1
|
Kayastha K, Zhou Y, Brünle S. Structural perspectives on chemokine receptors. Biochem Soc Trans 2024; 52:1011-1024. [PMID: 38856028 DOI: 10.1042/bst20230358] [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: 02/14/2024] [Revised: 05/02/2024] [Accepted: 05/07/2024] [Indexed: 06/11/2024]
Abstract
Chemokine receptors are integral to the immune system and prime targets in drug discovery that have undergone extensive structural elucidation in recent years. We outline a timeline of these structural achievements, discuss the intracellular negative allosteric modulation of chemokine receptors, analyze the mechanisms of orthosteric receptor activation, and report on the emerging concept of biased signaling. Additionally, we highlight differences of G-protein binding among chemokine receptors. Intracellular allosteric modulators in chemokine receptors interact with a conserved motif within transmembrane helix 7 and helix 8 and exhibit a two-fold inactivation mechanism that can be harnessed for drug-discovery efforts. Chemokine recognition is a multi-step process traditionally explained by a two-site model within chemokine recognition site 1 (CRS1) and CRS2. Recent structural studies have extended our understanding of this complex mechanism with the identification of CRS1.5 and CRS3. CRS3 is implicated in determining ligand specificity and surrounds the chemokine by almost 180°. Within CRS3 we identified the extracellular loop 2 residue 45.51 as a key interaction mediator for chemokine binding. Y2917.43 on the other hand was shown in CCR1 to be a key determinant of signaling bias which, along with specific chemokine-dependent phosphorylation ensembles at the G-protein coupled receptors (GPCR's) C-terminus, seems to play a pivotal role in determining the direction of signal bias in GPCRs.
Collapse
Affiliation(s)
- Kanwal Kayastha
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Yangli Zhou
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Steffen Brünle
- Leiden Institute of Chemistry, Faculty of Science, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| |
Collapse
|
2
|
Schafer CT, Pauszek RF, Gustavsson M, Handel TM, Millar DP. Distinct Activation Mechanisms of CXCR4 and ACKR3 Revealed by Single-Molecule Analysis of their Conformational Landscapes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.10.31.564925. [PMID: 37961571 PMCID: PMC10635023 DOI: 10.1101/2023.10.31.564925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The canonical chemokine receptor CXCR4 and atypical receptor ACKR3 both respond to CXCL12 but induce different effector responses to regulate cell migration. While CXCR4 couples to G proteins and directly promotes cell migration, ACKR3 is G protein-independent and scavenges CXCL12 to regulate extracellular chemokine levels and maintain CXCR4 responsiveness, thereby indirectly influencing migration. The receptors also have distinct activation requirements. CXCR4 only responds to wild-type CXCL12 and is sensitive to mutation of the chemokine. By contrast, ACKR3 recruits GPCR kinases (GRKs) and β-arrestins and promiscuously responds to CXCL12, CXCL12 variants, other peptides and proteins, and is relatively insensitive to mutation. To investigate the role of conformational dynamics in the distinct pharmacological behaviors of CXCR4 and ACKR3, we employed single-molecule FRET to track discrete conformational states of the receptors in real-time. The data revealed that apo-CXCR4 preferentially populates a high-FRET inactive state, while apo-ACKR3 shows little conformational preference and high transition probabilities among multiple inactive, intermediate and active conformations, consistent with its propensity for activation. Multiple active-like ACKR3 conformations are populated in response to agonists, compared to the single CXCR4 active-state. This and the markedly different conformational landscapes of the receptors suggest that activation of ACKR3 may be achieved by a broader distribution of conformational states than CXCR4. Much of the conformational heterogeneity of ACKR3 is linked to a single residue that differs between ACKR3 and CXCR4. The dynamic properties of ACKR3 may underly its inability to form productive interactions with G proteins that would drive canonical GPCR signaling.
Collapse
Affiliation(s)
- Christopher T. Schafer
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology, University of California San Diego, La Jolla, CA 92037
| | - Raymond F. Pauszek
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037
| | - Martin Gustavsson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology, University of California San Diego, La Jolla, CA 92037
| | - Tracy M. Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology, University of California San Diego, La Jolla, CA 92037
| | - David P. Millar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037
| |
Collapse
|
3
|
Urvas L, Chiesa L, Bret G, Jacquemard C, Kellenberger E. Benchmarking AlphaFold-Generated Structures of Chemokine-Chemokine Receptor Complexes. J Chem Inf Model 2024; 64:4587-4600. [PMID: 38809680 DOI: 10.1021/acs.jcim.3c01835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
AlphaFold and AlphaFold-Multimer have become two essential tools for the modeling of unknown structures of proteins and protein complexes. In this work, we extensively benchmarked the quality of chemokine-chemokine receptor structures generated by AlphaFold-Multimer against experimentally determined structures. Our analysis considered both the global quality of the model, as well as key structural features for chemokine recognition. To study the effects of template and multiple sequence alignment parameters on the results, a new prediction pipeline called LIT-AlphaFold (https://github.com/LIT-CCM-lab/LIT-AlphaFold) was developed, allowing extensive input customization. AlphaFold-Multimer correctly predicted differences in chemokine binding orientation and accurately reproduced the unique binding orientation of the CXCL12-ACKR3 complex. Further, the predictions of the full receptor N-terminus provided insights into a putative chemokine recognition site 0.5. The accuracy of chemokine N-terminus binding mode prediction varied between complexes, but the confidence score permitted the distinguishing of residues that were very likely well positioned. Finally, we generated a high-confidence model of the unsolved CXCL12-CXCR4 complex, which agreed with experimental mutagenesis and cross-linking data.
Collapse
Affiliation(s)
- Lauri Urvas
- Laboratoire d'Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, 67400 Illkirch, France
| | - Luca Chiesa
- Laboratoire d'Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, 67400 Illkirch, France
| | - Guillaume Bret
- Laboratoire d'Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, 67400 Illkirch, France
| | - Célien Jacquemard
- Laboratoire d'Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, 67400 Illkirch, France
| | - Esther Kellenberger
- Laboratoire d'Innovation Thérapeutique, UMR 7200 CNRS, Université de Strasbourg, 67400 Illkirch, France
| |
Collapse
|
4
|
Roy S, Sinha S, Silas AJ, Ghassemian M, Kufareva I, Ghosh P. Growth factor-dependent phosphorylation of Gα i shapes canonical signaling by G protein-coupled receptors. Sci Signal 2024; 17:eade8041. [PMID: 38833528 DOI: 10.1126/scisignal.ade8041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 05/17/2024] [Indexed: 06/06/2024]
Abstract
A long-standing question in the field of signal transduction is how distinct signaling pathways interact with each other to control cell behavior. Growth factor receptors and G protein-coupled receptors (GPCRs) are the two major signaling hubs in eukaryotes. Given that the mechanisms by which they signal independently have been extensively characterized, we investigated how they may cross-talk with each other. Using linear ion trap mass spectrometry and cell-based biophysical, biochemical, and phenotypic assays, we found at least three distinct ways in which epidermal growth factor affected canonical G protein signaling by the Gi-coupled GPCR CXCR4 through the phosphorylation of Gαi. Phosphomimicking mutations in two residues in the αE helix of Gαi (tyrosine-154/tyrosine-155) suppressed agonist-induced Gαi activation while promoting constitutive Gβγ signaling. Phosphomimicking mutations in the P loop (serine-44, serine-47, and threonine-48) suppressed Gi activation entirely, thus completely segregating growth factor and GPCR pathways. As expected, most of the phosphorylation events appeared to affect intrinsic properties of Gαi proteins, including conformational stability, nucleotide binding, and the ability to associate with and to release Gβγ. However, one phosphomimicking mutation, targeting the carboxyl-terminal residue tyrosine-320, promoted mislocalization of Gαi from the plasma membrane, a previously uncharacterized mechanism of suppressing GPCR signaling through G protein subcellular compartmentalization. Together, these findings elucidate not only how growth factor and chemokine signals cross-talk through the phosphorylation-dependent modulation of Gαi but also how such cross-talk may generate signal diversity.
Collapse
Affiliation(s)
- Suchismita Roy
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, CA 92093, USA
| | - Saptarshi Sinha
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, CA 92093, USA
| | - Ananta James Silas
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, CA 92093, USA
| | - Majid Ghassemian
- Department of Chemistry and Biochemistry, Biomolecular and Proteomics Mass Spectrometry Facility, University of California San Diego, San Diego, CA 92093, USA
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA 92093, USA
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, CA 92093, USA
- Department of Medicine, University of California San Diego, San Diego, CA 92093, USA
- Moores Comprehensive Cancer Center, University of California San Diego, San Diego, CA 92093, USA
| |
Collapse
|
5
|
Mantonico MV, De Leo F, Quilici G, Colley LS, De Marchis F, Crippa M, Mezzapelle R, Schulte T, Zucchelli C, Pastorello C, Carmeno C, Caprioglio F, Ricagno S, Giachin G, Ghitti M, Bianchi ME, Musco G. The acidic intrinsically disordered region of the inflammatory mediator HMGB1 mediates fuzzy interactions with CXCL12. Nat Commun 2024; 15:1201. [PMID: 38331917 PMCID: PMC10853541 DOI: 10.1038/s41467-024-45505-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 01/26/2024] [Indexed: 02/10/2024] Open
Abstract
Chemokine heterodimers activate or dampen their cognate receptors during inflammation. The CXCL12 chemokine forms with the fully reduced (fr) alarmin HMGB1 a physiologically relevant heterocomplex (frHMGB1•CXCL12) that synergically promotes the inflammatory response elicited by the G-protein coupled receptor CXCR4. The molecular details of complex formation were still elusive. Here we show by an integrated structural approach that frHMGB1•CXCL12 is a fuzzy heterocomplex. Unlike previous assumptions, frHMGB1 and CXCL12 form a dynamic equimolar assembly, with structured and unstructured frHMGB1 regions recognizing the CXCL12 dimerization surface. We uncover an unexpected role of the acidic intrinsically disordered region (IDR) of HMGB1 in heterocomplex formation and its binding to CXCR4 on the cell surface. Our work shows that the interaction of frHMGB1 with CXCL12 diverges from the classical rigid heterophilic chemokines dimerization. Simultaneous interference with multiple interactions within frHMGB1•CXCL12 might offer pharmacological strategies against inflammatory conditions.
Collapse
Affiliation(s)
- Malisa Vittoria Mantonico
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
- School of Medicine, Università Vita e Salute-San Raffaele, Milan, Italy
| | - Federica De Leo
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
- Experimental Therapeutics Program, IFOM ETS - The AIRC Institute of Molecular Oncology and AIRC, Fondazione AIRC per la Ricerca sul Cancro ETS, Milan, Italy
| | - Giacomo Quilici
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Liam Sean Colley
- HMGBiotech S.r.l., 20133, Milan, Italy
- School of Medicine and Surgery, Università Milano-Bicocca, 20126, Milan, Italy
| | - Francesco De Marchis
- School of Medicine, Università Vita e Salute-San Raffaele, Milan, Italy
- Chromatin Dynamics Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Massimo Crippa
- Chromatin Dynamics Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Rosanna Mezzapelle
- School of Medicine, Università Vita e Salute-San Raffaele, Milan, Italy
- Chromatin Dynamics Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Tim Schulte
- Institute of Molecular and Translational Cardiology, IRCCS Policlinico San Donato, Milan, Italy
| | - Chiara Zucchelli
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Chiara Pastorello
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Camilla Carmeno
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Francesca Caprioglio
- School of Medicine, Università Vita e Salute-San Raffaele, Milan, Italy
- Chromatin Dynamics Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Stefano Ricagno
- Institute of Molecular and Translational Cardiology, IRCCS Policlinico San Donato, Milan, Italy
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Gabriele Giachin
- Department of Chemical Sciences (DiSC), University of Padua, 35131, Padova, Italy
| | - Michela Ghitti
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy.
| | - Marco Emilio Bianchi
- School of Medicine, Università Vita e Salute-San Raffaele, Milan, Italy
- Chromatin Dynamics Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Giovanna Musco
- Biomolecular NMR Laboratory, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, Milan, Italy.
| |
Collapse
|
6
|
Kessler N, Akabayov SR, Cohen LS, Scherf T, Naider F, Anglister J. The chemokines CCL5 and CXCL12 exhibit high-affinity binding to N-terminal peptides of the non-cognate receptors CXCR4 and CCR5, respectively. FEBS J 2024; 291:458-476. [PMID: 37997026 DOI: 10.1111/febs.17013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/16/2023] [Accepted: 11/21/2023] [Indexed: 11/25/2023]
Abstract
CC and CXC chemokines are distinct chemokine subfamilies. CC chemokines usually do not bind CXC-chemokine receptors and vice versa. CCR5 and CXCR4 receptors are activated by CCL5 and CXCL12 chemokines, respectively, and are also used as HIV-1 coreceptors. CCL5 contains one conserved binding site for a sulfated tyrosine residue, whereas CXCL12 is unique in having two additional sites for sulfated/nonsulfated tyrosine residues. In this study, N-terminal (Nt) CXCR4 peptides were found to bind CCL5 with somewhat higher affinities in comparison to those of short Nt-CCR5(8-20) peptides with the same number of sulfated tyrosine residues. Similarly, a long Nt-CCR5(1-27)(s Y3,s Y10,s Y14) peptide cross reacts with CXCL12 and with lower KD in comparison to its binding to CCL5. Intermolecular nuclear overhauser effect (NOE) measurements were used to decipher the mechanism of the chemokine/Nt-receptor peptide binding. The Nt-CXCR4 peptides interact with the conserved CCL5 tyrosine sulfate-binding site by an allovalency mechanism like that observed for CCL5 binding of Nt-CCR5 peptides. Nt-CCR5 peptides bind CXCL12 in multiple modes analogous to their binding to HIV-1 gp120 and interact with all three tyrosine/sulfated tyrosine-binding pockets of CXCL12. We suggest that the chemokine-receptors Nt-segments bind promiscuously to cognate and non-cognate chemokines and in a mechanism that is dependent on the number of binding pockets for tyrosine residues found on the chemokine. In conclusion, common features shared among the chemokine-receptors' Nt-segments such as multiple tyrosine residues that are potentially sulfated, and a large number of negatively charged residues are the reason of the cross binding observed in this study.
Collapse
Affiliation(s)
- Naama Kessler
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Sabine R Akabayov
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Leah S Cohen
- Department of Chemistry and Macromolecular Assembly Institute, College of Staten Island of the City University of New York, Staten Island, NY, USA
- The Ph.D. Programs in Biochemistry and Chemistry, The Graduate Center of the City University of New York, NY, USA
| | - Tali Scherf
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Fred Naider
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
- Department of Chemistry and Macromolecular Assembly Institute, College of Staten Island of the City University of New York, Staten Island, NY, USA
- The Ph.D. Programs in Biochemistry and Chemistry, The Graduate Center of the City University of New York, NY, USA
| | - Jacob Anglister
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
7
|
Vales S, Kryukova J, Chandra S, Smagurauskaite G, Payne M, Clark CJ, Hafner K, Mburu P, Denisov S, Davies G, Outeiral C, Deane CM, Morris GM, Bhattacharya S. Discovery and pharmacophoric characterization of chemokine network inhibitors using phage-display, saturation mutagenesis and computational modelling. Nat Commun 2023; 14:5763. [PMID: 37717048 PMCID: PMC10505172 DOI: 10.1038/s41467-023-41488-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 09/06/2023] [Indexed: 09/18/2023] Open
Abstract
CC and CXC-chemokines are the primary drivers of chemotaxis in inflammation, but chemokine network redundancy thwarts pharmacological intervention. Tick evasins promiscuously bind CC and CXC-chemokines, overcoming redundancy. Here we show that short peptides that promiscuously bind both chemokine classes can be identified from evasins by phage-display screening performed with multiple chemokines in parallel. We identify two conserved motifs within these peptides and show using saturation-mutagenesis phage-display and chemotaxis studies of an exemplar peptide that an anionic patch in the first motif and hydrophobic, aromatic and cysteine residues in the second are functionally necessary. AlphaFold2-Multimer modelling suggests that the peptide occludes distinct receptor-binding regions in CC and in CXC-chemokines, with the first and second motifs contributing ionic and hydrophobic interactions respectively. Our results indicate that peptides with broad-spectrum anti-chemokine activity and therapeutic potential may be identified from evasins, and the pharmacophore characterised by phage display, saturation mutagenesis and computational modelling.
Collapse
Affiliation(s)
- Serena Vales
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Jhanna Kryukova
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Soumyanetra Chandra
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Gintare Smagurauskaite
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Megan Payne
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Charlie J Clark
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Katrin Hafner
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Philomena Mburu
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Stepan Denisov
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Graham Davies
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Carlos Outeiral
- Department of Statistics, University of Oxford, 24-29 St Giles, Oxford, OX1 3LB, UK
| | - Charlotte M Deane
- Department of Statistics, University of Oxford, 24-29 St Giles, Oxford, OX1 3LB, UK
| | - Garrett M Morris
- Department of Statistics, University of Oxford, 24-29 St Giles, Oxford, OX1 3LB, UK
| | - Shoumo Bhattacharya
- Wellcome Centre for Human Genetics and RDM Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK.
| |
Collapse
|
8
|
Pawnikar S, Akhter S, Miao Y. Structural dynamics of chemokine receptors. VITAMINS AND HORMONES 2023; 123:645-662. [PMID: 37718001 DOI: 10.1016/bs.vh.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Membrane proteins such as G protein-coupled receptors (GPCRs) are involved in awide range of physiological and pathological cellular processes. Binding of extracellular signals to GPCRs, including hormones, neurotransmitters, peptides and proteins, can activate intracellular signaling cascades via G protein interaction. Chemokine receptors are key GPCRs implicated in cancers, immune responses, cell migration and inflammation. Specifically, the CCR5 and CXCR4 chemokine receptors serve as important therapeutic targets against Human Immunodeficiency virus (HIV) entry into human cells. Maraviroc and Vicriviroc, two clinically used HIV entry inhibitors, are antagonists of the CCR5 receptor. These drugs block HIV entry, but ultimately resistance develops, due to emergence of viruses that can utilize the CXCR4 co-receptor. Unfortunately, development of chemokine receptor antagonists as selective drugs of HIV infection has been greatly hindered as their target orthosteric site is conserved among different receptor subtypes. Accordingly, it is important to understand the structural dynamics of these receptors to develop more effective therapeutics. In this chapter, we describe the latest advances in studies of these two key chemokine receptors with respect to their structures, dynamics and function.
Collapse
Affiliation(s)
- Shristi Pawnikar
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, United States
| | - Sana Akhter
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, United States
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, United States.
| |
Collapse
|
9
|
Jefferson RE, Oggier A, Füglistaler A, Camviel N, Hijazi M, Villarreal AR, Arber C, Barth P. Computational design of dynamic receptor-peptide signaling complexes applied to chemotaxis. Nat Commun 2023; 14:2875. [PMID: 37208363 DOI: 10.1038/s41467-023-38491-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 05/04/2023] [Indexed: 05/21/2023] Open
Abstract
Engineering protein biosensors that sensitively respond to specific biomolecules by triggering precise cellular responses is a major goal of diagnostics and synthetic cell biology. Previous biosensor designs have largely relied on binding structurally well-defined molecules. In contrast, approaches that couple the sensing of flexible compounds to intended cellular responses would greatly expand potential biosensor applications. Here, to address these challenges, we develop a computational strategy for designing signaling complexes between conformationally dynamic proteins and peptides. To demonstrate the power of the approach, we create ultrasensitive chemotactic receptor-peptide pairs capable of eliciting potent signaling responses and strong chemotaxis in primary human T cells. Unlike traditional approaches that engineer static binding complexes, our dynamic structure design strategy optimizes contacts with multiple binding and allosteric sites accessible through dynamic conformational ensembles to achieve strongly enhanced signaling efficacy and potency. Our study suggests that a conformationally adaptable binding interface coupled to a robust allosteric transmission region is a key evolutionary determinant of peptidergic GPCR signaling systems. The approach lays a foundation for designing peptide-sensing receptors and signaling peptide ligands for basic and therapeutic applications.
Collapse
Affiliation(s)
- Robert E Jefferson
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
| | - Aurélien Oggier
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
| | - Andreas Füglistaler
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
| | - Nicolas Camviel
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
- Department of Oncology UNIL-CHUV, University Hospital Lausanne (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Mahdi Hijazi
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
| | - Ana Rico Villarreal
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
| | - Caroline Arber
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland
- Department of Oncology UNIL-CHUV, University Hospital Lausanne (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Patrick Barth
- Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland.
- Ludwig Institute for Cancer Research Lausanne, Lausanne, Switzerland.
| |
Collapse
|
10
|
Deng K, Lin S, Xu Z, Qin J, Yuan L, Sun Y, Wei J, Zheng T, Zheng Z, Qin F, Li S. A novel gene signature derived from the CXC subfamily of chemokine receptors predicts the prognosis and immune infiltration of patients with lung adenocarcinoma. Medicine (Baltimore) 2022; 101:e30982. [PMID: 36254009 PMCID: PMC9575749 DOI: 10.1097/md.0000000000030982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The highly malignant nature of lung adenocarcinoma (LUAD) makes its early diagnosis and prognostic assessment particularly important. However, whether the CXC subfamily of chemokine receptors (CXCR) is involved in the development and prognosis of LUAD remains unclear. Here, differentially expressed genes (DEGs) associated with overall survival (OS) were selected from the cancer genome atlas (TCGA) dataset using univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) regression analysis. Then, a prognostic gene signature was constructed, which was evaluated using Kaplan-Meier curves, receiver operating characteristics curves, nomogram curves, and an external gene expression omnibus (GEO) dataset. Finally, we verified the functions of the genes comprising the signature using the gene expression profiling interactive analysis (GEPIA) and the immune system interaction database (TISIDB) web portals. We constructed a 7-gene signature (SHC1, PRKCD, VEGFC, RPS6KA1, CAT, CDC25C, and GPI) that stratified patients into high- and low-risk categories. Notably, the risk score of the signature was a separate and effective predictor for OS (P < .001). Patients in the low-risk category had a better prognosis than those in the high-risk category. The receiver operating characteristics and nomogram curves verified the predictive power of the signature. Moreover, in both categories, biological processes and pathways associated with cell migration were enriched. Immune infiltration statuses differed between the 2 risk categories. Critically, the results from the GEPIA and TISIDB web portals indicated that the expression of the 7-gene signature was associated with survival, clinical stage, and immune subtypes of LUAD patients. We identified a CXCR-related gene signature that could assess prognosis and provide a reference for the diagnosis and treatment of LUAD.
Collapse
Affiliation(s)
- Kun Deng
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Shenghua Lin
- Department of Thoracic and Cardiovascular Surgery,The People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Zhanyu Xu
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Junqi Qin
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Liqiang Yuan
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Yu Sun
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Jiangbo Wei
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Tiaozhan Zheng
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Zhiwen Zheng
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
| | - Fanglu Qin
- Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
- *Correspondence: Shikang Li, Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region 530021, P. R. China (e-mail: )
| | - Shikang Li
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, P. R. China
- *Correspondence: Shikang Li, Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region 530021, P. R. China (e-mail: )
| |
Collapse
|
11
|
Yen YC, Schafer CT, Gustavsson M, Eberle SA, Dominik PK, Deneka D, Zhang P, Schall TJ, Kossiakoff AA, Tesmer JJG, Handel TM. Structures of atypical chemokine receptor 3 reveal the basis for its promiscuity and signaling bias. SCIENCE ADVANCES 2022; 8:eabn8063. [PMID: 35857509 PMCID: PMC9278869 DOI: 10.1126/sciadv.abn8063] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 05/26/2022] [Indexed: 05/12/2023]
Abstract
Both CXC chemokine receptor 4 (CXCR4) and atypical chemokine receptor 3 (ACKR3) are activated by the chemokine CXCL12 yet evoke distinct cellular responses. CXCR4 is a canonical G protein-coupled receptor (GPCR), whereas ACKR3 is intrinsically biased for arrestin. The molecular basis for this difference is not understood. Here, we describe cryo-EM structures of ACKR3 in complex with CXCL12, a more potent CXCL12 variant, and a small-molecule agonist. The bound chemokines adopt an unexpected pose relative to those established for CXCR4 and observed in other receptor-chemokine complexes. Along with functional studies, these structures provide insight into the ligand-binding promiscuity of ACKR3, why it fails to couple to G proteins, and its bias toward β-arrestin. The results lay the groundwork for understanding the physiological interplay of ACKR3 with other GPCRs.
Collapse
Affiliation(s)
- Yu-Chen Yen
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Christopher T. Schafer
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Martin Gustavsson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Stefanie A. Eberle
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Pawel K. Dominik
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Dawid Deneka
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Department of Biophysics, Jagiellonian University, Krakow, Poland
| | - Penglie Zhang
- ChemoCentryx Inc., 835 Industrial Rd., Suite 600, San Carlos, CA 94070, USA
| | - Thomas J. Schall
- ChemoCentryx Inc., 835 Industrial Rd., Suite 600, San Carlos, CA 94070, USA
| | - Anthony A. Kossiakoff
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - John J. G. Tesmer
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
- Department of Molecular Pharmacology and Medicinal Chemistry, Purdue University, West Lafayette, IN, USA
| | - Tracy M. Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| |
Collapse
|
12
|
Allosteric modulation of the chemokine receptor-chemokine CXCR4-CXCL12 complex by tyrosine sulfation. Int J Biol Macromol 2022; 206:812-822. [PMID: 35306016 DOI: 10.1016/j.ijbiomac.2022.03.078] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/03/2022] [Accepted: 03/13/2022] [Indexed: 11/21/2022]
Abstract
The chemokine receptor CXCR4 and its cognate ligand CXCL12 mediate pathways that lead to cell migration and chemotaxis. Although the structural details of related receptor-ligand complexes have been resolved, the roles of the N-terminal domain of the receptor and post-translational sulfation that are determinants of ligand selectivity and affinity remain unclear. Here, we analyze the structural dynamics induced by receptor sulfation by combining molecular dynamics, docking and network analysis. The sulfotyrosine residues, 7YsN-term, 12YsN-term and 21YsN-term allow the N-terminal domain of the apo-sulfated receptor to adopt an "open" conformation that appears to facilitate ligand binding. The overall topology of the CXCR4-CXCL12 complex is independent of the sulfation state, but an extensive network of protein-protein interactions characterizes the sulfated receptor, in line with its increased ligand affinity. The altered interactions of sulfotyrosine residues, such as 21YsN-term-47RCXCL12 replacing the 21YN-term-13FCXCL12 interaction, propagate via allosteric pathways towards the receptor lumen. In particular, our results suggest that the experimentally-reported receptor-ligand interactions 262D6.58-8RCXCL12 and 277E7.28-12RCXCL12 could be dependent on the sulfation state of the receptor and need to be carefully analyzed. Our work is an important step in understanding chemokine-receptor interactions and how post-translational modifications could modulate receptor-ligand complexes.
Collapse
|
13
|
Pawnikar S, Miao Y. Mechanism of Peptide Agonist Binding in CXCR4 Chemokine Receptor. Front Mol Biosci 2022; 9:821055. [PMID: 35359589 PMCID: PMC8963245 DOI: 10.3389/fmolb.2022.821055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/14/2022] [Indexed: 01/07/2023] Open
Abstract
Chemokine receptors are key G-protein-coupled receptors (GPCRs) that control cell migration in immune system responses, development of cardiovascular and central nervous systems, and numerous diseases. In particular, the CXCR4 chemokine receptor promotes metastasis, tumor growth and angiogenesis in cancers. CXCR4 is also used as one of the two co-receptors for T-tropic HIV-1 entry into host cells. Therefore, CXCR4 serves as an important therapeutic target for treating cancers and HIV infection. Apart from the CXCL12 endogenous peptide agonist, previous studies suggested that the first 17 amino acids of CXCL12 are sufficient to activate CXCR4. Two 17-residue peptides with positions 1-4 mutated to RSVM and ASLW functioned as super and partial agonists of CXCR4, respectively. However, the mechanism of peptide agonist binding in CXCR4 remains unclear. Here, we have investigated this mechanism through all-atom simulations using a novel Peptide Gaussian accelerated molecular dynamics (Pep-GaMD) method. The Pep-GaMD simulations have allowed us to explore representative binding conformations of each peptide and identify critical low-energy states of CXCR4 activated by the super versus partial peptide agonists. Our simulations have provided important mechanistic insights into peptide agonist binding in CXCR4, which are expected to facilitate rational design of new peptide modulators of CXCR4 and other chemokine receptors.
Collapse
|
14
|
Jørgensen AS, Daugvilaite V, De Filippo K, Berg C, Mavri M, Benned-Jensen T, Juzenaite G, Hjortø G, Rankin S, Våbenø J, Rosenkilde MM. Biased action of the CXCR4-targeting drug plerixafor is essential for its superior hematopoietic stem cell mobilization. Commun Biol 2021; 4:569. [PMID: 33980979 PMCID: PMC8115334 DOI: 10.1038/s42003-021-02070-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 03/31/2021] [Indexed: 01/14/2023] Open
Abstract
Following the FDA-approval of the hematopoietic stem cell (HSC) mobilizer plerixafor, orally available and potent CXCR4 antagonists were pursued. One such proposition was AMD11070, which was orally active and had superior antagonism in vitro; however, it did not appear as effective for HSC mobilization in vivo. Here we show that while AMD11070 acts as a full antagonist, plerixafor acts biased by stimulating β-arrestin recruitment while fully antagonizing G protein. Consequently, while AMD11070 prevents the constitutive receptor internalization, plerixafor allows it and thereby decreases receptor expression. These findings are confirmed by the successful transfer of both ligands' binding sites and action to the related CXCR3 receptor. In vivo, plerixafor exhibits superior HSC mobilization associated with a dramatic reversal of the CXCL12 gradient across the bone marrow endothelium, which is not seen for AMD11070. We propose that the biased action of plerixafor is central for its superior therapeutic effect in HSC mobilization.
Collapse
Affiliation(s)
- Astrid S Jørgensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Viktorija Daugvilaite
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Katia De Filippo
- Department of Medicine, National Heart and Lung Institute (NHLI), Imperial College, London, United Kingdom
| | - Christian Berg
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Unit for Infectious Diseases, Department of Medicine, Herlev-Gentofte Hospital, University of Copenhagen, Herlev, Denmark
| | - Masa Mavri
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Tau Benned-Jensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- Lundbeck A/S, Copenhagen, Denmark
| | - Goda Juzenaite
- Department of Medicine, National Heart and Lung Institute (NHLI), Imperial College, London, United Kingdom
| | - Gertrud Hjortø
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Sara Rankin
- Department of Medicine, National Heart and Lung Institute (NHLI), Imperial College, London, United Kingdom
| | - Jon Våbenø
- Helgeland Hospital Trust, Sandnessjøen, Norway.
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
15
|
Kline JM, Heusinkveld LE, Taranto E, Martin CB, Tomasi AG, Hsu IJ, Cho K, Khillan JS, Murphy PM, Pontejo SM. Structural and functional analysis of Ccr1l1, a Rodentia-restricted eosinophil-selective chemokine receptor homologue. J Biol Chem 2021; 296:100373. [PMID: 33548230 PMCID: PMC7949164 DOI: 10.1016/j.jbc.2021.100373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/26/2021] [Accepted: 02/01/2021] [Indexed: 11/25/2022] Open
Abstract
Mouse Ccr1l1 (Ccr1-like 1) encodes an orphan G-protein-coupled receptor (GPCR) with the highest homology to the inflammatory and highly promiscuous chemokine receptors Ccr1 and Ccr3 (70 and 50% amino acid identity, respectively). Ccr1l1 was first cloned in 1995, yet current knowledge of this putative chemokine receptor is limited to its gene organization and chromosomal localization. Here we report that Ccr1l1 is a Rodentia-specific gene selectively expressed in eosinophils. However, eosinophil phenotypes, development, and responsiveness to chemokines were all normal in naïve Ccr1l1 knockout mice. We demonstrate for the first time that recombinant Ccr1l1 is expressed on the plasma membrane of transfected cells and contains an extracellular N terminus and an intracellular C terminus, consistent with GPCR topology. Using receptor internalization, β-arrestin recruitment, calcium flux, and chemotaxis assays, we excluded all 37 available mouse chemokines, including Ccr1 ligands, and two viral chemokines as Ccr1l1 ligands, and demonstrated that mouse Ccr1, but not Ccr1l1, exhibits constitutive signaling activity. However, sequence analysis and structural modeling revealed that Ccr1l1 is well equipped to act as a classical signaling GPCR, with N-terminal sulfotyrosines as the only signaling and chemokine-binding determinant absent in Ccr1l1. Hereof, we show that a sulfatable N-terminal Ccr1 Y18 residue is essential for chemotaxis and calcium responses induced by Ccl3 and Ccl9/10, but substituting the corresponding Ccr1l1 F19 residue with tyrosine failed to confer responsiveness to Ccr1 ligands. Although Ccr1l1 remains an extreme outlier in the chemokine receptor family, our study supports that it might respond to unidentified mouse chemokine ligands in eosinophil-driven immune responses.
Collapse
Affiliation(s)
- Jaclyn M Kline
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Lauren E Heusinkveld
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Eleanor Taranto
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Clare B Martin
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Alessandra G Tomasi
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Isabel J Hsu
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Kyoungin Cho
- Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jaspal S Khillan
- Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Philip M Murphy
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Sergio M Pontejo
- Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
| |
Collapse
|
16
|
Eiger DS, Boldizsar N, Honeycutt CC, Gardner J, Rajagopal S. Biased agonism at chemokine receptors. Cell Signal 2020; 78:109862. [PMID: 33249087 DOI: 10.1016/j.cellsig.2020.109862] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/07/2020] [Accepted: 11/24/2020] [Indexed: 12/11/2022]
Abstract
In the human chemokine system, interactions between the approximately 50 known endogenous chemokine ligands and 20 known chemokine receptors (CKRs) regulate a wide range of cellular functions and biological processes including immune cell activation and homeostasis, development, angiogenesis, and neuromodulation. CKRs are a family of G protein-coupled receptors (GPCR), which represent the most common and versatile class of receptors in the human genome and the targets of approximately one third of all Food and Drug Administration-approved drugs. Chemokines and CKRs bind with significant promiscuity, as most CKRs can be activated by multiple chemokines and most chemokines can activate multiple CKRs. While these ligand-receptor interactions were previously regarded as redundant, it is now appreciated that many chemokine:CKR interactions display biased agonism, the phenomenon in which different ligands binding to the same receptor signal through different pathways with different efficacies, leading to distinct biological effects. Notably, these biased responses can be modulated through changes in ligand, receptor, and or the specific cellular context (system). In this review, we explore the biochemical mechanisms, functional consequences, and therapeutic potential of biased agonism in the chemokine system. An enhanced understanding of biased agonism in the chemokine system may prove transformative in the understanding of the mechanisms and consequences of biased signaling across all GPCR subtypes and aid in the development of biased pharmaceuticals with increased therapeutic efficacy and safer side effect profiles.
Collapse
Affiliation(s)
| | - Noelia Boldizsar
- Trinity College of Arts and Sciences, Duke University, Durham, NC 27710, USA.
| | | | - Julia Gardner
- Trinity College of Arts and Sciences, Duke University, Durham, NC 27710, USA.
| | - Sudarshan Rajagopal
- Department of Biochemistry, Duke University, Durham, NC 27710, USA; Department of Medicine, Duke University, Durham, NC 27710, USA.
| |
Collapse
|
17
|
Advanced fluorescence microscopy reveals disruption of dynamic CXCR4 dimerization by subpocket-specific inverse agonists. Proc Natl Acad Sci U S A 2020; 117:29144-29154. [PMID: 33148803 PMCID: PMC7682396 DOI: 10.1073/pnas.2013319117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Class A G protein−coupled receptors (GPCRs) can form dimers and oligomers via poorly understood mechanisms. We show here that the chemokine receptor CXCR4, which is a major pharmacological target, has an oligomerization behavior modulated by its active conformation. Combining advanced, single-molecule, and single-cell optical tools with functional assays and computational approaches, we unveil three key features of CXCR4 quaternary organization: CXCR4 dimerization 1) is dynamic, 2) increases with receptor expression level, and 3) can be disrupted by stabilizing an inactive receptor conformation. Ligand binding motifs reveal a ligand binding subpocket essential to modulate both CXCR4 basal activity and dimerization. This is relevant to develop new strategies to design CXCR4-targeting drugs. Although class A G protein−coupled receptors (GPCRs) can function as monomers, many of them form dimers and oligomers, but the mechanisms and functional relevance of such oligomerization is ill understood. Here, we investigate this problem for the CXC chemokine receptor 4 (CXCR4), a GPCR that regulates immune and hematopoietic cell trafficking, and a major drug target in cancer therapy. We combine single-molecule microscopy and fluorescence fluctuation spectroscopy to investigate CXCR4 membrane organization in living cells at densities ranging from a few molecules to hundreds of molecules per square micrometer of the plasma membrane. We observe that CXCR4 forms dynamic, transient homodimers, and that the monomer−dimer equilibrium is governed by receptor density. CXCR4 inverse agonists that bind to the receptor minor pocket inhibit CXCR4 constitutive activity and abolish receptor dimerization. A mutation in the minor binding pocket reduced the dimer-disrupting ability of these ligands. In addition, mutating critical residues in the sixth transmembrane helix of CXCR4 markedly diminished both basal activity and dimerization, supporting the notion that CXCR4 basal activity is required for dimer formation. Together, these results link CXCR4 dimerization to its density and to its activity. They further suggest that inverse agonists binding to the minor pocket suppress both dimerization and constitutive activity and may represent a specific strategy to target CXCR4.
Collapse
|
18
|
Capturing Peptide-GPCR Interactions and Their Dynamics. Molecules 2020; 25:molecules25204724. [PMID: 33076289 PMCID: PMC7587574 DOI: 10.3390/molecules25204724] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 12/16/2022] Open
Abstract
Many biological functions of peptides are mediated through G protein-coupled receptors (GPCRs). Upon ligand binding, GPCRs undergo conformational changes that facilitate the binding and activation of multiple effectors. GPCRs regulate nearly all physiological processes and are a favorite pharmacological target. In particular, drugs are sought after that elicit the recruitment of selected effectors only (biased ligands). Understanding how ligands bind to GPCRs and which conformational changes they induce is a fundamental step toward the development of more efficient and specific drugs. Moreover, it is emerging that the dynamic of the ligand–receptor interaction contributes to the specificity of both ligand recognition and effector recruitment, an aspect that is missing in structural snapshots from crystallography. We describe here biochemical and biophysical techniques to address ligand–receptor interactions in their structural and dynamic aspects, which include mutagenesis, crosslinking, spectroscopic techniques, and mass-spectrometry profiling. With a main focus on peptide receptors, we present methods to unveil the ligand–receptor contact interface and methods that address conformational changes both in the ligand and the GPCR. The presented studies highlight a wide structural heterogeneity among peptide receptors, reveal distinct structural changes occurring during ligand binding and a surprisingly high dynamics of the ligand–GPCR complexes.
Collapse
|
19
|
Wedemeyer MJ, Mahn SA, Getschman AE, Crawford KS, Peterson FC, Marchese A, McCorvy JD, Volkman BF. The chemokine X-factor: Structure-function analysis of the CXC motif at CXCR4 and ACKR3. J Biol Chem 2020; 295:13927-13939. [PMID: 32788219 DOI: 10.1074/jbc.ra120.014244] [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] [Received: 05/10/2020] [Revised: 07/31/2020] [Indexed: 11/06/2022] Open
Abstract
The human chemokine family consists of 46 protein ligands that induce chemotactic cell migration by activating a family of 23 G protein-coupled receptors. The two major chemokine subfamilies, CC and CXC, bind distinct receptor subsets. A sequence motif defining these families, the X position in the CXC motif, is not predicted to make significant contacts with the receptor, but instead links structural elements associated with binding and activation. Here, we use comparative analysis of chemokine NMR structures, structural modeling, and molecular dynamic simulations that suggested the X position reorients the chemokine N terminus. Using CXCL12 as a model CXC chemokine, deletion of the X residue (Pro-10) had little to no impact on the folded chemokine structure but diminished CXCR4 agonist activity as measured by ERK phosphorylation, chemotaxis, and Gi/o-mediated cAMP inhibition. Functional impairment was attributed to over 100-fold loss of CXCR4 binding affinity. Binding to the other CXCL12 receptor, ACKR3, was diminished nearly 500-fold. Deletion of Pro-10 had little effect on CXCL12 binding to the CXCR4 N terminus, a major component of the chemokine-GPCR interface. Replacement of the X residue with the most frequent amino acid at this position (P10Q) had an intermediate effect between WT and P10del in each assay, with ACKR3 having a higher tolerance for this mutation. This work shows that the X residue helps to position the CXCL12 N terminus for optimal docking into the orthosteric pocket of CXCR4 and suggests that the CC/CXC motif contributes directly to receptor selectivity by orienting the chemokine N terminus in a subfamily-specific direction.
Collapse
Affiliation(s)
- Michael J Wedemeyer
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Sarah A Mahn
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Anthony E Getschman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Kyler S Crawford
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Francis C Peterson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Adriano Marchese
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - John D McCorvy
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
| |
Collapse
|
20
|
Aguilera-Durán G, Romo-Mancillas A. Computational Study of C-X-C Chemokine Receptor (CXCR)3 Binding with Its Natural Agonists Chemokine (C-X-C Motif) Ligand (CXCL)9, 10 and 11 and with Synthetic Antagonists: Insights of Receptor Activation towards Drug Design for Vitiligo. Molecules 2020; 25:E4413. [PMID: 32992956 PMCID: PMC7582348 DOI: 10.3390/molecules25194413] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/21/2020] [Accepted: 09/23/2020] [Indexed: 12/31/2022] Open
Abstract
Vitiligo is a hypopigmentary skin pathology resulting from the death of melanocytes due to the activity of CD8+ cytotoxic lymphocytes and overexpression of chemokines. These include CXCL9, CXCL10, and CXCL11 and its receptor CXCR3, both in peripheral cells of the immune system and in the skin of patients diagnosed with vitiligo. The three-dimensional structure of CXCR3 and CXCL9 has not been reported experimentally; thus, homology modeling and molecular dynamics could be useful for the study of this chemotaxis-promoter axis. In this work, a homology model of CXCR3 and CXCL9 and the structure of the CXCR3/Gαi/0βγ complex with post-translational modifications of CXCR3 are reported for the study of the interaction of chemokines with CXCR3 through all-atom (AA-MD) and coarse-grained molecular dynamics (CG-MD) simulations. AA-MD and CG-MD simulations showed the first activation step of the CXCR3 receptor with all chemokines and the second activation step in the CXCR3-CXCL10 complex through a decrease in the distance between the chemokine and the transmembrane region of CXCR3 and the separation of the βγ complex from the α subunit in the G-protein. Additionally, a general protein-ligand interaction model was calculated, based on known antagonists binding to CXCR3. These results contribute to understanding the activation mechanism of CXCR3 and the design of new molecules that inhibit chemokine binding or antagonize the receptor, provoking a decrease of chemotaxis caused by the CXCR3/chemokines axis.
Collapse
Affiliation(s)
- Giovanny Aguilera-Durán
- Posgrado en Ciencias Químico Biológicas, Facultad de Química, Universidad Autónoma de Querétaro, Cerro de las Campanas S/N, Querétaro 76010, Mexico;
- Laboratorio de Diseño Asistido por Computadora y Síntesis de Fármacos, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico
| | - Antonio Romo-Mancillas
- Laboratorio de Diseño Asistido por Computadora y Síntesis de Fármacos, Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico
| |
Collapse
|
21
|
Stephens BS, Ngo T, Kufareva I, Handel TM. Functional anatomy of the full-length CXCR4-CXCL12 complex systematically dissected by quantitative model-guided mutagenesis. Sci Signal 2020; 13:eaay5024. [PMID: 32665413 PMCID: PMC7437921 DOI: 10.1126/scisignal.aay5024] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Because of their prominent roles in development, cancer, and HIV, the chemokine receptor CXCR4 and its ligand CXCL12 have been the subject of numerous structural and functional studies, but the determinants of ligand binding, selectivity, and signaling are still poorly understood. Here, building on our latest structural model, we used a systematic mutagenesis strategy to dissect the functional anatomy of the CXCR4-CXCL12 complex. Key charge swap mutagenesis experiments provided evidence for pairwise interactions between oppositely charged residues in the receptor and chemokine, confirming the accuracy of the predicted orientation of the chemokine relative to the receptor and providing insight into ligand selectivity. Progressive deletion of N-terminal residues revealed an unexpected contribution of the receptor N terminus to chemokine signaling. This finding challenges a longstanding "two-site" hypothesis about the essential features of the receptor-chemokine interaction in which the N terminus contributes only to binding affinity. Our results suggest that although the interaction of the chemokine N terminus with the receptor-binding pocket is the key driver of signaling, the signaling amplitude depends on the extent to which the receptor N terminus binds the chemokine. Together with systematic characterization of other epitopes, these data enable us to propose an experimentally consistent structural model for how CXCL12 binds CXCR4 and initiates signal transmission through the receptor transmembrane domain.
Collapse
Affiliation(s)
- Bryan S Stephens
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Tony Ngo
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA.
| | - Tracy M Handel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
22
|
Liu K, Wu L, Yuan S, Wu M, Xu Y, Sun Q, Li S, Zhao S, Hua T, Liu ZJ. Structural basis of CXC chemokine receptor 2 activation and signalling. Nature 2020; 585:135-140. [PMID: 32610344 DOI: 10.1038/s41586-020-2492-5] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 05/14/2020] [Indexed: 01/25/2023]
Abstract
Chemokines and their receptors mediate cell migration, which influences multiple fundamental biological processes and disease conditions such as inflammation and cancer1. Although ample effort has been invested into the structural investigation of the chemokine receptors and receptor-chemokine recognition2-4, less is known about endogenous chemokine-induced receptor activation and G-protein coupling. Here we present the cryo-electron microscopy structures of interleukin-8 (IL-8, also known as CXCL8)-activated human CXC chemokine receptor 2 (CXCR2) in complex with Gi protein, along with a crystal structure of CXCR2 bound to a designed allosteric antagonist. Our results reveal a unique shallow mode of binding between CXCL8 and CXCR2, and also show the interactions between CXCR2 and Gi protein. Further structural analysis of the inactive and active states of CXCR2 reveals a distinct activation process and the competitive small-molecule antagonism of chemokine receptors. In addition, our results provide insights into how a G-protein-coupled receptor is activated by an endogenous protein molecule, which will assist in the rational development of therapeutics that target the chemokine system for better pharmacological profiles.
Collapse
Affiliation(s)
- Kaiwen Liu
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China.,Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, China
| | - Lijie Wu
- iHuman Institute, ShanghaiTech University, Shanghai, China
| | - Shuguang Yuan
- The Research Center for Computer-aided Drug Discovery, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Meng Wu
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yueming Xu
- iHuman Institute, ShanghaiTech University, Shanghai, China
| | - Qianqian Sun
- iHuman Institute, ShanghaiTech University, Shanghai, China
| | - Shu Li
- The Research Center for Computer-aided Drug Discovery, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Tian Hua
- iHuman Institute, ShanghaiTech University, Shanghai, China.
| | - Zhi-Jie Liu
- iHuman Institute, ShanghaiTech University, Shanghai, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
| |
Collapse
|