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Raineri D, Chiocchetti A, Cappellano G. Beyond the Biomarker: Unveiling the Multifaceted Role of Osteopontin in Both Physiological and Pathological Processes. Biomedicines 2024; 12:982. [PMID: 38790944 PMCID: PMC11117741 DOI: 10.3390/biomedicines12050982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 04/28/2024] [Indexed: 05/26/2024] Open
Abstract
Osteopontin (OPN), a multifunctional protein, has emerged as a fascinating subject of study due to its diverse roles in various physiological and pathological processes [...].
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Affiliation(s)
- Davide Raineri
- Department of Health Sciences, Interdisciplinary Research Center of Autoimmune Diseases-IRCAD, Università del Piemonte Orientale, 28100 Novara, Italy; (D.R.); (A.C.)
- Center for Translational Research on Autoimmune and Allergic Diseases-CAAD, Università del Piemonte Orientale, 28100 Novara, Italy
| | - Annalisa Chiocchetti
- Department of Health Sciences, Interdisciplinary Research Center of Autoimmune Diseases-IRCAD, Università del Piemonte Orientale, 28100 Novara, Italy; (D.R.); (A.C.)
- Center for Translational Research on Autoimmune and Allergic Diseases-CAAD, Università del Piemonte Orientale, 28100 Novara, Italy
| | - Giuseppe Cappellano
- Department of Health Sciences, Interdisciplinary Research Center of Autoimmune Diseases-IRCAD, Università del Piemonte Orientale, 28100 Novara, Italy; (D.R.); (A.C.)
- Center for Translational Research on Autoimmune and Allergic Diseases-CAAD, Università del Piemonte Orientale, 28100 Novara, Italy
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2
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Ackmann J, Brüge A, Gotina L, Lim S, Jahreis K, Vollbrecht AL, Kim YK, Pae AN, Labus J, Ponimaskin E. Structural determinants for activation of the Tau kinase CDK5 by the serotonin receptor 5-HT7R. Cell Commun Signal 2024; 22:233. [PMID: 38641599 PMCID: PMC11031989 DOI: 10.1186/s12964-024-01612-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 04/11/2024] [Indexed: 04/21/2024] Open
Abstract
BACKGROUND Multiple neurodegenerative diseases are induced by the formation and deposition of protein aggregates. In particular, the microtubule-associated protein Tau leads to the development of so-called tauopathies characterized by the aggregation of hyperphosphorylated Tau within neurons. We recently showed that the constitutive activity of the serotonin receptor 7 (5-HT7R) is required for Tau hyperphosphorylation and aggregation through activation of the cyclin-dependent kinase 5 (CDK5). We also demonstrated physical interaction between 5-HT7R and CDK5 at the plasma membrane suggesting that the 5-HT7R/CDK5 complex is an integral part of the signaling network involved in Tau-mediated pathology. METHODS Using biochemical, microscopic, molecular biological, computational and AI-based approaches, we investigated structural requirements for the formation of 5-HT7R/CDK5 complex. RESULTS We demonstrated that 5-HT7R domains responsible for coupling to Gs proteins are not involved in receptor interaction with CDK5. We also created a structural model of the 5-HT7R/CDK5 complex and refined the interaction interface. The model predicted two conserved phenylalanine residues, F278 and F281, within the third intracellular loop of 5-HT7R to be potentially important for complex formation. While site-directed mutagenesis of these residues did not influence Gs protein-mediated receptor signaling, replacement of both phenylalanines by alanine residues significantly reduced 5-HT7R/CDK5 interaction and receptor-mediated CDK5 activation, leading to reduced Tau hyperphosphorylation and aggregation. Molecular dynamics simulations of 5-HT7R/CDK5 complex for wild-type and receptor mutants confirmed binding interface stability of the initial model. CONCLUSIONS Our results provide a structural basis for the development of novel drugs targeting the 5-HT7R/CDK5 interaction interface for the selective treatment of Tau-related disorders, including frontotemporal dementia and Alzheimer's disease.
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Affiliation(s)
- Jana Ackmann
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Alina Brüge
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Lizaveta Gotina
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Sungsu Lim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Kathrin Jahreis
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Anna-Lena Vollbrecht
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Yun Kyung Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Ae Nim Pae
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Josephine Labus
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Evgeni Ponimaskin
- Department of Cellular Neurophysiology, Institute for Neurophysiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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Maggio R, Fasciani I, Petragnano F, Coppolino MF, Scarselli M, Rossi M. Unraveling the Functional Significance of Unstructured Regions in G Protein-Coupled Receptors. Biomolecules 2023; 13:1431. [PMID: 37892113 PMCID: PMC10604838 DOI: 10.3390/biom13101431] [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: 08/30/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 10/29/2023] Open
Abstract
Unstructured regions in functional proteins have gained attention in recent years due to advancements in informatics tools and biophysical methods. G protein-coupled receptors (GPCRs), a large family of cell surface receptors, contain unstructured regions in the form of the i3 loop and C-terminus. This review provides an overview of the functional significance of these regions in GPCRs. GPCRs transmit signals from the extracellular environment to the cell interior, regulating various physiological processes. The i3 loop, located between the fifth and sixth transmembrane helices, and the C-terminus, connected to the seventh transmembrane helix, are determinant of interactions with G proteins and with other intracellular partners such as arrestins. Recent studies demonstrate that the i3 loop and C-terminus play critical roles in allosterically regulating GPCR activation. They can act as autoregulators, adopting conformations that, by restricting G protein access, modulate receptor coupling specificity. The length and unstructured nature of the i3 loop and C-terminus provide unique advantages in GPCR interactions with intracellular protein partners. They act as "fishing lines", expanding the radius of interaction and enabling GPCRs to tether scaffolding proteins, thus facilitating receptor stability during cell membrane movements. Additionally, the i3 loop may be involved in domain swapping between GPCRs, generating novel receptor dimers with distinct binding and coupling characteristics. Overall, the i3 loop and C-terminus are now widely recognized as crucial elements in GPCR function and regulation. Understanding their functional roles enhances our comprehension of GPCR structure and signaling complexity and holds promise for advancements in receptor pharmacology and drug development.
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Affiliation(s)
- Roberto Maggio
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (M.R.)
| | - Irene Fasciani
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (M.R.)
| | - Francesco Petragnano
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (M.R.)
| | - Maria Francesca Coppolino
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy;
| | - Marco Scarselli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy;
| | - Mario Rossi
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (M.R.)
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4
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Intrinsically disordered proteins and proteins with intrinsically disordered regions in neurodegenerative diseases. Biophys Rev 2022; 14:679-707. [DOI: 10.1007/s12551-022-00968-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 05/28/2022] [Indexed: 12/14/2022] Open
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Li J, Remington JM, Liao C, Parsons RL, Schneebeli S, Braas KM, May V, Brewer M. GPCR Intracellular Loop Regulation of Beta-Arrestin-Mediated Endosomal Signaling Dynamics. J Mol Neurosci 2022; 72:1358-1373. [PMID: 35538393 PMCID: PMC9311399 DOI: 10.1007/s12031-022-02016-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 04/22/2022] [Indexed: 12/22/2022]
Abstract
G protein-coupled receptors (GPCRs) are currently appreciated to be routed to diverse cellular platforms to generate both G protein-dependent and -independent signals. The latter has been best studied with respect to β-arrestin-associated receptor internalization and trafficking to signaling endosomes for extracellular signal-regulated kinase (ERK) activation. However, how GPCR structural and conformational variants regulate endosomal ERK signaling dynamics, which can be central in neural development, plasticity, and disease processes, is not well understood. Among class B GPCRs, the PACAP-selective PAC1 receptor is unique in the expression of variants that can contain intracellular loop 3 (ICL3) cassette inserts. The nervous system expresses preferentially the PAC1Null (no insert) and PAC1Hop (28-amino acid Hop insert) receptor variants. Our molecular modeling and signaling studies revealed that the PAC1Null and PAC1Hop receptor variants can associate with β-arrestin differentially, resulting in enhanced receptor internalization and ERK activation for the PAC1Hop variant. The study amplifies our understandings of GPCR intracellular loop structure/function relationships with the first example of how the duration of endosomal ERK activation can be guided by ICL3. The results provide a framework for how changes in GPCR variant expression can impact developmental and homeostatic processes and may be contributory to maladaptive neuroplasticity underlying chronic pain and stress-related disorders.
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Affiliation(s)
- Jianing Li
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT, 05405, USA.
| | - Jacob M Remington
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT, 05405, USA
| | - Chenyi Liao
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT, 05405, USA
| | - Rodney L Parsons
- Department of Neurological Sciences, University of Vermont College of Medicine, 149 Beaumont Avenue, Burlington, VT, 05405, USA
| | - Severin Schneebeli
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT, 05405, USA
| | - Karen M Braas
- Department of Neurological Sciences, University of Vermont College of Medicine, 149 Beaumont Avenue, Burlington, VT, 05405, USA
| | - Victor May
- Department of Neurological Sciences, University of Vermont College of Medicine, 149 Beaumont Avenue, Burlington, VT, 05405, USA.
| | - Matthias Brewer
- Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT, 05405, USA
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Afza F, Singh N, Shriya S, Bisoyi P, Kashyap AK, Jain BP. Genome wide identification and analysis of WD40 domain containing proteins in Danio rerio. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2021.101426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Obot DN, Udom GJ, Udoh AE, Onyeukwu NJ, Olusola AJ, Udoh IM, Umana IK, Yemitan OK, Okokon JE. Advances in the molecular understanding of G protein-coupled receptors and their future therapeutic opportunities. FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2021. [DOI: 10.1186/s43094-021-00341-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Abstract
Background
Understanding the mechanisms, activated and inhibited pathways as well as other molecular targets involved in existing and emerging disease conditions provides useful insights into their proper diagnosis and treatment and aids drug discovery, development and production. G protein-coupled receptors (GPCRs) are one of the most important classes of targets for small-molecule drug discovery. Of all drug targets, GPCRs are the most studied, undoubtedly because of their pharmacological tractability and role in the pathophysiology as well as the pathogenesis of human diseases.
Main body of the abstract
GPCRs are regarded as the largest target class of the “druggable genome” representing approximately 19% of the currently available drug targets. They have long played a prominent role in drug discovery, such that as of this writing, 481 drugs (about 34% of all FDA-approved drugs) act on GPCRs. More than 320 therapeutic agents are currently under clinical trials, of which a significant percentage targets novel GPCRs. GPCRs are implicated in a wide variety of diseases including CNS disorders, inflammatory diseases such as rheumatoid arthritis and Crohn’s disease, as well as metabolic disease and cancer. The non-olfactory human GPCRs yet to be clinically explored or tried are endowed with perhaps a huge untapped potential drug discovery especially in the field of immunology and genetics.
Short conclusion
This review discusses the recent advances in the molecular pharmacology and future opportunities for targeting GPCRs with a view to drug development.
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Lysophosphatidic Acid Signaling in Cancer Cells: What Makes LPA So Special? Cells 2021; 10:cells10082059. [PMID: 34440828 PMCID: PMC8394178 DOI: 10.3390/cells10082059] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/06/2021] [Accepted: 08/07/2021] [Indexed: 12/13/2022] Open
Abstract
Lysophosphatidic acid (LPA) refers to a family of simple phospholipids that act as ligands for G protein-coupled receptors. While LPA exerts effects throughout the body in normal physiological circumstances, its pathological role in cancer is of great interest from a therapeutic viewpoint. The numerous LPA receptors (LPARs) are coupled to a variety of G proteins, and more than one LPAR is typically expressed on any given cell. While the individual receptors signal through conventional GPCR pathways, LPA is particularly efficacious in stimulating cancer cell proliferation and migration. This review addresses the mechanistic aspects underlying these pro-tumorigenic effects. We provide examples of LPA signaling responses in various types of cancers, with an emphasis on those where roles have been identified for specific LPARs. While providing an overview of LPAR signaling, these examples also reveal gaps in our knowledge regarding the mechanisms of LPA action at the receptor level. The current understanding of the LPAR structure and the roles of LPAR interactions with other receptors are discussed. Overall, LPARs provide insight into the potential molecular mechanisms that underlie the ability of individual GPCRs (or combinations of GPCRs) to elicit a unique spectrum of responses from their agonist ligands. Further knowledge of these mechanisms will inform drug discovery, since GPCRs are promising therapeutic targets for cancer.
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9
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Polarity scaffolds signaling in epithelial cell permeability. Inflamm Res 2021; 70:525-538. [PMID: 33721031 DOI: 10.1007/s00011-021-01454-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 01/20/2021] [Accepted: 03/06/2021] [Indexed: 01/14/2023] Open
Abstract
As an integral part of the innate immune system, the epithelial membrane is exposed to an array of insults that may trigger an immune response. One of the immune system's main functions is to regulate the level of communications between the mucosa and the lumen of various tissues. While it is clear that inhaled or ingested substances, or microorganisms may induce changes that affect the epithelial barrier in various ways, the proteins involved in the signaling cascades and physiological events leading to the regulation and maintenance of the barrier are not always well characterized. We review here some of the signaling components involved in regulating the barrier's paracellular permeability, and their potential effects on the activation of an immune response. While an effective immune response must be launched against pathogenic insults, tolerance must also be maintained for non-pathogenic antigens such as those in the commensal flora or for endogenous metabolites. Along with other members of the innate and adaptive immunity, the endocannabinoid system also plays an instrumental role in maintaining the balance between inflammation and tolerance. We discuss the potential effects of endo- and phytocannabinoids on epithelial permeability and how the dysregulation of this system could be involved in diseases and targeted for therapy.
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10
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Biosynthesis of lanthionine-constrained agonists of G protein-coupled receptors. Biochem Soc Trans 2020; 48:2195-2203. [PMID: 33125486 PMCID: PMC7609037 DOI: 10.1042/bst20200427] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 02/07/2023]
Abstract
The conformation with which natural agonistic peptides interact with G protein-coupled receptor(s) (GPCR(s)) partly results from intramolecular interactions such as hydrogen bridges or is induced by ligand–receptor interactions. The conformational freedom of a peptide can be constrained by intramolecular cross-links. Conformational constraints enhance the receptor specificity, may lead to biased activity and confer proteolytic resistance to peptidic GPCR agonists. Chemical synthesis allows to introduce a variety of cross-links into a peptide and is suitable for bulk production of relatively simple lead peptides. Lanthionines are thioether bridged alanines of which the two alanines can be introduced at different distances in chosen positions in a peptide. Thioether bridges are much more stable than disulfide bridges. Biosynthesis of lanthionine-constrained peptides exploiting engineered Gram-positive or Gram-negative bacteria that contain lanthionine-introducing enzymes constitutes a convenient method for discovery of lanthionine-stabilized GPCR agonists. The presence of an N-terminal leader peptide enables dehydratases to dehydrate serines and threonines in the peptide of interest after which a cyclase can couple the formed dehydroamino acids to cysteines forming (methyl)lanthionines. The leader peptide also guides the export of the formed lanthionine-containing precursor peptide out of Gram-positive bacteria via a lanthipeptide transporter. An engineered cleavage site in the C-terminus of the leader peptide allows to cleave off the leader peptide yielding the modified peptide of interest. Lanthipeptide GPCR agonists are an emerging class of therapeutics of which a few examples have demonstrated high efficacy in animal models of a variety of diseases. One lanthipeptide GPCR agonist has successfully passed clinical Phase Ia.
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White CW, Caspar B, Vanyai HK, Pfleger KDG, Hill SJ. CRISPR-Mediated Protein Tagging with Nanoluciferase to Investigate Native Chemokine Receptor Function and Conformational Changes. Cell Chem Biol 2020; 27:499-510.e7. [PMID: 32053779 PMCID: PMC7242902 DOI: 10.1016/j.chembiol.2020.01.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/02/2020] [Accepted: 01/24/2020] [Indexed: 02/07/2023]
Abstract
G protein-coupled receptors are a major class of membrane receptors that mediate physiological and pathophysiological cellular signaling. Many aspects of receptor activation and signaling can be investigated using genetically encoded luminescent fusion proteins. However, the use of these biosensors in live cell systems requires the exogenous expression of the tagged protein of interest. To maintain the normal cellular context here we use CRISPR/Cas9-mediated homology-directed repair to insert luminescent tags into the endogenous genome. Using NanoLuc and bioluminescence resonance energy transfer we demonstrate fluorescent ligand binding at genome-edited chemokine receptors. We also demonstrate that split-NanoLuc complementation can be used to investigate conformational changes and internalization of CXCR4 and that recruitment of β-arrestin2 to CXCR4 can be monitored when both proteins are natively expressed. These results show that genetically encoded luminescent biosensors can be used to investigate numerous aspects of receptor function at native expression levels.
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Affiliation(s)
- Carl W White
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK; Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, WA 6009, Australia; Australian Research Council Centre for Personalised Therapeutics Technologies, Australia.
| | - Birgit Caspar
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK
| | - Hannah K Vanyai
- Epithelial Biology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Kevin D G Pfleger
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, WA 6009, Australia; Australian Research Council Centre for Personalised Therapeutics Technologies, Australia; Dimerix Limited, Nedlands, WA 6009, Australia
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK; Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, WA 6009, Australia.
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Bruder M, Polo G, Trivella DBB. Natural allosteric modulators and their biological targets: molecular signatures and mechanisms. Nat Prod Rep 2020; 37:488-514. [PMID: 32048675 DOI: 10.1039/c9np00064j] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: 2008 to 2018Over the last decade more than two hundred single natural products were confirmed as natural allosteric modulators (alloNPs) of proteins. The compounds are presented and discussed with the support of a chemical space, constructed using a principal component analysis (PCA) of molecular descriptors from chemical compounds of distinct databases. This analysis showed that alloNPs are dispersed throughout the majority of the chemical space defined by natural products in general. Moreover, a cluster of alloNPs was shown to occupy a region almost devoid of allosteric modulators retrieved from a dataset composed mainly of synthetic compounds, further highlighting the importance to explore the entire natural chemical space for probing allosteric mechanisms. The protein targets which alloNPs bind to comprised 81 different proteins, which were classified into 5 major groups, with enzymes, in particular hydrolases, being the main representative group. The review also brings a critical interpretation on the mechanisms by which alloNPs display their molecular action on proteins. In the latter analysis, alloNPs were classified according to their final effect on the target protein, resulting in 3 major categories: (i) local alteration of the orthosteric site; (ii) global alteration in protein dynamics that change function; and (iii) oligomer stabilisation or protein complex destabilisation via protein-protein interaction in sites distant from the orthosteric site. G-protein coupled receptors (GPCRs), which use a combination of the three types of allosteric regulation found, were also probed by natural products. In summary, the natural allosteric modulators reviewed herein emphasise their importance for exploring alternative chemotherapeutic strategies, potentially pushing the boundaries of the druggable space of pharmacologically relevant drug targets.
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Affiliation(s)
- Marjorie Bruder
- Brazilian Biosciences National Laboratory (LNBio), National Centre for Research in Energy and Materials (CNPEM), 13083-970 Campinas, SP, Brazil.
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Mahmod Al-Qattan MN, Mordi MN. Molecular Basis of Modulating Adenosine Receptors Activities. Curr Pharm Des 2019; 25:817-831. [DOI: 10.2174/1381612825666190304122624] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 02/26/2019] [Indexed: 01/04/2023]
Abstract
Modulating cellular processes through extracellular chemical stimuli is medicinally an attractive approach to control disease conditions. GPCRs are the most important group of transmembranal receptors that produce different patterns of activations using intracellular mediators (such as G-proteins and Beta-arrestins). Adenosine receptors (ARs) belong to GPCR class and are divided into A1AR, A2AAR, A2BAR and A3AR. ARs control different physiological activities thus considered valuable target to control neural, heart, inflammatory and other metabolic disorders. Targeting ARs using small molecules essentially works by binding orthosteric and/or allosteric sites of the receptors. Although targeting orthosteric site is considered typical to modulate receptor activity, allosteric sites provide better subtype selectivity, saturable modulation of activity and variable activation patterns. Each receptor exists in dynamical equilibrium between conformational ensembles. The equilibrium is affected by receptor interaction with other molecules. Changing the population of conformational ensembles of the receptor is the method by which orthosteric, allosteric and other cellular components control receptor signaling. Herein, the interactions of ARs with orthosteric, allosteric ligands as well as intracellular mediators are described. A quinary interaction model for the receptor is proposed and energy wells for major conformational ensembles are retrieved.
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Affiliation(s)
| | - Mohd Nizam Mordi
- Centre For Drug Research, Universiti Sains Malaysia, 11800 Gelugor, Penang, Malaysia
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Seyedabadi M, Ghahremani MH, Albert PR. Biased signaling of G protein coupled receptors (GPCRs): Molecular determinants of GPCR/transducer selectivity and therapeutic potential. Pharmacol Ther 2019; 200:148-178. [PMID: 31075355 DOI: 10.1016/j.pharmthera.2019.05.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023]
Abstract
G protein coupled receptors (GPCRs) convey signals across membranes via interaction with G proteins. Originally, an individual GPCR was thought to signal through one G protein family, comprising cognate G proteins that mediate canonical receptor signaling. However, several deviations from canonical signaling pathways for GPCRs have been described. It is now clear that GPCRs can engage with multiple G proteins and the line between cognate and non-cognate signaling is increasingly blurred. Furthermore, GPCRs couple to non-G protein transducers, including β-arrestins or other scaffold proteins, to initiate additional signaling cascades. Receptor/transducer selectivity is dictated by agonist-induced receptor conformations as well as by collateral factors. In particular, ligands stabilize distinct receptor conformations to preferentially activate certain pathways, designated 'biased signaling'. In this regard, receptor sequence alignment and mutagenesis have helped to identify key receptor domains for receptor/transducer specificity. Furthermore, molecular structures of GPCRs bound to different ligands or transducers have provided detailed insights into mechanisms of coupling selectivity. However, receptor dimerization, compartmentalization, and trafficking, receptor-transducer-effector stoichiometry, and ligand residence and exposure times can each affect GPCR coupling. Extrinsic factors including cell type or assay conditions can also influence receptor signaling. Understanding these factors may lead to the development of improved biased ligands with the potential to enhance therapeutic benefit, while minimizing adverse effects. In this review, evidence for ligand-specific GPCR signaling toward different transducers or pathways is elaborated. Furthermore, molecular determinants of biased signaling toward these pathways and relevant examples of the potential clinical benefits and pitfalls of biased ligands are discussed.
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Affiliation(s)
- Mohammad Seyedabadi
- Department of Pharmacology, School of Medicine, Bushehr University of Medical Sciences, Iran; Education Development Center, Bushehr University of Medical Sciences, Iran
| | | | - Paul R Albert
- Ottawa Hospital Research Institute, Neuroscience, University of Ottawa, Canada.
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Leysen H, van Gastel J, Hendrickx JO, Santos-Otte P, Martin B, Maudsley S. G Protein-Coupled Receptor Systems as Crucial Regulators of DNA Damage Response Processes. Int J Mol Sci 2018; 19:E2919. [PMID: 30261591 PMCID: PMC6213947 DOI: 10.3390/ijms19102919] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/14/2018] [Accepted: 09/15/2018] [Indexed: 12/11/2022] Open
Abstract
G protein-coupled receptors (GPCRs) and their associated proteins represent one of the most diverse cellular signaling systems involved in both physiological and pathophysiological processes. Aging represents perhaps the most complex biological process in humans and involves a progressive degradation of systemic integrity and physiological resilience. This is in part mediated by age-related aberrations in energy metabolism, mitochondrial function, protein folding and sorting, inflammatory activity and genomic stability. Indeed, an increased rate of unrepaired DNA damage is considered to be one of the 'hallmarks' of aging. Over the last two decades our appreciation of the complexity of GPCR signaling systems has expanded their functional signaling repertoire. One such example of this is the incipient role of GPCRs and GPCR-interacting proteins in DNA damage and repair mechanisms. Emerging data now suggest that GPCRs could function as stress sensors for intracellular damage, e.g., oxidative stress. Given this role of GPCRs in the DNA damage response process, coupled to the effective history of drug targeting of these receptors, this suggests that one important future activity of GPCR therapeutics is the rational control of DNA damage repair systems.
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Affiliation(s)
- Hanne Leysen
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
| | - Jaana van Gastel
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
| | - Jhana O Hendrickx
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
| | - Paula Santos-Otte
- Institute of Biophysics, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| | - Bronwen Martin
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
| | - Stuart Maudsley
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium.
- Translational Neurobiology Group, Center of Molecular Neurology, VIB, 2610 Antwerp, Belgium.
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17
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Liu J, Liu Z, Corey DR. The Requirement for GW182 Scaffolding Protein Depends on Whether Argonaute Is Mediating Translation, Transcription, or Splicing. Biochemistry 2018; 57:5247-5256. [PMID: 30086238 DOI: 10.1021/acs.biochem.8b00602] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
GW182 and argonaute 2 (AGO2) are core proteins of the RNA interference complex. GW182 is a scaffolding protein that physically associates with AGO2 and bridges its interactions with other proteins. A fundamental problem in biology is how scaffolding proteins adapt or contribute to differing functional demands within cells. Here we test the necessity for human GW182 proteins (paralogs TNRC6A, TNRC6B, and TNRC6C) for several mechanisms of small duplex RNA-mediated control of gene expression, including translational silencing by miRNAs, translational silencing by siRNAs, transcriptional silencing, transcriptional activation, and splicing. We find that GW182 is required for transcriptional activation and for the activity of miRNAs but is dispensable for the regulation of splicing, transcriptional silencing, and the action of siRNAs. AGO2, by contrast, is necessary for each of these processes. Our data suggest that GW182 does not alter AGO2 to make it active. Instead, GW182 organizes protein complexes around AGO2. Sometimes this higher level of organization is necessary, and sometimes it is not. AGO2 and GW182 offer an example for how a partnership between a scaffolding protein and a functional protein can be powerful but not obligatory.
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Affiliation(s)
- Jing Liu
- Departments of Pharmacology and Biochemistry , The University of Texas Southwestern Medical Center , Dallas , Texas 75390 , United States
| | - Zhongtian Liu
- Departments of Pharmacology and Biochemistry , The University of Texas Southwestern Medical Center , Dallas , Texas 75390 , United States.,College of Animal Science and Technology , Northwest A&F University , Shaanxi , China 712100
| | - David R Corey
- Departments of Pharmacology and Biochemistry , The University of Texas Southwestern Medical Center , Dallas , Texas 75390 , United States
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18
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Berg KA, Clarke WP. Making Sense of Pharmacology: Inverse Agonism and Functional Selectivity. Int J Neuropsychopharmacol 2018; 21:962-977. [PMID: 30085126 PMCID: PMC6165953 DOI: 10.1093/ijnp/pyy071] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/04/2018] [Indexed: 12/12/2022] Open
Abstract
Constitutive receptor activity/inverse agonism and functional selectivity/biased agonism are 2 concepts in contemporary pharmacology that have major implications for the use of drugs in medicine and research as well as for the processes of new drug development. Traditional receptor theory postulated that receptors in a population are quiescent unless activated by a ligand. Within this framework ligands could act as agonists with various degrees of intrinsic efficacy, or as antagonists with zero intrinsic efficacy. We now know that receptors can be active without an activating ligand and thus display "constitutive" activity. As a result, a new class of ligand was discovered that can reduce the constitutive activity of a receptor. These ligands produce the opposite effect of an agonist and are called inverse agonists. The second topic discussed is functional selectivity, also commonly referred to as biased agonism. Traditional receptor theory also posited that intrinsic efficacy is a single drug property independent of the system in which the drug acts. However, we now know that a drug, acting at a single receptor subtype, can have multiple intrinsic efficacies that differ depending on which of the multiple responses coupled to a receptor is measured. Thus, a drug can be simultaneously an agonist, an antagonist, and an inverse agonist acting at the same receptor. This means that drugs have an additional level of selectivity (signaling selectivity or "functional selectivity") beyond the traditional receptor selectivity. Both inverse agonism and functional selectivity need to be considered when drugs are used as medicines or as research tools.
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Affiliation(s)
- Kelly A Berg
- Department of Pharmacology, University of Texas Health, San Antonio, Texas
| | - William P Clarke
- Department of Pharmacology, University of Texas Health, San Antonio, Texas,Correspondence: William P. Clarke, PhD, Department of Pharmacology, Mail Stop 7764, UT Health at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229 ()
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19
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Kim SH, Kim SH, Ryu SR, Lee P, Moon C. Inhibitory Effects of Zerumbone on MCP-1-Induced THP-1 Migration. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2018. [DOI: 10.15324/kjcls.2018.50.2.177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Sa Hyun Kim
- Department of Clinical Laboratory Science, Semyung University, Jecheon, Korea
| | - Si Hyun Kim
- Department of Clinical Laboratory Science, Semyung University, Jecheon, Korea
| | - Sung Ryul Ryu
- Department of Clinical Laboratory Science, Semyung University, Jecheon, Korea
| | - Pyeongjae Lee
- Department of Natural Medicine Resources, Semyung University, Jecheon, Korea
| | - Cheol Moon
- Department of Clinical Laboratory Science, Semyung University, Jecheon, Korea
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20
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TERUNUMA M. Diversity of structure and function of GABA B receptors: a complexity of GABA B-mediated signaling. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2018; 94:390-411. [PMID: 30541966 PMCID: PMC6374141 DOI: 10.2183/pjab.94.026] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 10/09/2018] [Indexed: 05/24/2023]
Abstract
γ-aminobutyric acid type B (GABAB) receptors are broadly expressed in the nervous system and play an important role in neuronal excitability. GABAB receptors are G protein-coupled receptors that mediate slow and prolonged inhibitory action, via activation of Gαi/o-type proteins. GABAB receptors mediate their inhibitory action through activating inwardly rectifying K+ channels, inactivating voltage-gated Ca2+ channels, and inhibiting adenylate cyclase. Functional GABAB receptors are obligate heterodimers formed by the co-assembly of R1 and R2 subunits. It is well established that GABAB receptors interact not only with G proteins and effectors but also with various proteins. This review summarizes the structure, subunit isoforms, and function of GABAB receptors, and discusses the complexity of GABAB receptors, including how receptors are localized in specific subcellular compartments, the mechanism regulating cell surface expression and mobility of the receptors, and the diversity of receptor signaling through receptor crosstalk and interacting proteins.
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Affiliation(s)
- Miho TERUNUMA
- Division of Oral Biochemistry, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
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21
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Rossi M, Taddei AR, Fasciani I, Maggio R, Giorgi F. The cell biology of the thyroid-disrupting mechanism of dichlorodiphenyltrichloroethane (DDT). J Endocrinol Invest 2018. [PMID: 28639207 DOI: 10.1007/s40618-017-0716-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Dichlorodiphenyltrichloroethane (DDT) is an organochlorine known for its pesticide properties and for its negative effects on human health. It was banned in most countries for its toxicity to the endocrine system, but due to its persistence at clinically relevant concentrations in both soil and animal tissues, DDT is still linked to several health and social problems. METHODS We have previously shown that DDT exposure is causally related to the extracellular release of vesicular organelles such as microvesicles and/or exosomes by using immunocytochemistry with gold-tagged antibodies and various fluorescent membrane markers. RESULTS It is now well recognized that microvesicles and/or exosomes organelles are implicated in cell-to-cell communication, and that they are fundamental elements for transferring proteins, RNA, DNA, lipids and transcriptional factors among cells. In this short review, we discussed the role of extracellular vesicle formation in the thyroid-disrupting mechanism of DDT. In particular, we described how DDT, by dislodging the thyrotropin hormone (TSH) receptor from the raft containing compartments of the cells, prevents its activation and internalization. CONCLUSION Based on our earlier finding and on the large body of evidence here reviewed, we propose that DDT-induced formation of extracellular vesicles containing the TSH receptor could be directly involved in the development of autoimmune responses against the TSH receptor and that, therefore, their release could lead to the development of the Graves' disease.
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Affiliation(s)
- M Rossi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA
| | - A R Taddei
- Section of Electron Microscopy, Great Equipment Center, University of Tuscia, Viterbo, Italy
| | - I Fasciani
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - R Maggio
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy.
| | - F Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
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22
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Itoh N, Nagai T, Watanabe T, Taki K, Nabeshima T, Kaibuchi K, Yamada K. Valosin-containing protein (VCP) is a novel IQ motif-containing GTPase activating protein 1 (IQGAP1)-interacting protein. Biochem Biophys Res Commun 2017; 493:1384-1389. [PMID: 28970065 DOI: 10.1016/j.bbrc.2017.09.159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 09/28/2017] [Indexed: 02/05/2023]
Abstract
Scaffold proteins play a pivotal role in making protein complexes, and organize binding partners into a functional unit to enhance specific signaling pathways. IQ motif-containing GTPase activating protein 1 (IQGAP1) is an essential protein for spine formation due to its role in scaffolding multiple signal complexes. However, it remains unclear how IQGAP1 interacts within the brain. In the present study, we screened novel IQGAP1-interacting proteins by a proteomic approach. As a novel IQGAP1-interacting protein, we identified valosin-containing protein (VCP) which is a causative gene in patients with inclusion body myopathy with Paget's disease of bone and frontotemporal dementia (IBMPFD). The physiological interaction of IQGAP1 with VCP was confirmed by an immunoprecipitation assay. Both the N-terminal (N-half) and C-terminal (C-half) fragments of IQGAP1 interacted with the N-terminal region of VCP. Co-localization of IQGAP1 and VCP was observed in the growth corn, axonal shaft, cell body, and dendrites in cultured hippocampal neurons at 4 days in vitro (DIV4). In cultured neurons at DIV14, IQGAP1 co-localized with VCP in dendrites. When HEK293T cells were co-transfected with IQGAP1 and VCP, an immunoprecipitation assay revealed that binding of IQGAP1 with disease-related mutant (R155H or A232E) VCP was markedly reduced compared to wild-type (WT) VCP. These results suggest that reduction of IQGAP1 and VCP interaction may be associated with the pathophysiology of IBMPFD.
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Affiliation(s)
- Norimichi Itoh
- Department of Neuropsychopharmacology and Hospital Pharmacy, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8560, Japan; Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Taku Nagai
- Department of Neuropsychopharmacology and Hospital Pharmacy, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8560, Japan
| | - Takashi Watanabe
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Kentaro Taki
- Division for Medical Research Engineering, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Toshitaka Nabeshima
- Advanced Diagnostic System Research Laboratory, Fujita Health University Graduate School of Health Sciences and Aino University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Kiyofumi Yamada
- Department of Neuropsychopharmacology and Hospital Pharmacy, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8560, Japan.
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23
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Chen Y, Booth C, Wang H, Wang RX, Terzi D, Zachariou V, Jiao K, Zhang J, Wang Q. Effective Attenuation of Adenosine A1R Signaling by Neurabin Requires Oligomerization of Neurabin. Mol Pharmacol 2017; 92:630-639. [PMID: 28954816 DOI: 10.1124/mol.117.109462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/25/2017] [Indexed: 12/17/2022] Open
Abstract
The adenosine A1 receptor (A1R) is a key mediator of the neuroprotective effect by endogenous adenosine. Yet targeting this receptor for neuroprotection is challenging due to its broad expression throughout the body. A mechanistic understanding of the regulation of A1R signaling is necessary for the future design of therapeutic agents that can selectively enhance A1R-mediated responses in the nervous system. In this study, we demonstrate that A1R activation leads to a sustained localization of regulator of G protein signaling 4 (RGS4) at the plasma membrane, a process that requires neurabin (a neural tissue-specific protein). A1R and RGS4 interact with the overlapping regions of neurabin. In addition, neurabin domains required for oligomerization are essential for formation of the A1R/neurabin/RGS4 ternary complex, as well as for stable localization of RGS4 at the plasma membrane and attenuation of A1R signaling. Thus, A1R and RGS4 each likely interact with one neurabin molecule in a neurabin homo-oligomer to form a ternary complex, representing a novel mode of regulation of G protein-coupled receptor signaling by scaffolding proteins. Our mechanistic analysis of neurabin-mediated regulation of A1R signaling in this study will be valuable for the future design of therapeutic agents that can selectively enhance A1R-mediated responses in the nervous system.
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Affiliation(s)
- Yunjia Chen
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Christopher Booth
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Hongxia Wang
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Raymond X Wang
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Dimitra Terzi
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Venetia Zachariou
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Kai Jiao
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Jin Zhang
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
| | - Qin Wang
- Departments of Cell, Developmental, and Integrative Biology (Y.C., H.W., R.X.W., Q.W.) and Genetics (K.J.), University of Alabama, Birmingham, Alabama; Department of Pharmacology, University of California, San Diego, California (C.B., J.Z.); and Department of Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York (D.T., V.Z.)
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24
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Zhu Y, Yang Q, Yang M, Zhan X, Lan F, He J, Gu Z, Wu Y. Protein Corona of Magnetic Hydroxyapatite Scaffold Improves Cell Proliferation via Activation of Mitogen-Activated Protein Kinase Signaling Pathway. ACS NANO 2017; 11:3690-3704. [PMID: 28314099 DOI: 10.1021/acsnano.6b08193] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The beneficial effect of magnetic scaffolds on the improvement of cell proliferation has been well documented. Nevertheless, the underlying mechanisms about the magnetic scaffolds stimulating cell proliferation remain largely unknown. Once the scaffold enters into the biological fluids, a protein corona forms and directly influences the biological function of scaffold. This study aimed at investigating the formation of protein coronas on hydroxyapatite (HA) and magnetic hydroxyapatite (MHA) scaffolds in vitro and in vivo, and consequently its effect on regulating cell proliferation. The results demonstrated that magnetic nanoparticles (MNP)-infiltrated HA scaffolds altered the composition of protein coronas and ultimately contributed to increased concentration of proteins related to calcium ions, G-protein coupled receptors (GPCRs), and MAPK/ERK cascades as compared with pristine HA scaffolds. Noticeably, the enriched functional proteins on MHA samples could efficiently activate of the MAPK/ERK signaling pathway, resulting in promoting MC3T3-E1 cell proliferation, as evidenced by the higher expression levels of the key proteins in the MAPK/ERK signaling pathway, including mitogen-activated protein kinase kinases1/2 (MEK1/2) and extracellular signal regulated kinase 1/2 (ERK1/2). Artificial down-regulation of MEK expression can significantly down-regulate the MAPK/ERK signaling and consequently suppress the cell proliferation on MHA samples. These findings not only provide a critical insight into the molecular mechanism underlying cellular proliferation on magnetic scaffolds, but also have important implications in the design of magnetic scaffolds for bone tissue engineering.
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Affiliation(s)
- Yue Zhu
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Qi Yang
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Minggang Yang
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Xiaohui Zhan
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Fang Lan
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Jing He
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Zhongwei Gu
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
| | - Yao Wu
- National Engineering Research Center for Biomaterials, Sichuan University , Chengdu, Sichuan 610064, P.R. China
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Herraiz C, Garcia-Borron JC, Jiménez-Cervantes C, Olivares C. MC1R signaling. Intracellular partners and pathophysiological implications. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2448-2461. [PMID: 28259754 DOI: 10.1016/j.bbadis.2017.02.027] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 01/11/2017] [Accepted: 02/23/2017] [Indexed: 12/12/2022]
Abstract
The melanocortin-1 receptor (MC1R) preferentially expressed in melanocytes is best known as a key regulator of the synthesis of epidermal melanin pigments. Its paracrine stimulation by keratinocyte-derived melanocortins also activates DNA repair pathways and antioxidant defenses to build a complex, multifaceted photoprotective response. Many MC1R actions rely on cAMP-dependent activation of two transcription factors, MITF and PGC1α, but pleiotropic MC1R signaling also involves activation of mitogen-activated kinases and AKT. MC1R partners such as β-arrestins, PTEN and the E3 ubiquitin ligase MGRN1 differentially regulate these pathways. The MC1R gene is complex and polymorphic, with frequent variants associated with skin phenotypes and increased cancer risk. We review current knowledge of signaling from canonical MC1R, its splice isoforms and natural polymorphic variants. Recently discovered intracellular targets and partners are also discussed, to highlight the diversity of mechanisms that may contribute to normal and pathological variation of pigmentation and sensitivity to solar radiation-induced damage. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
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Affiliation(s)
- Cecilia Herraiz
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
| | - Jose C Garcia-Borron
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain.
| | - Celia Jiménez-Cervantes
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
| | - Conchi Olivares
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
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Bartuzi D, Kaczor AA, Targowska-Duda KM, Matosiuk D. Recent Advances and Applications of Molecular Docking to G Protein-Coupled Receptors. Molecules 2017; 22:molecules22020340. [PMID: 28241450 PMCID: PMC6155844 DOI: 10.3390/molecules22020340] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 01/27/2017] [Accepted: 02/15/2017] [Indexed: 12/16/2022] Open
Abstract
The growing number of studies on G protein-coupled receptors (GPCRs) family are a source of noticeable improvement in our understanding of the functioning of these proteins. GPCRs are responsible for a vast part of signaling in vertebrates and, as such, invariably remain in the spotlight of medicinal chemistry. A deeper insight into the underlying mechanisms of interesting phenomena observed in GPCRs, such as biased signaling or allosteric modulation, can be gained with experimental and computational studies. The latter play an important role in this process, since they allow for observations on scales inaccessible for most other methods. One of the key steps in such studies is proper computational reconstruction of actual ligand-receptor or protein-protein interactions, a process called molecular docking. A number of improvements and innovative applications of this method were documented recently. In this review, we focus particularly on innovations in docking to GPCRs.
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Affiliation(s)
- Damian Bartuzi
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modelling Lab, Medical University of Lublin, 4A Chodźki Str., PL20093 Lublin, Poland.
| | - Agnieszka A Kaczor
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modelling Lab, Medical University of Lublin, 4A Chodźki Str., PL20093 Lublin, Poland.
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1, P.O. Box 1627, FI-70211 Kuopio, Finland.
| | | | - Dariusz Matosiuk
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modelling Lab, Medical University of Lublin, 4A Chodźki Str., PL20093 Lublin, Poland.
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27
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Webling K, Runesson J, Lang A, Saar I, Kofler B, Langel Ü. Ala 5-galanin (2-11) is a GAL 2R specific galanin analogue. Neuropeptides 2016; 60:75-82. [PMID: 27592409 DOI: 10.1016/j.npep.2016.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 08/11/2016] [Accepted: 08/22/2016] [Indexed: 12/18/2022]
Abstract
It is over 30years since the regulatory peptide galanin was discovered by Professor Mutt and co-workers. Galanin exerts its effects by binding to three galanin G-protein coupled receptors, namely GAL1R, GAL2R and GAL3R. Each galanin receptor has a different distribution in the central nervous system and the peripheral nervous system as well as distinctive signaling pathways, which implicates that the receptors are involved in different biological- and pathological effects. The delineation of the galaninergic system is however difficult due to a lack of stable, specific galanin receptor ligands. Herein, a new short GAL2R specific ligand, Ala5-galanin (2-11), is presented. The galanin (2-11) modified analogue Ala5-galanin (2-11) was tested in 125I-galanin competitive binding studies for the three galanin receptors and the G-protein coupled receptor signaling properties was tested by the ability to influence second-messenger molecules like inositol phosphate and cyclic adenosine monophosphate. In addition, two different label-free real-time assays, namely EnSpire® based on an optical biosensor and xCELLigence® based on an electric biosensor, were used for evaluating the signaling properties using cell lines with different levels of receptor expression. Ala5-galanin (2-11) was subsequently found to be a full agonist for GAL2R with more than 375-fold preference for GAL2R compared to both GAL1R and GAL3R. The single amino acid substitution of serine to alanine at position 5 in the short ligand galanin (2-11) resulted in a ligand subsequently unable to bind neither GAL3R nor GAL1R, even at concentrations as high as 0.1mM.
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Affiliation(s)
- Kristin Webling
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden.
| | - Johan Runesson
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden
| | - Andreas Lang
- Research Program for Receptorbiochemistry and Tumormetabolism, Laura Bassi Centre of Expertise THERAPEP, Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Müllner Hauptstr. 48, A-5020 Salzburg, Austria
| | - Indrek Saar
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Barbara Kofler
- Research Program for Receptorbiochemistry and Tumormetabolism, Laura Bassi Centre of Expertise THERAPEP, Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Müllner Hauptstr. 48, A-5020 Salzburg, Austria
| | - Ülo Langel
- Department of Neurochemistry, Stockholm University, Svante Arrheniusv. 16B, SE-10691 Stockholm, Sweden; Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
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May V, Parsons RL. G Protein-Coupled Receptor Endosomal Signaling and Regulation of Neuronal Excitability and Stress Responses: Signaling Options and Lessons From the PAC1 Receptor. J Cell Physiol 2016; 232:698-706. [DOI: 10.1002/jcp.25615] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 09/22/2016] [Indexed: 02/03/2023]
Affiliation(s)
- Victor May
- Department of Neurological Sciences; University of Vermont College of Medicine; Burlington Vermont
| | - Rodney L. Parsons
- Department of Neurological Sciences; University of Vermont College of Medicine; Burlington Vermont
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Kleinau G, Müller A, Biebermann H. Oligomerization of GPCRs involved in endocrine regulation. J Mol Endocrinol 2016; 57:R59-80. [PMID: 27151573 DOI: 10.1530/jme-16-0049] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 05/04/2016] [Indexed: 12/27/2022]
Abstract
More than 800 different human membrane-spanning G-protein-coupled receptors (GPCRs) serve as signal transducers at biological barriers. These receptors are activated by a wide variety of ligands such as peptides, ions and hormones, and are able to activate a diverse set of intracellular signaling pathways. GPCRs are of central importance in endocrine regulation, which underpins the significance of comprehensively studying these receptors and interrelated systems. During the last decade, the capacity for multimerization of GPCRs was found to be a common and functionally relevant property. The interaction between GPCR monomers results in higher order complexes such as homomers (identical receptor subtype) or heteromers (different receptor subtypes), which may be present in a specific and dynamic monomer/oligomer equilibrium. It is widely accepted that the oligomerization of GPCRs is a mechanism for determining the fine-tuning and expansion of cellular processes by modification of ligand action, expression levels, and related signaling outcome. Accordingly, oligomerization provides exciting opportunities to optimize pharmacological treatment with respect to receptor target and tissue selectivity or for the development of diagnostic tools. On the other hand, GPCR heteromerization may be a potential reason for the undesired side effects of pharmacological interventions, faced with numerous and common mutual signaling modifications in heteromeric constellations. Finally, detailed deciphering of the physiological occurrence and relevance of specific GPCR/GPCR-ligand interactions poses a future challenge. This review will tackle the aspects of GPCR oligomerization with specific emphasis on family A GPCRs involved in endocrine regulation, whereby only a subset of these receptors will be discussed in detail.
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Affiliation(s)
- Gunnar Kleinau
- Institute of Experimental Pediatric Endocrinology (IEPE)Charité-Universitätsmedizin, Berlin, Germany
| | - Anne Müller
- Institute of Experimental Pediatric Endocrinology (IEPE)Charité-Universitätsmedizin, Berlin, Germany
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology (IEPE)Charité-Universitätsmedizin, Berlin, Germany
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30
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Cai Z, Chai Y, Zhang C, Feng R, Sang H, Lu L. Molecular Characterization of Gβ-Like Protein CpcB Involved in Antifungal Drug Susceptibility and Virulence in A. fumigatus. Front Microbiol 2016; 7:106. [PMID: 26903985 PMCID: PMC4746314 DOI: 10.3389/fmicb.2016.00106] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 01/20/2016] [Indexed: 12/16/2022] Open
Abstract
Aspergillus fumigatus is an airborne human fungal pathogen that can survive in a wide range of environmental condition. G protein complex transduces external signals from a variety of stimuli outside a cell to its interior effectors in all eukaryotes. Gβ-like CpcB (cross pathway control B) belongs to a WD40 repeat protein family with the conserved G-H and W-D residues. Previous studies have demonstrated that Gβ-like proteins cooperate with related signal transduction proteins to function during many important developmental processes in A. fumigatus. However, the molecular characteristics of Gβ-like CpcB have not yet been identified. In this study, we demonstrated that the G-H residues in WD repeat 1, 2, 3, and the W-D residue in WD repeat 2 of CpcB are required not only to control normal hyphal growth and conidiation but also to affect antifungal drug susceptibility. The enhanced drug resistance might be due to reduced intracellular drug accumulation and altered ergosterol component. Moreover, we find that the first G-H residue of CpcB plays an important role in the virulence of A. fumigatus. To our knowledge, this is the first report for finding the importance of the conserved G-H and W-D residues for a Gβ-like protein in understanding of G protein functions.
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Affiliation(s)
- Zhendong Cai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal UniversityNanjing, China
| | - Yanfei Chai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal UniversityNanjing, China
| | - Caiyun Zhang
- Department of Dermatology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, China
| | - Ruoyun Feng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal UniversityNanjing, China
| | - Hong Sang
- Department of Dermatology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal UniversityNanjing, China
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Constantin B. Role of Scaffolding Proteins in the Regulation of TRPC-Dependent Calcium Entry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:379-403. [PMID: 27161237 DOI: 10.1007/978-3-319-26974-0_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Plasma membrane ion channels, and in particular TRPC channels need a specific membrane environment and association with scaffolding, signaling, and cytoskeleton proteins in order to play their important functional role. The molecular composition of TRPC channels is an important factor in determining channel activation mechanisms. TRPC proteins are incorporated in macromolecular complexes including several key Ca(2 +) signaling proteins as well as proteins involved in vesicle trafficking, cytoskeletal interactions, and scaffolding. Evidence has been provided for association of TRPC with calmodulin (CaM), IP3R, PMCA, Gq/11, RhoA, and a variety of scaffolding proteins. The interaction between TRPC channels with adaptor proteins, determines their mode of regulation as well as their cellular localization and function. Adaptor proteins do not display any enzymatic activity but act as scaffold for the building of signaling complexes. The scaffolding proteins are involved in the assembling of these Ca(2+) signaling complexes, the correct sub-cellular localization of protein partners, and the regulation of the TRPC channelosome. In particular, these proteins, via their multiple protein-protein interaction motifs, can interact with various ion channels involved in the transmembrane potential, and membrane excitability. Scaffolding proteins are key components for the functional organization of TRPC channelosomes that serves as a platform regulating slow Ca(2+) entry, spatially and temporally controlled [Ca(2+)]i signals and Ca(2+) -dependent cellular functions.
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Affiliation(s)
- Bruno Constantin
- Laboratory STIM, ERL-7368 CNRS-Université de Poitiers, 1, rue Georges Bonnet, Bat. B36, Pôle Biologie-Santé, 86000, Poitiers, France.
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Luttrell LM, Maudsley S, Bohn LM. Fulfilling the Promise of "Biased" G Protein-Coupled Receptor Agonism. Mol Pharmacol 2015; 88:579-88. [PMID: 26134495 DOI: 10.1124/mol.115.099630] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/01/2015] [Indexed: 12/13/2022] Open
Abstract
The fact that over 30% of current pharmaceuticals target heptahelical G protein-coupled receptors (GPCRs) attests to their tractability as drug targets. Although GPCR drug development has traditionally focused on conventional agonists and antagonists, the growing appreciation that GPCRs mediate physiologically relevant effects via both G protein and non-G protein effectors has prompted the search for ligands that can "bias" downstream signaling in favor of one or the other process. Biased ligands are novel entities with distinct signaling profiles dictated by ligand structure, and the potential prospect of biased ligands as better drugs has been pleonastically proclaimed. Indeed, preclinical proof-of-concept studies have demonstrated that both G protein and arrestin pathway-selective ligands can promote beneficial effects in vivo while simultaneously antagonizing deleterious ones. But along with opportunity comes added complexity and new challenges for drug discovery. If ligands can be biased, then ligand classification becomes assay dependent, and more nuanced screening approaches are needed to capture ligand efficacy across several dimensions of signaling. Moreover, because the signaling repertoire of biased ligands differs from that of the native agonist, unpredicted responses may arise in vivo as these unbalanced signals propagate. For any given GPCR target, establishing a framework relating in vitro efficacy to in vivo biologic response is crucial to biased drug discovery. This review discusses approaches to describing ligand efficacy in vitro, translating ligand bias into biologic response, and developing a systems-level understanding of biased agonism in vivo, with the overall goal of overcoming current barriers to developing biased GPCR therapeutics.
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Affiliation(s)
- Louis M Luttrell
- Departments of Medicine and Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, South Carolina (L.M.L.); Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina (L.M.L.); Translational Neurobiology Group, VIB Department of Molecular Genetics, Laboratory of Neurogenetics-Institute Born-Bunge, University of Antwerp, Belgium (S.M.); and Department of Molecular Therapeutics and Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida (L.M.B.)
| | - Stuart Maudsley
- Departments of Medicine and Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, South Carolina (L.M.L.); Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina (L.M.L.); Translational Neurobiology Group, VIB Department of Molecular Genetics, Laboratory of Neurogenetics-Institute Born-Bunge, University of Antwerp, Belgium (S.M.); and Department of Molecular Therapeutics and Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida (L.M.B.)
| | - Laura M Bohn
- Departments of Medicine and Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, South Carolina (L.M.L.); Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina (L.M.L.); Translational Neurobiology Group, VIB Department of Molecular Genetics, Laboratory of Neurogenetics-Institute Born-Bunge, University of Antwerp, Belgium (S.M.); and Department of Molecular Therapeutics and Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida (L.M.B.)
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