1
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Calderón JC, Ibrahim P, Gobbo D, Gervasio FL, Clark T. Determinants of Neutral Antagonism and Inverse Agonism in the β 2-Adrenergic Receptor. J Chem Inf Model 2024; 64:2045-2057. [PMID: 38447156 DOI: 10.1021/acs.jcim.3c01763] [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: 03/08/2024]
Abstract
Free-energy profiles for the activation/deactivation of the β2-adrenergic receptor (ADRB2) with neutral antagonist and inverse agonist ligands have been determined with well-tempered multiple-walker (MW) metadynamics simulations. The inverse agonists carazolol and ICI118551 clearly favor single inactive conformational minima in both the binary and ternary ligand-receptor-G-protein complexes, in accord with the inverse-agonist activity of the ligands. The behavior of neutral antagonists is more complex, as they seem also to affect the recruitment of the G-protein. The results are analyzed in terms of the conformational states of the well-known microswitches that have been proposed as indicators of receptor activity.
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Affiliation(s)
- Jacqueline C Calderón
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstr. 25, 91052 Erlangen, Germany
| | - Passainte Ibrahim
- Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, 04107 Leipzig, Germany
| | - Dorothea Gobbo
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
| | - Francesco Luigi Gervasio
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
- Chemistry Department, University College London, WC1H 0AJ London, United Kingdom
- Swiss Bioinformatics Institute, CH1206 Geneva, Switzerland
| | - Timothy Clark
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstr. 25, 91052 Erlangen, Germany
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2
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Madhu MK, Shewani K, Murarka RK. Biased Signaling in Mutated Variants of β 2-Adrenergic Receptor: Insights from Molecular Dynamics Simulations. J Chem Inf Model 2024; 64:449-469. [PMID: 38194225 DOI: 10.1021/acs.jcim.3c01481] [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: 01/10/2024]
Abstract
The molecular basis of receptor bias in G protein-coupled receptors (GPCRs) caused by mutations that preferentially activate specific intracellular transducers over others remains poorly understood. Two experimentally identified biased variants of β2-adrenergic receptors (β2AR), a prototypical GPCR, are a triple mutant (T68F, Y132A, and Y219A) and a single mutant (Y219A); the former bias the receptor toward the β-arrestin pathway by disfavoring G protein engagement, while the latter induces G protein signaling explicitly due to selection against GPCR kinases (GRKs) that phosphorylate the receptor as a prerequisite of β-arrestin binding. Though rigorous characterizations have revealed functional implications of these mutations, the atomistic origin of the observed transducer selectivity is not clear. In this study, we investigated the allosteric mechanism of receptor bias in β2AR using microseconds of all-atom Gaussian accelerated molecular dynamics (GaMD) simulations. Our observations reveal distinct rearrangements in transmembrane helices, intracellular loop 3, and critical residues R1313.50 and Y3267.53 in the conserved motifs D(E)RY and NPxxY for the mutant receptors, leading to their specific transducer interactions. Moreover, partial dissociation of G protein from the receptor core is observed in the simulations of the triple mutant in contrast to the single mutant and wild-type receptor. The reorganization of allosteric communications from the extracellular agonist BI-167107 to the intracellular receptor-transducer interfaces drives the conformational rearrangements responsible for receptor bias in the single and triple mutants. The molecular insights into receptor bias of β2AR presented here could improve the understanding of biased signaling in GPCRs, potentially opening new avenues for designing novel therapeutics with fewer side-effects and superior efficacy.
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Affiliation(s)
- Midhun K Madhu
- Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal, Madhya Pradesh 462066, India
| | - Kunal Shewani
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal, Madhya Pradesh 462066, India
| | - Rajesh K Murarka
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal, Madhya Pradesh 462066, India
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3
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Vögele M, Zhang BW, Kaindl J, Wang L. Is the Functional Response of a Receptor Determined by the Thermodynamics of Ligand Binding? J Chem Theory Comput 2023; 19:8414-8422. [PMID: 37943175 DOI: 10.1021/acs.jctc.3c00899] [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: 11/10/2023]
Abstract
For an effective drug, strong binding to the target protein is a prerequisite, but it is not enough. To produce a particular functional response, drugs need to either block the proteins' functions or modulate their activities by changing their conformational equilibrium. The binding free energy of a compound to its target is routinely calculated, but the timescales for the protein conformational changes are prohibitively long to be efficiently modeled via physics-based simulations. Thermodynamic principles suggest that the binding free energies of the ligands with different receptor conformations may infer their efficacy. However, this hypothesis has not been thoroughly validated. We present an actionable protocol and a comprehensive study to show that binding thermodynamics provides a strong predictor of the efficacy of a ligand. We apply the absolute binding free energy perturbation method to ligands bound to active and inactive states of eight G protein-coupled receptors and a nuclear receptor and then compare the resulting binding free energies. We find that carefully designed restraints are often necessary to efficiently model the corresponding conformational ensembles for each state. Our method achieves unprecedented performance in classifying ligands as agonists or antagonists across the various investigated receptors, all of which are important drug targets.
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Affiliation(s)
- Martin Vögele
- Schrödinger, Inc., 1540 Broadway 24th Floor, New York, New York 10036, United States
| | - Bin W Zhang
- Schrödinger, Inc., 1540 Broadway 24th Floor, New York, New York 10036, United States
| | - Jonas Kaindl
- Schrödinger GmbH, Glücksteinallee 25, Mannheim 68163, Germany
| | - Lingle Wang
- Schrödinger, Inc., 1540 Broadway 24th Floor, New York, New York 10036, United States
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4
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Calderón JC, Ibrahim P, Gobbo D, Gervasio FL, Clark T. Activation/Deactivation Free-Energy Profiles for the β 2-Adrenergic Receptor: Ligand Modes of Action. J Chem Inf Model 2023; 63:6332-6343. [PMID: 37824365 DOI: 10.1021/acs.jcim.3c00805] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
We use enhanced-sampling simulations with an effective collective variable to study the activation of the β2-adrenergic receptor in the presence of ligands with different efficacy. The free-energy profiles are computed for the ligand-free (apo) receptor and binary (apo-receptor + G-protein α-subunit and receptor + ligand) and ternary complexes. The results are not only compatible with available experiments but also allow unprecedented structural insight into the nature of GPCR conformations along the activation pathway and their role in the activation mechanism. In particular, the simulations reveal an unexpected mode of action of partial agonists such as salmeterol and salbutamol that arises already in the binary complex without the G-protein. Specific differences in the polar interactions with residues in TM5, which are required to stabilize an optimal TM6 conformation that facilitates G-protein binding and receptor activation, play a major role in differentiating them from full agonists.
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Affiliation(s)
- Jacqueline C Calderón
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstraße 25, 91052 Erlangen, Germany
| | - Passainte Ibrahim
- Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, 04109 Leipzig, Germany
| | - Dorothea Gobbo
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
| | - Francesco Luigi Gervasio
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
- Chemistry Department, University College London, WC1H 0AJ London, United Kingdom
- Swiss Bioinformatics Institute, CH1206 Geneva, Switzerland
| | - Timothy Clark
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstraße 25, 91052 Erlangen, Germany
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5
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Bitsi S, El Eid L, Manchanda Y, Oqua AI, Mohamed N, Hansen B, Suba K, Rutter GA, Salem V, Jones B, Tomas A. Divergent acute versus prolonged pharmacological GLP-1R responses in adult β cell-specific β-arrestin 2 knockout mice. SCIENCE ADVANCES 2023; 9:eadf7737. [PMID: 37134170 PMCID: PMC10156113 DOI: 10.1126/sciadv.adf7737] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 04/04/2023] [Indexed: 05/05/2023]
Abstract
The glucagon-like peptide-1 receptor (GLP-1R) is a major type 2 diabetes therapeutic target. Stimulated GLP-1Rs are rapidly desensitized by β-arrestins, scaffolding proteins that not only terminate G protein interactions but also act as independent signaling mediators. Here, we have assessed in vivo glycemic responses to the pharmacological GLP-1R agonist exendin-4 in adult β cell-specific β-arrestin 2 knockout (KO) mice. KOs displayed a sex-dimorphic phenotype consisting of weaker acute responses that improved 6 hours after agonist injection. Similar effects were observed for semaglutide and tirzepatide but not with biased agonist exendin-phe1. Acute cyclic adenosine 5'-monophosphate increases were impaired, but desensitization reduced in KO islets. The former defect was attributed to enhanced β-arrestin 1 and phosphodiesterase 4 activities, while reduced desensitization co-occurred with impaired GLP-1R recycling and lysosomal targeting, increased trans-Golgi network signaling, and reduced GLP-1R ubiquitination. This study has unveiled fundamental aspects of GLP-1R response regulation with direct application to the rational design of GLP-1R-targeting therapeutics.
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Affiliation(s)
- Stavroula Bitsi
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Liliane El Eid
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Yusman Manchanda
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Affiong I. Oqua
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Nimco Mohamed
- Department of Bioengineering, Imperial College London, London, UK
| | - Ben Hansen
- Department of Bioengineering, Imperial College London, London, UK
| | - Kinga Suba
- Department of Bioengineering, Imperial College London, London, UK
| | - Guy A. Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- CHUM Research Centre, Faculty of Medicine, University of Montreal, Quebec H2X 0A9, Canada
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 637553, Singapore
| | - Victoria Salem
- Department of Bioengineering, Imperial College London, London, UK
| | - Ben Jones
- Section of Endocrinology and Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| | - Alejandra Tomas
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
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6
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Chen X, Yuan Y, Chen Y, Yu J, Wang J, Chen J, Guo Y, Pu X. Biased Activation Mechanism Induced by GPCR Heterodimerization: Observations from μOR/δOR Dimers. J Chem Inf Model 2022; 62:5581-5600. [PMID: 36377848 DOI: 10.1021/acs.jcim.2c00962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
GPCRs regulate multiple intracellular signaling cascades. Biasedly activating one signaling pathway over the others provides additional clinical utility to optimize GPCR-based therapies. GPCR heterodimers possess different functions from their monomeric states, including their selectivity to different transducers. However, the biased signaling mechanism induced by the heterodimerization remains unclear. Motivated by the issue, we select an important GPCR heterodimer (μOR/δOR heterodimer) as a case and use microsecond Gaussian accelerated molecular dynamics simulation coupled with potential of mean force and protein structure network (PSN) to probe mechanisms regarding the heterodimerization-induced constitutive β-arrestin activity and efficacy change of the agonist DAMGO. The results show that only the lowest energy state of the μOR/δOR heterodimer, which adopts a slightly outward shift of TM6 and an ICL2 conformation close to the receptor core, can selectively accommodate β-arrestins. PSN further reveals important roles of H8, ICL1, and ICL2 in regulating the constitutive β-arrestin-biased activity for the apo μOR/δOR heterodimer. In addition, the heterodimerization can allosterically alter the binding mode of DAMGO mainly by means of W7.35. Consequently, DAMGO transmits the structural signal mainly through TM6 and TM7 in the dimer, rather than TM3 similar to the μOR monomer, thus changing the efficacy of DAMGO from a balanced agonist to the β-arrestin-biased one. On the other side, the binding of DAMGO to the heterodimer can stabilize μOR/δOR heterodimers through a stronger interaction of TM1/TM1 and H8/H8, accordingly enhancing the interaction of μOR with δOR and the binding affinity of the dimer to the β-arrestin. The agonist DAMGO does not change main compositions of the regulation network from the dimer interface to the transducer binding pocket of the μOR protomer, but induces an increase in the structural communication of the network, which should contribute to the enhanced β-arrestin coupling. Our observations, for the first time, reveal the molecular mechanism of the biased signaling induced by the heterodimerization for GPCRs, which should be beneficial to more comprehensively understand the GPCR bias signaling.
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Affiliation(s)
- Xin Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu610041, China
| | - Yichi Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Jin Yu
- Department of Physics and Astronomy, University of California, Irvine, California92697, United States
| | - Jingzhou Wang
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Yanzhi Guo
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu610064, China
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7
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In Silico Study of Allosteric Communication Networks in GPCR Signaling Bias. Int J Mol Sci 2022; 23:ijms23147809. [PMID: 35887157 PMCID: PMC9315799 DOI: 10.3390/ijms23147809] [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: 06/22/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 11/20/2022] Open
Abstract
Signaling bias is a promising characteristic of G protein-coupled receptors (GPCRs) as it provides the opportunity to develop more efficacious and safer drugs. This is because biased ligands can avoid the activation of pathways linked to side effects whilst still producing the desired therapeutic effect. In this respect, a deeper understanding of receptor dynamics and implicated allosteric communication networks in signaling bias can accelerate the research on novel biased drug candidates. In this review, we aim to provide an overview of computational methods and techniques for studying allosteric communication and signaling bias in GPCRs. This includes (i) the detection of allosteric communication networks and (ii) the application of network theory for extracting relevant information pipelines and highly communicated sites in GPCRs. We focus on the most recent research and highlight structural insights obtained based on the framework of allosteric communication networks and network theory for GPCR signaling bias.
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8
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Li M, Bao Y, Xu R, La H, Guo J. Critical Extracellular Ca 2+ Dependence of the Binding between PTH1R and a G-Protein Peptide Revealed by MD Simulations. ACS Chem Neurosci 2022; 13:1666-1674. [PMID: 35543321 DOI: 10.1021/acschemneuro.2c00176] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The parathyroid hormone type 1 receptor (PTH1R), a canonical class B GPCR, is regulated by a positive allosteric modulator, extracellular Ca2+. Calcium ions prolong the residence time of PTH on the PTH1R, leading to increased receptor activation and duration of cAMP signaling. But the essential mechanism of the allosteric behavior of PTH1R is not fully understood. Here, extensive molecular dynamics (MD) simulations are performed for the PTH1R-G-protein combinations with and without Ca2+ to describe how calcium ions allosterically engage receptor-G-protein coupling. We find that the binding of Ca2+ stabilizes the conformation of the PTH1R-PTH-spep (the α5 helix of Gs protein) complex, especially the extracellular loop 1 (ECL1). Moreover, the MM-GBSA result indicates that Ca2+ allosterically promotes the interaction between PTH1R and spep, consistent with the observation of steered molecular dynamics (SMD) simulations. We further illuminate the possible allosteric signaling pathway from the stable Ca2+-coupling site to the intracellular G-protein binding site. These results unveil structural determinants for Ca2+ allosterism in the PTH1R-PTH-spep complex and give insights into pluridimensional GPCR signaling regulated by calcium ions.
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Affiliation(s)
- Mengrong Li
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yiqiong Bao
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Ran Xu
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Honggui La
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jingjing Guo
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
- Engineering Research Centre of Applied Technology on Machine Translation and Artificial Intelligence, Faculty of Applied Science, Macao Polytechnic University, Macao 999078, China
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9
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Frimann TM, Ko SK, Harris P, Bukrinski JT, Peters GHJ. In-silico study of the interactions between acylated glucagon like-peptide-1 analogues and the native receptor. J Biomol Struct Dyn 2022:1-15. [PMID: 35612899 DOI: 10.1080/07391102.2022.2078409] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have performed a series of multiple molecular dynamics (MD) simulations of glucagon-like peptide-1 (GLP-1) and acylated GLP-1 analogues in complex with the endogenous receptor (GLP-1R) to obtain a molecular understanding of how fatty acid (FA) chain structure, acylation position on the peptide, and presence of a linker affect the binding. MD simulations were analysed to extract heatmaps of receptor-peptide interaction patterns and to determine the free energy of binding using the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) approach. The extracted free energies from MM-PBSA calculations are in qualitative agreement with experimentally determined potencies. Furthermore, the interaction patterns seen in the receptor-GLP-1 complex simulations resemble previously reported binding interactions validating the simulations. Analysing the receptor-GLP-1 analogue complex simulations, we found that the major differences between the systems stem from FA interactions and positioning of acylation in the peptide. Hydrophobic interactions between the FA chain and a hydrophobic patch on the extracellular domain contribute significantly to the binding affinity. Acylation on Lys26 resulted in noticeably more interactions between the FA chain and the extracellular domain hydrophobic patch than found for acylation on Lys34 and Lys38, respectively. The presence of a charged linker between the peptide and FA chain can potentially stabilise the complex by forming hydrogen bonds to arginine residues in the linker region between the extracellular domain and the transmembrane domain. A molecular understanding of the fatty acid structure and its effect on binding provides important insights into designing acylated agonists for GLP-1R.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Tine Maja Frimann
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Suk Kyu Ko
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Pernille Harris
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark.,Department of Chemistry, H.C. Ørsted Institute, University of Copenhagen, Copenhagen, Denmark
| | | | - Günther H J Peters
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
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10
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Zhang F, Yuan Y, Chen Y, Chen J, Guo Y, Pu X. Molecular insights into the allosteric coupling mechanism between an agonist and two different transducers for μ-opioid receptors. Phys Chem Chem Phys 2022; 24:5282-5293. [PMID: 35170592 DOI: 10.1039/d1cp05736g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
G protein-coupled receptors (GPCRs) as the most important class of pharmacological targets regulate G-protein and β-arrestin-mediated signaling through allosteric interplay, which are responsible for different biochemical and physiological actions like therapeutic efficacy and side effects. However, the allosteric mechanism underlying preferentially recruiting one transducer versus the other has been poorly understood, limiting drug design. Motivated by this issue, we utilize accelerated molecular dynamics simulation coupled with potential of mean force (PMF), molecular mechanics Poisson Boltzmann surface area (MM/PBSA) and protein structure network (PSN) to study two ternary complex systems of a representative class A GPCR (μ-opioid receptor (μOR)) bound by an agonist and one specific transducer (G-protein and β-arrestin). The results show that no significant difference exists in the whole structure of μOR between two transducer couplings, but displays transducer-dependent changes in the intracellular binding region of μOR, where the β-arrestin coupling results in a narrower crevice with TM7 inward movement compared with the G-protein. In addition, both the G-protein and β-arrestin coupling can increase the binding affinity of the agonist to the receptor. However, the interactions between the agonist and μOR also exhibit transducer-specific changes, in particular for the interaction with ECL2 that plays an important role in recruiting β-arrestin. The allosteric network analysis further indicates that Y1483.33, F1523.37, F1563.41, N1914.49, T1603.45, Y1062.42, W2936.48, F2896.44, I2485.54 and Y2525.58 play important roles in equally activating G-protein and β-arrestin. In contrast, M1613.46 and R1653.50 devote important contributions to preferentially recruit G-protein while D1643.49 and R179ICL2 are revealed to be important for selectively activating β-arrestin. The observations provide useful information for understanding the biased activation mechanism.
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Affiliation(s)
- Fuhui Zhang
- Faculty of Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China.
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu, Sichuan 610041, People's Republic of China
| | - Yichi Chen
- Faculty of Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China.
| | - Jianfang Chen
- Faculty of Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China.
| | - Yanzhi Guo
- Faculty of Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China.
| | - Xuemei Pu
- Faculty of Chemistry, Sichuan University, Chengdu, Sichuan 610064, People's Republic of China.
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11
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Madhu MK, Debroy A, Murarka RK. Molecular Insights into Phosphorylation-Induced Allosteric Conformational Changes in a β 2-Adrenergic Receptor. J Phys Chem B 2022; 126:1917-1932. [PMID: 35196859 DOI: 10.1021/acs.jpcb.1c08610] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The large conformational flexibility of G protein-coupled receptors (GPCRs) has been a puzzle in structural and pharmacological studies for the past few decades. Apart from structural rearrangements induced by ligands, enzymatic phosphorylations by GPCR kinases (GRKs) at the carboxy-terminal tail (C-tail) of a GPCR also make conformational alterations to the transmembrane helices and facilitates the binding of one of its transducer proteins named β-arrestin. The phosphorylation-induced conformational transition of the receptor that causes specific binding to β-arrestin but prevents the association of other transducers such as G proteins lacks atomistic understanding and is elusive to experimental studies. Using microseconds of all-atom conventional and Gaussian accelerated molecular dynamics (GaMD) simulations, we investigate the allosteric mechanism of phosphorylation induced-conformational changes in β2-adrenergic receptor, a well-characterized GPCR model system. Free energy profiles reveal that the phosphorylated receptor samples a new conformational state in addition to the canonical active state corroborating with recent nuclear magnetic resonance experimental findings. The new state has a smaller intracellular cavity that is likely to accommodate β-arrestin better than G protein. Using contact map and inter-residue interaction energy calculations, we found the phosphorylated C-tail adheres to the cytosolic surface of the transmembrane domain of the receptor. Transfer entropy calculations show that the C-tail residues drive the correlated motions of TM residues, and the allosteric signal is relayed via several residues at the cytosolic surface. Our results also illustrate how the redistribution of inter-residue nonbonding interaction couples with the allosteric communication from the phosphorylated C-tail to the transmembrane. Atomistic insight into phosphorylation-induced β-arrestin specific conformation is therapeutically important to design drugs with higher efficacy and fewer side effects. Our results, therefore, open novel opportunities to fine-tune β-arrestin bias in GPCR signaling.
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Affiliation(s)
- Midhun K Madhu
- Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal 462066, MP, India
| | - Annesha Debroy
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal 462066, MP, India
| | - Rajesh K Murarka
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhopal 462066, MP, India
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12
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Salas-Estrada L, Fiorillo B, Filizola M. Metadynamics simulations leveraged by statistical analyses and artificial intelligence-based tools to inform the discovery of G protein-coupled receptor ligands. Front Endocrinol (Lausanne) 2022; 13:1099715. [PMID: 36619585 PMCID: PMC9816996 DOI: 10.3389/fendo.2022.1099715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 12/12/2022] [Indexed: 12/25/2022] Open
Abstract
G Protein-Coupled Receptors (GPCRs) are a large family of membrane proteins with pluridimensional signaling profiles. They undergo ligand-specific conformational changes, which in turn lead to the differential activation of intracellular signaling proteins and the consequent triggering of a variety of biological responses. This conformational plasticity directly impacts our understanding of GPCR signaling and therapeutic implications, as do ligand-specific kinetic differences in GPCR-induced transducer activation/coupling or GPCR-transducer complex stability. High-resolution experimental structures of ligand-bound GPCRs in the presence or absence of interacting transducers provide important, yet limited, insights into the highly dynamic process of ligand-induced activation or inhibition of these receptors. We and others have complemented these studies with computational strategies aimed at characterizing increasingly accurate metastable conformations of GPCRs using a combination of metadynamics simulations, state-of-the-art algorithms for statistical analyses of simulation data, and artificial intelligence-based tools. This minireview provides an overview of these approaches as well as lessons learned from them towards the identification of conformational states that may be difficult or even impossible to characterize experimentally and yet important to discover new GPCR ligands.
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13
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Chen J, Liu J, Yuan Y, Chen X, Zhang F, Pu X. Molecular Mechanisms of Diverse Activation Stimulated by Different Biased Agonists for the β2-Adrenergic Receptor. J Chem Inf Model 2021; 62:5175-5192. [PMID: 34802238 DOI: 10.1021/acs.jcim.1c01016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
β2AR is an important drug target protein involving many diseases. Biased drugs induce specific signaling and provide additional clinical utility to optimize β2AR-based therapies. However, the biased signaling mechanism has not been elucidated. Motivated by the issue, we chose four agonists with divergent bias (balanced agonist, G-protein-biased agonist, and β-arrestin-biased agonists) and utilized Gaussian accelerated molecular dynamics simulation coupled with a dynamic network to probe the molecular mechanisms of distinct biased activation induced by the structural differences between the four agonists. Our simulations reveal that the G-protein-biased agonist induces an open conformation with the outward shifts of TM6 and TM7 for the intracellular domain, which will be beneficial to couple G protein. In contrast, the β-arrestin-biased agonists regulate an occluded conformation with a slightly outward movement of TM6 and an inward shift of TM7, which should favor β-arrestin signaling. The balanced agonist does not induce an observable outward shift for TM6 but, along with a slight tilt for TM7, leads to an inactive-like conformation. In addition, our results reveal the first time that ICL3 presents specific conformations with different agonists. The G-protein-biased agonist drives ICL3 to open so that the G protein-binding pocket can be available, while the β-arrestin-biased agonists induce ICL3 to form a closed conformation with a stable local α-helix. MM/PBSA analysis further reveals that the hydroxyl groups in the resorcinol of the G-protein-biased agonist form strong interactions with Y5.38 and S5.42, thus preventing tilting of the TM5 extracellular end. The catechol of the balanced agonist and the β-arrestin-biased ones induces the rearrangement of two hydrophobic residues F6.52 and W6.48. However, different from the balanced agonist, the ethyl substituent of β-arrestin-biased agonists forms additional hydrophobic interactions with W6.48 and F6.51 after the rearrangement, which should contribute to the β-arrestin bias. The shortest pathway analysis further reveals that the three residues Y7.43, N7.45, and N7.49 are crucial for allosterically regulating G-protein-biased signaling, while the two residues W6.48 and F6.44 make an important contribution to regulate β-arrestin-biased signaling. For the balanced agonist NE, the allosteric regulation pathway simultaneously involves the residue associated with G-protein-biased signaling like S5.46 and the residues related to β-arrestin-biased signaling like W6.48 and F6.44, thus producing unbiased signaling. The observations could advance our understanding of the biased activation mechanism on class A GPCRs and provide a useful guideline for the design of biased drugs.
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Affiliation(s)
- Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Jiangting Liu
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu 610041, China
| | - Xin Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Fuhui Zhang
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, China
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14
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Poudel H, Leitner DM. Activation-Induced Reorganization of Energy Transport Networks in the β 2 Adrenergic Receptor. J Phys Chem B 2021; 125:6522-6531. [PMID: 34106712 DOI: 10.1021/acs.jpcb.1c03412] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We compute energy exchange networks (EENs) through the β2 adrenergic receptor (β2AR), a G-protein coupled receptor (GPCR), in inactive and active states, based on the results of molecular dynamics simulations of this membrane bound protein. We introduce a new definition for the reorganization of EENs upon activation that depends on the relative change in rates of energy transfer across noncovalent contacts throughout the protein. On the basis of the reorganized network that we obtain for β2AR upon activation, we identify a branched pathway between the agonist binding site and the cytoplasmic region, where a G-protein binds to the receptor when activated. The pathway includes all of the motifs containing molecular switches previously identified as contributing to the allosteric transition of β2AR upon agonist binding. EENs and their reorganization upon activation are compared with structure-based contact networks computed for the inactive and active states of β2AR.
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Affiliation(s)
- Humanath Poudel
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
| | - David M Leitner
- Department of Chemistry, University of Nevada, Reno, Nevada 89557, United States
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15
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Mondal D, Kolev V, Warshel A. Exploring the activation pathway and G i-coupling specificity of the μ-opioid receptor. Proc Natl Acad Sci U S A 2020; 117:26218-26225. [PMID: 33020275 PMCID: PMC7585030 DOI: 10.1073/pnas.2013364117] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Understanding the activation mechanism of the μ-opioid receptor (μ-OR) and its selective coupling to the inhibitory G protein (Gi) is vital for pharmaceutical research aimed at finding treatments for the opioid overdose crisis. Many attempts have been made to understand the mechanism of the μ-OR activation, following the elucidation of new crystal structures such as the antagonist- and agonist-bound μ-OR. However, the focus has not been placed on the underlying energetics and specificity of the activation process. An energy-based picture would not only help to explain this coupling but also help to explore why other possible options are not common. For example, one would like to understand why μ-OR is more selective to Gi than a stimulatory G protein (Gs). Our study used homology modeling and a coarse-grained model to generate all of the possible "end states" of the thermodynamic cycle of the activation of μ-OR. The end points were further used to generate reasonable intermediate structures of the receptor and the Gi to calculate two-dimensional free energy landscapes. The results of the landscape calculations helped to propose a plausible sequence of conformational changes in the μ-OR and Gi system and for exploring the path that leads to its activation. Furthermore, in silico alanine scanning calculations of the last 21 residues of the C terminals of Gi and Gs were performed to shed light on the selective binding of Gi to μ-OR. Overall, the present work appears to demonstrate the potential of multiscale modeling in exploring the action of G protein-coupled receptors.
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Affiliation(s)
- Dibyendu Mondal
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089
| | - Vesselin Kolev
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089
| | - Arieh Warshel
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089
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16
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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.
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17
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Mattedi G, Acosta-Gutiérrez S, Clark T, Gervasio FL. A combined activation mechanism for the glucagon receptor. Proc Natl Acad Sci U S A 2020; 117:15414-15422. [PMID: 32571939 PMCID: PMC7355025 DOI: 10.1073/pnas.1921851117] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We report on a combined activation mechanism for a class B G-protein-coupled receptor (GPCR), the glucagon receptor. By computing the conformational free-energy landscape associated with the activation of the receptor-agonist complex and comparing it with that obtained with the ternary complex (receptor-agonist-G protein) we show that the agonist stabilizes the receptor in a preactivated complex, which is then fully activated upon binding of the G protein. The proposed mechanism contrasts with the generally assumed GPCR activation mechanism, which proceeds through an opening of the intracellular region allosterically elicited by the binding of the agonist. The mechanism found here is consistent with electron cryo-microscopy structural data and might be general for class B GPCRs. It also helps us to understand the mode of action of the numerous allosteric antagonists of this important drug target.
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Affiliation(s)
- Giulio Mattedi
- Department of Chemistry, University College London, London WC1E 6BT, United Kingdom
| | | | - Timothy Clark
- Computer-Chemistry Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen 91052, Germany
| | - Francesco Luigi Gervasio
- Department of Chemistry, University College London, London WC1E 6BT, United Kingdom;
- Institute of Structural and Molecular Biology, University College London, London WC1E 6BT, United Kingdom
- Pharmaceutical Sciences, University of Geneva, Geneva CH-1211, Switzerland
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18
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Suomivuori CM, Latorraca NR, Wingler LM, Eismann S, King MC, Kleinhenz ALW, Skiba MA, Staus DP, Kruse AC, Lefkowitz RJ, Dror RO. Molecular mechanism of biased signaling in a prototypical G protein-coupled receptor. Science 2020; 367:881-887. [PMID: 32079767 DOI: 10.1126/science.aaz0326] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 01/23/2020] [Indexed: 12/19/2022]
Abstract
Biased signaling, in which different ligands that bind to the same G protein-coupled receptor preferentially trigger distinct signaling pathways, holds great promise for the design of safer and more effective drugs. Its structural mechanism remains unclear, however, hampering efforts to design drugs with desired signaling profiles. Here, we use extensive atomic-level molecular dynamics simulations to determine how arrestin bias and G protein bias arise at the angiotensin II type 1 receptor. The receptor adopts two major signaling conformations, one of which couples almost exclusively to arrestin, whereas the other also couples effectively to a G protein. A long-range allosteric network allows ligands in the extracellular binding pocket to favor either of the two intracellular conformations. Guided by this computationally determined mechanism, we designed ligands with desired signaling profiles.
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Affiliation(s)
- Carl-Mikael Suomivuori
- Department of Computer Science, Stanford University, Stanford, CA 94305, USA.,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Naomi R Latorraca
- Department of Computer Science, Stanford University, Stanford, CA 94305, USA.,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA.,Biophysics Program, Stanford University, Stanford, CA 94305, USA
| | - Laura M Wingler
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.,Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Stephan Eismann
- Department of Computer Science, Stanford University, Stanford, CA 94305, USA.,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA.,Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
| | - Matthew C King
- Department of Computer Science, Stanford University, Stanford, CA 94305, USA.,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Alissa L W Kleinhenz
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.,Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,School of Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Meredith A Skiba
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Dean P Staus
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.,Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Andrew C Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Robert J Lefkowitz
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.,Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Ron O Dror
- Department of Computer Science, Stanford University, Stanford, CA 94305, USA. .,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.,Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA.,Biophysics Program, Stanford University, Stanford, CA 94305, USA
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19
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Saleh N, Wang Y, Nissen P, Lindorff-Larsen K. Allosteric modulation of the sarcoplasmic reticulum Ca 2+ ATPase by thapsigargin via decoupling of functional motions. Phys Chem Chem Phys 2019; 21:21991-21995. [PMID: 31552962 DOI: 10.1039/c9cp04736k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The sarcoplasmic reticulum Ca2+-ATPase (SERCA) is a widely studied member of the large family of phosphorylation(P)-type ATPase membrane transporters. Ligands and nucleotide binding naturally modulate the conformational space of P-type ATPases through allosteric inter-domain communications. Whereas many inhibitory ATPase ligands act by directly blocking substrate uptake or release, SERCA is a target for thapsigargin (TG), a plant-derived natural product that allosterically inhibits the transport cycle. While thapsigargin's inhibitory effects on SERCA have been widely studied experimentally, the molecular mechanisms underlying these remain incompletely understood. Here, we apply modelling and molecular simulations to probe the effects of TG binding to the major functional states along SERCA's reaction cycle. Our results provide insight into the atomic-level details of the conformational changes induced by TG binding to SERCA, and suggest mechanisms for its effect. Since other P-type ATPases share closely related reaction cycles, our data suggests that similar modulators might exist for these.
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Affiliation(s)
- Noureldin Saleh
- Linderstrøm-Lang Centre for Protein Science, Dept. of Biology, University of Copenhagen, Copenhagen, Denmark.
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20
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Nussinov R, Tsai CJ, Jang H. Does Ras Activate Raf and PI3K Allosterically? Front Oncol 2019; 9:1231. [PMID: 31799192 PMCID: PMC6874141 DOI: 10.3389/fonc.2019.01231] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/28/2019] [Indexed: 12/11/2022] Open
Abstract
The mechanism through which oncogenic Ras activates its effectors is vastly important to resolve. If allostery is at play, then targeting allosteric pathways could help in quelling activation of MAPK (Raf/MEK/ERK) and PI3K (PI3K/Akt/mTOR) cell proliferation pathways. On the face of it, allosteric activation is reasonable: Ras binding perturbs the conformational ensembles of its effectors. Here, however, we suggest that at least for Raf, PI3K, and NORE1A (RASSF5), that is unlikely. Raf's long disordered linker dampens effective allosteric activation. Instead, we suggest that the high-affinity Ras–Raf binding relieves Raf's autoinhibition, shifting Raf's ensemble from the inactive to the nanocluster-mediated dimerized active state, as Ras also does for NORE1A. PI3K is recruited and allosterically activated by RTK (e.g., EGFR) at the membrane. Ras restrains PI3K's distribution and active site orientation. It stabilizes and facilitates PIP2 binding at the active site and increases the PI3K residence time at the membrane. Thus, RTKs allosterically activate PI3Kα; however, merging their action with Ras accomplishes full activation. Here we review their activation mechanisms in this light and draw attention to implications for their pharmacology.
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Affiliation(s)
- Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, United States.,Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Chung-Jung Tsai
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, United States
| | - Hyunbum Jang
- Cancer and Inflammation Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, United States
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21
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Wang J, Alekseenko A, Kozakov D, Miao Y. Improved Modeling of Peptide-Protein Binding Through Global Docking and Accelerated Molecular Dynamics Simulations. Front Mol Biosci 2019; 6:112. [PMID: 31737642 PMCID: PMC6835073 DOI: 10.3389/fmolb.2019.00112] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/09/2019] [Indexed: 01/31/2023] Open
Abstract
Peptides mediate up to 40% of known protein-protein interactions in higher eukaryotes and play a key role in cellular signaling, protein trafficking, immunology, and oncology. However, it is challenging to predict peptide-protein binding with conventional computational modeling approaches, due to slow dynamics and high peptide flexibility. Here, we present a prototype of the approach which combines global peptide docking using ClusPro PeptiDock and all-atom enhanced simulations using Gaussian accelerated molecular dynamics (GaMD). For three distinct model peptides, the lowest backbone root-mean-square deviations (RMSDs) of their bound conformations relative to X-ray structures obtained from PeptiDock were 3.3–4.8 Å, being medium quality predictions according to the Critical Assessment of PRediction of Interactions (CAPRI) criteria. GaMD simulations refined the peptide-protein complex structures with significantly reduced peptide backbone RMSDs of 0.6–2.7 Å, yielding two high quality (sub-angstrom) and one medium quality models. Furthermore, the GaMD simulations identified important low-energy conformational states and revealed the mechanism of peptide binding to the target proteins. Therefore, PeptiDock+GaMD is a promising approach for exploring peptide-protein interactions.
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Affiliation(s)
- Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, United States
| | - Andrey Alekseenko
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, United States.,Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, United States
| | - Dima Kozakov
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, United States.,Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, United States
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, United States
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22
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Ibrahim P, Wifling D, Clark T. Universal Activation Index for Class A GPCRs. J Chem Inf Model 2019; 59:3938-3945. [DOI: 10.1021/acs.jcim.9b00604] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Passainte Ibrahim
- Computer-Chemie-Centrum, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Nägelsbachstrasse 25, 91052 Erlangen, Germany
| | - David Wifling
- Pharmaceutical/Medicinal Chemistry II, Institute of Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93040 Regensburg, Germany
| | - Timothy Clark
- Computer-Chemie-Centrum, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Nägelsbachstrasse 25, 91052 Erlangen, Germany
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23
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Wang J, Miao Y. Mechanistic Insights into Specific G Protein Interactions with Adenosine Receptors. J Phys Chem B 2019; 123:6462-6473. [PMID: 31283874 DOI: 10.1021/acs.jpcb.9b04867] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Coupling between G-protein-coupled receptors (GPCRs) and the G proteins is a key step in cellular signaling. Despite extensive experimental and computational studies, the mechanism of specific GPCR-G protein coupling remains poorly understood. This has greatly hindered effective drug design of GPCRs that are primary targets of ∼1/3 of currently marketed drugs. Here, we have employed all-atom simulations using a robust Gaussian accelerated molecular dynamics (GaMD) method to decipher the mechanism of the GPCR-G protein interactions. Adenosine receptors (ARs) were used as model systems based on very recently determined cryo-EM structures of the A1AR and A2AAR coupled with the Gi and Gs proteins, respectively. Changing the Gi protein to the Gs led to increased fluctuations in the A1AR and agonist adenosine (ADO), while agonist 5'-N-ethylcarboxamidoadenosine (NECA) binding in the A2AAR could be still stabilized upon changing the Gs protein to the Gi. Free energy calculations identified one stable low-energy conformation for each of the A1AR-Gi and A2AAR-Gs complexes as in the cryo-EM structures, similarly for the A2AAR-Gi complex. In contrast, the ADO agonist and Gs protein sampled multiple conformations in the A1AR-Gs system. GaMD simulations thus indicated that the A1AR preferred to couple with the Gi protein to the Gs, while the A2AAR could couple with both the Gs and Gi proteins, being highly consistent with experimental findings of the ARs. More importantly, detailed analysis of the atomic simulations showed that the specific AR-G protein coupling resulted from remarkably complementary residue interactions at the protein interface, involving mainly the receptor transmembrane 6 helix and the Gα α5 helix and α4-β6 loop. In summary, the GaMD simulations have provided unprecedented insights into the dynamic mechanism of specific GPCR-G protein interactions at an atomistic level.
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Affiliation(s)
- Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences , University of Kansas , Lawrence , Kansas 66047 , United States
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences , University of Kansas , Lawrence , Kansas 66047 , United States
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24
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Ibrahim P, Clark T. Metadynamics simulations of ligand binding to GPCRs. Curr Opin Struct Biol 2019; 55:129-137. [PMID: 31100549 DOI: 10.1016/j.sbi.2019.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/28/2019] [Accepted: 04/05/2019] [Indexed: 11/17/2022]
Abstract
Recent developments in metadynamics simulation techniques for ligand binding to Class A GPCRs are described and the results obtained elucidated. The computational protocol makes good use of modern massively parallel hardware, making simulations of the binding/unbinding process routine. The simulations reveal unprecedented details of the ligand-binding pathways, including multiple binding sites in many cases. Free energies of binding are reproduced very well and the simulations allow prediction of the efficacy (agonist, antagonist etc.) of ligands.
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Affiliation(s)
- Passainte Ibrahim
- Computer-Chemistry Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg, Nägelsbachstr. 25, 91052 Erlangen, Germany
| | - Timothy Clark
- Computer-Chemistry Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg, Nägelsbachstr. 25, 91052 Erlangen, Germany.
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25
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Renault P, Louet M, Marie J, Labesse G, Floquet N. Molecular Dynamics Simulations of the Allosteric Modulation of the Adenosine A2A Receptor by a Mini-G Protein. Sci Rep 2019; 9:5495. [PMID: 30940903 PMCID: PMC6445292 DOI: 10.1038/s41598-019-41980-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 03/19/2019] [Indexed: 01/14/2023] Open
Abstract
Through their coupling to G proteins, G Protein-Coupled Receptors (GPCRs) trigger cellular responses to various signals. Some recent experiments have interestingly demonstrated that the G protein can also act on the receptor by favoring a closed conformation of its orthosteric site, even in the absence of a bound agonist. In this work, we explored such an allosteric modulation by performing extensive molecular dynamics simulations on the adenosine A2 receptor (A2aR) coupled to the Mini-Gs protein. In the presence of the Mini-Gs, we confirmed a restriction of the receptor’s agonist binding site that can be explained by a modulation of the intrinsic network of contacts of the receptor. Of interest, we observed similar effects with the C-terminal helix of the Mini-Gs, showing that the observed effect on the binding pocket results from direct local contacts with the bound protein partner that cause a rewiring of the whole receptor’s interaction network.
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Affiliation(s)
- Pedro Renault
- Institut des Biomolécules Max Mousseron (IBMM), CNRS UMR5247, Université de Montpellier, ENSCM, 34090, Montpellier, France.,Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090, Montpellier, France
| | - Maxime Louet
- Institut des Biomolécules Max Mousseron (IBMM), CNRS UMR5247, Université de Montpellier, ENSCM, 34090, Montpellier, France
| | - Jacky Marie
- Institut des Biomolécules Max Mousseron (IBMM), CNRS UMR5247, Université de Montpellier, ENSCM, 34090, Montpellier, France
| | - Gilles Labesse
- Centre de Biochimie Structurale, Université de Montpellier, CNRS, INSERM, 34090, Montpellier, France
| | - Nicolas Floquet
- Institut des Biomolécules Max Mousseron (IBMM), CNRS UMR5247, Université de Montpellier, ENSCM, 34090, Montpellier, France.
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26
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Current status of multiscale simulations on GPCRs. Curr Opin Struct Biol 2019; 55:93-103. [DOI: 10.1016/j.sbi.2019.02.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 02/19/2019] [Accepted: 02/27/2019] [Indexed: 01/14/2023]
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27
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Wang J, Miao Y. Recent advances in computational studies of GPCR-G protein interactions. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 116:397-419. [PMID: 31036298 PMCID: PMC6986689 DOI: 10.1016/bs.apcsb.2018.11.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Protein-protein interactions are key in cellular signaling. G protein-coupled receptors (GPCRs), the largest superfamily of human membrane proteins, are able to transduce extracellular signals (e.g., hormones and neurotransmitters) to intracellular proteins, in particular the G proteins. Since GPCRs serve as primary targets of ~1/3 of currently marketed drugs, it is important to understand mechanisms of GPCR signaling in order to design selective and potent drug molecules. This chapter focuses on recent advances in computational studies of the GPCR-G protein interactions using bioinformatics, protein-protein docking and molecular dynamics simulation approaches.
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Affiliation(s)
- Jinan Wang
- 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.
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28
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Saleh N, Kleinau G, Heyder N, Clark T, Hildebrand PW, Scheerer P. Binding, Thermodynamics, and Selectivity of a Non-peptide Antagonist to the Melanocortin-4 Receptor. Front Pharmacol 2018; 9:560. [PMID: 29910730 PMCID: PMC5992272 DOI: 10.3389/fphar.2018.00560] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 05/10/2018] [Indexed: 11/22/2022] Open
Abstract
The melanocortin-4 receptor (MC4R) is a potential drug target for treatment of obesity, anxiety, depression, and sexual dysfunction. Crystal structures for MC4R are not yet available, which has hindered successful structure-based drug design. Using microsecond-scale molecular-dynamics simulations, we have investigated selective binding of the non-peptide antagonist MCL0129 to a homology model of human MC4R (hMC4R). This approach revealed that, at the end of a multi-step binding process, MCL0129 spontaneously adopts a binding mode in which it blocks the agonistic-binding site. This binding mode was confirmed in subsequent metadynamics simulations, which gave an affinity for human hMC4R that matches the experimentally determined value. Extending our simulations of MCL0129 binding to hMC1R and hMC3R, we find that receptor subtype selectivity for hMC4R depends on few amino acids located in various structural elements of the receptor. These insights may support rational drug design targeting the melanocortin systems.
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Affiliation(s)
- Noureldin Saleh
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Computational Modelling and Dynamics of Molecular Complexes, Berlin, Germany
| | - Gunnar Kleinau
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
| | - Nicolas Heyder
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
| | - Timothy Clark
- Computer-Chemie-Centrum, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Peter W Hildebrand
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Computational Modelling and Dynamics of Molecular Complexes, Berlin, Germany.,Institute of Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
| | - Patrick Scheerer
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
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29
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Saleh N, Hucke O, Kramer G, Schmidt E, Montel F, Lipinski R, Ferger B, Clark T, Hildebrand PW, Tautermann CS. Multiple Binding Sites Contribute to the Mechanism of Mixed Agonistic and Positive Allosteric Modulators of the Cannabinoid CB1 Receptor. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201708764] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Noureldin Saleh
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health; Institute of Medical Physics and Biophysics; Charitéplatz 1 10117 Berlin Germany
| | - Oliver Hucke
- Department for Medicinal Chemistry; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Gert Kramer
- Department for CNS research; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Esther Schmidt
- Department for Drug Discovery Sciences; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Florian Montel
- Department for Medicinal Chemistry; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Radoslaw Lipinski
- Department for Medicinal Chemistry; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Boris Ferger
- Department for CNS research; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
| | - Timothy Clark
- Computer-Chemie-Centrum; Friedrich-Alexander-Universität Erlangen-Nürnberg; Nägelsbachstraße 25 91052 Erlangen Germany
| | - Peter W. Hildebrand
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health; Institute of Medical Physics and Biophysics; Charitéplatz 1 10117 Berlin Germany
- Universität Leipzig; Institute of Medical Physics and Biophysics; Härtelstraße 16-18 04107 Leipzig Germany
| | - Christofer S. Tautermann
- Department for Medicinal Chemistry; Boehringer Ingelheim Pharma GmbH & Co KG; Birkendorfer Straße 65 88397 Biberach an der Riss Germany
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Saleh N, Hucke O, Kramer G, Schmidt E, Montel F, Lipinski R, Ferger B, Clark T, Hildebrand PW, Tautermann CS. Multiple Binding Sites Contribute to the Mechanism of Mixed Agonistic and Positive Allosteric Modulators of the Cannabinoid CB1 Receptor. Angew Chem Int Ed Engl 2018; 57:2580-2585. [PMID: 29314474 DOI: 10.1002/anie.201708764] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 12/23/2017] [Indexed: 12/27/2022]
Abstract
The cannabinoid CB1 receptor (CB1R) is an abundant metabotropic G-protein-coupled receptor that has been difficult to address therapeutically because of CNS side effects exerted by orthosteric drug candidates. Recent efforts have focused on developing allosteric modulators that target CB1R. Compounds from the recently discovered class of mixed agonistic and positive allosteric modulators (Ago-PAMs) based on 2-phenylindoles have shown promising functional and binding properties as CB1R ligands. Here, we identify binding modes of both the CP 55,940 agonist and GAT228, a 2-phenylindole allosteric modulator, by using our metadynamics simulation protocol, and quantify their affinity and cooperativity by atomistic simulations. We demonstrate the involvement of multiple adjunct binding sites in the Ago-PAM characteristics of the 2-phenylindole modulators and explain their ability to compete with orthosteric agonists at higher concentrations. We validate these results experimentally by showing the contribution of multiple sites on the allosteric binding of ZCZ011, another homologous member of the class, together with the orthosteric agonist.
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Affiliation(s)
- Noureldin Saleh
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Charitéplatz 1, 10117, Berlin, Germany
| | - Oliver Hucke
- Department for Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Gert Kramer
- Department for CNS research, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Esther Schmidt
- Department for Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Florian Montel
- Department for Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Radoslaw Lipinski
- Department for Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Boris Ferger
- Department for CNS research, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
| | - Timothy Clark
- Computer-Chemie-Centrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Peter W Hildebrand
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Charitéplatz 1, 10117, Berlin, Germany.,Universität Leipzig, Institute of Medical Physics and Biophysics, Härtelstraße 16-18, 04107, Leipzig, Germany
| | - Christofer S Tautermann
- Department for Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co KG, Birkendorfer Straße 65, 88397, Biberach an der Riss, Germany
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Clark T. G-Protein coupled receptors: answers from simulations. Beilstein J Org Chem 2017; 13:1071-1078. [PMID: 28684986 PMCID: PMC5480328 DOI: 10.3762/bjoc.13.106] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/16/2017] [Indexed: 12/31/2022] Open
Abstract
Molecular-dynamics (MD) simulations are playing an increasingly important role in research into the modes of action of G-protein coupled receptors (GPCRs). In this field, MD simulations are unusually important as, because of the difficult experimental situation, they often offer the only opportunity to determine structural and mechanistic features in atomistic detail. Modern combinations of soft- and hardware have made MD simulations a powerful tool in GPCR research. This is important because GPCRs are targeted by approximately half of the drugs on the market, so that computer-aided drug design plays a major role in GPCR research.
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Affiliation(s)
- Timothy Clark
- Computer-Chemie-Centrum, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstr. 25, 91052 Erlangen, Germany
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