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Wang Y, Galli M, Shade Silver A, Lee W, Song Y, Mei Y, Bachus C, Glogauer M, McCulloch CA. IL1β and TNFα promote RANKL-dependent adseverin expression and osteoclastogenesis. J Cell Sci 2018; 131:jcs.213967. [PMID: 29724913 DOI: 10.1242/jcs.213967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 04/23/2018] [Indexed: 12/20/2022] Open
Abstract
Adseverin is an actin-binding protein involved in osteoclastogenesis, but its role in inflammation-induced bone loss is not well-defined. Here, we examined whether IL1β and TNFα regulate adseverin expression to control osteoclastogenesis in mouse primary monocytes and RAW264.7 cells. Adseverin was colocalized with subcortical actin filaments and was enriched in the fusopods of fusing cells. In precursor cells, adseverin overexpression boosted the formation of RANKL-induced multinucleated cells. Both IL1β and TNFα enhanced RANKL-dependent TRAcP activity by 1.6-fold and multinucleated cell formation (cells with ≥3 nuclei) by 2.6- and 3.3-fold, respectively. However, IL1β and TNFα did not enhance osteoclast formation in adseverin-knockdown cells. RANKL-dependent adseverin expression in bone marrow cells was increased by both IL1β (5.4-fold) and TNFα (3.3-fold). Luciferase assays demonstrated that this expression involved transcriptional regulation of the adseverin promoter. Activation of the promoter was restricted to a 1118 bp sequence containing an NF-κB binding site, upstream of the transcription start site. TNFα also promoted RANKL-induced osteoclast precursor cell migration. We conclude that IL1β and TNFα enhance RANKL-dependent expression of adseverin, which contributes to fusion processes in osteoclastogenesis.
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Affiliation(s)
- Yongqiang Wang
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Matthew Galli
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Alexandra Shade Silver
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Wilson Lee
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Yushan Song
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Yixue Mei
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Carly Bachus
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Michael Glogauer
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
| | - Christopher A McCulloch
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, M5S 3E2
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Wang J, Richards DA. The actin binding protein scinderin acts in PC12 cells to tether dense-core vesicles prior to secretion. Mol Cell Neurosci 2017; 85:12-18. [PMID: 28823945 DOI: 10.1016/j.mcn.2017.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/07/2017] [Accepted: 08/16/2017] [Indexed: 11/18/2022] Open
Abstract
Mechanistic understanding of the control of vesicle motion from within a secretory cell to the site of exocytosis remains incomplete. In this work, we have used total internal reflection (TIRF) microscopy to examine the mobility of secretory vesicles at the plasma membrane. Under resting conditions, we found vesicles showed little lateral mobility. Anchoring of vesicles in this membrane proximal compartment could be disrupted with latrunculin A, indicating an apparent actin dependent process. A candidate intermediary between vesicles and the actin skeleton is the actin binding protein scinderin. Co-transfection of an shRNA construct against scinderin blocked secretion, and also increased the mobility of vesicles in the membrane-proximal section of the cell, indicating a dual role for scinderin in secretion; tethering vesicles to the cytoskeleton, as well as liberating them following stimulation through the previously described calcium dependent actin severing activity. Analysis of lipid dependence indicates that scinderin exhibits calcium dependent binding to phosphatidyl-inositol monophosphate, providing a possible mechanism for vesicle binding.
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Affiliation(s)
- J Wang
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, MLC2001, 3333 Burnet Avenue, Cincinnati, OH 45229, United States
| | - D A Richards
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, MLC2001, 3333 Burnet Avenue, Cincinnati, OH 45229, United States; Department of Basic Pharmaceutical Sciences, Husson University School of Pharmacy, 1 College Circle, Bangor, ME 04401, United States.
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3
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Cárdenas AM, Marengo FD. How the stimulus defines the dynamics of vesicle pool recruitment, fusion mode, and vesicle recycling in neuroendocrine cells. J Neurochem 2016; 137:867-79. [DOI: 10.1111/jnc.13565] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Revised: 01/05/2016] [Accepted: 01/25/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Ana María Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso; Universidad de Valparaíso; Valparaíso Chile
| | - Fernando D. Marengo
- Laboratorio de Fisiología y Biología Molecular; Instituto de Fisiología; Biología Molecular y Neurociencias (CONICET); Departamento de Fisiología y Biología Molecular y Celular; Facultad de Ciencias Exactas y Naturales; Universidad de Buenos Aires; Buenos Aires Argentina
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Hassanpour S, Jiang H, Wang Y, Kuiper JWP, Glogauer M. The actin binding protein adseverin regulates osteoclastogenesis. PLoS One 2014; 9:e109078. [PMID: 25275604 PMCID: PMC4183545 DOI: 10.1371/journal.pone.0109078] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 09/07/2014] [Indexed: 11/29/2022] Open
Abstract
Adseverin (Ads), a member of the Gelsolin superfamily of actin binding proteins, regulates the actin cytoskeleton architecture by severing and capping existing filamentous actin (F-actin) strands and nucleating the assembly of new F-actin filaments. Ads has been implicated in cellular secretion, exocytosis and has also been shown to regulate chondrogenesis and megakaryoblastic leukemia cell differentiation. Here we report for the first time that Ads is involved in regulating osteoclastogenesis (OCG). Ads is induced during OCG downstream of RANK-ligand (RANKL) stimulation and is highly expressed in mature osteoclasts. The D5 isoform of Ads is not involved in regulating OCG, as its expression is not induced in response to RANKL. Three clonal Ads knockdown RAW264.7 (RAW) macrophage cell lines with varying degrees of Ads expression and OCG deficiency were generated. The most drastic OCG defect was noted in the clonal cell line with the greatest degree of Ads knockdown as indicated by a lack of TRAcP staining and multinucleation. RNAi mediated knockdown of Ads in osteoclast precursors resulted in distinct morphological changes characterized by altered F-actin distribution and increased filopodia formation. Ads knockdown precursor cells experienced enhanced migration while fusion of knockdown precursors cells was limited. Transient reintroduction of de novo Ads back into the knockdown system was capable of rescuing TRAcP expression but not osteoclast multinucleation most likely due to the transient nature of Ads expression. This preliminary study allows us to conclude that Ads is a RANKL induced early regulator of OCG with a potential role in pre-osteoclast differentiation and fusion.
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Affiliation(s)
- Siavash Hassanpour
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - Hongwei Jiang
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, P. R. China
| | - Yongqiang Wang
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - Johannes W. P. Kuiper
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - Michael Glogauer
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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Isgandarova S, Jones L, Forsberg D, Loncar A, Dawson J, Tedrick K, Eitzen G. Stimulation of actin polymerization by vacuoles via Cdc42p-dependent signaling. J Biol Chem 2007; 282:30466-75. [PMID: 17726018 DOI: 10.1074/jbc.m704117200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously shown that actin ligands inhibit the fusion of yeast vacuoles in vitro, which suggests that actin remodeling is a subreaction of membrane fusion. Here, we demonstrate the presence of vacuole-associated actin polymerization activity, and its dependence on Cdc42p and Vrp1p. Using a sensitive in vitro pyrene-actin polymerization assay, we found that vacuole membranes stimulated polymerization, and this activity increased when vacuoles were preincubated under conditions that support membrane fusion. Vacuoles purified from a VRP1-gene deletion strain showed reduced polymerization activity, which could be recovered when reconstituted with excess Vrp1p. Cdc42p regulates this activity because overexpression of dominant-negative Cdc42p significantly reduced vacuole-associated polymerization activity, while dominant-active Cdc42p increased activity. We also used size-exclusion chromatography to directly examine changes in yeast actin induced by vacuole fusion. This assay confirmed that actin undergoes polymerization in a process requiring ATP. To further confirm the need for actin polymerization during vacuole fusion, an actin polymerization-deficient mutant strain was examined. This strain showed in vivo defects in vacuole fusion, and actin purified from this strain inhibited in vitro vacuole fusion. Affinity isolation of vacuole-associated actin and in vitro binding assays revealed a polymerization-dependent interaction between actin and the SNARE Ykt6p. Our results suggest that actin polymerization is a subreaction of vacuole membrane fusion governed by Cdc42p signal transduction.
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Affiliation(s)
- Sabina Isgandarova
- Department of Cell Biology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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Ono S. Mechanism of depolymerization and severing of actin filaments and its significance in cytoskeletal dynamics. INTERNATIONAL REVIEW OF CYTOLOGY 2007; 258:1-82. [PMID: 17338919 DOI: 10.1016/s0074-7696(07)58001-0] [Citation(s) in RCA: 212] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The actin cytoskeleton is one of the major structural components of the cell. It often undergoes rapid reorganization and plays crucial roles in a number of dynamic cellular processes, including cell migration, cytokinesis, membrane trafficking, and morphogenesis. Actin monomers are polymerized into filaments under physiological conditions, but spontaneous depolymerization is too slow to maintain the fast actin filament dynamics observed in vivo. Gelsolin, actin-depolymerizing factor (ADF)/cofilin, and several other actin-severing/depolymerizing proteins can enhance disassembly of actin filaments and promote reorganization of the actin cytoskeleton. This review presents advances as well as a historical overview of studies on the biochemical activities and cellular functions of actin-severing/depolymerizing proteins.
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Affiliation(s)
- Shoichiro Ono
- Department of Pathology, Emory University, Atlanta, GA 30322, USA
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Dumitrescu Pene T, Rosé SD, Lejen T, Marcu MG, Trifaró JM. Expression of various scinderin domains in chromaffin cells indicates that this protein acts as a molecular switch in the control of actin filament dynamics and exocytosis. J Neurochem 2005; 92:780-9. [PMID: 15686479 DOI: 10.1111/j.1471-4159.2004.02907.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Stimulation-induced chromaffin cell cortical F-actin disassembly allows the movement of vesicles towards exocytotic sites. Scinderin (Sc), a Ca2+-dependent protein, controls actin dynamics. Sc six domains have three actin, two PIP2 and two Ca2+-binding sites. F-actin severing activity of Sc is Ca2+-dependent, whereas Sc-evoked actin nucleation is Ca2+-independent. Sc domain role in secretion was studied by co-transfection of human growth hormone (hGH) reporter gene and green fluorescent protein (GFP)-fusion Sc constructs. Cells over-expressing actin severing Sc1-6 or Sc1-2 (first and second actin binding sites) constructs, increased F-actin disassembly and hGH release upon depolarization. Over-expression of nucleating Sc5-6, Sc5 or ScABP3 (third actin site) constructs decreased F-actin disassembly and hGH release upon stimulation. Over-expression of ScL5-6 or ScL5 (lack of third actin site) produced no changes. During secretion, actin sites 1 and 2 are involved in F-actin severing, whereas site 3 is responsible for nucleation (polymerization). Sc functions as a molecular switch in the control of actin (disassembly left arrow over right arrow assembly) and release (facilitation left arrow over right arrow inhibition). The position of the switch (severing left arrow over right arrow nucleation) may be controlled by [Ca2+]i. Thus, increase in [Ca2+]i produced by stimulation-induced Ca2+ entry would increase Sc-evoked cortical F-actin disassembly. Decrease in [Ca2+]i by either organelle sequestration or cell extrusion would favor Sc-evoked actin nucleation.
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Affiliation(s)
- Teodora Dumitrescu Pene
- Secretory Process Research Program, Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ontario, Canada
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Ikeda M, Suzuki S, Kishio M, Hirono M, Sugiyama T, Matsuura J, Suzuki T, Sota T, Allen CN, Konishi S, Yoshioka T. Hydrogen-deuterium exchange effects on beta-endorphin release from AtT20 murine pituitary tumor cells. Biophys J 2004; 86:565-75. [PMID: 14695301 PMCID: PMC1303825 DOI: 10.1016/s0006-3495(04)74135-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abundant evidences demonstrate that deuterium oxide (D2O) modulates various secretory activities, but specific mechanisms remain unclear. Using AtT20 cells, we examined effects of D2O on physiological processes underlying beta-endorphin release. Immunofluorescent confocal microscopy demonstrated that 90% D2O buffer increased the amount of actin filament in cell somas and decreased it in cell processes, whereas beta-tubulin was not affected. Ca2+ imaging demonstrated that high-K+-induced Ca2+ influx was not affected during D2O treatment, but was completely inhibited upon D2O washout. The H2O/D2O replacement in internal solutions of patch electrodes reduced Ca2+ currents evoked by depolarizing voltage steps, whereas additional extracellular H2O/D2O replacement recovered the currents, suggesting that D2O gradient across plasma membrane is critical for Ca2+ channel kinetics. Radioimmunoassay of high-K+-induced beta-endorphin release demonstrated an increase during D2O treatment and a decrease upon D(2)O washout. These results demonstrate that the H2O-to-D2O-induced increase in beta-endorphin release corresponded with the redistribution of actin, and the D2O-to-H2O-induced decrease in beta-endorphin release corresponded with the inhibition of voltage-sensitive Ca2+ channels. The computer modeling suggests that the differences in the zero-point vibrational energy between protonated and deuterated amino acids produce an asymmetric distribution of these amino acids upon D2O washout and this causes the dysfunction of Ca2+ channels.
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Affiliation(s)
- Masayuki Ikeda
- Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo Shinjuku-ku, Tokyo 169-8555, Japan
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9
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Abstract
Regulated exocytosis of secretory granules or dense-core granules has been examined in many well-characterized cell types including neurons, neuroendocrine, endocrine, exocrine, and hemopoietic cells and also in other less well-studied cell types. Secretory granule exocytosis occurs through mechanisms with many aspects in common with synaptic vesicle exocytosis and most likely uses the same basic protein components. Despite the widespread expression and conservation of a core exocytotic machinery, many variations occur in the control of secretory granule exocytosis that are related to the specialized physiological role of particular cell types. In this review we describe the wide range of cell types in which regulated secretory granule exocytosis occurs and assess the evidence for the expression of the conserved fusion machinery in these cells. The signals that trigger and regulate exocytosis are reviewed. Aspects of the control of exocytosis that are specific for secretory granules compared with synaptic vesicles or for particular cell types are described and compared to define the range of accessory control mechanisms that exert their effects on the core exocytotic machinery.
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Affiliation(s)
- Robert D Burgoyne
- The Physiological Laboratory, University of Liverpool, United Kingdom.
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10
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Rosé SD, Lejen T, Casaletti L, Larson RE, Pene TD, Trifaró JM. Myosins II and V in chromaffin cells: myosin V is a chromaffin vesicle molecular motor involved in secretion. J Neurochem 2003; 85:287-98. [PMID: 12675905 DOI: 10.1046/j.1471-4159.2003.01649.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The presence of myosin II and V in chromaffin cells and their subcellular distribution is described. Myosin II and V distribution in sucrose density gradients showed only a strong correlation between the distribution of myosin V and secretory vesicle markers. Confocal microscopy images demonstrated colocalization of myosin V with dopamine beta-hydroxylase, a chromaffin vesicle marker, whereas myosin II was present mainly in the cell cortex. Cell depolarization induced, in a Ca2+ and time-dependent manner, the dissociation of myosin V from chromaffin vesicles suggesting that this association was not permanent but determined by secretory cycle requirements. Myosin II was also found in the crude granule fraction, however, its distribution was not affected by cell depolarization. Myosin V head antibodies were able to inhibit secretion whereas myosin II antibodies had no inhibitory effect. The pattern of inhibition indicated that these treatments interfered with the transport of vesicles from the reserve to the release-ready compartment, suggesting the involvement of myosin V and not myosin II in this transport process. The results described here suggest that myosin V is a molecular motor involved in chromaffin vesicle secretion. However, these results do not discard an indirect role for myosin II in secretion through its interaction with F-actin networks.
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Affiliation(s)
- Sergio D Rosé
- Secretory Process Research Program, Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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Trifaró JM, Lejen T, Rosé SD, Pene TD, Barkar ND, Seward EP. Pathways that control cortical F-actin dynamics during secretion. Neurochem Res 2002; 27:1371-85. [PMID: 12512942 DOI: 10.1023/a:1021627800918] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Chromaffin cells possess a mesh of filamentous actin underneath the plasma membrane which acts as a barrier to the chromaffin vesicles access to exocytotic sites. Disassembly of cortical F-actin in response to stimulation allows the movement of vesicles from the reserve pool to the release-ready vesicle pool and, therefore, to exocytotic sites. The dynamics of cortical F-actin is controlled by two mechanisms: a) stimulation-induced Ca2+ entry and scinderin activation and b) protein kinase C (PKC) activation and MARCKS phosphorylation as demonstrated here by experiments with recombinant proteins, antisense olygodeoxynucleotides and vector mediated transient expressions. Under physiological conditions (i.e., cholinergic receptor stimulation followed by Ca2+ entry), mechanism (a) is the most important for the control of cortical F-actin network whereas when Ca2+ is released from intracellular stores (i.e., histamine stimulation) cortical F-actin is regulated mainly by mechanism b.
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Affiliation(s)
- J M Trifaró
- Secretory Process Research Program, Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ontario, Canada K1H 8M5.
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Lejen T, Pene TD, Rosé SD, Trifaró JM. The role of different Scinderin domains in the control of F-actin cytoskeleton during exocytosis. Ann N Y Acad Sci 2002; 971:248-50. [PMID: 12438125 DOI: 10.1111/j.1749-6632.2002.tb04469.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Scinderin (Sc), a Ca(2+)-regulated actin-binding protein, has been previously shown to control submembranous actin dynamics in regulated secretion. The results of the present study suggest the possibility that Sc might act as a molecular switch in the control of cortical F-actin dynamics during secretion.
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Affiliation(s)
- T Lejen
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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Svensson C, Silverstone AE, Lai ZW, Lundberg K. Dioxin-induced adseverin expression in the mouse thymus is strictly regulated and dependent on the aryl hydrocarbon receptor. Biochem Biophys Res Commun 2002; 291:1194-200. [PMID: 11883943 DOI: 10.1006/bbrc.2002.6582] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ligand for the ubiquitous, intracellular aryl hydrocarbon receptor (AhR), up-regulates the actin-modulating protein adseverin in mouse lymphoid tissues, a response that may be correlated to the immunotoxicity of TCDD. Here, by using chimeric mice with TCDD-responsive (AhR(+/+)) hematopoietic cells and TCDD-unresponsive (AhR(minus sign/minus sign)) thymic stroma, or the reverse, we show that TCDD-induced expression of adseverin in thymus is dependent on AhR expression in hematopoietic cells but not in stroma. The use of fetal thymic organ cultures also indicates that TCDD-induced expression of adseverin is confined to the thymocytes. The thymic stroma showed no induction of adseverin expression after TCDD exposure, although TCDD clearly activated the AhR in these cells, as indicated by the induction of CYP1A1. Adseverin was not induced in the thymus of normal adult C57BL/6 mice exposed to beta-estradiol or dexamethasone, two other agents, which also cause thymic atrophy. This further supports that adseverin induction is a specific gene regulatory effect by TCDD on thymocytes.
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Affiliation(s)
- Camilla Svensson
- Department of Pharmaceutical Biosciences, Division of Toxicology, P.O. Box 594, Uppsala University, E-751 24 Uppsala, Sweden.
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