate a leftward fluid flow. These motile cilia at the node are unique in that they rotate in the clockwise direction, unlike other immotile cilia such as airway cilia that show planar beating. The second type of cilia essential for L-R asymmetry is immotile cilia that are peripherally located immotile cilia. They sense a flow-dependent signal, which is either chemical or mechanical in nature. Although Ca2+ signaling is implicated in flow sensing, the precise mechanism remains unknown.
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Affiliation(s)
- Kyosuke Shinohara
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo 184-8588, Japan
| | - Hiroshi Hamada
- Developmental Genetics Group, Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan
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225
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Guo J, Otis JM, Higginbotham H, Monckton C, Cheng J, Asokan A, Mykytyn K, Caspary T, Stuber GD, Anton ES. Primary Cilia Signaling Shapes the Development of Interneuronal Connectivity. Dev Cell 2017; 42:286-300.e4. [PMID: 28787594 DOI: 10.1016/j.devcel.2017.07.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 05/18/2017] [Accepted: 07/12/2017] [Indexed: 01/06/2023]
Abstract
Appropriate growth and synaptic integration of GABAergic inhibitory interneurons are essential for functional neural circuits in the brain. Here, we demonstrate that disruption of primary cilia function following the selective loss of ciliary GTPase Arl13b in interneurons impairs interneuronal morphology and synaptic connectivity, leading to altered excitatory/inhibitory activity balance. The altered morphology and connectivity of cilia mutant interneurons and the functional deficits are rescued by either chemogenetic activation of ciliary G-protein-coupled receptor (GPCR) signaling or the selective induction of Sstr3, a ciliary GPCR, in Arl13b-deficient cilia. Our results thus define a specific requirement for primary cilia-mediated GPCR signaling in interneuronal connectivity and inhibitory circuit formation.
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Affiliation(s)
- Jiami Guo
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - James M Otis
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Holden Higginbotham
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Chase Monckton
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - JrGang Cheng
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Aravind Asokan
- Department of Genetics and Gene Therapy Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Kirk Mykytyn
- Department of Biological Chemistry and Pharmacology, Neuroscience Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Garret D Stuber
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - E S Anton
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA.
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226
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Schock EN, Brugmann SA. Neural crest cells utilize primary cilia to regulate ventral forebrain morphogenesis via Hedgehog-dependent regulation of oriented cell division. Dev Biol 2017; 431:168-178. [PMID: 28941984 DOI: 10.1016/j.ydbio.2017.09.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 08/20/2017] [Accepted: 09/19/2017] [Indexed: 12/18/2022]
Abstract
Development of the brain directly influences the development of the face via both physical growth and Sonic hedgehog (SHH) activity; however, little is known about how neural crest cells (NCCs), the mesenchymal population that comprise the developing facial prominences, influence the development of the brain. We utilized the conditional ciliary mutant Wnt1-Cre;Kif3afl/fl to demonstrate that loss of primary cilia on NCCs resulted in a widened ventral forebrain. We found that neuroectodermal Shh expression, dorsal/ventral patterning, and amount of proliferation in the ventral neuroectoderm was not changed in Wnt1-Cre;Kif3afl/fl mutants; however, tissue polarity and directional cell division were disrupted. Furthermore, NCCs of Wnt1-Cre;Kif3afl/fl mutants failed to respond to a SHH signal emanating from the ventral forebrain. We were able to recapitulate the ventral forebrain phenotype by removing Smoothened from NCCs (Wnt1-Cre;Smofl/fl) indicating that changes in the ventral forebrain were mediated through a Hedgehog-dependent mechanism. Together, these data suggest a novel, cilia-dependent mechanism for NCCs during forebrain development.
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Affiliation(s)
- Elizabeth N Schock
- Division of Plastic Surgery, Department of Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Samantha A Brugmann
- Division of Plastic Surgery, Department of Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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227
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Mukhopadhyay S, Badgandi HB, Hwang SH, Somatilaka B, Shimada IS, Pal K. Trafficking to the primary cilium membrane. Mol Biol Cell 2017; 28:233-239. [PMID: 28082521 PMCID: PMC5231892 DOI: 10.1091/mbc.e16-07-0505] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/14/2016] [Accepted: 11/15/2016] [Indexed: 12/13/2022] Open
Abstract
The primary cilium has been found to be associated with a number of cellular signaling pathways, such as vertebrate hedgehog signaling, and implicated in the pathogenesis of diseases affecting multiple organs, including the neural tube, kidney, and brain. The primary cilium is the site where a subset of the cell's membrane proteins is enriched. However, pathways that target and concentrate membrane proteins in cilia are not well understood. Processes determining the level of proteins in the ciliary membrane include entry into the compartment, removal, and retention by diffusion barriers such as the transition zone. Proteins that are concentrated in the ciliary membrane are also localized to other cellular sites. Thus it is critical to determine the particular role for ciliary compartmentalization in sensory reception and signaling pathways. Here we provide a brief overview of our current understanding of compartmentalization of proteins in the ciliary membrane and the dynamics of trafficking into and out of the cilium. We also discuss major unanswered questions regarding the role that defects in ciliary compartmentalization might play in disease pathogenesis. Understanding the trafficking mechanisms that underlie the role of ciliary compartmentalization in signaling might provide unique approaches for intervention in progressive ciliopathies.
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Affiliation(s)
- Saikat Mukhopadhyay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Hemant B Badgandi
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Sun-Hee Hwang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | | | - Issei S Shimada
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Kasturi Pal
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
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228
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Mitchison HM, Shoemark A. Motile cilia defects in diseases other than primary ciliary dyskinesia: The contemporary diagnostic and research role for transmission electron microscopy. Ultrastruct Pathol 2017; 41:415-427. [PMID: 28925789 DOI: 10.1080/01913123.2017.1370050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ultrastructural studies have underpinned the cell biological and clinical investigations of the varied roles of motile cilia in health and disease, with a long history since the 1950s. Recent developments from transmission electron microscopy (TEM; cryo-electron microscopy, electron tomography) have yielded higher resolution and fresh insights into the structure and function of these complex organelles. Microscopy in ciliated organisms, disease models, and in patients with ciliopathy diseases has dramatically expanded our understanding of the ubiquity, multisystem involvement, and importance of cilia in normal human development. Here, we review the importance of motile cilia ultrastructural studies in understanding the basis of diseases other than primary ciliary dyskinesia.
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Affiliation(s)
- Hannah M Mitchison
- a Newlife Birth Defects Research Centre, Experimental and Personalised Medicine, Genetics and Genomic Medicine Programme, UCL Great Ormond Street Institute of Child Health , University College London , London , UK
| | - Amelia Shoemark
- b Department of Paediatric Respiratory Medicine , Royal Brompton & Harefield NHS Trust , London , UK.,c Division of Molecular & Clinical Medicine, School of Medicine , Ninewells Hospital and Medical School , Dundee , UK
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229
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Thorpe SD, Gambassi S, Thompson CL, Chandrakumar C, Santucci A, Knight MM. Reduced primary cilia length and altered Arl13b expression are associated with deregulated chondrocyte Hedgehog signaling in alkaptonuria. J Cell Physiol 2017; 232:2407-2417. [PMID: 28158906 PMCID: PMC5484994 DOI: 10.1002/jcp.25839] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/11/2017] [Accepted: 02/02/2017] [Indexed: 12/14/2022]
Abstract
Alkaptonuria (AKU) is a rare inherited disease resulting from a deficiency of the enzyme homogentisate 1,2-dioxygenase which leads to the accumulation of homogentisic acid (HGA). AKU is characterized by severe cartilage degeneration, similar to that observed in osteoarthritis. Previous studies suggest that AKU is associated with alterations in cytoskeletal organization which could modulate primary cilia structure/function. This study investigated whether AKU is associated with changes in chondrocyte primary cilia and associated Hedgehog signaling which mediates cartilage degradation in osteoarthritis. Human articular chondrocytes were obtained from healthy and AKU donors. Additionally, healthy chondrocytes were treated with HGA to replicate AKU pathology (+HGA). Diseased cells exhibited shorter cilia with length reductions of 36% and 16% in AKU and +HGA chondrocytes respectively, when compared to healthy controls. Both AKU and +HGA chondrocytes demonstrated disruption of the usual cilia length regulation by actin contractility. Furthermore, the proportion of cilia with axoneme breaks and bulbous tips was increased in AKU chondrocytes consistent with defective regulation of ciliary trafficking. Distribution of the Hedgehog-related protein Arl13b along the ciliary axoneme was altered such that its localization was increased at the distal tip in AKU and +HGA chondrocytes. These changes in cilia structure/trafficking in AKU and +HGA chondrocytes were associated with a complete inability to activate Hedgehog signaling in response to exogenous ligand. Thus, we suggest that altered responsiveness to Hedgehog, as a consequence of cilia dysfunction, may be a contributing factor in the development of arthropathy highlighting the cilium as a novel target in AKU.
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Affiliation(s)
- Stephen D. Thorpe
- Institute of BioengineeringSchool of Engineering and Materials ScienceQueen Mary University of LondonLondonUnited Kingdom
| | - Silvia Gambassi
- Dipartimento di BiotecnologieChimica e FarmaciaUniversità degli Studi di SienaSienaItaly
| | - Clare L. Thompson
- Institute of BioengineeringSchool of Engineering and Materials ScienceQueen Mary University of LondonLondonUnited Kingdom
| | - Charmilie Chandrakumar
- Institute of BioengineeringSchool of Engineering and Materials ScienceQueen Mary University of LondonLondonUnited Kingdom
| | - Annalisa Santucci
- Dipartimento di BiotecnologieChimica e FarmaciaUniversità degli Studi di SienaSienaItaly
| | - Martin M. Knight
- Institute of BioengineeringSchool of Engineering and Materials ScienceQueen Mary University of LondonLondonUnited Kingdom
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230
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Cell Cycle-Related Kinase (CCRK) regulates ciliogenesis and Hedgehog signaling in mice. PLoS Genet 2017; 13:e1006912. [PMID: 28817564 PMCID: PMC5574612 DOI: 10.1371/journal.pgen.1006912] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 08/29/2017] [Accepted: 07/06/2017] [Indexed: 01/04/2023] Open
Abstract
The Hedgehog (Hh) signaling pathway plays a key role in cell fate specification, proliferation, and survival during mammalian development. Cells require a small organelle, the primary cilium, to respond properly to Hh signals and the key regulators of Hh signal transduction exhibit dynamic localization to this organelle when the pathway is activated. Here, we investigate the role of Cell Cycle Related kinase (CCRK) in regulation of cilium-dependent Hh signaling in the mouse. Mice mutant for Ccrk exhibit a variety of developmental defects indicative of inappropriate regulation of this pathway. Cell biological, biochemical and genetic analyses indicate that CCRK is required to control the Hedgehog pathway at the level or downstream of Smoothened and upstream of the Gli transcription factors, Gli2 and Gli3. In vitro experiments indicate that Ccrk mutant cells show a greater deficit in response to signaling over long time periods than over short ones. Similar to Chlamydomonas mutants lacking the CCRK homolog, LF2, mouse Ccrk mutant cells show defective regulation of ciliary length and morphology. Ccrk mutant cells exhibit defects in intraflagellar transport (the transport mechanism used to assemble cilia), as well as slowed kinetics of ciliary enrichment of key Hh pathway regulators. Collectively, the data suggest that CCRK positively regulates the kinetics by which ciliary proteins such as Smoothened and Gli2 are imported into the cilium, and that the efficiency of ciliary recruitment allows for potent responses to Hedgehog signaling over long time periods. The importance of cilia in development and disease has become broadly appreciated in recent years due in part to their roles in signal transduction. Despite this attention, crucial aspects of ciliary assembly and function, such as the mechanisms controlling ciliary assembly and the signal transduction events occurring in cilia, remain unclear. Cilia play a central role in sensing and transducing Hedgehog signals in the context of mammalian embryogenesis and in a variety of cancers. Here, we investigate the functions of Cell Cycle Related Kinase (CCRK), which plays an evolutionarily conserved function in the assembly of cilia and flagella. We find that mouse CCRK positively and negatively regulates ciliary length. We show that CCRK controls multiple aspects of Hedgehog signaling in vivo and in vitro by regulating the processing and activities of the Gli transcription factors. Our data suggest that CCRK controls Hedgehog signaling by promoting the efficient ciliary import of core signaling components.
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231
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Wang C, Li J, Meng Q, Wang B. Three Tctn proteins are functionally conserved in the regulation of neural tube patterning and Gli3 processing but not ciliogenesis and Hedgehog signaling in the mouse. Dev Biol 2017; 430:156-165. [PMID: 28800946 DOI: 10.1016/j.ydbio.2017.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 08/02/2017] [Accepted: 08/02/2017] [Indexed: 01/10/2023]
Abstract
Tctn1, Tctn2, and Tctn3 are membrane proteins that localize at the transition zone of primary cilia. Tctn1 and Tctn2 mutations have been reported in both humans and mice, but Tctn3 mutations have been reported only in humans. It is also not clear whether the three Tctn proteins are functionally conserved with respect to ciliogenesis and Hedgehog (Hh) signaling. In the present study, we report that loss of Tctn3 gene function in mice results in a decrease in ciliogenesis and Hh signaling. Consistent with this, Tctn3 mutant mice exhibit holoprosencephaly and randomized heart looping and lack the floor plate in the neural tube, the phenotypes similar to those of Tctn1 and Tctn2 mutants. We also show that overexpression of Tctn3, but not Tctn1 or Tctn2, can rescue ciliogenesis in Tctn3 mutant cells. Similarly, replacement of Tctn3 with Tctn1 or Tctn2 in the Tctn3 gene locus results in reduced ciliogenesis and Hh signaling, holoprosencephaly, and randomized heart looping. Surprisingly, however, the neural tube patterning and the proteolytic processing of Gli3 (a transcription regulator for Hh signaling) into a repressor, both of which are usually impaired in ciliary gene mutants, are normal. These results suggest that Tctn1, Tctn2, and Tctn3 are functionally divergent with respect to their role in ciliogenesis and Hh signaling but conserved in neural tube patterning and Gli3 processing.
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Affiliation(s)
- Chengbing Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Jia Li
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Qing Meng
- Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China.
| | - Baolin Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA; Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA.
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232
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Burnett JB, Lupu FI, Eggenschwiler JT. Proper ciliary assembly is critical for restricting Hedgehog signaling during early eye development in mice. Dev Biol 2017; 430:32-40. [PMID: 28778798 DOI: 10.1016/j.ydbio.2017.07.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/20/2017] [Accepted: 07/20/2017] [Indexed: 11/25/2022]
Abstract
Patterning of the vertebrate eye into optic stalk, retinal pigment epithelium (RPE) and neural retina (NR) territories relies on a number of signaling pathways, but how these signals are interpreted by optic progenitors is not well understood. The primary cilium is a microtubule-based organelle that is essential for Hedgehog (Hh) signaling, but it has also been implicated in the regulation of other signaling pathways. Here, we show that the optic primordium is ciliated during early eye development and that ciliogenesis is essential for proper patterning and morphogenesis of the mouse eye. Ift172 mutants fail to generate primary cilia and exhibit patterning defects that resemble those of Gli3 mutants, suggesting that cilia are required to restrict Hh activity during eye formation. Ift122 mutants, which produce cilia with abnormal morphology, generate optic vesicles that fail to invaginate to produce the optic cup. These mutants also lack formation of the lens, RPE and NR. Such phenotypic features are accompanied by strong, ectopic Hh pathway activity, evidenced by altered gene expression patterns. Removal of GLI2 from Ift122 mutants rescued several aspects of optic cup and lens morphogenesis as well as RPE and NR specification. Collectively, our data suggest that proper assembly of primary cilia is critical for restricting the Hedgehog pathway during eye formation in the mouse.
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Affiliation(s)
- Jacob B Burnett
- Department of Genetics, University of Georgia, Athens, GA 30602, United States
| | - Floria I Lupu
- Department of Genetics, University of Georgia, Athens, GA 30602, United States
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233
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Shao J, Xu L, Chen L, Lu Q, Xie X, Shi W, Xiong H, Shi C, Huang X, Mei J, Rao H, Lu H, Lu N, Luo S. Arl13b Promotes Gastric Tumorigenesis by Regulating Smo Trafficking and Activation of the Hedgehog Signaling Pathway. Cancer Res 2017; 77:4000-4013. [PMID: 28611043 PMCID: PMC5540784 DOI: 10.1158/0008-5472.can-16-2461] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 03/21/2017] [Accepted: 06/05/2017] [Indexed: 12/23/2022]
Abstract
Inhibitors of the Hedgehog (Hh) pathway transducer Smoothened (Smo) have been approved for cancer treatment, but Smo mutations often lead to tumor resistance and it remains unclear how Smo is regulated. In this study, we identified the small GTPase Arl13b as a novel partner and regulator of Smo. Arl13b regulated Smo stability, trafficking, and localization, which are each crucial for Hh signaling. In gastric cancer cells, Arl13b stimulated proliferation, migration, and invasion in vitro and in vivo In clinical specimens of gastric cancer, Arl13b expression correlated strongly with tumor size and depth of invasion; patients with high levels of Arl13b had a poor prognosis. Our results show how Arl13b participates in Hh pathway activation in gastric cancer. Cancer Res; 77(15); 4000-13. ©2017 AACR.
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Affiliation(s)
- Jia Shao
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Linlin Xu
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Limin Chen
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Quqin Lu
- Department of Epidemiology & Biostatistics, School of Public Health, Nanchang University, Nanchang, Jiangxi, China
| | - Xinsheng Xie
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Wei Shi
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Huanting Xiong
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Chao Shi
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Xuan Huang
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Jinhong Mei
- Department of Pathology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Hai Rao
- Department of Molecular Medicine, University of Texas Health, San Antonio, Texas
| | - Hua Lu
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, Louisiana
| | - Nonghua Lu
- Institute of Digestive Disease, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Shiwen Luo
- Center for Experimental Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
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234
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Li J, Wang C, Wu C, Cao T, Xu G, Meng Q, Wang B. PKA-mediated Gli2 and Gli3 phosphorylation is inhibited by Hedgehog signaling in cilia and reduced in Talpid3 mutant. Dev Biol 2017; 429:147-157. [PMID: 28673820 DOI: 10.1016/j.ydbio.2017.06.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 10/19/2022]
Abstract
Hedgehog (Hh) signaling is thought to occur in primary cilia, but the molecular basis of Gli2 and Gli3 activation by Hh signaling in cilia is unknown. Similarly, how ciliary gene mutations result in reduced Gli3 processing that generates a repressor is also not clear. Here we show that Hh signaling inhibits Gli2 and Gli3 phosphorylation by protein kinase A (PKA) in cilia. The cilia related gene Talpid3 (Ta3) mutation results in the reduced processing and phosphorylation of Gli2 and Gli3. Interestingly, Ta3 interacts and colocalizes with PKA regulatory subunit PKARIIβ at centrioles in the cell. The centriolar localization and PKA binding regions are located in the N- and C-terminal regions of Ta3, respectively. PKARIIβ fails to localize at centrioles in some Ta3 mutant cells. Therefore, our study provides the direct evidence that Gli2 and Gli3 are dephosphorylated and activated in cilia and that impaired Gli2 and Gli3 processing in Ta3 mutant is at least in part due to a decrease in Gli2 and Gli3 phosphorylation.
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Affiliation(s)
- Jia Li
- Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China; Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Chengbing Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA
| | - Chuanqing Wu
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA; Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Ting Cao
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA; College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Guoqiang Xu
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and College of Pharmaceutical Sciences, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, Jiangsu, China
| | - Qing Meng
- Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China.
| | - Baolin Wang
- Department of Genetic Medicine, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA; Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, W404, New York, NY 10065, USA.
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235
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Schwarz N, Lane A, Jovanovic K, Parfitt DA, Aguila M, Thompson CL, da Cruz L, Coffey PJ, Chapple JP, Hardcastle AJ, Cheetham ME. Arl3 and RP2 regulate the trafficking of ciliary tip kinesins. Hum Mol Genet 2017; 26:2480-2492. [PMID: 28444310 PMCID: PMC5808637 DOI: 10.1093/hmg/ddx143] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/07/2017] [Accepted: 04/11/2017] [Indexed: 11/14/2022] Open
Abstract
Ciliary trafficking defects are the underlying cause of many ciliopathies, including Retinitis Pigmentosa (RP). Anterograde intraflagellar transport (IFT) is mediated by kinesin motor proteins; however, the function of the homodimeric Kif17 motor in cilia is poorly understood, whereas Kif7 is known to play an important role in stabilizing cilia tips. Here we identified the ciliary tip kinesins Kif7 and Kif17 as novel interaction partners of the small GTPase Arl3 and its regulatory GTPase activating protein (GAP) Retinitis Pigmentosa 2 (RP2). We show that Arl3 and RP2 mediate the localization of GFP-Kif17 to the cilia tip and competitive binding of RP2 and Arl3 with Kif17 complexes. RP2 and Arl3 also interact with another ciliary tip kinesin, Kif7, which is a conserved regulator of Hedgehog (Hh) signaling. siRNA-mediated loss of RP2 or Arl3 reduced the level of Kif7 at the cilia tip. This was further validated by reduced levels of Kif7 at cilia tips detected in fibroblasts and induced pluripotent stem cell (iPSC) 3D optic cups derived from a patient carrying an RP2 nonsense mutation c.519C > T (p.R120X), which lack detectable RP2 protein. Translational read-through inducing drugs (TRIDs), such as PTC124, were able to restore Kif7 levels at the ciliary tip of RP2 null cells. Collectively, our findings suggest that RP2 and Arl3 regulate the trafficking of specific kinesins to cilia tips and provide additional evidence that TRIDs could be clinically beneficial for patients with this retinal degeneration.
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Affiliation(s)
- Nele Schwarz
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Amelia Lane
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | | | | | | | - Clare L. Thompson
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, UK
| | - Lyndon da Cruz
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital, London EC1V 2PD, UK
| | | | - J. Paul Chapple
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, UK
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236
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Ivanova AA, Caspary T, Seyfried NT, Duong DM, West AB, Liu Z, Kahn RA. Biochemical characterization of purified mammalian ARL13B protein indicates that it is an atypical GTPase and ARL3 guanine nucleotide exchange factor (GEF). J Biol Chem 2017; 292:11091-11108. [PMID: 28487361 PMCID: PMC5491791 DOI: 10.1074/jbc.m117.784025] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/02/2017] [Indexed: 12/11/2022] Open
Abstract
Primary cilia play central roles in signaling during metazoan development. Several key regulators of ciliogenesis and ciliary signaling are mutated in humans, resulting in a number of ciliopathies, including Joubert syndrome (JS). ARL13B is a ciliary GTPase with at least three missense mutations identified in JS patients. ARL13B is a member of the ADP ribosylation factor family of regulatory GTPases, but is atypical in having a non-homologous, C-terminal domain of ∼20 kDa and at least one key residue difference in the consensus GTP-binding motifs. For these reasons, and to establish a solid biochemical basis on which to begin to model its actions in cells and animals, we developed preparations of purified, recombinant, murine Arl13b protein. We report results from assays for solution-based nucleotide binding, intrinsic and GTPase-activating protein-stimulated GTPase, and ARL3 guanine nucleotide exchange factor activities. Biochemical analyses of three human missense mutations found in JS and of two consensus GTPase motifs reinforce the atypical properties of this regulatory GTPase. We also discovered that murine Arl13b is a substrate for casein kinase 2, a contaminant in our preparation from human embryonic kidney cells. This activity, and the ability of casein kinase 2 to use GTP as a phosphate donor, may be a source of differences between our data and previously published results. These results provide a solid framework for further research into ARL13B on which to develop models for the actions of this clinically important cell regulator.
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Affiliation(s)
| | - Tamara Caspary
- Human Genetics, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | | | | | - Andrew B West
- the Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Zhiyong Liu
- the Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama 35294
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237
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Kon E, Cossard A, Jossin Y. Neuronal Polarity in the Embryonic Mammalian Cerebral Cortex. Front Cell Neurosci 2017; 11:163. [PMID: 28670267 PMCID: PMC5472699 DOI: 10.3389/fncel.2017.00163] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/26/2017] [Indexed: 11/13/2022] Open
Abstract
The cerebral cortex is composed of billions of neurons that can grossly be subdivided into two broad classes: inhibitory GABAergic interneurons and excitatory glutamatergic neurons. The majority of cortical neurons in mammals are the excitatory type and they are the main focus of this review article. Like many of the cells in multicellular organisms, fully differentiated neurons are both morphologically and functionally polarized. However, they go through several changes in polarity before reaching this final mature differentiated state. Neurons are derived from polarized neuronal progenitor/stem cells and their commitment to neuronal fate is decided by cellular and molecular asymmetry during their last division in the neurogenic zone. They migrate from their birthplace using so-called multipolar migration, during which they switch direction of movement several times, and repolarize for bipolar migration when the axon is specified. Therefore, neurons have to break their previous symmetry, change their morphology and adequately respond to polarizing signals during migration in order to reach the correct position in the cortex and start making connections. Finally, the dendritic tree is elaborated and the axon/dendrite morphological polarity is set. Here we will describe the function, establishment and maintenance of polarity during the different developmental steps starting from neural stem cell (NSC) division, neuronal migration and axon specification at embryonic developmental stages.
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Affiliation(s)
- Elif Kon
- Mammalian Development and Cell Biology Unit, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Alexia Cossard
- Mammalian Development and Cell Biology Unit, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
| | - Yves Jossin
- Mammalian Development and Cell Biology Unit, Institute of Neuroscience, Université catholique de LouvainBrussels, Belgium
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238
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Michiue T, Yamamoto T, Yasuoka Y, Goto T, Ikeda T, Nagura K, Nakayama T, Taira M, Kinoshita T. High variability of expression profiles of homeologous genes for Wnt, Hh, Notch, and Hippo signaling pathways in Xenopus laevis. Dev Biol 2017; 426:270-290. [DOI: 10.1016/j.ydbio.2016.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 11/29/2016] [Accepted: 12/05/2016] [Indexed: 10/20/2022]
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239
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Song P, Dudinsky L, Fogerty J, Gaivin R, Perkins BD. Arl13b Interacts With Vangl2 to Regulate Cilia and Photoreceptor Outer Segment Length in Zebrafish. Invest Ophthalmol Vis Sci 2017; 57:4517-26. [PMID: 27571019 PMCID: PMC5015978 DOI: 10.1167/iovs.16-19898] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Mutations in the gene ARL13B cause the classical form of Joubert syndrome, an autosomal recessive ciliopathy with variable degrees of retinal degeneration. As second-site modifier alleles can contribute to retinal pathology in ciliopathies, animal models provide a unique platform to test how genetic interactions modulate specific phenotypes. In this study, we analyzed the zebrafish arl13b mutant for retinal degeneration and for epistatic relationships with the planar cell polarity protein (PCP) component vangl2. METHODS Photoreceptor and cilia structure was examined by light and electron microscopy. Immunohistochemistry was performed to examine ciliary markers. Genetic interactions were tested by pairwise crosses of heterozygous animals. Genetic mosaic animals were generated by blastula transplantation and analyzed by fluorescence microscopy. RESULTS At 5 days after fertilization, photoreceptor outer segments were shorter in zebrafish arl13b-/- mutants compared to wild-type larvae, no overt signs of retinal degeneration were observed by light or electron microscopy. Starting at 14 days after fertilization (dpf) and continuing through 30 dpf, cells lacking Arl13b died following transplantation into wild-type host animals. Photoreceptors of arl13b-/-;vangl2-/- mutants were more compromised than the photoreceptors of single mutants. Finally, when grown within a wild-type retina, the vangl2-/- mutant cone photoreceptors displayed normal basal body positioning. CONCLUSIONS We show that arl13b-/- mutants have shortened cilia and photoreceptor outer segments and exhibit a slow, progressive photoreceptor degeneration that occurs over weeks. The data suggest that loss of Arl13b leads to slow photoreceptor degeneration, but can be exacerbated by the loss of vangl2. Importantly, the data show that Arl13b can genetically and physically interact with Vangl2 and this association is important for normal photoreceptor structure. The loss of vangl2, however, does not affect basal body positioning.
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Affiliation(s)
- Ping Song
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Lynn Dudinsky
- Department of Biology, Texas A&M University, College Station, Texas, United States
| | - Joseph Fogerty
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Robert Gaivin
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Brian D Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States 2Department of Biology, Texas A&M University, College Station, Texas, United States
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240
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Tian H, Feng J, Li J, Ho TV, Yuan Y, Liu Y, Brindopke F, Figueiredo JC, Magee W, Sanchez-Lara PA, Chai Y. Intraflagellar transport 88 (IFT88) is crucial for craniofacial development in mice and is a candidate gene for human cleft lip and palate. Hum Mol Genet 2017; 26:860-872. [PMID: 28069795 DOI: 10.1093/hmg/ddx002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 01/03/2016] [Indexed: 01/08/2023] Open
Abstract
Ciliopathies are pleiotropic human diseases resulting from defects of the primary cilium, and these patients often have cleft lip and palate. IFT88 is required for the assembly and function of the primary cilia, which mediate the activity of key developmental signaling pathways. Through whole exome sequencing of a family of three affected siblings with isolated cleft lip and palate, we discovered that they share a novel missense mutation in IFT88 (c.915G > C, p.E305D), suggesting this gene should be considered a candidate for isolated orofacial clefting. In order to evaluate the function of IFT88 in regulating craniofacial development, we generated Wnt1-Cre;Ift88fl/fl mice to eliminate Ift88 specifically in cranial neural crest (CNC) cells. Wnt1-Cre;Ift88fl/flpups died at birth due to severe craniofacial defects including bilateral cleft lip and palate and tongue agenesis, following the loss of the primary cilia in the CNC-derived palatal mesenchyme. Loss of Ift88 also resulted in a decrease in neural crest cell proliferation during early stages of palatogenesis as well as a downregulation of the Shh signaling pathway in the palatal mesenchyme. Importantly, Osr2KI-Cre;Ift88fl/flmice, in which Ift88 is lost specifically in the palatal mesenchyme, exhibit isolated cleft palate. Taken together, our results demonstrate that IFT88 has a highly conserved function within the primary cilia of the CNC-derived mesenchyme in the lip and palate region in mice and is a strong candidate as an orofacial clefting gene in humans.
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Affiliation(s)
- Hua Tian
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA.,Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Jifan Feng
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Jingyuan Li
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA.,Molecular Laboratory for Gene Therapy and Tooth Regeneration, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing 100050, China
| | - Thach-Vu Ho
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Yuan Yuan
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Yang Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Frederick Brindopke
- Division of Plastic and Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Jane C Figueiredo
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - William Magee
- Division of Plastic and Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Pedro A Sanchez-Lara
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA.,Center for Personalized Medicine, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA.,Department of Pathology & Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Yang Chai
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
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241
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Bangs F, Anderson KV. Primary Cilia and Mammalian Hedgehog Signaling. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a028175. [PMID: 27881449 DOI: 10.1101/cshperspect.a028175] [Citation(s) in RCA: 400] [Impact Index Per Article: 57.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
It has been a decade since it was discovered that primary cilia have an essential role in Hedgehog (Hh) signaling in mammals. This discovery came from screens in the mouse that identified a set of genes that are required for both normal Hh signaling and for the formation of primary cilia. Since then, dozens of mouse mutations have been identified that disrupt cilia in a variety of ways and have complex effects on Hedgehog signaling. Here, we summarize the genetic and developmental studies used to deduce how Hedgehog signal transduction is linked to cilia and the complex effects that perturbation of cilia structure can have on Hh signaling. We conclude by describing the current status of our understanding of the cell-type-specific regulation of ciliogenesis and how that determines the ability of cells to respond to Hedgehog ligands.
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Affiliation(s)
- Fiona Bangs
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065
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242
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Saade M, Gonzalez-Gobartt E, Escalona R, Usieto S, Martí E. Shh-mediated centrosomal recruitment of PKA promotes symmetric proliferative neuroepithelial cell division. Nat Cell Biol 2017; 19:493-503. [PMID: 28446817 DOI: 10.1038/ncb3512] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 03/16/2017] [Indexed: 12/18/2022]
Abstract
Tight control of the balance between self-expanding symmetric and self-renewing asymmetric neural progenitor divisions is crucial to regulate the number of cells in the developing central nervous system. We recently demonstrated that Sonic hedgehog (Shh) signalling is required for the expansion of motor neuron progenitors by maintaining symmetric divisions. Here we show that activation of Shh/Gli signalling in dividing neuroepithelial cells controls the symmetric recruitment of PKA to the centrosomes that nucleate the mitotic spindle, maintaining symmetric proliferative divisions. Notably, Shh signalling upregulates the expression of pericentrin, which is required to dock PKA to the centrosomes, which in turn exerts a positive feedback onto Shh signalling. Thus, by controlling centrosomal protein assembly, we propose that Shh signalling overcomes the intrinsic asymmetry at the centrosome during neuroepithelial cell division, thereby promoting self-expanding symmetric divisions and the expansion of the progenitor pool.
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Affiliation(s)
- Murielle Saade
- Instituto de Biología Molecular de Barcelona, CSIC, ParcCientífic de Barcelona, C/Baldiri i Reixac 20, Barcelona 08028, Spain
| | - Elena Gonzalez-Gobartt
- Instituto de Biología Molecular de Barcelona, CSIC, ParcCientífic de Barcelona, C/Baldiri i Reixac 20, Barcelona 08028, Spain
| | - Rene Escalona
- Instituto de Biología Molecular de Barcelona, CSIC, ParcCientífic de Barcelona, C/Baldiri i Reixac 20, Barcelona 08028, Spain
| | - Susana Usieto
- Instituto de Biología Molecular de Barcelona, CSIC, ParcCientífic de Barcelona, C/Baldiri i Reixac 20, Barcelona 08028, Spain
| | - Elisa Martí
- Instituto de Biología Molecular de Barcelona, CSIC, ParcCientífic de Barcelona, C/Baldiri i Reixac 20, Barcelona 08028, Spain
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243
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Nechipurenko IV, Berciu C, Sengupta P, Nicastro D. Centriolar remodeling underlies basal body maturation during ciliogenesis in Caenorhabditis elegans. eLife 2017; 6. [PMID: 28411364 PMCID: PMC5392363 DOI: 10.7554/elife.25686] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/15/2017] [Indexed: 12/31/2022] Open
Abstract
The primary cilium is nucleated by the mother centriole-derived basal body (BB) via as yet poorly characterized mechanisms. BBs have been reported to degenerate following ciliogenesis in the C. elegans embryo, although neither BB architecture nor early ciliogenesis steps have been described in this organism. In a previous study (Doroquez et al., 2014), we described the three-dimensional morphologies of sensory neuron cilia in adult C. elegans hermaphrodites at high resolution. Here, we use serial section electron microscopy and tomography of staged C. elegans embryos to demonstrate that BBs remodel to support ciliogenesis in a subset of sensory neurons. We show that centriolar singlet microtubules are converted into BB doublets which subsequently grow asynchronously to template the ciliary axoneme, visualize degeneration of the centriole core, and define the developmental stage at which the transition zone is established. Our work provides a framework for future investigations into the mechanisms underlying BB remodeling. DOI:http://dx.doi.org/10.7554/eLife.25686.001
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Affiliation(s)
- Inna V Nechipurenko
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, United States
| | - Cristina Berciu
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, United States
| | - Piali Sengupta
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, United States
| | - Daniela Nicastro
- Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, United States.,Departments of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, United States
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244
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Shimada IS, Badgandi H, Somatilaka BN, Mukhopadhyay S. Using Primary Neurosphere Cultures to Study Primary Cilia. J Vis Exp 2017. [PMID: 28448009 DOI: 10.3791/55315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The primary cilium is fundamentally important for the proliferation of neural stem/progenitor cells and for neuronal differentiation during embryonic, postnatal, and adult life. In addition, most differentiated neurons possess primary cilia that house signaling receptors, such as G-protein-coupled receptors, and signaling molecules, such as adenylyl cyclases. The primary cilium determines the activity of multiple developmental pathways, including the sonic hedgehog pathway during embryonic neuronal development, and also functions in promoting compartmentalized subcellular signaling during adult neuronal function. Unsurprisingly, defects in primary cilium biogenesis and function have been linked to developmental anomalies of the brain, central obesity, and learning and memory deficits. Thus, it is imperative to study primary cilium biogenesis and ciliary trafficking in the context of neural stem/progenitor cells and differentiated neurons. However, culturing methods for primary neurons require considerable expertise and are not amenable to freeze-thaw cycles. In this protocol, we discuss culturing methods for mixed populations of neural stem/progenitor cells using primary neurospheres. The neurosphere-based culturing methods provide the combined benefits of studying primary neural stem/progenitor cells: amenability to multiple passages and freeze-thaw cycles, differentiation potential into neurons/glia, and transfectability. Importantly, we determined that neurosphere-derived neural stem/progenitor cells and differentiated neurons are ciliated in culture and localize signaling molecules relevant to ciliary function in these compartments. Utilizing these cultures, we further describe methods to study ciliogenesis and ciliary trafficking in neural stem/progenitor cells and differentiated neurons. These neurosphere-based methods allow us to study cilia-regulated cellular pathways, including G-protein-coupled receptor and sonic hedgehog signaling, in the context of neural stem/progenitor cells and differentiated neurons.
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Affiliation(s)
- Issei S Shimada
- Department of Cell Biology, University of Texas Southwestern Medical Center;
| | - Hemant Badgandi
- Department of Cell Biology, University of Texas Southwestern Medical Center
| | | | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center;
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245
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Luo W, Yi H, Taylor J, Li JD, Chi F, Todd NW, Lin X, Ren D, Chen P. Cilia distribution and polarity in the epithelial lining of the mouse middle ear cavity. Sci Rep 2017; 7:45870. [PMID: 28358397 PMCID: PMC5372464 DOI: 10.1038/srep45870] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 03/03/2017] [Indexed: 12/15/2022] Open
Abstract
The middle ear conducts sound to the cochlea for hearing. Otitis media (OM) is the most common illness in childhood. Moreover, chronic OM with effusion (COME) is the leading cause of conductive hearing loss. Clinically, COME is highly associated with Primary Ciliary Dyskinesia, implicating significant contributions of cilia dysfunction to COME. The understanding of middle ear cilia properties that are critical to OM susceptibility, however, is limited. Here, we confirmed the presence of a ciliated region near the Eustachian tube orifice at the ventral region of the middle ear cavity, consisting mostly of a lumen layer of multi-ciliated and a layer of Keratin-5-positive basal cells. We also found that the motile cilia are polarized coordinately and display a planar cell polarity. Surprisingly, we also found a region of multi-ciliated cells that line the posterior dorsal pole of the middle ear cavity which was previously thought to contain only non-ciliated cells. Our study provided a more complete understanding of cilia distribution and revealed for the first time coordinated polarity of cilia in the epithelium of the mammalian middle ear, thus illustrating novel structural features that are likely critical for middle ear functions and related to OM susceptibility.
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Affiliation(s)
- Wenwei Luo
- Department of Cell Biology Emory University, Atlanta, USA.,Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai, PR China
| | - Hong Yi
- Electronic Microscopy Laboratory, Emory University, Atlanta, USA
| | - Jeannette Taylor
- Electronic Microscopy Laboratory, Emory University, Atlanta, USA
| | - Jian-Dong Li
- Center for Inflammation, Immunity and Infection, Institution for Biomedical Sciences, Georgia State University, Atlanta, USA
| | - Fanglu Chi
- Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai, PR China
| | - N Wendell Todd
- Department of Otolaryngology, Emory University, Atlanta, USA
| | - Xi Lin
- Department of Otolaryngology, Emory University, Atlanta, USA
| | - Dongdong Ren
- Eye, Ear, Nose, and Throat Hospital, Fudan University, Shanghai, PR China
| | - Ping Chen
- Department of Cell Biology Emory University, Atlanta, USA
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246
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Unique spatiotemporal requirements for intraflagellar transport genes during forebrain development. PLoS One 2017; 12:e0173258. [PMID: 28291836 PMCID: PMC5349613 DOI: 10.1371/journal.pone.0173258] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/17/2017] [Indexed: 12/26/2022] Open
Abstract
Primary cilia are organelles extended from virtually all cells and are required for the proper regulation of a number of canonical developmental pathways. The role in cortical development of proteins important for ciliary form and function is a relatively understudied area. Here we have taken a genetic approach to define the role in forebrain development of three intraflagellar transport proteins known to be important for primary cilia function. We have genetically ablated Kif3a, Ift88, and Ttc21b in a series of specific spatiotemporal domains. The resulting phenotypes allow us to draw several conclusions. First, we conclude that the Ttc21b cortical phenotype is not due to the activity of Ttc21b within the brain itself. Secondly, some of the most striking phenotypes are from ablations in the neural crest cells and the adjacent surface ectoderm indicating that cilia transduce critical tissue—tissue interactions in the developing embryonic head. Finally, we note striking differences in phenotypes from ablations only one embryonic day apart, indicating very discrete spatiotemporal requirements for these three genes in cortical development.
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247
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Goetz SC, Bangs F, Barrington CL, Katsanis N, Anderson KV. The Meckel syndrome- associated protein MKS1 functionally interacts with components of the BBSome and IFT complexes to mediate ciliary trafficking and hedgehog signaling. PLoS One 2017; 12:e0173399. [PMID: 28291807 PMCID: PMC5349470 DOI: 10.1371/journal.pone.0173399] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/20/2017] [Indexed: 12/04/2022] Open
Abstract
The importance of primary cilia in human health is underscored by the link between ciliary dysfunction and a group of primarily recessive genetic disorders with overlapping clinical features, now known as ciliopathies. Many of the proteins encoded by ciliopathy-associated genes are components of a handful of multi-protein complexes important for the transport of cargo to the basal body and/or into the cilium. A key question is whether different complexes cooperate in cilia formation, and whether they participate in cilium assembly in conjunction with intraflagellar transport (IFT) proteins. To examine how ciliopathy protein complexes might function together, we have analyzed double mutants of an allele of the Meckel syndrome (MKS) complex protein MKS1 and the BBSome protein BBS4. We find that Mks1; Bbs4 double mutant mouse embryos exhibit exacerbated defects in Hedgehog (Hh) dependent patterning compared to either single mutant, and die by E14.5. Cells from double mutant embryos exhibit a defect in the trafficking of ARL13B, a ciliary membrane protein, resulting in disrupted ciliary structure and signaling. We also examined the relationship between the MKS complex and IFT proteins by analyzing double mutant between Mks1 and a hypomorphic allele of the IFTB component Ift172. Despite each single mutant surviving until around birth, Mks1; Ift172avc1 double mutants die at mid-gestation, and exhibit a dramatic failure of cilia formation. We also find that Mks1 interacts genetically with an allele of Dync2h1, the IFT retrograde motor. Thus, we have demonstrated that the MKS transition zone complex cooperates with the BBSome to mediate trafficking of specific trans-membrane receptors to the cilium. Moreover, the genetic interaction of Mks1 with components of IFT machinery suggests that the transition zone complex facilitates IFT to promote cilium assembly and structure.
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Affiliation(s)
- Sarah C. Goetz
- Program in Developmental Biology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave. New York, United States of America
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States of America
| | - Fiona Bangs
- Program in Developmental Biology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave. New York, United States of America
| | - Chloe L. Barrington
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, United States of America
| | - Nicholas Katsanis
- Department of Cell Biology and Center for Human Disease Modeling, Duke University Medical Center, Durham, NC, United States of America
| | - Kathryn V. Anderson
- Program in Developmental Biology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave. New York, United States of America
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248
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Xin D, Christopher KJ, Zeng L, Kong Y, Weatherbee SD. IFT56 regulates vertebrate developmental patterning by maintaining IFTB complex integrity and ciliary microtubule architecture. Development 2017; 144:1544-1553. [PMID: 28264835 DOI: 10.1242/dev.143255] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 02/27/2017] [Indexed: 12/19/2022]
Abstract
Cilia are key regulators of animal development and depend on intraflagellar transport (IFT) proteins for their formation and function, yet the roles of individual IFT proteins remain unclear. We examined the Ift56hop mouse mutant and reveal novel insight into the function of IFT56, a poorly understood IFTB protein. Ift56hop mice have normal cilia distribution but display defective cilia structure, including abnormal positioning and number of ciliary microtubule doublets. We show that Ift56hop cilia are unable to accumulate Gli proteins efficiently, resulting in developmental patterning defects in Shh signaling-dependent tissues such as the limb and neural tube. Strikingly, core IFTB proteins are unable to accumulate normally within Ift56hop cilia, including IFT88, IFT81 and IFT27, which are crucial for key processes such as tubulin transport and Shh signaling. IFT56 is required specifically for the IFTB complex, as IFTA components and proteins that rely on IFTA function are unaffected in Ift56hop cilia. These studies define a distinct and novel role for IFT56 in IFTB complex integrity that is crucial for cilia structure and function and, ultimately, animal development.
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Affiliation(s)
- Daisy Xin
- Department of Genetics, Yale University, New Haven, CT 06520, USA
| | | | - Lewie Zeng
- Department of Genetics, Yale University, New Haven, CT 06520, USA
| | - Yong Kong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.,W.M. Keck Foundation Biotechnology Resource Laboratory, Yale University, New Haven, CT 06520, USA
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249
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Pintado P, Sampaio P, Tavares B, Montenegro-Johnson TD, Smith DJ, Lopes SS. Dynamics of cilia length in left-right development. ROYAL SOCIETY OPEN SCIENCE 2017; 4:161102. [PMID: 28405397 PMCID: PMC5383854 DOI: 10.1098/rsos.161102] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 02/06/2017] [Indexed: 05/28/2023]
Abstract
Reduction in the length of motile cilia in the zebrafish left-right organizer (LRO), also known as Kupffer's vesicle, has a large impact on left-right development. Here we demonstrate through genetic overexpression in zebrafish embryos and mathematical modelling that the impact of increased motile cilia length in embryonic LRO fluid flow is milder than that of short cilia. Through Arl13b overexpression, which increases cilia length without impacting cilia beat frequency, we show that the increase in cilium length is associated with a decrease in beat amplitude, resulting in similar flow strengths for Arl13b overexpression and wild-type (WT) embryos, which were not predicted by current theory. Longer cilia exhibit pronounced helical beat patterns and, consequently, lower beat amplitudes relative to WT, a result of an elastohydrodynamic shape transition. For long helical cilia, fluid dynamics modelling predicts a mild (approx. 12%) reduction in the torque exerted on the fluid relative to the WT, resulting in a proportional reduction in flow generation. This mild reduction is corroborated by experiments, providing a mechanism for the mild impact on organ situs.
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Affiliation(s)
- P. Pintado
- NOVA Medical School Faculdade de Ciências Médicas, Chronic Diseases Research Centre, CEDOC, Universidade Nova de Lisboa, Campo Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
| | - P. Sampaio
- NOVA Medical School Faculdade de Ciências Médicas, Chronic Diseases Research Centre, CEDOC, Universidade Nova de Lisboa, Campo Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
| | - B. Tavares
- NOVA Medical School Faculdade de Ciências Médicas, Chronic Diseases Research Centre, CEDOC, Universidade Nova de Lisboa, Campo Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
| | | | - D. J. Smith
- School of Mathematics, University of Birmingham, Birmingham, UK
- Institute for Metabolism and Systems Research, University of Birmingham, Birmingham, UK
- Centre for Human Reproductive Science, Birmingham Women's NHS Foundation Trust, Birmingham, UK
| | - S. S. Lopes
- NOVA Medical School Faculdade de Ciências Médicas, Chronic Diseases Research Centre, CEDOC, Universidade Nova de Lisboa, Campo Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
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250
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Nozaki S, Katoh Y, Terada M, Michisaka S, Funabashi T, Takahashi S, Kontani K, Nakayama K. Regulation of ciliary retrograde protein trafficking by the Joubert syndrome proteins ARL13B and INPP5E. J Cell Sci 2017; 130:563-576. [PMID: 27927754 DOI: 10.1242/jcs.197004] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/29/2016] [Indexed: 12/17/2022] Open
Abstract
ARL13B (a small GTPase) and INPP5E (a phosphoinositide 5-phosphatase) are ciliary proteins encoded by causative genes of Joubert syndrome. We here showed, by taking advantage of a visible immunoprecipitation assay, that ARL13B interacts with the IFT46 -: IFT56 (IFT56 is also known as TTC26) dimer of the intraflagellar transport (IFT)-B complex, which mediates anterograde ciliary protein trafficking. However, the ciliary localization of ARL13B was found to be independent of its interaction with IFT-B, but dependent on the ciliary-targeting sequence RVEP in its C-terminal region. ARL13B-knockout cells had shorter cilia than control cells and exhibited aberrant localization of ciliary proteins, including INPP5E. In particular, in ARL13B-knockout cells, the IFT-A and IFT-B complexes accumulated at ciliary tips, and GPR161 (a negative regulator of Hedgehog signaling) could not exit cilia in response to stimulation with Smoothened agonist. This abnormal phenotype was rescued by the exogenous expression of wild-type ARL13B, as well as by its mutant defective in the interaction with IFT-B, but not by its mutants defective in INPP5E binding or in ciliary localization. Thus, ARL13B regulates IFT-A-mediated retrograde protein trafficking within cilia through its interaction with INPP5E.
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Affiliation(s)
- Shohei Nozaki
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yohei Katoh
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masaya Terada
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Saki Michisaka
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Teruki Funabashi
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Senye Takahashi
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kenji Kontani
- Department of Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588, Japan
| | - Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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