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Talsness DM, Owings KG, Coelho E, Mercenne G, Pleinis JM, Partha R, Hope KA, Zuberi AR, Clark NL, Lutz CM, Rodan AR, Chow CY. A Drosophila screen identifies NKCC1 as a modifier of NGLY1 deficiency. eLife 2020; 9:57831. [PMID: 33315011 PMCID: PMC7758059 DOI: 10.7554/elife.57831] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 12/12/2020] [Indexed: 12/12/2022] Open
Abstract
N-Glycanase 1 (NGLY1) is a cytoplasmic deglycosylating enzyme. Loss-of-function mutations in the NGLY1 gene cause NGLY1 deficiency, which is characterized by developmental delay, seizures, and a lack of sweat and tears. To model the phenotypic variability observed among patients, we crossed a Drosophila model of NGLY1 deficiency onto a panel of genetically diverse strains. The resulting progeny showed a phenotypic spectrum from 0 to 100% lethality. Association analysis on the lethality phenotype, as well as an evolutionary rate covariation analysis, generated lists of modifying genes, providing insight into NGLY1 function and disease. The top association hit was Ncc69 (human NKCC1/2), a conserved ion transporter. Analyses in NGLY1-/- mouse cells demonstrated that NKCC1 has an altered average molecular weight and reduced function. The misregulation of this ion transporter may explain the observed defects in secretory epithelium function in NGLY1 deficiency patients.
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Affiliation(s)
- Dana M Talsness
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
| | - Katie G Owings
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
| | - Emily Coelho
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
| | - Gaelle Mercenne
- Department of Internal Medicine, Division of Nephrology and Hypertension, and Molecular Medicine Program, University of Utah, Salt Lake City, United States
| | - John M Pleinis
- Department of Internal Medicine, Division of Nephrology and Hypertension, and Molecular Medicine Program, University of Utah, Salt Lake City, United States
| | - Raghavendran Partha
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, United States
| | - Kevin A Hope
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
| | - Aamir R Zuberi
- Genetic Resource Science, The Jackson Laboratory, Bar Harbor, United States
| | - Nathan L Clark
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
| | - Cathleen M Lutz
- Genetic Resource Science, The Jackson Laboratory, Bar Harbor, United States
| | - Aylin R Rodan
- Department of Internal Medicine, Division of Nephrology and Hypertension, and Molecular Medicine Program, University of Utah, Salt Lake City, United States.,Medical Service, Veterans Affairs Salt Lake City Health Care System, Salt Lake City, United States
| | - Clement Y Chow
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, United States
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2
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Hope KA, Flatten D, Cavitch P, May B, Sutcliffe JS, O'Donnell J, Reiter LT. The Drosophila Gene Sulfateless Modulates Autism-Like Behaviors. Front Genet 2019; 10:574. [PMID: 31316544 PMCID: PMC6611434 DOI: 10.3389/fgene.2019.00574] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/31/2019] [Indexed: 01/13/2023] Open
Abstract
Major challenges to identifying genes that contribute to autism spectrum disorder (ASD) risk include the availability of large ASD cohorts, the contribution of many genes overall, and small effect sizes attributable to common gene variants. An alternative approach is to use a model organism to detect alleles that impact ASD-relevant behaviors and ask whether homologous human genes infer ASD risk. Here we utilized the Drosophila genetic reference panel (DGRP) as a tool to probe for perturbation in naturally occurring behaviors in Drosophila melanogaster that are analogous to three behavior domains: impaired social communication, social reciprocity and repetitive behaviors or restricted interests. Using 40 of the available DGRP lines, we identified single nucleotide polymorphisms (SNPs) in or near genes controlling these behavior domains, including ASD gene orthologs (neurexin 4 and neuroligin 2), an intellectual disability (ID) gene homolog (kirre), and a gene encoding a heparan sulfate (HS) modifying enzyme called sulfateless (sfl). SNPs in sfl were associated with all three ASD-like behaviors. Using RNAi knock-down of neuronal sfl expression, we observed significant changes in expressive and receptive communication during mating, decreased grooming behavior, and increased social spacing. These results suggest a role for HS proteoglycan synthesis and/or modification in normal social communication, repetitive behavior, and social interaction in flies. Finally, using the DGRP to directly identify genetic effects relevant to a neuropsychiatric disorder further demonstrates the utility of the Drosophila system in the discovery of genes relevant to human disease.
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Affiliation(s)
- Kevin A Hope
- Integrated Program in Biological Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Daniel Flatten
- Christian Brothers University, Memphis, TN, United States
| | - Peter Cavitch
- Integrated Program in Biological Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Ben May
- Rhodes College, Memphis, TN, United States
| | - James S Sutcliffe
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States.,Department of Psychiatry, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Janis O'Donnell
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, United States
| | - Lawrence T Reiter
- Department of Neurology, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States.,Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, TN, United States
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3
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Toro C, Hori RT, Malicdan MCV, Tifft CJ, Goldstein A, Gahl WA, Adams DR, Fauni HB, Wolfe LA, Xiao J, Khan MM, Tian J, Hope KA, Reiter LT, Tremblay MG, Moss T, Franks AL, Balak C, LeDoux MS. A recurrent de novo missense mutation in UBTF causes developmental neuroregression. Hum Mol Genet 2018; 27:691-705. [PMID: 29300972 PMCID: PMC5886272 DOI: 10.1093/hmg/ddx435] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/29/2017] [Accepted: 12/19/2017] [Indexed: 12/17/2022] Open
Abstract
UBTF (upstream binding transcription factor) exists as two isoforms; UBTF1 regulates rRNA transcription by RNA polymerase 1, whereas UBTF2 regulates mRNA transcription by RNA polymerase 2. Herein, we describe 4 patients with very similar patterns of neuroregression due to recurrent de novo mutations in UBTF (GRCh37/hg19, NC_000017.10: g.42290219C > T, NM_014233.3: c.628G > A) resulting in the same amino acid change in both UBTF1 and UBTF2 (p.Glu210Lys [p.E210K]). Disease onset in our cohort was at 2.5 to 3 years and characterized by slow progression of global motor, cognitive and behavioral dysfunction. Notable early features included hypotonia with a floppy gait, high-pitched dysarthria and hyperactivity. Later features included aphasia, dystonia, and spasticity. Speech and ambulatory ability were lost by the early teens. Magnetic resonance imaging showed progressive generalized cerebral atrophy (supratentorial > infratentorial) with involvement of both gray and white matter. Patient fibroblasts showed normal levels of UBTF transcripts, increased expression of pre-rRNA and 18S rRNA, nucleolar abnormalities, markedly increased numbers of DNA breaks, defective cell-cycle progression, and apoptosis. Expression of mutant human UBTF1 in Drosophila neurons was lethal. Although no loss-of-function variants are reported in the Exome Aggregation Consortium (ExAC) database and Ubtf-/- is early embryonic lethal in mice, Ubtf+/- mice displayed only mild motor and behavioral dysfunction in adulthood. Our data underscore the importance of including UBTF E210K in the differential diagnosis of neuroregression and suggest that mainly gain-of-function mechanisms contribute to the pathogenesis of the UBTF E210K neuroregression syndrome.
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Affiliation(s)
- Camilo Toro
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Roderick T Hori
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - May Christine V Malicdan
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Cynthia J Tifft
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Amy Goldstein
- Division of Child Neurology, Department of Pediatrics, Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - William A Gahl
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - David R Adams
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Harper B Fauni
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Lynne A Wolfe
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jianfeng Xiao
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mohammad M Khan
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Jun Tian
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kevin A Hope
- Integrated Program in Biological Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Lawrence T Reiter
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Michel G Tremblay
- Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, QC, Canada
| | - Tom Moss
- Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, QC, Canada
| | - Alexis L Franks
- Division of Child Neurology, Department of Pediatrics, Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Chris Balak
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ, USA
| | - C4RCD Research Group
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ, USA
| | - Mark S LeDoux
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
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4
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Toro C, Hori RT, Malicdan MCV, Tifft CJ, Goldstein A, Gahl WA, Adams DR, Fauni HB, Wolfe LA, Xiao J, Khan MM, Tian J, Hope KA, Reiter LT, Tremblay MG, Moss T, Franks AL, Balak C, LeDoux MS. A recurrent de novo missense mutation in UBTF causes developmental neuroregression. Hum Mol Genet 2018; 27:1310. [PMID: 29447355 PMCID: PMC6093340 DOI: 10.1093/hmg/ddy049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Camilo Toro
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Roderick T Hori
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - May Christine V Malicdan
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Cynthia J Tifft
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Amy Goldstein
- Division of Child Neurology, Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - William A Gahl
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - David R Adams
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Harper B Fauni
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Lynne A Wolfe
- Undiagnosed Diseases Program and Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jianfeng Xiao
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mohammad M Khan
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Jun Tian
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kevin A Hope
- Integrated Program in Biological Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Lawrence T Reiter
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Michel G Tremblay
- Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, QC, Canada
| | - Tom Moss
- Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, QC, Canada
| | - Alexis L Franks
- Division of Child Neurology, Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Chris Balak
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ, USA
| | | | - Mark S LeDoux
- Departments of Neurology and Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
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5
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Hope KA, LeDoux MS, Reiter LT. Glial overexpression of Dube3a causes seizures and synaptic impairments in Drosophila concomitant with down regulation of the Na +/K + pump ATPα. Neurobiol Dis 2017; 108:238-248. [PMID: 28888970 PMCID: PMC5675773 DOI: 10.1016/j.nbd.2017.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/25/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022] Open
Abstract
Duplication 15q syndrome (Dup15q) is an autism-associated disorder co-incident with high rates of pediatric epilepsy. Additional copies of the E3 ubiquitin ligase UBE3A are thought to cause Dup15q phenotypes, yet models overexpressing UBE3A in neurons have not recapitulated the epilepsy phenotype. We show that Drosophila endogenously expresses Dube3a (fly UBE3A homolog) in glial cells and neurons, prompting an investigation into the consequences of glial Dube3a overexpression. Here we expand on previous work showing that the Na+/K+ pump ATPα is a direct ubiquitin ligase substrate of Dube3a. A robust seizure-like phenotype was observed in flies overexpressing Dube3a in glial cells, but not neurons. Glial-specific knockdown of ATPα also produced seizure-like behavior, and this phenotype was rescued by simultaneously overexpressing ATPα and Dube3a in glia. Our data provides the basis of a paradigm shift in Dup15q research given that clinical phenotypes have long been assumed to be due to neuronal UBE3A overexpression.
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Affiliation(s)
- Kevin A Hope
- Department of Neurology, UTHSC, Memphis, TN, United States; Integrated Biomedical Science Program, UTHSC, Memphis, TN, United States; Department of Anatomy and Neurobiology, UTHSC, Memphis, TN, United States
| | - Mark S LeDoux
- Department of Neurology, UTHSC, Memphis, TN, United States; Department of Anatomy and Neurobiology, UTHSC, Memphis, TN, United States
| | - Lawrence T Reiter
- Department of Neurology, UTHSC, Memphis, TN, United States; Department of Anatomy and Neurobiology, UTHSC, Memphis, TN, United States; Department of Pediatrics, UTHSC, Memphis, TN, United States.
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6
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Neuner SM, Wilmott LA, Hope KA, Hoffmann B, Chong JA, Abramowitz J, Birnbaumer L, O'Connell K, Tryba AK, Greene AS, Chan CS, Kaczorowski CC. Corrigendum to "TRPC3 channels critically regulate hippocampal excitability and contextual fear memory" Behav. Brain Res. 281(March) 2015, 69-77. Behav Brain Res 2017; 332:379. [PMID: 28576459 DOI: 10.1016/j.bbr.2017.05.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Sarah M Neuner
- Dept. of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Lynda A Wilmott
- Dept. of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Kevin A Hope
- Dept. of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Brian Hoffmann
- Dept. of Biotechnology and Bioengineering, Medical College of Wisconsin, Milwaukee, WI, United States
| | | | - Joel Abramowitz
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States
| | - Lutz Birnbaumer
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States
| | - Kristen O'Connell
- Dept. of Physiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Andrew K Tryba
- Dept. of Pediatrics, The University of Chicago, Chicago, IL, United States
| | - Andrew S Greene
- Dept. of Biotechnology and Bioengineering, Medical College of Wisconsin, Milwaukee, WI, United States; Dept. of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - C Savio Chan
- Dept. of Physiology, Northwestern Fienberg School of Medicine, Chicago, IL, United States
| | - Catherine C Kaczorowski
- Dept. of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States.
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7
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Abstract
In mammals, expression of UBE3A is epigenetically regulated in neurons and expression is restricted to the maternal copy of UBE3A. A recent report claimed that Drosophila melanogaster UBE3A homolog (Dube3a) is preferentially expressed from the maternal allele in fly brain, inferring an imprinting mechanism. However, complex epigenetic regulatory features of the mammalian imprinting center are not present in Drosophila, and allele specific expression of Dube3a has not been documented. We used behavioral and electrophysiological analysis of the Dube3a loss-of-function allele (Dube3a15b) to investigate Dube3a imprinting in fly neurons. We found that motor impairment (climbing ability) and a newly-characterized defect in synaptic transmission are independent of parental inheritance of the Dube3a15b allele. Furthermore, expression analysis of coding single nucleotide polymorphisms (SNPs) in Dube3a did not reveal allele specific expression differences among reciprocal crosses. These data indicate that Dube3a is neither imprinted nor preferentially expressed from the maternal allele in fly neurons.
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Affiliation(s)
- Kevin A Hope
- a Departments of Neurology , Anatomy and Neurobiology, The University of Tennessee Health Science Center , Memphis , TN , USA
| | - Mark S LeDoux
- a Departments of Neurology , Anatomy and Neurobiology, The University of Tennessee Health Science Center , Memphis , TN , USA
| | - Lawrence T Reiter
- a Departments of Neurology , Anatomy and Neurobiology, The University of Tennessee Health Science Center , Memphis , TN , USA.,b Pediatrics, The University of Tennessee Health Science Center , Memphis , TN , USA
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8
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Wilson R, Urraca N, Skobowiat C, Hope KA, Miravalle L, Chamberlin R, Donaldson M, Seagroves TN, Reiter LT. Assessment of the Tumorigenic Potential of Spontaneously Immortalized and hTERT-Immortalized Cultured Dental Pulp Stem Cells. Stem Cells Transl Med 2015; 4:905-12. [PMID: 26032749 DOI: 10.5966/sctm.2014-0196] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 04/13/2015] [Indexed: 02/07/2023] Open
Abstract
Dental pulp stem cells (DPSCs) provide an exciting new avenue to study neurogenetic disorders. DPSCs are neural crest-derived cells with the ability to differentiate into numerous tissues including neurons. The therapeutic potential of stem cell-derived lines exposed to culturing ex vivo before reintroduction into patients could be limited if the cultured cells acquired tumorigenic potential. We tested whether DPSCs that spontaneously immortalized in culture acquired features of transformed cells. We analyzed immortalized DPSCs for anchorage-independent growth, genomic instability, and ability to differentiate into neurons. Finally, we tested both spontaneously immortalized and human telomerase reverse transcriptase (hTERT)-immortalized DPSC lines for the ability to form tumors in immunocompromised animals. Although we observed increased colony-forming potential in soft agar for the spontaneously immortalized and hTERT-immortalized DPSC lines relative to low-passage DPSC, no tumors were detected from any of the DPSC lines tested. We noticed some genomic instability in hTERT-immortalized DPSCs but not in the spontaneously immortalized lines tested. We determined that immortalized DPSC lines generated in our laboratory, whether spontaneously or induced, have not acquired the potential to form tumors in mice. These data suggest cultured DPSC lines that can be differentiated into neurons may be safe for future in vivo therapy for neurobiological diseases.
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Affiliation(s)
- Ryan Wilson
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Nora Urraca
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Cezary Skobowiat
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Kevin A Hope
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Leticia Miravalle
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Reed Chamberlin
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Martin Donaldson
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Tiffany N Seagroves
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
| | - Lawrence T Reiter
- Department of Pediatric Dentistry, Department of Neurology, Center for Cancer Research, Department of Pathology, IPBS Program, and Department of Pediatrics, The University of Tennessee Health Science Center, Memphis, Tennessee, USA; Genetics Associates Inc., Nashville, Tennessee, USA
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9
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Neuner SM, Wilmott LA, Hope KA, Hoffmann B, Chong JA, Abramowitz J, Birnbaumer L, O'Connell KM, Tryba AK, Greene AS, Savio Chan C, Kaczorowski CC. TRPC3 channels critically regulate hippocampal excitability and contextual fear memory. Behav Brain Res 2014; 281:69-77. [PMID: 25513972 DOI: 10.1016/j.bbr.2014.12.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 12/08/2014] [Indexed: 01/02/2023]
Abstract
Memory formation requires de novo protein synthesis, and memory disorders may result from misregulated synthesis of critical proteins that remain largely unidentified. Plasma membrane ion channels and receptors are likely candidates given their role in regulating neuron excitability, a candidate memory mechanism. Here we conduct targeted molecular monitoring and quantitation of hippocampal plasma membrane proteins from mice with intact or impaired contextual fear memory to identify putative candidates. Here we report contextual fear memory deficits correspond to increased Trpc3 gene and protein expression, and demonstrate TRPC3 regulates hippocampal neuron excitability associated with memory function. These data provide a mechanistic explanation for enhanced contextual fear memory reported herein following knockdown of TRPC3 in hippocampus. Collectively, TRPC3 modulates memory and may be a feasible target to enhance memory and treat memory disorders.
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Affiliation(s)
- Sarah M Neuner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Lynda A Wilmott
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Kevin A Hope
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Brian Hoffmann
- Department of Biotechnology and Bioengineering, Medical College of Wisconsin, Milwaukee, WI, United States
| | | | - Joel Abramowitz
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States
| | - Lutz Birnbaumer
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States
| | - Kristen M O'Connell
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Andrew K Tryba
- Department of Pediatrics, The University of Chicago, Chicago, IL, United States
| | - Andrew S Greene
- Department of Biotechnology and Bioengineering, Medical College of Wisconsin, Milwaukee, WI, United States; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - C Savio Chan
- Department of Physiology, Northwestern Fienberg School of Medicine, Chicago, IL, United States
| | - Catherine C Kaczorowski
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN, United States.
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10
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Rose JK, Miller MK, Crane SA, Hope KA, Pittman PG. Parental and larval exposure to nicotine modulate spontaneous activity as well as cholinergic and GABA receptor expression in adult C. elegans. Neurotoxicol Teratol 2013; 39:122-7. [PMID: 23906944 DOI: 10.1016/j.ntt.2013.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Revised: 07/09/2013] [Accepted: 07/23/2013] [Indexed: 10/26/2022]
Abstract
Early nicotine exposure has been associated with many long-term consequences that include neuroanatomical alterations, as well as behavioral and cognitive deficits. To describe the effects of early nicotine exposure in Caenorhabditis elegans, the current study observed spontaneous locomotor activity (i.e., reversals) either in the presence or absence of nicotine. Expression of acr-16 (a nicotinic receptor subunit) and a β-like GABA(A) receptor subunit, gab-1, were also examined with RT-PCR. Worms were exposed to nicotine (30 μM) throughout "zygote formation" (period that includes oocyte maturation, ovulation and fertilization), from hatching to adulthood ("larval development") or across both zygote and larval development. Adult larval-exposed worms only showed an increase in spontaneous behavior when tested on nicotine (p<0.001) but levels of activity similar to controls when tested on plain plates (p>0.30). Larval-exposed worms also showed control levels of acr-16 nicotinic receptor expression (p>0.10) but increased gab-1 expression relative to controls (p<0.01). In contrast, zygote-exposed and zygote- plus larval-exposed worms showed a similar increase in spontaneous behavior on plain plates (p<0.001 and p=0.001, respectively) but control levels of responding when tested on nicotine (p>0.90 for each). However, expression of acr-16 and gab-1 was downregulated in zygote-exposed (p<0.01 and p<0.05, respectively) and significantly upregulated in the zygote- plus larval-exposed worms (p<0.000 for each); most surprising was the over five-fold increase in gab-1 expression. These results suggest that spontaneous motor behavior and receptor expression are differentially modulated by nicotine exposure during larval development and/or zygote formation. As well, these findings demonstrate that C. elegans, as a model system, is also sensitive to nicotine exposure during early development and provides the basis for future research to uncover specific mechanisms by which early nicotine exposure modifies neuronal signaling and alters behavior.
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Affiliation(s)
- Jacqueline K Rose
- Program in Behavioral Neuroscience and Department of Psychology, Western Washington University, 516 High St., Bellingham, WA, USA.
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Abstract
OBJECTIVE To discuss the effect on the international normalized ratio (INR) when patients are converted from therapy with Coumadin to generic warfarin. CASE SUMMARY Two cases at a family medicine center anticoagulation clinic in Oklahoma City, OK, in which subtherapeutic INR values occurred after a switch from Coumadin to generic warfarin, while all other variables were kept consistent demonstrate the need for close monitoring of the INR when patients are switched between brands of warfarin. DISCUSSION Warfarin is a narrow therapeutic index drug since small changes in systemic concentration can lead to significant variation in phamacodynamic response. In March 1997, the Food and Drug Administration (FDA) approved generic warfare based on the FDA and United States Pharmacopoeia (USP) standards. Due to different specifications between Dupont Pharma and the USP, content uniformity may differ between brand and generic forms of warfarin. United studies have demonstrated bioequivalence between brand and generic. The two cases presented demonstrate the potential for fluctuations in the INR when switching between generic and brand. Thus, these eases illustrate the need for close monitoring if a change is made. CONCLUSIONS While considered bioequivalent by the FDA, switching between Coumadin and generic warfarin may lead to significant changes in the INR, warranting dose alterations due to different content uniformity specifications between Dupont Pharma and the USP. Patients switching between Coumadin and generic warfarin should have their INR monitored more carefully.
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Affiliation(s)
- K A Hope
- Department of Pharmacy Practice, College of Pharmacy, University of Oklahoma, Oklahoma City 73190, USA
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