1
|
Nakamura F. The Role of Mechanotransduction in Contact Inhibition of Locomotion and Proliferation. Int J Mol Sci 2024; 25:2135. [PMID: 38396812 PMCID: PMC10889191 DOI: 10.3390/ijms25042135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/30/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
Contact inhibition (CI) represents a crucial tumor-suppressive mechanism responsible for controlling the unbridled growth of cells, thus preventing the formation of cancerous tissues. CI can be further categorized into two distinct yet interrelated components: CI of locomotion (CIL) and CI of proliferation (CIP). These two components of CI have historically been viewed as separate processes, but emerging research suggests that they may be regulated by both distinct and shared pathways. Specifically, recent studies have indicated that both CIP and CIL utilize mechanotransduction pathways, a process that involves cells sensing and responding to mechanical forces. This review article describes the role of mechanotransduction in CI, shedding light on how mechanical forces regulate CIL and CIP. Emphasis is placed on filamin A (FLNA)-mediated mechanotransduction, elucidating how FLNA senses mechanical forces and translates them into crucial biochemical signals that regulate cell locomotion and proliferation. In addition to FLNA, trans-acting factors (TAFs), which are proteins or regulatory RNAs capable of directly or indirectly binding to specific DNA sequences in distant genes to regulate gene expression, emerge as sensitive players in both the mechanotransduction and signaling pathways of CI. This article presents methods for identifying these TAF proteins and profiling the associated changes in chromatin structure, offering valuable insights into CI and other biological functions mediated by mechanotransduction. Finally, it addresses unanswered research questions in these fields and delineates their possible future directions.
Collapse
Affiliation(s)
- Fumihiko Nakamura
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin 300072, China
| |
Collapse
|
2
|
He S, Zhang J, Liu Z, Wang Y, Hao X, Wang X, Zhou Z, Ye X, Zhao Y, Zhao Y, Wang R. Upregulated Cytoskeletal Proteins Promote Pathological Angiogenesis in Moyamoya Disease. Stroke 2023; 54:3153-3164. [PMID: 37886851 DOI: 10.1161/strokeaha.123.044476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 09/26/2023] [Indexed: 10/28/2023]
Abstract
BACKGROUND Moyamoya disease (MMD) is a rare progressive vascular disease that leads to intracranial internal carotid artery stenosis and eventual occlusion. However, its pathogenesis remains unclear. The purpose of this study is to explore the role of abnormally expressed proteins in the pathogenesis of MMD. METHODS Data-independent acquisition mass spectrometry identifies the differentially expressed proteins in MMD serum by detecting the serum from 60 patients with MMD and 20 health controls. The differentially expressed proteins were validated using enzyme linked immunosorbent assays. Immunofluorescence for superficial temporal artery and middle cerebral artery specimens was used to explore the morphological changes of vascular wall in MMD. In vitro experiments were used to explore the changes and mechanisms of differentially expressed proteins on endothelial cells. RESULTS Proteomic analysis showed that a total of 14 726 peptides and 1555 proteins were quantified by mass spectrometry data. FLNA (filamin A) and ZYX (zyxin) proteins were significantly higher in MMD serum compared with those in health controls (Log2FC >2.9 and >2.8, respectively). Immunofluorescence revealed an intimal hyperplasia in superficial temporal artery and middle cerebral artery specimens of MMD. FLNA and ZYX proteins increased the proportion of endothelial cells in S phase and promoted their proliferation, angiogenesis, and cytoskeleton enlargement. Mechanistic studies revealed that AKT (serine/threonine kinase)/GSK-3β (glycogen synthase kinase 3β)/β-catenin signaling pathway plays a major role in these FLNA- and ZYX-induced changes in endothelial cells. CONCLUSIONS This study provides proteomic data on a large sample size of MMD. The differential expression of FLNA and ZYX in patient with MMD and following in vitro experiments suggest that these upregulated proteins are related to the pathology of cerebrovascular intimal hyperplasia in MMD and are involved in MMD pathogenesis, with diagnostic and therapeutic ramifications.
Collapse
Affiliation(s)
- Shihao He
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
- China National Clinical Research Center for Neurological Diseases, Beijing, China (S.H., Yuanli Zhao, R.W.)
- Center of Stroke, Beijing Institute for Brain Disorders, China (S.H., Yuanli Zhao)
| | - Junze Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Ziqi Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Yanru Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Xiaokuan Hao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Xilong Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Zhenyu Zhou
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Xun Ye
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Yahui Zhao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
| | - Yuanli Zhao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
- China National Clinical Research Center for Neurological Diseases, Beijing, China (S.H., Yuanli Zhao, R.W.)
- Center of Stroke, Beijing Institute for Brain Disorders, China (S.H., Yuanli Zhao)
- Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, China (Yuanli Zhao, R.W.)
| | - Rong Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (S.H., J.Z., Z.L., Y.W., X.H., X.W., Z.Z., X.Y., Yahui Zhao, Yuanli Zhao, R.W.)
- China National Clinical Research Center for Neurological Diseases, Beijing, China (S.H., Yuanli Zhao, R.W.)
- Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, China (Yuanli Zhao, R.W.)
| |
Collapse
|
3
|
Zhao X, Kiyozuka K, Konishi A, Kawabata-Iwakawa R, Minamishima YA, Obinata H. Actin-binding protein Filamin B regulates the cell-surface retention of endothelial sphingosine 1-phosphate receptor 1. J Biol Chem 2023:104851. [PMID: 37220855 PMCID: PMC10300261 DOI: 10.1016/j.jbc.2023.104851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/09/2023] [Accepted: 05/11/2023] [Indexed: 05/25/2023] Open
Abstract
Sphingosine 1-phosphate receptor 1 (S1PR1) is a G protein-coupled receptor essential for vascular development and postnatal vascular homeostasis. When exposed to sphingosine 1-phosphate (S1P) in the blood of ∼1 μM, S1PR1 in endothelial cells retains cell-surface localization, while lymphocyte S1PR1 shows almost complete internalization, suggesting the cell-surface retention of S1PR1 is endothelial cell-specific. To identify regulating factors that function to retain S1PR1 on the endothelial cell surface, here we utilized an enzyme-catalyzed proximity labeling technique followed by proteomic analyses. We identified Filamin B (FLNB), an actin-binding protein involved in F-actin cross-linking, as a candidate regulating protein. We show FLNB knockdown by RNA interference induced massive internalization of S1PR1 into early endosomes, which was partially ligand-dependent and required receptor phosphorylation. Further investigation showed FLNB was also important for the recycling of internalized S1PR1 back to the cell surface. FLNB knockdown did not affect the localization of S1PR3, another S1P receptor subtype expressed in endothelial cells, nor did it affect localization of ectopically expressed β2-adrenergic receptor. Functionally, we show FLNB knockdown in endothelial cells impaired S1P-induced intracellular phosphorylation events and directed cell migration and enhancement of the vascular barrier. Taken together, our results demonstrate that FLNB is a novel regulator critical for S1PR1 cell-surface localization and thereby proper endothelial cell function.
Collapse
Affiliation(s)
- Xian Zhao
- Department of Biochemistry, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Keisuke Kiyozuka
- Department of Biochemistry, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Akimitsu Konishi
- Department of Biochemistry, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Reika Kawabata-Iwakawa
- Division of Integrated Oncology Research, Gunma University Initiative for Advanced Research, Gunma University, Gunma, Japan
| | | | - Hideru Obinata
- Education and Research Support Center, Gunma University Graduate School of Medicine, Gunma, Japan.
| |
Collapse
|
4
|
Ma B, Melton E, Wiener R, Zhou N, Wu W, Lai L, Wang C, Costa KD, Qiu H. Age and Blood Pressure Contribute to Aortic Cell and Tissue Stiffness Through Distinct Mechanisms. Hypertension 2022; 79:1777-1788. [PMID: 35766034 PMCID: PMC9308762 DOI: 10.1161/hypertensionaha.121.18950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Aortic stiffening is strongly associated with both aging and hypertension, but the underlying mechanisms remain unclear. We hypothesized that aging-induced aortic stiffness is mediated by a mechanism differing from hypertension. METHODS We conducted comprehensive in vivo and in vitro experiments using multiple rat models to dissect the different mechanisms of aortic stiffening mediated by aging and hypertension. RESULTS A time-course study in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) normotensive rats showed more pronounced aging-associated aortic stiffening in SHR versus WKY. Angiotensin II-induced hypertension was associated with more significant aortic stiffening in older versus young WKY rats. Hypertension aggravated aging effects on aortic wall thickness and extracellular matrix content, indicating combinational effects of aging and hypertension on aortic stiffening. Intrinsic stiffness of isolated aortic vascular smooth muscle cells (VSMCs) increased with age in WKY rats, although no significant difference between older SHR and older WKY VSMCs was observed in 2-dimensional culture, reconstituted 3-dimensional tissues were stiffer for older SHR versus older WKY. A selective inhibitor that reduced hypertension-mediated aortic stiffening did not decrease age-related stiffening in aortic VSMCs and aortic wall. Integrin β1 and SM22 (smooth muscle-specific SM22 protein) expression were negligibly changed in WKY VSMCs during aging but were markedly increased by hypertension in older versus young WKY VSMCs. A notable shift of filamin isoforms from B to A was detected in older WKY VSMCs. CONCLUSIONS Our results indicate distinct mechanisms mediating aging-associated aortic VSMC and vessel stiffness, providing new insights into aortic stiffening and the pathogenesis of hypertension in the elderly.
Collapse
Affiliation(s)
- Ben Ma
- Center for Molecular and Translational Medicine, Institute of Biomedical Sciences, Georgia State University, Atlanta, GA (B.M., E.M., W.W., L.L., H.Q.).,Division of Physiology, Department of Basic Sciences (B.M., N.Z., H.Q.), School of Medicine, Loma Linda University, CA
| | - Elaina Melton
- Center for Molecular and Translational Medicine, Institute of Biomedical Sciences, Georgia State University, Atlanta, GA (B.M., E.M., W.W., L.L., H.Q.)
| | - Robert Wiener
- Department of Medicine (Cardiology), Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York, NY (R.W., K.D.C.)
| | - Ning Zhou
- Division of Physiology, Department of Basic Sciences (B.M., N.Z., H.Q.), School of Medicine, Loma Linda University, CA
| | - Wenqian Wu
- Center for Molecular and Translational Medicine, Institute of Biomedical Sciences, Georgia State University, Atlanta, GA (B.M., E.M., W.W., L.L., H.Q.)
| | - Lo Lai
- Center for Molecular and Translational Medicine, Institute of Biomedical Sciences, Georgia State University, Atlanta, GA (B.M., E.M., W.W., L.L., H.Q.)
| | - Charles Wang
- Department of Basic Sciences & Center for Genomics (C.W.), School of Medicine, Loma Linda University, CA
| | - Kevin D Costa
- Department of Medicine (Cardiology), Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York, NY (R.W., K.D.C.)
| | - Hongyu Qiu
- Center for Molecular and Translational Medicine, Institute of Biomedical Sciences, Georgia State University, Atlanta, GA (B.M., E.M., W.W., L.L., H.Q.).,Division of Physiology, Department of Basic Sciences (B.M., N.Z., H.Q.), School of Medicine, Loma Linda University, CA
| |
Collapse
|
5
|
Chung S, Le TP, Vishwakarma V, Cheng YL, Andrew DJ. Isoform-specific roles of the Drosophila filamin-type protein Jitterbug (Jbug) during development. Genetics 2021; 219:iyab100. [PMID: 34173831 PMCID: PMC8860385 DOI: 10.1093/genetics/iyab100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/20/2021] [Indexed: 11/14/2022] Open
Abstract
Filamins are highly conserved actin-crosslinking proteins that regulate organization of the actin cytoskeleton. As key components of versatile signaling scaffolds, filamins are implicated in developmental anomalies and cancer. Multiple isoforms of filamins exist, raising the possibility of distinct functions for each isoform during development and in disease. Here, we provide an initial characterization of jitterbug (jbug), which encodes one of the two filamin-type proteins in Drosophila. We generate Jbug antiserum that recognizes all of the spliced forms and reveals differential expression of different Jbug isoforms during development, and a significant maternal contribution of Jbug protein. To reveal the function of Jbug isoforms, we create new genetic tools, including a null allele that deletes all isoforms, hypomorphic alleles that affect only a subset, and UAS lines for Gal4-driven expression of the major isoforms. Using these tools, we demonstrate that Jbug is required for viability and that specific isoforms are required in the formation of actin-rich protrusions including thoracic bristles in adults and ventral denticles in the embryo. We also show that specific isoforms of Jbug show differential localization within epithelia and that maternal and zygotic loss of jbug disrupts Crumbs (Crb) localization in several epithelial cell types.
Collapse
Affiliation(s)
- SeYeon Chung
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Thao Phuong Le
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Vishakha Vishwakarma
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Yim Ling Cheng
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Deborah J Andrew
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| |
Collapse
|
6
|
Agarwal R, Paulo JA, Toepfer CN, Ewoldt JK, Sundaram S, Chopra A, Zhang Q, Gorham J, DePalma SR, Chen CS, Gygi SP, Seidman CE, Seidman JG. Filamin C Cardiomyopathy Variants Cause Protein and Lysosome Accumulation. Circ Res 2021; 129:751-766. [PMID: 34405687 PMCID: PMC9053646 DOI: 10.1161/circresaha.120.317076] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Radhika Agarwal
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Joao A. Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Christopher N. Toepfer
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Radcliffe Department of Medicine, University of Oxford, OX3 9DU, UK
- Wellcome Centre for Human Genetics, University of Oxford, OX3 7BN, UK
| | - Jourdan K. Ewoldt
- Department of Biomedical Engineering, Boston University, Boston, MA 02115, USA
| | - Subramanian Sundaram
- Department of Biomedical Engineering, Boston University, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Anant Chopra
- Department of Biomedical Engineering, Boston University, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Qi Zhang
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Joshua Gorham
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Steven R. DePalma
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Christopher S. Chen
- Department of Biomedical Engineering, Boston University, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Steven P. Gygi
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Christine E. Seidman
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - J. G. Seidman
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Corresponding Author: Jonathan G Seidman, , 77 Avenue Louis Pasteur, Boston, MA 02115
| |
Collapse
|
7
|
Conte G, Piciacchia F, Medeiros-Domingo A, Grego S, Ripellino P, Auricchio A. Filamin C missense variant associated with severe right atrial disease and skeletal myopathy. J Cardiovasc Electrophysiol 2021; 32:2777-2780. [PMID: 34411373 DOI: 10.1111/jce.15218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/28/2021] [Accepted: 08/11/2021] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Filamin C (FLNC) gene variants associated with atrial cardiomyopathies have not been reported so far. The aim of this study was to assess the genetics of two siblings presenting with recurrent right atrial arrhythmias, severe right atrial dilatation, and skeletal myopathy. METHODS A family with subjects affected by recurrent atrial arrhythmias and skeletal myopathy was extensively evaluated by the means of electrocardiographic recordings, magnetic resonance, intracardiac high-density mapping, and genetic testing. RESULTS Two siblings with right atrial arrhythmias and severe right atrial disease were found to be heterozygous carriers of the variant FLNC-c.925G>A p.(Glu309Lys), previously reported as a variant of uncertain significance. Despite the presence of a severe dilatation of the right atrium in both patients, one presented with skeletal muscle myopathy and an atrial arrhythmia refractory to pharmacological and invasive treatment, while the other one did not have any myopathy, and rhythm control was easily achieved by drugs. CONCLUSION Filamin C missense variant c.925G>A p.(Glu309Lys) is associated with the severe right atrial disease. Considering cosegregation with the disease (PP1 supporting), this variant should be classified as likely pathogenic.
Collapse
Affiliation(s)
- Giulio Conte
- Istituto Cardiocentro Ticino, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Flavia Piciacchia
- Istituto Cardiocentro Ticino, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | | | - Susanna Grego
- Istituto Cardiocentro Ticino, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Paolo Ripellino
- Neurocentro, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Angelo Auricchio
- Istituto Cardiocentro Ticino, Ente Ospedaliero Cantonale, Lugano, Switzerland
| |
Collapse
|
8
|
Goodman CA, Davey JR, Hagg A, Parker BL, Gregorevic P. Dynamic Changes to the Skeletal Muscle Proteome and Ubiquitinome Induced by the E3 Ligase, ASB2β. Mol Cell Proteomics 2021; 20:100050. [PMID: 33516941 PMCID: PMC8042406 DOI: 10.1016/j.mcpro.2021.100050] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 02/06/2023] Open
Abstract
Ubiquitination is a posttranslational protein modification that has been shown to have a range of effects, including regulation of protein function, interaction, localization, and degradation. We have previously shown that the muscle-specific ubiquitin E3 ligase, ASB2β, is downregulated in models of muscle growth and that overexpression ASB2β is sufficient to induce muscle atrophy. To gain insight into the effects of increased ASB2β expression on skeletal muscle mass and function, we used liquid chromatography coupled to tandem mass spectrometry to investigate ASB2β-mediated changes to the skeletal muscle proteome and ubiquitinome, via a parallel analysis of remnant diGly-modified peptides. The results show that viral vector-mediated ASB2β overexpression in murine muscles causes progressive muscle atrophy and impairment of force-producing capacity, while ASB2β knockdown induces mild muscle hypertrophy. ASB2β-induced muscle atrophy and dysfunction were associated with the early downregulation of mitochondrial and contractile protein abundance and the upregulation of proteins involved in proteasome-mediated protein degradation (including other E3 ligases), protein synthesis, and the cytoskeleton/sarcomere. The overexpression ASB2β also resulted in marked changes in protein ubiquitination; however, there was no simple relationship between changes in ubiquitination status and protein abundance. To investigate proteins that interact with ASB2β and, therefore, potential ASB2β targets, Flag-tagged wild-type ASB2β, and a mutant ASB2β lacking the C-terminal SOCS box domain (dSOCS) were immunoprecipitated from C2C12 myotubes and subjected to label-free proteomic analysis to determine the ASB2β interactome. ASB2β was found to interact with a range of cytoskeletal and nuclear proteins. When combined with the in vivo ubiquitinomic data, our studies have identified novel putative ASB2β target substrates that warrant further investigation. These findings provide novel insight into the complexity of proteome and ubiquitinome changes that occur during E3 ligase-mediated skeletal muscle atrophy and dysfunction.
Collapse
Affiliation(s)
- Craig A Goodman
- Department of Physiology, Centre for Muscle Research (CMR), The University of Melbourne, Victoria, Australia; Australian Institute for Musculoskeletal Science (AIMSS), Sunshine Hospital, The University of Melbourne, St Albans, Victoria, Australia
| | - Jonathan R Davey
- Department of Physiology, Centre for Muscle Research (CMR), The University of Melbourne, Victoria, Australia; Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Adam Hagg
- Department of Physiology, Centre for Muscle Research (CMR), The University of Melbourne, Victoria, Australia; Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia; Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Benjamin L Parker
- Department of Physiology, Centre for Muscle Research (CMR), The University of Melbourne, Victoria, Australia; Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, NSW, Australia.
| | - Paul Gregorevic
- Department of Physiology, Centre for Muscle Research (CMR), The University of Melbourne, Victoria, Australia; Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia; Department of Neurology, The University of Washington School of Medicine, Seattle, Washington, USA.
| |
Collapse
|
9
|
Lamsoul I, Dupré L, Lutz PG. Molecular Tuning of Filamin A Activities in the Context of Adhesion and Migration. Front Cell Dev Biol 2020; 8:591323. [PMID: 33330471 PMCID: PMC7714767 DOI: 10.3389/fcell.2020.591323] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 11/05/2020] [Indexed: 01/08/2023] Open
Abstract
The dynamic organization of actin cytoskeleton meshworks relies on multiple actin-binding proteins endowed with distinct actin-remodeling activities. Filamin A is a large multi-domain scaffolding protein that cross-links actin filaments with orthogonal orientation in response to various stimuli. As such it plays key roles in the modulation of cell shape, cell motility, and differentiation throughout development and adult life. The essentiality and complexity of Filamin A is highlighted by mutations that lead to a variety of severe human disorders affecting multiple organs. One of the most conserved activity of Filamin A is to bridge the actin cytoskeleton to integrins, thereby maintaining the later in an inactive state. We here review the numerous mechanisms cells have developed to adjust Filamin A content and activity and focus on the function of Filamin A as a gatekeeper to integrin activation and associated adhesion and motility.
Collapse
Affiliation(s)
- Isabelle Lamsoul
- Centre de Physiopathologie de Toulouse Purpan, INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| | - Loïc Dupré
- Centre de Physiopathologie de Toulouse Purpan, INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Pierre G Lutz
- Centre de Physiopathologie de Toulouse Purpan, INSERM, CNRS, Université de Toulouse, UPS, Toulouse, France
| |
Collapse
|
10
|
Welter H, Herrmann C, Fröhlich T, Flenkenthaler F, Eubler K, Schorle H, Nettersheim D, Mayerhofer A, Müller-Taubenberger A. Filamin A Orchestrates Cytoskeletal Structure, Cell Migration and Stem Cell Characteristics in Human Seminoma TCam-2 Cells. Cells 2020; 9:E2563. [PMID: 33266100 PMCID: PMC7761120 DOI: 10.3390/cells9122563] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/19/2020] [Accepted: 11/26/2020] [Indexed: 12/16/2022] Open
Abstract
Filamins are large dimeric F-actin cross-linking proteins, crucial for the mechanosensitive properties of a number of cell types. Due to their interaction with a variety of different proteins, they exert important regulatory functions. However, in the human testis the role of filamins has been insufficiently explored. Immunohistochemical staining of human testis samples identified filamin A (FLNA) in spermatogonia and peritubular myoid cells. Investigation of different testicular tumor samples indicated that seminoma also express FLNA. Moreover, mass spectrometric analyses identified FLNA as one of the most abundant proteins in human seminoma TCam-2 cells. We therefore focused on FLNA in TCam-2 cells, and identified by co-immunoprecipitation LAD1, RUVBL1 and DAZAP1, in addition to several cytoskeletal proteins, as interactors of FLNA. To study the role of FLNA in TCam-2 cells, we generated FLNA-deficient cells using the CRISPR/Cas9 system. Loss of FLNA causes an irregular arrangement of the actin cytoskeleton and mechanical instability, impaired adhesive properties and disturbed migratory behavior. Furthermore, transcriptional activity of typical stem cell factors is increased in the absence of FLNA. In summary, our data suggest that FLNA is crucially involved in balancing stem cell characteristics and invasive properties in human seminoma cells and possibly human testicular germ cells.
Collapse
Affiliation(s)
- Harald Welter
- Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany; (H.W.); (C.H.); (K.E.); (A.M.-T.)
| | - Carola Herrmann
- Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany; (H.W.); (C.H.); (K.E.); (A.M.-T.)
| | - Thomas Fröhlich
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig Maximilian University of Munich, 81377 Munich, Germany; (T.F.); (F.F.)
| | - Florian Flenkenthaler
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig Maximilian University of Munich, 81377 Munich, Germany; (T.F.); (F.F.)
| | - Katja Eubler
- Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany; (H.W.); (C.H.); (K.E.); (A.M.-T.)
| | - Hubert Schorle
- Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany;
| | - Daniel Nettersheim
- Department of Urology, Urological Research Lab, Translational UroOncology, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Artur Mayerhofer
- Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany; (H.W.); (C.H.); (K.E.); (A.M.-T.)
| | - Annette Müller-Taubenberger
- Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany; (H.W.); (C.H.); (K.E.); (A.M.-T.)
| |
Collapse
|
11
|
Abstract
Cancer progression is dependent on heightened mechanical adaptation, both for the cells' ability to change shape and to interact with varying mechanical environments. This type of adaptation is dependent on mechanoresponsive proteins that sense and respond to mechanical stress, as well as their regulators. Mechanoresponsive proteins are part of the mechanobiome, which is the larger network that constitutes the cell's mechanical systems that are also highly integrated with many other cellular systems, such as gene expression, metabolism, and signaling. Despite the altered expression patterns of key mechanobiome proteins across many different cancer types, pharmaceutical targeting of these proteins has been overlooked. Here, we review the biochemistry of key mechanoresponsive proteins, specifically nonmuscle myosin II, α-actinins, and filamins, as well as the partnering proteins 14-3-3 and CLP36. We also examined a wide range of data sets to assess how gene and protein expression levels of these proteins are altered across many different cancer types. Finally, we determined the potential of targeting these proteins to mitigate invasion or metastasis and suggest that the mechanobiome is a goldmine of opportunity for anticancer drug discovery and development.
Collapse
Affiliation(s)
- Eleana Parajón
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Alexandra Surcel
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Douglas N Robinson
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Chemical and Biomolecular Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland
| |
Collapse
|
12
|
Kelley CA, Triplett O, Mallick S, Burkewitz K, Mair WB, Cram EJ. FLN-1/ filamin is required to anchor the actomyosin cytoskeleton and for global organization of sub-cellular organelles in a contractile tissue. Cytoskeleton (Hoboken) 2020; 77:379-398. [PMID: 32969593 DOI: 10.1002/cm.21633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/11/2020] [Accepted: 09/17/2020] [Indexed: 01/01/2023]
Abstract
Actomyosin networks are organized in space, direction, size, and connectivity to produce coordinated contractions across cells. We use the C. elegans spermatheca, a tube composed of contractile myoepithelial cells, to study how actomyosin structures are organized. FLN-1/filamin is required for the formation and stabilization of a regular array of parallel, contractile, actomyosin fibers in this tissue. Loss of fln-1 results in the detachment of actin fibers from the basal surface, which then accumulate along the cell junctions and are stabilized by spectrin. In addition, actin and myosin are captured at the nucleus by the linker of nucleoskeleton and cytoskeleton complex (LINC) complex, where they form large foci. Nuclear positioning and morphology, distribution of the endoplasmic reticulum and the mitochondrial network are also disrupted. These results demonstrate that filamin is required to prevent large actin bundle formation and detachment, to prevent excess nuclear localization of actin and myosin, and to ensure correct positioning of organelles.
Collapse
Affiliation(s)
- Charlotte A Kelley
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Olivia Triplett
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Samyukta Mallick
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Kristopher Burkewitz
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, Massachusetts, USA.,Department of Cell and Developmental Biology, Vanderbilt School of Medicine, Nashville, Tennessee, USA
| | - William B Mair
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Erin J Cram
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| |
Collapse
|
13
|
Vähätupa M, Järvinen TAH, Uusitalo-Järvinen H. Exploration of Oxygen-Induced Retinopathy Model to Discover New Therapeutic Drug Targets in Retinopathies. Front Pharmacol 2020; 11:873. [PMID: 32595503 PMCID: PMC7300227 DOI: 10.3389/fphar.2020.00873] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 05/27/2020] [Indexed: 12/11/2022] Open
Abstract
Oxygen-induced retinopathy (OIR) is a pure hypoxia-driven angiogenesis model and the most widely used model for ischemic retinopathies, such as retinopathy of prematurity (ROP), proliferative diabetic retinopathy (PDR), and retinal vein occlusion (RVO). OIR model has been used to test new potential anti-angiogenic factors for human diseases. We have recently performed the most comprehensive characterization of OIR by a relatively novel mass spectrometry (MS) technique, sequential window acquisition of all theoretical fragment ion mass spectra (SWATH-MS) proteomics and used genetically modified mice strains to identify novel molecular drug targets in angiogenic retinal diseases. We have confirmed the relevance of the identified molecular targets to human diseases by determining their expression pattern in neovascular membranes obtained from PDR and RVO patients. Based on our results, crystallins were the most prominent proteins induced by early hypoxic environment during the OIR, while actomyosin complex and Filamin A-R-Ras axis, that regulates vascular permeability of the angiogenic blood vessels, stood out at the peak of angiogenesis. Our results have revealed potential new therapeutic targets to address hypoxia-induced pathological angiogenesis and the associated vascular permeability in number of retinal diseases.
Collapse
Affiliation(s)
- Maria Vähätupa
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Tero A. H. Järvinen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Department of Orthopedics and Traumatology, Tampere University Hospital, Tampere, Finland
| | - Hannele Uusitalo-Järvinen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Eye Centre, Tampere University Hospital, Tampere, Finland
| |
Collapse
|
14
|
Avila-Bonilla RG, Yocupicio-Monroy M, Marchat LA, Pérez-Ishiwara DG, Cerecedo-Mercado DA, Del Ángel RM, Salas-Benito JS. miR-927 has pro-viral effects during acute and persistent infection with dengue virus type 2 in C6/36 mosquito cells. J Gen Virol 2020; 101:825-839. [PMID: 32478656 DOI: 10.1099/jgv.0.001441] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dengue virus (DENV) is an important flavivirus that is transmitted to humans by Aedes mosquitoes, where it can establish a persistent infection underlying vertical and horizontal transmission. However, the exact mechanism of persistent DENV infection is not well understood. Recently miR-927 was found to be upregulated in C6/36-HT cells at 57 weeks of persistent infection (C6-L57), suggesting its participation during this type of infection. The aim of this study was to determine the role of miR-927 during infection with DENV type 2. The results indicate an overexpression of miR-927 in C6-L57 cells and acutely infected cells according to the time of infection and the m.o.i. used. The downregulation of miR-927 in C6-L57 cells results in a reduction of both viral titre and viral genome copy number. The overexpression of miR-927 in C6-L40 and C6/36 cells infected at an m.o.i. of 0.1 causes an increase in both viral titre and viral genome copy number, suggesting a pro-viral activity of miR-927. In silico prediction analysis reveals target mRNAs for miR-927 are implicated in post-translational modifications (SUMO), translation factors (eIF-2B), the innate immune system (NKIRAS), exocytosis (EXOC-2), endocytosis (APM1) and the cytoskeleton (FLN). The expression levels of FLN were the most affected by both miR-927 overexpression and inhibition, and FLN was determined to be a direct target of miR-927 by a dual-luciferase gene reporter assay. FLN has been associated with the regulation of the Toll pathway and either overexpression or downregulation of miR-927 resulted in expression changes of antimicrobial peptides (Cecropins A and G, and Defensin D) involved in the Toll pathway response.
Collapse
Affiliation(s)
- Rodolfo Gamaliel Avila-Bonilla
- Programa de Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico
| | - Martha Yocupicio-Monroy
- Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México, San Lorenzo 290, Del Valle, Mexico City CP 03100, Mexico
| | - Laurence A Marchat
- Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico.,Programa de Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico
| | - David Guillermo Pérez-Ishiwara
- Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico.,Programa de Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico
| | - Doris Atenea Cerecedo-Mercado
- Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico.,Programa de Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico
| | - Rosa María Del Ángel
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Avenida Instituto Politécnico Nacional 2508, San Pedro Zacatenco, Mexico City CP 07360, Mexico
| | - Juan Santiago Salas-Benito
- Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico.,Programa de Doctorado en Ciencias en Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera 249, La Escalera-Ticomán, Mexico City CP 07320, Mexico
| |
Collapse
|
15
|
Tokuraku K, Kuragano M, Uyeda TQP. Long-Range and Directional Allostery of Actin Filaments Plays Important Roles in Various Cellular Activities. Int J Mol Sci 2020; 21:E3209. [PMID: 32370032 DOI: 10.3390/ijms21093209] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/27/2020] [Accepted: 04/30/2020] [Indexed: 12/18/2022] Open
Abstract
A wide variety of uniquely localized actin-binding proteins (ABPs) are involved in various cellular activities, such as cytokinesis, migration, adhesion, morphogenesis, and intracellular transport. In a micrometer-scale space such as the inside of cells, protein molecules diffuse throughout the cell interior within seconds. In this condition, how can ABPs selectively bind to particular actin filaments when there is an abundance of actin filaments in the cytoplasm? In recent years, several ABPs have been reported to induce cooperative conformational changes to actin filaments allowing structural changes to propagate along the filament cables uni- or bidirectionally, thereby regulating the subsequent binding of ABPs. Such propagation of ABP-induced cooperative conformational changes in actin filaments may be advantageous for the elaborate regulation of cellular activities driven by actin-based machineries in the intracellular space, which is dominated by diffusion. In this review, we focus on long-range allosteric regulation driven by cooperative conformational changes of actin filaments that are evoked by binding of ABPs, and discuss roles of allostery of actin filaments in narrow intracellular spaces.
Collapse
|
16
|
Peng F, Zhou Y, Wang J, Guo B, Wei Y, Deng H, Wu Z, Zhang C, Shi K, Li Y, Wang X, Shore P, Zhao S, Deng W. The transcription factor Sp1 modulates RNA polymerase III gene transcription by controlling BRF1 and GTF3C2 expression in human cells. J Biol Chem 2020; 295:4617-4630. [PMID: 32115405 DOI: 10.1074/jbc.ra119.011555] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/16/2020] [Indexed: 01/10/2023] Open
Abstract
Specificity protein 1 (Sp1) is an important transcription factor implicated in numerous cellular processes. However, whether Sp1 is involved in the regulation of RNA polymerase III (Pol III)-directed gene transcription in human cells remains unknown. Here, we first show that filamin A (FLNA) represses Sp1 expression as well as expression of TFIIB-related factor 1 (BRF1) and general transcription factor III C subunit 2 (GTF3C2) in HeLa, 293T, and SaOS2 cell lines stably expressing FLNA-silencing shRNAs. Both BRF1 promoter 4 (BRF1P4) and GTF3C2 promoter 2 (GTF3C2P2) contain putative Sp1-binding sites, suggesting that Sp1 affects Pol III gene transcription by regulating BRF1 and GTF3C2 expression. We demonstrate that Sp1 knockdown inhibits Pol III gene transcription, BRF1 and GTF3C2 expression, and the proliferation of 293T and HeLa cells, whereas Sp1 overexpression enhances these activities. We obtained a comparable result in a cell line in which both FLNA and Sp1 were depleted. These results indicate that Sp1 is involved in the regulation of Pol III gene transcription independently of FLNA expression. Reporter gene assays showed that alteration of Sp1 expression affects BRF1P4 and GTF3C2P2 activation, suggesting that Sp1 modulates Pol III-mediated gene transcription by controlling BRF1 and GTF3C2 gene expression. Further analysis revealed that Sp1 interacts with and thereby promotes the occupancies of TATA box-binding protein, TFIIAα, and p300 at both BRF1P4 and GTF3C2P2. These findings indicate that Sp1 controls Pol III-directed transcription and shed light on how Sp1 regulates cancer cell proliferation.
Collapse
Affiliation(s)
- Feixia Peng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Ying Zhou
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Juan Wang
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Baoqiang Guo
- Centre for Bioscience, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester M1 5GD, United Kingdom
| | - Yun Wei
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Huan Deng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Zihui Wu
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Cheng Zhang
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Kaituo Shi
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Yuan Li
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Xin Wang
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Paul Shore
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Shasha Zhao
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| | - Wensheng Deng
- College of Life Science and Health, Wuhan University of Science and Technology, Wuhan 430065, China
| |
Collapse
|
17
|
Verdonschot JAJ, Vanhoutte EK, Claes GRF, Helderman-van den Enden ATJM, Hoeijmakers JGJ, Hellebrekers DMEI, de Haan A, Christiaans I, Lekanne Deprez RH, Boen HM, van Craenenbroeck EM, Loeys BL, Hoedemaekers YM, Marcelis C, Kempers M, Brusse E, van Waning JI, Baas AF, Dooijes D, Asselbergs FW, Barge-Schaapveld DQCM, Koopman P, van den Wijngaard A, Heymans SRB, Krapels IPC, Brunner HG. A mutation update for the FLNC gene in myopathies and cardiomyopathies. Hum Mutat 2020; 41:1091-1111. [PMID: 32112656 PMCID: PMC7318287 DOI: 10.1002/humu.24004] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/12/2020] [Accepted: 02/25/2020] [Indexed: 12/11/2022]
Abstract
Filamin C (FLNC) variants are associated with cardiac and muscular phenotypes. Originally, FLNC variants were described in myofibrillar myopathy (MFM) patients. Later, high‐throughput screening in cardiomyopathy cohorts determined a prominent role for FLNC in isolated hypertrophic and dilated cardiomyopathies (HCM and DCM). FLNC variants are now among the more prevalent causes of genetic DCM. FLNC‐associated DCM is associated with a malignant clinical course and a high risk of sudden cardiac death. The clinical spectrum of FLNC suggests different pathomechanisms related to variant types and their location in the gene. The appropriate functioning of FLNC is crucial for structural integrity and cell signaling of the sarcomere. The secondary protein structure of FLNC is critical to ensure this function. Truncating variants with subsequent haploinsufficiency are associated with DCM and cardiac arrhythmias. Interference with the dimerization and folding of the protein leads to aggregate formation detrimental for muscle function, as found in HCM and MFM. Variants associated with HCM are predominantly missense variants, which cluster in the ROD2 domain. This domain is important for binding to the sarcomere and to ensure appropriate cell signaling. We here review FLNC genotype–phenotype correlations based on available evidence.
Collapse
Affiliation(s)
- Job A J Verdonschot
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Cardiology, Cardiovascular Research Institute (CARIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Els K Vanhoutte
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Godelieve R F Claes
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | | | | | - Debby M E I Hellebrekers
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Amber de Haan
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Imke Christiaans
- Department of Clinical Genetics, Amsterdam University Medical Center, Amsterdam, The Netherlands.,Department of Clinical Genetics, University Medical Centre Groningen, Groningen, The Netherlands
| | - Ronald H Lekanne Deprez
- Department of Clinical Genetics, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Hanne M Boen
- Department of Cardiology, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | | | - Bart L Loeys
- Department of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Yvonne M Hoedemaekers
- Department of Clinical Genetics, University Medical Centre Groningen, Groningen, The Netherlands.,Department of Clinical Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Carlo Marcelis
- Department of Clinical Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Marlies Kempers
- Department of Clinical Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Esther Brusse
- Department of Neurology, Erasmus MC University Medical Centre, Rotterdam, The Netherlands
| | - Jaap I van Waning
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands.,Department of Cardiology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Annette F Baas
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dennis Dooijes
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Folkert W Asselbergs
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | | | - Arthur van den Wijngaard
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Stephane R B Heymans
- Department of Cardiology, Cardiovascular Research Institute (CARIM), Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Cardiovascular Sciences, Centre for Molecular and Vascular Biology, KU Leuven, Leuven, Belgium.,The Netherlands Heart Institute, Utrecht, The Netherlands
| | - Ingrid P C Krapels
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Han G Brunner
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Clinical Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Genetics and Cell Biology, GROW Institute for Developmental Biology and Cancer, Maastricht University Medical Centre, Maastricht, The Netherlands
| |
Collapse
|
18
|
Guo RH, Im YJ, Shin SI, Jeong K, Rhee JH, Kim YR. Vibrio vulnificus RtxA1 cytotoxin targets filamin A to regulate PAK1- and MAPK-dependent cytoskeleton reorganization and cell death. Emerg Microbes Infect 2019; 8:934-945. [PMID: 31237474 PMCID: PMC6598492 DOI: 10.1080/22221751.2019.1632153] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cytoskeletal rearrangement and acute cytotoxicity occur in Vibrio vulnificus-infected host cells. RtxA1 toxin, a multifunctional autoprocessing repeats-in-toxin (MARTX), is essential for the pathogenesis of V. vulnificus and the programmed necrotic cell death. In this study, HeLa cells expressing RtxA1 amino acids 1491–1971 fused to GFP were observed to be rounded. Through yeast two-hybrid screening and subsequent immunoprecipitation validation assays, we confirmed the specific binding of a RtxA11491–1971 fragment with host-cell filamin A, an actin cross-linking scaffold protein. Downregulation of filamin A expression decreased the cytotoxicity of RtxA1 toward host cells. Furthermore, the phosphorylation of JNK and p38 MAPKs was induced by the RtxA1-filamin A interaction during the toxin-mediated cell death. However, the phosphorylation of these MAPKs was not observed during the RtxA1 intoxication of filamin A-deficient M2 cells. In addition, the depletion of pak1, which appeared to be activated by the RtxA1-filamin A interaction, inhibited RtxA1-induced phosphorylation of JNK and p38, and the cells treated with a pak1 inhibitor exhibited decreased RtxA1-mediated cytoskeletal rearrangement and cytotoxicity. Thus, the binding of filamin A by the RtxA11491–1971 domain appears to be a requisite to pak1-mediated MAPK activation, which contributes to the cytoskeletal reorganization and host cell death.
Collapse
Affiliation(s)
- Rui Hong Guo
- a College of Pharmacy and Research Institute of Drug Development , Chonnam National University , Gwangju , Republic of Korea
| | - Young Jun Im
- a College of Pharmacy and Research Institute of Drug Development , Chonnam National University , Gwangju , Republic of Korea
| | - Soo Im Shin
- c Department of Bioengineering and Biotechnology, College of Engineering , Chonnam National University , Gwangju , Republic of Korea
| | - Kwangjoon Jeong
- b Clinical Vaccine R&D Center and Department of Microbiology , Chonnam National University Medical School , Hwasun , Republic of Korea
| | - Joon Haeng Rhee
- b Clinical Vaccine R&D Center and Department of Microbiology , Chonnam National University Medical School , Hwasun , Republic of Korea
| | - Young Ran Kim
- a College of Pharmacy and Research Institute of Drug Development , Chonnam National University , Gwangju , Republic of Korea
| |
Collapse
|
19
|
Abstract
Global changes in the state of spatially distributed systems can often be traced back to perturbations that arise locally. Whether such local perturbations grow into global changes depends on the system geometry and the spatial spreading of these perturbations. Here, we investigate how different spreading behaviors of local perturbations determine their global impact in 1-dimensional systems of different size. Specifically, we assessed sliding arrest events in in vitro motility assays where myosins propel actin, and simulated the underlying mechanochemistry of myosins that bind along the actin filament. We observed spontaneous sliding arrest events that occurred more frequently for shorter actin filaments. This observation could be explained by spontaneous local arrest of myosin kinetics that stabilizes once it spreads throughout an entire actin filament. When we introduced intermediate concentrations of the actin cross-linker filamin, longer actin was arrested more frequently. This observation was reproduced by simulations where filamin binding induces persistent local arrest of myosin kinetics, which subsequently spreads throughout the actin filament. A spin chain model with nearest-neighbor coupling reproduced key features of our experiments and simulations, thus extending to other linear systems with nearest-neighbor coupling the following conclusions: 1) perturbations that are persistent only once they spread throughout the system are more effective in smaller systems, and 2) perturbations that are persistent upon their establishment are more effective in larger systems. Beyond these general conclusions, our work also provides a theoretical model of collective myosin kinetics with a finite range of mechanical coupling along the actin filament.
Collapse
|
20
|
Toomer K, Sauls K, Fulmer D, Guo L, Moore K, Glover J, Stairley R, Bischoff J, Levine RA, Norris RA. Filamin-A as a Balance between Erk/Smad Activities During Cardiac Valve Development. Anat Rec (Hoboken) 2018; 302:117-124. [PMID: 30288957 PMCID: PMC6312478 DOI: 10.1002/ar.23911] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/30/2018] [Accepted: 02/21/2018] [Indexed: 11/10/2022]
Abstract
Mitral valve prolapse (MVP) affects 2.4% of the population and has poorly understood etiology. Recent genetic studies have begun to unravel the complexities of MVP and through these efforts, mutations in the FLNA (Filamin-A) gene were identified as disease causing. Our in vivo and in vitro studies have validated these genetic findings and have revealed FLNA as a central regulator of valve morphogenesis. The mechanisms by which FLNA mutations result in myxomatous mitral valve disease are currently unknown, but may involve proteins previously associated with mutated regions of the FLNA protein, such as the small GTPase signaling protein, R-Ras. Herein, we report that Filamin-A is required for R-Ras expression and activation of the Ras-Mek-Erk pathway. Loss of the Ras/Erk pathway correlated with hyperactivation of pSmad2/3, increased extracellular matrix (ECM) production and enlarged mitral valves. Analyses of integrin receptors in the mitral valve revealed that Filamin-A was required for β1-integrin expression and provided a potential mechanism for impaired ECM compaction and valve enlargement. Our data support Filamin-A as a protein that regulates the balance between Erk and Smad activation and an inability of Filamin-A deficient valve interstitial cells to effectively remodel the increased ECM production through a β1-integrin mechanism. As a consequence, loss of Filamin-A function results in increased ECM production and generation of a myxomatous phenotype characterized by improperly compacted mitral valve tissue. Anat Rec, 302:117-124, 2019. © 2018 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Katelynn Toomer
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Kimberly Sauls
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Diana Fulmer
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Lilong Guo
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Kelsey Moore
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Janiece Glover
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Rebecca Stairley
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Joyce Bischoff
- Vascular Biology Program and Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Robert A Levine
- Cardiac Ultrasound Laboratory, Cardiology Division, Massachusetts General Hospital Research Institute, Harvard Medical School, Boston, Massachusetts
| | - Russell A Norris
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| |
Collapse
|
21
|
Jahan F, Madhavan S, Rolova T, Viazmina L, Grönholm M, Gahmberg CG. Phosphorylation of the α-chain in the integrin LFA-1 enables β2-chain phosphorylation and α-actinin binding required for cell adhesion. J Biol Chem 2018; 293:12318-12330. [PMID: 29903913 DOI: 10.1074/jbc.ra118.004318] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 06/11/2018] [Indexed: 11/06/2022] Open
Abstract
The integrin leukocyte function-associated antigen-1 (LFA-1) plays a pivotal role in leukocyte adhesion and migration, but the mechanism(s) by which this integrin is regulated has remained incompletely understood. LFA-1 integrin activity requires phosphorylation of its β2-chain and interactions of its cytoplasmic tail with various cellular proteins. The α-chain is constitutively phosphorylated and necessary for cellular adhesion, but how the α-chain regulates adhesion has remained enigmatic. We now show that substitution of the α-chain phosphorylation site (S1140A) in T cells inhibits the phosphorylation of the functionally important Thr-758 in the β2-chain, binding of α-actinin and 14-3-3 protein, and expression of an integrin-activating epitope after treatment with the stromal cell-derived factor-1α. The presence of this substitution resulted in a loss of cell adhesion and directional cell migration. Moreover, LFA-1 activation through the T-cell receptor in cells expressing the S1140A LFA-1 variant resulted in less Thr-758 phosphorylation, α-actinin and talin binding, and cell adhesion. The finding that the LFA-1 α-chain regulates adhesion through the β-chain via specific phosphorylation at Ser-1140 in the α-chain has not been previously reported and emphasizes that both chains are involved in the regulation of LFA-1 integrin activity.
Collapse
Affiliation(s)
- Farhana Jahan
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| | - Sudarrshan Madhavan
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| | - Taisia Rolova
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| | - Larisa Viazmina
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| | - Mikaela Grönholm
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| | - Carl G Gahmberg
- From the Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Program, University of Helsinki, Helsinki 00014 UH, Finland
| |
Collapse
|
22
|
Green HJ, Griffiths AG, Ylänne J, Brown NH. Novel functions for integrin-associated proteins revealed by analysis of myofibril attachment in Drosophila. eLife 2018; 7:35783. [PMID: 30028294 PMCID: PMC6092120 DOI: 10.7554/elife.35783] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 07/19/2018] [Indexed: 01/18/2023] Open
Abstract
We use the myotendinous junction of Drosophila flight muscles to explore why many integrin associated proteins (IAPs) are needed and how their function is coordinated. These muscles revealed new functions for IAPs not required for viability: Focal Adhesion Kinase (FAK), RSU1, tensin and vinculin. Genetic interactions demonstrated a balance between positive and negative activities, with vinculin and tensin positively regulating adhesion, while FAK inhibits elevation of integrin activity by tensin, and RSU1 keeps PINCH activity in check. The molecular composition of myofibril termini resolves into 4 distinct layers, one of which is built by a mechanotransduction cascade: vinculin facilitates mechanical opening of filamin, which works with the Arp2/3 activator WASH to build an actin-rich layer positioned between integrins and the first sarcomere. Thus, integration of IAP activity is needed to build the complex architecture of the myotendinous junction, linking the membrane anchor to the sarcomere. Our body consists of many different types of cells that build our tissues and organs. To do so, cells need to be able to stick together. One family of proteins called integrins helps to keep cells connected. They sit across cell membranes and anchor cells to the networks of protein fibres outside cells that link and strengthen our organs, and also connect muscles to tendons. In fruit flies, the indirect flight muscle attach to the thorax of the insect, and create wing movements by ‘deforming’ the thorax. These flight muscles resemble the muscles of animals with a backbone, and consist of many different fibres. At the end of these fibres is a plaque of a protein important for muscle contraction, known as actin. Integrins attach to these actin plaques, allowing the ends of the muscle to anchor to the tendon. Integrins form complexes with so-called 'integrin-associated proteins' inside the cell, which regulate integrin. Integrins and integrin-associated proteins are essential for proper muscle development, but until now it was not fully understood how they interact with each other. Here, Green et al. explored the role of some of these proteins in the indirect flight muscles of fruit flies. This revealed that the connection between muscle and tendon is a balancing act. Some integrin associated proteins boost the attachment, whilst others block it. One protein, tensin, increased integrin attachment, whilst another, FAK, blocked tensin, decreasing attachment. Similarly, a protein called PINCH expands the attachment, whilst a protein called RSU1 reduced the activity of PINCH to the correct level. Moreover, the end point of the muscle fibres was discovered to be composed of four distinct layers, including a newly identified layer of actin, which is built by three other integrin-associated proteins. The flight muscles of fruit flies are similar in structure to the skeletal muscles that move our own limbs. An important next step is to discover whether these integrin-associated proteins work similarly in our muscles. A better understanding of how they work together could help with research into diseases of the muscles.
Collapse
Affiliation(s)
- Hannah J Green
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.,Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.,Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Annabel Gm Griffiths
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Jari Ylänne
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.,Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Nicholas H Brown
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
23
|
Berrou E, Adam F, Lebret M, Planche V, Fergelot P, Issertial O, Coupry I, Bordet JC, Nurden P, Bonneau D, Colin E, Goizet C, Rosa JP, Bryckaert M. Gain-of-Function Mutation in Filamin A Potentiates Platelet Integrin α IIbβ 3 Activation. Arterioscler Thromb Vasc Biol 2017; 37:1087-1097. [PMID: 28428218 DOI: 10.1161/atvbaha.117.309337] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 03/31/2017] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Dominant mutations of the X-linked filamin A (FLNA) gene are responsible for filaminopathies A, which are rare disorders including brain periventricular nodular heterotopia, congenital intestinal pseudo-obstruction, cardiac valves or skeleton malformations, and often macrothrombocytopenia. APPROACH AND RESULTS We studied a male patient with periventricular nodular heterotopia and congenital intestinal pseudo-obstruction, his unique X-linked FLNA allele carrying a stop codon mutation resulting in a 100-amino acid-long FLNa C-terminal extension (NP_001447.2: p.Ter2648SerextTer101). Platelet counts were normal, with few enlarged platelets. FLNa was detectable in all platelets but at 30% of control levels. Surprisingly, all platelet functions were significantly upregulated, including platelet aggregation and secretion, as induced by ADP, collagen, or von Willebrand factor in the presence of ristocetin, as well as thrombus formation in blood flow on a collagen or on a von Willebrand factor matrix. Most importantly, patient platelets stimulated with ADP exhibited a marked increase in αIIbβ3 integrin activation and a parallel increase in talin recruitment to β3, contrasting with normal Rap1 activation. These results are consistent with the mutant FLNa affecting the last step of αIIbβ3 activation. Overexpression of mutant FLNa in the HEL megakaryocytic cell line correlated with an increase (compared with wild-type FLNa) in PMA-induced fibrinogen binding to and in talin and kindlin-3 recruitment by αIIbβ3. CONCLUSIONS Altogether, our results are consistent with a less binding of mutant FLNa to β3 and the facilitated recruitment of talin by β3 on platelet stimulation, explaining the increased αIIbβ3 activation and the ensuing gain-of-platelet functions.
Collapse
Affiliation(s)
- Eliane Berrou
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Frédéric Adam
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Marilyne Lebret
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Virginie Planche
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Patricia Fergelot
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Odile Issertial
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Isabelle Coupry
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Jean-Claude Bordet
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Paquita Nurden
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Dominique Bonneau
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Estelle Colin
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Cyril Goizet
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Jean-Philippe Rosa
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.)
| | - Marijke Bryckaert
- From the INSERM UMR_S 1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin Bicêtre, France (E.B., F.A., M.L., V.P., O.I., J.-P.R., M.B.); INSERM UMR_S 1211, Université de Bordeaux, CHU Bordeaux UNIV EA 4576, Place Aurélie Raba-Léon, France (P.F., I.C., C.G.); CHU Bordeaux, Centre de Référence Anomalies du Développement Embryonnaire, Service de Génétique Médicale, Hôpital Pellegrin, Place Aurélie Raba-Léon, France (P.F., C.G.); Unité d'Hémostase Biologique, Hospices Civils de Lyon, CBE Bron, EA4609 and CIQLE-Lyon Bio Image, Université Lyon, France (J.-C.B.); Institut Hospitalo-Universitaire LIRYC PTIB, Hôpital Xavier Arnozan, av du Haut Lévêque, Pessac, France (P.N.); and Département de Biochimie et Génétique, INSERM UMR_S 1083 - CNRS 6214, CHU Angers, Angers, France (D.B., E.C.).
| |
Collapse
|
24
|
Ithychanda SS, Dou K, Robertson SP, Qin J. Structural and thermodynamic basis of a frontometaphyseal dysplasia mutation in filamin A. J Biol Chem 2017; 292:8390-8400. [PMID: 28348077 DOI: 10.1074/jbc.m117.776740] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/10/2017] [Indexed: 01/12/2023] Open
Abstract
Filamin-mediated linkages between transmembrane receptors (TR) and the actin cytoskeleton are crucial for regulating many cytoskeleton-dependent cellular processes such as cell shape change and migration. A major TR binding site in the immunoglobulin repeat 21 (Ig21) of filamin is masked by the adjacent repeat Ig20, resulting in autoinhibition. The TR binding to this site triggers the relief of Ig20 and protein kinase A (PKA)-mediated phosphorylation of Ser-2152, thereby dynamically regulating the TR-actin linkages. A P2204L mutation in Ig20 reportedly cause frontometaphyseal dysplasia, a skeletal disorder with unknown pathogenesis. We show here that the P2204L mutation impairs a hydrophobic core of Ig20, generating a conformationally fluctuating molten globule-like state. Consequently, unlike in WT filamin, where PKA-mediated Ser-2152 phosphorylation is ligand-dependent, the P2204L mutant is readily accessible to PKA, promoting ligand-independent phosphorylation on Ser-2152. Strong TR peptide ligands from platelet GP1bα and G-protein-coupled receptor MAS effectively bound Ig21 by displacing Ig20 from autoinhibited WT filamin, but surprisingly, the capacity of these ligands to bind the P2204L mutant was much reduced despite the mutation-induced destabilization of the Ig20 structure that supposedly weakens the autoinhibition. Thermodynamic analysis indicated that compared with WT filamin, the conformationally fluctuating state of the Ig20 mutant makes Ig21 enthalpically favorable to bind ligand but with substantial entropic penalty, resulting in total higher free energy and reduced ligand affinity. Overall, our results reveal an unusual structural and thermodynamic basis for the P2204L-induced dysfunction of filamin and frontometaphyseal dysplasia disease.
Collapse
Affiliation(s)
- Sujay S Ithychanda
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Kevin Dou
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | | | - Jun Qin
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195.
| |
Collapse
|
25
|
Lee G, Schwarz TL. Filamin, a synaptic organizer in Drosophila, determines glutamate receptor composition and membrane growth. eLife 2016; 5. [PMID: 27914199 PMCID: PMC5173320 DOI: 10.7554/elife.19991] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 11/23/2016] [Indexed: 11/27/2022] Open
Abstract
Filamin is a scaffolding protein that functions in many cells as an actin-crosslinker. FLN90, an isoform of the Drosophila ortholog Filamin/cheerio that lacks the actin-binding domain, is here shown to govern the growth of postsynaptic membrane folds and the composition of glutamate receptor clusters at the larval neuromuscular junction. Genetic and biochemical analyses revealed that FLN90 is present surrounding synaptic boutons. FLN90 is required in the muscle for localization of the kinase dPak and, downstream of dPak, for localization of the GTPase Ral and the exocyst complex to this region. Consequently, Filamin is needed for growth of the subsynaptic reticulum. In addition, in the absence of filamin, type-A glutamate receptor subunits are lacking at the postsynapse, while type-B subunits cluster correctly. Receptor composition is dependent on dPak, but independent of the Ral pathway. Thus two major aspects of synapse formation, morphological plasticity and subtype-specific receptor clustering, require postsynaptic Filamin. DOI:http://dx.doi.org/10.7554/eLife.19991.001
Collapse
Affiliation(s)
- GaYoung Lee
- The F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States
| | - Thomas L Schwarz
- The F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States
| |
Collapse
|
26
|
Wang J, Zhao S, Wei Y, Zhou Y, Shore P, Deng W. Cytoskeletal Filamin A Differentially Modulates RNA Polymerase III Gene Transcription in Transformed Cell Lines. J Biol Chem 2016; 291:25239-25246. [PMID: 27738102 DOI: 10.1074/jbc.m116.735886] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 10/11/2016] [Indexed: 11/06/2022] Open
Abstract
Cytoskeletal filamin A (FLNA) is an important protein involved in multiple cellular processes. Previous studies have shown that FLNA can promote or inhibit cancer growth and development; however, the mechanisms underlying these events are not fully understood. Here we show that, in both 293T and SaOS2 cells, knockdown of FLNA significantly enhanced transcription of RNA polymerase (pol) III-transcribed genes except for a subset of tRNA genes. In contrast, re-expression of FLNA in an FLNA-deficient melanoma cell line (A7) repressed transcription of all pol III-transcribed genes, suggesting that FLNA inhibits pol III transcription in a cell type-specific manner. Chromatin immunoprecipitation assays revealed that the repression of pol III gene transcription by FLNA correlates with the decreased occupancy of the RNA pol III transcription machinery at promoters. Immunofluorescence microscopy and coimmunoprecipitation assays revealed that FLNA can associate with the RNA pol III transcription machinery through its actin-binding domain within nuclei. Mechanistic analysis revealed that FLNA suppresses pol III gene transcription by confining the recruitment of the RNA pol III transcription machinery at the promoters of the genes that are sensitive to the alteration of FLNA expression. These findings not only extend the understanding of FLNA function in cells but also provide novel insights into the mechanism by which FLNA represses cell proliferation.
Collapse
Affiliation(s)
- Juan Wang
- From the Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan, Hubei Province 430065, China and
| | - Shasha Zhao
- From the Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan, Hubei Province 430065, China and
| | - Yun Wei
- From the Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan, Hubei Province 430065, China and
| | - Ying Zhou
- From the Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan, Hubei Province 430065, China and
| | - Paul Shore
- the Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Wensheng Deng
- From the Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan, Hubei Province 430065, China and
| |
Collapse
|
27
|
Houlihan SL, Lanctot AA, Guo Y, Feng Y. Upregulation of neurovascular communication through filamin abrogation promotes ectopic periventricular neurogenesis. eLife 2016; 5. [PMID: 27664421 PMCID: PMC5050022 DOI: 10.7554/elife.17823] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 09/23/2016] [Indexed: 02/02/2023] Open
Abstract
Neuronal fate-restricted intermediate progenitors (IPs) are derived from the multipotent radial glia (RGs) and serve as the direct precursors for cerebral cortical neurons, but factors that control their neurogenic plasticity remain elusive. Here we report that IPs’ neuron production is enhanced by abrogating filamin function, leading to the generation of periventricular neurons independent of normal neocortical neurogenesis and neuronal migration. Loss of Flna in neural progenitor cells (NPCs) led RGs to undergo changes resembling epithelial-mesenchymal transition (EMT) along with exuberant angiogenesis that together changed the microenvironment and increased neurogenesis of IPs. We show that by collaborating with β-arrestin, Flna maintains the homeostatic signaling between the vasculature and NPCs, and loss of this function results in escalated Vegfa and Igf2 signaling, which exacerbates both EMT and angiogenesis to further potentiate IPs’ neurogenesis. These results suggest that the neurogenic potential of IPs may be boosted in vivo by manipulating Flna-mediated neurovascular communication. DOI:http://dx.doi.org/10.7554/eLife.17823.001
Collapse
Affiliation(s)
- Shauna L Houlihan
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, United States.,Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, United States.,Driskill Graduate Program, Northwestern University Feinberg School of Medicine, Chicago, United States
| | - Alison A Lanctot
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, United States.,Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, United States.,Driskill Graduate Program, Northwestern University Feinberg School of Medicine, Chicago, United States
| | - Yan Guo
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, United States.,Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, United States
| | - Yuanyi Feng
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, United States.,Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, United States
| |
Collapse
|
28
|
Jiang Y, Sverdlov MS, Toth PT, Huang LS, Du G, Liu Y, Natarajan V, Minshall RD. Phosphatidic Acid Produced by RalA-activated PLD2 Stimulates Caveolae-mediated Endocytosis and Trafficking in Endothelial Cells. J Biol Chem 2016; 291:20729-38. [PMID: 27510034 DOI: 10.1074/jbc.m116.752485] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Indexed: 11/06/2022] Open
Abstract
Caveolae are the primary route for internalization and transendothelial transport of macromolecules, such as insulin and albumin. Caveolae-mediated endocytosis is activated by Src-dependent caveolin-1 (Cav-1) phosphorylation and subsequent recruitment of dynamin-2 and filamin A (FilA), which facilitate vesicle fission and trafficking, respectively. Here, we tested the role of RalA and phospholipase D (PLD) signaling in the regulation of caveolae-mediated endocytosis and trafficking. The addition of albumin to human lung microvascular endothelial cells induced the activation of RalA within minutes, and siRNA-mediated down-regulation of RalA abolished fluorescent BSA uptake. Co-immunoprecipitation studies revealed that albumin induced the association between RalA, Cav-1, and FilA; however, RalA knockdown with siRNA did not affect FilA recruitment to Cav-1, suggesting that RalA was not required for FilA and Cav-1 complex formation. Rather, RalA probably facilitates caveolae-mediated endocytosis by activating downstream effectors. PLD2 was shown to be activated by RalA, and inhibition of PLD2 abolished Alexa-488-BSA uptake, indicating that phosphatidic acid (PA) generated by PLD2 may facilitate caveolae-mediated endocytosis. Furthermore, using a PA biosensor, GFP-PASS, we observed that BSA induced an increase in PA co-localization with Cav-1-RFP, which could be blocked by a dominant negative PLD2 mutant. Total internal reflection fluorescence microscopy studies of Cav-1-RFP also showed that fusion of caveolae with the basal plasma membrane was dependent on PLD2 activity. Thus, our results suggest that the small GTPase RalA plays an important role in promoting invagination and trafficking of caveolae, not by potentiating the association between Cav-1 and FilA but by stimulating PLD2-mediated generation of phosphatidic acid.
Collapse
Affiliation(s)
- Ying Jiang
- From the School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China, the Departments of Anesthesiology
| | | | | | - Long Shuang Huang
- Pharmacology, and Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612, and
| | - Guangwei Du
- the Departments of Integrative Biology and Pharmacology, University of Texas Health Science Center, Houston, Texas 77030
| | - Yiyao Liu
- From the School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
| | - Viswanathan Natarajan
- Pharmacology, and Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612, and
| | | |
Collapse
|
29
|
Dotson D, Woodruff EA, Villalta F, Dong X. Filamin A Is Involved in HIV-1 Vpu-mediated Evasion of Host Restriction by Modulating Tetherin Expression. J Biol Chem 2016; 291:4236-46. [PMID: 26742839 DOI: 10.1074/jbc.m115.708123] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Indexed: 11/06/2022] Open
Abstract
Tetherin, also known as bone marrow stromal antigen 2 (BST-2), inhibits the release of a wide range of enveloped viruses, including human immunodeficiency virus, type 1 (HIV-1) by directly tethering nascent virions to the surface of infected cells. The HIV-1 accessary protein Vpu counteracts tetherin restriction via sequestration, down-regulation, and/or displacement mechanisms to remove tetherin from sites of virus budding. However, the exact mechanism of Vpu-mediated antagonism of tetherin restriction remains to be fully understood. Here we report a novel role for the actin cross-linking regulator filamin A (FLNa) in Vpu anti-tetherin activities. We demonstrate that FLNa associates with tetherin and that FLNa modulates tetherin turnover. FLNa deficiency was found to enhance cell surface and steady-state levels of tetherin expression. In contrast, we observed that overexpression of FLNa reduced tetherin expression levels both on the plasma membrane and in intracellular compartments. Although FLNb shows high amino acid sequence similarity with FLNa, we reveal that only FLNa, but not FLNb, plays an essential role in tetherin turnover. We further showed that FLNa deficiency inhibited Vpu-mediated enhancement of virus release through interfering with the activity of Vpu to down-regulate cellular tetherin. Taken together, our studies suggest that Vpu hijacks the FLNa function in the modulation of tetherin to neutralize the antiviral factor tetherin. These findings may provide novel strategies for the treatment of HIV-1 infection.
Collapse
Affiliation(s)
- Dominique Dotson
- From the Department of Microbiology and Immunology and Center for AIDS Health Disparities Research, School of Medicine, Meharry Medical College, Nashville, Tennessee 37208
| | - Elvin A Woodruff
- From the Department of Microbiology and Immunology and Center for AIDS Health Disparities Research, School of Medicine, Meharry Medical College, Nashville, Tennessee 37208
| | - Fernando Villalta
- From the Department of Microbiology and Immunology and Center for AIDS Health Disparities Research, School of Medicine, Meharry Medical College, Nashville, Tennessee 37208
| | - Xinhong Dong
- From the Department of Microbiology and Immunology and Center for AIDS Health Disparities Research, School of Medicine, Meharry Medical College, Nashville, Tennessee 37208
| |
Collapse
|
30
|
Abstract
Microtubule dynamics are important for axon growth during development as well as axon regeneration after injury. We have previously identified HDAC5 as an injury-regulated tubulin deacetylase that functions at the injury site to promote axon regeneration. However, the mechanisms involved in the spatial control of HDAC5 activity remain poorly understood. Here we reveal that HDAC5 interacts with the actin binding protein filamin A via its C-terminal domain. Filamin A plays critical roles in HDAC5-dependent tubulin deacetylation because, in cells lacking filamin A, the levels of acetylated tubulin are elevated markedly. We found that nerve injury increases filamin A axonal expression in a protein synthesis-dependent manner. Reducing filamin A levels or interfering with the interaction between HDAC5 and filamin A prevents injury-induced tubulin deacetylation as well as HDAC5 localization at the injured axon tips. In addition, neurons lacking filamin A display reduced axon regeneration. Our findings suggest a model in which filamin A local translation following axon injury controls localized HDAC5 activity to promote axon regeneration.
Collapse
Affiliation(s)
- Yongcheol Cho
- From the Department of Anatomy and Neurobiology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri 63110 and
| | - Dongeun Park
- the School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea
| | - Valeria Cavalli
- From the Department of Anatomy and Neurobiology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri 63110 and
| |
Collapse
|
31
|
Alli AA, Bao HF, Liu BC, Yu L, Aldrugh S, Montgomery DS, Ma HP, Eaton DC. Calmodulin and CaMKII modulate ENaC activity by regulating the association of MARCKS and the cytoskeleton with the apical membrane. Am J Physiol Renal Physiol 2015; 309:F456-63. [PMID: 26136560 DOI: 10.1152/ajprenal.00631.2014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 06/24/2015] [Indexed: 11/22/2022] Open
Abstract
Phosphatidylinositol bisphosphate (PIP2) regulates epithelial sodium channel (ENaC) open probability. In turn, myristoylated alanine-rich C kinase substrate (MARCKS) protein or MARCKS-like protein 1 (MLP-1) at the plasma membrane regulates the delivery of PIP2 to ENaC. MARCKS and MLP-1 are regulated by changes in cytosolic calcium; increasing calcium promotes dissociation of MARCKS from the membrane, but the calcium-regulatory mechanisms are unclear. However, it is known that increased intracellular calcium can activate calmodulin and we show that inhibition of calmodulin with calmidazolium increases ENaC activity presumably by regulating MARCKS and MLP-1. Activated calmodulin can regulate MARCKS and MLP-1 in two ways. Calmodulin can bind to the effector domain of MARCKS or MLP-1, inactivating both proteins by causing their dissociation from the membrane. Mutations in MARCKS that prevent calmodulin association prevent dissociation of MARCKS from the membrane. Calmodulin also activates CaM kinase II (CaMKII). An inhibitor of CaMKII (KN93) increases ENaC activity, MARCKS association with ENaC, and promotes MARCKS movement to a membrane fraction. CaMKII phosphorylates filamin. Filamin is an essential component of the cytoskeleton and promotes association of ENaC, MARCKS, and MLP-1. Disruption of the cytoskeleton with cytochalasin E reduces ENaC activity. CaMKII phosphorylation of filamin disrupts the cytoskeleton and the association of MARCKS, MLP-1, and ENaC, thereby reducing ENaC open probability. Taken together, these findings suggest calmodulin and CaMKII modulate ENaC activity by destabilizing the association between the actin cytoskeleton, ENaC, and MARCKS, or MLP-1 at the apical membrane.
Collapse
Affiliation(s)
- Abdel A Alli
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Hui-Fang Bao
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Bing-Chen Liu
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Ling Yu
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Summer Aldrugh
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Darrice S Montgomery
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - He-Ping Ma
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| | - Douglas C Eaton
- Center for Cell and Molecular Signaling, Department of Physiology, Emory University School of Medicine; Atlanta, Georgia
| |
Collapse
|
32
|
Becker B, Doan JM, Wustman B, Carpenter EJ, Chen L, Zhang Y, Wong GKS, Melkonian M. The Origin and Evolution of the Plant Cell Surface: Algal Integrin-Associated Proteins and a New Family of Integrin-Like Cytoskeleton-ECM Linker Proteins. Genome Biol Evol 2015; 7:1580-9. [PMID: 25977459 PMCID: PMC4494055 DOI: 10.1093/gbe/evv089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The extracellular matrix of scaly green flagellates consists of small organic scales consisting of polysaccharides and scale-associated proteins (SAPs). Molecular phylogenies have shown that these organisms represent the ancestral stock of flagellates from which all green plants (Viridiplantae) evolved. The molecular characterization of four different SAPs is presented. Three SAPs are type-2 membrane proteins with an arginine/alanine-rich short cytoplasmic tail and an extracellular domain that is most likely of bacterial origin. The fourth protein is a filamin-like protein. In addition, we report the presence of proteins similar to the integrin-associated proteins α-actinin (in transcriptomes of glaucophytes and some viridiplants), LIM-domain proteins, and integrin-associated kinase in transcriptomes of viridiplants, glaucophytes, and rhodophytes. We propose that the membrane proteins identified are the predicted linkers between scales and the cytoskeleton. These proteins are present in many green algae but are apparently absent from embryophytes. These proteins represent a new protein family we have termed gralins for green algal integrins. Gralins are absent from embryophytes. A model for the evolution of the cell surface proteins in Plantae is discussed.
Collapse
Affiliation(s)
- Burkhard Becker
- Biozentrum Köln, Botanical Institute, Universität zu Köln, Germany
| | - Jean Michel Doan
- Biozentrum Köln, Botanical Institute, Universität zu Köln, Germany
| | - Brandon Wustman
- Biozentrum Köln, Botanical Institute, Universität zu Köln, Germany
| | - Eric J Carpenter
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Li Chen
- BGI-Shenzhen, Bei Shan Industrial Zone, Shenzhen, China
| | - Yong Zhang
- BGI-Shenzhen, Bei Shan Industrial Zone, Shenzhen, China
| | - Gane K-S Wong
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada BGI-Shenzhen, Bei Shan Industrial Zone, Shenzhen, China Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | | |
Collapse
|
33
|
Lian G, Sheen VL. Cytoskeletal proteins in cortical development and disease: actin associated proteins in periventricular heterotopia. Front Cell Neurosci 2015; 9:99. [PMID: 25883548 PMCID: PMC4381626 DOI: 10.3389/fncel.2015.00099] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 03/07/2015] [Indexed: 01/28/2023] Open
Abstract
The actin cytoskeleton regulates many important cellular processes in the brain, including cell division and proliferation, migration, and cytokinesis and differentiation. These developmental processes can be regulated through actin dependent vesicle and organelle movement, cell signaling, and the establishment and maintenance of cell junctions and cell shape. Many of these processes are mediated by extensive and intimate interactions of actin with cellular membranes and proteins. Disruption in the actin cytoskeleton in the brain gives rise to periventricular heterotopia (PH), a malformation of cortical development, characterized by abnormal neurons clustered deep in the brain along the lateral ventricles. This disorder can give rise to seizures, dyslexia and psychiatric disturbances. Anatomically, PH is characterized by a smaller brain (impaired proliferation), heterotopia (impaired initial migration) and disruption along the neuroependymal lining (impaired cell-cell adhesion). Genes causal for PH have also been implicated in actin-dependent processes. The current review provides mechanistic insight into actin cytoskeletal regulation of cortical development in the context of this malformation of cortical development.
Collapse
Affiliation(s)
- Gewei Lian
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School Boston, MA, USA
| | - Volney L Sheen
- Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School Boston, MA, USA
| |
Collapse
|
34
|
Sheen VL. Filamin A mediated Big2 dependent endocytosis: From apical abscission to periventricular heterotopia. Tissue Barriers 2014; 2:e29431. [PMID: 25097827 PMCID: PMC4117685 DOI: 10.4161/tisb.29431] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 05/29/2014] [Accepted: 06/02/2014] [Indexed: 01/23/2023] Open
Abstract
Periventricular heterotopia (PH) is one of the most common malformations of cortical development (MCD). Nodules along the lateral ventricles of the brain, disruption of the ventricular lining, and a reduced brain size are hallmarks of this disorder. PH results in a disruption of the neuroependyma, inhibition of neural proliferation and differentiation, and altered neuronal migration. Human mutations in the genes encoding the actin-binding Filamin A (FLNA) and the vesicle trafficking Brefeldin A-associated guanine exchange factor 2 (BIG2 is encoded by the ARFGEF2 gene) proteins are implicated in PH formation. Recent studies have shown that the transition from proliferating neural progenitors to post-mitotic neurons relies on apical abscission along the neuroepithelium. This mechanism involves an actin dependent contraction of the apical portion of a neural progenitor along the ventricular lining to complete abscission. Actin also maintains stability of various cell adhesion molecules along the neuroependyma. Loss of cadherin directs disassembly of the primary cilium, which transduces sonic-hedgehog (Shh) signaling. Shh signaling is required for continued proliferation. In this context, apical abscission regulates neuronal progenitor exit and migration from the ventricular zone by detachment from the neuroependyma, relies on adhesion molecules that maintain the integrity of the neuroepithelial lining, and directs neural proliferation. Each of these processes is disrupted in PH, suggesting that genes causal for this MCD, may fundamentally mediate apical abscission in cortical development. Here we discuss several recent reports that demonstrate a coordinated role for actin and vesicle trafficking in modulating neural development along the neurepithelium, and potentially the neural stem cell to neuronal transition.
Collapse
Affiliation(s)
- Volney L Sheen
- Department of Neurology; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston, MA USA
| |
Collapse
|
35
|
Abstract
Nuclear positioning is an important process during development and homeostasis. Depending on the affected tissue, mislocalized nuclei can alter cellular processes such as polarization, differentiation, or migration and lead ultimately to diseases. Many cells actively control the position of their nucleus using their cytoskeleton and motor proteins. We have recently shown that during Drosophila oogenesis, nurse cells employ cytoplasmic actin cables in association with perinuclear actin to position their nucleus. Here, we briefly summarize our work and discuss why nuclear positioning in nurse cells is specialized but the molecular mechanisms are likely to be more generally used.
Collapse
Affiliation(s)
- Sven Huelsmann
- The Gurdon Institute and Department of Physiology, Development, and Neuroscience; University of Cambridge; Cambridge, UK; Department of Biological and Environmental Science; University of Jyväskylä; Jyväskylä, Finland
| | - Nicholas H Brown
- The Gurdon Institute and Department of Physiology, Development, and Neuroscience; University of Cambridge; Cambridge, UK
| |
Collapse
|
36
|
Abstract
Neural proliferation, migration and differentiation require reorganization of the actin cytoskeleton and regulation of vesicle trafficking to provide stability in maintaining cell adhesions, allow for changes in cell shape, and establishing cell polarity. Human disorders involving the actin-binding Filamin A (FLNA) and vesicle trafficking Brefeldin-associated guanine exchange factor 2 (BIG2 is encoded by the ARFGEF2 gene) proteins are implicated in these various developmental processes, resulting in a malformation of cortical development called periventricular heterotopia (nodules along the ventricular lining) and microcephaly (small brain). Here we discuss several recent reports from our laboratory that demonstrate a shared role for both proteins in actin-associated vesicle trafficking, which is required to maintain the expression and stability of cell adhesion and cell cycle associated molecules during cortical development. While changes in FLNA and BIG2 have first been linked to disorders involving the central nervous system, increasing reports suggest they are associated with aberrant development of various other organ systems in the body. These studies suggest that vesicle trafficking defects in FLN-GEF dependent pathways may contribute to a much broader phenotype than previously realized.
Collapse
Affiliation(s)
- Volney L Sheen
- Department of Neurology; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston, MA USA
| |
Collapse
|
37
|
Girisha KM, Abdollahpour H, Shah H, Bhavani GS, Graham JM, Boggula VR, Phadke SR, Kutsche K. A syndrome of facial dysmorphism, cubital pterygium, short distal phalanges, swan neck deformity of fingers, and scoliosis. Am J Med Genet A 2014; 164A:1035-40. [PMID: 24458843 DOI: 10.1002/ajmg.a.36381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 11/01/2013] [Indexed: 12/17/2022]
Abstract
We report on an adolescent girl with sparse scalp hair, wide columella extending below alae nasi, webbing at elbows, broad finger tips, short distal phalanx of fingers, swan neck deformity of fingers, scoliosis, tall vertebrae, short fibulae, short fourth metatarsal bone, abnormal distal humeri, and unilateral clubfoot at birth. The combination of these features represents a novel phenotype. We sequenced the protein-coding regions of the FLNA and FLNB genes and did not observe any pathogenic sequence variation. Chromosomal microarray revealed a de novo copy number variation of uncertain clinical significance on 7p22.3.
Collapse
Affiliation(s)
- Katta M Girisha
- Division of Medical Genetics, Department of Pediatrics, Kasturba Medical College, Manipal University, Manipal, India
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Aalberts JJJ, van Tintelen JP, Oomen T, Bergman JEH, Halley DJJ, Jongbloed JDH, Suurmeijer AJH, van den Berg MP. Screening of TGFBR1, TGFBR2, and FLNA in familial mitral valve prolapse. Am J Med Genet A 2013; 164A:113-9. [PMID: 24243761 DOI: 10.1002/ajmg.a.36211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 07/28/2013] [Indexed: 01/19/2023]
Abstract
So far only mutations in the filamin A gene (FLNA) have been identified as causing familial mitral valve prolapse (MVP). Previous studies have linked dysregulation of the transforming growth factor beta (TGF-β) cytokine family to MVP. We investigated whether mutations in the TGF-β receptors genes type I (TGFBR1) and II (TGFBR2) underlie isolated familial MVP cases. Eight families with isolated familial MVP were evaluated clinically and genetically. Ventricular arrhythmias were present in five of the eight families and sudden cardiac death occurred in six patients. Tissue obtained during mitral valve surgery or autopsy was available for histological examination in six cases; all demonstrated myxomatous degeneration. A previously described FLNA missense mutation (p.G288R) was identified in one large family, but no mutations were discovered in TGFBR1 or TGFBR2. An FLNA missense mutation was identified in one family but we found no TGFBR1 or TGFBR2 mutations. Our results suggest that TGFBR1 and TGFBR2 mutations do not play a major role in isolated myxomatous valve dystrophy. Screening for FLNA mutations is recommended in familial myxomatous valvular dystrophy, particularly if X-linked inheritance is suspected.
Collapse
Affiliation(s)
- Jan J J Aalberts
- Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Zakaria R, Lamsoul I, Uttenweiler-Joseph S, Erard M, Monsarrat B, Burlet-Schiltz O, Moog-Lutz C, Lutz PG. Phosphorylation of serine 323 of ASB2α is pivotal for the targeting of filamin A to degradation. Cell Signal 2013; 25:2823-30. [PMID: 24044920 DOI: 10.1016/j.cellsig.2013.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 09/06/2013] [Indexed: 10/26/2022]
Abstract
ASB proteins are the specificity subunits of cullin5-RING E3 ubiquitin ligases (CRL5) that play roles in ubiquitin-mediated protein degradation. However, how their activity is regulated remains poorly understood. Here, we unravel a novel mechanism of regulation of a CRL5 through phosphorylation of its specificity subunit ASB2α. Indeed, using mass spectrometry, we showed for the first time that ASB2α is phosphorylated and that phosphorylation of serine-323 (Ser-323) of ASB2α is crucial for the targeting of the actin-binding protein filamin A (FLNa) to degradation. Mutation of ASB2α Ser-323 to Ala had no effect on intrinsic E3 ubiquitin ligase activity of ASB2α but abolished the ability of ASB2α to induce degradation of FLNa. In contrast, the ASB2α Ser-323 to Asp phosphomimetic mutant induced acute degradation of FLNa. Moreover, inhibition of the extracellular signal-regulated kinases 1 and 2 (Erk1/2) activity reduced ASB2α-mediated FLNa degradation. We further showed that the subcellular localization of ASB2α to actin-rich structures is dependent on ASB2α Ser-323 phosphorylation and propose that the interaction with FLNa depends on the electrostatic potential redistribution induced by the Ser-323 phosphate group. Taken together, these data unravel an important mechanism by which ASB2α-mediated FLNa degradation can be regulated.
Collapse
Affiliation(s)
- Rim Zakaria
- CNRS; IPBS (Institut de Pharmacologie et de Biologie Structurale), 205 route de Narbonne BP 64182, F-31077 Toulouse, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Kovacevic I, Cram EJ. Filamin and Phospholipase C-ε are required for calcium signaling in the Caenorhabditis elegans Spermatheca. Worm 2013; 2:e25717. [PMID: 24778940 PMCID: PMC3875652 DOI: 10.4161/worm.25717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 07/10/2013] [Indexed: 11/23/2022]
Abstract
Mechanical properties of the microenvironment are fundamental in orchestrating normal tissue function, disease progression, and organismal development. Studies of mechanotransduction in cultured cells on artificial substrates have revealed underlying principles, but the in vivo roles of mechanotransduction remain unclear. We recently reported that the Caenorhabditis elegans spermatheca—a myoepithelial tube composed of a cell monolayer—may be mechanosensitive. Live imaging with the genetically encoded calcium indicator GCaMP revealed that oocyte-induced stretching of the spermatheca resulted in calcium oscillations and constriction of the tube. FLN-1/filamin, a mechanosensitive cytoskeletal scaffolding protein, is required to correctly trigger the calcium transients. PLC-1/phospholipase C-epsilon and ITR-1/IP3 receptor are required to produce the calcium transients, and may function downstream of filamin. In addition to providing important insights into the biology of C. elegans, our studies offer a novel and genetically tractable model for studying mechanotransduction in a myoepithelial tissue.
Collapse
Affiliation(s)
- Ismar Kovacevic
- Department of Biology; Northeastern University; Boston, MA USA
| | - Erin J Cram
- Department of Biology; Northeastern University; Boston, MA USA
| |
Collapse
|
41
|
Abstract
BACKGROUND Tissue factor (TF) is the most relevant physiological trigger of thrombosis. Additionally TF is a transmembrane receptor with cell signaling functions. OBJECTIVES The aim of this study was to investigate TF subcellular localization, function and signaling in human coronary artery smooth muscle cell migration. METHODS Coronary arteries and primary cultures of vascular smooth muscle cells (HVSMC) were obtained from human explanted hearts. Wound repair and Boyden chamber assays were used to measure migration in vitro. TF-pro-coagulant activity (TF-PCA) was measured in extracted cellular membranes. Analysis of TF distribution was performed by confocal microscopy. A nucleofector device was used for TF and protease activated receptor 2 (PAR2) silencing. mRNA levels were analyzed by RT-PCR. RESULTS In migrating HVSMC TF translocates to the leading edge of the cells showing an intense patch-like staining in the lamellipodia. In the migrating front TF colocalizes with filamin (FLN) in the polarized lipid rafts. TF-PCA was increased in migrating cells. Silencing of the TF gene inhibits RSK-induced FLN-Ser-2152 phosphorylation, down-regulates CDC42, RhoA, and Rac1 protein expression and significantly inhibits cell migration. Silencing PAR2 also inhibits cell migration; however, silencing both TF and PAR2 induces a significantly higher effect on migration. Smooth muscle cells expressing TF have been identified in non-lipid-rich human coronary artery atherosclerotic plaques. CONCLUSIONS TF translocates to the cell front in association with cytoskeleton proteins and regulates HVSMC migration by mechanisms dependent and independent of factor (F)VIIa/PAR2. These results extend the functional role of TF to smooth muscle cell trafficking in vessel wall remodeling.
Collapse
Affiliation(s)
- E Peña
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Barcelona CIBEROBN-Pathophysiology of Obesity and Nutrition, Barcelona Cardiovascular Research Chair, UAB, Barcelona, Spain
| | | | | |
Collapse
|
42
|
Page RC, Clark JG, Misra S. Structure of filamin A immunoglobulin-like repeat 10 from Homo sapiens. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:871-6. [PMID: 21821884 PMCID: PMC3151117 DOI: 10.1107/s1744309111024249] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 06/20/2011] [Indexed: 11/10/2022]
Abstract
Filamin A (FlnA) plays a critical role in cytoskeletal organization, cell motility and cellular signaling. FlnA utilizes different binding sites on a series of 24 immunoglobulin-like domains (Ig repeats) to interact with diverse cytosolic proteins and with cytoplasmic portions of membrane proteins. Mutations in a specific domain, Ig10 (FlnA-Ig10), are correlated with two severe forms of the otopalatodigital syndrome spectrum disorders Melnick-Needles syndrome and frontometaphyseal dysplasia. The crystal structure of FlnA-Ig10 determined at 2.44 Å resolution provides insight into the perturbations caused by these mutations.
Collapse
Affiliation(s)
- Richard C Page
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
| | | | | |
Collapse
|
43
|
Blagg SL, Battom SE, Annesley SJ, Keller T, Parkinson K, Wu JMF, Fisher PR, Thompson CRL. Cell type-specific filamin complex regulation by a novel class of HECT ubiquitin ligase is required for normal cell motility and patterning. Development 2011; 138:1583-93. [PMID: 21389049 PMCID: PMC3062426 DOI: 10.1242/dev.063800] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2011] [Indexed: 11/20/2022]
Abstract
Differential cell motility, which plays a key role in many developmental processes, is perhaps most evident in examples of pattern formation in which the different cell types arise intermingled before sorting out into discrete tissues. This is thought to require heterogeneities in responsiveness to differentiation-inducing signals that result in the activation of cell type-specific genes and 'salt and pepper' patterning. How differential gene expression results in cell sorting is poorly defined. Here we describe a novel gene (hfnA) that provides the first mechanistic link between cell signalling, differential gene expression and cell type-specific sorting in Dictyostelium. HfnA defines a novel group of evolutionarily conserved HECT ubiquitin ligases with an N-terminal filamin domain (HFNs). HfnA expression is induced by the stalk differentiation-inducing factor DIF-1 and is restricted to a subset of prestalk cells (pstO). hfnA(-) pstO cells differentiate but their sorting out is delayed. Genetic interactions suggest that this is due to misregulation of filamin complex activity. Overexpression of filamin complex members phenocopies the hfnA(-) pstO cell sorting defect, whereas disruption of filamin complex function in a wild-type background results in pstO cells sorting more strongly. Filamin disruption in an hfnA(-) background rescues pstO cell localisation. hfnA(-) cells exhibit altered slug phototaxis phenotypes consistent with filamin complex hyperactivity. We propose that HfnA regulates filamin complex activity and cell type-specific motility through the breakdown of filamin complexes. These findings provide a novel mechanism for filamin regulation and demonstrate that filamin is a crucial mechanistic link between responses to differentiation signals and cell movement in patterning based on 'salt and pepper' differentiation and sorting out.
Collapse
Affiliation(s)
- Simone L. Blagg
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Suzanne E. Battom
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Sarah J. Annesley
- Department of Microbiology, La Trobe University, VIC 3086, Australia
| | - Thomas Keller
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Katie Parkinson
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Jasmine M. F. Wu
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Paul R. Fisher
- Department of Microbiology, La Trobe University, VIC 3086, Australia
| | - Christopher R. L. Thompson
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| |
Collapse
|
44
|
Aguda AH, Sakwe AM, Rask L, Robinson RC. Expression, crystallization and preliminary crystallographic data analysis of filamin A repeats 14-16. Acta Crystallogr Sect F Struct Biol Cryst Commun 2007; 63:291-3. [PMID: 17401197 PMCID: PMC2330200 DOI: 10.1107/s1744309107006689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Accepted: 02/08/2007] [Indexed: 11/10/2022]
Abstract
Human filamin A is a 280 kDa protein involved in actin-filament cross-linking. It is structurally divided into an actin-binding headpiece (ABD) and a rod domain containing 24 immunoglobulin-like (Ig) repeats. A fragment of human filamin A (Ig repeats 14-16) was cloned and expressed in Escherichia coli and the purified protein was crystallized in 1.6 M ammonium sulfate, 2% PEG 1000 and 100 mM HEPES pH 7.5. The crystals diffracted to 1.95 A and belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 50.63, b = 52.10, c = 98.46 A, alpha = beta = gamma = 90 degrees.
Collapse
Affiliation(s)
- Adeleke Halilu Aguda
- Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden.
| | | | | | | |
Collapse
|
45
|
Petrecca K, Miller DM, Shrier A. Localization and enhanced current density of the Kv4.2 potassium channel by interaction with the actin-binding protein filamin. J Neurosci 2000; 20:8736-44. [PMID: 11102480 PMCID: PMC6773047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Kv4.2 potassium channels play a critical role in postsynaptic excitability. Immunocytochemical studies reveal a somatodendritic Kv4.2 expression pattern, with the channels concentrated mainly at dendritic spines. The molecular mechanism that underlies the localization of Kv4.2 to this subcellular region is unknown. We used the yeast two-hybrid system to identify the Kv4.2-associated proteins that are involved in channel localization. Here we demonstrate a direct interaction between Kv4.2 and the actin-binding protein, filamin. We show that Kv4.2 and filamin can be coimmunoprecipitated both in vitro and in brain and that Kv4.2 and filamin share an overlapping expression pattern in the cerebellum and cultured hippocampal neurons. To examine the functional consequences of this interaction, we expressed Kv4.2 in filamin(+) and filamin(-) cells and performed immunocytochemical and electrophysiological analyses. Our results indicate that Kv4.2 colocalizes with filamin at filopodial roots in filamin(+) cells but shows a nonspecific expression pattern in filamin(-) cells, with no localization to filopodial roots. Furthermore, the magnitude of whole-cell Kv4.2 current density is approximately 2.7-fold larger in filamin(+) cells as compared with these currents in filamin(-) cells. We propose that filamin may function as a scaffold protein in the postsynaptic density, mediating a direct link between Kv4.2 and the actin cytoskeleton, and that this interaction is essential for the generation of appropriate Kv4.2 current densities.
Collapse
Affiliation(s)
- K Petrecca
- Department of Physiology, McGill University, Montréal, Québec, Canada H3G 1Y6
| | | | | |
Collapse
|
46
|
van der Ven PF, Wiesner S, Salmikangas P, Auerbach D, Himmel M, Kempa S, Hayess K, Pacholsky D, Taivainen A, Schröder R, Carpén O, Fürst DO. Indications for a novel muscular dystrophy pathway. gamma- filamin, the muscle-specific filamin isoform, interacts with myotilin. J Cell Biol 2000; 151:235-48. [PMID: 11038172 PMCID: PMC2192634 DOI: 10.1083/jcb.151.2.235] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
gamma-Filamin, also called ABP-L, is a filamin isoform that is specifically expressed in striated muscles, where it is predominantly localized in myofibrillar Z-discs. A minor fraction of the protein shows subsarcolemmal localization. Although gamma-filamin has the same overall structure as the two other known isoforms, it is the only isoform that carries a unique insertion in its immunoglobulin (Ig)-like domain 20. Sequencing of the genomic region encoding this part of the molecule shows that this insert is encoded by an extra exon. Transient transfections of the insert-bearing domain in skeletal muscle cells and cardiomyocytes show that this single domain is sufficient for targeting to developing and mature Z-discs. The yeast two-hybrid method was used to identify possible binding partners for the insert-bearing Ig-like domain 20 of gamma-filamin. The two Ig-like domains of the recently described alpha-actinin-binding Z-disc protein myotilin were found to interact directly with this filamin domain, indicating that the amino-terminal end of gamma-filamin may be indirectly anchored to alpha-actinin in the Z-disc via myotilin. Since defects in the myotilin gene were recently reported to cause a form of autosomal dominant limb-girdle muscular dystrophy, our findings provide a further contribution to the molecular understanding of this disease.
Collapse
Affiliation(s)
- P F van der Ven
- Department of Cell Biology, University of Potsdam, D-14471 Potsdam, Germany.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Li MG, Serr M, Edwards K, Ludmann S, Yamamoto D, Tilney LG, Field CM, Hays TS. Filamin is required for ring canal assembly and actin organization during Drosophila oogenesis. J Cell Biol 1999; 146:1061-74. [PMID: 10477759 PMCID: PMC2169474 DOI: 10.1083/jcb.146.5.1061] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/1999] [Accepted: 07/29/1999] [Indexed: 11/22/2022] Open
Abstract
The remodeling of the actin cytoskeleton is essential for cell migration, cell division, and cell morphogenesis. Actin-binding proteins play a pivotal role in reorganizing the actin cytoskeleton in response to signals exchanged between cells. In consequence, actin-binding proteins are increasingly a focus of investigations into effectors of cell signaling and the coordination of cellular behaviors within developmental processes. One of the first actin-binding proteins identified was filamin, or actin-binding protein 280 (ABP280). Filamin is required for cell migration (Cunningham et al. 1992), and mutations in human alpha-filamin (FLN1; Fox et al. 1998) are responsible for impaired migration of cerebral neurons and give rise to periventricular heterotopia, a disorder that leads to epilepsy and vascular disorders, as well as embryonic lethality. We report the identification and characterization of a mutation in Drosophila filamin, the homologue of human alpha-filamin. During oogenesis, filamin is concentrated in the ring canal structures that fortify arrested cleavage furrows and establish cytoplasmic bridges between cells of the germline. The major structural features common to other filamins are conserved in Drosophila filamin. Mutations in Drosophila filamin disrupt actin filament organization and compromise membrane integrity during oocyte development, resulting in female sterility. The genetic and molecular characterization of Drosophila filamin provides the first genetic model system for the analysis of filamin function and regulation during development.
Collapse
Affiliation(s)
- Min-gang Li
- Department of Genetics, Cell and Developmental Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Madeline Serr
- Department of Genetics, Cell and Developmental Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Kevin Edwards
- ERATO Yamamoto Behavior Genes Project, University of Hawaii, Honolulu, Hawaii 96822
| | - Susan Ludmann
- Department of Genetics, Cell and Developmental Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Daisuke Yamamoto
- ERATO Yamamoto Behavior Genes Project, Waseda University School of Human Sciences, Tokorozawa, Saitama 359-1192, Japan
| | - Lewis G. Tilney
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Christine M. Field
- Department of Biology, Harvard Medical School, Boston, Massachusetts 02115
| | - Thomas S. Hays
- Department of Genetics, Cell and Developmental Biology, University of Minnesota, St. Paul, Minnesota 55108
| |
Collapse
|
48
|
Abstract
We have used methods that have allowed simultaneous fluorescent staining of intracellular actin together with either myosin, filamin, or tubulin in normal rat kidney fibroblasts in monolayer culture. In the main portions of the cell body, the actin, myosin, and filamin are all present in two structures: in one, the three proteins are present in the same fiber bundles (stress fibers); in the other, there is a diffuse distribution of the three proteins. On portions of the cell periphery however-in the basal regions of microspikes, in ruffles, and in regions of cell-cell contact-actin and filamin are present, but myosin is severely depleted or absent. Microtubules are present in the cell body in a distribution independent of the stress fibers and are mostly absent from the cell periphery. Microspikes and ruffles are highly dynamic structures on the cell surface, and regions of cell-cell contact generally result from the association of ruffles on the two contacting cells. Therefore, the presence of filamin and actin but not myosin in these specialized regions on the cell surface, together with the recent demonstration [Wang, K. & Singer, S. J. (1977) Proc. Natl. Acad. Sci. USA 74, 2021-2025)] that pure filamin interacts with individual F-actin filaments in solution to form fiber bundles and sheet-like structures, suggest that in vivo filamin-actin interactions play an important role in the control of actin filament structure, in cell motility, and in the stabilization of cell-cell contacts.
Collapse
|