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Hirano M, Yoshii K, Sakai M, Hasebe R, Ichii O, Kariwa H. Tick-borne flaviviruses alter membrane structure and replicate in dendrites of primary mouse neuronal cultures. J Gen Virol 2014; 95:849-861. [PMID: 24394700 DOI: 10.1099/vir.0.061432-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Neurological diseases caused by encephalitic flaviviruses are severe and associated with high levels of mortality. However, detailed mechanisms of viral replication in the brain and features of viral pathogenesis remain poorly understood. We carried out a comparative analysis of replication of neurotropic flaviviruses: West Nile virus, Japanese encephalitis virus and tick-borne encephalitis virus (TBEV), in primary cultures of mouse brain neurons. All the flaviviruses multiplied well in primary neuronal cultures from the hippocampus, cerebral cortex and cerebellum. The distribution of viral-specific antigen in the neurons varied: TBEV infection induced accumulation of viral antigen in the neuronal dendrites to a greater extent than infection with other viruses. Viral structural proteins, non-structural proteins and dsRNA were detected in regions in which viral antigens accumulated in dendrites after TBEV replication. Replication of a TBEV replicon after infection with virus-like particles of TBEV also induced antigen accumulation, indicating that accumulated viral antigen was the result of viral RNA replication. Furthermore, electron microscopy confirmed that TBEV replication induced characteristic ultrastructural membrane alterations in the neurites: newly formed laminal membrane structures containing virion-like structures. This is the first report describing viral replication in and ultrastructural alterations of neuronal dendrites, which may cause neuronal dysfunction. These findings encourage further work aimed at understanding the molecular mechanisms of viral replication in the brain and the pathogenicity of neurotropic flaviviruses.
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Affiliation(s)
- Minato Hirano
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Kentaro Yoshii
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Mizuki Sakai
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Rie Hasebe
- Laboratory of Veterinary Hygiene, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Osamu Ichii
- Laboratory of Anatomy, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Hiroaki Kariwa
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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2
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Swanger SA, Bassell GJ. Dendritic protein synthesis in the normal and diseased brain. Neuroscience 2012; 232:106-27. [PMID: 23262237 DOI: 10.1016/j.neuroscience.2012.12.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/21/2012] [Accepted: 12/01/2012] [Indexed: 01/25/2023]
Abstract
Synaptic activity is a spatially limited process that requires a precise, yet dynamic, complement of proteins within the synaptic micro-domain. The maintenance and regulation of these synaptic proteins is regulated, in part, by local mRNA translation in dendrites. Protein synthesis within the postsynaptic compartment allows neurons tight spatial and temporal control of synaptic protein expression, which is critical for proper functioning of synapses and neural circuits. In this review, we discuss the identity of proteins synthesized within dendrites, the receptor-mediated mechanisms regulating their synthesis, and the possible roles for these locally synthesized proteins. We also explore how our current understanding of dendritic protein synthesis in the hippocampus can be applied to new brain regions and to understanding the pathological mechanisms underlying varied neurological diseases.
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Affiliation(s)
- S A Swanger
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - G J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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3
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Lacoux C, Di Marino D, Boyl PP, Zalfa F, Yan B, Ciotti MT, Falconi M, Urlaub H, Achsel T, Mougin A, Caizergues-Ferrer M, Bagni C. BC1-FMRP interaction is modulated by 2'-O-methylation: RNA-binding activity of the tudor domain and translational regulation at synapses. Nucleic Acids Res 2012; 40:4086-96. [PMID: 22238374 PMCID: PMC3351191 DOI: 10.1093/nar/gkr1254] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The brain cytoplasmic RNA, BC1, is a small non-coding RNA that is found in different RNP particles, some of which are involved in translational control. One component of BC1-containing RNP complexes is the fragile X mental retardation protein (FMRP) that is implicated in translational repression. Peptide mapping and computational simulations show that the tudor domain of FMRP makes specific contacts to BC1 RNA. Endogenous BC1 RNA is 2′-O-methylated in nucleotides that contact the FMRP interface, and methylation can affect this interaction. In the cell body BC1 2′-O-methylations are present in both the nucleus and the cytoplasm, but they are virtually absent at synapses where the FMRP–BC1–mRNA complex exerts its function. These results strongly suggest that subcellular region-specific modifications of BC1 affect the binding to FMRP and the interaction with its mRNA targets. We finally show that BC1 RNA has an important role in translation of certain mRNAs associated to FMRP. All together these findings provide further insights into the translational regulation by the FMRP–BC1 complex at synapses.
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Affiliation(s)
- Caroline Lacoux
- Department of Experimental Medicine and Biochemical Sciences, Faculty of Medicine, University of Rome Tor Vergata, Via Montpellier, 1. 00133, Rome, Italy
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4
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Biological roles of translin and translin-associated factor-X: RNA metabolism comes to the fore. Biochem J 2010; 429:225-34. [PMID: 20578993 DOI: 10.1042/bj20100273] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Translin, and its binding partner protein TRAX (translin-associated factor-X) are a paralogous pair of conserved proteins, which have been implicated in a broad spectrum of biological activities, including cell growth regulation, mRNA processing, spermatogenesis, neuronal development/function, genome stability regulation and carcinogenesis, although their precise role in some of these processes remains unclear. Furthermore, translin (with or without TRAX) has nucleic-acid-binding activity and it is apparent that controlling nucleic acid metabolism and distribution are central to the biological role(s) of this protein and its partner TRAX. More recently, translin and TRAX have together been identified as enhancer components of an RNAi (RNA interference) pathway in at least one organism and this might provide critical insight into the biological roles of this enigmatic partnership. In the present review we discuss the biological and the biochemical properties of these proteins that indicate that they play a central and important role in eukaryotic cell biology.
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5
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Williams JM, Beck TF, Pearson DM, Proud MB, Cheung SW, Scott DA. A 1q42 deletion involving DISC1, DISC2, and TSNAX in an autism spectrum disorder. Am J Med Genet A 2009; 149A:1758-62. [PMID: 19606485 DOI: 10.1002/ajmg.a.32941] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Individuals with autism spectrum disorders have impairments in social, communicative, and behavior development that are often accompanied by abnormalities in cognitive functioning, learning, attention, and sensory processing. In this report, we describe a 3-year-old male child with an autism spectrum disorder who carries a 2 Mb deletion of chromosome 1q42. Array comparative genome hybridization revealed that this deletion involves at least three genes-DISC1, DISC2, and TSNAX-which have been found to be associated with neuropsychiatric disorders and are likely to play key roles in normal CNS development. Further studies revealed that the deletion was inherited from his unaffected mother. This suggests that other genetic and/or environmental factors, some of which may be sex specific, may modify the phenotypic effects of this deletion. While this case provides evidence for the potential role of DISC1, DISC2, and TSNAX in the development of autism spectrum disorders, it is equally clear that caution must be taken when providing families with prognostic information and genetic counseling regarding such deletions.
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Affiliation(s)
- Jaime M Williams
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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6
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Li Z, Wu Y, Baraban JM. The Translin/Trax RNA binding complex: clues to function in the nervous system. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2008; 1779:479-85. [PMID: 18424275 DOI: 10.1016/j.bbagrm.2008.03.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 02/26/2008] [Accepted: 03/19/2008] [Indexed: 01/11/2023]
Abstract
Translin and Trax are components of an evolutionarily conserved RNA binding complex. Deletion of Translin in yeast, Drosophila and mouse produces a dramatic loss of Trax protein indicating that its stable expression is dependent on its association with Translin. Analysis of Translin KO mice has revealed multiple behavioral abnormalities and alterations in levels of transcripts encoding synaptic proteins. A confluence of localization, biochemical and RNA trafficking studies supports the view that this complex mediates dendritic trafficking of RNAs, a process thought to play a critical role in synaptic plasticity. However, further studies are needed to define its RNA cargoes, its precise role in this process, and how its binding activity and localization are regulated. Nevertheless, there is sufficient evidence to suggest that the Translin/Trax complex be included among the cadre of RNA binding complexes, such as Staufen and CPEB, that regulate dendritic trafficking of RNA in neurons.
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Affiliation(s)
- Zhi Li
- Solomon H Snyder Department of Neuroscience, Johns Hopkins School of Medicine, USA
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7
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Abstract
The DISC locus is located at the breakpoint of a balanced t(1;11) chromosomal translocation in a large and unique Scottish family. This translocation segregates in a highly statistically significant manner with a broad diagnosis of psychiatric illness, including schizophrenia, bipolar disorder and major depression, as well as with a narrow diagnosis of schizophrenia alone. Two novel genes were identified at this locus and due to the high prevalence of schizophrenia in this family, they were named Disrupted-in-Schizophrenia-1 (DISC1) and Disrupted-in-Schizophrenia-2 (DISC2). DISC1 encodes a novel multifunctional scaffold protein, whereas DISC2 is a putative noncoding RNA gene antisense to DISC1. A number of independent genetic linkage and association studies in diverse populations support the original linkage findings in the Scottish family and genetic evidence now implicates the DISC locus in susceptibility to schizophrenia, schizoaffective disorder, bipolar disorder and major depression as well as various cognitive traits. Despite this, with the exception of the t(1;11) translocation, robust evidence for a functional variant(s) is still lacking and genetic heterogeneity is likely. Of the two genes identified at this locus, DISC1 has been prioritized as the most probable candidate susceptibility gene for psychiatric illness, as its protein sequence is directly disrupted by the translocation. Much research has been undertaken in recent years to elucidate the biological functions of the DISC1 protein and to further our understanding of how it contributes to the pathogenesis of schizophrenia. These data are the main subject of this review; however, the potential involvement of DISC2 in the pathogenesis of psychiatric illness is also discussed. A detailed picture of DISC1 function is now emerging, which encompasses roles in neurodevelopment, cytoskeletal function and cAMP signalling, and several DISC1 interactors have also been defined as independent genetic susceptibility factors for psychiatric illness. DISC1 is a hub protein in a multidimensional risk pathway for major mental illness, and studies of this pathway are opening up opportunities for a better understanding of causality and possible mechanisms of intervention.
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Affiliation(s)
- J E Chubb
- Medical Genetics Section, The Centre for Molecular Medicine, Western General Hospital, The University of Edinburgh, Edinburgh, UK
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8
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Jaendling A, Ramayah S, Pryce DW, McFarlane RJ. Functional characterisation of the Schizosaccharomyces pombe homologue of the leukaemia-associated translocation breakpoint binding protein translin and its binding partner, TRAX. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2007; 1783:203-13. [PMID: 18062930 DOI: 10.1016/j.bbamcr.2007.10.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 09/10/2007] [Accepted: 10/25/2007] [Indexed: 11/25/2022]
Abstract
Translin is a conserved protein which associates with the breakpoint junctions of chromosomal translocations linked with the development of some human cancers. It binds to both DNA and RNA and has been implicated in mRNA metabolism and regulation of genome stability. It has a binding partner, translin-associated protein X (TRAX), levels of which are regulated by the translin protein in higher eukaryotes. In this study we find that this regulatory function is conserved in the lower eukaryotes, suggesting that translin and TRAX have important functions which provide a selective advantage to both unicellular and multi-cellular eukaryotes, indicating that this function may not be tissue-specific in nature. However, to date, the biological importance of translin and TRAX remains unclear. Here we systematically investigate proposals that suggest translin and TRAX play roles in controlling mitotic cell proliferation, DNA damage responses, genome stability, meiotic/mitotic recombination and stability of GT-rich repeat sequences. We find no evidence for translin and/or TRAX primary function in these pathways, indicating that the conserved biochemical function of translin is not implicated in primary pathways for regulating genome stability and/or segregation.
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Affiliation(s)
- Alessa Jaendling
- North West Cancer Research Fund Institute, University of Wales Bangor, Bangor, Gwynedd, LL57 2UW, United Kingdom
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9
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Centonze D, Rossi S, Napoli I, Mercaldo V, Lacoux C, Ferrari F, Ciotti MT, De Chiara V, Prosperetti C, Maccarrone M, Fezza F, Calabresi P, Bernardi G, Bagni C. The brain cytoplasmic RNA BC1 regulates dopamine D2 receptor-mediated transmission in the striatum. J Neurosci 2007; 27:8885-92. [PMID: 17699670 PMCID: PMC6672174 DOI: 10.1523/jneurosci.0548-07.2007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Revised: 06/07/2007] [Accepted: 06/22/2007] [Indexed: 11/21/2022] Open
Abstract
Dopamine D(2) receptor (D(2)DR)-mediated transmission in the striatum is remarkably flexible, and changes in its efficacy have been heavily implicated in a variety of physiological and pathological conditions. Although receptor-associated proteins are clearly involved in specific forms of synaptic plasticity, the molecular mechanisms regulating the sensitivity of D(2) receptors in this brain area are essentially obscure. We have studied the physiological responses of the D(2)DR stimulations in mice lacking the brain cytoplasmic RNA BC1, a small noncoding dendritically localized RNA that is supposed to play a role in mRNA translation. We show that the efficiency of D(2)-mediated transmission regulating striatal GABA synapses is under the control of BC1 RNA, through a negative influence on D(2) receptor protein level affecting the functional pool of receptors. Ablation of the BC1 gene did not result in widespread dysregulation of synaptic transmission, because the sensitivity of cannabinoid CB(1) receptors was intact in the striatum of BC1 knock-out (KO) mice despite D(2) and CB(1) receptors mediated similar electrophysiological actions. Interestingly, the fragile X mental retardation protein FMRP, one of the multiple BC1 partners, is not involved in the BC1 effects on the D(2)-mediated transmission. Because D(2)DR mRNA is apparently equally translated in the BC1-KO and wild-type mice, whereas the protein level is higher in BC1-KO mice, we suggest that BC1 RNA controls D(2)DR indirectly, probably regulating translation of molecules involved in D(2)DR turnover and/or stability.
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MESH Headings
- Animals
- Animals, Newborn
- Biphenyl Compounds/pharmacology
- Cells, Cultured
- Corpus Striatum/cytology
- Dopamine D2 Receptor Antagonists
- Glutamate Decarboxylase/metabolism
- Guanosine 5'-O-(3-Thiotriphosphate)/pharmacokinetics
- In Vitro Techniques
- Inhibitory Postsynaptic Potentials/drug effects
- Inhibitory Postsynaptic Potentials/physiology
- Isoenzymes/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microtubule-Associated Proteins/metabolism
- Neurons/drug effects
- Neurons/physiology
- Oligonucleotides/pharmacology
- Patch-Clamp Techniques/methods
- Piperazines/pharmacology
- RNA, Long Noncoding
- RNA, Messenger/biosynthesis
- RNA, Untranslated
- Receptors, Dopamine D2/agonists
- Receptors, Dopamine D2/chemistry
- Receptors, Dopamine D2/physiology
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Ribonucleoproteins, Small Cytoplasmic/deficiency
- Ribonucleoproteins, Small Cytoplasmic/physiology
- Synaptic Transmission/drug effects
- Synaptic Transmission/physiology
- gamma-Aminobutyric Acid/metabolism
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Affiliation(s)
- Diego Centonze
- Clinica Neurologica, Dipartimento di Neuroscienze
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Silvia Rossi
- Clinica Neurologica, Dipartimento di Neuroscienze
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Ilaria Napoli
- Dipartimento di Biologia, and
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Valentina Mercaldo
- Dipartimento di Biologia, and
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Caroline Lacoux
- Dipartimento di Biologia, and
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Francesca Ferrari
- Dipartimento di Biologia, and
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Maria Teresa Ciotti
- Dipartimento di Biologia, and
- Consiglio Nazionale delle Ricerche/CERC, 00143 Rome, Italy
| | - Valentina De Chiara
- Clinica Neurologica, Dipartimento di Neuroscienze
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Chiara Prosperetti
- Clinica Neurologica, Dipartimento di Neuroscienze
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Mauro Maccarrone
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
- Dipartimento di Scienze Biomediche Comparate, Università degli Studi di Teramo, 64100 Teramo, Italy, and
| | - Filomena Fezza
- Dipartimento di Medicina Sperimentale e Scienze Biochimiche, Università Tor Vergata, 00133 Rome, Italy
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Paolo Calabresi
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
- Clinica Neurologica, Università di Perugia, Ospedale Silvestrini, 06156 Perugia, Italy
| | - Giorgio Bernardi
- Clinica Neurologica, Dipartimento di Neuroscienze
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
| | - Claudia Bagni
- Dipartimento di Biologia, and
- Fondazione Santa Lucia/Centro Europeo per la Ricerca sul Cervello (CERC), 00143 Rome, Italy
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10
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Fredholm BB, Chern Y, Franco R, Sitkovsky M. Aspects of the general biology of adenosine A2A signaling. Prog Neurobiol 2007; 83:263-76. [PMID: 17804147 DOI: 10.1016/j.pneurobio.2007.07.005] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 04/05/2007] [Accepted: 07/19/2007] [Indexed: 01/10/2023]
Abstract
Many of our current hopes of finding better ways to treat Parkinson's disease or to stop its progression rely on studies of adenosine A2A receptors in the brain. Yet any drug targeting central receptors will also potentially affect receptors in other sites. Furthermore, several fundamental aspects of adenosine receptor biology must be taken into account. For these reasons the "Targeting adenosine A2A receptors in Parkinson's disease and other CNS disorders" meeting in Boston included selected aspects of the general biology of adenosine A2A receptor signaling. Some of the presentations from this part of the meeting are summarized in this first chapter. As will be apparent to the reader, these different parts do not form an integrated whole, but they do indicate areas the organizers felt might illuminate remaining questions regarding the roles of adenosine A2A receptors. The contributors to this part of the meeting have summarized some of the key questions below.
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MESH Headings
- Adenosine/metabolism
- Animals
- Dimerization
- Encephalitis/genetics
- Encephalitis/immunology
- Encephalitis/metabolism
- Humans
- Hypoxia, Brain/genetics
- Hypoxia, Brain/immunology
- Hypoxia, Brain/metabolism
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/immunology
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Parkinson Disease/genetics
- Parkinson Disease/immunology
- Parkinson Disease/metabolism
- Receptor, Adenosine A2A/genetics
- Receptor, Adenosine A2A/metabolism
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction/genetics
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Affiliation(s)
- Bertil B Fredholm
- Department of Physiology and Pharmacology, Karolinska Institutet, S-171 77 Stockholm, Sweden.
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11
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Abstract
The vertebrate RNA and ssDNA-binding protein Translin has been suggested to function in a variety of cellular processes, including DNA damage response, RNA transport, and translational control. The Translin-associated factor X (Trax) interacts with Translin, and Trax protein stability depends on the presence of Translin. To determine the function of the Drosophila Translin and Trax, we generated a translin null mutant and isolated a trax nonsense mutation. translin and trax single and double mutants are viable, fertile, and phenotypically normal. Meiotic recombination rates and chromosome segregation are also not affected in translin and trax mutants. In addition, we found no evidence for an increased sensitivity for DNA double-strand damage in embryos and developing larvae. Together with the lack of evidence for their involvement in DNA double-strand break checkpoints, this argues against a critical role for Translin and Trax in sensing or repairing such DNA damage. However, Drosophila translin is essential for stabilizing the Translin interaction partner Trax, a function that is surprisingly conserved throughout evolution. Conversely, trax is not essential for Translin stability as trax mutants exhibit normal levels of Translin protein.
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Affiliation(s)
- Maike Claussen
- Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland
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12
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Sun CN, Cheng HC, Chou JL, Lee SY, Lin YW, Lai HL, Chen HM, Chern Y. Rescue of p53 Blockage by the A2AAdenosine Receptor via a Novel Interacting Protein, Translin-Associated Protein X. Mol Pharmacol 2006; 70:454-66. [PMID: 16617164 DOI: 10.1124/mol.105.021261] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Blockage of the p53 tumor suppressor has been found to impair nerve growth factor (NGF)-induced neurite outgrowth in PC-12 cells. We report herein that such impairment could be rescued by stimulation of the A(2A) adenosine receptor (A(2A)-R), a G protein-coupled receptor implicated in neuronal plasticity. The A(2A)-R-mediated rescue occurred in the presence of protein kinase C (PKC) inhibitors or protein kinase A (PKA) inhibitors and in a PKA-deficient PC-12 variant. Thus, neither PKA nor PKC was involved. In contrast, expression of a truncated A(2A)-R mutant harboring the seventh transmembrane domain and its C terminus reduced the rescue effect of A(2A)-R. Using the cytoplasmic tail of the A(2A)-R as bait, a novel-A(2A)-R-interacting protein [translin-associated protein X (TRAX)] was identified in a yeast two-hybrid screen. The authenticity of this interaction was verified by pull-down experiments, coimmunoprecipitation, and colocalization of these two molecules in the brain. It is noteworthy that reduction of TRAX using an antisense construct suppressed the rescue effect of A(2A)-R, whereas overexpression of TRAX alone caused the same rescue effect as did A(2A)-R activation. Results of [(3)H]thymidine and bromodeoxyuridine incorporation suggested that A(2A)-R stimulation inhibited cell proliferation in a TRAX-dependent manner. Because the antimitotic activity is crucial for NGF function, the A(2A)-R might exert its rescue effect through a TRAX-mediated antiproliferative signal. This antimitotic activity of the A(2A)-R also enables a mitogenic factor (epidermal growth factor) to induce neurite outgrowth. We demonstrate that the A(2A)-R modulates the differentiation ability of trophic factors through a novel interacting protein, TRAX.
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Affiliation(s)
- Chung-Nan Sun
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan
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13
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Stein JM, Bergman W, Fang Y, Davison L, Brensinger C, Robinson MB, Hecht NB, Abel T. Behavioral and neurochemical alterations in mice lacking the RNA-binding protein translin. J Neurosci 2006; 26:2184-96. [PMID: 16495445 PMCID: PMC6674824 DOI: 10.1523/jneurosci.4437-05.2006] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synapse-specific local protein synthesis is thought to be important for neurodevelopment and plasticity and involves neuronal RNA-binding proteins that regulate the transport and translation of dendritically localized transcripts. The best characterized of these RNA-binding proteins is the fragile X mental retardation protein (FMRP). Mutations affecting the expression or function of FMRP cause fragile X syndrome in humans, and targeted deletion of the gene encoding FMRP results in developmental and behavioral alterations in mice. Translin is an RNA-binding protein that regulates mRNA transport and translation in mouse male germ cells and is proposed to play a similar role in neurons. Like FMRP, translin is present in neuronal dendrites, binds dendritically localized RNA, and associates with microtubules and motor proteins. We reported previously the production of viable homozygous translin knock-out mice, which demonstrate altered expression of multiple mRNA transcripts in the brain and mild motor impairments. Here, we report that translin knock-out mice also exhibit sex-specific differences in tests of learning and memory, locomotor activity, anxiety-related behavior, and sensorimotor gating, as well as handling-induced seizures and alterations in monoamine neurotransmitter levels in several forebrain regions. Similar behavioral and neurochemical alterations have been observed in mice lacking FMRP, suggesting that both proteins may act within the same neuronal systems and signaling pathways. Our results in mice indicate that mutations in translin may contribute to fragile X-like syndromes, mental retardation, attention deficit hyperactivity disorder, epilepsy, and autism spectrum disorders in humans.
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14
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Kobayashi S, Kamo S, Agui K, Funakoshi T, Anzai K. Positive and negative regulators for neuronal BC1 RNA transcription by RNA polymerase III are possible members of the RNA polymerase II transcription system. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2003; 111:211-5. [PMID: 12654521 DOI: 10.1016/s0169-328x(02)00695-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neuronal cell-specific BC1 RNA is a unique RNA polymerase III (Pol III) transcript. The transcription is controlled by an activator E2 site and by BCRE, a repressor element, in response to neuronal activity. BC1 RNA is localized to dendritic domains as ribonucleoprotein particles, and it has been suggested to play a functional role in translational regulation of dendritic mRNAs. In the present study, using a luciferase assay in NG108-15 cells, we found that the positive and negative regulators for BC1 RNA transcription can also function in the Pol II transcription system. Our results suggest that the neuronal activity-dependent expression of BC1 RNA by Pol III and a subset of neuronal mRNAs by Pol II may be simultaneously controlled by the E2 site and BCRE, as well as their binding proteins.
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Affiliation(s)
- Shunsuke Kobayashi
- Department of Biochemistry, College of Pharmacy, Nihon University, 7-7-1, Narashinodai, Funabashi-shi, Chiba 274-8555, Japan
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15
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Ohashi S, Koike K, Omori A, Ichinose S, Ohara S, Kobayashi S, Sato TA, Anzai K. Identification of mRNA/protein (mRNP) complexes containing Puralpha, mStaufen, fragile X protein, and myosin Va and their association with rough endoplasmic reticulum equipped with a kinesin motor. J Biol Chem 2002; 277:37804-10. [PMID: 12147688 DOI: 10.1074/jbc.m203608200] [Citation(s) in RCA: 176] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Puralpha, which is involved in diverse aspects of cellular functions, is strongly expressed in neuronal cytoplasm. Previously, we have reported that this protein controls BC1 RNA expression and its subsequent distribution within dendrites and that Puralpha is associated with polyribosomes. Here, we report that, following treatment with EDTA, Puralpha was released from polyribosomes in mRNA/protein complexes (mRNPs), which also contained mStaufen, Fragile X Mental Retardation Protein (FMRP), myosin Va, and other proteins with unknown functions. As the coimmunoprecipitation of these proteins by an anti-Puralpha antibody was abolished by RNase treatment, Puralpha may assist mRNP assembly in an RNA-dependent manner and be involved in targeting mRNPs to polyribosomes in cooperation with other RNA-binding proteins. The immunoprecipitation of mStaufen- and FMRP-containing mRNPs provided additional evidence that the anti-Puralpha detected structurally or functionally related mRNA subsets, which are distributed in the somatodendritic compartment. Furthermore, mRNPs appear to reside on rough endoplasmic reticulum equipped with a kinesin motor. Based on our present findings, we propose that this rough endoplasmic reticulum structure may form the molecular machinery that mediates and regulates multistep transport of polyribosomes along microtubules and actin filaments, as well as localized translation in the somatodendritic compartment.
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Affiliation(s)
- Sachiyo Ohashi
- Division of Biochemistry, College of Pharmacy, Nihon University, Chiba 274-8555, Japan
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16
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Abstract
Translin is a nucleic acid binding protein that has been implicated in regulating the targeting and translation of dendritic RNA. In previous studies, we found that Translin and its partner protein, Trax, are components of a gel-shift complex that is highly enriched in brain extracts. In those studies, we employed a DNA oligonucleotide, GS1, as a probe to label the complex. Translin has also been identified as a component of a gel-shift complex detected using an RNA oligonucleotide probe, derived from the 3' UTR of protamine-2 mRNA. Although we had assumed that these probes labeled the same complex, recent studies indicate that association of Trax with Translin suppresses its RNA binding activity. As these findings challenge this assumption and suggest that the native RNA binding complex does not contain Trax, we have re-examined this issue. We have found that the gel-shift complexes labeled with either GS1 or protamine-2 probes are "supershifted" by addition of Trax antibodies, indicating that both are heteromeric Translin/Trax complexes. In addition, cross-competition studies provide additional evidence that these probes label the same complex. Furthermore, analysis of recombinant Translin/Trax complexes generated by co-transfection of Trax with Translin in hEK293T demonstrates that they are labeled with either probe. Although recombinant Translin forms a homomeric nucleic acid binding complex in vitro, our findings indicate that both Trax and Translin are components of the native gel-shift complex labeled with either GS1 or protamine-2 probes.
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Affiliation(s)
- Patricia M Finkenstadt
- Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA
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17
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Muddashetty R, Khanam T, Kondrashov A, Bundman M, Iacoangeli A, Kremerskothen J, Duning K, Barnekow A, Hüttenhofer A, Tiedge H, Brosius J. Poly(A)-binding protein is associated with neuronal BC1 and BC200 ribonucleoprotein particles. J Mol Biol 2002; 321:433-45. [PMID: 12162957 DOI: 10.1016/s0022-2836(02)00655-1] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BC1 RNA and BC200 RNA are two non-homologous, small non-messenger RNAs (snmRNAs) that were generated, evolutionarily, quite recently by retroposition. This process endowed the RNA polymerase III transcripts with central adenosine-rich regions. Both RNAs are expressed almost exclusively in neurons, where they are transported into dendritic processes as ribonucleoprotein particles (RNPs). Here, we demonstrate with a variety of experimental approaches that poly(A)-binding protein (PABP1), a regulator of translation initiation, binds to both RNAs in vitro and in vivo. We identified the association of PABP with BC200 RNA in a tri-hybrid screen and confirmed this binding in electrophoretic mobility-shift assays and via anti-PABP immunoprecipitation of BC1 and BC200 RNAs from crude extracts, immunodepleted extracts, partially purified RNPs and cells transfected with naked RNA. Furthermore, PABP immunoreactivity was localized to neuronal dendrites. Competition experiments using variants of BC1 and BC200 RNAs demonstrated that the central adenosine-rich region of both RNAs mediates binding to PABP. These findings lend support to the hypothesis that the BC1 and BC200 RNPs are involved in protein translation in neuronal dendrites.
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Affiliation(s)
- Ravi Muddashetty
- Institute of Experimental Pathology, ZMBE, University of Münster, Von-Esmarch-Str. 56, D-48149, Münster, Germany
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18
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Abstract
The heterogeneous, short RNAs produced from the high, copy, short mobile elements (SINEs) interact with proteins to form RNA-protein (RNP) complexes. In particular, the BC1 RNA, which is transcribed to high levels specifically in brain and testis from one locus of the ID SINE family, exists as a discrete RNP complex. We expressed a series of altered BC1, and other SINE-related RNAs, in several cell lines and tested for the mobility of the resulting RNP complexes in a native PAGE assay to determine which portions of these SINE RNAs contribute to protein binding. When different SINE RNAs were substituted for the BC1 ID sequence, the resulting RNPs exhibited the same mobility as BC1. This indicates that the protein(s) binding to the ID portion of BC1 is not sequence specific and may be more dependent upon the secondary structure of the RNA. It also suggests that all SINE RNAs may bind a similar set of cellular proteins. Deletion of the A-rich region of BC1 RNA has a marked effect on the mobility of the RNP. Rodent cell lines exhibit a slightly different mobility for this shifted complex when compared to human cell lines, reflecting evolutionary differences in one or more of the protein components. On the basis of mobility change observed in RNP complexes when the A-rich region is removed, we decided to examine poly(A) binding protein (PABP) as a candidate member of the RNP. An antibody against the C terminus of PABP is able to immunoprecipitate BC1 RNA, confirming PABP's presence in the BC1 RNP. Given the ubiquitous role of poly(A) regions in the retrotransposition process, these data suggest that PABP may contribute to the SINE retrotransposition process.
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Affiliation(s)
- Neva West
- Tulane Cancer Center, SL-66, Department of Environmental Health Sciences, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA
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19
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Ishida R, Okado H, Sato H, Shionoiri C, Aoki K, Kasai M. A role for the octameric ring protein, Translin, in mitotic cell division. FEBS Lett 2002; 525:105-10. [PMID: 12163170 DOI: 10.1016/s0014-5793(02)03095-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The octameric ring protein, Translin, demonstrates marked similarities to the family of helicase enzymes regarding its quaternary organization and dimerization of subunits. Here we show that the level of Translin closely parallels the proliferative state in various cell types. Expression is periodic during the cell cycle, with protein synthesis becoming maximal in the S and mitosis phases, consistent with a role in cell division. Moreover, induced overexpression of Translin was found to accelerate cell proliferation. Confocal microscopic analysis revealed that Translin is localized at the centrosomes at prophase and the mitotic spindle at metaphase, then translocating to the spindle midbodies during cytokinesis. This novel localization is attributable to specific interactions with microtubules of the mitotic spindles, and especially gamma-tubulin. The results suggest that Translin participates in processes ensuring the segregation of chromosomes and cytokinesis.
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Affiliation(s)
- Reiko Ishida
- Department of Immunology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, 162, Tokyo, Japan
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20
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Marchand S, Cartaud J. Targeted trafficking of neurotransmitter receptors to synaptic sites. Mol Neurobiol 2002; 26:117-35. [PMID: 12392061 DOI: 10.1385/mn:26:1:117] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Emerging data are sheding light on the critical task for synapses to locally control the production of neurotransmitter receptors ultimately leading to receptor accumulation and modulation at postsynaptic sites. By analogy with the epithelial-cell paradigm, the postsynaptic compartment may be regarded as a polarized domain favoring the selective recruitment and retention of newly delivered receptors at synaptic sites. Targeted delivery of receptors to synaptic sites is facilitated by a local organization of the exocytic pathway, likely resulting from spatial cues triggered by the nerve. This review focuses on the various mechanisms responsible for regulation of receptor assembly and trafficking. A particular emphasis is given to the role of synaptic anchoring and scaffolding proteins in the sorting and routing of their receptor companion along the exocytic pathway. Other cellular components such as lipidic microdomains, the docking and fusion machinery, and the cytoskeleton also contribute to the dynamics of receptor trafficking at the synapse.
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Affiliation(s)
- Sophie Marchand
- Biologie Cellulaire des Membranes, Institut Jacques Monod, UMR 7592, CNRS/Université Paris 6, France
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21
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Bray JD, Chennathukuzhi VM, Hecht NB. Identification and characterization of cDNAs encoding four novel proteins that interact with translin associated factor-X. Genomics 2002; 79:799-808. [PMID: 12036294 DOI: 10.1006/geno.2002.6779] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Translin-associated factor X (TRAX) is the predominantly cytoplasmic binding partner of TB-RBP/translin in mouse testis. Four mouse testis cDNAs encoding specific TRAX-interacting proteins were isolated from a yeast two-hybrid library screen. One novel cDNA designated Tsnaxip1 (TRAX-interacting protein-1) encodes 709 amino acids. We isolated a cDNA encoding the 427 carboxy-terminal amino acids of MEA-2, a Golgi-associated, maleenhanced autoantigen; a cDNA encoding 429 amino acids with 73% homology to centrosomal Akap9; and a cDNA encoding 346 amino acids with 75% homology to SUN1, a predicted human protein that contains a SUN domain (which is present in some perinuclear proteins). Interactions were verified using in vitro synthesized fusion proteins. All four genes were expressed in the testis and enriched in germ cells. Confocal microscopy studies using green fluorescent protein fusion proteins determined that these TRAX-interacting proteins colocalize with TRAX. The data suggest that TRAX may have a function associated with perinuclear organelles during spermatogenesis.
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Affiliation(s)
- Jeffrey D Bray
- Center for Research on Reproduction and Women's Health, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6142, USA
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22
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Lee SP, Fuior E, Lewis MS, Han MK. Analytical ultracentrifugation studies of translin: analysis of protein-DNA interactions using a single-stranded fluorogenic oligonucleotide. Biochemistry 2001; 40:14081-8. [PMID: 11705401 DOI: 10.1021/bi010302t] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Translin is a recently identified nucleic acid binding protein that appears to be involved in the recognition of conserved sequences found at many chromosomal breakpoints. Previous reports indicate that, based on gel filtration analysis and electron microscopy of protein-DNA complexes, translin forms an octameric structure that binds the DNA. In this study, we further examine the possibility of self-association of translin and its interactions with DNA by analytical ultracentrifugation. Sedimentation velocity analysis of translin indicates that the predominant species sediments with a sedimentation coefficient of 8.5 S and has a frictional ratio, f/f(omicron), of 1.35; these data are consistent with the presence of an octamer with an ellipsoidal configuration; a small amount of a component with significantly higher mass is also present. Equilibrium sedimentation studies of translin at three different protein concentrations also indicate that the predominant species present is an octamer with a minor fraction of aggregated species. Neither monomer nor dimer was detected. Sedimentation equilibrium studies of translin with an FITC-labeled single-stranded oligonucleotide were performed to examine the interaction. A novel analysis method has been developed to analyze protein-nucleic acid interactions based on global fitting of scans of 280 and 490 nm to appropriate mathematical models. Utilizing this method, it was determined that the DNA binding species of translin is an octamer binding a single-stranded oligonucleotide with a DeltaG degrees value of -9.49 +/- 0.12 kcal/mol, corresponding to a dissociation constant, K(d), of 84 +/- 17 nM. On the basis of this evidence and electron microscopy, it is envisioned that translin forms an annular structure of eight subunits, hydrodynamically an oblate ellipsoid, which binds DNA at chromosomal breakpoints.
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Affiliation(s)
- S P Lee
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20007, USA
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23
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VanLoock MS, Yu X, Kasai M, Egelman EH. Electron microscopic studies of the translin octameric ring. J Struct Biol 2001; 135:58-66. [PMID: 11562166 DOI: 10.1006/jsbi.2001.4383] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Translin is thought to participate in a variety of cellular activities including chromosomal translocations, translational regulation of mRNA expression, and mRNA transport. It forms an octameric ring structure capable of sequence-specific binding of both DNA and RNA substrates. We have used electron microscopy and single-particle image analysis to generate a three-dimensional reconstruction of the Translin ring. The subunits appear to have two distinct domains that assemble to form an open channel with diameter of approximately 30 A at one end and approximately 50 A at the opposite end. In the presence of either DNA or RNA containing consensus binding sequences, the largest opening into the central cavity is filled with density. Strikingly, although Translin shows significant sequence homology to only one other protein, Translin-associated factor X, the quaternary organization and the dimerization of subunits in the ring are very similar to those observed for hexameric ring helicases. This suggests that many of the structures in DNA and RNA metabolism may have similar quaternary organization.
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Affiliation(s)
- M S VanLoock
- Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences, Box 800733, Virginia, Charlottesville 22908-0733, USA
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24
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Li Y, Koike K, Ohashi S, Funakoshi T, Tadano M, Kobayashi S, Anzai K, Shibata N, Kobayashi M. Pur alpha protein implicated in dendritic RNA transport interacts with ribosomes in neuronal cytoplasm. Biol Pharm Bull 2001; 24:231-5. [PMID: 11256476 DOI: 10.1248/bpb.24.231] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously reported that pur alpha, known to be a regulator of DNA replication and transcription, links neural BC1 RNA to microtubules via dendrite-targeting RNA motifs. Here we demonstrate the subcellular localization of pur proteins within the brain. Pur proteins were detected in neurons but not in glia. Immunohistochemical staining was prominent in perikarya and proximal dendrites and also extended into primary dendritic processes, but no significant signals were detected in the distal regions of dendrite. When homogenates of mouse brain were fractionated, pur alpha was most concentrated in the microsomal pellet. Consistently, pur alpha co-fractionated with free polysomes as well as with membrane-bound polysomes and the association with polysomes was mediated by binding ribosomal subunits. Levels of ribosomes with pur alpha progressively increased during postnatal development of the brain.
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Affiliation(s)
- Y Li
- Department of Biochemistry, College of Pharmacy, Nihon University, Funabashi, Chiba, Japan
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25
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Ohashi S, Kobayashi S, Omori A, Ohara S, Omae A, Muramatsu T, Li Y, Anzai K. The single-stranded DNA- and RNA-binding proteins pur alpha and pur beta link BC1 RNA to microtubules through binding to the dendrite-targeting RNA motifs. J Neurochem 2000; 75:1781-90. [PMID: 11032866 DOI: 10.1046/j.1471-4159.2000.0751781.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neural BC1 RNA is distributed in neuronal dendrites as RNA-protein complexes (BC1 RNPs) containing Translin. In this study, we demonstrated that the single-stranded DNA- and RNA-binding protein pur alpha and its isoform, pur beta, which have been implicated in control of DNA replication and transcription, linked BC1 RNA to microtubules (MTs). The binding site was within the 5' proximal region of BC1 RNA containing putative dendrite-targeting RNA motifs rich in G and U residues, suggesting that in the cytoplasm of neurons, these nuclear factors are involved in the BC1 RNA transport along dendritic MTs. The pur proteins were not components of BC1 RNP but appeared to associate with MTs in brain cells. Therefore, it is suggested that they may transiently interact with the RNP during transport. In this respect, the interaction of pur proteins with BC1 RNA could be regulated by the Translin present within the RNP, because the binding mode of these two classes of proteins (pur proteins and Translin) to the dendrite-targeting RNA motifs was mutually exclusive. As the motifs are well conserved in microtubule-associated protein 2a/b mRNA as well, the pur proteins may also play a role(s) in the dendritic transport of a subset of mRNAs.
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Affiliation(s)
- S Ohashi
- Department of Biochemistry, College of Pharmacy, Nihon University, Chiba, Japan
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26
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Kobayashi S, Agui K, Kamo S, Li Y, Anzai K. Neural BC1 RNA associates with pur alpha, a single-stranded DNA and RNA binding protein, which is involved in the transcription of the BC1 RNA gene. Biochem Biophys Res Commun 2000; 277:341-7. [PMID: 11032728 DOI: 10.1006/bbrc.2000.3683] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BC1 RNA is preferentially expressed in neural cells by RNA polymerase III (Pol III) and forms ribonucleoprotein particles (RNP) in the somatodendritic domain of neurons. Our previous studies have suggested that, in the nucleus, BC1 RNA forms an RNP containing a nuclear protein(s) that participates in the transcription of the BC1 RNA gene. In this study, we have shown that newly synthesized BC1 RNA in purified brain nuclear extracts is immunoprecipitated by an antibody against Pur alpha. Pur alpha is a protein that binds single-stranded DNA and RNA and is known to regulate transcription of Pol II system. Although BC1 RNA is transcribed by Pol III, the BC1 RNA gene has two putative Pur alpha binding sites, which Pur alpha specifically recognizes. Point mutations within these sites reduced transcriptional activity in vitro. Furthermore, transcription was inhibited by depletion of Pur alpha from the nuclear extracts, either by the coexistence of its binding region of BC1 RNA or by the antibody that was able to precipitate the nuclear BC1 RNP. These observations suggest that BC1 RNA associates with Pur alpha which is involved in the transcription of the BC1 RNA gene.
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MESH Headings
- Animals
- Animals, Newborn
- Base Sequence
- Blotting, Northern
- Blotting, Western
- Brain/metabolism
- Cell Nucleus/metabolism
- Cyclic AMP Response Element-Binding Protein/metabolism
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation
- Models, Genetic
- Molecular Sequence Data
- Neurons/metabolism
- Plasmids/metabolism
- Precipitin Tests
- Protein Binding
- RNA/metabolism
- RNA, Long Noncoding
- RNA, Untranslated
- RNA-Binding Proteins/metabolism
- Rats
- Rats, Wistar
- Ribonucleoproteins, Small Cytoplasmic/genetics
- Ribonucleoproteins, Small Cytoplasmic/metabolism
- Time Factors
- Transcription Factors/metabolism
- Transcription, Genetic
- Transcriptional Activation
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Affiliation(s)
- S Kobayashi
- Department of Biochemistry, College of Pharmacy, Nihon University, Narashinodai, Funabashi, Chiba, 274-8555, Japan
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27
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Finkenstadt PM, Kang WS, Jeon M, Taira E, Tang W, Baraban JM. Somatodendritic localization of Translin, a component of the Translin/Trax RNA binding complex. J Neurochem 2000; 75:1754-62. [PMID: 10987859 DOI: 10.1046/j.1471-4159.2000.0751754.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent studies implicating dendritic protein synthesis in synaptic plasticity have focused attention on identifying components of the molecular machinery involved in processing dendritic RNA. Although Translin was originally identified as a protein capable of binding single-stranded DNA, subsequent studies have demonstrated that it also binds RNA in vitro. Because previous studies indicated that Translin-containing RNA/single-stranded DNA binding complexes are highly enriched in brain, we and others have proposed that it may be involved in dendritic RNA processing. To assess this possibility, we have conducted studies aimed at defining the localization of Translin and its partner protein, Trax, in brain. In situ hybridization studies demonstrated that both Translin and Trax are expressed in neurons with prominent staining apparent in cerebellar Purkinje cells and neuronal layers of the hippocampus. Subcellular fractionation studies demonstrated that both Translin and Trax are highly enriched in the cytoplasmic fraction compared with nuclear extracts. Furthermore, immunohistochemical studies with Translin antibodies revealed prominent staining in Purkinje neuron cell bodies that extends into proximal and distal dendrites. A similar pattern of somatodendritic localization was observed in hippocampal and neocortical pyramidal neurons. These findings demonstrate that Translin is expressed in neuronal dendrites and therefore support the hypothesis that the Translin/Trax complex may be involved in dendritic RNA processing.
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Affiliation(s)
- P M Finkenstadt
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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28
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Castro A, Peter M, Magnaghi-Jaulin L, Vigneron S, Loyaux D, Lorca T, Labbé JC. Part of Xenopus translin is localized in the centrosomes during mitosis. Biochem Biophys Res Commun 2000; 276:515-23. [PMID: 11027506 DOI: 10.1006/bbrc.2000.3482] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During oogenesis, maternal mRNAs are synthesised and stored in a translationally dormant form due to the presence of regulatory elements at the 3' untranslated regions (3'UTR). In Xenopus oocytes, several studies have described the presence of RNA-binding proteins capable to repress maternal-mRNA translation. The testis-brain RNA-binding protein (TB-RBP/Translin) is a single-stranded DNA- and RNA-binding protein which can bind the 3' UTR regions (Y and H elements) of stored mRNAs and can suppress in vitro translation of the mRNAs that contain these sequences. Here we report the cloning of the Xenopus homologue of the TB-RBP/Translin protein (X-translin) as well as its expression, its localisation, and its biochemical association with the protein named Translin associated factor X (Trax) in Xenopus oocytes. The fact that this protein is highly present in the cytoplasm from stage VI oocytes until 48 h embryos and that it has been described as capable to inhibit paternal mRNA translation, indicates that it could play an important role in maternal mRNA translation control during Xenopus oogenesis and embryogenesis. Moreover, we investigated X-translin localisation during cell cycle in XTC cells. In interphase, although a weak and diffuse nuclear staining was observed, X-translin was mostly present in the cytoplasm where it exhibited a prominent granular staining. Interestingly, part of X-translin underwent a remarkable redistribution throughout mitosis and associated with centrosomes, which may suggest a new unknown role for this protein in cell cycle.
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Affiliation(s)
- A Castro
- Centre de Recherches de Biochimie Macromoléculaire, CNRS UPR 1086, 1919 Route de Mende, Montpellier cedex 5, 34293, France
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29
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Roy AM, West NC, Rao A, Adhikari P, Alemán C, Barnes AP, Deininger PL. Upstream flanking sequences and transcription of SINEs. J Mol Biol 2000; 302:17-25. [PMID: 10964558 DOI: 10.1006/jmbi.2000.4027] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
SINEs, short interspersed repeated DNA elements, undergo amplification through retroposition and subsequent integration into a new location in the genome. Each new SINE insertion will be located in a new chromosomal environment, with different flanking sequences. Modulation of transcription by different flanking sequences may play an important role in determining which SINE elements are preferentially active in a genome. We evaluated the ability of upstream flanking sequences to regulate the transcription of three different SINEs (Alu, B2 and ID) by constructing chimeric constructs with known 5' flanking sequences of RNA polymerase III-transcribed genes. Upstream sequences from the 7SL RNA gene, U6 RNA gene, vault RNA gene, and BC1 gene increase transcription of Alu, B2 and BC1 in transient transfections of NIH3T3, HeLa, Neuro2a and C6 glioma cell lines. The 7SL sequence proved most efficient in increasing SINE transcription. The 7SL upstream fused to the BC1 RNA gene (an ID element) was used to create a transgenic mouse line. In contrast to the tissue-specific endogenous BC1 transcription, BC1 transgene transcripts were detected in all tissues tested. However, expression was much higher in those tissues that express the endogenous gene, demonstrating both transcriptional and post-transcriptional regulation. The BC1 RNA was detected in a similar ribonucleoprotein complex in the different tissues.
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Affiliation(s)
- A M Roy
- Department of Environmental Health Sciences, Tulane Cancer Center, SL-66 and, Tulane University Medical Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA
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30
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Kobayashi S, Kamo S, Ohmae A, Agui K, Li Y, Anzai K. Identification of a negative regulatory DNA element for neuronal BC1 RNA expression by RNA polymerase III. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:142-50. [PMID: 10978516 DOI: 10.1016/s0167-4781(00)00175-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BC1 RNA is a neuronal cell-specific RNA polymerase III (Pol III) transcript. The BC1 RNA gene has plural types of Pol III promoters, in addition to which an E-box sequence (E2 site) acts as a transcriptional activator, which is recognized by a brain-specific protein(s). Using an in vitro transcription system, we found that the upstream region of the BC1 RNA gene contained a sequence that interfered with the activity of the E-box element in a distance-independent manner. A tandem repeat within this sequence, which was weakly homologous with the neuron-restrictive silencer element (NRSE) found in the Pol II system, was recognized by a brain nuclear protein. Consistently, the transcriptional activity increased by deleting the tandem repeat sequence. We called this BC1 RNA-repressing element BCRE. The DNA-binding specificities of BCRE-binding protein differed from that of NRSE-binding protein (NRSF). A similar protein with an ability to bind to BCRE was also found in liver and kidney. Furthermore, the glutamate analog kainic acid increased the DNA-binding of both E2 site-binding protein and BCRE-binding protein, and then the levels of BC1 RNA also increased transiently. Our results suggested that both positive and negative regulatory elements contribute to neuronal BC1 RNA expression.
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Affiliation(s)
- S Kobayashi
- Department of Biochemistry, College of Pharmacy, Nihon University, Narashinodai, Funabashi, 274-8555, Chiba, Japan
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31
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Millar JK, Christie S, Semple CA, Porteous DJ. Chromosomal location and genomic structure of the human translin-associated factor X gene (TRAX; TSNAX) revealed by intergenic splicing to DISC1, a gene disrupted by a translocation segregating with schizophrenia. Genomics 2000; 67:69-77. [PMID: 10945471 DOI: 10.1006/geno.2000.6239] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two candidate genes, DISC1 and DISC2 on chromosome 1, are disrupted by a translocation that segregates with major psychiatric illness. Several DISC1 transcripts contain TRAX (HGMW-approved symbol TSNAX) sequence at the 5' end. These transcripts initiate at the 5' end of TRAX and terminate at the final exon of DISC1. Five species of transcript resulting from intergenic splicing have been identified; one encodes a novel TRAX/DISC1 fusion protein. The remaining four transcripts are bicistronic and encode a series of novel truncated isoforms of TRAX and DISC1. Demonstration that the various TRAX/DISC1 transcripts are translated awaits further experimentation. As a consequence of the observation of intergenic splicing, the human TRAX gene has been mapped at least 35 kb proximal to DISC1 and within approximately 150-250 kb of the translocation breakpoint at 1q42.1. The TRAX gene consists of six exons with a putative CpG island at the 5' end. Four major transcripts are produced from this gene, of which the smallest, at 2.7 kb, had previously been identified.
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Affiliation(s)
- J K Millar
- Department of Medical Sciences, The University of Edinburgh, Scotland, United Kingdom.
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Wu XQ, Hecht NB. Mouse testis brain ribonucleic acid-binding protein/translin colocalizes with microtubules and is immunoprecipitated with messenger ribonucleic acids encoding myelin basic protein, alpha calmodulin kinase II, and protamines 1 and 2. Biol Reprod 2000; 62:720-5. [PMID: 10684815 DOI: 10.1095/biolreprod62.3.720] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Testis brain RNA-binding protein (TB-RBP) is a sequence-dependent RNA-binding protein that binds to conserved Y and H sequence elements present in many brain and testis mRNAs. Using recombinant TB-RBP and a highly enriched tubulin fraction, we demonstrate here that recombinant TB-RBP binds to microtubules assembled in vitro. The interaction between recombinant TB-RBP and microtubules was inhibited by high salt and by the microtubule disassembling agents colcemid and calcium, but not by the microfilament-disassembling agent cytochalasin D. Confocal microscopy confirmed colocalization of TB-RBP and tubulin in the cytoplasm of male germ cells. An affinity-purified antibody prepared against recombinant TB-RBP specifically precipitated mRNAs encoding myelin basic protein and alpha calmodulin-dependent kinase II-two transported mRNAs, and protamines 1 and 2-two translationally regulated testicular mRNAs. These data indicate an intracellular association between TB-RBP and specific target mRNAs and suggest an involvement of TB-RBP in microtubule-dependent mRNA transport in the cytoplasm of cells.
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Affiliation(s)
- X Q Wu
- Center for Research on Reproduction and Women's Health and Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. HD 28832
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Kiebler MA, DesGroseillers L. Molecular insights into mRNA transport and local translation in the mammalian nervous system. Neuron 2000; 25:19-28. [PMID: 10707969 DOI: 10.1016/s0896-6273(00)80868-5] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- M A Kiebler
- Max-Planck-Institut für Entwicklungsbiologie, Tübingen, Federal Republic of Germany.
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Severt WL, Biber TU, Wu X, Hecht NB, DeLorenzo RJ, Jakoi ER. The suppression of testis-brain RNA binding protein and kinesin heavy chain disrupts mRNA sorting in dendrites. J Cell Sci 1999; 112 ( Pt 21):3691-702. [PMID: 10523505 DOI: 10.1242/jcs.112.21.3691] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ribonucleoprotein particles (RNPs) are thought to be key players in somato-dendritic sorting of mRNAs in CNS neurons and are implicated in activity-directed neuronal remodeling. Here, we use reporter constructs and gel mobility shift assays to show that the testis brain RNA-binding protein (TB-RBP) associates with mRNPs in a sequence (Y element) dependent manner. Using antisense oligonucleotides (anti-ODN), we demonstrate that blocking the TB-RBP Y element binding site disrupts and mis-localizes mRNPs containing (alpha)-calmodulin dependent kinase II (alpha)-CAMKII) and ligatin mRNAs. In addition, we show that suppression of kinesin heavy chain motor protein alters only the localization of (alpha)-CAMKII mRNA. Thus, differential sorting of mRNAs involves multiple mRNPs and selective motor proteins permitting localized mRNAs to utilize common mechanisms for shared steps.
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Affiliation(s)
- W L Severt
- Department of Physiology, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA 23298, USA
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Wu XQ, Lefrancois S, Morales CR, Hecht NB. Protein-protein interactions between the testis brain RNA-binding protein and the transitional endoplasmic reticulum ATPase, a cytoskeletal gamma actin and Trax in male germ cells and the brain. Biochemistry 1999; 38:11261-70. [PMID: 10471275 DOI: 10.1021/bi990573s] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Numerous functions have been proposed for the testis brain RNA-binding protein (TB-RBP) and its human homologue, Translin, ranging from mRNA transport and translational regulation to DNA rearrangement and repair. To gain insight into the likely functions of this 26 kDa protein, immunoprecipitation was used to identify proteins that interact with TB-RBP in mouse cytosolic extracts. Three proteins, the transitional endoplasmic reticulum ATPase, a cytoskeletal gamma actin, and Trax, were specifically immunoprecipitated with an affinity-purified antibody to recombinant mouse TB-RBP. In vitro binding assays with recombinant proteins and EM immunocytochemistry confirm that TB-RBP interacts with the TER ATPase in vitro and in vivo. Confocal microscopy has demonstrated that TB-RBP colocalizes with actin in the cytoplasm of male germ cells. The immunoprecipitation of Trax with TB-RBP confirms a published report demonstrating protein interactions between the two proteins in a yeast two-hybrid assay. These data support the hypothesis that TB-RBP serves as a link in attaching specific mRNAs to cytoskeletal structures and suggests an involvement for the ubiquitously expressed TER ATPase in intracellular and/or intercellular mRNA transport.
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Affiliation(s)
- X Q Wu
- Center for Research on Reproduction and Women's Health, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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Herrmann C, Golkaramnay E, Inman E, Rome L, Volknandt W. Recombinant major vault protein is targeted to neuritic tips of PC12 cells. J Biophys Biochem Cytol 1999; 144:1163-72. [PMID: 10087261 PMCID: PMC2150576 DOI: 10.1083/jcb.144.6.1163] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The major vault protein (MVP) is the predominant constituent of ubiquitous, evolutionarily conserved large cytoplasmic ribonucleoprotein particles of unknown function. Vaults are multimeric protein complexes with several copies of an untranslated RNA. Double labeling employing laser-assisted confocal microscopy and indirect immunofluorescence demonstrates partial colocalization of vaults with cytoskeletal elements in Chinese hamster ovary (CHO) and nerve growth factor (NGF)-treated neuronlike PC12 cells. Transfection of CHO and PC12 cells with a cDNA encoding the rat major vault protein containing a vesicular stomatitis virus glycoprotein epitope tag demonstrates that the recombinant protein is sorted into vault particles and targeted like endogenous MVPs. In neuritic extensions of differentiated PC12 cells, there is an almost complete overlap of the distribution of microtubules and vaults. A pronounced colocalization of vaults with filamentous actin can be seen in the tips of neurites. Moreover, in NGF-treated PC12 cells the location of vaults partially coincides with vesicular markers. Within the terminal tips of neurites vaults are located near secretory organelles. Our observations suggest that the vault particles are transported along cytoskeletal-based cellular tracks.
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Affiliation(s)
- C Herrmann
- Biozentrum der J. W. Goethe-Universität, D-60439 Frankfurt/Main, Germany
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Wu XQ, Petrusz P, Hecht NB. Testis-brain RNA-binding protein (Translin) is primarily expressed in neurons of the mouse brain. Brain Res 1999; 819:174-8. [PMID: 10082876 DOI: 10.1016/s0006-8993(98)01322-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The subcellular location(s) of the DNA- and RNA-binding protein, Testis-Brain RNA-Binding Protein (TB-RBP)/Translin in mouse brain has been determined in paraffin sections by immunocytochemistry with an affinity purified antibody to mouse recombinant TB-RBP. Nuclear staining was frequently seen in neurons throughout the brain, but no TB-RBP/Translin was detected in many of the neurons in superficial layers of the cerebral cortex and in some cells of the cerebellum. Cytoplasmic staining extending into the dendrites was seen in large neurons such as pyramidal neurons in Layer 5 of the cortex and magnocellular neurons of the hypothalamus or the brainstem raphe.
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Affiliation(s)
- X Q Wu
- Center for Research on Reproduction and Women's Health and Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, 752b Clinical Research Building, 415 Curie Boulevard, Philadelphia, PA 19104, USA
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Kobayashi S, Takashima A, Anzai K. The dendritic translocation of translin protein in the form of BC1 RNA protein particles in developing rat hippocampal neurons in primary culture. Biochem Biophys Res Commun 1998; 253:448-53. [PMID: 9878556 DOI: 10.1006/bbrc.1998.9704] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neural BC1 RNA is distributed in neuronal dendrites as ribonucleoprotein particles (RNP). Our previous studies indicated the presence of Translin in BC1 RNPs, which is a translational repressor and links a subset of mRNAs to microtubules. In this study, we confirmed that Translin associates with BC1 RNP and we used immunocytochemical methods to examine the subcellular distribution of Translin in developing hippocampal cells in primary cultures. Translin was detected in both the nuclei and cytoplasm of neurons, whereas in glial cells it was localized in the nuclei. Consistent with the reported developmental time course of BC1 RNA expression and dendritic delivery the translocation of Translin to the neuronal dendrites appeared to correlate with neuronal development and differentiation events such as the onset of synaptogenesis in culture. These observations suggest that BC1 RNP or Translin itself may be relevant to the dendritic translation of mRNAs in response to transsynaptic activity.
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Affiliation(s)
- S Kobayashi
- Division of Molecular Cell Biology, College of Pharmacy, Nihon University, Chiba, Japan
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Kremerskothen J, Nettermann M, op de Bekke A, Bachmann M, Brosius J. Identification of human autoantigen La/SS-B as BC1/BC200 RNA-binding protein. DNA Cell Biol 1998; 17:751-9. [PMID: 9778034 DOI: 10.1089/dna.1998.17.751] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Rodent BC1 RNA and primate BC200 RNA are small cytoplasmic non-messenger RNAs that are phylogenetically unrelated. Nevertheless, the two RNAs exhibit a large degree of parallelism. In addition to some sequence similarities in their 3' domains, they are prevalently expressed in a similar subset of neurons and belong to a small group of transcripts with a somatodendritic location. Both RNAs are complexed with proteins as ribonucleoprotein particles (RNPs). Their similarities may even extend to analogous functional roles, for example, in the regulation of decentralized dendritic translation. To shed further light on the physiological role(s) of the BC1/BC200 RNPs, we began to analyze protein components that specifically bind to these RNAs. Ultraviolet-crosslinking experiments and affinity purification techniques revealed that the human autoantigen La/SS-B is associated with BC1/BC200 RNA in vitro and in vivo. As with other RNA polymerase III transcripts, La protein binds with high affinity to the 3' end of BC200 RNA. Our results suggest that an additional function of La may be control of dendritic translation by providing a link between the 5' Alu domain of BC200 RNP and the ribosome via the La protein dimer. The fact that La binds both BC1 and BC200 RNAs further supports the notion that the RNAs are functional analogs despite the fact that they arose from two separate retroposition events in two different mammalian lineages.
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Affiliation(s)
- J Kremerskothen
- Institute for Experimental Pathology, Center for Molecular Biology of Inflammation, University of Münster, Germany
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