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Stojceski F, Buetti-Dinh A, Stoddart MJ, Danani A, Della Bella E, Grasso G. Influence of dexamethasone on the interaction between glucocorticoid receptor and SOX9: A molecular dynamics study. J Mol Graph Model 2023; 125:108587. [PMID: 37579519 DOI: 10.1016/j.jmgm.2023.108587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/16/2023]
Abstract
The glucocorticoid receptor (GR) is a nuclear receptor that controls critical biological processes by regulating the transcription of specific genes. GR transcriptional activity is modulated by a series of ligands and coenzymes, where a ligand can act as an agonist or antagonist. GR agonists, such as the glucocorticoids dexamethasone (DEX) and prednisolone, are widely prescribed to patients with inflammatory and autoimmune diseases. DEX is also used to induce osteogenic differentiation in vitro. Recently, it has been highlighted that DEX induces changes in the osteogenic differentiation of human mesenchymal stromal cells by downregulating the transcription factor SRY-box transcription factor 9 (SOX9) and upregulating the peroxisome proliferator-activated receptor γ (PPARG). SOX9 is fundamental in the control of chondrogenesis, but also in osteogenesis by acting as a dominant-negative of RUNX2. Many processes remain to be clarified during cell fate determination, such as the interplay between the key transcription factors. The main objective pursued by this work is to shed light on the interaction between GR and SOX9 in the presence and absence of DEX at an atomic level of resolution using molecular dynamics simulations. The outcome of this research could help the understanding of possible molecular interactions between GR and SOX9 and their role in the determination of cell fate. The results highlight the key residues at the interface between GR and SOX9 involved in the complexation process and shed light on the mechanism through which DEX modulates GR-SOX9 binding and exerts its biological activity.
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Affiliation(s)
- Filip Stojceski
- Dalle Molle Institute for Artificial Intelligence USI-SUPSI Polo universitario Lugano - Campus Est, Via la Santa 1, 6962, Lugano-Viganello, Switzerland
| | - Antoine Buetti-Dinh
- Dalle Molle Institute for Artificial Intelligence USI-SUPSI Polo universitario Lugano - Campus Est, Via la Santa 1, 6962, Lugano-Viganello, Switzerland
| | - Martin J Stoddart
- AO Research Institute Davos, Clavadelerstrasse 8, 7270, Davos Platz, Switzerland
| | - Andrea Danani
- Dalle Molle Institute for Artificial Intelligence USI-SUPSI Polo universitario Lugano - Campus Est, Via la Santa 1, 6962, Lugano-Viganello, Switzerland
| | - Elena Della Bella
- AO Research Institute Davos, Clavadelerstrasse 8, 7270, Davos Platz, Switzerland.
| | - Gianvito Grasso
- Dalle Molle Institute for Artificial Intelligence USI-SUPSI Polo universitario Lugano - Campus Est, Via la Santa 1, 6962, Lugano-Viganello, Switzerland.
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2
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Fadel L, Dacic M, Fonda V, Sokolsky BA, Quagliarini F, Rogatsky I, Uhlenhaut NH. Modulating glucocorticoid receptor actions in physiology and pathology: Insights from coregulators. Pharmacol Ther 2023; 251:108531. [PMID: 37717739 PMCID: PMC10841922 DOI: 10.1016/j.pharmthera.2023.108531] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/19/2023]
Abstract
Glucocorticoids (GCs) are a class of steroid hormones that regulate key physiological processes such as metabolism, immune function, and stress responses. The effects of GCs are mediated by the glucocorticoid receptor (GR), a ligand-dependent transcription factor that activates or represses the expression of hundreds to thousands of genes in a tissue- and physiological state-specific manner. The activity of GR is modulated by numerous coregulator proteins that interact with GR in response to different stimuli assembling into a multitude of DNA-protein complexes and facilitate the integration of these signals, helping GR to communicate with basal transcriptional machinery and chromatin. Here, we provide a brief overview of the physiological and molecular functions of GR, and discuss the roles of GR coregulators in the immune system, key metabolic tissues and the central nervous system. We also present an analysis of the GR interactome in different cells and tissues, which suggests tissue-specific utilization of GR coregulators, despite widespread functions shared by some of them.
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Affiliation(s)
- Lina Fadel
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Marija Dacic
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Physiology, Biophysics and Systems Biology, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Vlera Fonda
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Baila A Sokolsky
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Fabiana Quagliarini
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Inez Rogatsky
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA.
| | - N Henriette Uhlenhaut
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany; Metabolic Programming, TUM School of Life Sciences & ZIEL Institute for Food and Health, Gregor11 Mendel-Str. 2, 85354 Freising, Germany.
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3
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Chen TY, Lin NY, Wen CH, Lin CA, Venkatesan P, Wijerathna P, Lin CY, Lai PS. Development of triamcinolone acetonide-hyaluronic acid conjugates with selective targeting and less osteoporosis effect for rheumatoid arthritis treatments. Int J Biol Macromol 2023; 237:124047. [PMID: 36933598 DOI: 10.1016/j.ijbiomac.2023.124047] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 03/04/2023] [Accepted: 03/11/2023] [Indexed: 03/18/2023]
Abstract
Rheumatoid arthritis (RA) is a common systemic autoimmune disease in developed countries. In clinical treatment, steroids have been used as bridging and adjunctive therapy after disease-modifying anti-rheumatic drug administration. However, the severe side effects caused by the nonspecific targeting of organs followed by long-term administration have limited their usage in RA. In this study, poorly water-soluble triamcinolone acetonide (TA), a highly potent corticosteroid for intra-articular injection, is conjugated on hyaluronic acid (HA) for intravenous purposes with increased specific drug accumulation in inflamed parts for RA. Our results demonstrate that the designed HA/TA coupling reaction reveals >98 % conjugation efficiency in the dimethyl sulfoxide/water system, and the resulting HA-TA conjugates show lower osteoblastic apoptosis compared with that in free TA-treated osteoblast-like NIH3T3 cells. Furthermore, in a collagen-antibody-induced arthritis animal study, HA-TA conjugates enhanced the initiative targeting ability to inflame tissue and reduce the histopathological arthritic changes (score = 0). Additionally, the level of bone formation marker P1NP in HA-TA-treated ovariectomized mice (303.6 ± 40.6 pg/mL) is significantly higher than that in the free TA-treated group (143.1 ± 3.9 pg/mL), indicating the potential for osteoporotic reduction using an efficient HA conjugation strategy for the long-term administration of steroids against RA.
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Affiliation(s)
- Tzu-Yang Chen
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan; Basic Research Division, Holy Stone Healthcare Co., Ltd., 114 Taipei, Taiwan.
| | - Neng-Yu Lin
- Graduate Institute of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan.
| | - Chih-Hao Wen
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Chih-An Lin
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Parthiban Venkatesan
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Prasanna Wijerathna
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Chung-Yu Lin
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Ping-Shan Lai
- Department of Chemistry, National Chung Hsing University, Taichung 40227, Taiwan; Program of Tissue Engineering and Regenerative Medicine, National Chung Hsing University, Taichung 40227, Taiwan.
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4
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Jeanneteau F, Meijer OC, Moisan MP. Structural basis of glucocorticoid receptor signaling bias. J Neuroendocrinol 2023; 35:e13203. [PMID: 36221223 DOI: 10.1111/jne.13203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 09/15/2022] [Accepted: 09/23/2022] [Indexed: 11/30/2022]
Abstract
Dissociation between the healthy and toxic effects of cortisol, a major stress-responding hormone has been a widely used strategy to develop anti-inflammatory glucocorticoids with fewer side effects. Such strategy falls short when treating brain disorders as timing and activity state within large-scale neuronal networks determine the physiological and behavioral specificity of cortisol response. Advances in structural molecular dynamics posit the bases for engineering glucocorticoids with precision bias for select downstream signaling pathways. Design of allosteric and/or cooperative control for the glucocorticoid receptor could help promote the beneficial and reduce the deleterious effects of cortisol on brain and behavior in disease conditions.
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Affiliation(s)
- Freddy Jeanneteau
- Institut de génomique fonctionnelle, Université de Montpellier, INSERM, CNRS, Montpellier, France
| | - Onno C Meijer
- Leiden University Medical Center, Leiden, The Netherlands
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5
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Carceller-Zazo E, Sevilla LM, Pons-Alonso O, Chiner-Oms Á, Amazit L, An Vu T, Vitellius G, Viengchareun S, Comas I, Jaszczyszyn Y, Abella M, Alegre-Martí A, Estébanez-Perpiñá E, Lombès M, Pérez P. The mineralocorticoid receptor modulates timing and location of genomic binding by glucocorticoid receptor in response to synthetic glucocorticoids in keratinocytes. FASEB J 2023; 37:e22709. [PMID: 36527388 DOI: 10.1096/fj.202201199rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 11/29/2022] [Accepted: 12/02/2022] [Indexed: 12/23/2022]
Abstract
Glucocorticoids (GCs) exert potent antiproliferative and anti-inflammatory properties, explaining their therapeutic efficacy for skin diseases. GCs act by binding to the GC receptor (GR) and the mineralocorticoid receptor (MR), co-expressed in classical and non-classical targets including keratinocytes. Using knockout mice, we previously demonstrated that GR and MR exert essential nonoverlapping functions in skin homeostasis. These closely related receptors may homo- or heterodimerize to regulate transcription, and theoretically bind identical GC-response elements (GRE). We assessed the contribution of MR to GR genomic binding and the transcriptional response to the synthetic GC dexamethasone (Dex) using control (CO) and MR knockout (MREKO ) keratinocytes. GR chromatin immunoprecipitation (ChIP)-seq identified peaks common and unique to both genotypes upon Dex treatment (1 h). GREs, AP-1, TEAD, and p53 motifs were enriched in CO and MREKO peaks. However, GR genomic binding was 35% reduced in MREKO , with significantly decreased GRE enrichment, and reduced nuclear GR. Surface plasmon resonance determined steady state affinity constants, suggesting preferred dimer formation as MR-MR > GR-MR ~ GR-GR; however, kinetic studies demonstrated that GR-containing dimers had the longest lifetimes. Despite GR-binding differences, RNA-seq identified largely similar subsets of differentially expressed genes in both genotypes upon Dex treatment (3 h). However, time-course experiments showed gene-dependent differences in the magnitude of expression, which correlated with earlier and more pronounced GR binding to GRE sites unique to CO including near Nr3c1. Our data show that endogenous MR has an impact on the kinetics and differential genomic binding of GR, affecting the time-course, specificity, and magnitude of GC transcriptional responses in keratinocytes.
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Affiliation(s)
- Elena Carceller-Zazo
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Lisa M Sevilla
- Department of Pathology and Molecular and Cell Therapy, Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
| | - Omar Pons-Alonso
- Department of Pathology and Molecular and Cell Therapy, Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
| | - Álvaro Chiner-Oms
- Department of Genomics and Proteomics, Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
| | - Larbi Amazit
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France.,Unité Mixte de Service UMS-44, Le Kremlin Bicêtre, France
| | - Thi An Vu
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Géraldine Vitellius
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Say Viengchareun
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Iñaki Comas
- Department of Genomics and Proteomics, Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
| | - Yan Jaszczyszyn
- CEA, CNRS, Institute for Integrative Biology of the Cell, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Montserrat Abella
- Structural Biology of Nuclear Receptors, Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain.,Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
| | - Andrea Alegre-Martí
- Structural Biology of Nuclear Receptors, Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain.,Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
| | - Eva Estébanez-Perpiñá
- Structural Biology of Nuclear Receptors, Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain.,Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona, Barcelona, Spain
| | - Marc Lombès
- Inserm, Physiologie et Physiopathologie Endocriniennes, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Paloma Pérez
- Department of Pathology and Molecular and Cell Therapy, Instituto de Biomedicina de Valencia (IBV-CSIC), Valencia, Spain
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6
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Jiménez-Panizo A, Alegre-Martí A, Tettey T, Fettweis G, Abella M, Antón R, Johnson T, Kim S, Schiltz R, Núñez-Barrios I, Font-Díaz J, Caelles C, Valledor A, Pérez P, Rojas A, Fernández-Recio J, Presman D, Hager G, Fuentes-Prior P, Estébanez-Perpiñá E. The multivalency of the glucocorticoid receptor ligand-binding domain explains its manifold physiological activities. Nucleic Acids Res 2022; 50:13063-13082. [PMID: 36464162 PMCID: PMC9825158 DOI: 10.1093/nar/gkac1119] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 10/28/2022] [Accepted: 11/08/2022] [Indexed: 12/05/2022] Open
Abstract
The glucocorticoid receptor (GR) is a ubiquitously expressed transcription factor that controls metabolic and homeostatic processes essential for life. Although numerous crystal structures of the GR ligand-binding domain (GR-LBD) have been reported, the functional oligomeric state of the full-length receptor, which is essential for its transcriptional activity, remains disputed. Here we present five new crystal structures of agonist-bound GR-LBD, along with a thorough analysis of previous structural work. We identify four distinct homodimerization interfaces on the GR-LBD surface, which can associate into 20 topologically different homodimers. Biologically relevant homodimers were identified by studying a battery of GR point mutants including crosslinking assays in solution, quantitative fluorescence microscopy in living cells, and transcriptomic analyses. Our results highlight the relevance of non-canonical dimerization modes for GR, especially of contacts made by loop L1-3 residues such as Tyr545. Our work illustrates the unique flexibility of GR's LBD and suggests different dimeric conformations within cells. In addition, we unveil pathophysiologically relevant quaternary assemblies of the receptor with important implications for glucocorticoid action and drug design.
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Affiliation(s)
| | | | | | - Gregory Fettweis
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-5055, USA
| | - Montserrat Abella
- Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona (UB), 08028 Barcelona, Spain,Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona (UB), 08028 Barcelona, Spain
| | - Rosa Antón
- Biomedical Research Institute Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain
| | - Thomas A Johnson
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-5055, USA
| | - Sohyoung Kim
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-5055, USA
| | - R Louis Schiltz
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-5055, USA
| | - Israel Núñez-Barrios
- Andalusian Center for Developmental Biology (CABD-CSIC). Campus Universitario Pablo de Olavide, 41013 Sevilla, Spain
| | - Joan Font-Díaz
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona (UB), 08028 Barcelona, Spain,Department of Cell Biology, Physiology and Immunology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Carme Caelles
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona (UB), 08028 Barcelona, Spain,Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona 08028, Spain
| | - Annabel F Valledor
- Institute of Biomedicine of the University of Barcelona (IBUB), University of Barcelona (UB), 08028 Barcelona, Spain,Department of Cell Biology, Physiology and Immunology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Paloma Pérez
- Instituto de Biomedicina de Valencia (IBV)-CSIC, 46010, Valencia, Spain
| | - Ana M Rojas
- Andalusian Center for Developmental Biology (CABD-CSIC). Campus Universitario Pablo de Olavide, 41013 Sevilla, Spain
| | - Juan Fernández-Recio
- Instituto de Ciencias de la Vid y del Vino (ICVV), CSIC - Universidad de La Rioja - Gobierno de La Rioja, 26007 Logroño, Spain
| | - Diego M Presman
- IFIBYNE, UBA-CONICET, Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Buenos Aires C1428EGA, Argentina
| | - Gordon L Hager
- Correspondence may also be addressed to Gordon L. Hager. Tel: +1 240 760 6618;
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7
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Shi Y, Cao S, Ni D, Fan J, Lu S, Xue M. The Role of Conformational Dynamics and Allostery in the Control of Distinct Efficacies of Agonists to the Glucocorticoid Receptor. Front Mol Biosci 2022; 9:933676. [PMID: 35874618 PMCID: PMC9300934 DOI: 10.3389/fmolb.2022.933676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Glucocorticoid receptor (GR) regulates various cellular functions. Given its broad influence on metabolic activities, it has been the target of drug discovery for decades. However, how drugs induce conformational changes in GR has remained elusive. Herein, we used five GR agonists (dex, AZ938, pred, cor, and dibC) with different efficacies to investigate which aspect of the ligand induced the differences in efficacy. We performed molecular dynamics simulations on the five systems (dex-, AZ938-, pred-, cor-, and dibC-bound systems) and observed a distinct discrepancy in the conformation of the cofactor TIF2. Moreover, we discovered ligand-induced differences regarding the level of conformational changes posed by the binding of cofactor TIF2 and identified a pair of essential residues D590 and T39. We further found a positive correlation between the efficacies of ligands and the interaction of the two binding pockets' domains, where D590 and T739 were involved, implying their significance in the participation of allosteric communication. Using community network analysis, two essential communities containing D590 and T739 were identified with their connectivity correlating to the efficacy of ligands. The potential communication pathways between these two residues were revealed. These results revealed the underlying mechanism of allosteric communication between the ligand-binding and cofactor-binding pockets and identified a pair of important residues in the allosteric communication pathway, which can serve as a guide for future drug discovery.
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Affiliation(s)
- Yuxin Shi
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shu Cao
- Department of Urology, Ezhou Central Hospital, Hubei, China
| | - Duan Ni
- The Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Jigang Fan
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mintao Xue
- Department of Orthopedics, Second Affiliated Hospital of Naval Medical University, Shanghai, China
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8
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Structural insights into glucocorticoid receptor function. Biochem Soc Trans 2021; 49:2333-2343. [PMID: 34709368 DOI: 10.1042/bst20210419] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 09/30/2021] [Accepted: 10/04/2021] [Indexed: 01/02/2023]
Abstract
The glucocorticoid receptor (GR) is a steroid hormone-activated transcription factor that binds to various glucocorticoid response elements to up- or down- regulate the transcription of thousands of genes involved in metabolism, development, stress and inflammatory responses. GR consists of two domains enabling interaction with glucocorticoids, DNA response elements and coregulators, as well as a large intrinsically disordered region that mediates condensate formation. A growing body of structural studies during the past decade have shed new light on GR interactions, providing a new understanding of the mechanisms driving context-specific GR activity. Here, we summarize the established and emerging mechanisms of action of GR, primarily from a structural perspective. This minireview also discusses how the current state of knowledge of GR function may guide future glucocorticoid design with an improved therapeutic index for different inflammatory disorders.
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9
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Frank F, Liu X, Ortlund EA. Glucocorticoid receptor condensates link DNA-dependent receptor dimerization and transcriptional transactivation. Proc Natl Acad Sci U S A 2021; 118:e2024685118. [PMID: 34285072 PMCID: PMC8325269 DOI: 10.1073/pnas.2024685118] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The glucocorticoid receptor (GR) is a ligand-regulated transcription factor (TF) that controls the tissue- and gene-specific transactivation and transrepression of thousands of target genes. Distinct GR DNA-binding sequences with activating or repressive activities have been identified, but how they modulate transcription in opposite ways is not known. We show that GR forms phase-separated condensates that specifically concentrate known coregulators via their intrinsically disordered regions (IDRs) in vitro. A combination of dynamic, multivalent (between IDRs) and specific, stable interactions (between LxxLL motifs and the GR ligand-binding domain) control the degree of recruitment. Importantly, GR DNA binding directs the selective partitioning of coregulators within GR condensates such that activating DNAs cause enhanced recruitment of coactivators. Our work shows that condensation controls GR function by modulating coregulator recruitment and provides a mechanism for the up- and down-regulation of GR target genes controlled by distinct DNA recognition elements.
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Affiliation(s)
- Filipp Frank
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Xu Liu
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
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10
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Disruption of a key ligand-H-bond network drives dissociative properties in vamorolone for Duchenne muscular dystrophy treatment. Proc Natl Acad Sci U S A 2020; 117:24285-24293. [PMID: 32917814 DOI: 10.1073/pnas.2006890117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Duchenne muscular dystrophy is a genetic disorder that shows chronic and progressive damage to skeletal and cardiac muscle leading to premature death. Antiinflammatory corticosteroids targeting the glucocorticoid receptor (GR) are the current standard of care but drive adverse side effects such as deleterious bone loss. Through subtle modification to a steroidal backbone, a recently developed drug, vamorolone, appears to preserve beneficial efficacy but with significantly reduced side effects. We use combined structural, biophysical, and biochemical approaches to show that loss of a receptor-ligand hydrogen bond drives these remarkable therapeutic effects. Moreover, vamorolone uniformly weakens coactivator associations but not corepressor associations, implicating partial agonism as the main driver of its dissociative properties. Additionally, we identify a critical and evolutionarily conserved intramolecular network connecting the ligand to the coregulator binding surface. Interruption of this allosteric network by vamorolone selectively reduces GR-driven transactivation while leaving transrepression intact. Our results establish a mechanistic understanding of how vamorolone reduces side effects, guiding the future design of partial agonists as selective GR modulators with an improved therapeutic index.
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11
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Zhou Y, Chen B. GAS5‑mediated regulation of cell signaling (Review). Mol Med Rep 2020; 22:3049-3056. [PMID: 32945519 PMCID: PMC7453608 DOI: 10.3892/mmr.2020.11435] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022] Open
Abstract
In recent years, an increasing number of long non-coding RNAs (lncRNAs) have been discovered using microarrays and nucleic acid sequencing technology. LncRNAs exert crucial biological functions by regulating signaling pathways. In particular, the lncRNA growth arrest-specific transcript 5 (GAS5) has been documented to serve a crucial role in numerous signaling pathways. This article discusses the latest developments in the association between GAS5 and microRNA (miRNA), p53, mTOR, glucocorticoid response element (GRE) and AKT in order to investigate the roles served by GAS5. miRNAs can activate related signaling pathways and GAS5 can combine with miRNA to regulate related signaling pathways. GAS5 may regulate p53 expression via derivation of snoRNA, but the underlying mechanism requires further investigation. GAS5 overxpresion reduces the expression level of mTOR, which is induced by inhibiting miR-106a-5p expression. GAS5 is a sponge of GR, and serves a role in controlling and maintaining glucocorticoid sensitivity and drug resistance via competitive combination with GR. GAS5 can interact with miRNAs, such as miR-21 and miR-532-5p, to regulate the expression of AKT signaling pathway, affecting cell survival and apoptosis. Collectively, the data indicate that GAS5 serves a key role in the miRNA, p53, mTOR, GRE, and AKT signaling pathways. GAS5 regulates complex intracellular signaling pathways primarily through three modes of action, all of which are interrelated: Signal, decoy and guide. In the present article, latest developments in the association between GAS5 and a number of cellular signaling pathways are discussed to examine the tumor suppressive role of GAS5.
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Affiliation(s)
- Yang Zhou
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212000, P.R. China
| | - Binghai Chen
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212000, P.R. China
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12
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Hoeflich A, Fitzner B, Walz C, Hecker M, Tuchscherer A, Bastian M, Brenmoehl J, Schröder I, Willenberg HS, Reincke M, Zettl UK. Systemic Effects by Intrathecal Administration of Triamcinolone Acetonide in Patients With Multiple Sclerosis. Front Endocrinol (Lausanne) 2020; 11:574. [PMID: 32982971 PMCID: PMC7481359 DOI: 10.3389/fendo.2020.00574] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/14/2020] [Indexed: 12/11/2022] Open
Abstract
In patients suffering from multiple sclerosis (MS), intrathecal injection of triamcinolone acetonide (TCA) has been shown to improve symptoms of spasticity. Although repeated intrathecal injection of TCA has been used in a number of studies in late-stage MS patients with spinal cord involvement, no clinical-chemical data are available on the distribution of TCA in cerebrospinal fluid (CSF) or serum. Moreover, the effects of intrathecal TCA administration on the concentrations of endogenous steroids remain poorly understood. Therefore, we have quantified TCA and selected endogenous steroids in CSF and serum of TCA-treated MS patients suffering from spasticity. Concentrations of steroids were quantified by LC-MS, ELISA, or ECLIA and compared with the blood-brain barrier status, diagnosed with the Reibergram. The concentration of TCA in CSF significantly increased during each treatment cycle up to >5 μg/ml both in male and female patients (p < 0.001). Repeated TCA administration also evoked serum concentrations of TCA up to >30 ng/ml (p < 0.001) and severely depressed serum levels of cortisol and corticosterone (p < 0.001). In addition, concentrations of circulating estrogen were significantly suppressed (p < 0.001). Due to the potent suppressive effects of TCA on steroid hormone concentrations both in the brain and in the periphery, we recommend careful surveillance of adrenal function following repeated intrathecal TCA injections in MS patients.
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Affiliation(s)
- Andreas Hoeflich
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
- *Correspondence: Andreas Hoeflich
| | - Brit Fitzner
- Neuroimmunological Section, Department of Neurology, Rostock University Medical Center, Rostock, Germany
| | - Christina Walz
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Michael Hecker
- Neuroimmunological Section, Department of Neurology, Rostock University Medical Center, Rostock, Germany
| | - Armin Tuchscherer
- Institute of Genetics and Biometry, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Manuela Bastian
- Institute for Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, Rostock, Germany
| | - Julia Brenmoehl
- Institute of Genome Biology, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Ina Schröder
- Neuroimmunological Section, Department of Neurology, Rostock University Medical Center, Rostock, Germany
| | - Holger S. Willenberg
- Division of Endocrinology and Metabolism, Rostock University Medical Center, Rostock, Germany
| | - Martin Reincke
- Department of Endocrinology, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, München, Germany
| | - Uwe Klaus Zettl
- Neuroimmunological Section, Department of Neurology, Rostock University Medical Center, Rostock, Germany
- Uwe Klaus Zettl
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Liu X, Wang Y, Ortlund EA. First High-Resolution Crystal Structures of the Glucocorticoid Receptor Ligand-Binding Domain-Peroxisome Proliferator-Activated γ Coactivator 1- α Complex with Endogenous and Synthetic Glucocorticoids. Mol Pharmacol 2019; 96:408-417. [PMID: 31391291 PMCID: PMC6724573 DOI: 10.1124/mol.119.116806] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/30/2019] [Indexed: 11/22/2022] Open
Abstract
Both synthetic and endogenous glucocorticoids are important pharmaceutic drugs known to bind to the ligand-binding domain (LBD) of glucocorticoid receptor (GR), a member of the nuclear receptor (NR) superfamily. Ligand binding induces conformational changes within GR, resulting in subsequent DNA binding and differential coregulator recruitment, ultimately activating or repressing target gene expression. One of the most crucial coregulators is peroxisome proliferator-activated γ coactivator 1-α (PGC1α), which acts to regulate energy metabolism by directly interacting with GR to modulate gene expression. However, the mechanisms through which PGC1α senses GR conformation to drive transcription are not completely known. Here, an ancestral variant of the GR (AncGR2) LBD was used as a tool to produce stable protein for biochemical and structural studies. PGC1α is found to interact more tightly and form a more stable complex with AncGR2 LBD than nuclear receptor coactivator 2. We report the first high-resolution X-ray crystal structures of AncGR2 LBD in complex with PGC1α and dexamethasone (DEX) or hydrocortisone (HCY). Structural analyses reveal how distinct steroid drugs bind to GR with different affinities by unique hydrogen bonds and hydrophobic interactions. Important charge clamps are formed between the activation function 2 and PGC1α to mediate their specific interactions. These interactions lead to a high level of protection from hydrogen-deuterium exchange at the coregulator interaction site and strong intramolecular allosteric communication to ligand binding site. This is the first structure detailing the GR-PGC1α interaction providing a foundation for future design of specific therapeutic agents targeting these critical metabolic regulators. SIGNIFICANCE STATEMENT: High-resolution structures of AncGR2 LBD bound to DEX and HCY in complex with PGC1α reveal the molecular mechanism of PGC1α binding to AncGR2 LBD as well as the distinct affinities between DEX and HCY binding. Identifying the structural mechanisms that drive drug affinity is of pharmacologic interest to the glucocorticoid receptor field as an avenue to guide future drug design targeting GR-PGC1α signaling, which plays a crucial role in controlling hepatic glucose output.
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Affiliation(s)
- Xu Liu
- Department of Biochemistry, Emory University School of Medicine, Atlanta Georgia (X.L., Y.W., E.A.O.) and College of Life Sciences, Qingdao University, Qingdao, People's Republic of China (Y.W.)
| | - Yashuo Wang
- Department of Biochemistry, Emory University School of Medicine, Atlanta Georgia (X.L., Y.W., E.A.O.) and College of Life Sciences, Qingdao University, Qingdao, People's Republic of China (Y.W.)
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta Georgia (X.L., Y.W., E.A.O.) and College of Life Sciences, Qingdao University, Qingdao, People's Republic of China (Y.W.)
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14
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Single-molecule force spectroscopy reveals folding steps associated with hormone binding and activation of the glucocorticoid receptor. Proc Natl Acad Sci U S A 2018; 115:11688-11693. [PMID: 30366952 DOI: 10.1073/pnas.1807618115] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The glucocorticoid receptor (GR) is a prominent nuclear receptor linked to a variety of diseases and an important drug target. Binding of hormone to its ligand binding domain (GR-LBD) is the key activation step to induce signaling. This process is tightly regulated by the molecular chaperones Hsp70 and Hsp90 in vivo. Despite its importance, little is known about GR-LBD folding, the ligand binding pathway, or the requirement for chaperone regulation. In this study, we have used single-molecule force spectroscopy by optical tweezers to unravel the dynamics of the complete pathway of folding and hormone binding of GR-LBD. We identified a "lid" structure whose opening and closing is tightly coupled to hormone binding. This lid is located at the N terminus without direct contacts to the hormone. Under mechanical load, apo-GR-LBD folds stably and readily without the need of chaperones with a folding free energy of [Formula: see text] The folding pathway is largely independent of the presence of hormone. Hormone binds only in the last step and lid closure adds an additional [Formula: see text] of free energy, drastically increasing the affinity. However, mechanical double-jump experiments reveal that, at zero force, GR-LBD folding is severely hampered by misfolding, slowing it to less than 1·s-1 From the force dependence of the folding rates, we conclude that the misfolding occurs late in the folding pathway. These features are important cornerstones for understanding GR activation and its tight regulation by chaperones.
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15
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Bamberg K, Johansson U, Edman K, William-Olsson L, Myhre S, Gunnarsson A, Geschwindner S, Aagaard A, Björnson Granqvist A, Jaisser F, Huang Y, Granberg KL, Jansson-Löfmark R, Hartleib-Geschwindner J. Preclinical pharmacology of AZD9977: A novel mineralocorticoid receptor modulator separating organ protection from effects on electrolyte excretion. PLoS One 2018; 13:e0193380. [PMID: 29474466 PMCID: PMC5825103 DOI: 10.1371/journal.pone.0193380] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Accepted: 02/11/2018] [Indexed: 11/23/2022] Open
Abstract
Excess mineralocorticoid receptor (MR) activation promotes target organ dysfunction, vascular injury and fibrosis. MR antagonists like eplerenone are used for treating heart failure, but their use is limited due to the compound class-inherent hyperkalemia risk. Here we present evidence that AZD9977, a first-in-class MR modulator shows cardio-renal protection despite a mechanism-based reduced liability to cause hyperkalemia. AZD9977 in vitro potency and binding mode to MR were characterized using reporter gene, binding, cofactor recruitment assays and X-ray crystallopgraphy. Organ protection was studied in uni-nephrectomised db/db mice and uni-nephrectomised rats administered aldosterone and high salt. Acute effects of single compound doses on urinary electrolyte excretion were tested in rats on a low salt diet. AZD9977 and eplerenone showed similar human MR in vitro potencies. Unlike eplerenone, AZD9977 is a partial MR antagonist due to its unique interaction pattern with MR, which results in a distinct recruitment of co-factor peptides when compared to eplerenone. AZD9977 dose dependently reduced albuminuria and improved kidney histopathology similar to eplerenone in db/db uni-nephrectomised mice and uni-nephrectomised rats. In acute testing, AZD9977 did not affect urinary Na+/K+ ratio, while eplerenone increased the Na+/K+ ratio dose dependently. AZD9977 is a selective MR modulator, retaining organ protection without acute effect on urinary electrolyte excretion. This predicts a reduced hyperkalemia risk and AZD9977 therefore has the potential to deliver a safe, efficacious treatment to patients prone to hyperkalemia.
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MESH Headings
- Administration, Oral
- Aldosterone
- Animals
- Benzoates/chemistry
- Benzoates/pharmacokinetics
- Benzoates/pharmacology
- Cell Line, Tumor
- Dose-Response Relationship, Drug
- Drug Evaluation, Preclinical
- Eplerenone
- Humans
- Kidney/drug effects
- Kidney/metabolism
- Kidney/pathology
- Male
- Mice, Mutant Strains
- Mineralocorticoid Receptor Antagonists/chemistry
- Mineralocorticoid Receptor Antagonists/pharmacokinetics
- Mineralocorticoid Receptor Antagonists/pharmacology
- Molecular Structure
- Oxazines/chemistry
- Oxazines/pharmacokinetics
- Oxazines/pharmacology
- Potassium/urine
- Rats, Sprague-Dawley
- Receptors, Mineralocorticoid/genetics
- Receptors, Mineralocorticoid/metabolism
- Renal Insufficiency, Chronic/drug therapy
- Renal Insufficiency, Chronic/metabolism
- Renal Insufficiency, Chronic/pathology
- Sodium/urine
- Sodium, Dietary
- Spironolactone/analogs & derivatives
- Spironolactone/chemistry
- Spironolactone/pharmacokinetics
- Spironolactone/pharmacology
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Affiliation(s)
- Krister Bamberg
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Ulrika Johansson
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Karl Edman
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lena William-Olsson
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Susanna Myhre
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anders Gunnarsson
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Stefan Geschwindner
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anna Aagaard
- Discovery Sciences, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anna Björnson Granqvist
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Frédéric Jaisser
- Centre de Recherche des Cordeliers, INSERM U1138 Team 1, Paris, France
| | - Yufeng Huang
- Division of Nephrology & Hypertension, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Kenneth L. Granberg
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Rasmus Jansson-Löfmark
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Judith Hartleib-Geschwindner
- Cardiovascular, Renal and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden
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16
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Francis JW, Goswami D, Novick SJ, Pascal BD, Weikum ER, Ortlund EA, Griffin PR, Kahn RA. Nucleotide Binding to ARL2 in the TBCD∙ARL2∙β-Tubulin Complex Drives Conformational Changes in β-Tubulin. J Mol Biol 2017; 429:3696-3716. [PMID: 28970104 DOI: 10.1016/j.jmb.2017.09.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 08/31/2017] [Accepted: 09/26/2017] [Indexed: 11/25/2022]
Abstract
Microtubules are highly dynamic tubulin polymers that are required for a variety of cellular functions. Despite the importance of a cellular population of tubulin dimers, we have incomplete information about the mechanisms involved in the biogenesis of αβ-tubulin heterodimers. In addition to prefoldin and the TCP-1 Ring Complex, five tubulin-specific chaperones, termed cofactors A-E (TBCA-E), and GTP are required for the folding of α- and β-tubulin subunits and assembly into heterodimers. We recently described the purification of a novel trimer, TBCD•ARL2•β-tubulin. Here, we employed hydrogen/deuterium exchange coupled with mass spectrometry to explore the dynamics of each of the proteins in the trimer. Addition of guanine nucleotides resulted in changes in the solvent accessibility of regions of each protein that led to predictions about each's role in tubulin folding. Initial testing of that model confirmed that it is ARL2, and not β-tubulin, that exchanges GTP in the trimer. Comparisons of the dynamics of ARL2 monomer to ARL2 in the trimer suggested that its protein interactions were comparable to those of a canonical GTPase with an effector. This was supported by the use of nucleotide-binding assays that revealed an increase in the affinity for GTP by ARL2 in the trimer. We conclude that the TBCD•ARL2•β-tubulin complex represents a functional intermediate in the β-tubulin folding pathway whose activity is regulated by the cycling of nucleotides on ARL2. The co-purification of guanine nucleotide on the β-tubulin in the trimer is also shown, with implications to modeling the pathway.
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Affiliation(s)
- Joshua W Francis
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Devrishi Goswami
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States
| | - Scott J Novick
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States
| | - Bruce D Pascal
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States
| | - Emily R Weikum
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Patrick R Griffin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, United States
| | - Richard A Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, United States.
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