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Svec KV, Howe AK. Protein Kinase A in cellular migration—Niche signaling of a ubiquitous kinase. Front Mol Biosci 2022; 9:953093. [PMID: 35959460 PMCID: PMC9361040 DOI: 10.3389/fmolb.2022.953093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/30/2022] [Indexed: 12/28/2022] Open
Abstract
Cell migration requires establishment and maintenance of directional polarity, which in turn requires spatial heterogeneity in the regulation of protrusion, retraction, and adhesion. Thus, the signaling proteins that regulate these various structural processes must also be distinctly regulated in subcellular space. Protein Kinase A (PKA) is a ubiquitous serine/threonine kinase involved in innumerable cellular processes. In the context of cell migration, it has a paradoxical role in that global inhibition or activation of PKA inhibits migration. It follows, then, that the subcellular regulation of PKA is key to bringing its proper permissive and restrictive functions to the correct parts of the cell. Proper subcellular regulation of PKA controls not only when and where it is active but also specifies the targets for that activity, allowing the cell to use a single, promiscuous kinase to exert distinct functions within different subcellular niches to facilitate cell movement. In this way, understanding PKA signaling in migration is a study in context and in the elegant coordination of distinct functions of a single protein in a complex cellular process.
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Affiliation(s)
- Kathryn V. Svec
- Department of Pharmacology, University of Vermont, Burlington, VT, United States
| | - Alan K. Howe
- Department of Pharmacology, University of Vermont, Burlington, VT, United States
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, V T, United States
- University of Vermont Cancer Center, University of Vermont, Burlington, VT, United States
- *Correspondence: Alan K. Howe,
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2
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Horinouchi T, Miwa S. Comparison of cytotoxicity of cigarette smoke extract derived from heat-not-burn and combustion cigarettes in human vascular endothelial cells. J Pharmacol Sci 2021; 147:223-233. [PMID: 34507631 DOI: 10.1016/j.jphs.2021.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 07/06/2021] [Accepted: 07/20/2021] [Indexed: 11/30/2022] Open
Abstract
The present study compared the properties of mainstream smoke generated from heat-not-burn (HNB) cigarettes and a combustion cigarette (hi-lite™ brand). Three types of cigarette heating devices were used to generate cigarette smoke at different heating temperatures [Ploom S™ (200 °C), glo™ (240 °C), and IQOS™ (300-350 °C)]. Mainstream smoke was generated using the following puffing regimen: volume, 55 mL; duration, 3 s; and interval, 30 s. The rank order of particulate phase (nicotine and tar) amounts trapped on a Cambridge filter was Ploom S < glo < IQOS < hi-lite. Heated cigarette-derived smoke extract (hCSE) from the devices except for Ploom S, and burned CSE (bCSE) decreased mitochondrial metabolic activity (glo < IQOS < hi-lite) in human vascular endothelial cells. Furthermore, the cytotoxicity was reduced by removing the particulate phase from the mainstream smoke. Endothelial nitric oxide synthase activity was reduced by nicotine- and tar-free CSE of IQOS and hi-lite (IQOS < hi-lite), but not Ploom S and glo. These inhibitory effects were diminished by removing the carbonyl compounds from the mainstream smoke. These results indicated that the cytotoxicity of hCSE was lower than that of bCSE in vascular endothelial cells.
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Affiliation(s)
- Takahiro Horinouchi
- Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, North 15, West 7, Kita-ku, Sapporo, 060-8638, Japan.
| | - Soichi Miwa
- Toyooka General Hospital, 1094 Tobera, Toyooka, Hyogo, 668-8501, Japan
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3
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Abstract
Although the fighting behaviour in gamecocks has evolved because of artificial selection, it is unknown whether the selection for aggressiveness affects neurotransmitter levels in the avian central nervous system. We sought to identify the source and origin of this trait. We collected the brain samples from 6 female Shamo gamecocks and 5 Shaver Brown chickens (control; bred for egg production). The midbrain levels of norepinephrine (NE) were significantly higher in Shamo gamecocks (P = 0.0087) than in the controls. Moreover, alleles encoding adrenergic receptors differed between the breeds in terms of response to NE. Gene mutations specific to Shamo and potentially associated with fighting behaviour were in sites T440N of ADRα1D; V296I of ADRα2A; and T44I, Q232R, and T277M of ADRβ2. The evolutionary analysis indicated that the ADRβ2 (T44I and Q232R) mutations were heritable in all Galliformes, whereas the T440N mutation of ADRα1D and V296I mutations of ADRα2A were unique to Shamo and originated by artificial selection. A high NE level may confer a selective advantage by enabling gamecocks to be aggressive and pain tolerant. Therefore, the strong fighting behaviour of Shamo has resulted from a combination of naturally inherited and mutant genes derived by artificial selection.
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4
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Post-Translational Modification and Natural Mutation of TRPC Channels. Cells 2020; 9:cells9010135. [PMID: 31936014 PMCID: PMC7016788 DOI: 10.3390/cells9010135] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/03/2020] [Accepted: 01/03/2020] [Indexed: 02/06/2023] Open
Abstract
Transient Receptor Potential Canonical (TRPC) channels are homologues of Drosophila TRP channel first cloned in mammalian cells. TRPC family consists of seven members which are nonselective cation channels with a high Ca2+ permeability and are activated by a wide spectrum of stimuli. These channels are ubiquitously expressed in different tissues and organs in mammals and exert a variety of physiological functions. Post-translational modifications (PTMs) including phosphorylation, N-glycosylation, disulfide bond formation, ubiquitination, S-nitrosylation, S-glutathionylation, and acetylation play important roles in the modulation of channel gating, subcellular trafficking, protein-protein interaction, recycling, and protein architecture. PTMs also contribute to the polymodal activation of TRPCs and their subtle regulation in diverse physiological contexts and in pathological situations. Owing to their roles in the motor coordination and regulation of kidney podocyte structure, mutations of TRPCs have been implicated in diseases like cerebellar ataxia (moonwalker mice) and focal and segmental glomerulosclerosis (FSGS). The aim of this review is to comprehensively integrate all reported PTMs of TRPCs, to discuss their physiological/pathophysiological roles if available, and to summarize diseases linked to the natural mutations of TRPCs.
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5
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Whitcomb V, Wauson E, Christian D, Clayton S, Giles J, Tran QK. Regulation of beta adrenoceptor-mediated myocardial contraction and calcium dynamics by the G protein-coupled estrogen receptor 1. Biochem Pharmacol 2019; 171:113727. [PMID: 31759979 DOI: 10.1016/j.bcp.2019.113727] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 11/20/2019] [Indexed: 11/16/2022]
Abstract
The G protein-coupled estrogen receptor 1 (GPER) produces cardioprotective effects. However, the underlying mechanisms are not well understood. We aimed to investigate the role of GPER in β adrenoceptor-mediated cardiac contraction and myocardial signaling. In anesthetized animals, intrajugular administration of isoproterenol produces a rapid and sustained rise in left ventricular pressure (LVP) and increases ectopic contractions. Administration of the GPER agonist G-1 during the plateau phase of isoproterenol-induced LVP increase rapidly restores LVP to baseline levels and reduces the frequency of ectopic contractions. In freshly isolated cardiomyocytes, isoproterenol potentiates electrically induced peak currents of L-type Ca2+ channels (LTCC) and increases the potential sensitivity of their inactivation. Coadministration of G-1 prevents isoproterenol-induced potentiation of peak LTCC currents and makes channels more sensitive to being inactivated compared to isoproterenol alone. Isoproterenol treatment of cardiomyocytes without electrical stimulation triggers slow-rising Ca2+ signals that are inhibited by the β1AR antagonist metoprolol but not by β2AR antagonist ICI-118551. G-1 pretreatment dose-dependently suppresses isoproterenol-induced total Ca2+ signals and the amplitude and frequency of the intrinsic Ca2+ oscillatory deflections. Pretreatment with the GPER antagonist G-36 produces opposite effects, dose-dependently increasing these signals. ISO promotes robust phosphorylation of Cav1.2 channels at Ser1928. G-1 pretreatment inhibits isoproterenol-stimulated phosphorylation of Cav1.2 at Ser1928, while G-36 pretreatment enhances this signal. Our data indicate that GPER functions as an intrinsic component of β1AR signaling to moderate myocardial Ca2+ dynamics and contraction.
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Affiliation(s)
- Victoria Whitcomb
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States
| | - Eric Wauson
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States
| | - Daniel Christian
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States
| | - Sarah Clayton
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States
| | - Jennifer Giles
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States
| | - Quang-Kim Tran
- Department of Physiology and Pharmacology, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312, United States.
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Mihanfar A, Sadigh AR, Fattahi A, Latifi Z, Hasanzadeh-Moghadam M, Samadi M, Farzadi L, Hamdi K, Ghasemzadeh A, Nejabati HR, Nouri M. Endothelins and their receptors in embryo implantation. J Cell Biochem 2019; 120:14274-14284. [PMID: 31106465 DOI: 10.1002/jcb.28983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 03/31/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022]
Abstract
As a critical stage of pregnancy, the implantation of blastocysts into the endometrium is a progressive, excessively regulated local tissue remodeling step involving a complex sequence of genetic and cellular interplay executed within an optimal time frame. For better understanding the causes of infertility and, more importantly, for developing powerful strategies for successful implantations and combating infertility, an increasing number of recent studies have been focused on the identification and study of newly described substances in the reproductive tree. The endothelins (ET), a 21-aminoacidic family of genes, have been reported to be responsible for the contraction of vascular and nonvascular smooth muscles, including the smooth muscles of the uterus. Therefore, this review aims to comprehensively discuss the physiological role of endothelins and signaling through their receptors, as well as their probable involvement in the implantation process.
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Affiliation(s)
- Aynaz Mihanfar
- Department of Biochemistry, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran
| | - Aydin Raei Sadigh
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Fattahi
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zeinab Latifi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mahrokh Samadi
- Nephrology and Kidney Transplant Research Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Laya Farzadi
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Kobra Hamdi
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Aliyeh Ghasemzadeh
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Reza Nejabati
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Nouri
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Stem Cell and Regenerative Medicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
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7
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Komiyama T, Nagata E, Hashida T, Sakama S, Ayabe K, Kamiguchi H, Sasaki A, Yoshioka K, Kobayashi H. Neurally mediated syncope diagnosis based on adenylate cyclase activity in Japanese patients. PLoS One 2019; 14:e0214733. [PMID: 30998713 PMCID: PMC6472876 DOI: 10.1371/journal.pone.0214733] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 03/19/2019] [Indexed: 12/11/2022] Open
Abstract
The study aims to clarify the mechanism in patients with neurally mediated syncope (NMS), focusing on the adenylate cyclase (AC) activity level in lymphocytes. This study included 40 subjects: 22 healthy volunteers and 18 NMS patients. We investigated the changes in AC activity that occur during of syncope at rest and during the head-up tilt (HUT) test. We obtained 8 mL of blood at rest time and four times during the HUT test. Then, we measured the AC activity and the test reagent was added to the lymphocytes (10,000) and reacted for 30 min at room temperature. We were able to determine the standard value of AC activity when adrenaline (AD) and isoproterenol (IP) were added to lymphocytes. The results of our study showed one of the causes of NMS has a difference in AC activity level and classification of the patients into two different types of NMS was possible: either the vasodepressor type (VT) or mixed type (MT). At rest time, VT patients showed significantly higher AC activity (AD; 100 μM: p = 0.005, IP; 50 μM: p = 0.02) and MT patients showed significantly lower AC activity (AD; 10 μM: p = 0.02, IP; 50 μM: p = 0.004) than the average AC activity in healthy volunteers. Moreover, VT patients had significantly higher AC activity than healthy volunteers at the four points of the HUT test. MT patients had significantly lower AC activity (AD: p = 0.04 and IP: p = 0.04) than healthy volunteers at the rest time of HUT. Our study showed a significant difference in AC activities between NMS patients and healthy volunteers at rest. Therefore, a detailed NMS diagnosis can be made by examining AC activity levels in blood taken at rest time.
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Affiliation(s)
- Tomoyoshi Komiyama
- Department of Clinical Pharmacology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Eiichiro Nagata
- Department of Neurology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Tadashi Hashida
- Department of Cardiovascular Internal Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Susumu Sakama
- Department of Cardiovascular Internal Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Kengo Ayabe
- Department of Cardiovascular Internal Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Hiroshi Kamiguchi
- Support Center for Medical Research and Education, Tokai University, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Ayumi Sasaki
- Support Center for Medical Research and Education, Tokai University, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Koichiro Yoshioka
- Department of Cardiovascular Internal Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
| | - Hiroyuki Kobayashi
- Department of Clinical Pharmacology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, Japan
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8
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Strassheim D, Karoor V, Stenmark K, Verin A, Gerasimovskaya E. A current view of G protein-coupled receptor - mediated signaling in pulmonary hypertension: finding opportunities for therapeutic intervention. ACTA ACUST UNITED AC 2018; 2. [PMID: 31380505 PMCID: PMC6677404 DOI: 10.20517/2574-1209.2018.44] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pathological vascular remodeling is observed in various cardiovascular diseases including pulmonary hypertension (PH), a disease of unknown etiology that has been characterized by pulmonary artery vasoconstriction, right ventricular hypertrophy, vascular inflammation, and abnormal angiogenesis in pulmonary circulation. G protein-coupled receptors (GPCRs) are the largest family in the genome and widely expressed in cardiovascular system. They regulate all aspects of PH pathophysiology and represent therapeutic targets. We overview GPCRs function in vasoconstriction, vasodilation, vascular inflammation-driven remodeling and describe signaling cross talk between GPCR, inflammatory cytokines, and growth factors. Overall, the goal of this review is to emphasize the importance of GPCRs as critical signal transducers and targets for drug development in PH.
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Affiliation(s)
- Derek Strassheim
- Departments of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - Vijaya Karoor
- Departments of Medicine, University of Colorado Denver, Aurora, CO 80045, USA.,Cardiovascular and Pulmonary Research laboratories, University of Colorado Denver, Aurora, CO 80045, USA
| | - Kurt Stenmark
- Cardiovascular and Pulmonary Research laboratories, University of Colorado Denver, Aurora, CO 80045, USA.,Department of Pediatrics, Pulmonary and Critical Care Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - Alexander Verin
- Vascular Biology Center, Augusta University, Augusta, GA 30912, USA
| | - Evgenia Gerasimovskaya
- Cardiovascular and Pulmonary Research laboratories, University of Colorado Denver, Aurora, CO 80045, USA.,Department of Pediatrics, Pulmonary and Critical Care Medicine, University of Colorado Denver, Aurora, CO 80045, USA
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9
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Hao Y, Chow AW, Yip WC, Li CH, Wan TF, Tong BC, Cheung KH, Chan WY, Chen Y, Cheng CH, Ko WH. G protein-coupled estrogen receptor inhibits the P2Y receptor-mediated Ca(2+) signaling pathway in human airway epithelia. Pflugers Arch 2016; 468:1489-503. [PMID: 27271044 PMCID: PMC4951515 DOI: 10.1007/s00424-016-1840-7] [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: 01/21/2016] [Revised: 05/11/2016] [Accepted: 05/22/2016] [Indexed: 12/18/2022]
Abstract
P2Y receptor activation causes the release of inflammatory cytokines in the bronchial epithelium, whereas G protein-coupled estrogen receptor (GPER), a novel estrogen (E2) receptor, may play an anti-inflammatory role in this process. We investigated the cellular mechanisms underlying the inhibitory effect of GPER activation on the P2Y receptor-mediated Ca2+ signaling pathway and cytokine production in airway epithelia. Expression of GPER in primary human bronchial epithelial (HBE) or 16HBE14o- cells was confirmed on both the mRNA and protein levels. Stimulation of HBE or 16HBE14o- cells with E2 or G1, a specific agonist of GPER, attenuated the nucleotide-evoked increases in [Ca2+]i, whereas this effect was reversed by G15, a GPER-specific antagonist. G1 inhibited the secretion of two proinflammatory cytokines, interleukin (IL)-6 and IL-8, in cells stimulated by adenosine 5′-(γ-thio)triphosphate (ATPγS). G1 stimulated a real-time increase in cAMP levels in 16HBE14o- cells, which could be inhibited by adenylyl cyclase inhibitors. The inhibitory effects of E2 or G1 on P2Y receptor-induced increases in Ca2+ were reversed by treating the cells with a protein kinase A (PKA) inhibitor. These results demonstrated that the inhibitory effects of G1 or E2 on P2Y receptor-mediated Ca2+ mobilization and cytokine secretion were due to GPER-mediated activation of a cAMP-dependent PKA pathway. This study has reported, for the first time, the expression and function of GPER as an anti-inflammatory component in human bronchial epithelia, which may mediate through its opposing effects on the pro‐inflammatory pathway activated by the P2Y receptors in inflamed airway epithelia.
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Affiliation(s)
- Yuan Hao
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Alison W Chow
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Wallace C Yip
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Chi H Li
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Tai F Wan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Benjamin C Tong
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - King H Cheung
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Wood Y Chan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Yangchao Chen
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Christopher H Cheng
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong.
| | - Wing H Ko
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong.
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10
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Bouron A, Chauvet S, Dryer S, Rosado JA. Second Messenger-Operated Calcium Entry Through TRPC6. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:201-49. [PMID: 27161231 DOI: 10.1007/978-3-319-26974-0_10] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Canonical transient receptor potential 6 (TRPC6) proteins assemble into heteromultimeric structures forming non-selective cation channels. In addition, many TRPC6-interacting proteins have been identified like some enzymes, channels, pumps, cytoskeleton-associated proteins, immunophilins, or cholesterol-binding proteins, indicating that TRPC6 are engaged into macromolecular complexes. Depending on the cell type and the experimental conditions used, TRPC6 activity has been reported to be controlled by diverse modalities. For instance, the second messenger diacylglycerol, store-depletion, the plant extract hyperforin or H2O2 have all been shown to trigger the opening of TRPC6 channels. A well-characterized consequence of TRPC6 activation is the elevation of the cytosolic concentration of Ca(2+). This latter response can reflect the entry of Ca(2+) through open TRPC6 channels but it can also be due to the Na(+)/Ca(2+) exchanger (operating in its reverse mode) or voltage-gated Ca(2+) channels (recruited in response to a TRPC6-mediated depolarization). Although TRPC6 controls a diverse array of biological functions in many tissues and cell types, its pathophysiological functions are far from being fully understood. This chapter covers some key features of TRPC6, with a special emphasis on their biological significance in kidney and blood cells.
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Affiliation(s)
- Alexandre Bouron
- Université Grenoble Alpes, 38000, Grenoble, France. .,CNRS, iRTSV-LCBM, 38000, Grenoble, France.
| | - Sylvain Chauvet
- Université Grenoble Alpes, 38000, Grenoble, France.,CNRS, iRTSV-LCBM, 38000, Grenoble, France
| | - Stuart Dryer
- University of Houston, Houston, TX, USA.,Baylor College of Medicine, Houston, TX, USA
| | - Juan A Rosado
- Departamento de Fisiología, University of Extremadura, Cáceres, Spain
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11
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Horinouchi T, Terada K, Higashi T, Miwa S. Using Phos-Tag in Western Blotting Analysis to Evaluate Protein Phosphorylation. Methods Mol Biol 2016; 1397:267-277. [PMID: 26676139 DOI: 10.1007/978-1-4939-3353-2_18] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Protein phosphorylation has traditionally been detected by radioisotope phosphate labeling of proteins with radioactive ATP. Several nonradioactive assays with phosphorylation site-specific antibodies are now available for the analysis of phosphorylation status at target sites. However, due to their high specificity, these antibodies they cannot be used to detect unidentified phosphorylation sites. Recently, Phos-tag technology has been developed to overcome the disadvantages and limitations of phosphospecific antibodies. Phos-tag and its derivatives conjugated to biotin, acrylamide, or agarose, form alkoxide-bridged dinuclear metal complexes, which can capture phosphate monoester dianions bound to serine, threonine, and tyrosine residues, in an amino acid sequence-independent manner. Here, we describe our method, which is based on in vitro kinase assay and Western blotting analysis using biotinylated Phos-tag and horseradish peroxidase-conjugated streptavidin, to determine the sites of TRPC6 (transient receptor potential canonical 6) channel phosphorylated by protein kinase A.
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Affiliation(s)
- Takahiro Horinouchi
- Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Hokkaido, 060-8638, Japan.
| | - Koji Terada
- Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Hokkaido, 060-8638, Japan
| | - Tsunehito Higashi
- Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Hokkaido, 060-8638, Japan
| | - Soichi Miwa
- Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Hokkaido, 060-8638, Japan
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12
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Horinouchi T, Mazaki Y, Terada K, Higashi T, Miwa S. [Current progress in therapeutic agents for pulmonary arterial hypertension: new insights into their mechanisms of action from endothelin system]. Nihon Yakurigaku Zasshi 2016; 148:231-238. [PMID: 27803435 DOI: 10.1254/fpj.148.231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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13
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Weber EW, Han F, Tauseef M, Birnbaumer L, Mehta D, Muller WA. TRPC6 is the endothelial calcium channel that regulates leukocyte transendothelial migration during the inflammatory response. ACTA ACUST UNITED AC 2015; 212:1883-99. [PMID: 26392222 PMCID: PMC4612081 DOI: 10.1084/jem.20150353] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 08/25/2015] [Indexed: 12/14/2022]
Abstract
Weber et al. identify TRPC6 as the calcium channel mediating the transient increase in endothelial cytosolic free calcium concentration required for transendothelial migration of leukocytes during the inflammatory response. Leukocyte transendothelial migration (TEM) is a tightly regulated, multistep process that is critical to the inflammatory response. A transient increase in endothelial cytosolic free calcium ion concentration (↑[Ca2+]i) is required for TEM. However, the mechanism by which endothelial ↑[Ca2+]i regulates TEM and the channels mediating this ↑[Ca2+]i are unknown. Buffering ↑[Ca2+]i in endothelial cells does not affect leukocyte adhesion or locomotion but selectively blocks TEM, suggesting a role for ↑[Ca2+]i specifically for this step. Transient receptor potential canonical 6 (TRPC6), a Ca2+ channel expressed in endothelial cells, colocalizes with platelet/endothelial cell adhesion molecule-1 (PECAM) to surround leukocytes during TEM and clusters when endothelial PECAM is engaged. Expression of dominant-negative TRPC6 or shRNA knockdown in endothelial cells arrests neutrophils apically over the junction, similar to when PECAM is blocked. Selectively activating endothelial TRPC6 rescues TEM during an ongoing PECAM blockade, indicating that TRPC6 functions downstream of PECAM. Furthermore, endothelial TRPC6 is required for trafficking of lateral border recycling compartment membrane, which facilitates TEM. Finally, mice lacking TRPC6 in the nonmyeloid compartment (i.e., endothelium) exhibit a profound defect in neutrophil TEM with no effect on leukocyte trafficking. Our findings identify endothelial TRPC6 as the calcium channel mediating the ↑[Ca2+]i required for TEM at a step downstream of PECAM homophilic interactions.
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Affiliation(s)
- Evan W Weber
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Fei Han
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Mohammad Tauseef
- Department of Pharmacology, Center for Lung and Vascular Biology, University of Illinois in Chicago College of Medicine, Chicago, IL 60612
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
| | - Dolly Mehta
- Department of Pharmacology, Center for Lung and Vascular Biology, University of Illinois in Chicago College of Medicine, Chicago, IL 60612
| | - William A Muller
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
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14
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Terada K, Horinouchi T, Fujioka Y, Higashi T, Nepal P, Horiguchi M, Karki S, Hatate C, Hoshi A, Harada T, Mai Y, Ohba Y, Miwa S. Agonist-promoted ubiquitination differentially regulates receptor trafficking of endothelin type A and type B receptors. J Biol Chem 2014; 289:35283-95. [PMID: 25381251 DOI: 10.1074/jbc.m113.544171] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Two types of G protein-coupled receptors for endothelin-1 (ET-1), ET type A receptor (ETAR) and ETBR, closely resemble each other, but upon ET-1 stimulation, they follow totally different intracellular trafficking pathways; ETAR is recycled back to plasma membrane, whereas ETBR is targeted to lysosome for degradation. However, the mechanisms for such different fates are unknown. Here we demonstrated that ETBR but not ETAR was ubiquitinated on the cell surface following ET-1 stimulation and that ETBR was internalized and degraded in lysosome more rapidly than ETAR. The mutant ETBR (designated "5KR mutant") in which 5 lysine residues in the C-tail were substituted to arginine was not ubiquitinated, and its rates of internalization and degradation after ET-1 stimulation became slower, being comparable with those of ETAR. Confocal microscopic study showed that following ET-1 stimulation, ETAR and 5KR mutant of ETBR were co-localized mainly with Rab11, a marker of recycling endosome, whereas ETBR was co-localized with Rab7, a marker of late endosome/lysosome. In the 5KR mutant, ET-1-induced ERK phosphorylation and an increase in the intracellular Ca(2+) concentration upon repetitive ET-1 stimulation were larger. A series of ETBR mutants (designated "4KR mutant"), in which either one of 5 arginine residues of the 5KR mutant was reverted to lysine, were normally ubiquitinated, internalized, and degraded, with ERK phosphorylation being normalized. These results demonstrate that agonist-induced ubiquitination at either lysine residue in the C-tail of ETBR but not ETAR switches intracellular trafficking from recycling to plasma membrane to targeting to lysosome, causing decreases in the cell surface level of ETBR and intracellular signaling.
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Affiliation(s)
- Koji Terada
- From the Departments of Cellular Pharmacology and
| | | | - Yoichiro Fujioka
- Cell Physiology, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo 060-8638, Japan
| | | | - Prabha Nepal
- From the Departments of Cellular Pharmacology and
| | | | - Sarita Karki
- From the Departments of Cellular Pharmacology and
| | | | | | | | - Yosuke Mai
- From the Departments of Cellular Pharmacology and
| | - Yusuke Ohba
- Cell Physiology, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo 060-8638, Japan
| | - Soichi Miwa
- From the Departments of Cellular Pharmacology and
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15
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Sodhi P, Hartwick ATE. Adenosine modulates light responses of rat retinal ganglion cell photoreceptors througha cAMP-mediated pathway. J Physiol 2014; 592:4201-20. [PMID: 25038240 DOI: 10.1113/jphysiol.2014.276220] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Adenosine is an established neuromodulator in the mammalian retina, with A1 adenosine receptors being especially prevalent in the innermost ganglion cell layer. Activation of A1 receptors causes inhibition of adenylate cyclase, decreases in intracellular cyclic AMP (cAMP) levels and inhibition of protein kinase A (PKA). In this work, our aim was to characterize the effects of adenosine on the light responses of intrinsically photosensitive retinal ganglion cells (ipRGCs) and to determine whether these photoreceptors are subject to neuromodulation through intracellular cAMP-related signalling pathways. Using multielectrode array recordings from postnatal and adult rat retinas, we demonstrated that adenosine significantly shortened the duration of ipRGC photoresponses and reduced the number of light-evoked spikes fired by these neurons. The effects were A1 adenosine receptor-mediated, and the expression of this receptor on melanopsin-containing ipRGCs was confirmed by calcium imaging experiments on isolated cells in purified cultures. While inhibition of the cAMP/PKA pathway by adenosine shortened ipRGC light responses, stimulation of this pathway with compounds such as forskolin had the opposite effect and lengthened the duration of ipRGC spiking. Our findings reveal that the modification of ipRGC photoresponses through a cAMP/PKA pathway is a general feature of rat ganglion cell photoreceptors, and this pathway can be inhibited through activation of A1 receptors by adenosine. As adenosine levels in the retina rise at night, adenosinergic modulation of ipRGCs may serve as an internal regulatory mechanism to limit transmission of nocturnal photic signals by ipRGCs to the brain. Targeting retinal A1 adenosine receptors for ipRGC inhibition represents a potential therapeutic target for sleep disorders and migraine-associated photophobia.
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Affiliation(s)
- Puneet Sodhi
- Department of Neuroscience, Ohio State University, Columbus, OH, 43210, USA
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16
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cAMP and Ca²⁺ signaling in secretory epithelia: crosstalk and synergism. Cell Calcium 2014; 55:385-93. [PMID: 24613710 DOI: 10.1016/j.ceca.2014.01.006] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 01/29/2014] [Accepted: 01/30/2014] [Indexed: 12/15/2022]
Abstract
The Ca(2+) and cAMP/PKA pathways are the primary signaling systems in secretory epithelia that control virtually all secretory gland functions. Interaction and crosstalk in Ca(2+) and cAMP signaling occur at multiple levels to control and tune the activity of each other. Physiologically, Ca(2+) and cAMP signaling operate at 5-10% of maximal strength, but synergize to generate the maximal response. Although synergistic action of the Ca(2+) and cAMP signaling is the common mode of signaling and has been known for many years, we know very little of the molecular mechanism and mediators of the synergism. In this review, we discuss crosstalk between the Ca(2+) and cAMP signaling and the function of IRBIT (IP3 receptors binding protein release with IP3) as a third messenger that mediates the synergistic action of the Ca(2+) and cAMP signaling.
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17
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Chiluiza D, Krishna S, Schumacher VA, Schlöndorff J. Gain-of-function mutations in transient receptor potential C6 (TRPC6) activate extracellular signal-regulated kinases 1/2 (ERK1/2). J Biol Chem 2013; 288:18407-20. [PMID: 23645677 DOI: 10.1074/jbc.m113.463059] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Gain-of-function mutations in the canonical transient receptor potential 6 (TRPC6) gene are a cause of autosomal dominant focal segmental glomerulosclerosis (FSGS). The mechanisms whereby abnormal TRPC6 activity results in proteinuria remain unknown. The ERK1/2 MAPKs are activated in glomeruli and podocytes in several proteinuric disease models. We therefore examined whether FSGS-associated mutations in TRPC6 result in activation of these kinases. In 293T cells and cultured podocytes, overexpression of gain-of-function TRPC6 mutants resulted in increased ERK1/2 phosphorylation, an effect dependent upon channel function. Pharmacologic inhibitor studies implicated several signaling mediators, including calmodulin and calcineurin, supporting the importance of TRPC6-mediated calcium influx in this process. Through medium transfer experiments, we uncovered two distinct mechanisms for ERK activation by mutant TRPC6, a cell-autonomous, EGF receptor-independent mechanism and a non-cell-autonomous mechanism involving metalloprotease-mediated release of a presumed EGF receptor ligand. The inhibitors KN-92 and H89 were able to block both pathways in mutant TRPC6 expressing cells as well as the prolonged elevation of intracellular calcium levels upon carbachol stimulation seen in these cells. However, these effects appear to be independent of their effects on calcium/calmodulin-dependent protein kinase II and PKA, respectively. Phosphorylation of Thr-70, Ser-282, and Tyr-31/285 were not necessary for ERK activation by mutant TRPC6, although a phosphomimetic TRPC6 S282E mutant was capable of ERK activation. Taken together, these results identify two pathways downstream of mutant TRPC6 leading to ERK activation that may play a role in the development of FSGS.
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Affiliation(s)
- David Chiluiza
- Division of Nephrology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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18
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Horinouchi T, Terada K, Higashi T, Miwa S. Endothelin Receptor Signaling: New Insight Into Its Regulatory Mechanisms. J Pharmacol Sci 2013; 123:85-101. [DOI: 10.1254/jphs.13r02cr] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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19
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Tabarean IV. Persistent histamine excitation of glutamatergic preoptic neurons. PLoS One 2012; 7:e47700. [PMID: 23082195 PMCID: PMC3474751 DOI: 10.1371/journal.pone.0047700] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 09/17/2012] [Indexed: 12/17/2022] Open
Abstract
Thermoregulatory neurons of the median preoptic nucleus (MnPO) represent a target at which histamine modulates body temperature. The mechanism by which histamine excites a population of MnPO neurons is not known. In this study it was found that histamine activated a cationic inward current and increased the intracellular Ca(2+) concentration, actions that had a transient component as well as a sustained one that lasted for tens of minutes after removal of the agonist. The sustained component was blocked by TRPC channel blockers. Single-cell reverse transcription-PCR analysis revealed expression of TRPC1, TRPC5 and TRPC7 subunits in neurons excited by histamine. These studies also established the presence of transcripts for the glutamatergic marker Vglut2 and for the H1 histamine receptor in neurons excited by histamine. Intracellular application of antibodies directed against cytoplasmic sites of the TRPC1 or TRPC5 channel subunits decreased the histamine-induced inward current. The persistent inward current and elevation in intracellular Ca(2+) concentration could be reversed by activating the PKA pathway. This data reveal a novel mechanism by which histamine induces persistent excitation and sustained intracellular Ca(2+) elevation in glutamatergic MnPO neurons.
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Affiliation(s)
- Iustin V Tabarean
- The Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, La Jolla, California, USA.
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20
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Horinouchi T, Higashi T, Higa T, Terada K, Mai Y, Aoyagi H, Hatate C, Nepal P, Horiguchi M, Harada T, Miwa S. Different binding property of STIM1 and its novel splice variant STIM1L to Orai1, TRPC3, and TRPC6 channels. Biochem Biophys Res Commun 2012; 428:252-8. [PMID: 23068106 DOI: 10.1016/j.bbrc.2012.10.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 10/05/2012] [Indexed: 01/16/2023]
Abstract
Stromal interaction molecule 1 (STIM1) is the endoplasmic reticulum (ER) Ca(2+) sensor to control ER Ca(2+) levels. A recent study has shown that STIM1L, a new splice variant of STIM1, is expressed in various tissues of rodent and in human skeletal muscle, and that the interaction of STIM1L with actin filament allows rapid activation of store-operated Ca(2+) entry (SOCE) mediated through Orai1 channels. Here, we characterize mRNA expression and function of human STIM1 and STIM1L, and compare their binding property to Orai1 functioning as store-operated Ca(2+) channels (SOCCs), and TRPC3 (transient receptor potential canonical 3) and TRPC6 channels functioning as endothelin type A receptor (ET(A)R)-operated Ca(2+) channels (ROCCs). Although mRNA for STIM1 was ubiquitously expressed in human tissues, STIM1L was detected only in skeletal muscle. STIM1L augmented thapsigargin- and endothelin-1-induced SOCE more strongly than STIM1 in human embryonic kidney 293 cells stably expressing ET(A)R, whereas, it tends to suppress ET(A)R-operated Ca(2+) entry (ROCE) via TRPC3 and TRPC6 more strongly than STIM1. Coimmunoprecipitation experiments have revealed that when compared with STIM1, STIM1L binds more abundantly to Orai1 and also to TRPC3 and TRPC6. These results suggest that the higher binding capacity of STIM1L to SOCCs and ROCCs plays an important role in the regulation of Ca(2+) signaling such as the augmentation of SOCE via Orai1 and the inhibition of ROCE via TRPC3 and TRPC6.
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Affiliation(s)
- Takahiro Horinouchi
- Department of Cellular Pharmacology, Hokkaido University Graduate School of Medicine, Hokkaido 060-8638, Japan.
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21
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Kinoshita E, Kinoshita-Kikuta E, Sugiyama Y, Fukada Y, Ozeki T, Koike T. Highly sensitive detection of protein phosphorylation by using improved Phos-tag Biotin. Proteomics 2012; 12:932-7. [DOI: 10.1002/pmic.201100639] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Eiji Kinoshita
- Department of Functional Molecular Science; Graduate School of Biomedical Sciences; Hiroshima University; Hiroshima; Japan
| | - Emiko Kinoshita-Kikuta
- Department of Functional Molecular Science; Graduate School of Biomedical Sciences; Hiroshima University; Hiroshima; Japan
| | - Yasunori Sugiyama
- Department of Biophysics and Biochemistry; Graduate School of Science; The University of Tokyo; Tokyo; Japan
| | - Yoshitaka Fukada
- Department of Biophysics and Biochemistry; Graduate School of Science; The University of Tokyo; Tokyo; Japan
| | | | - Tohru Koike
- Department of Functional Molecular Science; Graduate School of Biomedical Sciences; Hiroshima University; Hiroshima; Japan
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22
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Mai Y, Higashi T, Terada K, Hatate C, Nepal P, Horiguchi M, Harada T, Miwa S, Horinouchi T. Nicotine- and Tar-free Cigarette Smoke Extract Induces Cell Injury via Intracellular Ca2+-Dependent Subtype-Specific Protein Kinase C Activation. J Pharmacol Sci 2012; 120:310-4. [DOI: 10.1254/jphs.12219sc] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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23
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Seifert R, Lushington GH, Mou TC, Gille A, Sprang SR. Inhibitors of membranous adenylyl cyclases. Trends Pharmacol Sci 2011; 33:64-78. [PMID: 22100304 DOI: 10.1016/j.tips.2011.10.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 10/18/2011] [Accepted: 10/19/2011] [Indexed: 12/11/2022]
Abstract
Membranous adenylyl cyclases (mACs) constitute a family of nine isoforms with different expression patterns. Studies with mAC gene knockout mice provide evidence for the notion that AC isoforms play distinct (patho)physiological roles. Consequently, there is substantial interest in the development of isoform-selective mAC inhibitors. Here, we review the current literature on mAC inhibitors. Structurally diverse inhibitors targeting the catalytic site and allosteric sites (e.g. the diterpene site) have been identified. The catalytic site of mACs accommodates both purine and pyrimidine nucleotides, with a hydrophobic pocket constituting a major affinity-conferring domain for substituents at the 2'- and 3'-O-ribosyl position of nucleotides. BODIPY-forskolin stimulates ACs 1 and 5 but inhibits AC2. However, so far, no inhibitor has been examined at all mAC isoforms, and data obtained with mAC inhibitors in intact cells have not always been interpreted cautiously enough. Future strategies for the development of the mAC inhibitor field are discussed critically.
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Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany.
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