1
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Torii T, Miyamoto Y, Yamauchi J. Myelination by signaling through Arf guanine nucleotide exchange factor. J Neurochem 2024. [PMID: 38894552 DOI: 10.1111/jnc.16141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/19/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024]
Abstract
During myelination, large quantities of proteins are synthesized and transported from the endoplasmic reticulum (ER)-trans-Golgi network (TGN) to their appropriate locations within the intracellular region and/or plasma membrane. It is widely believed that oligodendrocytes uptake neuronal signals from neurons to regulate the endocytosis- and exocytosis-mediated intracellular trafficking of major myelin proteins such as myelin-associated glycoprotein (MAG) and proteolipid protein 1 (PLP1). The small GTPases of the adenosine diphosphate (ADP) ribosylation factor (Arf) family constitute a large group of signal transduction molecules that act as regulators for intracellular signaling, vesicle sorting, or membrane trafficking in cells. Studies on mice deficient in Schwann cell-specific Arfs-related genes have revealed abnormal myelination formation in peripheral nerves, indicating that Arfs-mediated signaling transduction is required for myelination in Schwann cells. However, the complex roles in these events remain poorly understood. This review aims to provide an update on signal transduction, focusing on Arf and its activator ArfGEF (guanine nucleotide exchange factor for Arf) in oligodendrocytes and Schwann cells. Future studies are expected to provide important information regarding the cellular and physiological processes underlying the myelination of oligodendrocytes and Schwann cells and their function in modulating neural activity.
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Affiliation(s)
- Tomohiro Torii
- Department of Biochemistry, Kitasato University School of Medicine, Sagamihara-shi, Kanagawa, Japan
| | - Yuki Miyamoto
- Department of Pharmacology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
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2
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Tamalin Function Is Required for the Survival of Neurons and Oligodendrocytes in the CNS. Int J Mol Sci 2022; 23:ijms232113395. [PMID: 36362204 PMCID: PMC9654138 DOI: 10.3390/ijms232113395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/30/2022] [Accepted: 10/30/2022] [Indexed: 11/06/2022] Open
Abstract
Tamalin is a post-synaptic scaffolding protein that interacts with group 1 metabotropic glutamate receptors (mGluRs) and several other proteins involved in protein trafficking and cytoskeletal events, including neuronal growth and actin reorganization. It plays an important role in synaptic plasticity in vitro by controlling the ligand-dependent trafficking of group 1 mGluRs. Abnormal regulation of mGluRs in the central nervous system (CNS) is associated with glutamate-mediated neurodegenerative disorders. However, the pathological consequences of tamalin deficiency in the CNS are unclear. In this study, tamalin knockout (KO) zebrafish and mice exhibited neurodegeneration along with oligodendrocyte degeneration in the post-embryonic CNS to adulthood without any developmental defects, thus suggesting the function of tamalin is more important in the postnatal stage to adulthood than that in CNS development. Interestingly, hypomyelination was independent of axonal defects in the CNS of tamalin knockout zebrafish and mice. In addition, the loss of Arf6, a downstream signal of tamalin scaffolding protein, synergistically induced neurodegeneration in tamalin KO zebrafish even in the developing CNS. Furthermore, tamalin KO zebrafish displayed increased mGluR5 expression. Taken together, tamalin played an important role in neuronal and oligodendrocyte survival and myelination through the regulation of mGluR5 in the CNS.
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3
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Blocking the cytohesin-2/ARF1 axis by SecinH3 ameliorates osteoclast-induced bone loss via attenuating JNK-mediated IRE1 endoribonuclease activity. Pharmacol Res 2022; 185:106513. [DOI: 10.1016/j.phrs.2022.106513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/12/2022] [Accepted: 10/12/2022] [Indexed: 11/19/2022]
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4
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Miyamoto Y, Torii T, Homma K, Oizumi H, Ohbuchi K, Mizoguchi K, Takashima S, Yamauchi J. The adaptor SH2B1 and the phosphatase PTP4A1 regulate the phosphorylation of cytohesin-2 in myelinating Schwann cells in mice. Sci Signal 2022; 15:eabi5276. [PMID: 35077201 DOI: 10.1126/scisignal.abi5276] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Mature myelin sheaths insulate axons to increase nerve conduction velocity and protect nerve fibers from stress and physical injury. In the peripheral nervous system, the myelin sheath is produced by Schwann cells. The guanine-nucleotide exchange factor cytohesin-2 activates the protein Arf6 to promote Schwann cell myelination. Here, we investigated the regulation of cytohesin-2 and found that the phosphorylation status of Tyr381 in cytohesin-2 is central to Schwann cell myelination. Knockin mice with a nonphosphorylatable Y381F mutation in cytohesin-2 exhibited reduced myelin thickness and decreased Arf6 activity in sciatic nerve tissue. In HEK293T cells, cytohesin-2 was dephosphorylated at Tyr381 by the protein tyrosine phosphatase PTP4A1, whereas phosphorylation at this site was maintained by interaction with the adaptor protein SH2B1. Schwann cell-specific knockdown of PTP4A1 in mice increased cytohesin-2 phosphorylation and myelin thickness. Conversely, Schwann cell-specific loss of SH2B1 resulted in reduced myelin thickness and decreased cytohesin-2 phosphorylation. Thus, a signaling unit centered on cytohesin-2-with SH2B1 as a positive regulator and PTP4A1 as a negative regulator-controls Schwann cell myelination in the peripheral nervous system.
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Affiliation(s)
- Yuki Miyamoto
- Laboratory of Molecular Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan.,Laboratory of Molecular Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Tomohiro Torii
- Laboratory of Ion Channel Pathophysiology, Doshisha University Graduate School of Brain Science, Kyotanabe, Kyoto 610-0394, Japan
| | - Keiichi Homma
- Department of Life Science and Informatics, Maebashi Institute of Technology, Maebashi, Gunma 371-0816, Japan
| | - Hiroaki Oizumi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki 200-1192, Japan
| | - Katsuya Ohbuchi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki 200-1192, Japan
| | - Kazushige Mizoguchi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki 200-1192, Japan
| | - Shou Takashima
- Laboratory of Glycobiology, The Noguchi Institute, Itabashi, Tokyo 173-0003, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan.,Laboratory of Molecular Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
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5
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Cytohesin-2 mediates group I metabotropic glutamate receptor-dependent mechanical allodynia through the activation of ADP ribosylation factor 6 in the spinal cord. Neurobiol Dis 2021; 159:105466. [PMID: 34390832 DOI: 10.1016/j.nbd.2021.105466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 07/20/2021] [Accepted: 08/02/2021] [Indexed: 01/15/2023] Open
Abstract
Group I metabotropic glutamate receptors (mGluRs), mGluR1 and mGluR5, in the spinal cord are implicated in nociceptive transmission and plasticity through G protein-mediated second messenger cascades leading to the activation of various protein kinases such as extracellular signal-regulated kinase (ERK). In this study, we demonstrated that cytohesin-2, a guanine nucleotide exchange factor for ADP ribosylation factors (Arfs), is abundantly expressed in subsets of excitatory interneurons and projection neurons in the superficial dorsal horn. Cytohesin-2 is enriched in the perisynapse on the postsynaptic membrane of dorsal horn neurons and forms a protein complex with mGluR5 in the spinal cord. Central nervous system-specific cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia in inflammatory and neuropathic pain models. Pharmacological blockade of cytohesin catalytic activity with SecinH3 similarly reduced mechanical allodynia and inhibited the spinal activation of Arf6, but not Arf1, in both pain models. Furthermore, cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia and ERK1/2 activation following the pharmacological activation of spinal mGluR1/5 with 3,5-dihydroxylphenylglycine (DHPG). The present study suggests that cytothesin-2 is functionally associated with mGluR5 during the development of mechanical allodynia through the activation of Arf6 in spinal dorsal horn neurons.
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Rozés-Salvador V, González-Billault C, Conde C. The Recycling Endosome in Nerve Cell Development: One Rab to Rule Them All? Front Cell Dev Biol 2020; 8:603794. [PMID: 33425908 PMCID: PMC7793921 DOI: 10.3389/fcell.2020.603794] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 11/11/2020] [Indexed: 12/13/2022] Open
Abstract
Endocytic recycling is an intracellular process that returns internalized molecules back to the plasma membrane and plays crucial roles not only in the reuse of receptor molecules but also in the remodeling of the different components of this membrane. This process is required for a diversity of cellular events, including neuronal morphology acquisition and functional regulation, among others. The recycling endosome (RE) is a key vesicular component involved in endocytic recycling. Recycling back to the cell surface may occur with the participation of several different Rab proteins, which are master regulators of membrane/protein trafficking in nerve cells. The RE consists of a network of interconnected and functionally distinct tubular subdomains that originate from sorting endosomes and transport their cargoes along microtubule tracks, by fast or slow recycling pathways. Different populations of REs, particularly those formed by Rab11, Rab35, and Arf6, are associated with a myriad of signaling proteins. In this review, we discuss the cumulative evidence suggesting the existence of heterogeneous domains of REs, controlling different aspects of neurogenesis, with a particular focus on the commonalities and singularities of these REs and their contribution to nerve development and differentiation in several animal models.
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Affiliation(s)
- Victoria Rozés-Salvador
- Instituto de Investigación Médica Mercedes y Martín Ferreyra INIMEC-CONICET-UNC, Córdoba, Argentina.,Instituto de Ciencias Básicas, Universidad Nacional de Villa María, Córdoba, Argentina
| | - Christian González-Billault
- Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile.,Department of Neurosciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Geroscience Center for Brain Health and Metabolism, Santiago, Chile.,The Buck Institute for Research on Aging, Novato, CA, United States
| | - Cecilia Conde
- Instituto de Investigación Médica Mercedes y Martín Ferreyra INIMEC-CONICET-UNC, Córdoba, Argentina
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7
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Miyamoto Y, Tanaka M, Ito H, Ooizumi H, Ohbuchi K, Mizoguchi K, Torii T, Yamauchi J. Expression of kinase-deficient MEK2 ameliorates Pelizaeus-Merzbacher disease phenotypes in mice. Biochem Biophys Res Commun 2020; 531:445-451. [PMID: 32800341 DOI: 10.1016/j.bbrc.2020.07.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 07/28/2020] [Indexed: 10/23/2022]
Abstract
Pelizaeus-Merzbacher disease (PMD) is characterized as a congenital hypomyelinating disorder in oligodendrocytes, myelin-forming glial cells in the central nervous system (CNS). The responsible gene of PMD is plp1, whose multiplication, deletion, or mutation is associated with PMD. We previously reported that primary oligodendrocytes overexpressing proteolipid protein 1 (PLP1) do not have the ability to differentiate morphologically, whereas inhibition of mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) by its cognate siRNA or chemical inhibitor reverses their undifferentiated phenotypes. Here, we show that oligodendrocyte-specific expression of kinase-deficient dominant-inhibitory mutant (MEK2K101A) of MAPK/ERK kinase 2 (MEK2), as the direct upstream molecule of MAPK/ERK in PMD model mice, promotes myelination in CNS tissues. Expression of MEK2K101A in PMD model mice also improves Rotor-rod test performance, which is often used to assess motor coordination in a rodent model with neuropathy. These results suggest that in PMD model mice, MEK2K101A can ameliorate impairments of myelination and motor function and that the signaling through MAPK/ERK may involve potential therapeutic target molecules of PMD in vivo.
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Affiliation(s)
- Yuki Miyamoto
- Laboratory of Molecular Neuroscience and Neurology, Hachioji, Tokyo, 192-0392, Japan; Laboratory of Molecular Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo, 157-8535, Japan
| | - Marina Tanaka
- Laboratory of Molecular Neuroscience and Neurology, Hachioji, Tokyo, 192-0392, Japan
| | - Hisanaka Ito
- Laboratory of Bioorganic Chemistry, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
| | - Hiroaki Ooizumi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki, 200-1192, Japan
| | - Katsuya Ohbuchi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki, 200-1192, Japan
| | - Kazushige Mizoguchi
- Tsumura Research Laboratories, Tsumura & Co., Inashiki, Ibaraki, 200-1192, Japan
| | - Tomohiro Torii
- Laboratory of Ion Channel Pathophysiology, Doshisha University, Kyotanabe, Kyoto, 610-0394, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neuroscience and Neurology, Hachioji, Tokyo, 192-0392, Japan; Laboratory of Molecular Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo, 157-8535, Japan.
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8
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Li B, Wang R, Wang Y, Stief CG, Hennenberg M. Regulation of smooth muscle contraction by monomeric non-RhoA GTPases. Br J Pharmacol 2020; 177:3865-3877. [PMID: 32579705 PMCID: PMC7429483 DOI: 10.1111/bph.15172] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/05/2020] [Accepted: 06/09/2020] [Indexed: 12/13/2022] Open
Abstract
Smooth muscle contraction in the cardiovascular system, airways, prostate and lower urinary tract is involved in the pathophysiology of many diseases, including cardiovascular and obstructive lung disease plus lower urinary tract symptoms, which are associated with high prevalence of morbidity and mortality. This prominent clinical role of smooth muscle tone has led to the molecular mechanisms involved being subjected to extensive research. In general smooth muscle contraction is promoted by three major signalling pathways, including the monomeric GTPase RhoA pathway. However, emerging evidence suggests that monomeric GTPases other than RhoA may be involved in signal transduction in smooth muscle contraction, including Rac GTPases, cell division control protein 42 homologue, adenosine ribosylation factor 6, Ras, Rap1b and Rab GTPases. Here, we review these emerging functions of non-RhoA GTPases in smooth muscle contraction, which has now become increasingly more evident and constitutes an emerging and innovative research area of high clinical relevance.
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Affiliation(s)
- Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Yiming Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
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9
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Torii T, Miyamoto Y, Yamauchi J. Cellular Signal-Regulated Schwann Cell Myelination and Remyelination. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1190:3-22. [PMID: 31760634 DOI: 10.1007/978-981-32-9636-7_1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Increasing studies have demonstrated multiple signaling molecules responsible for oligodendrocytes and Schwann cells development such as migration, differentiation, myelination, and axo-glial interaction. However, complicated roles in these events are still poorly understood. This chapter focuses on well established intracellular signaling transduction and recent topics that control myelination and are elucidated from accumulating evidences. The underlying molecular mechanisms, which involved in membrane trafficking through small GTPase Arf6 and its activator cytohesins, demonstrate the crosstalk between well established intracellular signaling transduction and a new finding signaling pathway in glial cells links to physiological phenotype and essential role in peripheral nerve system (PNS). Since Arf family proteins affect the expression levels of myelin protein zero (MPZ) and Krox20, which is a transcription factor regulatory factor in early developmental stages of Schwann cells, Arf proteins likely to be key regulator for Schwann cells development. Herein, we discuss how intracellular signaling transductions in Schwann cells associate with myelination in CNS and PNS.
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Affiliation(s)
- Tomohiro Torii
- Graduate School of Brain Science, Doshisha University, Kyotanabe-shi, Kyoto, Japan
| | - Yuki Miyamoto
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo, Japan.
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10
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Miyamoto Y, Torii T, Tago K, Tanoue A, Takashima S, Yamauchi J. BIG1/Arfgef1 and Arf1 regulate the initiation of myelination by Schwann cells in mice. SCIENCE ADVANCES 2018; 4:eaar4471. [PMID: 29740613 PMCID: PMC5938228 DOI: 10.1126/sciadv.aar4471] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 02/20/2018] [Indexed: 05/04/2023]
Abstract
During development of the peripheral nervous system in mammals, Schwann cells wrap their plasma membranes around neuronal axons, forming multiple myelin sheaths. A mature myelin sheath insulates axons and increases nerve conduction velocity while protecting nerve fibers from various stresses such as physical ones. Despite this functional importance, the molecular units that underlie dynamic morphological changes in formation of myelin sheaths are not sufficiently understood. Arf1 is a small guanosine triphosphate-binding protein that plays multiple roles in intracellular trafficking and related signaling, both of which are processes involved in cell morphogenesis. We demonstrate that the Arf1 guanine nucleotide exchange factor, brefeldin A-inhibited guanine nucleotide-exchange protein 1 (BIG1)/Arfgef1, and the effector Arf1 regulate the initiation of myelination of axons by Schwann cells. Schwann cell-specific BIG1 conditional knockout mice, which have been generated here, exhibit reduced myelin thickness and decreased localization of myelin protein zero in the myelin membrane, compared with their littermate controls. BIG1 knockout mouse nerves specifically decrease the amounts of Arf1 in the AP1 clathrin adaptor protein subunits but not the Arf1 binding to GGA1 (Golgi-localized, gamma-adaptin ear-containing, Arf-binding protein 1) transporting proteins. The amounts of Arf1 in the COPI coatomer protein subunits were comparable in the knockout mice and controls. Similar results in myelin thickness are observed in Arf1 conditional knockout mice, which have also been generated here. Thus, the BIG1 and Arf1 unit plays a key role in Schwann cell myelination, newly adding it to the list of molecular units controlling myelination.
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Grants
- Grants-in-Aid for Scientific Research from the Japanese Ministry of Education, Culture, Sports, Science, and Technology
- Branding projects for Scientific Research from the Japanese Ministry of Education, Culture, Sports, Science, and Technology
- Grants-in-Aid for Medical Scientific Research from the Japanese Ministry of Health, Labor, and Welfare
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Affiliation(s)
- Yuki Miyamoto
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Tomohiro Torii
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Kenji Tago
- Division of Structural Biochemistry, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan
| | - Akito Tanoue
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
| | - Shou Takashima
- Laboratory of Glycobiology, The Noguchi Institute, Itabashi, Tokyo 173-0003, Japan
| | - Junji Yamauchi
- Laboratory of Molecular Neuroscience and Neurology, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan
- Department of Pharmacology, National Research Institute for Child Health and Development, Setagaya, Tokyo 157-8535, Japan
- Corresponding author.
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11
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Herlemann A, Keller P, Schott M, Tamalunas A, Ciotkowska A, Rutz B, Wang Y, Yu Q, Waidelich R, Strittmatter F, Stief CG, Gratzke C, Hennenberg M. Inhibition of smooth muscle contraction and ARF6 activity by the inhibitor for cytohesin GEFs, secinH3, in the human prostate. Am J Physiol Renal Physiol 2017; 314:F47-F57. [PMID: 28855187 DOI: 10.1152/ajprenal.00125.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Prostate smooth muscle contraction is critical for etiology and treatment of male lower urinary tract symptoms (LUTS) and is promoted by small monomeric GTPases (RhoA and Rac). GTPases may be activated by guanosine nucleotide exchange factors (GEFs). GEFs of the cytohesin family may indirectly activate Rac, or ADP ribosylation factor (ARF) GTPases directly. Here we investigated the expression of cytohesin family GEFs and effects of the cytohesin inhibitor Sec7 inhibitor H3 (secinH3) on smooth muscle contraction and GTPase activities in human prostate tissues. Of all four cytohesin isoforms, cytohesin-1 and -2 showed the highest expression in real-time PCR. Western blot and fluorescence staining suggested that cytohesin-2 may be the predominant isoform in prostate smooth muscle cells. Contractions induced by norepinephrine, the α1-adrenoceptor agonist phenylephrine, the thromboxane A2 analog U-46619 , and endothelin-1 and -3, as well as neurogenic contractions induced by electric field stimulation (EFS), were reduced by secinH3 (30 µM). Inhibition of EFS-induced contractions appeared to have efficacy similar to that of inhibition by the α1-adrenoceptor antagonist tamsulosin (300 nM). Combined application of secinH3 plus tamsulosin caused larger inhibition of EFS-induced contractions than tamsulosin alone. Pull-down assays demonstrated inhibition of the small monomeric GTPase ARF6 by secinH3, but no inhibition of RhoA or Rac1. In conclusion, we suggest that a cytohesin-ARF6 pathway takes part in smooth muscle contraction. This may open attractive new possibilities in medical treatment of male LUTS.
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Affiliation(s)
- Annika Herlemann
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Patrick Keller
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Melanie Schott
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Alexander Tamalunas
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Anna Ciotkowska
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Beata Rutz
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Yiming Wang
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Qingfeng Yu
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Raphaela Waidelich
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Frank Strittmatter
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Christian G Stief
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Christian Gratzke
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
| | - Martin Hennenberg
- Department of Urology, Ludwig-Maximilians-Universität München, Munich , Germany
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12
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Data on the effect of in vivo knockdown using artificial ErbB3 miRNA on Remak bundle structure. Data Brief 2017; 12:313-319. [PMID: 28480322 PMCID: PMC5407571 DOI: 10.1016/j.dib.2017.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 03/31/2017] [Accepted: 04/11/2017] [Indexed: 11/16/2022] Open
Abstract
Mature Schwann cells, the peripheral nervous system (PNS) glial cells, have two major roles for neuronal axons (Bunge, 1993) [1]. For large diameter axons, Schwann cells form myelin sheaths with multiple layers. For small diameter axons, they form Remak bundle composed only of single layer of the Schwann cell plasma membrane. In the PNS, ErbB3 forms a dimer with ErbB2 on the Schwann cell plasma membrane. ErbB3 plays a key role in myelination by myelinating Schwann cells, that is to say, its role in myelin thickness. Herein we provide the data regarding the effect of in vivo knockdown of ErbB3 on the thickness between an axon and a neighboring axon in Remak bundle, which is formed by non-myelinating Schwann cells. Since ErbB3 knockout mice are embryonically lethal, Schwann cell lineage-specific transgenic mice transcribing ErbB3 shRNA with an artificial miRNA backbone were generated and used in these experiments (Torii et al., 2014) [2].
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Torii T, Miyamoto Y, Yamamoto M, Ohbuchi K, Tsumura H, Kawahara K, Tanoue A, Sakagami H, Yamauchi J. Arf6 mediates Schwann cell differentiation and myelination. Biochem Biophys Res Commun 2015; 465:450-7. [DOI: 10.1016/j.bbrc.2015.08.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 08/09/2015] [Indexed: 10/24/2022]
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