1
|
Gedam M, Zheng H. Complement C3aR signaling: Immune and metabolic modulation and its impact on Alzheimer's disease. Eur J Immunol 2024:e2350815. [PMID: 38778507 DOI: 10.1002/eji.202350815] [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: 01/27/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia among the elderly population. Despite its widespread prevalence, our comprehension of the intricate mechanisms governing the pathogenesis of the disease remains incomplete, posing a challenge for the development of efficient therapies. Pathologically characterized by the presence of amyloid β plaques and neurofibrillary tau tangles, AD is also accompanied by the hyperactivation of glial cells and the immune system. The complement cascade, the evolutionarily conserved innate immune pathway, has emerged as a significant contributor to AD. This review focuses on one of the complement components, the C3a receptor (C3aR), covering its structure, ligand-receptor interaction, intracellular signaling and its functional consequences. Drawing insights from cellular and AD mouse model studies, we present the multifaceted role of complement C3aR signaling in AD and attempt to convey to the readers that C3aR acts as a crucial immune and metabolic modulator to influence AD pathogenesis. Building on this framework, the objective of this review is to inform future research endeavors and facilitate the development of therapeutic strategies for this challenging condition.
Collapse
Affiliation(s)
- Manasee Gedam
- Department of Molecular and Human Genetics, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas, USA
| | - Hui Zheng
- Department of Molecular and Human Genetics, Huffington Center on Aging, Baylor College of Medicine, Houston, Texas, USA
| |
Collapse
|
2
|
Yadav MK, Maharana J, Yadav R, Saha S, Sarma P, Soni C, Singh V, Saha S, Ganguly M, Li XX, Mohapatra S, Mishra S, Khant HA, Chami M, Woodruff TM, Banerjee R, Shukla AK, Gati C. Molecular basis of anaphylatoxin binding, activation, and signaling bias at complement receptors. Cell 2023; 186:4956-4973.e21. [PMID: 37852260 PMCID: PMC7615941 DOI: 10.1016/j.cell.2023.09.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 07/19/2023] [Accepted: 09/20/2023] [Indexed: 10/20/2023]
Abstract
The complement system is a critical part of our innate immune response, and the terminal products of this cascade, anaphylatoxins C3a and C5a, exert their physiological and pathophysiological responses primarily via two GPCRs, C3aR and C5aR1. However, the molecular mechanism of ligand recognition, activation, and signaling bias of these receptors remains mostly elusive. Here, we present nine cryo-EM structures of C3aR and C5aR1 activated by their natural and synthetic agonists, which reveal distinct binding pocket topologies of complement anaphylatoxins and provide key insights into receptor activation and transducer coupling. We also uncover the structural basis of a naturally occurring mechanism to dampen the inflammatory response of C5a via proteolytic cleavage of the terminal arginine and the G-protein signaling bias elicited by a peptide agonist of C3aR identified here. In summary, our study elucidates the innerworkings of the complement anaphylatoxin receptors and should facilitate structure-guided drug discovery to target these receptors in a spectrum of disorders.
Collapse
Affiliation(s)
- Manish K Yadav
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Jagannath Maharana
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Ravi Yadav
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA; The Bridge Institute, Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA
| | - Shirsha Saha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Parishmita Sarma
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Chahat Soni
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Vinay Singh
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Sayantan Saha
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Manisankar Ganguly
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Xaria X Li
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Samanwita Mohapatra
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Sudha Mishra
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Htet A Khant
- USC Center of Excellence for Nano-Imaging, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
| | - Mohamed Chami
- BioEM Lab, Biozentrum, Universität Basel, Basel, Switzerland
| | - Trent M Woodruff
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Ramanuj Banerjee
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India.
| | - Arun K Shukla
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India.
| | - Cornelius Gati
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA; The Bridge Institute, Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA; Department of Chemistry, Department of Quantitative and Computational Biology, Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
3
|
Sahu BS, Nguyen ME, Rodriguez P, Pallais JP, Ghosh V, Razzoli M, Sham YY, Salton SR, Bartolomucci A. The molecular identity of the TLQP-21 peptide receptor. Cell Mol Life Sci 2021; 78:7133-7144. [PMID: 34626205 PMCID: PMC8629782 DOI: 10.1007/s00018-021-03944-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 09/08/2021] [Accepted: 09/15/2021] [Indexed: 11/30/2022]
Abstract
The TLQP-21 neuropeptide has been implicated in functions as diverse as lipolysis, neurodegeneration and metabolism, thus suggesting an important role in several human diseases. Three binding targets have been proposed for TLQP-21: C3aR1, gC1qR and HSPA8. The aim of this review is to critically evaluate the molecular identity of the TLQP-21 receptor and the proposed multi-receptor mechanism of action. Several studies confirm a critical role for C3aR1 in TLQP-21 biological activity and a largely conserved mode of binding, receptor activation and signaling with C3a, its first-identified endogenous ligand. Conversely, data supporting a role of gC1qR and HSPA8 in TLQP-21 activity remain limited, with no signal transduction pathways being described. Overall, C3aR1 is the only receptor for which a necessary and sufficient role in TLQP-21 activity has been confirmed thus far. This conclusion calls into question the validity of a multi-receptor mechanism of action for TLQP-21 and should inform future studies.
Collapse
Affiliation(s)
- Bhavani S Sahu
- National Brain Research Centre, NH-8, Manesar, Gurugram, Haryana, 122052, India
| | - Megin E Nguyen
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA
- Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, USA
| | - Pedro Rodriguez
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA
| | - Jean Pierre Pallais
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA
| | - Vinayak Ghosh
- National Brain Research Centre, NH-8, Manesar, Gurugram, Haryana, 122052, India
| | - Maria Razzoli
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA
| | - Yuk Y Sham
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA
- Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, USA
| | - Stephen R Salton
- Departments of Neuroscience and Geriatrics and Palliative Medicine, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Alessandro Bartolomucci
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6th St. SE, Minneapolis, MN, 55455, USA.
| |
Collapse
|
4
|
Misawa K, Sugai Y, Fujimori T, Hirokawa T. Structural insights from an in silico molecular docking simulation of complement component 3a receptor 1 with an antagonist. J Mol Graph Model 2021; 106:107914. [PMID: 33932736 DOI: 10.1016/j.jmgm.2021.107914] [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: 11/20/2020] [Revised: 03/29/2021] [Accepted: 03/29/2021] [Indexed: 11/18/2022]
Abstract
Complement component 3a receptor 1 (C3aR) is an anaphylatoxin receptor that mediates inflammatory processes. Although considerable effort has gone into discovering the antagonists and agonists of C3aR, structural insights are required to search for effective ligands and to elucidate their binding modes and the mechanism of activation and inactivation. No experimental structural data of C3aR have yet been reported. We investigated the binding mode of an antagonist of C3aR using a combination of homology modeling, ligand docking, molecular dynamics simulations, and binding free energy calculations. We produced a plausible binding model consistent with the reported experimental data. We believe that this model is appropriate for the identification of new C3aR antagonists, as it can distinguish between antagonists and decoy compounds.
Collapse
Affiliation(s)
- Kensuke Misawa
- Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi, 321-3497, Japan.
| | - Yoshiya Sugai
- Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi, 321-3497, Japan
| | - Taketoshi Fujimori
- Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga-gun, Tochigi, 321-3497, Japan
| | - Takatsugu Hirokawa
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 2-4-7 Aomi, Koto-ku, Tokyo, 135-0064, Japan; Transborder Medical Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan; Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan.
| |
Collapse
|
5
|
Vandendriessche S, Cambier S, Proost P, Marques PE. Complement Receptors and Their Role in Leukocyte Recruitment and Phagocytosis. Front Cell Dev Biol 2021; 9:624025. [PMID: 33644062 PMCID: PMC7905230 DOI: 10.3389/fcell.2021.624025] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/15/2021] [Indexed: 12/21/2022] Open
Abstract
The complement system is deeply embedded in our physiology and immunity. Complement activation generates a multitude of molecules that converge simultaneously on the opsonization of a target for phagocytosis and activation of the immune system via soluble anaphylatoxins. This response is used to control microorganisms and to remove dead cells, but also plays a major role in stimulating the adaptive immune response and the regeneration of injured tissues. Many of these effects inherently depend on complement receptors expressed on leukocytes and parenchymal cells, which, by recognizing complement-derived molecules, promote leukocyte recruitment, phagocytosis of microorganisms and clearance of immune complexes. Here, the plethora of information on the role of complement receptors will be reviewed, including an analysis of how this functionally and structurally diverse group of molecules acts jointly to exert the full extent of complement regulation of homeostasis.
Collapse
Affiliation(s)
- Sofie Vandendriessche
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| | - Seppe Cambier
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| | - Paul Proost
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| | - Pedro E Marques
- Laboratory of Molecular Immunology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| |
Collapse
|
6
|
Sahu BS, Rodriguez P, Nguyen ME, Han R, Cero C, Razzoli M, Piaggi P, Laskowski LJ, Pavlicev M, Muglia L, Mahata SK, O'Grady S, McCorvy JD, Baier LJ, Sham YY, Bartolomucci A. Peptide/Receptor Co-evolution Explains the Lipolytic Function of the Neuropeptide TLQP-21. Cell Rep 2019; 28:2567-2580.e6. [PMID: 31484069 PMCID: PMC6753381 DOI: 10.1016/j.celrep.2019.07.101] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 06/11/2019] [Accepted: 07/26/2019] [Indexed: 12/24/2022] Open
Abstract
Structural and functional diversity of peptides and GPCR result from long evolutionary processes. Even small changes in sequence can alter receptor activation, affecting therapeutic efficacy. We conducted a structure-function relationship study on the neuropeptide TLQP-21, a promising target for obesity, and its complement 3a receptor (C3aR1). After having characterized the TLQP-21/C3aR1 lipolytic mechanism, a homology modeling and molecular dynamics simulation identified the TLQP-21 binding motif and C3aR1 binding site for the human (h) and mouse (m) molecules. mTLQP-21 showed enhanced binding affinity and potency for hC3aR1 compared with hTLQP-21. Consistently, mTLQP-21, but not hTLQP-21, potentiates lipolysis in human adipocytes. These findings led us to uncover five mutations in the C3aR1 binding pocket of the rodent Murinae subfamily that are causal for enhanced calculated affinity and measured potency of TLQP-21. Identifying functionally relevant peptide/receptor co-evolution mechanisms can facilitate the development of innovative pharmacotherapies for obesity and other diseases implicating GPCRs.
Collapse
Affiliation(s)
- Bhavani S Sahu
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Pedro Rodriguez
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Megin E Nguyen
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Ruijun Han
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Cheryl Cero
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Maria Razzoli
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA
| | - Paolo Piaggi
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Phoenix, AZ, USA
| | - Lauren J Laskowski
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Mihaela Pavlicev
- Division of Human Genetics, Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Louis Muglia
- Division of Human Genetics, Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Sushil K Mahata
- VA San Diego Healthcare System, San Diego, CA, USA; Department of Medicine, University of California at San Diego, La Jolla, CA, USA
| | - Scott O'Grady
- Department of Animal Science, University of Minnesota, 480 Haecker Hall, 1364 Eckles Avenue, St. Paul, MN, USA
| | - John D McCorvy
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Leslie J Baier
- Phoenix Epidemiology and Clinical Research Branch, National Institute of Diabetes, Digestive and Kidney Diseases, NIH, Phoenix, AZ, USA
| | - Yuk Y Sham
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA; Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, MN, USA
| | - Alessandro Bartolomucci
- Department of Integrative Biology and Physiology, University of Minnesota, 2231 6(th) St. SE, Minneapolis, MN, USA.
| |
Collapse
|
7
|
Dantas de Araujo A, Wu C, Wu KC, Reid RC, Durek T, Lim J, Fairlie DP. Europium-Labeled Synthetic C3a Protein as a Novel Fluorescent Probe for Human Complement C3a Receptor. Bioconjug Chem 2017; 28:1669-1676. [DOI: 10.1021/acs.bioconjchem.7b00132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Aline Dantas de Araujo
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Chongyang Wu
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Kai-Chen Wu
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Robert C. Reid
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Thomas Durek
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Junxian Lim
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David P. Fairlie
- Division of Chemistry and Structural Biology, Institute for Molecular
Bioscience, ‡Australian Research Council Centre of Excellence in Advanced Molecular
Imaging, Institute for Molecular Bioscience, and §Centre for Inflammation Disease Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
8
|
Potent complement C3a receptor agonists derived from oxazole amino acids: Structure–activity relationships. Bioorg Med Chem Lett 2015; 25:5604-8. [DOI: 10.1016/j.bmcl.2015.10.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/12/2015] [Accepted: 10/14/2015] [Indexed: 12/11/2022]
|
9
|
Barnum SR. C4a: An Anaphylatoxin in Name Only. J Innate Immun 2015; 7:333-9. [PMID: 25659340 DOI: 10.1159/000371423] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 12/08/2014] [Indexed: 12/31/2022] Open
Abstract
Activation of complement leads to generation of the 3 anaphylatoxins C3a, C4a, and C5a. Although all 3 peptides are structurally similar, only C3a and C5a share a similar functional profile that includes the classic inflammatory activities and, more recently, developmental homing and regenerative properties among others. In contrast, the functional profile of C4a is questionable in most cases owing to contamination of C4a preparations with physiologically relevant levels of C3a and/or C5a. Combined with the absence of an identified C4a receptor and the inability of C4a to signal through the C3a and C5a receptors, it is clear that C4a should not be included in the family of complement anaphylatoxins.
Collapse
Affiliation(s)
- Scott R Barnum
- Departments of Microbiology and Neurobiology, University of Alabama at Birmingham, Birmingham, Ala., USA
| |
Collapse
|
10
|
Reid RC, Yau MK, Singh R, Hamidon JK, Lim J, Stoermer MJ, Fairlie DP. Potent Heterocyclic Ligands for Human Complement C3a Receptor. J Med Chem 2014; 57:8459-70. [DOI: 10.1021/jm500956p] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Robert C. Reid
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Mei-Kwan Yau
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Ranee Singh
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Johan K. Hamidon
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Junxian Lim
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Martin J. Stoermer
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David P. Fairlie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
11
|
Reid RC, Yau MK, Singh R, Hamidon JK, Reed AN, Chu P, Suen JY, Stoermer MJ, Blakeney JS, Lim J, Faber JM, Fairlie DP. Downsizing a human inflammatory protein to a small molecule with equal potency and functionality. Nat Commun 2014; 4:2802. [PMID: 24257095 DOI: 10.1038/ncomms3802] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 10/21/2013] [Indexed: 01/20/2023] Open
Abstract
A significant challenge in chemistry is to rationally reproduce the functional potency of a protein in a small molecule, which is cheaper to manufacture, non-immunogenic, and also both stable and bioavailable. Synthetic peptides corresponding to small bioactive protein surfaces do not form stable structures in water and do not exhibit the functional potencies of proteins. Here we describe a novel approach to growing small molecules with protein-like potencies from a functionally important amino acid of a protein. A 77-residue human inflammatory protein (complement C3a) important in innate immunity is rationally transformed to equipotent small molecules, using peptide surrogates that incorporate a turn-inducing heterocycle with correctly positioned hydrogen-bond-accepting atoms. Small molecule agonists (molecular weight <500 Da) examined for receptor affinity and cellular responses have the same high potencies, functional profile and specificity of action as C3a protein, but greater plasma stability and bioavailability.
Collapse
Affiliation(s)
- Robert C Reid
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Gupta A, Rezvani R, Lapointe M, Poursharifi P, Marceau P, Tiwari S, Tchernof A, Cianflone K. Downregulation of complement C3 and C3aR expression in subcutaneous adipose tissue in obese women. PLoS One 2014; 9:e95478. [PMID: 24743347 PMCID: PMC3990631 DOI: 10.1371/journal.pone.0095478] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 03/27/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND The central component of the complement system, C3, is associated with obesity, metabolic syndrome and cardiovascular disease however the underlying reasons are unknown. In the present study we evaluated gene expression of C3, the cleavage product C3a/C3adesArg and its cognate receptor C3aR in subcutaneous and omental adipose tissue in women. METHODS Women (n = 140, 21-69 years, BMI 19.5-79 kg/m2) were evaluated for anthropometric and blood parameters, and adipose tissue gene expression. RESULTS Subjects were separated into groups (n = 34-36) according to obesity: normal/overweight (≤30 kg/m2), obese I (≤45 kg/m2), obese II (≤51 kg/m2), and obese III (≤80 kg/m2). Overall, while omental expression remained unchanged, subcutaneous C3 and C3aR gene expression decreased with increasing adiposity (2-way ANOVA, p<0.01), with a concomitant decrease in SC/OM ratio (p<0.001). In subcutaneous adipose, both C3 and C3aR expression correlated with apoB, and apoA1 and inversely with waist circumference and blood pressure, while C3aR also correlated with glucose (p<0.05-0.0001). While omental C3aR expression did not correlate with any factor, omental C3 correlated with waist circumference, glucose and apoB (all p<0.05). Further, while plasma C3a/C3adesArg increased and adiponectin decreased with increasing BMI, both correlated (C3a negatively and adiponectin positively) with subcutaneous C3 and C3aR expression (p<0.05-0.001) or less). CONCLUSIONS The obesity-induced down-regulation of complement C3 and C3aR which is specific to subcutaneous adipose tissue, coupled to the strong correlations with multiple anthropometric, plasma and adipokine variables support a potential role for complement in immunometabolism.
Collapse
Affiliation(s)
- Abhishek Gupta
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
- Department of Physiology, King George’s Medical University, Lucknow, Uttar Pradesh, India
| | - Reza Rezvani
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
| | - Marc Lapointe
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
| | - Pegah Poursharifi
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
| | - Picard Marceau
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
| | - Sunita Tiwari
- Department of Physiology, King George’s Medical University, Lucknow, Uttar Pradesh, India
| | - Andre Tchernof
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
| | - Katherine Cianflone
- Centre de Recherche Institut Universitaire de Cardiologie & Pneumologie de Québec, Université Laval, Québec, Canada
- * E-mail:
| |
Collapse
|
13
|
Klos A, Wende E, Wareham KJ, Monk PN. International Union of Basic and Clinical Pharmacology. [corrected]. LXXXVII. Complement peptide C5a, C4a, and C3a receptors. Pharmacol Rev 2013; 65:500-43. [PMID: 23383423 DOI: 10.1124/pr.111.005223] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The activation of the complement cascade, a cornerstone of the innate immune response, produces a number of small (74-77 amino acid) fragments, originally termed anaphylatoxins, that are potent chemoattractants and secretagogues that act on a wide variety of cell types. These fragments, C5a, C4a, and C3a, participate at all levels of the immune response and are also involved in other processes such as neural development and organ regeneration. Their primary function, however, is in inflammation, so they are important targets for the development of antiinflammatory therapies. Only three receptors for complement peptides have been found, but there are no satisfactory antagonists as yet, despite intensive investigation. In humans, there is a single receptor for C3a (C3a receptor), no known receptor for C4a, and two receptors for C5a (C5a₁ receptor and C5a₂ receptor). The most recently characterized receptor, the C5a₂ receptor (previously known as C5L2 or GPR77), has been regarded as a passive binding protein, but signaling activities are now ascribed to it, so we propose that it be formally identified as a receptor and be given a name to reflect this. Here, we describe the complex biology of the complement peptides, introduce a new suggested nomenclature, and review our current knowledge of receptor pharmacology.
Collapse
Affiliation(s)
- Andreas Klos
- Department for Medical Microbiology, Medical School Hannover, Hannover, Germany
| | | | | | | |
Collapse
|
14
|
Bellows-Peterson ML, Fung HK, Floudas CA, Kieslich CA, Zhang L, Morikis D, Wareham KJ, Monk PN, Hawksworth OA, Woodruff T. De novo peptide design with C3a receptor agonist and antagonist activities: theoretical predictions and experimental validation. J Med Chem 2012; 55:4159-68. [PMID: 22500977 PMCID: PMC3349770 DOI: 10.1021/jm201609k] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Targeting the complement component 3a receptor (C3aR) with selective agonists or antagonists is believed to be a viable therapeutic option for several diseases such as stroke, heart attack, reperfusion injuries, and rheumatoid arthritis. We designed a number of agonists, partial agonists, and antagonists of C3aR using our two-stage de novo protein design framework. Of the peptides tested using a degranulation assay in C3aR-transfected rat basophilic leukemia cells, two were prominent agonists (EC(50) values of 25.3 and 66.2 nM) and two others were partial agonists (IC(50) values of 15.4 and 26.1 nM). Further testing of these lead compounds in a calcium flux assay in U937 cells yielded similar results although with reduced potencies compared to transfected cells. The partial agonists also displayed full antagonist activity when tested in a C3aR inhibition assay. In addition, the electrostatic potential profile was shown to potentially discriminate between full agonists and partial agonists.
Collapse
Affiliation(s)
| | - Ho Ki Fung
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ
| | | | - Chris A. Kieslich
- Department of Bioengineering, University of California at Riverside, Riverside, CA
| | - Li Zhang
- Department of Bioengineering, University of California at Riverside, Riverside, CA
| | - Dimitrios Morikis
- Department of Bioengineering, University of California at Riverside, Riverside, CA
| | - Kathryn J. Wareham
- Department of Infection and Immunity, The University of Sheffield Medical School, Sheffield, UK
| | - Peter N. Monk
- Department of Infection and Immunity, The University of Sheffield Medical School, Sheffield, UK
| | - Owen A. Hawksworth
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| | - Trent Woodruff
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| |
Collapse
|
15
|
Monk PN, Scola AM, Madala P, Fairlie DP. Function, structure and therapeutic potential of complement C5a receptors. Br J Pharmacol 2007; 152:429-48. [PMID: 17603557 PMCID: PMC2050825 DOI: 10.1038/sj.bjp.0707332] [Citation(s) in RCA: 297] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Complement fragment (C)5a is a 74 residue pro-inflammatory polypeptide produced during activation of the complement cascade of serum proteins in response to foreign surfaces such as microorganisms and tissue damaged by physical or chemical injury. C5a binds to at least two seven-transmembrane domain receptors, C5aR (C5R1, CD88) and C5L2 (gpr77), expressed ubiquitously on a wide variety of cells but particularly on the surface of immune cells like macrophages, neutrophils and T cells. C5aR is a classical G protein-coupled receptor that signals through G alpha i and G alpha 16, whereas C5L2 does not appear to couple to G proteins and has no known signalling activity. Although C5a was first described as an anaphylatoxin and later as a leukocyte chemoattractant, the widespread expression of C5aR suggested more general functionality. Our understanding of the physiology of C5a has improved significantly in recent years through exploitation of receptor knockout and knocking mice, C5 and C5a antibodies, soluble recombinant C5a and C5a analogues and newly developed receptor antagonists. C5a is now also implicated in non-immunological functions associated with developmental biology, CNS development and neurodegeneration, tissue regeneration, and haematopoiesis. Combined receptor mutagenesis, molecular modelling, structure-activity relationship studies and species dependence for ligand potency on C5aR have been helpful for identifying ligand binding sites on the receptor and for defining mechanisms of receptor activation and inactivation. This review will highlight major developments in C5a receptor research that support C5aR as an important therapeutic target. The intriguing possibilities raised by the existence of a non-signalling C5a receptor are also discussed.
Collapse
Affiliation(s)
- P N Monk
- Academic Neurology Unit, School of Medicine and Biomedical Science, University of Sheffield, Sheffield, UK.
| | | | | | | |
Collapse
|
16
|
Scola AM, Higginbottom A, Partridge LJ, Reid RC, Woodruff T, Taylor SM, Fairlie DP, Monk PN. The role of the N-terminal domain of the complement fragment receptor C5L2 in ligand binding. J Biol Chem 2006; 282:3664-71. [PMID: 17158873 PMCID: PMC2873560 DOI: 10.1074/jbc.m609178200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
C5L2 is a new cellular receptor found to interact with the human anaphylatoxins complement factor C5a and its C-terminal cleavage product C5a des Arg. The classical human C5a receptor (C5aR) preferentially binds C5a, with a 10-100-fold lower affinity for C5a des Arg. In contrast, C5L2 binds both ligands with nearly equal affinity. C5aR presents acidic and tyrosine residues in its N terminus that interact with the core of C5a while a hydrophobic pocket formed by the transmembrane helices interacts with residues in the C terminus of C5a. Here, we have investigated the molecular basis for the increased affinity of C5L2 for C5a des Arg. Rat and mouse C5L2 preferentially bound C5a des Arg, whereas rodent C5aR showed much higher affinity for intact C5a. Effective peptidic and non-peptidic ligands for the transmembrane hydrophobic pocket of C5aR were poor inhibitors of ligand binding to C5L2. An antibody raised against the N terminus of human C5L2 did not affect the binding of C5a to C5L2 but did inhibit C5a des Arg binding. A chimeric C5L2, containing the N terminus of C5aR, had little effect on the affinity for C5a des Arg. Mutation of acidic and tyrosine residues in the N terminus of human C5L2 revealed that 3 residues were critical for C5a des Arg binding but had little involvement in C5a binding. C5L2 thus appears to bind C5a and C5a des Arg by different mechanisms, and, unlike C5aR, C5L2 uses critical residues in its N-terminal domain for binding only to C5a des Arg.
Collapse
Affiliation(s)
- Anne-Marie Scola
- Academic Neurology Unit and Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2RX, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Higginbottom A, Cain SA, Woodruff TM, Proctor LM, Madala PK, Tyndall JDA, Taylor SM, Fairlie DP, Monk PN. Comparative agonist/antagonist responses in mutant human C5a receptors define the ligand binding site. J Biol Chem 2005; 280:17831-40. [PMID: 15661745 DOI: 10.1074/jbc.m410797200] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The C terminus is responsible for all of the agonist activity of C5a at human C5a receptors (C5aRs). In this report we have mapped the ligand binding site on the C5aR using a series of agonist and antagonist peptide mimics of the C terminus of C5a as well as receptors mutated at putative interaction sites (Ile(116), Arg(175,) Arg(206), Glu(199), Asp(282), and Val(286)). Agonist peptide 1 (Phe-Lys-Pro-d-cyclohexylalanine-cyclohexylalanine-d-Arg) can be converted to an antagonist by substituting the bulkier Trp for cyclohexylalanine at position 5 (peptide 2). Conversely, mutation of C5aR transmembrane residue Ile(116) to the smaller Ala (I116A) makes the receptor respond to peptide 2 as an agonist (Gerber, B. O., Meng, E. C., Dotsch, V., Baranski, T. J., and Bourne, H. R. (2001) J. Biol. Chem. 276, 3394-3400). However, a potent cyclic hexapeptide antagonist, Phe-cyclo-[Orn-Pro-d-cyclohexylalanine-Trp-Arg] (peptide 3), derived from peptide 2 and which binds to the same receptor site, remains a full antagonist at I116AC5aR. This suggests that although the residue at position 5 might bind near to Ile(116), the latter is not essential for either activation or antagonism. Arg(206) and Arg(175) both appear to interact with the C-terminal carboxylate of C5a agonist peptides, suggesting a dynamic binding mechanism that may be a part of a receptor activation switch. Asp(282) has been previously shown to interact with the side chain of the C-terminal Arg residue, and Glu(199) may also interact with this side chain in both C5a and peptide mimics. Using these interactions to orient NMR-derived ligand structures in the binding site of C5aR, a new model of the interaction between peptide antagonists and the C5aR is presented.
Collapse
Affiliation(s)
- Adrian Higginbottom
- Academic Neurology Unit, University of Sheffield Medical School, Sheffield S10 2RX, United Kingdom
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Qian B, Soyer OS, Neubig RR, Goldstein RA. Depicting a protein's two faces: GPCR classification by phylogenetic tree-based HMMs. FEBS Lett 2003; 554:95-9. [PMID: 14596921 DOI: 10.1016/s0014-5793(03)01112-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Related proteins with similar biological functions generally share common features, allowing us to extract the common sequence features. These common features enable us to build statistical models that can be used to classify proteins, to predict new members, and to study the sequence-function relationship of this protein function group. Although evolution underlies the basis of multiple sequence analysis methods, most methods ignore phylogenetic relationships and the evolutionary process in building these statistical models. Previously we have shown that a phylogenetic tree-based profile hidden Markov model (T-HMM) is superior in generating a profile for a group of similar proteins. In this study we used the method to generate common features of G protein-coupled receptors (GPCRs). The profile generated by T-HMM gives high accuracy in GPCR function classification, both by ligand and by coupled G protein.
Collapse
Affiliation(s)
- Bin Qian
- Biophysics Research Division, University of Michigan, Ann Arbor, MI 48105, USA
| | | | | | | |
Collapse
|
19
|
Cain SA, Higginbottom A, Monk PN. Characterisation of C5a receptor agonists from phage display libraries. Biochem Pharmacol 2003; 66:1833-40. [PMID: 14563493 DOI: 10.1016/s0006-2952(03)00473-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
C5a des-Arg(74) has a 10- to 100-fold lower receptor binding affinity than intact C5a and is only a partial agonist. We have used phage display selection from randomly mutated C5a des-Arg(74) libraries to isolate variant proteins that can activate C5a receptors with similar potency to C5a. Here we explore the interactions of three variants (V1-3) with C5aR mutated at residues involved in the differential response. The mutant Asp(282)Arg-C5aR is preferentially activated by C5a des-Arg(74), probably due to repulsion between Arg(74) of C5a and the substituent Arg(282). In accordance with this hypothesis, V2 (with a polar C-terminus which has no Arg residue) but not V1 (with a C-terminal Arg residue at position 73) could activate Asp(282)Arg-C5aR. V3, with a very hydrophobic C-terminus, was the most potent agonist at Asp(282)Arg-C5aR. Arg(175) is a potential counterion for the C-terminal carboxylate of C5a. C5aR mutated to either Ala or Asp at this position lost nearly all responsiveness to both C5a and C5a des-Arg(74), suggesting that mutation of Arg(175) caused a non-specific loss of receptor conformation and a loss of signalling capacity. However, V3 could still activate Arg(175)Asp/Ala-C5aR with the same potency as wild-type C5aR, demonstrating that the mutant receptors retained high signalling capability and showed a specific loss of responsiveness. Thus C5a des-Arg(74) variants produced by phage display are potentially useful tools for the dissection of ligand-receptor interactions.
Collapse
Affiliation(s)
- Stuart A Cain
- Academic Neurology Unit, University of Sheffield Medical School, Sheffield S10 2RX, UK
| | | | | |
Collapse
|
20
|
Jagels MA, Daffern PJ, Hugli TE. C3a and C5a enhance granulocyte adhesion to endothelial and epithelial cell monolayers: epithelial and endothelial priming is required for C3a-induced eosinophil adhesion. IMMUNOPHARMACOLOGY 2000; 46:209-22. [PMID: 10741901 DOI: 10.1016/s0162-3109(99)00178-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Effects of the anaphylatoxins C3a and C5a on eosinophil and neutrophil adhesion to HUVEC and to primary culture human bronchial epithelial cells (HBEC) were investigated. Activities on both leukocytes and on structural cells were examined. C3a upregulated beta2 integrin expression and caused shedding of L-selectin on eosinophils, but had no effect on neutrophil adhesion molecule expression. C5a upregulated beta2 integrins and caused shedding of L-selectin on both eosinophils and neutrophils. The potency of C5a was equivalent on both cell types; however, the magnitude of the changes in each of these adhesion molecules was significantly greater in neutrophils than eosinophils. Neither C3a nor C5a altered expression of ICAM-1, VCAM-1, E-selectin or P-selectin on either HUVEC or HBEC. C5a induced adhesion of both neutrophils and eosinophils to unstimulated HUVEC or HBEC, and adhesion was further enhanced when HUVEC and HBEC were "primed" with TNF-alpha and IFN-gamma, respectively. C3a failed to enhance adhesion of either eosinophils or neutrophils to unprimed HUVEC or HBEC, and enhanced only eosinophil adhesion to cytokine-primed HUVEC or HBEC. Similar to C3a, C3a(desArg) and a C3a-analog peptide E7 also enhanced eosinophil adhesion only to cytokine-primed HUVEC and HBEC. These results support the traditional view of anaphylatoxins as leukocyte-specific mediators. The specificity of C3a for eosinophils implicates this molecule as a potential participant in allergic inflammation. The pro-adhesive effects of C3a(desArg) suggest that this molecule, previously characterized as a spasmogenically inactive derivative of C3a, may also alter leukocyte dynamics and migration. Finally, activation of endothelium may represent an important control mechanism for C3a-mediated adhesion preventing unchecked eosinophil adhesion to uninflamed systemic vasculature.
Collapse
Affiliation(s)
- M A Jagels
- Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | | | | |
Collapse
|