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Harada K, Sho R, Takakura H, Yokoyama E, Koyama R, Yamamoto Y, Adachi N, Tanaka S, Hide I, Sakai N. S-Palmitoylation of the serotonin transporter promotes its cell surface expression and serotonin uptake. Biochem Biophys Res Commun 2023; 662:58-65. [PMID: 37099811 DOI: 10.1016/j.bbrc.2023.04.028] [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: 03/11/2023] [Revised: 04/10/2023] [Accepted: 04/13/2023] [Indexed: 04/28/2023]
Abstract
The neurotransmitter serotonin (5-HT) is transported back into serotonergic neurons by the serotonin transporter (SERT). SERT is a main target of antidepressants, and much effort has therefore focused on finding relationships between SERT and depression. However, it is not fully understood how SERT is regulated at the cellular level. Here, we report post-translational regulation of SERT by S-palmitoylation, in which palmitate is covalently attached to cysteine residues of proteins. Using AD293 cells (a human embryonic kidney 293-derived cell line with improved cell adherence) transiently transfected with FLAG-tagged human SERT, we observed S-palmitoylation of immature SERT containing high-mannose type N-glycans or no N-glycan, which is presumed to be localized in the early secretory pathway, such as the endoplasmic reticulum. Mutational analysis by alanine substitutions shows that S-palmitoylation of immature SERT occurs at least at Cys-147 and Cys-155, juxtamembrane cysteine residues within the first intracellular loop. Furthermore, mutation of Cys-147 reduced cellular uptake of a fluorescent SERT substrate that mimics 5-HT without decreasing SERT on the cell surface. On the other hand, combined mutation of Cys-147 and Cys-155 inhibited SERT surface expression and reduced the uptake of the 5-HT mimic. Thus, S-palmitoylation of Cys-147 and Cys-155 is important for both the cell surface expression and 5-HT uptake capacity of SERT. Given the importance of S-palmitoylation in brain homeostasis, further investigation of SERT S-palmitoylation could provide new insights into the treatment of depression.
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Affiliation(s)
- Kana Harada
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
| | - Ryoma Sho
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Hiromiki Takakura
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Eri Yokoyama
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Reika Koyama
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Yuka Yamamoto
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Naoko Adachi
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501, Japan
| | - Shigeru Tanaka
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Izumi Hide
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
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2
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Nakamura M, Yoshimi A, Mouri A, Tokura T, Kimura H, Kishi S, Miyauchi T, Iwamoto K, Ito M, Sato-Boku A, Ozaki N, Nabeshima T, Noda Y. Duloxetine attenuates pain in association with downregulation of platelet serotonin transporter in patients with burning mouth syndrome and atypical odontalgia. Hum Psychopharmacol 2022; 37:e2818. [PMID: 34541697 DOI: 10.1002/hup.2818] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 08/24/2021] [Indexed: 11/10/2022]
Abstract
OBJECTIVE The aim of this study was evaluation of the association between severity of pain and expression of total or ubiquitinated serotonin transporter (SERT) protein in patients with burning mouth syndrome and atypical odontalgia (BMS/AO), who were treated by duloxetine. METHODS Patients with BMS/AO were assessed for severity of pain using the visual analog scale (VAS), and expression of total and ubiquitinated SERT protein in platelets before (baseline) and 12 weeks after duloxetine-treatment. RESULTS The expression of total and ubiquitinated SERT protein at baseline in all patients (n = 33) were higher and lower, respectively, compared to those in healthy controls. 12 weeks after duloxetine-treatment, there was no difference in the total SERT protein levels between patients (n = 21) and healthy controls. In the 16 patients who could be measured, mean VAS scores and total SERT protein levels were significantly decreased after the treatment, compared to those at baseline. There was tendency for a positive correlation between total SERT protein levels and VAS scores in these patients. CONCLUSIONS Our findings indicate that duloxetine relieves pain in association with downregulation of platelet SERT expression in patients with BMS/AO.
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Affiliation(s)
- Mariko Nakamura
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, Nagoya, Japan.,Clinical OMICs and Translation Research Center, Meijo University, Nagoya, Japan
| | - Akira Yoshimi
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, Nagoya, Japan.,Clinical OMICs and Translation Research Center, Meijo University, Nagoya, Japan.,Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akihiro Mouri
- Department of Regulatory Science for Evaluation & Development of Pharmaceuticals and Devices, Fujita Health University Graduate School of Health Science, Toyoake, Aichi, Japan
| | - Tatsuya Tokura
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroyuki Kimura
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shinichi Kishi
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tomoya Miyauchi
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Department of Psychiatry, KACHI Memorial Hospital, Toyohashi, Japan
| | - Kunihiro Iwamoto
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Mikiko Ito
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Aichi Gakuin University, Nagoya, Japan
| | - Aiji Sato-Boku
- Department of Anesthesiology, School of Dentistry, Aichi Gakuin University, Nagoya, Japan
| | - Norio Ozaki
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Toshitaka Nabeshima
- Advanced Diagnostic System Research Laboratory, Graduate School of Health Sciences, Fujita Health University, Toyoake, Aichi, Japan.,Japanese Drug Organization of Appropriate Use and Research, Nagoya, Japan
| | - Yukihiro Noda
- Division of Clinical Sciences and Neuropsychopharmacology, Graduate School of Pharmacy, Meijo University, Nagoya, Japan.,Clinical OMICs and Translation Research Center, Meijo University, Nagoya, Japan.,Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Japanese Drug Organization of Appropriate Use and Research, Nagoya, Japan
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3
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Hirakawa H, Taguchi K, Murakawa S, Asano M, Noguchi S, Kikkawa S, Harada K, Adachi N, Ueyama T, Hide I, Tanaka S, Sakai N. Effects of flurbiprofen on the functional regulation of serotonin transporter and its misfolded mutant. J Pharmacol Sci 2021; 148:187-195. [PMID: 34924125 DOI: 10.1016/j.jphs.2021.11.006] [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: 06/29/2021] [Revised: 11/05/2021] [Accepted: 11/16/2021] [Indexed: 10/19/2022] Open
Abstract
Flurbiprofen, a nonsteroidal anti-inflammatory drug, reportedly exhibits chemical chaperone activity. Herein, we investigated the role of flurbiprofen in regulating serotonin transporter (SERT) function via membrane trafficking. We used COS-7 cells transiently expressing wild-type (WT) SERT or a C-terminus-deleted mutant of SERT (SERTΔCT), a misfolded protein. Flurbiprofen treatment reduced the expression of immaturely glycosylated SERT and enhanced the expression of maturely glycosylated SERT. In addition, we observed increased serotonin uptake in SERT-expressing cells. These results suggest that flurbiprofen modulates SERT function by promoting membrane trafficking. In SERTΔCT-expressing cells, flurbiprofen reduced the protein expression and uptake activity of SERTΔCT. Furthermore, flurbiprofen inhibited the formation of SERTΔCT aggregates. Studies using flurbiprofen enantiomers suggested that these effects of flurbiprofen on SERT were not mediated via cyclooxygenase inhibition. The levels of GRP78/BiP, an endoplasmic reticulum (ER) stress marker, were assessed to elucidate whether flurbiprofen can ameliorate SERTΔCT-induced ER stress. Interestingly, flurbiprofen induced GRP78/BiP expression only under ER stress conditions and not under steady-state conditions. In HRD1 E3 ubiquitin ligase knockdown cells, flurbiprofen affected the ER-associated degradation system. Collectively, the findings suggest that flurbiprofen may function as an inducer of molecular chaperones, in addition to functioning as a chemical chaperone.
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Affiliation(s)
- Haruki Hirakawa
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kei Taguchi
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Seiya Murakawa
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masaya Asano
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Soma Noguchi
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Satoshi Kikkawa
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kana Harada
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Naoko Adachi
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Takehiko Ueyama
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Izumi Hide
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Shigeru Tanaka
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan.
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4
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Engevik M, Ruan W, Visuthranukul C, Shi Z, Engevik KA, Engevik AC, Fultz R, Schady DA, Spinler JK, Versalovic J. Limosilactobacillus reuteri ATCC 6475 metabolites upregulate the serotonin transporter in the intestinal epithelium. Benef Microbes 2021; 12:583-599. [PMID: 34550056 DOI: 10.3920/bm2020.0216] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The serotonin transporter (SERT) readily takes up serotonin (5-HT), thereby regulating the availability of 5-HT within the intestine. In the absence of SERT, 5-HT remains in the interstitial space and has the potential to aberrantly activate the many 5-HT receptors distributed on the epithelium, immune cells and enteric neurons. Perturbation of SERT is common in many gastrointestinal disorders as well as mouse models of colitis. Select commensal microbes regulate intestinal SERT levels, but the mechanism of this regulation is poorly understood. Additionally, ethanol upregulates SERT in the brain and dendritic cells, but its effects in the intestine have never been examined. We report that the intestinal commensal microbe Limosilactobacillus (previously classified as Lactobacillus) reuteri ATCC PTA 6475 secretes 83.4 mM ethanol. Consistent with the activity of L. reuteri alcohol dehydrogenases, we found that L. reuteri tolerated various levels of ethanol. Application of L. reuteri conditioned media or exogenous ethanol to human colonic T84 cells was found to upregulate SERT at the level of mRNA. A 4-(4-(dimethylamino) phenyl)-1-methylpyridinium (APP+) uptake assay confirmed the functional activity of SERT. These findings were mirrored in mouse colonic organoids, where L. reuteri metabolites and ethanol were found to upregulate SERT at the apical membrane. Finally, in a trinitrobenzene sulphonic acid model of acute colitis, we observed that mice treated with L. reuteri maintained SERT at the colon membrane compared with mice receiving phosphate buffered saline vehicle control. These data suggest that L. reuteri metabolites, including ethanol, can upregulate SERT and may be beneficial for maintaining intestinal homeostasis with respect to serotonin signalling.
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Affiliation(s)
- M Engevik
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Department of Regenerative Medicine & Cell Biology, Medical University of South Carolina, 173 Ashely Ave, BSB 626, Charleston, SC 29425, USA
| | - W Ruan
- Department of Pediatrics, Baylor College of Medicine, 6701 Fannin Street, Houston, TX 77030, USA
- Section of Gastroenterology, Hepatology, and Nutrition, Texas Children's Hospital, 6701 Fannin St, Houston, TX 77030, USA
| | - C Visuthranukul
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Pediatric Nutrition Research Unit, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Z Shi
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Department of Pathology, Texas Children's Hospital, 6621 Fannin St, Houston, TX 77030, USA
| | - K A Engevik
- Department of Molecular Virology & Microbiology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 7703, USA
| | - A C Engevik
- Departments of Surgery, Vanderbilt University Medical Center, 1211 Medical Center Dr, Nashville, TN 37232, USA
| | - R Fultz
- Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0625, USA
| | - D A Schady
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Department of Pathology, Texas Children's Hospital, 6621 Fannin St, Houston, TX 77030, USA
| | - J K Spinler
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Department of Pathology, Texas Children's Hospital, 6621 Fannin St, Houston, TX 77030, USA
| | - J Versalovic
- Department of Pathology & Immunology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA
- Department of Pathology, Texas Children's Hospital, 6621 Fannin St, Houston, TX 77030, USA
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5
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Motoike S, Taguchi K, Harada K, Asano M, Hide I, Tanaka S, Irifune M, Sakai N. Syntaxin 3 interacts with serotonin transporter and regulates its function. J Pharmacol Sci 2021; 145:297-307. [PMID: 33712280 DOI: 10.1016/j.jphs.2021.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 01/16/2021] [Accepted: 01/19/2021] [Indexed: 10/22/2022] Open
Abstract
Herein, we investigated the functional association of the serotonin transporter (SERT) with syntaxin-3 (STX3). We first overexpressed SERT and STX3 in various cells and examined their interaction, localization, and functional association. Immunoprecipitation studies revealed that STX3 interacted with SERT when expressed in COS-7 cells. Immunocytochemical studies revealed that SERT and STX3 were colocalized in the endoplasmic reticulum (ER) and Golgi apparatus. STX3 overexpression significantly reduced the uptake activity of SERT by attenuating its plasma membrane expression, suggesting that overexpressed STX3 anchors SERT in the ER and Golgi apparatus. STX3 knockdown did not affect the uptake activity of SERT but altered its glycosylation state. To elucidate the association of STX3 with SERT under physiological conditions, rather than overexpressing cells, we investigated this interaction in polarized Caco-2 cells, which endogenously express both proteins. Immunocytochemical studies revealed that SERT and STX3 were localized in microvilli-like structures at the apical plasma membrane. STX3 knockdown marginally but significantly decreased the serotonin uptake activity of Caco-2 cells, suggesting that STX3 positively regulates SERT function in Caco-2 cells, as opposed to SERT regulation by STX3 in overexpressing cells. Collectively, STX3 may colocalize with SERT during SERT membrane trafficking and regulate SERT function in an STX3-expressing lesion-dependent manner.
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Affiliation(s)
- Serika Motoike
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan; Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kei Taguchi
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kana Harada
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masaya Asano
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Izumi Hide
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Shigeru Tanaka
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masahiro Irifune
- Department of Dental Anesthesiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan.
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6
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Baudry A, Pietri M, Launay JM, Kellermann O, Schneider B. Multifaceted Regulations of the Serotonin Transporter: Impact on Antidepressant Response. Front Neurosci 2019; 13:91. [PMID: 30809118 PMCID: PMC6379337 DOI: 10.3389/fnins.2019.00091] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/25/2019] [Indexed: 12/16/2022] Open
Abstract
Serotonin transporter, SERT (SLC64A for solute carrier family 6, member A4), is a twelve transmembrane domain (TMDs) protein that assumes the uptake of serotonin (5-HT) through dissipation of the Na+ gradient established by the electrogenic pump Na/K ATPase. Abnormalities in 5-HT level and signaling have been associated with various disorders of the central nervous system (CNS) such as depression, obsessive-compulsive disorder, anxiety disorders, and autism spectrum disorder. Since the 50s, SERT has raised a lot of interest as being the target of a class of antidepressants, the Serotonin Selective Reuptake Inhibitors (SSRIs), used in clinics to combat depressive states. Because of the refractoriness of two-third of patients to SSRI treatment, a better understanding of the mechanisms regulating SERT functions is of priority. Here, we review how genetic and epigenetic regulations, post-translational modifications of SERT, and specific interactions between SERT and a set of diverse partners influence SERT expression, trafficking to and away from the plasma membrane and activity, in connection with the neuronal adaptive cell response to SSRI antidepressants.
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Affiliation(s)
- Anne Baudry
- INSERM UMR-S 1124, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1124, Paris, France
| | - Mathea Pietri
- INSERM UMR-S 1124, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1124, Paris, France
| | - Jean-Marie Launay
- Hôpital Lariboisière, AP-HP, INSERM UMR-S 942, Paris, France.,Pharma Research Department, Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Odile Kellermann
- INSERM UMR-S 1124, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1124, Paris, France
| | - Benoit Schneider
- INSERM UMR-S 1124, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1124, Paris, France
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7
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Asano M, Motoike S, Yokota C, Usuki N, Yamamoto H, Urabe T, Katarao K, Hide I, Tanaka S, Kawamoto M, Irifune M, Sakai N. SKF-10047, a prototype Sigma-1 receptor agonist, augmented the membrane trafficking and uptake activity of the serotonin transporter and its C-terminus-deleted mutant via a Sigma-1 receptor-independent mechanism. J Pharmacol Sci 2019; 139:29-36. [PMID: 30522963 DOI: 10.1016/j.jphs.2018.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 11/11/2018] [Accepted: 11/15/2018] [Indexed: 01/23/2023] Open
Abstract
The serotonin transporter (SERT) is functionally regulated via membrane trafficking. Our previous studies have demonstrated that the SERT C-terminal deletion mutant (SERTΔCT) showed a robust decrease in its membrane trafficking and was retained in the endoplasmic reticulum (ER), suggesting that SERTΔCT is an unfolded protein that may cause ER stress. The Sigma-1 receptor (SigR1) has been reported to attenuate ER stress via its chaperone activity. In this study, we investigated the effects of SKF-10047, a prototype SigR1 agonist, on the membrane trafficking and uptake activity of SERT and SERTΔCT expressed in COS-7 cells. Twenty-four hours of SKF-10047 treatment (>200 μM) accelerated SERT membrane trafficking and robustly upregulated SERTΔCT activity. Interestingly, these effects of SKF-10047 on SERT functions were also found in cells in which SigR1 expression was knocked down by shRNA, suggesting that SKF-10047 exerted these effects on SERT via a mechanism independent of SigR1. A cDNA array study identified several candidate genes involved in the mechanism of action of SKF-10047. Among them, Syntaxin3, a member of the SNARE complex, was significantly upregulated by 48 h of SKF-10047 treatment. These results suggest that SKF-10047 is a candidate for ER stress relief.
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Affiliation(s)
- Masaya Asano
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Serika Motoike
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan; Department of Dental Anesthesiology, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Chika Yokota
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Naoto Usuki
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Hikaru Yamamoto
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Tomoaki Urabe
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan; Department of Anesthesiology and Critical Care, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kazusa Katarao
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Izumi Hide
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Shigeru Tanaka
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masashi Kawamoto
- Department of Anesthesiology and Critical Care, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Masahiro Irifune
- Department of Dental Anesthesiology, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kausmi, Minami-ku, Hiroshima 734-8551, Japan.
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8
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Robichaux WG, Cheng X. Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development. Physiol Rev 2018; 98:919-1053. [PMID: 29537337 PMCID: PMC6050347 DOI: 10.1152/physrev.00025.2017] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
This review focuses on one family of the known cAMP receptors, the exchange proteins directly activated by cAMP (EPACs), also known as the cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFs). Although EPAC proteins are fairly new additions to the growing list of cAMP effectors, and relatively "young" in the cAMP discovery timeline, the significance of an EPAC presence in different cell systems is extraordinary. The study of EPACs has considerably expanded the diversity and adaptive nature of cAMP signaling associated with numerous physiological and pathophysiological responses. This review comprehensively covers EPAC protein functions at the molecular, cellular, physiological, and pathophysiological levels; and in turn, the applications of employing EPAC-based biosensors as detection tools for dissecting cAMP signaling and the implications for targeting EPAC proteins for therapeutic development are also discussed.
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Affiliation(s)
- William G Robichaux
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
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9
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Nawa Y, Kaneko H, Oda M, Tsubonoya M, Hiroi T, Gentile MT, Colucci-D'Amato L, Takahashi R, Matsui H. Functional characterization of the neuron-restrictive silencer element in the human tryptophan hydroxylase 2 gene expression. J Neurochem 2017; 142:827-840. [PMID: 28464229 DOI: 10.1111/jnc.14060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 12/24/2022]
Abstract
Tryptophan hydroxylase 2 (TPH2) is the key enzyme in the synthesis of neuronal serotonin. Although previous studies suggest that TPH2 neuron-restrictive silencer element (NRSE) functions as a negative regulator dependent on neuron-restrictive silencer factor (NRSF) activity, the underlying mechanisms are yet to be fully elucidated. Here, we show a detailed analysis of the NRSE-mediated repression of the human TPH2 (hTPH2) promoter activity in RN46A cells, a cell line derived from rat raphe neurons. Quantitative real-time RT-PCR analysis revealed the expression of serotonergic marker genes (Mash1, Nkx2.2, Gata2, Gata3, Lmx1b, Pet-1, 5-Htt, and Vmat2) and Nrsf gene in RN46A cells. Tph1 mRNA is the prevalent form expressed in RN46A cells; Tph2 mRNA is also expressed but at a lower level. Electrophoretic mobility shift assays and reporter assays showed that hTPH2 NRSE is necessary for the efficient DNA binding of NRSF and for the NRSF-dependent repression of the hTPH2 promoter activity. The hTPH2 promoter activity was increased by knockdown of NRSF, or over-expression of the engineered NRSF (a dominant-negative mutant or a DNA-binding domain and activation domain fusion protein). MS-275, a class I histone deacetylase (HDAC) inhibitor, was found to be more potent than MC-1568, a class II HDAC inhibitor, in enhancing the hTPH2 promoter activity. Furthermore, treatment with the ubiquitin-specific protease 7 deubiquitinase inhibitors, P-22077 or HBX 41108, increased the hTPH2 promoter activity. Collectively, our data demonstrate that the hTPH2 NRSE-mediated promoter repression via NRSF involves class I HDACs and is modulated by the ubiquitin-specific protease 7-mediated deubiquitination and stabilization of NRSF.
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Affiliation(s)
- Yukino Nawa
- Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
| | - Hanae Kaneko
- Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
| | - Masayuki Oda
- Department of Pharmacogenomics, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
| | - Masaaki Tsubonoya
- Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
| | - Tomoko Hiroi
- Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
| | - Maria Teresa Gentile
- Laboratory of Molecular and Cellular Pathology, Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Luca Colucci-D'Amato
- Laboratory of Molecular and Cellular Pathology, Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Ryoya Takahashi
- Department of Biochemistry, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Japan
| | - Hiroaki Matsui
- Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, Kawasaki, Japan.,Department of Molecular and Behavioral Neuroscience, St. Marianna University Graduate School of Medicine, Kawasaki, Japan
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10
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Katarao K, Murakawa S, Asano M, Usuki N, Yamamoto H, Shirafuji T, Tanaka S, Hide I, Sakai N. The Development of Screening Methods to Identify Drugs to Limit ER Stress Using Wild-type and Mutant Serotonin Transporter. Acta Histochem Cytochem 2016; 49:197-206. [PMID: 28127108 PMCID: PMC5263230 DOI: 10.1267/ahc.16029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 10/25/2016] [Indexed: 11/22/2022] Open
Abstract
The function of the serotonin transporter (SERT) is regulated by its membrane trafficking. Previously, we showed that the C-terminus-deleted mutant of SERT (SERTΔCT) exhibited an aberrant membrane trafficking and subsequent retention at the endoplasmic reticulum (ER). In addition, we found that proteasome inhibitor-induced ER stress resulted in the impairment of SERT membrane trafficking and retention of SERT at the ER, an impairment very similar to that of SERTΔCT. Based on the result that the chemical chaperone 4-phnylbutulic acid (4-PBA), which relieves ER stress, accelerated the membrane trafficking and upregulated SERT activity, we hypothesized that drugs that facilitate the membrane trafficking of SERT would have potential therapeutic effects on an ER stress-related disease. In this study, we aimed to develop simple screening methods for such drugs using SERT. We first validated the serotonin uptake assay using fluorescent substrates. This simple and reliable assay method was useful for screening for drugs that affected the wild-type SERT but not SERTΔCT. In addition, we verified an assay focusing on the formation of SERTΔCT aggregates. The drugs 4-PBA and SKF-10047 facilitated the trafficking of SERT to the membrane and reduced SERTΔCT aggregates, indicating that the drugs with such characters could be potential candidates for ER stress relief. For both assays, we clarified the usefulness of a high-content screening microscope. These results could pave the way for high-throughput screening for such drugs.
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Affiliation(s)
- Kazusa Katarao
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Seiya Murakawa
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Masaya Asano
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Naoto Usuki
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Hikaru Yamamoto
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Toshihiko Shirafuji
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Shigeru Tanaka
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Izumi Hide
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
| | - Norio Sakai
- Department of Molecular and Pharmacological Neuroscience, Institute of Biomedical & Health Sciences, Hiroshima University
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11
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Bermingham DP, Blakely RD. Kinase-dependent Regulation of Monoamine Neurotransmitter Transporters. Pharmacol Rev 2016; 68:888-953. [PMID: 27591044 PMCID: PMC5050440 DOI: 10.1124/pr.115.012260] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Modulation of neurotransmission by the monoamines dopamine (DA), norepinephrine (NE), and serotonin (5-HT) is critical for normal nervous system function. Precise temporal and spatial control of this signaling in mediated in large part by the actions of monoamine transporters (DAT, NET, and SERT, respectively). These transporters act to recapture their respective neurotransmitters after release, and disruption of clearance and reuptake has significant effects on physiology and behavior and has been linked to a number of neuropsychiatric disorders. To ensure adequate and dynamic control of these transporters, multiple modes of control have evolved to regulate their activity and trafficking. Central to many of these modes of control are the actions of protein kinases, whose actions can be direct or indirectly mediated by kinase-modulated protein interactions. Here, we summarize the current state of our understanding of how protein kinases regulate monoamine transporters through changes in activity, trafficking, phosphorylation state, and interacting partners. We highlight genetic, biochemical, and pharmacological evidence for kinase-linked control of DAT, NET, and SERT and, where applicable, provide evidence for endogenous activators of these pathways. We hope our discussion can lead to a more nuanced and integrated understanding of how neurotransmitter transporters are controlled and may contribute to disorders that feature perturbed monoamine signaling, with an ultimate goal of developing better therapeutic strategies.
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Affiliation(s)
- Daniel P Bermingham
- Department of Pharmacology (D.P.B., R.D.B.) and Psychiatry (R.D.B.), Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Biomedical Sciences, Charles E. Schmidt College of Medicine and Brain Institute, Florida Atlantic University, Jupiter, Florida (R.D.B.)
| | - Randy D Blakely
- Department of Pharmacology (D.P.B., R.D.B.) and Psychiatry (R.D.B.), Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Biomedical Sciences, Charles E. Schmidt College of Medicine and Brain Institute, Florida Atlantic University, Jupiter, Florida (R.D.B.)
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12
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Yamasaki A, Kasai A, Toi A, Kurita M, Kimoto S, Hayata-Takano A, Nakazawa T, Nagayasu K, Shintani N, Hashimoto R, Ito A, Meltzer HY, Ago Y, Waschek JA, Onaka Y, Matsuda T, Baba A, Hashimoto H. Identification of the role of bone morphogenetic protein (BMP) and transforming growth factor-β (TGF-β) signaling in the trajectory of serotonergic differentiation in a rapid assay in mouse embryonic stem cells in vitro. J Neurochem 2015; 132:418-28. [PMID: 25421849 DOI: 10.1111/jnc.12999] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 10/18/2014] [Accepted: 11/15/2014] [Indexed: 12/25/2022]
Abstract
The mechanism by which extracellular molecules control serotonergic cell fate remains elusive. Recently, we showed that noggin, which inactivates bone morphogenetic proteins (BMPs), induces serotonergic differentiation of mouse embryonic (ES) and induced pluripotent stem cells with coordinated gene expression along the serotonergic lineage. Here, we created a rapid assay for serotonergic induction by generating knock-in ES cells expressing a naturally secreted Gaussia luciferase driven by the enhancer of Pet-1/Fev, a landmark of serotonergic differentiation. Using these cells, we performed candidate-based screening and identified BMP type I receptor kinase inhibitors LDN-193189 and DMH1 as activators of luciferase. LDN-193189 induced ES cells to express the genes encoding Pet-1, tryptophan hydroxylase 2, and the serotonin transporter, and increased serotonin release without altering dopamine release. In contrast, TGF-β receptor inhibitor SB-431542 selectively inhibited serotonergic differentiation, without changing overall neuronal differentiation. LDN-193189 inhibited expression of the BMP signaling target gene Id, and induced the TGF-β target gene Lefty, whereas the opposite effect was observed with SB-431542. This study thus provides a new tool to investigate serotonergic differentiation and suggests that inhibition of BMP type I receptors and concomitant activation of TGF-β receptor signaling are implicated in serotonergic differentiation. Candidate-based screening for serotonergic induction using a rapid assay in mouse embryonic stem cells revealed that the bone morphogenetic protein (BMP) type I receptor kinase inhibitors selectively induce serotonergic differentiation, whereas the TGF-β receptor inhibitor SB-431542 inhibits the differentiation. These results suggest that inhibition of BMP type I receptors and concomitant activation of transforming growth factor-β (TGF-β) receptor signaling are involved in the early trajectory of serotonergic differentiation.
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Affiliation(s)
- Atsushi Yamasaki
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
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13
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Müller HK, Kragballe M, Fjorback AW, Wiborg O. Differential regulation of the serotonin transporter by vesicle-associated membrane protein 2 in cells of neuronal versus non-neuronal origin. PLoS One 2014; 9:e97540. [PMID: 24878716 PMCID: PMC4039532 DOI: 10.1371/journal.pone.0097540] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 04/21/2014] [Indexed: 11/30/2022] Open
Abstract
The serotonin transporter (SERT) is a key regulator of serotonergic signalling as it mediates the re-uptake of synaptic serotonin into nerve terminals, thereby terminating or modulating its signal. It is well-known that SERT regulation is a dynamic process orchestrated by a wide array of proteins and mechanisms. However, molecular details on possible coordinated regulation of SERT activity and 5-HT release are incomplete. Here, we report that vesicle-associated membrane protein 2 (VAMP2), a SNARE protein that mediates vesicle fusion with the plasma membrane, interacts with SERT. This was documented in vitro, through GST pull-down assays, by co-immunoprecipitation experiments on heterologous cells and rat hippocampal synaptosomes, and with FRET analysis in live transfected HEK-293 MSR cells. The related isoforms VAMP1 and VAMP3 also physically interact with SERT. However, comparison of the three VAMP isoforms shows that only VAMP2 possesses a functionally distinct role in relation to SERT. VAMP2 influences 5-HT uptake, cell surface expression and the delivery rate of SERT to the plasma membrane differentially in HEK-293 MSR and PC12 cells. Moreover, siRNA-mediated knock-down of endogenous VAMP2 reduces 5-HT uptake in CAD cells stably expressing low levels of heterologous SERT. Deletion and mutant analysis suggest a role for the isoform specific C-terminal domain of VAMP2 in regulating SERT function. Our data identify a novel interaction between SERT and a synaptic vesicle protein and support a link between 5-HT release and re-uptake.
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Affiliation(s)
- Heidi Kaastrup Müller
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University Hospital, Risskov, Denmark
| | - Marie Kragballe
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University Hospital, Risskov, Denmark
| | - Anja Winther Fjorback
- Stereology and Electron Microscopy Laboratory, Centre for Stochastic Geometry and Advanced Bioimaging, Department of Clinical Medicine, University of Aarhus, Aarhus, Denmark
| | - Ove Wiborg
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University Hospital, Risskov, Denmark
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14
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Ishihara K, Takahashi N, Komoto N, Yoshikawa C, Fukumoto S, Ide S, Kimura T, Ozawa K. Serotonergic modulation of neuronal activity in the nucleus accumbens following repeated methamphetamine administration in rats. J Pharmacol Sci 2013; 123:140-6. [PMID: 24096834 DOI: 10.1254/jphs.13100fp] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Electrophysiological studies were performed to determine whether serotonergic modulation in the nucleus accumbens (NAcc) was affected after repeated methamphetamine (MAP) administration. NAcc slices (400 μm) from Wistar rats administered MAP (5 mg/kg) or saline once daily for 5 days were prepared 1, 5, or 10 days after the final injection. Population spikes (PS) induced by local stimulation of NAcc were recorded. PS inhibition by serotonin was significantly attenuated in the MAP group at 5 days but did not differ at 1 or 10 days. We next analyzed the effects of serotonin receptor subtype (5-HT1A,2,3,4,6,7)-selective agonists of PS. Differences between saline and MAP groups in 5-HT1A,2,3,4,6 receptor agonist-induced changes of PS were small or not significant. Interestingly, 5-HT7 receptor agonists significantly enhanced PS in the MAP group. Changes in the secondary messenger system related to 5-HT7 receptors were also investigated. Adenylate cyclase activator-induced PS enhancements were significantly larger in the MAP group. However, dibutyryl-cAMP-induced PS enhancement was not significantly different. In conclusion, 5-HT-induced inhibition of PS in NAcc was attenuated 5 days after repeated MAP treatment: the change in the effect of 5-HT was probably due to enhancement of the excitatory modulation via the 5-HT7 receptor with adenylate cyclase signal transduction systems.
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Affiliation(s)
- Kumatoshi Ishihara
- Laboratory of Neuropharmacology, Faculty of Pharmaceutical Sciences, Hiroshima International University, Japan
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15
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Fujiwara M, Yamamoto H, Miyagi T, Seki T, Tanaka S, Hide I, Sakai N. Effects of the Chemical Chaperone 4-Phenylbutylate on the Function of the Serotonin Transporter (SERT) Expressed in COS-7 Cells. J Pharmacol Sci 2013; 122:71-83. [DOI: 10.1254/jphs.12194fp] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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