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Bhargava S, Kulkarni R, Dewangan B, Kulkarni N, Jiaswar C, Kumar K, Kumar A, Bodhe PR, Kumar H, Sahu B. Microtubule stabilising peptides: new paradigm towards management of neuronal disorders. RSC Med Chem 2023; 14:2192-2205. [PMID: 37974959 PMCID: PMC10650357 DOI: 10.1039/d3md00012e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 08/09/2023] [Indexed: 11/19/2023] Open
Abstract
Neuronal cells made of soma, axon, and dendrites are highly compartmentalized and possess a specialized transport system that can convey long-distance electrical signals for the cross-talk. The transport system is made up of microtubule (MT) polymers and MT-binding proteins. MTs play vital and diverse roles in various cellular processes. Therefore, defects and dysregulation of MTs and their binding proteins lead to many neurological disorders as exemplified by Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, and many others. MT-stabilising agents (MSAs) altering the MT-associated protein connections have shown great potential for several neurodegenerative disorders. Peptides are an important class of molecules with high specificity, biocompatibility and are devoid of side effects. In the past, peptides have been explored in various neuronal disorders as therapeutics. Davunetide, a MT-stabilising octapeptide, has entered into phase II clinical trials for schizophrenia. Numerous examples of peptides emerging as MSAs reflect the emergence of a new paradigm for peptides which can be explored further as drug candidates for neuronal disorders. Although small molecule-based MSAs have been reviewed in the past, there is no systematic review in recent years focusing on peptides as MSAs apart from davunetide in 2013. Therefore, a systematic updated review on MT stabilising peptides may shed light on many hidden aspects and enable researchers to develop new therapies for diseases related to the CNS. In this review we have summarised the recent examples of peptides as MSAs.
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Affiliation(s)
- Shubhangi Bhargava
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Riya Kulkarni
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Bhaskar Dewangan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Neeraj Kulkarni
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Chirag Jiaswar
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Kunal Kumar
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Amit Kumar
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Praveen Reddy Bodhe
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Hemant Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research Ahmedabad India
| | - Bichismita Sahu
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Ahmedabad India
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2
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Nukala KM, Lilienthal AJ, Lye SH, Bassuk AG, Chtarbanova S, Manak JR. Downregulation of oxidative stress-mediated glial innate immune response suppresses seizures in a fly epilepsy model. Cell Rep 2023; 42:112004. [PMID: 36641750 PMCID: PMC9942582 DOI: 10.1016/j.celrep.2023.112004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 11/30/2022] [Accepted: 01/03/2023] [Indexed: 01/15/2023] Open
Abstract
Previous work in our laboratory has shown that mutations in prickle (pk) cause myoclonic-like seizures and ataxia in Drosophila, similar to what is observed in humans carrying mutations in orthologous PRICKLE genes. Here, we show that pk mutant brains show elevated, sustained neuronal cell death that correlates with increasing seizure penetrance, as well as an upregulation of mitochondrial oxidative stress and innate immune response (IIR) genes. Moreover, flies exhibiting more robust seizures show increased levels of IIR-associated target gene expression suggesting they may be linked. Genetic knockdown in glia of either arm of the IIR (Immune Deficiency [Imd] or Toll) leads to a reduction in neuronal death, which in turn suppresses seizure activity, with oxidative stress acting upstream of IIR. These data provide direct genetic evidence that oxidative stress in combination with glial-mediated IIR leads to progression of an epilepsy disorder.
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Affiliation(s)
- Krishna M Nukala
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA
| | | | - Shu Hui Lye
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA
| | - Alexander G Bassuk
- Department of Pediatrics, University of Iowa and Carver College of Medicine, Iowa City, IA 52242, USA; Department of Neurology, University of Iowa and Carver College of Medicine, Iowa City, IA 52242, USA; The Iowa Neuroscience Institute, University of Iowa and Carver College of Medicine, Iowa City, IA 52242, USA
| | | | - J Robert Manak
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA; Department of Pediatrics, University of Iowa and Carver College of Medicine, Iowa City, IA 52242, USA.
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3
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Eckel BD, Cruz R, Craig EM, Baas PW. Microtubule polarity flaws as a treatable driver of neurodegeneration. Brain Res Bull 2023; 192:208-215. [PMID: 36442694 DOI: 10.1016/j.brainresbull.2022.11.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/07/2022] [Accepted: 11/17/2022] [Indexed: 11/26/2022]
Abstract
Microtubule disruption is a common downstream mechanism leading to axonal degeneration in a number of neurological diseases. To date, most studies on this topic have focused on the loss of microtubule mass from the axon, as well as changes in the stability properties of the microtubules and/or their tubulin composition. Here we posit corruption of the normal pattern of microtubule polarity orientation as an underappreciated and yet treatable contributor to axonal degeneration. We include computational modeling to fortify the rigor of our considerations. Our simulations demonstrate that even a small deviation from the usual polarity pattern of axonal microtubules is detrimental to motor-based trafficking of organelles and other intracellular cargo. Additional modeling predicts that axons with such deviations will exhibit significantly reduced speed and reliability of organelle transport, and that localized clusters of wrongly oriented microtubules will result in traffic jams of accumulated organelles.
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Affiliation(s)
- Bridie D Eckel
- Dept Neurobiol/Anat, Drexel University, 2900 Queen Lane, Philadelphia, PA 19129, USA
| | - Roy Cruz
- Dept Physics, Central Washington University, Ellensburg, WA 98926, USA
| | - Erin M Craig
- Dept Physics, Central Washington University, Ellensburg, WA 98926, USA
| | - Peter W Baas
- Dept Neurobiol/Anat, Drexel University, 2900 Queen Lane, Philadelphia, PA 19129, USA.
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4
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Chen Y, Liu TT, Niu M, Li X, Wang X, Liu T, Li Y. Epilepsy gene prickle ensures neuropil glial ensheathment through regulating cell adhesion molecules. iScience 2022; 26:105731. [PMID: 36582832 PMCID: PMC9792895 DOI: 10.1016/j.isci.2022.105731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 07/27/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
Human PRICKLE1 gene has been associated with epilepsy. However, the underlying pathogenetic mechanisms remain elusive. Here we report a Drosophila prickle mutant pk IG1-1 exhibiting strong epileptic seizures and, intriguingly, abnormal glial wrapping. We found that pk is required in both neurons and glia, particularly neuropil ensheathing glia (EGN), the fly analog of oligodendrocyte, for protecting the animal from seizures. We further revealed that Pk directly binds to the membrane skeleton binding protein Ankyrin 2 (Ank2), thereby regulating the cell adhesion molecule Neuroglian (Nrg). Such protein interactions also apply to their human homologues. Moreover, nrg and ank2 mutant flies also display seizure phenotypes, and expression of either Nrg or Ank2 rescues the seizures of pk IG1-1 flies. Therefore, our findings indicate that Prickle ensures neuron-glial interaction within neuropils through regulating cell adhesion between neurons and ensheathing glia. Dysregulation of this process may represent a conserved pathogenic mechanism underlying PRICKLE1-associated epilepsy.
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Affiliation(s)
- Yanbo Chen
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China,Corresponding author
| | - Tong-Tong Liu
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengxia Niu
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaoting Li
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinwei Wang
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tong Liu
- International Academic Center of Complex Systems, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Yan Li
- Institute of Biophysics, State Key Laboratory of Brain and Cognitive Science, Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing 100101, China,University of Chinese Academy of Sciences, Beijing 100049, China,Corresponding author
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5
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Lilienthal AJ, Parida M, Manak JR. Characterization of prickle isoform-specific pk pk1 and pk sple1 mutations in Drosophila melanogaster. MICROPUBLICATION BIOLOGY 2022; 2022:10.17912/micropub.biology.000656. [PMID: 36338150 PMCID: PMC9634456 DOI: 10.17912/micropub.biology.000656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 05/10/2023]
Abstract
We used paired-end next generation sequencing (NGS) to characterize the classic isoform-specific pk pk1 and pk sple1 mutations of the prickle gene in Drosophila melanogaster . Here we provide evidence that these previously reported null mutations are caused by either a tirant transposon insertion into the 5' UTR of pk pk1 or a premature stop codon in the second exon of pk sple1 . Additional likely benign missense mutations were identified in both mutant isoforms.
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Affiliation(s)
| | | | - J Robert Manak
- Dept of Biology, University of Iowa
- Dept of Pediatrics, University of Iowa, Iowa City, IA, USA
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Kunimoto K, Weiner AT, Axelrod JD, Vladar EK. Distinct overlapping functions for Prickle1 and Prickle2 in the polarization of the airway epithelium. Front Cell Dev Biol 2022; 10:976182. [PMID: 36176272 PMCID: PMC9513604 DOI: 10.3389/fcell.2022.976182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Planar cell polarity (PCP) signaling polarizes cells within the plane of an epithelium. In the airways, planar cell polarity signaling orients the directional beating of motile cilia required for effective mucociliary clearance. The planar cell polarity signaling mechanism is best understood from work in Drosophila, where it has been shown to both coordinate the axis of polarity between cells and to direct the morphological manifestations of polarization within cells. The ‘core’ planar cell polarity signaling mechanism comprises two protein complexes that segregate to opposite sides of each cell and interact with the opposite complex in neighboring cells. Proper subcellular localization of core planar cell polarity proteins correlates with, and is almost certainly responsible for, their ability to direct polarization. This mechanism is highly conserved from Drosophila to vertebrates, though for most of the core genes, mammals have multiple paralogs whereas Drosophila has only one. In the mouse airway epithelium, the core protein Prickle2 segregates asymmetrically, as is characteristic for core proteins, but is only present in multiciliated cells and is absent from other cell types. Furthermore, Prickle2 mutant mice show only modest ciliary polarity defects. These observations suggest that other Prickle paralogs might contribute to polarization. Here, we show that Prickle1 segregates asymmetrically in multiciliated and nonciliated airway epithelial cell types, that compared to Prickle2, Prickle1 has different spatial and temporal expression dynamics and a stronger ciliary polarity phenotype, and that Prickle1 and Prickle2 mutants genetically interact. We propose distinct and partially overlapping functions for the Prickle paralogs in polarization of the airway epithelium.
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Affiliation(s)
- Koshi Kunimoto
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, United States
| | - Alexis T. Weiner
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, United States
| | - Jeffrey D. Axelrod
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, United States
| | - Eszter K. Vladar
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, United States
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, United States
- *Correspondence: Eszter K. Vladar,
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Dorrego-Rivas A, Ezan J, Moreau MM, Poirault-Chassac S, Aubailly N, De Neve J, Blanchard C, Castets F, Fréal A, Battefeld A, Sans N, Montcouquiol M. The core PCP protein Prickle2 regulates axon number and AIS maturation by binding to AnkG and modulating microtubule bundling. SCIENCE ADVANCES 2022; 8:eabo6333. [PMID: 36083912 PMCID: PMC9462691 DOI: 10.1126/sciadv.abo6333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Core planar cell polarity (PCP) genes, which are involved in various neurodevelopmental disorders such as neural tube closure, epilepsy, and autism spectrum disorder, have poorly defined molecular signatures in neurons, mostly synapse-centric. Here, we show that the core PCP protein Prickle-like protein 2 (Prickle2) controls neuronal polarity and is a previously unidentified member of the axonal initial segment (AIS) proteome. We found that Prickle2 is present and colocalizes with AnkG480, the AIS master organizer, in the earliest stages of axonal specification and AIS formation. Furthermore, by binding to and regulating AnkG480, Prickle2 modulates its ability to bundle microtubules, a crucial mechanism for establishing neuronal polarity and AIS formation. Prickle2 depletion alters cytoskeleton organization, and Prickle2 levels determine both axon number and AIS maturation. Last, early Prickle2 depletion produces impaired action potential firing.
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Affiliation(s)
- Ana Dorrego-Rivas
- Univ. Bordeaux, INSERM, Magendie, U1215, F-33077 Bordeaux, France
- Corresponding author.
| | - Jerome Ezan
- Univ. Bordeaux, INSERM, Magendie, U1215, F-33077 Bordeaux, France
| | - Maïté M Moreau
- Univ. Bordeaux, INSERM, Magendie, U1215, F-33077 Bordeaux, France
| | | | | | - Julie De Neve
- Univ. Bordeaux, INSERM, Magendie, U1215, F-33077 Bordeaux, France
| | | | - Francis Castets
- Aix-Marseille Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France
| | - Amélie Fréal
- Department of Functional Genomics, Vrije Universiteit (VU), Amsterdam, Netherlands
| | - Arne Battefeld
- Univ. Bordeaux, CNRS, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Nathalie Sans
- Univ. Bordeaux, INSERM, Magendie, U1215, F-33077 Bordeaux, France
- Corresponding author.
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Ueda A, O'Harrow TCDG, Xing X, Ehaideb S, Manak JR, Wu CF. Abnormal larval neuromuscular junction morphology and physiology in Drosophila prickle isoform mutants with known axonal transport defects and adult seizure behavior. J Neurogenet 2022; 36:65-73. [PMID: 35775303 DOI: 10.1080/01677063.2022.2093353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Previous studies have demonstrated the striking mutational effects of the Drosophila planar cell polarity gene prickle (pk) on larval motor axon microtubule-mediated vesicular transport and on adult epileptic behavior associated with neuronal circuit hyperexcitability. Mutant alleles of the prickle-prickle (pkpk) and prickle-spiny-legs (pksple) isoforms (hereafter referred to as pk and sple alleles, respectively) exhibit differential phenotypes. While both pk and sple affect larval motor axon transport, only sple confers motor circuit and behavior hyperexcitability. However, mutations in the two isoforms apparently counteract to ameliorate adult motor circuit and behavioral hyperexcitability in heteroallelic pkpk/pksple flies. We have further investigated the consequences of altered axonal transport in the development and function of the larval neuromuscular junction (NMJ). We uncovered robust dominant phenotypes in both pk and sple alleles, including synaptic terminal overgrowth (as revealed by anti-HRP and -Dlg immunostaining) and poor vesicle release synchronicity (as indicated by synaptic bouton focal recording). However, we observed recessive alteration of synaptic transmission only in pk/pk larvae, i.e. increased excitatory junctional potential (EJP) amplitude in pk/pk but not in pk/+ or sple/sple. Interestingly, for motor terminal excitability sustained by presynaptic Ca2+ channels, both pk and sple exerted strong effects to produce prolonged depolarization. Notably, only sple acted dominantly whereas pk/+ appeared normal, but was able to suppress the sple phenotypes, i.e. pk/sple appeared normal. Our observations contrast the differential roles of the pk and sple isoforms and highlight their distinct, variable phenotypic expression in the various structural and functional aspects of the larval NMJ.
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Affiliation(s)
- Atsushi Ueda
- Department of Biology, University of Iowa, Iowa City, IA, USA
| | | | - Xiaomin Xing
- Department of Biology, University of Iowa, Iowa City, IA, USA
| | - Salleh Ehaideb
- Department of Biology, University of Iowa, Iowa City, IA, USA.,Genetics Ph.D. Program, University of Iowa, Iowa City, IA, USA
| | - J Robert Manak
- Department of Biology, University of Iowa, Iowa City, IA, USA.,Genetics Ph.D. Program, University of Iowa, Iowa City, IA, USA.,Department of Pediatrics, University of Iowa, Iowa City, IA, USA.,Neuroscience Ph.D. Program, University of Iowa, Iowa City, IA, USA
| | - Chun-Fang Wu
- Department of Biology, University of Iowa, Iowa City, IA, USA.,Genetics Ph.D. Program, University of Iowa, Iowa City, IA, USA.,Neuroscience Ph.D. Program, University of Iowa, Iowa City, IA, USA
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9
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Casalia ML, Casabona JC, García C, Cavaliere Candedo V, Quintá HR, Farías MI, Gonzalez J, Gonzalez Morón D, Córdoba M, Consalvo D, Mostoslavsky G, Urbano FJ, Pasquini J, Murer MG, Rela L, Kauffman MA, Pitossi FJ. A familiar study on self-limited childhood epilepsy patients using hIPSC-derived neurons shows a bias towards immaturity at the morphological, electrophysiological and gene expression levels. Stem Cell Res Ther 2021; 12:590. [PMID: 34823607 PMCID: PMC8620942 DOI: 10.1186/s13287-021-02658-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 10/31/2021] [Indexed: 12/28/2022] Open
Abstract
Background Self-limited Childhood Epilepsies are the most prevalent epileptic syndrome in children. Its pathogenesis is unknown. In this disease, symptoms resolve spontaneously in approximately 50% of patients when maturity is reached, prompting to a maturation problem. The purpose of this study was to understand the molecular bases of this disease by generating and analyzing induced pluripotent stem cell-derived neurons from a family with 7 siblings, among whom 4 suffer from this disease.
Methods Two affected siblings and, as controls, a healthy sister and the unaffected mother of the family were studied. Using exome sequencing, a homozygous variant in the FYVE, RhoGEF and PH Domain Containing 6 gene was identified in the patients as a putative genetic factor that could contribute to the development of this familial disorder. After informed consent was signed, skin biopsies from the 4 individuals were collected, fibroblasts were derived and reprogrammed and neurons were generated and characterized by markers and electrophysiology. Morphological, electrophysiological and gene expression analyses were performed on these neurons. Results Bona fide induced pluripotent stem cells and derived neurons could be generated in all cases. Overall, there were no major shifts in neuronal marker expression among patient and control-derived neurons. Compared to two familial controls, neurons from patients showed shorter axonal length, a dramatic reduction in synapsin-1 levels and cytoskeleton disorganization. In addition, neurons from patients developed a lower action potential threshold with time of in vitro differentiation and the amount of current needed to elicit an action potential (rheobase) was smaller in cells recorded from NE derived from patients at 12 weeks of differentiation when compared with shorter times in culture. These results indicate an increased excitability in patient cells that emerges with the time in culture. Finally, functional genomic analysis showed a biased towards immaturity in patient-derived neurons. Conclusions We are reporting the first in vitro model of self-limited childhood epilepsy, providing the cellular bases for future in-depth studies to understand its pathogenesis. Our results show patient-specific neuronal features reflecting immaturity, in resonance with the course of the disease and previous imaging studies. Supplementary Information The online version contains supplementary material available at 10.1186/s13287-021-02658-2.
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Affiliation(s)
| | | | - Corina García
- Institute Leloir Foundation- IIBBA-CONICET, Buenos Aires, Argentina
| | | | - Héctor Ramiro Quintá
- CONICET and Laboratorio de Medicina Experimental "Dr. J Toblli", Hospital Alemán, Buenos Aires, Argentina
| | | | - Joaquín Gonzalez
- Institute Leloir Foundation- IIBBA-CONICET, Buenos Aires, Argentina
| | - Dolores Gonzalez Morón
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología "José María Ramos Mejía" Facultad de Medicina, UBA & Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, Universidad Austral-CONICET, Buenos Aires, Argentina
| | - Marta Córdoba
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología "José María Ramos Mejía" Facultad de Medicina, UBA & Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, Universidad Austral-CONICET, Buenos Aires, Argentina
| | - Damian Consalvo
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología "José María Ramos Mejía" Facultad de Medicina, UBA & Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, Universidad Austral-CONICET, Buenos Aires, Argentina
| | - Gustavo Mostoslavsky
- Center For Regenerative Medicine (CReM) of Boston University and Boston Medical Center, Boston, USA
| | - Francisco J Urbano
- Department of Physiology, Molecular and Cellular Biology "Dr. Héctor Maldonado", Faculty of Exact and Natural Sciences, University of Buenos Aires, IFIBYNE-CONICET, Buenos Aires, Argentina
| | - Juana Pasquini
- Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
| | - Mario Gustavo Murer
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Ciencias Fisiológicas, Grupo de Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires - CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Buenos Aires, Argentina
| | - Lorena Rela
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Ciencias Fisiológicas, Grupo de Neurociencia de Sistemas, Buenos Aires, Argentina.,Universidad de Buenos Aires - CONICET, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), Buenos Aires, Argentina
| | - Marcelo A Kauffman
- Consultorio y Laboratorio de Neurogenética, Centro Universitario de Neurología "José María Ramos Mejía" Facultad de Medicina, UBA & Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, Universidad Austral-CONICET, Buenos Aires, Argentina.
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10
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Abstract
Hypersynchronous neural activity is a characteristic feature of seizures. Although many Drosophila mutants of epilepsy-related genes display clear behavioral spasms and motor unit hyperexcitability, field potential measurements of aberrant hypersynchronous activity across brain regions during seizures have yet to be described. Here, we report a straightforward method to observe local field potentials (LFPs) from the Drosophila brain to monitor ensemble neural activity during seizures in behaving tethered flies. High frequency stimulation across the brain reliably triggers a stereotypic sequence of electroconvulsive seizure (ECS) spike discharges readily detectable in the dorsal longitudinal muscle (DLM) and coupled with behavioral spasms. During seizure episodes, the LFP signal displayed characteristic large-amplitude oscillations with a stereotypic temporal correlation to DLM flight muscle spiking. ECS-related LFP events were clearly distinct from rest- and flight-associated LFP patterns. We further characterized the LFP activity during different types of seizures originating from genetic and pharmacological manipulations. In the 'bang-sensitive' sodium channel mutant bangsenseless (bss), the LFP pattern was prolonged, and the temporal correlation between LFP oscillations and DLM discharges was altered. Following administration of the pro-convulsant GABAA blocker picrotoxin, we uncovered a qualitatively different LFP activity pattern, which consisted of a slow (1-Hz), repetitive, waveform, closely coupled with DLM bursting and behavioral spasms. Our approach to record brain LFPs presents an initial framework for electrophysiological analysis of the complex brain-wide activity patterns in the large collection of Drosophila excitability mutants.
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Affiliation(s)
- Atulya Iyengar
- Department of Biology, and Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Chun-Fang Wu
- Department of Biology, and Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
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11
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Characterization of Seizure Induction Methods in Drosophila. eNeuro 2021; 8:ENEURO.0079-21.2021. [PMID: 34330816 PMCID: PMC8387149 DOI: 10.1523/eneuro.0079-21.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 06/02/2021] [Accepted: 06/10/2021] [Indexed: 02/07/2023] Open
Abstract
Epilepsy is one of the most common neurologic disorders. Around one third of patients do not respond to current medications. This lack of treatment indicates a need for better understanding of the underlying mechanisms and, importantly, the identification of novel targets for drug manipulation. The fruit fly Drosophila melanogaster has a fast reproduction time, powerful genetics, and facilitates large sample sizes, making it a strong model of seizure mechanisms. To better understand behavioral and physiological phenotypes across major fly seizure genotypes we systematically measured seizure severity and secondary behavioral phenotypes at both the larval and adult stage. Comparison of several seizure-induction methods; specifically electrical, mechanical and heat induction, show that larval electroshock is the most effective at inducing seizures across a wide range of seizure-prone mutants tested. Locomotion in adults and larvae was found to be non-predictive of seizure susceptibility. Recording activity in identified larval motor neurons revealed variations in action potential (AP) patterns, across different genotypes, but these patterns did not correlate with seizure susceptibility. To conclude, while there is wide variation in mechanical induction, heat induction, and secondary phenotypes, electroshock is the most consistent method of seizure induction across known major seizure genotypes in Drosophila.
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12
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Pinto MJ, Tomé D, Almeida RD. The Ubiquitinated Axon: Local Control of Axon Development and Function by Ubiquitin. J Neurosci 2021; 41:2796-2813. [PMID: 33789876 PMCID: PMC8018891 DOI: 10.1523/jneurosci.2251-20.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 01/15/2021] [Accepted: 01/22/2021] [Indexed: 02/01/2023] Open
Abstract
Ubiquitin tagging sets protein fate. With a wide range of possible patterns and reversibility, ubiquitination can assume many shapes to meet specific demands of a particular cell across time and space. In neurons, unique cells with functionally distinct axons and dendrites harboring dynamic synapses, the ubiquitin code is exploited at the height of its power. Indeed, wide expression of ubiquitination and proteasome machinery at synapses, a diverse brain ubiquitome, and the existence of ubiquitin-related neurodevelopmental diseases support a fundamental role of ubiquitin signaling in the developing and mature brain. While special attention has been given to dendritic ubiquitin-dependent control, how axonal biology is governed by this small but versatile molecule has been considerably less discussed. Herein, we set out to explore the ubiquitin-mediated spatiotemporal control of an axon's lifetime: from its differentiation and growth through presynaptic formation, function, and pruning.
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Affiliation(s)
- Maria J Pinto
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, 3004-504, Portugal
| | - Diogo Tomé
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, 3004-504, Portugal
- Institute of Biomedicine, Department of Medical Sciences, University of Aveiro, Aveiro, 3810-193, Portugal
| | - Ramiro D Almeida
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, 3004-504, Portugal
- Institute of Biomedicine, Department of Medical Sciences, University of Aveiro, Aveiro, 3810-193, Portugal
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13
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Strutt H, Strutt D. How do the Fat-Dachsous and core planar polarity pathways act together and independently to coordinate polarized cell behaviours? Open Biol 2021; 11:200356. [PMID: 33561385 PMCID: PMC8061702 DOI: 10.1098/rsob.200356] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Planar polarity describes the coordinated polarization of cells within the plane of a tissue. This is controlled by two main pathways in Drosophila: the Frizzled-dependent core planar polarity pathway and the Fat–Dachsous pathway. Components of both of these pathways become asymmetrically localized within cells in response to long-range upstream cues, and form intercellular complexes that link polarity between neighbouring cells. This review examines if and when the two pathways are coupled, focusing on the Drosophila wing, eye and abdomen. There is strong evidence that the pathways are molecularly coupled in tissues that express a specific isoform of the core protein Prickle, namely Spiny-legs. However, in other contexts, the linkages between the pathways are indirect. We discuss how the two pathways act together and independently to mediate a diverse range of effects on polarization of cell structures and behaviours.
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Affiliation(s)
- Helen Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - David Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
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14
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Fernández-Pineda A, Monge-Asensio M, Rios M, Morey M. The Cytoplasmic LIM Domain Protein Espinas Contributes to Photoreceptor Layer Selection in the Visual System. BIOLOGY 2020; 9:E466. [PMID: 33327397 PMCID: PMC7764898 DOI: 10.3390/biology9120466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 12/12/2020] [Indexed: 11/22/2022]
Abstract
During circuit assembly it is essential that neurons connect with their specific synaptic partners. To facilitate this process, a common strategy in many organisms is the organization of brain regions, including the fly visual system, in layers and columns. The atypical-cadherin Flamingo (Fmi) and the receptor Golden Goal (Gogo) were proposed to regulate both the temporary and final layer selection of the R8 photoreceptor, through the cytoplasmic domain of Gogo. Our data suggests that Fmi intracellular signaling is also relevant for R8 final layer selection. The LIM-domain cytoplasmic molecule Espinas (Esn) binds Fmi, and they cooperatively control dendritic self-avoidance in sensory neurons. We observed defects in R8 layer selection in esn mutants with axons overshooting the final target layer, and we demonstrated that the LIM domain is necessary for layer selection. fmi knockdown in photoreceptors results in most R8 axons stalling at the temporary layer, however, we also detected R8 axons projecting past the final-target layer, and showed that fmi and esn genetically interact. Based on the previously described physical and genetic interactions between Fmi/Esn and the findings presented here, we propose that Esn signals downstream of Fmi to stabilize R8 axons in their final target layer.
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Affiliation(s)
- Alejandra Fernández-Pineda
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (A.F.-P.); (M.M.-A.); (M.R.)
- Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain
| | - Martí Monge-Asensio
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (A.F.-P.); (M.M.-A.); (M.R.)
- Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain
| | - Martín Rios
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (A.F.-P.); (M.M.-A.); (M.R.)
| | - Marta Morey
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (A.F.-P.); (M.M.-A.); (M.R.)
- Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain
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15
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Guo D, Ru J, Mao F, Ouyang H, Ju R, Wu K, Liu Y, Liu C. Ontogenesis of the tear drainage system requires Prickle1-driven polarized basement membrane deposition. Development 2020; 147:dev.191726. [PMID: 33144400 DOI: 10.1242/dev.191726] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 10/23/2020] [Indexed: 12/13/2022]
Abstract
In terrestrial animals, the lacrimal drainage apparatus evolved to serve as conduits for tear flow; however, little is known about the ontogenesis of this system. Here, we define the anatomy of the fully formed tear duct in mice, characterize crucial morphogenetic events for the development of tear duct components and identify the site for primordial tear duct (PTD) initiation. We report that the PTD originates from the orbital lacrimal lamina, a junction formed by the epithelia of the maxillary and lateral nasal processes. We demonstrate that Prickle1, a key component of planar cell polarity signaling, is expressed in progenitors of the PTD and throughout tear duct morphogenesis. Disruption of Prickle1 stalls tear duct elongation; in particular, the loss of basement membrane deposition and aberrant cytoplasmic accumulation of laminin are salient. Altered cell adhesion, cytoskeletal transport systems, vesicular transport systems and cell axis orientation in Prickle1 mutants support the role of Prickle1 in planar cell polarity. Taken together, our results highlight a crucial role of Prickle1-mediated polarized basement membrane secretion and deposition in PTD elongation.
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Affiliation(s)
- Dianlei Guo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Jiali Ru
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Fuxiang Mao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Hong Ouyang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Rong Ju
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Kaili Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Chunqiao Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
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16
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Sun F, Jiang F, Zhang N, Li H, Tian W, Liu W. Upregulation of Prickle2 Ameliorates Alzheimer's Disease-Like Pathology in a Transgenic Mouse Model of Alzheimer's Disease. Front Cell Dev Biol 2020; 8:565020. [PMID: 33015060 PMCID: PMC7509431 DOI: 10.3389/fcell.2020.565020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/25/2020] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder that has no effective therapies. Prickle planar cell polarity protein 2 (Prickle2), is an important cytoplasmic regulator of Wnt/PCP signaling. It has been reported that Prickle2 deficiency reduced neurite outgrowth levels in mouse N2a cells and led to autism-like behaviors and hippocampal synaptic dysfunction in mice. However, much less is known about the relationship of Prickle2 to AD pathogenesis. RT-qPCR, Western blot and IHC results showed that the mRNA and protein levels of Prickle2 were reduced in APP/PS1/Tau transgenic (3xTg) mice. Intravenous injection of Prickle2-overexpressing AAV-PHP.eB vectors improved the cognitive deficits in 3xTg mice. We also demonstrated that Prickle2 could repress oxidative stress and neuroinflammation, ameliorate the amyloid β (Aβ) plaque pathology and reduce Tau hyperphosphorylation in APP/PS1 mice. Further investigation of the mechanism of Prickle2 in AD revealed that Prickle2 inhibited Wnt/PCP/JNK pathway in vivo and in vitro. Our results suggest that Prickle2 might be a potential candidate for the diagnosis and treatment of AD.
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Affiliation(s)
- Fengxian Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Fang Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Na Zhang
- Department of Cardiology, Tianjin Medical University General Hospital, Tianjin, China
| | - Hua Li
- Clinical College of Ophthalmology, Tianjin Eye Hospital, Tianjin Medical University, Tianjin, China
| | - Weiping Tian
- Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Weiying Liu
- Department of Pathogen Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
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17
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Takai A, Yamaguchi M, Yoshida H, Chiyonobu T. Investigating Developmental and Epileptic Encephalopathy Using Drosophila melanogaster. Int J Mol Sci 2020; 21:ijms21176442. [PMID: 32899411 PMCID: PMC7503973 DOI: 10.3390/ijms21176442] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 08/30/2020] [Accepted: 09/01/2020] [Indexed: 12/16/2022] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are the spectrum of severe epilepsies characterized by early-onset, refractory seizures occurring in the context of developmental regression or plateauing. Early infantile epileptic encephalopathy (EIEE) is one of the earliest forms of DEE, manifesting as frequent epileptic spasms and characteristic electroencephalogram findings in early infancy. In recent years, next-generation sequencing approaches have identified a number of monogenic determinants underlying DEE. In the case of EIEE, 85 genes have been registered in Online Mendelian Inheritance in Man as causative genes. Model organisms are indispensable tools for understanding the in vivo roles of the newly identified causative genes. In this review, we first present an overview of epilepsy and its genetic etiology, especially focusing on EIEE and then briefly summarize epilepsy research using animal and patient-derived induced pluripotent stem cell (iPSC) models. The Drosophila model, which is characterized by easy gene manipulation, a short generation time, low cost and fewer ethical restrictions when designing experiments, is optimal for understanding the genetics of DEE. We therefore highlight studies with Drosophila models for EIEE and discuss the future development of their practical use.
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Affiliation(s)
- Akari Takai
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
| | - Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 603-8585, Japan; (M.Y.); (H.Y.)
- Kansai Gakken Laboratory, Kankyo Eisei Yakuhin Co. Ltd., Kyoto 619-0237, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 603-8585, Japan; (M.Y.); (H.Y.)
| | - Tomohiro Chiyonobu
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
- Correspondence:
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18
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Yu J, Liang X, Ji Y, Ai C, Liu J, Zhu L, Nie Z, Jin X, Wang C, Zhang J, Zhao F, Mei S, Zhao X, Zhou X, Zhang M, Wang M, Huang T, Jiang P, Guan MX. PRICKLE3 linked to ATPase biogenesis manifested Leber's hereditary optic neuropathy. J Clin Invest 2020; 130:4935-4946. [PMID: 32516135 PMCID: PMC7456240 DOI: 10.1172/jci134965] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 06/04/2020] [Indexed: 12/16/2022] Open
Abstract
Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease. X-linked nuclear modifiers were proposed to modify the phenotypic manifestation of LHON-associated mitochondrial DNA (mtDNA) mutations. By whole-exome sequencing, we identified the X-linked LHON modifier (c.157C>T, p.Arg53Trp) in PRICKLE3 encoding a mitochondrial protein linked to biogenesis of ATPase in 3 Chinese families. All affected individuals carried both ND4 11778G>A and p.Arg53Trp mutations, while subjects bearing only a single mutation exhibited normal vision. The cells carrying the p.Arg53Trp mutation exhibited defective assembly, stability, and function of ATP synthase, verified by PRICKLE3-knockdown cells. Coimmunoprecipitation indicated the direct interaction of PRICKLE3 with ATP synthase via ATP8. Strikingly, cells bearing both p.Arg53Trp and m.11778G>A mutations displayed greater mitochondrial dysfunction than those carrying only a single mutation. This finding indicated that the p.Arg53Trp mutation acted in synergy with the m.11778G>A mutation and deteriorated mitochondrial dysfunctions necessary for the expression of LHON. Furthermore, we demonstrated that Prickle3-deficient mice exhibited pronounced ATPase deficiencies. Prickle3-knockout mice recapitulated LHON phenotypes with retinal deficiencies, including degeneration of retinal ganglion cells and abnormal vasculature. Our findings provided new insights into the pathophysiology of LHON that were manifested by interaction between mtDNA mutations and X-linked nuclear modifiers.
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Affiliation(s)
- Jialing Yu
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, Hangzhou, China
| | - Xiaoyang Liang
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Yanchun Ji
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Cheng Ai
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Junxia Liu
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Ling Zhu
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhipeng Nie
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaofen Jin
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, Hangzhou, China
| | - Chenghui Wang
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Juanjuan Zhang
- Institute of Genetics and
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Fuxin Zhao
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Shuang Mei
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaoxu Zhao
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiangtian Zhou
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Minglian Zhang
- Department of Ophthalmology, Hebei Provincial Eye Hospital, Xingtai, China
| | - Meng Wang
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Pingping Jiang
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Institute of Genetics and
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Reproductive Genetics, Ministry of Education, Hangzhou, China
- Joint Institute of Genetics and Genomic Medicine, Zhejiang University and University of Toronto, Zhejiang University, Hangzhou, China
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19
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Cho B, Song S, Axelrod JD. Prickle isoforms determine handedness of helical morphogenesis. eLife 2020; 9:51456. [PMID: 31934858 PMCID: PMC7004564 DOI: 10.7554/elife.51456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 01/10/2020] [Indexed: 12/17/2022] Open
Abstract
Subcellular asymmetry directed by the planar cell polarity (PCP) signaling pathway orients numerous morphogenetic events in both invertebrates and vertebrates. Here, we describe a morphogenetic movement in which the intertwined socket and shaft cells of the Drosophila anterior wing margin mechanosensory bristles undergo PCP-directed apical rotation, inducing twisting that results in a helical structure of defined chirality. We show that the Frizzled/Vang PCP signaling module coordinates polarity among and between bristles and surrounding cells to direct this rotation. Furthermore, we show that dynamic interplay between two isoforms of the Prickle protein determines right- or left-handed bristle morphogenesis. We provide evidence that, Frizzled/Vang signaling couples to the Fat/Dachsous PCP directional signal in opposite directions depending on whether Pkpk or Pksple predominates. Dynamic interplay between Pk isoforms is likely to be an important determinant of PCP outcomes in diverse contexts. Similar mechanisms may orient other lateralizing morphogenetic processes.
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Affiliation(s)
- Bomsoo Cho
- Department of Pathology, Stanford University School of Medicine, Stanford, United States
| | - Song Song
- Department of Pathology, Stanford University School of Medicine, Stanford, United States
| | - Jeffrey D Axelrod
- Department of Pathology, Stanford University School of Medicine, Stanford, United States
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20
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Kasuya J, Iyengar A, Chen HL, Lansdon P, Wu CF, Kitamoto T. Milk-whey diet substantially suppresses seizure-like phenotypes of paraShu, a Drosophila voltage-gated sodium channel mutant. J Neurogenet 2019; 33:164-178. [PMID: 31096839 DOI: 10.1080/01677063.2019.1597082] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The Drosophila mutant paraShu harbors a dominant, gain-of-function allele of the voltage-gated sodium channel gene, paralytic (para). The mutant flies display severe seizure-like phenotypes, including neuronal hyperexcitability, spontaneous spasms, ether-induced leg shaking, and heat-induced convulsions. We unexpectedly found that two distinct food recipes used routinely in the Drosophila research community result in a striking difference in severity of the paraShu phenotypes. Namely, when paraShu mutants were raised on the diet originally formulated by Edward Lewis in 1960, they showed severe neurological defects as previously reported. In contrast, when they were raised on the diet developed by Frankel and Brousseau in 1968, these phenotypes were substantially suppressed. Comparison of the effects of these two well-established food recipes revealed that the diet-dependent phenotypic suppression is accounted for by milk whey, which is present only in the latter. Inclusion of milk whey in the diet during larval stages was critical for suppression of the adult paraShu phenotypes, suggesting that this dietary modification affects development of the nervous system. We also found that milk whey has selective effects on other neurological mutants. Among the behavioral phenotypes of different para mutant alleles, those of paraGEFS+ and parabss were suppressed by milk whey, while those of paraDS and parats1 were not significantly affected. Overall, our study demonstrates that different diets routinely used in Drosophila labs could have considerably different effects on neurological phenotypes of Drosophila mutants. This finding provides a solid foundation for further investigation into how dietary modifications affect development and function of the nervous system and, ultimately, how they influence behavior.
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Affiliation(s)
- Junko Kasuya
- a Department of Anesthesia, Carver College of Medicine , University of Iowa , Iowa city , IA , USA
| | - Atulya Iyengar
- b Department of Biology, College of Liberal Arts and Sciences , University of Iowa , Iowa city , IA , USA.,c Interdisciplinary Graduate Program in Neuroscience , University of Iowa , Iowa city , IA , USA
| | - Hung-Lin Chen
- d Department of Medical Research , Tung's Taichung MetroHarbor Hospital , Taichung , Taiwan 43503 , ROC
| | - Patrick Lansdon
- e Interdisciplinary Graduate Program in Genetics , University of Iowa , Iowa city , IA , USA
| | - Chun-Fang Wu
- b Department of Biology, College of Liberal Arts and Sciences , University of Iowa , Iowa city , IA , USA.,c Interdisciplinary Graduate Program in Neuroscience , University of Iowa , Iowa city , IA , USA.,e Interdisciplinary Graduate Program in Genetics , University of Iowa , Iowa city , IA , USA
| | - Toshihiro Kitamoto
- a Department of Anesthesia, Carver College of Medicine , University of Iowa , Iowa city , IA , USA.,c Interdisciplinary Graduate Program in Neuroscience , University of Iowa , Iowa city , IA , USA.,e Interdisciplinary Graduate Program in Genetics , University of Iowa , Iowa city , IA , USA
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21
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Lee J, Iyengar A, Wu CF. Distinctions among electroconvulsion- and proconvulsant-induced seizure discharges and native motor patterns during flight and grooming: quantitative spike pattern analysis in Drosophila flight muscles. J Neurogenet 2019; 33:125-142. [PMID: 30982417 DOI: 10.1080/01677063.2019.1581188] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In Drosophila, high-frequency electrical stimulation across the brain triggers a highly stereotypic repertoire of spasms. These electroconvulsive seizures (ECS) manifest as distinctive spiking discharges across the nervous system and can be stably assessed throughout the seizure repertoire in the large indirect flight muscles dorsal longitudinal muscles (DLMs) to characterize modifications in seizure-prone mutants. However, the relationships between ECS-spike patterns and native motor programs, including flight and grooming, are not known and their similarities and distinctions remain to be characterized. We employed quantitative spike pattern analyses for the three motor patterns including: (1) overall firing frequency, (2) spike timing between contralateral fibers, and (3) short-term variability in spike interval regularity (CV2) and instantaneous firing frequency (ISI-1). This base-line information from wild-type (WT) flies facilitated quantitative characterization of mutational effects of major neurotransmitter systems: excitatory cholinergic (Cha), inhibitory GABAergic (Rdl) and electrical (ShakB) synaptic transmission. The results provide an initial glimpse on the vulnerability of individual motor patterns to different perturbations. We found marked alterations of ECS discharge spike patterns in terms of either seizure threshold, spike frequency or spiking regularity. In contrast, no gross alterations during grooming and a small but noticeable reduction of firing frequency during Rdl mutant flight were found, suggesting a role for GABAergic modulation of flight motor programs. Picrotoxin (PTX), a known pro-convulsant that inhibits GABAA receptors, induced DLM spike patterns that displayed some features, e.g. left-right coordination and ISI-1 range, that could be found in flight or grooming, but distinct from ECS discharges. These quantitative techniques may be employed to reveal overlooked relationships among aberrant motor patterns as well as their links to native motor programs.
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Affiliation(s)
- Jisue Lee
- a Department of Biology , University of Iowa , Iowa City , IA , USA
| | - Atulya Iyengar
- a Department of Biology , University of Iowa , Iowa City , IA , USA.,b Interdisiplinary Graduate Program in Neuroscience , University of Iowa , Iowa City , IA , USA
| | - Chun-Fang Wu
- a Department of Biology , University of Iowa , Iowa City , IA , USA.,b Interdisiplinary Graduate Program in Neuroscience , University of Iowa , Iowa City , IA , USA
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22
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Mitotic Motor KIFC1 Is an Organizer of Microtubules in the Axon. J Neurosci 2019; 39:3792-3811. [PMID: 30804089 DOI: 10.1523/jneurosci.3099-18.2019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/30/2019] [Accepted: 02/18/2019] [Indexed: 11/21/2022] Open
Abstract
KIFC1 (also called HSET or kinesin-14a) is best known as a multifunctional motor protein essential for mitosis. The present studies are the first to explore KIFC1 in terminally postmitotic neurons. Using RNA interference to partially deplete KIFC1 from rat neurons (from animals of either gender) in culture, pharmacologic agents that inhibit KIFC1, and expression of mutant KIFC1 constructs, we demonstrate critical roles for KIFC1 in regulating axonal growth and retraction as well as growth cone morphology. Experimental manipulations of KIFC1 elicit morphological changes in the axon as well as changes in the organization, distribution, and polarity orientation of its microtubules. Together, the results indicate a mechanism by which KIFC1 binds to microtubules in the axon and slides them into alignment in an ATP-dependent fashion and then cross-links them in an ATP-independent fashion to oppose their subsequent sliding by other motors.SIGNIFICANCE STATEMENT Here, we establish that KIFC1, a molecular motor well characterized in mitosis, is robustly expressed in neurons, where it has profound influence on the organization of microtubules in a number of different functional contexts. KIFC1 may help answer long-standing questions in cellular neuroscience such as, mechanistically, how growth cones stall and how axonal microtubules resist forces that would otherwise cause the axon to retract. Knowledge about KIFC1 may help researchers to devise strategies for treating disorders of the nervous system involving axonal retraction given that KIFC1 is expressed in adult neurons as well as developing neurons.
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23
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Mastrangelo M, Tolve M, Martinelli M, Di Noia SP, Parrini E, Leuzzi V. PRICKLE1
-related early onset epileptic encephalopathy. Am J Med Genet A 2018; 176:2841-2845. [DOI: 10.1002/ajmg.a.40625] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 08/08/2018] [Accepted: 08/13/2018] [Indexed: 01/05/2023]
Affiliation(s)
- Mario Mastrangelo
- Department of Human Neuroscience; “Sapienza, University of Rome”; Rome Italy
| | - Manuela Tolve
- Department of Experimental Medicine; “Sapienza, University of Rome”; Rome Italy
| | - Martina Martinelli
- Department of Human Neuroscience; “Sapienza, University of Rome”; Rome Italy
| | - Sofia P. Di Noia
- Department of Human Neuroscience; “Sapienza, University of Rome”; Rome Italy
| | - Elena Parrini
- Neuroscience and Neurogenetics Department; Meyer Children’s Hospital, University of Florence; Florence Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience; “Sapienza, University of Rome”; Rome Italy
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24
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Eidhof I, Baets J, Kamsteeg EJ, Deconinck T, van Ninhuijs L, Martin JJ, Schüle R, Züchner S, De Jonghe P, Schenck A, van de Warrenburg BP. GDAP2 mutations implicate susceptibility to cellular stress in a new form of cerebellar ataxia. Brain 2018; 141:2592-2604. [PMID: 30084953 PMCID: PMC7534050 DOI: 10.1093/brain/awy198] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/09/2018] [Accepted: 06/11/2018] [Indexed: 12/18/2022] Open
Abstract
Autosomal recessive cerebellar ataxias are a group of rare disorders that share progressive degeneration of the cerebellum and associated tracts as the main hallmark. Here, we report two unrelated patients with a new subtype of autosomal recessive cerebellar ataxia caused by biallelic, gene-disruptive mutations in GDAP2, a gene previously not implicated in disease. Both patients had onset of ataxia in the fourth decade. Other features included progressive spasticity and dementia. Neuropathological examination showed degenerative changes in the cerebellum, olive inferior, thalamus, substantia nigra, and pyramidal tracts, as well as tau pathology in the hippocampus and amygdala. To provide further evidence for a causative role of GDAP2 mutations in autosomal recessive cerebellar ataxia pathophysiology, its orthologous gene was investigated in the fruit fly Drosophila melanogaster. Ubiquitous knockdown of Drosophila Gdap2 resulted in shortened lifespan and motor behaviour anomalies such as righting defects, reduced and uncoordinated walking behaviour, and compromised flight. Gdap2 expression levels responded to stress treatments in control flies, and Gdap2 knockdown flies showed increased sensitivity to deleterious effects of stressors such as reactive oxygen species and nutrient deprivation. Thus, Gdap2 knockdown in Drosophila and GDAP2 loss-of-function mutations in humans lead to locomotor phenotypes, which may be mediated by altered responses to cellular stress.
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Affiliation(s)
- Ilse Eidhof
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Centre, GA Nijmegen, The Netherlands
| | - Jonathan Baets
- Neurogenetics Group, Center for Molecular Neurology, VIB, Antwerp, Belgium
- Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
- Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Centre, GA Nijmegen, The Netherlands
| | - Tine Deconinck
- Neurogenetics Group, Center for Molecular Neurology, VIB, Antwerp, Belgium
- Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Lisa van Ninhuijs
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Centre, GA Nijmegen, The Netherlands
| | | | - Rebecca Schüle
- Department of Neurodegenerative Diseases, Hertie-Institute for Clinical Brain Research and Center of Neurology, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Stephan Züchner
- Dr. John T. Macdonald Foundation, Department of Human Genetics, Miami, USA
- John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, USA
| | - Peter De Jonghe
- Neurogenetics Group, Center for Molecular Neurology, VIB, Antwerp, Belgium
- Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
- Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Annette Schenck
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Centre, GA Nijmegen, The Netherlands
| | - Bart P van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Centre, GC Nijmegen, The Netherlands
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25
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Todd BP, Bassuk AG. A de novo mutation in PRICKLE1 associated with myoclonic epilepsy and autism spectrum disorder. J Neurogenet 2018; 32:313-315. [PMID: 29790814 DOI: 10.1080/01677063.2018.1473862] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Homozygous recessive mutations in the PRICKLE1 gene were first described in three consanguineous families with myoclonic epilepsy. Subsequent studies have identified neurological abnormalities in humans and animal models with both heterozygous and homozygous mutations in PRICKLE1 orthologs. We describe a 7-year-old with a novel de novo missense mutation in PRICKLE1 associated with epilepsy, autism spectrum disorder and global developmental delay.
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Affiliation(s)
- Brittany P Todd
- a Department of Pediatrics , The University of Iowa , Iowa City , United States
| | - Alexander G Bassuk
- a Department of Pediatrics , The University of Iowa , Iowa City , United States
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26
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Prickle is phosphorylated by Nemo and targeted for degradation to maintain Prickle/Spiny-legs isoform balance during planar cell polarity establishment. PLoS Genet 2018; 14:e1007391. [PMID: 29758044 PMCID: PMC5967807 DOI: 10.1371/journal.pgen.1007391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 05/24/2018] [Accepted: 05/02/2018] [Indexed: 11/19/2022] Open
Abstract
Planar cell polarity (PCP) instructs tissue patterning in a wide range of organisms from fruit flies to humans. PCP signaling coordinates cell behavior across tissues and is integrated by cells to couple cell fate identity with position in a developing tissue. In the fly eye, PCP signaling is required for the specification of R3 and R4 photoreceptors based upon their positioning relative to the dorso-ventral axis. The ‘core’ PCP pathway involves the asymmetric localization of two distinct membrane-bound complexes, one containing Frizzled (Fz, required in R3) and the other Van Gogh (Vang, required in R4). Inhibitory interactions between the cytosolic components of each complex reinforce asymmetric localization. Prickle (Pk) and Spiny-legs (Pk-Sple) are two antagonistic isoforms of the prickle (pk) gene and are cytoplasmic components of the Vang complex. The balance between their levels is critical for tissue patterning, with Pk-Sple being the major functional isoform in the eye. Here we uncover a post-translational role for Nemo kinase in limiting the amount of the minor isoform Pk. We identified Pk as a Nemo substrate in a genome-wide in vitro band-shift screen. In vivo, nemo genetically interacts with pkpk but not pksple and enhances PCP defects in the eye and leg. Nemo phosphorylation limits Pk levels and is required specifically in the R4 photoreceptor like the major isoform, Pk-Sple. Genetic interaction and biochemical data suggest that Nemo phosphorylation of Pk leads to its proteasomal degradation via the Cullin1/SkpA/Slmb complex. dTAK and Homeodomain interacting protein kinase (Hipk) may also act together with Nemo to target Pk for degradation, consistent with similar observations in mammalian studies. Our results therefore demonstrate a mechanism to maintain low levels of the minor Pk isoform, allowing PCP complexes to form correctly and specify cell fate. For functional tissues to form, individual cells must correctly orient themselves and function appropriately for their particular location in the body. The Planar Cell Polarity (PCP) complexes transmit one set of spatial cues by acting as signposts to mark direction across an epithelial layer. PCP signals can direct and coordinate cell differentiation, the behavior of groups of cells, or the orientation of individual cellular protrusions, depending on the tissue. PCP signals act as a polarization relay with two different complexes being positioned on opposite sides of each cell. This pattern of polarity is transmitted to neighboring cells and so extends across the tissue. In the fly eye, PCP signals control the differentiation of a pair of photoreceptors, R3 and R4, where the cell that is positioned closer to the dorso-ventral midline becomes R3. An excess of the PCP protein Prickle prevents the proper assembly of PCP complexes in the eye and so alters R3/R4 fate. Here we show that Nemo kinase is required in the R4 cell to phosphorylate Prickle and promote its degradation by the proteasome. Maintenance of low Prickle levels allows proper formation of PCP complexes, cell fate specification, and eye development.
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27
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Saito Y, Desai RR, Muthuswamy SK. Reinterpreting polarity and cancer: The changing landscape from tumor suppression to tumor promotion. Biochim Biophys Acta Rev Cancer 2018; 1869:103-116. [DOI: 10.1016/j.bbcan.2017.12.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/21/2022]
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28
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Farhan SMK, Nixon KCJ, Everest M, Edwards TN, Long S, Segal D, Knip MJ, Arts HH, Chakrabarti R, Wang J, Robinson JF, Lee D, Mirsattari SM, Rupar CA, Siu VM, Poulter MO, Hegele RA, Kramer JM. Identification of a novel synaptic protein, TMTC3, involved in periventricular nodular heterotopia with intellectual disability and epilepsy. Hum Mol Genet 2018; 26:4278-4289. [PMID: 28973161 PMCID: PMC5886076 DOI: 10.1093/hmg/ddx316] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/08/2017] [Indexed: 12/30/2022] Open
Abstract
Defects in neuronal migration cause brain malformations, which are associated with intellectual disability (ID) and epilepsy. Using exome sequencing, we identified compound heterozygous variants (p.Arg71His and p. Leu729ThrfsTer6) in TMTC3, encoding transmembrane and tetratricopeptide repeat containing 3, in four siblings with nocturnal seizures and ID. Three of the four siblings have periventricular nodular heterotopia (PVNH), a common brain malformation caused by failure of neurons to migrate from the ventricular zone to the cortex. Expression analysis using patient-derived cells confirmed reduced TMTC3 transcript levels and loss of the TMTC3 protein compared to parental and control cells. As TMTC3 function is currently unexplored in the brain, we gathered support for a neurobiological role for TMTC3 by generating flies with post-mitotic neuron-specific knockdown of the highly conserved Drosophila melanogaster TMTC3 ortholog, CG4050/tmtc3. Neuron-specific knockdown of tmtc3 in flies resulted in increased susceptibility to induced seizures. Importantly, this phenotype was rescued by neuron-specific expression of human TMTC3, suggesting a role for TMTC3 in seizure biology. In addition, we observed co-localization of TMTC3 in the rat brain with vesicular GABA transporter (VGAT), a presynaptic marker for inhibitory synapses. TMTC3 is localized at VGAT positive pre-synaptic terminals and boutons in the rat hypothalamus and piriform cortex, suggesting a role for TMTC3 in the regulation of GABAergic inhibitory synapses. TMTC3 did not co-localize with Vglut2, a presynaptic marker for excitatory neurons. Our data identified TMTC3 as a synaptic protein that is involved in PVNH with ID and epilepsy, in addition to its previously described association with cobblestone lissencephaly.
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Affiliation(s)
- Sali M K Farhan
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7.,Department of Biochemistry
| | - Kevin C J Nixon
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Michelle Everest
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Tara N Edwards
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Shirley Long
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Dmitri Segal
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Maria J Knip
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Heleen H Arts
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7.,Division of Genetics and Development, Children's Health Research Institute, London, ON, Canada, N6A 5W9.,Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre Nijmegen, The Netherlands
| | - Rana Chakrabarti
- Division of Genetics and Development, Children's Health Research Institute, London, ON, Canada, N6A 5W9.,Department of Pediatrics
| | - Jian Wang
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7
| | - John F Robinson
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7
| | | | - Seyed M Mirsattari
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1.,Departments of Clinical Neurological Sciences, Medical Biophysics, Medical Imaging and Psychology
| | - C Anthony Rupar
- Department of Biochemistry.,Division of Genetics and Development, Children's Health Research Institute, London, ON, Canada, N6A 5W9.,Department of Pediatrics.,Department of Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Victoria M Siu
- Department of Biochemistry.,Division of Genetics and Development, Children's Health Research Institute, London, ON, Canada, N6A 5W9.,Department of Pediatrics
| | | | - Michael O Poulter
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Robert A Hegele
- Molecular Medicine Research Group, Robarts Research Institute, London, ON, Canada, N6A 5B7.,Department of Biochemistry
| | - Jamie M Kramer
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1.,Division of Genetics and Development, Children's Health Research Institute, London, ON, Canada, N6A 5W9.,Department of Biology, Faculty of Science, Western University, London, ON, Canada, N6A 5B7
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29
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Kunimoto K, Bayly RD, Vladar EK, Vonderfecht T, Gallagher AR, Axelrod JD. Disruption of Core Planar Cell Polarity Signaling Regulates Renal Tubule Morphogenesis but Is Not Cystogenic. Curr Biol 2017; 27:3120-3131.e4. [PMID: 29033332 DOI: 10.1016/j.cub.2017.09.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/23/2017] [Accepted: 09/07/2017] [Indexed: 12/22/2022]
Abstract
Oriented cell division (OCD) and convergent extension (CE) shape developing renal tubules, and their disruption has been associated with polycystic kidney disease (PKD) genes, the majority of which encode proteins that localize to primary cilia. Core planar cell polarity (PCP) signaling controls OCD and CE in other contexts, leading to the hypothesis that disruption of PCP signaling interferes with CE and/or OCD to produce PKD. Nonetheless, the contribution of PCP to tubulogenesis and cystogenesis is uncertain, and two major questions remain unanswered. Specifically, the inference that mutation of PKD genes interferes with PCP signaling is untested, and the importance of PCP signaling for cystogenic PKD phenotypes has not been examined. We show that, during proliferative stages, PCP signaling polarizes renal tubules to control OCD. However, we find that, contrary to the prevailing model, PKD mutations do not disrupt PCP signaling but instead act independently and in parallel with PCP signaling to affect OCD. Indeed, PCP signaling that is normally downregulated once development is completed is retained in cystic adult kidneys. Disrupting PCP signaling results in inaccurate control of tubule diameter, a tightly regulated parameter with important physiological ramifications. However, we show that disruption of PCP signaling is not cystogenic. Our results suggest that regulating tubule diameter is a key function of PCP signaling but that loss of this control does not induce cysts.
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Affiliation(s)
- Koshi Kunimoto
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA
| | - Roy D Bayly
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA
| | - Eszter K Vladar
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA
| | - Tyson Vonderfecht
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA
| | - Anna-Rachel Gallagher
- Department of Internal Medicine, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Jeffrey D Axelrod
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA.
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30
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Praschberger R, Lowe SA, Malintan NT, Giachello CNG, Patel N, Houlden H, Kullmann DM, Baines RA, Usowicz MM, Krishnakumar SS, Hodge JJL, Rothman JE, Jepson JEC. Mutations in Membrin/GOSR2 Reveal Stringent Secretory Pathway Demands of Dendritic Growth and Synaptic Integrity. Cell Rep 2017; 21:97-109. [PMID: 28978487 PMCID: PMC5640804 DOI: 10.1016/j.celrep.2017.09.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/17/2017] [Accepted: 09/01/2017] [Indexed: 11/16/2022] Open
Abstract
Mutations in the Golgi SNARE (SNAP [soluble NSF attachment protein] receptor) protein Membrin (encoded by the GOSR2 gene) cause progressive myoclonus epilepsy (PME). Membrin is a ubiquitous and essential protein mediating ER-to-Golgi membrane fusion. Thus, it is unclear how mutations in Membrin result in a disorder restricted to the nervous system. Here, we use a multi-layered strategy to elucidate the consequences of Membrin mutations from protein to neuron. We show that the pathogenic mutations cause partial reductions in SNARE-mediated membrane fusion. Importantly, these alterations were sufficient to profoundly impair dendritic growth in Drosophila models of GOSR2-PME. Furthermore, we show that Membrin mutations cause fragmentation of the presynaptic cytoskeleton coupled with transsynaptic instability and hyperactive neurotransmission. Our study highlights how dendritic growth is vulnerable even to subtle secretory pathway deficits, uncovers a role for Membrin in synaptic function, and provides a comprehensive explanatory basis for genotype-phenotype relationships in GOSR2-PME.
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Affiliation(s)
- Roman Praschberger
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Simon A Lowe
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Nancy T Malintan
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Carlo N G Giachello
- Faculty of Biology, Medicine, and Health, Division of Neuroscience & Experimental Psychology, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Nian Patel
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Henry Houlden
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | - Dimitri M Kullmann
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Richard A Baines
- Faculty of Biology, Medicine, and Health, Division of Neuroscience & Experimental Psychology, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Maria M Usowicz
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Shyam S Krishnakumar
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - James J L Hodge
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - James E Rothman
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - James E C Jepson
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK.
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31
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Raju PK, Satishchandra P, Nayak S, Iyer V, Sinha S, Anand A. Microtubule-associated defects caused by EFHC1
mutations in juvenile myoclonic epilepsy. Hum Mutat 2017; 38:816-826. [DOI: 10.1002/humu.23221] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 01/06/2023]
Affiliation(s)
- Praveen K Raju
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research; Jakkur Bangalore Karnataka India
| | | | - Sourav Nayak
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research; Jakkur Bangalore Karnataka India
| | - Vishwanathan Iyer
- Department of Neurology; National Institute of Mental Health and Neurosciences; Bangalore Karnataka India
| | - Sanjib Sinha
- Department of Neurology; National Institute of Mental Health and Neurosciences; Bangalore Karnataka India
| | - Anuranjan Anand
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research; Jakkur Bangalore Karnataka India
- Neuroscience Unit; Jawaharlal Nehru Centre for Advanced Scientific Research; Jakkur Bangalore Karnataka India
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32
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Balestrini S, Sisodiya SM. Pharmacogenomics in epilepsy. Neurosci Lett 2017; 667:27-39. [PMID: 28082152 PMCID: PMC5846849 DOI: 10.1016/j.neulet.2017.01.014] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 12/12/2022]
Abstract
Genetic variation can influence response to antiepileptic drug (AED) treatment through various effector processes. Metabolism of many AEDs is mediated by the cytochrome P450 (CYP) family; some of the CYPs have allelic variants that may affect serum AED concentrations. ‘Precision medicine’ focuses on the identification of an underlying genetic aetiology allowing personalised therapeutic choices. Certain human leukocyte antigen, HLA, alleles are associated with an increased risk of idiosyncratic adverse drug reactions. New results are emerging from large-scale multinational efforts, likely imminently to add knowledge of value from a pharmacogenetic perspective.
There is high variability in the response to antiepileptic treatment across people with epilepsy. Genetic factors significantly contribute to such variability. Recent advances in the genetics and neurobiology of the epilepsies are establishing the basis for a new era in the treatment of epilepsy, focused on each individual and their specific epilepsy. Variation in response to antiepileptic drug treatment may arise from genetic variation in a range of gene categories, including genes affecting drug pharmacokinetics, and drug pharmacodynamics, but also genes held to actually cause the epilepsy itself. From a purely pharmacogenetic perspective, there are few robust genetic findings with established evidence in epilepsy. Many findings are still controversial with anecdotal or less secure evidence and need further validation, e.g. variation in genes for transporter systems and antiepileptic drug targets. The increasing use of genetic sequencing and the results of large-scale collaborative projects may soon expand the established evidence. Precision medicine treatments represent a growing area of interest, focussing on reversing or circumventing the pathophysiological effects of specific gene mutations. This could lead to a dramatic improvement of the effectiveness and safety of epilepsy treatments, by targeting the biological mechanisms responsible for epilepsy in each specific individual. Whilst much has been written about epilepsy pharmacogenetics, there does now seem to be building momentum that promises to deliver results of use in clinic.
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Affiliation(s)
- Simona Balestrini
- NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, and Epilepsy Society, Chalfont-St-Peter, Bucks, United Kingdom; Neuroscience Department, Polytechnic University of Marche, Ancona, Italy
| | - Sanjay M Sisodiya
- NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, and Epilepsy Society, Chalfont-St-Peter, Bucks, United Kingdom.
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33
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Lam AK, Phillips BT. Wnt Signaling Polarizes C. elegans Asymmetric Cell Divisions During Development. Results Probl Cell Differ 2017; 61:83-114. [PMID: 28409301 PMCID: PMC6057142 DOI: 10.1007/978-3-319-53150-2_4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Asymmetric cell division is a common mode of cell differentiation during the invariant lineage of the nematode, C. elegans. Beginning at the four-cell stage, and continuing throughout embryogenesis and larval development, mother cells are polarized by Wnt ligands, causing an asymmetric inheritance of key members of a Wnt/β-catenin signal transduction pathway termed the Wnt/β-catenin asymmetry pathway. The resulting daughter cells are distinct at birth with one daughter cell activating Wnt target gene expression via β-catenin activation of TCF, while the other daughter displays transcriptional repression of these target genes. Here, we seek to review the body of evidence underlying a unified model for Wnt-driven asymmetric cell division in C. elegans, identify global themes that occur during asymmetric cell division, as well as highlight tissue-specific variations. We also discuss outstanding questions that remain unanswered regarding this intriguing mode of asymmetric cell division.
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Affiliation(s)
- Arielle Koonyee Lam
- Interdisciplinary Graduate Program in Molecular and Cellular Biology, University of Iowa, Iowa City, IA, USA
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34
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Lithium-Responsive Seizure-Like Hyperexcitability Is Caused by a Mutation in the Drosophila Voltage-Gated Sodium Channel Gene paralytic. eNeuro 2016; 3:eN-NWR-0221-16. [PMID: 27844061 PMCID: PMC5103163 DOI: 10.1523/eneuro.0221-16.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 10/06/2016] [Indexed: 01/01/2023] Open
Abstract
Shudderer (Shu) is an X-linked dominant mutation in Drosophila melanogaster identified more than 40 years ago. A previous study showed that Shu caused spontaneous tremors and defects in reactive climbing behavior, and that these phenotypes were significantly suppressed when mutants were fed food containing lithium, a mood stabilizer used in the treatment of bipolar disorder (Williamson, 1982). This unique observation suggested that the Shu mutation affects genes involved in lithium-responsive neurobiological processes. In the present study, we identified Shu as a novel mutant allele of the voltage-gated sodium (Nav) channel gene paralytic (para). Given that hypomorphic para alleles and RNA interference-mediated para knockdown reduced the severity of Shu phenotypes, Shu was classified as a para hypermorphic allele. We also demonstrated that lithium could improve the behavioral abnormalities displayed by other Nav mutants, including a fly model of the human generalized epilepsy with febrile seizures plus. Our electrophysiological analysis of Shu showed that lithium treatment did not acutely suppress Nav channel activity, indicating that the rescue effect of lithium resulted from chronic physiological adjustments to this drug. Microarray analysis revealed that lithium significantly alters the expression of various genes in Shu, including those involved in innate immune responses, amino acid metabolism, and oxidation-reduction processes, raising the interesting possibility that lithium-induced modulation of these biological pathways may contribute to such adjustments. Overall, our findings demonstrate that Nav channel mutants in Drosophila are valuable genetic tools for elucidating the effects of lithium on the nervous system in the context of neurophysiology and behavior.
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35
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Huang H, Kornberg TB. Cells must express components of the planar cell polarity system and extracellular matrix to support cytonemes. eLife 2016; 5. [PMID: 27591355 PMCID: PMC5030081 DOI: 10.7554/elife.18979] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 08/31/2016] [Indexed: 01/10/2023] Open
Abstract
Drosophila dorsal air sac development depends on Decapentaplegic (Dpp) and Fibroblast growth factor (FGF) proteins produced by the wing imaginal disc and transported by cytonemes to the air sac primordium (ASP). Dpp and FGF signaling in the ASP was dependent on components of the planar cell polarity (PCP) system in the disc, and neither Dpp- nor FGF-receiving cytonemes extended over mutant disc cells that lacked them. ASP cytonemes normally navigate through extracellular matrix (ECM) composed of collagen, laminin, Dally and Dally-like (Dlp) proteins that are stratified in layers over the disc cells. However, ECM over PCP mutant cells had reduced levels of laminin, Dally and Dlp, and whereas Dpp-receiving ASP cytonemes navigated in the Dally layer and required Dally (but not Dlp), FGF-receiving ASP cytonemes navigated in the Dlp layer, requiring Dlp (but not Dally). These findings suggest that cytonemes interact directly and specifically with proteins in the stratified ECM.
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Affiliation(s)
- Hai Huang
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
| | - Thomas B Kornberg
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
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36
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Ehaideb SN, Wignall EA, Kasuya J, Evans WH, Iyengar A, Koerselman HL, Lilienthal AJ, Bassuk AG, Kitamoto T, Manak JR. Mutation of orthologous prickle genes causes a similar epilepsy syndrome in flies and humans. Ann Clin Transl Neurol 2016; 3:695-707. [PMID: 27648459 PMCID: PMC5018582 DOI: 10.1002/acn3.334] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 11/09/2022] Open
Abstract
OBJECTIVE Genetically tractable fruit flies have been used for decades to study seizure disorders. However, there is a paucity of data specifically correlating fly and human seizure phenotypes. We have previously shown that mutation of orthologous PRICKLE genes from flies to humans produce seizures. This study aimed to determine whether the prickle-mediated seizure phenotypes in flies closely parallel the epilepsy syndrome found in PRICKLE patients. METHODS Virtually all fly seizure studies have relied upon characterizing seizures that are evoked. We have developed two novel approaches to more precisely characterize seizure-related phenotypes in their native state in prickle mutant flies. First, we used high-resolution videography to document spontaneous, unprovoked seizure events. Second, we developed a locomotion coordination assay to assess whether the prickle mutant flies were ataxic. Third, we treated the mutant flies with levetiracetam to determine whether the behavioral phenotypes could be suppressed by a common antiepileptic drug. RESULTS We find that the prickle mutant flies exhibit myoclonic-like spontaneous seizure events and are severely ataxic. Both these phenotypes are found in human patients with PRICKLE mutations, and can be suppressed by levetiracetam, providing evidence that the phenotypes are due to neurological dysfunction. These results document for the first time spontaneous, unprovoked seizure events at high resolution in a fly human seizure disorder model, capturing seizures in their native state. INTERPRETATION Collectively, these data underscore the striking similarities between the fly and human PRICKLE-mediated epilepsy syndromes, and provide a genetically tractable model for dissecting the underlying causes of the human syndromic phenotypes.
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Affiliation(s)
- Salleh N Ehaideb
- Interdisciplinary Graduate Program in Genetics University of Iowa Iowa City Iowa; King Abdullah International Medical Research Cente rKing Abdulaziz Medical City Riyadh Saudi Arabia; Department of Biology University of Iowa Iowa City Iowa
| | | | - Junko Kasuya
- Department of Anesthesia University of Iowa Iowa City Iowa
| | | | - Atulya Iyengar
- Department of Biology University of Iowa Iowa City Iowa; Interdisciplinary Graduate Program in Neuroscience University of Iowa Iowa City Iowa
| | | | | | | | - Toshihiro Kitamoto
- Interdisciplinary Graduate Program in Genetics University of Iowa Iowa City Iowa; Department of Anesthesia University of Iowa Iowa City Iowa; Interdisciplinary Graduate Program in Neuroscience University of Iowa Iowa City Iowa
| | - J Robert Manak
- Interdisciplinary Graduate Program in Genetics University of Iowa Iowa City Iowa; Department of Biology University of Iowa Iowa City Iowa; Interdisciplinary Graduate Program in Neuroscience University of Iowa Iowa City Iowa; Department of Pediatrics University of Iowa Iowa City Iowa
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37
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Lim BC, Matsumoto S, Yamamoto H, Mizuno H, Kikuta J, Ishii M, Kikuchi A. Prickle1 promotes focal adhesion disassembly in cooperation with the CLASP-LL5β complex in migrating cells. J Cell Sci 2016; 129:3115-29. [PMID: 27378169 DOI: 10.1242/jcs.185439] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 06/22/2016] [Indexed: 12/16/2022] Open
Abstract
Prickle is known to be involved in planar cell polarity, including convergent extension and cell migration; however, the detailed mechanism by which Prickle regulates cellular functions is not well understood. Here, we show that Prickle1 regulates front-rear polarization and migration of gastric cancer MKN1 cells. Prickle1 preferentially accumulated at the cell retraction site in close proximity to paxillin at focal adhesions. Prickle1 dynamics correlated with those of paxillin during focal adhesion disassembly. Furthermore, Prickle1 was required for focal adhesion disassembly. CLASPs (of which there are two isoforms, CLASP1 and CLASP2, in mammals) and LL5β (also known as PHLDB2) have been reported to form a complex at cell edges and to control microtubule-dependent focal adhesion disassembly. Prickle1 was associated with CLASPs and LL5β, and was required for the LL5β-dependent accumulation of CLASPs at the cell edge. Knockdown of CLASPs and LL5β suppressed Prickle1-dependent cell polarization and migration. Prickle1 localized to the membrane through its farnesyl moiety, and the membrane localization was necessary for Prickle1 to regulate migration, to bind to CLASPs and LL5β, and to promote microtubule targeting of focal adhesions. Taken together, these results suggest that Prickle1 promotes focal adhesion disassembly during the retraction processes of cell polarization and migration.
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Affiliation(s)
- Boon Cheng Lim
- Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Shinji Matsumoto
- Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Hideki Yamamoto
- Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Hiroki Mizuno
- Department of Immunology and Cell Biology, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan WPI-Immunology Frontier Research Center, Osaka University, Yamadaoka 3-1, Suita, Osaka 565-0871, Japan
| | - Junichi Kikuta
- Department of Immunology and Cell Biology, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan WPI-Immunology Frontier Research Center, Osaka University, Yamadaoka 3-1, Suita, Osaka 565-0871, Japan
| | - Masaru Ishii
- Department of Immunology and Cell Biology, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan WPI-Immunology Frontier Research Center, Osaka University, Yamadaoka 3-1, Suita, Osaka 565-0871, Japan
| | - Akira Kikuchi
- Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
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38
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Microtubules in health and degenerative disease of the nervous system. Brain Res Bull 2016; 126:217-225. [PMID: 27365230 DOI: 10.1016/j.brainresbull.2016.06.016] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/22/2016] [Accepted: 06/27/2016] [Indexed: 01/04/2023]
Abstract
Microtubules are essential for the development and maintenance of axons and dendrites throughout the life of the neuron, and are vulnerable to degradation and disorganization in a variety of neurodegenerative diseases. Microtubules, polymers of tubulin heterodimers, are intrinsically polar structures with a plus end favored for assembly and disassembly and a minus end less favored for these dynamics. In the axon, microtubules are nearly uniformly oriented with plus ends out, whereas in dendrites, microtubules have mixed orientations. Microtubules in developing neurons typically have a stable domain toward the minus end and a labile domain toward the plus end. This domain structure becomes more complex during neuronal maturation when especially stable patches of polyaminated tubulin become more prominent within the microtubule. Microtubules are the substrates for molecular motor proteins that transport cargoes toward the plus or minus end of the microtubule, with motor-driven forces also responsible for organizing microtubules into their distinctive polarity patterns in axons and dendrites. A vast array of microtubule-regulatory proteins impart direct and indirect changes upon the microtubule arrays of the neuron, and these include microtubule-severing proteins as well as proteins responsible for the stability properties of the microtubules. During neurodegenerative diseases, microtubule mass is commonly diminished, and the potential exists for corruption of the microtubule polarity patterns and microtubule-mediated transport. These ill effects may be a primary causative factor in the disease or may be secondary effects, but regardless, therapeutics capable of correcting these microtubule abnormalities have great potential to improve the status of the degenerating nervous system.
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Chu CW, Ossipova O, Ioannou A, Sokol SY. Prickle3 synergizes with Wtip to regulate basal body organization and cilia growth. Sci Rep 2016; 6:24104. [PMID: 27062996 PMCID: PMC4827067 DOI: 10.1038/srep24104] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 03/21/2016] [Indexed: 12/21/2022] Open
Abstract
PCP proteins maintain planar polarity in many epithelial tissues and have been implicated in cilia development in vertebrate embryos. In this study we examine Prickle3 (Pk3), a vertebrate homologue of Drosophila Prickle, in Xenopus gastrocoel roof plate (GRP). GRP is a tissue equivalent to the mouse node, in which cilia-generated flow promotes left-right patterning. We show that Pk3 is enriched at the basal body of GRP cells but is recruited by Vangl2 to anterior cell borders. Interference with Pk3 function disrupted the anterior polarization of endogenous Vangl2 and the posterior localization of cilia in GRP cells, demonstrating its role in PCP. Strikingly, in cells with reduced Pk3 activity, cilia growth was inhibited and γ-tubulin and Nedd1 no longer associated with the basal body, suggesting that Pk3 has a novel function in basal body organization. Mechanistically, this function of Pk3 may involve Wilms tumor protein 1-interacting protein (Wtip), which physically associates with and cooperates with Pk3 to regulate ciliogenesis. We propose that, in addition to cell polarity, PCP components control basal body organization and function.
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Affiliation(s)
- Chih-Wen Chu
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Olga Ossipova
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Andriani Ioannou
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sergei Y Sokol
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
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40
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Bassuk AG, Sherr EH. A de novo mutation in PRICKLE1 in fetal agenesis of the corpus callosum and polymicrogyria. J Neurogenet 2016; 29:174-7. [PMID: 26727662 DOI: 10.3109/01677063.2015.1088847] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Homozygous recessive mutations in the PRICKLE1 gene were originally reported in three consanguineous families with myoclonic epilepsy. Subsequently, several studies have identified neurological abnormalities in animal models with both heterozygous and homozygous mutations in PRICKLE1 orthologues, including epilepsy in flies and in mice with heterozygous PRICKLE1 mutations. We describe a fetus with a novel de novo mutation in PRICKLE1 associated with agenesis of the corpus callosum.
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Affiliation(s)
- Alexander G Bassuk
- a Department of Pediatrics, Division of Pediatric Neurology , The University of Iowa , Iowa City , IA , USA
| | - Elliott H Sherr
- b Department of Neurology , University of California, San Francisco , San Francisco , CA , USA
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41
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Giachello CNG, Baines RA. Inappropriate Neural Activity during a Sensitive Period in Embryogenesis Results in Persistent Seizure-like Behavior. Curr Biol 2015; 25:2964-8. [PMID: 26549258 PMCID: PMC4651905 DOI: 10.1016/j.cub.2015.09.040] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 08/04/2015] [Accepted: 09/16/2015] [Indexed: 11/30/2022]
Abstract
Maturation of neural circuits requires activity-dependent processes that underpin the emergence of appropriate behavior in the adult. It has been proposed that disruption of these events, during specific critical periods when they exert maximal influence, may lead to neurodevelopmental diseases, including epilepsy [1, 2, 3]. However, complexity of neurocircuitry, coupled with the lack of information on network formation in mammals, makes it difficult to directly investigate this hypothesis. Alternative models, including the fruit fly Drosophila melanogaster, show remarkable similarities between experimental seizure-like activity and clinical phenotypes [4, 5, 6]. In particular, a group of flies, termed bang-sensitive (bs) mutants have been extensively used to investigate the pathophysiological mechanisms underlying seizure [7, 8, 9, 10, 11, 12]. Seizure phenotype can be measured in larval stages using an electroshock assay, and this behavior in bs mutants is dramatically reduced following ingestion of typical anti-epileptic drugs (AEDs; [13]). In this study we describe a critical period of embryonic development in Drosophila during which manipulation of neural activity is sufficient to significantly influence seizure behavior at postembryonic stages. We show that inhibition of elevated activity, characteristic of bs seizure models, during the critical period is sufficient to suppress seizure. By contrast, increasing neuronal excitation during the same period in wild-type (WT) is sufficient to permanently induce a seizure behavior. Further, we show that induction of seizure in WT correlates with functional alteration of motoneuron inputs that is a characteristic of bs mutants. Induction of seizure is rescued by prior administration of AEDs, opening a new perspective for early drug intervention in the treatment of genetic epilepsy. Activity manipulation defines a critical period for circuit functionality Abnormal activity during the critical period induces seizure Early drug intervention prevents seizure occurrence at postembryonic stages Seizure behavior correlates with aberrant synaptic excitation of motoneurons
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Affiliation(s)
| | - Richard A Baines
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK.
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42
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Ambegaonkar AA, Irvine KD. Coordination of planar cell polarity pathways through Spiny-legs. eLife 2015; 4. [PMID: 26505959 PMCID: PMC4764577 DOI: 10.7554/elife.09946] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 10/23/2015] [Indexed: 12/11/2022] Open
Abstract
Morphogenesis and physiology of tissues and organs requires planar cell polarity (PCP) systems that orient and coordinate cells and their behaviors, but the relationship between PCP systems has been controversial. We have characterized how the Frizzled and Dachsous-Fat PCP systems are connected through the Spiny-legs isoform of the Prickle-Spiny-legs locus. Two different components of the Dachsous-Fat system, Dachsous and Dachs, can each independently interact with Spiny-legs and direct its localization in vivo. Through characterization of the contributions of Prickle, Spiny-legs, Dachsous, Fat, and Dachs to PCP in the Drosophila wing, eye, and abdomen, we define where Dachs-Spiny-legs and Dachsous-Spiny-legs interactions contribute to PCP, and provide a new understanding of the orientation of polarity and the basis of PCP phenotypes. Our results support the direct linkage of PCP systems through Sple in specific locales, while emphasizing that cells can be subject to and must ultimately resolve distinct, competing PCP signals. DOI:http://dx.doi.org/10.7554/eLife.09946.001 Animals have many asymmetric organs. Wings, for example, are aerodynamically shaped and have a clear front, back, top and bottom, and even additions to these organs, such as feathers on the wing, often need to be oriented in a specific manner. This kind of orientation arises when cells divide and grow asymmetrically in a flat plane. The asymmetry is established at the level of single cells when proteins are not equally spread throughout a cell, but rather asymmetrically distributed. Such cells are said to be ‘planar polarized’; and many experiments addressing this so-called planar cell polarity have been conducted in fruit flies, because they can be genetically altered easily. Previous studies have shown that two signaling pathways—called Frizzled and Dachsous-Fat—regulate how individual cells orient themselves within a flat sheet of cells that forms fruit fly’s wing. The two pathways are not independent, but it is unclear how they are linked. In particular, there has been conflicting evidence as to whether the Dachsous-Fat pathway controls the Frizzled pathway or whether the two act in parallel. Now, Ambegaonkar and Irvine have discovered new roles for a protein that is involved in both pathways, called 'Spiny-legs'. This protein was known to be important in the Frizzled pathway, but, when it was tracked with a fluorescent tag in developing wing cells it also accumulated in areas where two proteins that make up part of the Dachsous-Fat pathway were located. Biochemical experiments showed that both of these proteins (which are called Dachs or Dachsous) could physically interact with Spiny-legs. Ambegaonkar and Irvine therefore deleted the genes for Dachs or Dachsous in fruit flies and observed that Spiny-legs no longer organized itself in the proper way, implying that Dachs and Dachsous control where Spiny-legs goes within cells. When this analysis was extended to other fruit fly organs, such as the eyes, Ambegaonkar and Irvine found that Dachsous was more important than Dachs for the correct localization of Spiny-legs. Additionally, the Frizzled and Dachsous-Fat pathways seemed to compete for interactions with Spiny-legs. This connection between the two pathways helps to explain how cells behave when several different signals reach them. It also shows how different organs can reuse conserved components of the pathways to make different end products. Future studies should aim to work out the number of systems that polarize cells and how they are connected in different tissues. DOI:http://dx.doi.org/10.7554/eLife.09946.002
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Affiliation(s)
- Abhijit A Ambegaonkar
- Howard Hughes Medical Institute, Rutgers University, Piscataway, United States.,Waksman Institute of Microbiology, Rutgers University, Piscataway, United States.,Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, United States
| | - Kenneth D Irvine
- Howard Hughes Medical Institute, Rutgers University, Piscataway, United States.,Waksman Institute of Microbiology, Rutgers University, Piscataway, United States.,Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, United States
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43
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Nishikawa S, Kawamoto T. Localization of Core Planar Cell Polarity Proteins, PRICKLEs, in Ameloblasts of Rat Incisors: Possible Regulation of Enamel Rod Decussation. Acta Histochem Cytochem 2015; 48:37-45. [PMID: 26175546 PMCID: PMC4427563 DOI: 10.1267/ahc.14046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 03/06/2015] [Indexed: 01/22/2023] Open
Abstract
To confirm the possible involvement of planar cell polarity proteins in odontogenesis, one group of core proteins, PRICKLE1, PRICKLE2, PRICKLE3, and PRICKLE4, was examined in enamel epithelial cells and ameloblasts by immunofluorescence microscopy. PRICKLE1 and PRICKLE2 showed similar localization in the proliferation and secretory zones of the incisor. Immunoreactive dots and short rods in ameloblasts and stratum intermedium cells were evident in the proliferation to differentiation zone, but in the secretion zone, cytoplasmic dots decreased and the distal terminal web was positive for PRICKLE1 and PRICKLE2. PRICKLE3 and PRICKLE4 showed cytoplasmic labeling in ameloblasts and other enamel epithelial cells. Double labeling of PRICKLE2 with VANGL1, which is another planar cell polarity protein, showed partial co-localization. To examine the transport route of PRICKLE proteins, PRICKLE1 localization was examined after injection of a microtubule-disrupting reagent, colchicine, and was compared with CX43, which is a membrane protein transported as vesicles via microtubules. The results confirmed the retention of immunoreactive dots for PRICKLE1 in the cytoplasm of secretory ameloblasts of colchicine-injected animals, but fewer dots were observed in control animals. These results suggest that PRICKLE1 and PRICKLE2 are transported as vesicles to the junctional area, and are involved in pattern formation of distal junctional complexes and terminal webs of ameloblasts, further implying a role in the formed enamel rod arrangement.
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Affiliation(s)
- Sumio Nishikawa
- Department of Biology, Tsurumi University School of Dental Medicine
| | - Tadafumi Kawamoto
- Radioisotope Research Institute, Tsurumi University School of Dental Medicine
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44
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Galic M, Matis M. Polarized trafficking provides spatial cues for planar cell polarization within a tissue. Bioessays 2015; 37:678-86. [PMID: 25845311 DOI: 10.1002/bies.201400196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Planar cell polarity, the polarization of cells within the plane of the epithelium, orthogonal to the apical-basal axis, is essential for a growing list of developmental events, and - over the last 15 years - has evolved from a little-studied curiosity in Drosophila to the subject of a substantial research enterprise. In that time, it has been recognized that two molecular systems are responsible for polarization of most tissues: Both the "core" Frizzled system and the "global" Fat/Dachsous/Four-jointed system produce molecular asymmetry within cells, and contribute to morphological polarization. In this review, we discuss recent findings on the molecular mechanism that links "global" directional signals with local coordinated polarity.
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Affiliation(s)
- Milos Galic
- Cells-In-Motion Cluster of Excellence (EXC1003-CiM), University of Münster, Germany.,Institute of Medical Physics and Biophysics, University of Münster, Germany
| | - Maja Matis
- Cells-In-Motion Cluster of Excellence (EXC1003-CiM), University of Münster, Germany.,Institute of Cell Biology, ZMBE, University of Münster, Germany
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45
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Seizures are regulated by ubiquitin-specific peptidase 9 X-linked (USP9X), a de-ubiquitinase. PLoS Genet 2015; 11:e1005022. [PMID: 25763846 PMCID: PMC4357451 DOI: 10.1371/journal.pgen.1005022] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 01/22/2015] [Indexed: 01/10/2023] Open
Abstract
Epilepsy is a common disabling disease with complex, multifactorial genetic and environmental etiology. The small fraction of epilepsies subject to Mendelian inheritance offers key insight into epilepsy disease mechanisms; and pathologies brought on by mutations in a single gene can point the way to generalizable therapeutic strategies. Mutations in the PRICKLE genes can cause seizures in humans, zebrafish, mice, and flies, suggesting the seizure-suppression pathway is evolutionarily conserved. This pathway has never been targeted for novel anti-seizure treatments. Here, the mammalian PRICKLE-interactome was defined, identifying prickle-interacting proteins that localize to synapses and a novel interacting partner, USP9X, a substrate-specific de-ubiquitinase. PRICKLE and USP9X interact through their carboxy-termini; and USP9X de-ubiquitinates PRICKLE, protecting it from proteasomal degradation. In forebrain neurons of mice, USP9X deficiency reduced levels of Prickle2 protein. Genetic analysis suggests the same pathway regulates Prickle-mediated seizures. The seizure phenotype was suppressed in prickle mutant flies by the small-molecule USP9X inhibitor, Degrasyn/WP1130, or by reducing the dose of fat facets a USP9X orthologue. USP9X mutations were identified by resequencing a cohort of patients with epileptic encephalopathy, one patient harbored a de novo missense mutation and another a novel coding mutation. Both USP9X variants were outside the PRICKLE-interacting domain. These findings demonstrate that USP9X inhibition can suppress prickle-mediated seizure activity, and that USP9X variants may predispose to seizures. These studies point to a new target for anti-seizure therapy and illustrate the translational power of studying diseases in species across the evolutionary spectrum. Epilepsy is a common disabling disorder characterized by seizures with complex genetic and environmental components. The absence of a definitive pathophysiology for epilepsy stymies the development of effective treatment strategies. In a small fraction of epilepsy cases however, single gene mutations may illuminate seizure-causing mechanisms, which may open the door to the discovery of broader, more effective therapeutic strategies. We have previously shown that disruption of Prickle genes in multiple species including humans, results in a predisposition to seizures. Those findings support Prickle in a seizure-preventing role and presents a possible anti-seizure therapeutic target. We identified the deubiquitinase Usp9x (ubiquitin-specific peptidase 9 X-linked) as a new Prickle binding partner which stabilized Prickle by preventing its degradation. In mice lacking the Usp9x protein in their forebrains, Prickle2 was barely detectable. In seizure-prone prickle mutant Drosophila, reducing fat facets (Drosophila usp9x) genetically or by a small-molecule usp9x inhibitor (Degrasyn/WP1130) suppressed the seizures. We also found 2 epilepsy patients harboring mutations in USP9X. Our findings demonstrate that inhibition of Usp9x can arrest prickle-mediated seizures, and variations in USP9X may predispose to seizures. From these studies, we have elucidated a seizure-inducing mechanism, identified a potential anti-seizure target, and a potential anti-seizure drug.
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46
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Manak JR. Accumulating evidence for a genetic link between epilepsy and neurodegenerative disease. FUTURE NEUROLOGY 2015. [DOI: 10.2217/fnl.14.68] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Olofsson J, Sharp KA, Matis M, Cho B, Axelrod JD. Prickle/spiny-legs isoforms control the polarity of the apical microtubule network in planar cell polarity. Development 2014; 141:2866-74. [PMID: 25005476 PMCID: PMC4197621 DOI: 10.1242/dev.105932] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 05/19/2014] [Indexed: 01/25/2023]
Abstract
Microtubules (MTs) are substrates upon which plus- and minus-end directed motors control the directional movement of cargos that are essential for generating cell polarity. Although centrosomal MTs are organized with plus-ends away from the MT organizing center, the regulation of non-centrosomal MT polarity is poorly understood. Increasing evidence supports the model that directional information for planar polarization is derived from the alignment of a parallel apical network of MTs and the directional MT-dependent trafficking of downstream signaling components. The Fat/Dachsous/Four-jointed (Ft/Ds/Fj) signaling system contributes to orienting those MTs. In addition to previously defined functions in promoting asymmetric subcellular localization of 'core' planar cell polarity (PCP) proteins, we find that alternative Prickle (Pk-Sple) protein isoforms control the polarity of this MT network. This function allows the isoforms of Pk-Sple to differentially determine the direction in which asymmetry is established and therefore, ultimately, the direction of tissue polarity. Oppositely oriented signals that are encoded by oppositely oriented Fj and Ds gradients produce the same polarity outcome in different tissues or compartments, and the tissue-specific activity of alternative Pk-Sple protein isoforms has been observed to rectify the interpretation of opposite upstream directional signals. The control of MT polarity, and thus the directionality of apical vesicle traffic, by Pk-Sple provides a mechanism for this rectification.
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Affiliation(s)
- Jessica Olofsson
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA
| | - Katherine A Sharp
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA Department of Genetics, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA
| | - Maja Matis
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA
| | - Bomsoo Cho
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA
| | - Jeffrey D Axelrod
- Department of Pathology, Stanford University School of Medicine, 300 Pasteur Drive, L235, Stanford, CA 94305, USA
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