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Pedroni L, Perugino F, Magnaghi F, Dall’Asta C, Galaverna G, Dellafiora L. Free fatty acid receptors beyond fatty acids: A computational journey to explore peptides as possible binders of GPR120. Curr Res Food Sci 2024; 8:100710. [PMID: 38496766 PMCID: PMC10940776 DOI: 10.1016/j.crfs.2024.100710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/07/2024] [Accepted: 03/01/2024] [Indexed: 03/19/2024] Open
Abstract
Free fatty acids receptors, with members among G protein-coupled receptors (GPCRs), are crucial for biological signaling, including the perception of the so called "fatty taste". In recent years, GPR120, a protein belonging to the GPCR family, drew attention as an interesting pharmacological target to cope with obesity, satiety and diabetes. Apart from long chain fatty acids, which are GPR120 natural agonists, other synthetic molecules were identified as agonists expanding the chemical space of GPR120's ligands. In this scenario, we unveiled peptides as possible GPR120 binders toward a better understanding of this multifaceted and relevant target. This study analyzed a virtual library collecting 531 441 low-polar hexapeptides, providing mechanistic insights on the GPR120 activation and further extending the possible chemical space of GPR120 agonists. The computational pipeline started with a narrow filtering of hexapeptides based on their chemical similarity with known GPR120 agonists. The best hits were tested through docking studies, molecular dynamics and umbrella sampling simulations, which pointed to G[I,L]FGGG as a promising GPR120 agonist sequence. The presence of both peptides in food-related proteins was thoroughly assessed, revealing they may occur in mushrooms, food-grade bacteria and rice. Simulations on the counterparts with D-amino acids were also performed. Umbrella sampling simulations described that GdIFGGG may have a better interaction compared to its all-L counterpart (-13 kCal/mol ΔG and -6 kCal/mol ΔG, respectively). Overall, we obtained a predictive model to better understand the underpinning mechanism of GPR120-hexapeptides interaction, hierarchizing novel potential agonist peptides for further analysis and describing promising food sources worth of further dedicated investigations.
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Affiliation(s)
- Lorenzo Pedroni
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Florinda Perugino
- Department of Food and Drug, University of Parma, Parma, Italy
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Fabio Magnaghi
- Department of Food and Drug, University of Parma, Parma, Italy
| | | | | | - Luca Dellafiora
- Department of Food and Drug, University of Parma, Parma, Italy
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2
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Berna-Erro A, Granados MP, Teruel-Montoya R, Ferrer-Marin F, Delgado E, Corbacho AJ, Fenández E, Vazquez-Godoy MT, Tapia JA, Redondo PC. SARAF overexpression impairs thrombin-induced Ca 2+ homeostasis in neonatal platelets. Br J Haematol 2024; 204:988-1004. [PMID: 38062782 DOI: 10.1111/bjh.19210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 11/01/2023] [Accepted: 11/07/2023] [Indexed: 03/14/2024]
Abstract
Neonatal platelets present a reduced response to the platelet agonist, thrombin (Thr), thus resulting in a deficient Thr-induced aggregation. These alterations are more pronounced in premature newborns. Here, our aim was to uncover the causes underneath the impaired Ca2+ homeostasis described in neonatal platelets. Both Ca2+ mobilization and Ca2+ influx in response to Thr are decreased in neonatal platelets compared to maternal and control woman platelets. In neonatal platelets, we observed impaired Ca2+ mobilization in response to the PAR-1 agonist (SFLLRN) or by blocking SERCA3 function with tert-butylhydroquinone. Regarding SOCE, the STIM1 regulatory protein, SARAF, was found overexpressed in neonatal platelets, promoting an increase in STIM1/SARAF interaction even under resting conditions. Additionally, higher interaction between SARAF and PDCD61/ALG2 was also observed, reducing SARAF ubiquitination and prolonging its half-life. These results were reproduced by overexpressing SARAF in MEG01 and DAMI cells. Finally, we also observed that pannexin 1 permeability is enhanced in response to Thr in control woman and maternal platelets, but not in neonatal platelets, hence, leading to the deregulation of the Ca2+ entry found in neonatal platelets. Summarizing, we show that in neonatal platelets both Ca2+ accumulation in the intracellular stores and Thr-evoked Ca2+ entry through either capacitative channels or non-selective channels are altered in neonatal platelets, contributing to deregulated Ca2+ homeostasis in neonatal platelets and leading to the altered aggregation observed in these subjects.
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Affiliation(s)
- Alejandro Berna-Erro
- Department of Physiology (PHYCELL Group), University of Extremadura, Caceres, Spain
| | - Maria P Granados
- Pharmacy Unit of Health Center, Extremadura County Health Service, Caceres, Spain
| | - Raul Teruel-Montoya
- Hemodonation County Center, University Hospital of Morales-Meseguer, IMIB-Arrixaca, CIBERER CB55, Murcia, Spain
| | - Francisca Ferrer-Marin
- Hemodonation County Center, University Hospital of Morales-Meseguer, IMIB-Arrixaca, CIBERER CB55, Murcia, Spain
| | - Elena Delgado
- Blood Donation Center, Extremadura County Health Service, Merida, Spain
| | | | | | | | - Jose A Tapia
- Department of Physiology (PHYCELL Group), University of Extremadura, Caceres, Spain
| | - Pedro Cosme Redondo
- Department of Physiology (PHYCELL Group), University of Extremadura, Caceres, Spain
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3
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Renna SA, McKenzie SE, Michael JV. Species Differences in Platelet Protease-Activated Receptors. Int J Mol Sci 2023; 24:ijms24098298. [PMID: 37176005 PMCID: PMC10179473 DOI: 10.3390/ijms24098298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/21/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023] Open
Abstract
Protease-activated receptors (PARs) are a class of integral membrane proteins that are cleaved by a variety of proteases, most notably thrombin, to reveal a tethered ligand and promote activation. PARs are critical mediators of platelet function in hemostasis and thrombosis, and therefore are attractive targets for anti-platelet therapies. Animal models studying platelet PAR physiology have relied heavily on genetically modified mouse strains, which have provided ample insight but have some inherent limitations. The current review aims to summarize the notable PAR expression and functional differences between the mouse and human, in addition to highlighting some recently developed tools to further study human physiology in mouse models.
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Affiliation(s)
- Stephanie A Renna
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Steven E McKenzie
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - James V Michael
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
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4
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Shpakov AO. Allosteric Regulation of G-Protein-Coupled Receptors: From Diversity of Molecular Mechanisms to Multiple Allosteric Sites and Their Ligands. Int J Mol Sci 2023; 24:6187. [PMID: 37047169 PMCID: PMC10094638 DOI: 10.3390/ijms24076187] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/21/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
Allosteric regulation is critical for the functioning of G protein-coupled receptors (GPCRs) and their signaling pathways. Endogenous allosteric regulators of GPCRs are simple ions, various biomolecules, and protein components of GPCR signaling (G proteins and β-arrestins). The stability and functional activity of GPCR complexes is also due to multicenter allosteric interactions between protomers. The complexity of allosteric effects caused by numerous regulators differing in structure, availability, and mechanisms of action predetermines the multiplicity and different topology of allosteric sites in GPCRs. These sites can be localized in extracellular loops; inside the transmembrane tunnel and in its upper and lower vestibules; in cytoplasmic loops; and on the outer, membrane-contacting surface of the transmembrane domain. They are involved in the regulation of basal and orthosteric agonist-stimulated receptor activity, biased agonism, GPCR-complex formation, and endocytosis. They are targets for a large number of synthetic allosteric regulators and modulators, including those constructed using molecular docking. The review is devoted to the principles and mechanisms of GPCRs allosteric regulation, the multiplicity of allosteric sites and their topology, and the endogenous and synthetic allosteric regulators, including autoantibodies and pepducins. The allosteric regulation of chemokine receptors, proteinase-activated receptors, thyroid-stimulating and luteinizing hormone receptors, and beta-adrenergic receptors are described in more detail.
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Affiliation(s)
- Alexander O Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
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5
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Chandrabalan A, Firth A, Litchfield RB, Appleton CT, Getgood A, Ramachandran R. Human osteoarthritis knee joint synovial fluids cleave and activate Proteinase-Activated Receptor (PAR) mediated signaling. Sci Rep 2023; 13:1124. [PMID: 36670151 PMCID: PMC9859807 DOI: 10.1038/s41598-023-28068-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/12/2023] [Indexed: 01/22/2023] Open
Abstract
Osteoarthritis (OA) is the most prevalent joint disorder with increasing worldwide incidence. Mechanistic insights into OA pathophysiology are evolving and there are currently no disease-modifying OA drugs. An increase in protease activity is linked to progressive degradation of the cartilage in OA. Proteases also trigger inflammation through a family of G protein-coupled receptors (GPCRs) called the Proteinase-Activated Receptors (PARs). PAR signaling can trigger pro-inflammatory responses and targeting PARs is proposed as a therapeutic approach in OA. Several enzymes can cleave the PAR N-terminus, but the endogenous protease activators of PARs in OA remain unclear. Here we characterized PAR activating enzymes in knee joint synovial fluids from OA patients and healthy donors using genetically encoded PAR biosensor expressing cells. Calcium signaling assays were performed to examine receptor activation. The class and type of enzymes cleaving the PARs was further characterized using protease inhibitors and fluorogenic substrates. We find that PAR1, PAR2 and PAR4 activating enzymes are present in knee joint synovial fluids from healthy controls and OA patients. Compared to healthy controls, PAR1 activating enzymes are elevated in OA synovial fluids while PAR4 activating enzyme levels are decreased. Using enzyme class and type selective inhibitors and fluorogenic substrates we find that multiple PAR activating enzymes are present in OA joint fluids and identify serine proteinases (thrombin and trypsin-like) and matrix metalloproteinases as the major classes of PAR activating enzymes in the OA synovial fluids. Synovial fluid driven increase in calcium signaling was significantly reduced in cells treated with PAR1 and PAR2 antagonists, but not in PAR4 antagonist treated cells. OA associated elevation of PAR1 cleavage suggests that targeting this receptor may be beneficial in the treatment of OA.
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Affiliation(s)
- Arundhasa Chandrabalan
- Department of Physiology and Pharmacology, Bone and Joint Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, N6A 5C1, Canada
| | - Andrew Firth
- Division of Orthopedic Surgery, Bone and Joint Institute, Fowler Kennedy Sport Medicine Clinic, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Robert B Litchfield
- Division of Orthopedic Surgery, Bone and Joint Institute, Fowler Kennedy Sport Medicine Clinic, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - C Thomas Appleton
- Department of Physiology and Pharmacology, Bone and Joint Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, N6A 5C1, Canada.,Department of Medicine, Bone and Joint Institute, Schulich School of Medicine and Dentistry, The Dr. Sandy Kirkley Centre for Musculoskeletal Research, London, ON, Canada
| | - Alan Getgood
- Division of Orthopedic Surgery, Bone and Joint Institute, Fowler Kennedy Sport Medicine Clinic, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, Bone and Joint Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, N6A 5C1, Canada.
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6
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Peach CJ, Edgington-Mitchell LE, Bunnett NW, Schmidt BL. Protease-activated receptors in health and disease. Physiol Rev 2023; 103:717-785. [PMID: 35901239 PMCID: PMC9662810 DOI: 10.1152/physrev.00044.2021] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 07/08/2022] [Accepted: 07/10/2022] [Indexed: 11/22/2022] Open
Abstract
Proteases are signaling molecules that specifically control cellular functions by cleaving protease-activated receptors (PARs). The four known PARs are members of the large family of G protein-coupled receptors. These transmembrane receptors control most physiological and pathological processes and are the target of a large proportion of therapeutic drugs. Signaling proteases include enzymes from the circulation; from immune, inflammatory epithelial, and cancer cells; as well as from commensal and pathogenic bacteria. Advances in our understanding of the structure and function of PARs provide insights into how diverse proteases activate these receptors to regulate physiological and pathological processes in most tissues and organ systems. The realization that proteases and PARs are key mediators of disease, coupled with advances in understanding the atomic level structure of PARs and their mechanisms of signaling in subcellular microdomains, has spurred the development of antagonists, some of which have advanced to the clinic. Herein we review the discovery, structure, and function of this receptor system, highlight the contribution of PARs to homeostatic control, and discuss the potential of PAR antagonists for the treatment of major diseases.
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Affiliation(s)
- Chloe J Peach
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York
- Department of Neuroscience and Physiology and Neuroscience Institute, Grossman School of Medicine, New York University, New York, New York
| | - Laura E Edgington-Mitchell
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
- Bluestone Center for Clinical Research, Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, New York, New York
| | - Nigel W Bunnett
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York
- Department of Neuroscience and Physiology and Neuroscience Institute, Grossman School of Medicine, New York University, New York, New York
| | - Brian L Schmidt
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York
- Bluestone Center for Clinical Research, Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, New York, New York
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7
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Fang H, Yuan Z, Zhu Y, Tang H, Pang C, Li J, Shi J, Guo W, Zhang S. Blocking protease-activated receptor 4 alleviates liver injury induced by brain death. Biochem Biophys Res Commun 2022; 595:47-53. [PMID: 35093640 DOI: 10.1016/j.bbrc.2022.01.074] [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: 11/25/2021] [Accepted: 01/19/2022] [Indexed: 11/29/2022]
Abstract
Brain death (BD) induces a systemic inflammatory response that influences donor liver quality. Protease-activated receptor 4 (PAR4) is a thrombin receptor that mediates platelet activation and is involved in inflammatory and apoptotic processes. Therefore, we investigated the role of PAR4 blockade in liver injury induced by BD and its associated mechanisms. In this study, we constructed a BD rat model and treated rats with TcY-NH2, a selective PAR4 antagonist, to block PAR4 signaling at the onset of BD induction. Our results revealed that PAR4 protein expression increased in the livers of rats with BD. PAR4 blockade alleviated liver injury induced by BD, as indicated by lower serum ALT/AST levels and an improvement in histomorphology. Blood platelet activation and hepatic platelet accumulation in BD rats were reduced by PAR4 blockade. Additionally, PAR4 blockade attenuated the inflammatory response and apoptosis in the livers of BD rats. Moreover, the activation of NF-κB and MAPK pathways induced by BD was inhibited by PAR4 blockade. Thus, our results suggest that PAR4 contributes to liver injury induced by BD by regulating inflammation and apoptosis through the NF-κB and MAPK pathways. Thus, PAR4 blockade may provide a feasible approach to improve the quality of organs from BD donors.
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Affiliation(s)
- Hongbo Fang
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China
| | - Zibo Yuan
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China
| | - Yaohua Zhu
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China
| | - Hongwei Tang
- Henan Key Laboratory for Digestive Organ Transplantation, Zhengzhou City, Henan Province, China; Zhengzhou Key Laboratory for Hepatobiliary & Pancreatic Diseases and Organ Transplantation, Zhengzhou City, Henan Province, China
| | - Chun Pang
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China
| | - Jie Li
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China
| | - Jihua Shi
- Henan Key Laboratory for Digestive Organ Transplantation, Zhengzhou City, Henan Province, China; Zhengzhou Key Laboratory for Hepatobiliary & Pancreatic Diseases and Organ Transplantation, Zhengzhou City, Henan Province, China
| | - Wenzhi Guo
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China; Henan Key Laboratory for Digestive Organ Transplantation, Zhengzhou City, Henan Province, China; Zhengzhou Key Laboratory for Hepatobiliary & Pancreatic Diseases and Organ Transplantation, Zhengzhou City, Henan Province, China
| | - Shuijun Zhang
- Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China; Henan Key Laboratory for Digestive Organ Transplantation, Zhengzhou City, Henan Province, China; Zhengzhou Key Laboratory for Hepatobiliary & Pancreatic Diseases and Organ Transplantation, Zhengzhou City, Henan Province, China.
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8
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Zhao JF, Ren T, Li XY, Guo TL, Liu CH, Wang X. Research Progress on the Role of Microglia Membrane Proteins or Receptors in Neuroinflammation and Degeneration. Front Cell Neurosci 2022; 16:831977. [PMID: 35281298 PMCID: PMC8913711 DOI: 10.3389/fncel.2022.831977] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/26/2022] [Indexed: 01/01/2023] Open
Abstract
Microglia are intrinsic immune cells of the central nervous system and play a dual role (pro-inflammatory and anti-inflammatory) in the homeostasis of the nervous system. Neuroinflammation mediated by microglia serves as an important stage of ischemic hypoxic brain injury, cerebral hemorrhage disease, neurodegeneration and neurotumor of the nervous system and is present through the whole course of these diseases. Microglial membrane protein or receptor is the basis of mediating microglia to play the inflammatory role and they have been found to be upregulated by recognizing associated ligands or sensing changes in the nervous system microenvironment. They can then allosterically activate the downstream signal transduction and produce a series of complex cascade reactions that can activate microglia, promote microglia chemotactic migration and stimulate the release of proinflammatory factor such as TNF-α, IL-β to effectively damage the nervous system and cause apoptosis of neurons. In this paper, several representative membrane proteins or receptors present on the surface of microglia are systematically reviewed and information about their structures, functions and specific roles in one or more neurological diseases. And on this basis, some prospects for the treatment of novel coronavirus neurological complications are presented.
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Affiliation(s)
- Jun-Feng Zhao
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Tong Ren
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Xiang-Yu Li
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Tian-Lin Guo
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Chun-Hui Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Beijing, China
- Chun-Hui Liu,
| | - Xun Wang
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
- *Correspondence: Xun Wang,
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9
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Cao D, Strainic MG, Counihan D, Sridar S, An F, Hussain W, Schmaier AH, Nieman M, Medof ME. Vascular Endothelial Cells Produce Coagulation Factors That Control Their Growth via Joint Protease-Activated Receptor and C5a Receptor 1 (CD88) Signaling. THE AMERICAN JOURNAL OF PATHOLOGY 2022; 192:361-378. [PMID: 35144762 PMCID: PMC8908053 DOI: 10.1016/j.ajpath.2021.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/20/2021] [Accepted: 09/29/2021] [Indexed: 02/03/2023]
Abstract
As per the classical view of the coagulation system, it functions solely in plasma to maintain hemostasis. An experimental approach modeling vascular reconstitution was used to show that vascular endothelial cells (ECs) endogenously synthesize coagulation factors during angiogenesis. Intracellular thrombin generated from this synthesis promotes the mitotic function of vascular endothelial cell growth factor A (VEGF-A). The thrombin concurrently cleaves C5a from EC-synthesized complement component C5 and unmasks the tethered ligand for EC-expressed protease-activated receptor 4 (PAR4). The two ligands jointly trigger EC C5a receptor-1 (C5ar1) and PAR4 signaling, which together promote VEGF receptor 2 growth signaling. C5ar1 is functionally associated with PAR4, enabling C5a or thrombin to elicit Gαi and/or Gαq signaling. EC coagulation factor and EC complement component synthesis concurrently down-regulate with contact inhibition. The connection of these processes with VEGF receptor 2 signaling provides new insights into mechanisms underlying angiogenesis. Knowledge of endogenous coagulation factor/complement component synthesis and joint PAR4/C5ar1 signaling could be applied to other cell types.
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Affiliation(s)
- Devin Cao
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio
| | | | - Daniel Counihan
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio
| | - Shiva Sridar
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio
| | - Fengqi An
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio
| | - Wasim Hussain
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio
| | - Alvin H. Schmaier
- Department of Medicine, University Hospitals Cleveland Medical Center, Cleveland, Ohio
| | - Marvin Nieman
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - M. Edward Medof
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio,Address correspondence to M. Edward Medof, M.D., Ph.D., Institute of Pathology, 2085 Adelbert, Room 301, Cleveland, OH 44106.
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10
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Kuriri F, Burchall G, Alanazi F, Antonipillai J, Dobie G, Beauchemin N, Jackson DE. Mice lacking PECAM-1 and Ceacam1 have an aberrant platelet and thrombus phenotype. Thromb Haemost 2021; 122:961-973. [PMID: 34619794 DOI: 10.1055/a-1663-8108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The immunoglobulin (Ig)-immunoreceptor tyrosine-based inhibitory motif (ITIM) bearing receptors, PECAM-1 and CEACAM1 have been shown net negative regulators of platelet-collagen interactions and hemi-ITAM signalling pathways. In this study, a double knockout (DKO) mouse was developed with deleted PECAM-1 and CEACAM1 to study their combined contribution in platelet activation by glycoprotein VI, C-type lectin-like receptor 2 (CLEC-2), protease activated receptor PAR-4, ADP purinergic receptors and thromboxane receptor TP A2 pathways. Additionally, their collective contribution was examined in thrombus formation under high shear and microvascular thrombosis using in vivo models. DKO platelets responded normally to ADP purinergic receptors and TP A2 pathway. However, DKO platelets released significantly higher amounts of P-selectin compared to hyper-responsive Pecam-1-/- or Ceacam1-/- versus wild-type (WT) upon stimulation with collagen related peptide or rhodocytin. Contrastingly, DKO platelets released increased amounts of P-selectin upon stimulation with PAR-4 agonist peptide or thrombin but not Pecam-1-/-, Ceacam1-/- or WT platelets. Blockade of phospholipase C (PLC) or Rho A kinase revealed that DKO platelets enhanced alpha granule release via PAR-4/Gαq/PLC signalling without crosstalk with Src/Syk or G12/13 signalling pathways. This DKO model showed a significant increase in thrombus formation compared to the hyper-responsive Ceacam1-/- or Pecam-1-/- versus WT phenotype. DKO platelets have similar glycoprotein surface expression compared to Pecam-1-/-, Ceacam1-/- and WT platelets. PECAM-1 and CEACAM1 work in concert to negatively regulate hemiITAM signalling, platelet-collagen interactions and PAR-4 Gαq protein coupled signalling pathways. Both PECAM-1 and CEACAM1 are required for negative regulation of platelet activation and microvascular thrombosis in vivo.
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Affiliation(s)
- Fahd Kuriri
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia.,Shaqra University College of Applied Medical Sciences, Shaqra, Saudi Arabia
| | | | - Fehaid Alanazi
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia.,College of Applied Medical Sciences, Al Jouf University, Skaka, Saudi Arabia
| | - Juliana Antonipillai
- Thrombosis and Vascular Diseases Laboratory, RMIT University, Melbourne, Australia
| | - Gasim Dobie
- Haematology Unit, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
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11
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Huang J, Byun JA, VanSchouwen B, Henning P, Herberg FW, Kim C, Melacini G. Dynamical Basis of Allosteric Activation for the Plasmodium falciparum Protein Kinase G. J Phys Chem B 2021; 125:6532-6542. [PMID: 34115498 DOI: 10.1021/acs.jpcb.1c03622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Plasmodium falciparum cGMP-dependent protein kinase (PfPKG) is required for the progression of the Plasmodium's life cycle and is therefore a promising malaria drug target. PfPKG includes four cGMP-binding domains (CBD-A to CBD-D). CBD-D plays a crucial role in PfPKG regulation as it is the primary determinant for the inhibition and cGMP-dependent activation of the catalytic domain. Hence, it is critical to understand how CBD-D is allosterically regulated by cGMP. Although the apo versus holo conformational changes of CBD-D have been reported, information on the intermediates of the activation pathway is currently lacking. Here, we employed molecular dynamics simulations to model four key states along the thermodynamic cycle for the cGMP-dependent activation of the PfPKG CBD-D domain. The simulations were compared to NMR data, and they revealed that the PfPKG CBD-D activation pathway samples a compact intermediate in which the N- and C-terminal helices approach the central β-barrel. In addition, by comparing the cGMP-bound active and inactive states, the essential binding interactions that differentiate these states were identified. The identification of structural and dynamical features unique to the cGMP-bound inactive state provides a promising basis to design PfPKG-selective allosteric inhibitors as a viable treatment for malaria.
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Affiliation(s)
- Jinfeng Huang
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Jung Ah Byun
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Bryan VanSchouwen
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Philipp Henning
- Department of Biochemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132 Kassel, Germany
| | - Friedrich W Herberg
- Department of Biochemistry, University of Kassel, Heinrich-Plett-Strasse 40, 34132 Kassel, Germany
| | - Choel Kim
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, United States.,Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States.,Center for Drug Discovery, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Giuseppe Melacini
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada.,Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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12
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Chandrabalan A, Ramachandran R. Molecular mechanisms regulating Proteinase‐Activated Receptors (PARs). FEBS J 2021; 288:2697-2726. [DOI: 10.1111/febs.15829] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/10/2021] [Accepted: 03/18/2021] [Indexed: 12/13/2022]
Affiliation(s)
- Arundhasa Chandrabalan
- Department of Physiology and Pharmacology Schulich School of Medicine and Dentistry University of Western Ontario London Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology Schulich School of Medicine and Dentistry University of Western Ontario London Canada
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13
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Molecular Dambusters: What Is Behind Hyperpermeability in Bradykinin-Mediated Angioedema? Clin Rev Allergy Immunol 2021; 60:318-347. [PMID: 33725263 PMCID: PMC7962090 DOI: 10.1007/s12016-021-08851-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2021] [Indexed: 02/08/2023]
Abstract
In the last few decades, a substantial body of evidence underlined the pivotal role of bradykinin in certain types of angioedema. The formation and breakdown of bradykinin has been studied thoroughly; however, numerous questions remained open regarding the triggering, course, and termination of angioedema attacks. Recently, it became clear that vascular endothelial cells have an integrative role in the regulation of vessel permeability. Apart from bradykinin, a great number of factors of different origin, structure, and mechanism of action are capable of modifying the integrity of vascular endothelium, and thus, may participate in the regulation of angioedema formation. Our aim in this review is to describe the most important permeability factors and the molecular mechanisms how they act on endothelial cells. Based on endothelial cell function, we also attempt to explain some of the challenging findings regarding bradykinin-mediated angioedema, where the function of bradykinin itself cannot account for the pathophysiology. By deciphering the complex scenario of vascular permeability regulation and edema formation, we may gain better scientific tools to be able to predict and treat not only bradykinin-mediated but other types of angioedema as well.
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14
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Han X, Nieman MT, Kerlin BA. Protease-activated receptors: An illustrated review. Res Pract Thromb Haemost 2020; 5:17-26. [PMID: 33537526 PMCID: PMC7845062 DOI: 10.1002/rth2.12454] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/30/2020] [Accepted: 10/12/2020] [Indexed: 01/04/2023] Open
Abstract
Proteases are important regulators of cell behavior, survival, and apoptosis. They communicate to cells directly through a special class of G‐protein–coupled receptors known as protease‐activated receptors (PARs). N‐terminal PAR proteolysis unmasks a neo‐N‐terminus, which serves as a tethered ligand to activate PARs. Using this unique irreversible activation mechanism, PARs relay information across cell membranes. The year 2020 is the 30th year since discovery of the first member of this family, PAR1. In this illustrated review, we highlight achievements in the PAR field over the past 3 decades. Additionally, the known expression profiles of PARs in human tissues and across species are portrayed. We also illustrate the tethered ligand activation mechanism, which is unique to PARs, and PAR regulatory mechanisms. PAR1 was originally named “thrombin receptor” because thrombin was the first protease identified to activate PAR1. However, over the past 30 years, a growing number of proteases have been found to cleave PARs and trigger differential downstream signaling depending on cleavage site, cell type, and species. We exemplify the diversity of PAR1‐mediated signaling outcomes in platelets and endothelial cells as pertinent examples to the hemostasis, thrombosis, and vascular biology fields. Further, the termination and regulation of PAR signaling via endocytosis and currently available pharmacologic approaches are depicted. We conclude with portrayal of clinically translational aspects of PAR biology including pharmacologic manipulation and single‐nucleotide polymorphisms.
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Affiliation(s)
- Xu Han
- Department of Pharmacology Case Western Reserve University Cleveland OH USA
| | - Marvin T Nieman
- Department of Pharmacology Case Western Reserve University Cleveland OH USA
| | - Bryce A Kerlin
- Center for Clinical and Translational Research Abigail Wexner Research Institute at Nationwide Children's Hospital Columbus OH USA.,Department of Pediatrics The Ohio State University College of Medicine Columbus OH USA
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15
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Han X, Hofmann L, de la Fuente M, Alexander N, Palczewski K, Nieman MT. PAR4 activation involves extracellular loop 3 and transmembrane residue Thr153. Blood 2020; 136:2217-2228. [PMID: 32575122 PMCID: PMC7645988 DOI: 10.1182/blood.2019004634] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 05/24/2020] [Indexed: 12/17/2022] Open
Abstract
Protease-activated receptor 4 (PAR4) mediates sustained thrombin signaling in platelets and is required for a stable thrombus. PAR4 is activated by proteolysis of the N terminus to expose a tethered ligand. The structural basis for PAR4 activation and the location of its ligand binding site (LBS) are unknown. Using hydrogen/deuterium exchange (H/D exchange), computational modeling, and signaling studies, we determined the molecular mechanism for tethered ligand-mediated PAR4 activation. H/D exchange identified that the LBS is composed of transmembrane 3 (TM3) domain and TM7. Unbiased computational modeling further predicted an interaction between Gly48 from the tethered ligand and Thr153 from the LBS. Mutating Thr153 significantly decreased PAR4 signaling. H/D exchange and modeling also showed that extracellular loop 3 (ECL3) serves as a gatekeeper for the interaction between the tethered ligand and LBS. A naturally occurring sequence variant (P310L, rs2227376) and 2 experimental mutations (S311A and P312L) determined that the rigidity conferred by prolines in ECL3 are essential for PAR4 activation. Finally, we examined the role of the polymorphism at position 310 in venous thromboembolism (VTE) using the International Network Against Venous Thrombosis (INVENT) consortium multi-ancestry genome-wide association study (GWAS) meta-analysis. Individuals with the PAR4 Leu310 allele had a 15% reduction in relative risk for VTE (odds ratio, 0.85; 95% confidence interval, 0.77-0.94) compared with the Pro310 allele. These data are consistent with our H/D exchange, molecular modeling, and signaling studies. In conclusion, we have uncovered the structural basis for PAR4 activation and identified a previously unrecognized role for PAR4 in VTE.
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Affiliation(s)
- Xu Han
- Case Western Reserve University, School of Medicine, Cleveland, OH; and
| | - Lukas Hofmann
- Case Western Reserve University, School of Medicine, Cleveland, OH; and
| | | | - Nathan Alexander
- Case Western Reserve University, School of Medicine, Cleveland, OH; and
| | | | - Marvin T Nieman
- Case Western Reserve University, School of Medicine, Cleveland, OH; and
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16
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Antagonism of Protease-Activated Receptor 4 Protects Against Traumatic Brain Injury by Suppressing Neuroinflammation via Inhibition of Tab2/NF-κB Signaling. Neurosci Bull 2020; 37:242-254. [PMID: 33111257 DOI: 10.1007/s12264-020-00601-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 07/19/2020] [Indexed: 12/23/2022] Open
Abstract
Traumatic brain injury (TBI) triggers the activation of the endogenous coagulation mechanism, and a large amount of thrombin is released to curb uncontrollable bleeding through thrombin receptors, also known as protease-activated receptors (PARs). However, thrombin is one of the most critical factors in secondary brain injury. Thus, the PARs may be effective targets against hemorrhagic brain injury. Since the PAR1 antagonist has an increased bleeding risk in clinical practice, PAR4 blockade has been suggested as a more promising treatment. Here, we explored the expression pattern of PAR4 in the brain of mice after TBI, and explored the effect and possible mechanism of BMS-986120 (BMS), a novel selective and reversible PAR4 antagonist on secondary brain injury. Treatment with BMS protected against TBI in mice. mRNA-seq analysis, Western blot, and qRT-PCR verification in vitro showed that BMS significantly inhibited thrombin-induced inflammation in astrocytes, and suggested that the Tab2/ERK/NF-κB signaling pathway plays a key role in this process. Our findings provide reliable evidence that blocking PAR4 is a safe and effective intervention for TBI, and suggest that BMS has a potential clinical application in the management of TBI.
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17
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Thibeault PE, Ramachandran R. Biased signaling in platelet G-protein coupled receptors. Can J Physiol Pharmacol 2020; 99:255-269. [PMID: 32846106 DOI: 10.1139/cjpp-2020-0149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Platelets are small megakaryocyte-derived, anucleate, disk-like structures that play an outsized role in human health and disease. Both a decrease in the number of platelets and a variety of platelet function disorders result in petechiae or bleeding that can be life threatening. Conversely, the inappropriate activation of platelets, within diseased blood vessels, remains the leading cause of death and morbidity by affecting heart attacks and stroke. The fine balance of the platelet state in healthy individuals is controlled by a number of receptor-mediated signaling pathways that allow the platelet to rapidly respond and maintain haemostasis. G-protein coupled receptors (GPCRs) are particularly important regulators of platelet function. Here we focus on the major platelet-expressed GPCRs and discuss the roles of downstream signaling pathways (e.g., different G-protein subtypes or β-arrestin) in regulating the different phases of the platelet activation. Further, we consider the potential for selectively targeting signaling pathways that may contribute to platelet responses in disease through development of biased agonists. Such selective targeting of GPCR-mediated signaling pathways by drugs, often referred to as biased signaling, holds promise in delivering therapeutic interventions that do not present significant side effects, especially in finely balanced physiological systems such as platelet activation in haemostasis.
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Affiliation(s)
- Pierre E Thibeault
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, ON N6A5C1, Canada
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18
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Thibeault PE, Ramachandran R. Role of the Helix-8 and C-Terminal Tail in Regulating Proteinase Activated Receptor 2 Signaling. ACS Pharmacol Transl Sci 2020; 3:868-882. [PMID: 33073187 DOI: 10.1021/acsptsci.0c00039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Indexed: 12/11/2022]
Abstract
The C-terminal tail of G-protein-coupled receptors (GPCR) contain important regulatory sites that enable interaction with intracellular signaling effectors. Here we examine the relative contribution of the C-tail serine/threonine phosphorylation sites (Ser383-385, Ser387-Thr392) and the helix-8 palmitoylation site (Cys361) in signaling regulation downstream of the proteolytically activated GPCR, PAR2. We examined Gαq/11-coupled calcium signaling, β-arrestin-1/-2 recruitment, and MAPK activation (p44/42 phosphorylation) by wild-type and mutant receptors expressed in a CRISPR/Cas9 PAR2-knockout HEK-293 cell background with both peptide stimulation of the receptor (SLIGRL-NH2) as well as activation with its endogenous trypsin revealed a tethered ligand. We find that alanine substitution of the membrane proximal serine residues (Ser383-385Ala) had no effect on SLIGRL-NH2- or trypsin-stimulated β-arrestin recruitment. In contrast, alanine substitutions in the Ser387-Thr392 cluster resulted in a large (∼50%) decrease in β-arrestin-1/-2 recruitment triggered by the activating peptide, SLIGRL-NH2, but was without an effect on trypsin-activated β-arrestin-1/-2 recruitment. Additionally, we find that alanine substitution of the helix-8 cysteine residue (Cys361Ala) led to a large decrease in both Gαq/11 coupling and β-arrestin-1/-2 recruitment to PAR2. Furthermore, we show that Gαq/11 inhibition with YM254890, inhibited ERK phosphorylation by PAR2 agonists, while genetic deletion of β-arrestin-1/-2 by CRISPR/Cas9 enhanced MAPK activation. Knockout of β-arrestins also enhanced Gαq/11-mediated calcium signaling. In line with these findings, a C-tail serine/threonine mutant that has decreased β-arrestin recruitment also showed enhanced ERK activation. Thus, our studies point to multiple mechanisms that regulate β-arrestin interaction with PAR2 and highlight differences in regulation of tethered-ligand- and peptide-mediated activation of this receptor.
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Affiliation(s)
- Pierre E Thibeault
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A5C1, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A5C1, Canada
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19
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Han X, Nieman MT. The domino effect triggered by the tethered ligand of the protease activated receptors. Thromb Res 2020; 196:87-98. [PMID: 32853981 DOI: 10.1016/j.thromres.2020.08.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/23/2020] [Accepted: 08/03/2020] [Indexed: 12/20/2022]
Abstract
Protease activated receptors (PARs) are G-protein coupled receptors (GPCRs) that have a unique activation mechanism. Unlike other GPCRs that can be activated by free ligands, under physiological conditions, PARs are activated by the tethered ligand, which is a part of their N-terminus that is unmasked by proteolysis. It has been 30 years since the first member of the family, PAR1, was identified. In this review, we will discuss this unique tethered ligand mediate receptor activation of PARs in detail: how they interact with the proteases, the complex structural rearrangement of the receptors upon activation, and the termination of the signaling. We also summarize the structural studies of the PARs and how single nucleotide polymorphisms impact the receptor reactivity. Finally, we review the current strategies for inhibiting PAR function with therapeutic targets for anti-thrombosis. The focus of this review is PAR1 and PAR4 as they are the thrombin signal mediators on human platelets and therapeutics targets. We also include the structural studies of PAR2 as it informs the mechanism of action for PARs in general.
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Affiliation(s)
- Xu Han
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Marvin T Nieman
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA.
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20
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Badaczewska-Dawid AE, Kmiecik S, Koliński M. Docking of peptides to GPCRs using a combination of CABS-dock with FlexPepDock refinement. Brief Bioinform 2020; 22:5855394. [PMID: 32520310 PMCID: PMC8138832 DOI: 10.1093/bib/bbaa109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/19/2022] Open
Abstract
The structural description of peptide ligands bound to G protein-coupled receptors (GPCRs) is important for the discovery of new drugs and deeper understanding of the molecular mechanisms of life. Here we describe a three-stage protocol for the molecular docking of peptides to GPCRs using a set of different programs: (1) CABS-dock for docking fully flexible peptides; (2) PD2 method for the reconstruction of atomistic structures from C-alpha traces provided by CABS-dock and (3) Rosetta FlexPepDock for the refinement of protein–peptide complex structures and model scoring. We evaluated the proposed protocol on the set of seven different GPCR–peptide complexes (including one containing a cyclic peptide), for which crystallographic structures are available. We show that CABS-dock produces high resolution models in the sets of top-scored models. These sets of models, after reconstruction to all-atom representation, can be further improved by Rosetta high-resolution refinement and/or minimization, leading in most of the cases to sub-Angstrom accuracy in terms of interface root-mean-square-deviation measure.
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Affiliation(s)
| | | | - Michał Koliński
- Corresponding author: Michał Koliński, Bioinformatics Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawińskiego St, 02-106 Warsaw, Poland. Tel: (+48) 22 849 93 58; Fax: (+48) 22 668 55 32; E-mail:
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21
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Vanderboor CMG, Thibeault PE, Nixon KCJ, Gros R, Kramer J, Ramachandran R. Proteinase-Activated Receptor 4 Activation Triggers Cell Membrane Blebbing through RhoA and β-Arrestin. Mol Pharmacol 2020; 97:365-376. [PMID: 32234808 DOI: 10.1124/mol.119.118232] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 03/03/2020] [Indexed: 12/22/2022] Open
Abstract
Proteinase-activated receptors (PARs) are a four-member family of G-protein-coupled receptors that are activated via proteolysis. PAR4 is a member of this family that is cleaved and activated by serine proteinases such as thrombin, trypsin, and cathepsin-G. PAR4 is expressed in a variety of tissues and cell types, including platelets, vascular smooth muscle cells, and neuronal cells. In studying PAR4 signaling and trafficking, we observed dynamic changes in the cell membrane, with spherical membrane protrusions that resemble plasma membrane blebbing. Since nonapoptotic membrane blebbing is now recognized as an important regulator of cell migration, cancer cell invasion, and vesicular content release, we sought to elucidate the signaling pathway downstream of PAR4 activation that leads to such events. Using a combination of pharmacological inhibition and CRISPR/CRISPR-associated protein 9 (Cas9)-mediated gene editing approaches, we establish that PAR4-dependent membrane blebbing occurs independently of the Gα q/11- and Gα i-signaling pathways and is dependent on signaling via the β-arrestin-1/2 and Ras homolog family member A (RhoA) signaling pathways. Together these studies provide further mechanistic insight into PAR4 regulation of cellular function. SIGNIFICANCE STATEMENT: We find that the thrombin receptor PAR4 triggers cell membrane blebbing in a RhoA-and β-arrestin-dependent manner. In addition to identifying novel cellular responses mediated by PAR4, these data provide further evidence for biased signaling in PAR4 since membrane blebbing was dependent on some, but not all, signaling pathways activated by PAR4.
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Affiliation(s)
- Christina M G Vanderboor
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Pierre E Thibeault
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Kevin C J Nixon
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Robert Gros
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Jamie Kramer
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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