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Lešnik S, Bren U, Domratcheva T, Bondar AN. Fentanyl and the Fluorinated Fentanyl Derivative NFEPP Elicit Distinct Hydrogen-Bond Dynamics of the Opioid Receptor. J Chem Inf Model 2023; 63:4732-4748. [PMID: 37498626 DOI: 10.1021/acs.jcim.3c00197] [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: 07/28/2023]
Abstract
The development of safe therapeutics to manage pain is of central interest for biomedical applications. The fluorinated fentanyl derivative N-(3-fluoro-1-phenethylpiperidin-4-yl)-N-phenylpropionamide (NFEPP) is potentially a safer alternative to fentanyl because unlike fentanyl─which binds to the μ-opioid receptor (MOR) at both physiological and acidic pH─NFEPP might bind to the MOR only at acidic pH typical of inflamed tissue. Knowledge of the protonation-coupled dynamics of the receptor-drug interactions is thus required to understand the molecular mechanism by which receptor activation initiates cell signaling to silence pain. To this end, here we have carried out extensive atomistic simulations of the MOR in different protonation states, in the absence of opioid drugs, and in the presence of fentanyl vs NFEPP. We used graph-based analyses to characterize internal hydrogen-bond networks that could contribute to the activation of the MOR. We find that fentanyl and NFEPP prefer distinct binding poses and that, in their binding poses, fentanyl and NFEPP partake in distinct internal hydrogen-bond networks, leading to the cytoplasmic G-protein-binding region. Moreover, the protonation state of functionally important aspartic and histidine side chains impacts hydrogen-bond networks that extend throughout the receptor, such that the ligand-bound MOR presents at its cytoplasmic G-protein-binding side, a hydrogen-bonding environment where dynamics depend on whether fentanyl or NFEPP is bound, and on the protonation state of specific MOR groups. The exquisite sensitivity of the internal protein-water hydrogen-bond network to the protonation state and to details of the drug binding could enable the MOR to elicit distinct pH- and opioid-dependent responses at its cytoplasmic G-protein-binding site.
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Affiliation(s)
- Samo Lešnik
- Faculty of Chemistry and Chemical Engineering, Laboratory of Physical Chemistry and Chemical Thermodynamics, University of Maribor, Smetanova ulica 17, SI-2000 Maribor, Slovenia
- Institute for Environmental Protection and Sensors, Beloruska ulica 7, 2000 Maribor, Slovenia
| | - Urban Bren
- Faculty of Chemistry and Chemical Engineering, Laboratory of Physical Chemistry and Chemical Thermodynamics, University of Maribor, Smetanova ulica 17, SI-2000 Maribor, Slovenia
- Institute for Environmental Protection and Sensors, Beloruska ulica 7, 2000 Maribor, Slovenia
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, SI-6000 Koper, Slovenia
| | - Tatiana Domratcheva
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
- Department of Biomolecular Mechanisms, Max-Plank-Institute fur Medizinische Forschung, D-69120 Heidelberg, Germany
| | - Ana-Nicoleta Bondar
- Faculty of Physics, University of Bucharest, Atomiştilor 405, 077125 Măgurele, Romania
- Institute of Computational Biomedicine, IAS-5/INM-9, Forschungszentrum Jülich, Wilhelm-Johnen Straße, 5428 Jülich, Germany
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2
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Zhang D, Liu Y, Zaidi SA, Xu L, Zhan Y, Chen A, Guo J, Huang X, Roth BL, Katritch V, Cherezov V, Zhang H. Structural insights into angiotensin receptor signaling modulation by balanced and biased agonists. EMBO J 2023; 42:e112940. [PMID: 37038975 PMCID: PMC10233375 DOI: 10.15252/embj.2022112940] [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: 10/27/2022] [Revised: 02/22/2023] [Accepted: 03/21/2023] [Indexed: 04/12/2023] Open
Abstract
The peptide hormone angiotensin II regulates blood pressure mainly through the type 1 angiotensin II receptor AT1 R and its downstream signaling proteins Gq and β-arrestin. AT1 R blockers, clinically used as antihypertensive drugs, inhibit both signaling pathways, whereas AT1 R β-arrestin-biased agonists have shown great potential for the treatment of acute heart failure. Here, we present a cryo-electron microscopy (cryo-EM) structure of the human AT1 R in complex with a balanced agonist, Sar1 -AngII, and Gq protein at 2.9 Å resolution. This structure, together with extensive functional assays and computational modeling, reveals the molecular mechanisms for AT1 R signaling modulation and suggests that a major hydrogen bond network (MHN) inside the receptor serves as a key regulator of AT1 R signal transduction from the ligand-binding pocket to both Gq and β-arrestin pathways. Specifically, we found that the MHN mutations N1113.35 A and N2947.45 A induce biased signaling to Gq and β-arrestin, respectively. These insights should facilitate AT1 R structure-based drug discovery for the treatment of cardiovascular diseases.
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Affiliation(s)
- Dongqi Zhang
- Hangzhou Institute of Innovative Medicine, Institute of Pharmacology and Toxicology, Zhejiang Province Key Laboratory of Anti‐Cancer Drug Research, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Yongfeng Liu
- Department of PharmacologyUniversity of North Carolina School of MedicineChapel HillNCUSA
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP)University of North Carolina School of MedicineChapel HillNCUSA
| | - Saheem A Zaidi
- Department of Quantitative and Computational BiologyUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Lingyi Xu
- Department of BiophysicsZhejiang University School of MedicineHangzhouChina
- Department of Neurology of the Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouChina
| | - Yuting Zhan
- Hangzhou Institute of Innovative Medicine, Institute of Pharmacology and Toxicology, Zhejiang Province Key Laboratory of Anti‐Cancer Drug Research, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Anqi Chen
- Hangzhou Institute of Innovative Medicine, Institute of Pharmacology and Toxicology, Zhejiang Province Key Laboratory of Anti‐Cancer Drug Research, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
| | - Jiangtao Guo
- Department of BiophysicsZhejiang University School of MedicineHangzhouChina
- Department of Neurology of the Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouChina
| | - Xi‐Ping Huang
- Department of PharmacologyUniversity of North Carolina School of MedicineChapel HillNCUSA
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP)University of North Carolina School of MedicineChapel HillNCUSA
| | - Bryan L Roth
- Department of PharmacologyUniversity of North Carolina School of MedicineChapel HillNCUSA
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP)University of North Carolina School of MedicineChapel HillNCUSA
- Division of Chemical Biology and Medicinal ChemistryUniversity of North Carolina School of MedicineChapel HillNCUSA
| | - Vsevolod Katritch
- Department of Quantitative and Computational BiologyUniversity of Southern CaliforniaLos AngelesCAUSA
- Department of Chemistry, Bridge InstituteUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Vadim Cherezov
- Department of Chemistry, Bridge InstituteUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Haitao Zhang
- Hangzhou Institute of Innovative Medicine, Institute of Pharmacology and Toxicology, Zhejiang Province Key Laboratory of Anti‐Cancer Drug Research, College of Pharmaceutical SciencesZhejiang UniversityHangzhouChina
- The Second Affiliated HospitalZhejiang University School of MedicineHangzhouChina
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3
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Patidar I, Palaka BK, Katike U, Velmurugan Ilavarasi A, Tulsi, Mohanty SS, Ampasala DR. Structural elucidation of ETHR-A and ETHR-B from Plutella xylostella and insight into non-conservative mutations in transmembrane helix-6. J Biomol Struct Dyn 2023; 41:12572-12585. [PMID: 36683288 DOI: 10.1080/07391102.2023.2167112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 01/05/2023] [Indexed: 01/24/2023]
Abstract
The development of Diamondback moth (DBM) depends on the ecdysis triggering hormone receptor (ETHR); a neuronal membrane G-protein coupled receptor (GPCR) connected to the metamorphosis cascade. Lepidopteran insect DBM is an infamous pest of cruciferous plants. This study examined the full-length coding sequences (CDS) of PxETHR-A and PxETHR-B from the DBM genome. The three-dimensional (3 D) models of both receptors were generated in an inactive state. The behaviour and stability of receptors were examined using molecular dynamics simulations in a lipid membrane system for 300 ns and established a GPCR family-based view. Secondary interactions within receptors were studied to know more about factors contributing to their stability. Multiple sequence alignment revealed conserved features of insect ETHRs those compared to the GPCR family proteins. These features were helpful during the evaluation of the molecular models of both receptors. Side-chain orientation of conserved residues, non-conserved and conserved hydrogen-bond networks (HBN) and hydrophobic clusters were examined in the structures of both receptors. The non-conserved residues L6.35, T6.39, C/S6.43, and L6.48, are present in a conserved position on the transmembrane helix-6 (TM6) of ETHRs. In TM6, PxETHR-A and PxETHR-B differ at positions C/S6.43 and Y/F6.51, both being part of the HBN.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ishwar Patidar
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Bhagath Kumar Palaka
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Umamahesh Katike
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | | | - Tulsi
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Saswati Sarita Mohanty
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Dinakara Rao Ampasala
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
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4
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Amado P, Zegers J, Yarur HE, Gysling K. Transcriptional Regulation, Signaling Pathways, and Subcellular Localization of Corticotropin-Releasing Factor Receptors in the Central Nervous System. Mol Pharmacol 2022; 102:280-287. [PMID: 36167424 DOI: 10.1124/molpharm.121.000476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 09/12/2022] [Indexed: 12/24/2022] Open
Abstract
Corticotropin-releasing factor (CRF) receptors CRF-R1 and CRF-R2 are differentially distributed in body tissues, and although they respond differentially to stimuli due to their association with different signaling pathways, both receptors have a fundamental role in the response and adaptation to stressful stimuli. Here, we summarize the reported data on different forms of CRF-R1 and CRF-R2 regulation as well as on their subcellular localization. Although the presence of R1 has been described at pre- and postsynaptic sites, R2 is mainly associated with postsynaptic densities. Different studies have provided valuable information on how these receptors regulate responses at a central level, elucidating different and sometimes synergistic roles in response to stress, but despite their high sequence identity, both receptors have been described to be differentially regulated both by their ligands and by transcriptional factors. To date, and from the point of view of their promoter sequences, it has not yet been reported how the different consensus sites identified in silico could be modulating the transcriptional regulation and expression of the receptors under different conditions, which strongly limits the full understanding of their differential functions, providing a wide field to increase and expand the study of the regulation and role of CRF receptors in the CRF system. SIGNIFICANCE STATEMENT: A large number of physiological functions related to the organization of the stress response in different body tissues are associated with the corticotropin-releasing factor system. This system also plays a relevant role in depression and anxiety disorders, as well as being a direct connection between stress and addiction. A better understanding of how the receptors of this system are regulated would help to expand the understanding of how these receptors respond differently to both drugs and stressful stimuli.
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Affiliation(s)
- Paula Amado
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Zegers
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Hector E Yarur
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Katia Gysling
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
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5
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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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6
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David D, Bentulila Z, Tauber M, Ben-Chaim Y. G Protein-Coupled Receptors Regulated by Membrane Potential. Int J Mol Sci 2022; 23:ijms232213988. [PMID: 36430466 PMCID: PMC9696401 DOI: 10.3390/ijms232213988] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are involved in a vast majority of signal transduction processes. Although they span the cell membrane, they have not been considered to be regulated by the membrane potential. Numerous studies over the last two decades have demonstrated that several GPCRs, including muscarinic, adrenergic, dopaminergic, and glutamatergic receptors, are voltage regulated. Following these observations, an effort was made to elucidate the molecular basis for this regulatory effect. In this review, we will describe the advances in understanding the voltage dependence of GPCRs, the suggested molecular mechanisms that underlie this phenomenon, and the possible physiological roles that it may play.
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7
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Wang X, Yuan S, Chan HCS. Translocation Mechanism of Allosteric Sodium Ions in β 2-Adrenoceptor. J Chem Inf Model 2022; 62:3090-3095. [PMID: 35695388 DOI: 10.1021/acs.jcim.2c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The allosteric modulation of G-protein-coupled receptors (GPCRs) by sodium ions has received significant attention as the crystal structures of several receptors show the binding of sodium ions (Na+) at the conserved D2.50. Theoretical studies have shown that extracellular Na+ would enter the allosteric D2.50 via the orthosteric site. However, it remains unclear how the bound allosteric Na+ would leave the GPCRs. In this study, we performed molecular dynamics (MD) simulations to illustrate the energy barriers of Na+ transfer through the transmembrane helix bundle of β2AR. In contrast to the postulations from other GPCRs, the translocation of this allosteric Na+ into the intracellular side is found to be significantly difficult. Hence, the translocation direction could be receptor-specific.
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Affiliation(s)
- Xueying Wang
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Shuguang Yuan
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.,Alpha Mol Science Ltd, Shenzhen 518055, China
| | - H C Stephen Chan
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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8
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Bueschbell B, Manga P, Schiedel AC. The Many Faces of G Protein-Coupled Receptor 143, an Atypical Intracellular Receptor. Front Mol Biosci 2022; 9:873777. [PMID: 35495622 PMCID: PMC9039016 DOI: 10.3389/fmolb.2022.873777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/10/2022] [Indexed: 12/24/2022] Open
Abstract
GPCRs transform extracellular stimuli into a physiological response by activating an intracellular signaling cascade initiated via binding to G proteins. Orphan G protein-coupled receptors (GPCRs) hold the potential to pave the way for development of new, innovative therapeutic strategies. In this review we will introduce G protein-coupled receptor 143 (GPR143), an enigmatic receptor in terms of classification within the GPCR superfamily and localization. GPR143 has not been assigned to any of the GPCR families due to the lack of common structural motifs. Hence we will describe the most important motifs of classes A and B and compare them to the protein sequence of GPR143. While a precise function for the receptor has yet to be determined, the protein is expressed abundantly in pigment producing cells. Many GPR143 mutations cause X-linked Ocular Albinism Type 1 (OA1, Nettleship-Falls OA), which results in hypopigmentation of the eyes and loss of visual acuity due to disrupted visual system development and function. In pigment cells of the skin, loss of functional GPR143 results in abnormally large melanosomes (organelles in which pigment is produced). Studies have shown that the receptor is localized internally, including at the melanosomal membrane, where it may function to regulate melanosome size and/or facilitate protein trafficking to the melanosome through the endolysosomal system. Numerous additional roles have been proposed for GPR143 in determining cancer predisposition, regulation of blood pressure, development of macular degeneration and signaling in the brain, which we will briefly describe as well as potential ligands that have been identified. Furthermore, GPR143 is a promiscuous receptor that has been shown to interact with multiple other melanosomal proteins and GPCRs, which strongly suggests that this orphan receptor is likely involved in many different physiological actions.
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Affiliation(s)
- Beatriz Bueschbell
- Department of Pharmaceutical and Medicinal Chemistry, Pharmaceutical Institute, University of Bonn, Bonn, Germany
| | - Prashiela Manga
- Ronald O. Perelman Department of Dermatology, Grossman School of Medicine, New York University, New York City, NY, United States
| | - Anke C. Schiedel
- Department of Pharmaceutical and Medicinal Chemistry, Pharmaceutical Institute, University of Bonn, Bonn, Germany
- *Correspondence: Anke C. Schiedel,
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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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10
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Wang LL, Wang HB, Fu FH, Yu LC. Role of calcitonin gene-related peptide in pain regulation in the parabrachial nucleus of naive rats and rats with neuropathic pain. Toxicol Appl Pharmacol 2021; 414:115428. [PMID: 33524449 DOI: 10.1016/j.taap.2021.115428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 01/24/2021] [Accepted: 01/26/2021] [Indexed: 01/14/2023]
Abstract
Researches have shown that calcitonin gene-related peptide (CGRP) plays a pivotal role in pain modulation. Nociceptive information from the periphery is relayed from parabrachial nucleus (PBN) to brain regions implicated involved in pain. This study investigated the effects and mechanisms of CGRP and CGRP receptors in pain regulation in the PBN of naive and neuropathic pain rats. Chronic sciatic nerve ligation was used to model neuropathic pain, CGRP and CGRP 8-37 were injected into the PBN of the rats, and calcitonin receptor-like receptor (CLR), a main structure of CGRP receptor, was knocked down by lentivirus-coated CLR siRNA. The hot plate test (HPT) and the Randall Selitto Test (RST) was used to determine the latency of the rat hindpaw response. The expression of CLR was detected with RT-PCR and western blotting. We found that intra-PBN injecting of CGRP induced an obvious anti-nociceptive effect in naive and neuropathic pain rats in a dose-dependent manner, the CGRP-induced antinociception was significantly reduced after injection of CGRP 8-37, Moreover, the mRNA and protein levels of CLR, in PBN decreased significantly and the antinociception CGRP-induced was also significantly lower in neuropathic pain rats than that in naive rats. Knockdown CLR in PBN decreased the expression of CLR and the antinociception induced by CGRP was observably decreased. Our results demonstrate that CGRP induced antinociception in PBN of naive or neuropathic pain rats, CGRP receptor mediates this effect. Neuropathic pain induced decreases in the expression of CGRP receptor, as well as in CGRP-induced antinociception in PBN.
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Affiliation(s)
- Lin-Lin Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, PR China
| | - Hong-Bo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, PR China
| | - Feng-Hua Fu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, PR China.
| | - Long-Chuan Yu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai 264005, PR China; Neurobiology Laboratory, School of Life Sciences, Peking University, Beijing 100871, PR China.
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11
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Insights into adenosine A2A receptor activation through cooperative modulation of agonist and allosteric lipid interactions. PLoS Comput Biol 2020; 16:e1007818. [PMID: 32298258 PMCID: PMC7188303 DOI: 10.1371/journal.pcbi.1007818] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/28/2020] [Accepted: 03/23/2020] [Indexed: 12/18/2022] Open
Abstract
The activation process of G protein-coupled receptors (GPCRs) has been extensively studied, both experimentally and computationally. In particular, Molecular Dynamics (MD) simulations have proven useful in exploring GPCR conformational space. The typical behaviour of class A GPCRs, when subjected to unbiased MD simulations from their crystallized inactive state, is to fluctuate between inactive and intermediate(s) conformations, even with bound agonist. Fully active conformation(s) are rarely stabilized unless a G protein is also bound. Despite several crystal structures of the adenosine A2a receptor (A2aR) having been resolved in complex with co-crystallized agonists and Gs protein, its agonist-mediated activation process is still not completely understood. In order to thoroughly examine the conformational landscape of A2aR activation, we performed unbiased microsecond-length MD simulations in quadruplicate, starting from the inactive conformation either in apo or with bound agonists: endogenous adenosine or synthetic NECA, embedded in two homogeneous phospholipid membranes: 1,2-dioleoyl-sn-glycerol-3-phosphoglycerol (DOPG) or 1,2-dioleoyl-sn-glycerol-3-phosphocholine (DOPC). In DOPC with bound adenosine or NECA, we observe transition to an intermediate receptor conformation consistent with the known adenosine-bound crystal state. In apo state in DOPG, two different intermediate conformations are obtained. One is similar to that observed with bound adenosine in DOPC, while the other is closer to the active state but not yet fully active. Exclusively, in DOPG with bound adenosine or NECA, we reproducibly identify receptor conformations with fully active features, which are able to dock Gs protein. These different receptor conformations can be attributed to the action/absence of agonist and phospholipid-mediated allosteric effects on the intracellular side of the receptor.
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Kameda H, Yamamoto M, Tone Y, Tone M, Melmed S. Proton Sensitivity of Corticotropin-Releasing Hormone Receptor 1 Signaling to Proopiomelanocortin in Male Mice. Endocrinology 2019; 160:276-291. [PMID: 30535142 PMCID: PMC6324021 DOI: 10.1210/en.2018-00920] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 12/03/2018] [Indexed: 12/20/2022]
Abstract
Because an acidic cellular microenvironment is engendered by inflammation and may determine cell differentiation, we elucidated the impact of acidic conditions on induction of proopiomelanocortin (POMC) expression. Here, we demonstrate mechanisms for proton sensitivity of CRH receptor 1 (CRHR1) signaling to POMC and ACTH production. Low pH (6.8) resulted in doubling of POMC expression and ACTH production in pituitary cell line AtT-20 and in primary mouse pituitary cells. Using CRISPR knockout, we show that CRHR1 is necessary for acid-induced POMC expression, and this induction is mediated by CRHR1 histidine residues and calmodulin-dependent protein kinase II in both pituitary corticotroph cells and in nonpituitary cell lines expressing ectopic ACTH. In contrast, CRH ligand binding affinity to CRHR1 was decreased with acidic pH, implying that proton-induced POMC expression prevails in acidic conditions independently of CRH ligand binding. The results indicate that proton-induced CRHR1 signaling regulates ACTH production in response to an acidic microenvironment.
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Affiliation(s)
- Hiraku Kameda
- Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, California
| | - Masaaki Yamamoto
- Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, California
| | - Yukiko Tone
- Research Division of Immunology, Pacific Heart Lung and Blood Institute, Los Angeles, California
| | - Masahide Tone
- Research Division of Immunology, Pacific Heart Lung and Blood Institute, Los Angeles, California
| | - Shlomo Melmed
- Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, California
- Correspondence: Shlomo Melmed, MD, Room 2015, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, California 90048. E-mail:
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Kondo C, Clark RB, Al‐Jezani N, Kim TY, Belke D, Banderali U, Szerencsei RT, Jalloul AH, Schnetkamp PPM, Spitzer KW, Giles WR. ATP triggers a robust intracellular [Ca 2+ ]-mediated signalling pathway in human synovial fibroblasts. Exp Physiol 2018; 103:1101-1122. [PMID: 29791754 DOI: 10.1113/ep086851] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/26/2018] [Indexed: 01/05/2023]
Abstract
NEW FINDINGS What is the central question of this study? What are the main [Ca2+ ]i signalling pathways activated by ATP in human synovial fibroblasts? What is the main finding and its importance? In human synovial fibroblasts ATP acts through a linked G-protein (Gq ) and phospholipase C signalling mechanism to produce IP3 , which then markedly enhances release of Ca2+ from the endoplasmic reticulum. These results provide new information for the detection of early pathophysiology of arthritis. ABSTRACT In human articular joints, synovial fibroblasts (HSFs) have essential physiological functions that include synthesis and secretion of components of the extracellular matrix and essential articular joint lubricants, as well as release of paracrine substances such as ATP. Although the molecular and cellular processes that lead to a rheumatoid arthritis (RA) phenotype are not fully understood, HSF cells exhibit significant changes during this disease progression. The effects of ATP on HSFs were studied by monitoring changes in intracellular Ca2+ ([Ca2+ ]i ), and measuring electrophysiological properties. ATP application to HSF cell populations that had been enzymatically released from 2-D cell culture revealed that ATP (10-100 μm), or its analogues UTP or ADP, consistently produced a large transient increase in [Ca2+ ]i . These changes (i) were initiated by activation of the P2 Y purinergic receptor family, (ii) required Gq -mediated signal transduction, (iii) did not involve a transmembrane Ca2+ influx, but instead (iv) arose almost entirely from activation of endoplasmic reticulum (ER)-localized inositol 1,4,5-trisphosphate (IP3 ) receptors that triggered Ca2+ release from the ER. Corresponding single cell electrophysiological studies revealed that these ATP effects (i) were insensitive to [Ca2+ ]o removal, (ii) involved an IP3 -mediated intracellular Ca2+ release process, and (iii) strongly turned on Ca2+ -activated K+ current(s) that significantly hyperpolarized these cells. Application of histamine produced very similar effects in these HSF cells. Since ATP is a known paracrine agonist and histamine is released early in the inflammatory response, these findings may contribute to identification of early steps/defects in the initiation and progression of RA.
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Affiliation(s)
- C Kondo
- Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - R B Clark
- Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | | | - T Y Kim
- Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - D Belke
- Cumming School of Medicine, University of Calgary, Calgary, Canada
| | | | - R T Szerencsei
- Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - A H Jalloul
- Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - P P M Schnetkamp
- Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - K W Spitzer
- Nora Eccles Harrison Cardiovascular Centre, Salt Lake City, UT, USA
| | - W R Giles
- Faculty of Kinesiology, University of Calgary, Calgary, Canada.,Faculty of Medicine, University of Calgary, Calgary, Canada
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Zhang XC, Zhou Y, Cao C. Proton transfer during class-A GPCR activation: do the CWxP motif and the membrane potential act in concert? BIOPHYSICS REPORTS 2018. [DOI: 10.1007/s41048-018-0056-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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15
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Barchad-Avitzur O, Priest MF, Dekel N, Bezanilla F, Parnas H, Ben-Chaim Y. A Novel Voltage Sensor in the Orthosteric Binding Site of the M2 Muscarinic Receptor. Biophys J 2017; 111:1396-1408. [PMID: 27705763 DOI: 10.1016/j.bpj.2016.08.035] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 08/28/2016] [Accepted: 08/31/2016] [Indexed: 12/31/2022] Open
Abstract
G protein-coupled receptors (GPCRs) mediate many signal transduction processes in the body. The discovery that these receptors are voltage-sensitive has changed our understanding of their behavior. The M2 muscarinic acetylcholine receptor (M2R) was found to exhibit depolarization-induced charge movement-associated currents, implying that this prototypical GPCR possesses a voltage sensor. However, the typical domain that serves as a voltage sensor in voltage-gated channels is not present in GPCRs, making the search for the voltage sensor in the latter challenging. Here, we examine the M2R and describe a voltage sensor that is comprised of tyrosine residues. This voltage sensor is crucial for the voltage dependence of agonist binding to the receptor. The tyrosine-based voltage sensor discovered here constitutes a noncanonical by which membrane proteins may sense voltage.
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Affiliation(s)
- Ofra Barchad-Avitzur
- Department of Neurobiology, Institute of Life Sciences, The Hebrew University, Jerusalem, Israel
| | - Michael F Priest
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - Noa Dekel
- Department of Neurobiology, Institute of Life Sciences, The Hebrew University, Jerusalem, Israel
| | - Francisco Bezanilla
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - Hanna Parnas
- Department of Neurobiology, Institute of Life Sciences, The Hebrew University, Jerusalem, Israel
| | - Yair Ben-Chaim
- Natural and Life Sciences, Open University of Israel, Raanana, Israel.
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Zia SR, Gaspari R, Decherchi S, Rocchia W. Probing Hydration Patterns in Class-A GPCRs via Biased MD: The A2A Receptor. J Chem Theory Comput 2016; 12:6049-6061. [DOI: 10.1021/acs.jctc.6b00475] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
| | | | - Sergio Decherchi
- BiKi Technologies s.r.l., Via XX Settembre, 33/10, I-16121 Genova, Italy
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Vickery ON, Machtens JP, Tamburrino G, Seeliger D, Zachariae U. Structural Mechanisms of Voltage Sensing in G Protein-Coupled Receptors. Structure 2016; 24:997-1007. [PMID: 27210286 PMCID: PMC4906246 DOI: 10.1016/j.str.2016.04.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/31/2016] [Accepted: 04/04/2016] [Indexed: 12/01/2022]
Abstract
G-protein-coupled receptors (GPCRs) form the largest superfamily of membrane proteins and one-third of all drug targets in humans. A number of recent studies have reported evidence for substantial voltage regulation of GPCRs. However, the structural basis of GPCR voltage sensing has remained enigmatic. Here, we present atomistic simulations on the δ-opioid and M2 muscarinic receptors, which suggest a structural and mechanistic explanation for the observed voltage-induced functional effects. The simulations reveal that the position of an internal Na(+) ion, recently detected to bind to a highly conserved aqueous pocket in receptor crystal structures, strongly responds to voltage changes. The movements give rise to gating charges in excellent agreement with previous experimental recordings. Furthermore, free energy calculations show that these rearrangements of Na(+) can be induced by physiological membrane voltages. Due to its role in receptor function and signal bias, the repositioning of Na(+) has important general implications for signal transduction in GPCRs.
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MESH Headings
- Animals
- Crystallography, X-Ray
- Humans
- Ion Channel Gating
- Models, Molecular
- Molecular Dynamics Simulation
- Protein Binding
- Protein Structure, Secondary
- Receptor, Muscarinic M2/chemistry
- Receptor, Muscarinic M2/metabolism
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Opioid, delta/chemistry
- Receptors, Opioid, delta/metabolism
- Sodium/metabolism
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Affiliation(s)
- Owen N Vickery
- Computational Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK; Physics, School of Science and Engineering, University of Dundee, Nethergate, Dundee DD1 4NH, UK
| | - Jan-Philipp Machtens
- Forschungszentrum Jülich GmbH, Institute of Complex Systems, Zelluläre Biophysik (ICS-4), Leo-Brandt-Strasse, 52428 Jülich, Germany
| | - Giulia Tamburrino
- Computational Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK; Physics, School of Science and Engineering, University of Dundee, Nethergate, Dundee DD1 4NH, UK
| | - Daniel Seeliger
- Lead Identification and Optimization Support, Boehringer Ingelheim Pharma GmbH & Co KG, 88397 Biberach an der Riss, Germany
| | - Ulrich Zachariae
- Computational Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK; Physics, School of Science and Engineering, University of Dundee, Nethergate, Dundee DD1 4NH, UK.
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18
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Zhang XC, Zhou Y, Cao C. Thermodynamics of GPCR activation. BIOPHYSICS REPORTS 2016; 1:115-119. [PMID: 27340689 PMCID: PMC4871901 DOI: 10.1007/s41048-016-0017-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 01/06/2016] [Indexed: 12/30/2022] Open
Affiliation(s)
- Xuejun C Zhang
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
| | - Ye Zhou
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
| | - Can Cao
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China
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19
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Zhang XC, Zhao Y, Heng J, Jiang D. Energy coupling mechanisms of MFS transporters. Protein Sci 2015; 24:1560-79. [PMID: 26234418 DOI: 10.1002/pro.2759] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/27/2015] [Accepted: 07/28/2015] [Indexed: 01/01/2023]
Abstract
Major facilitator superfamily (MFS) is a large class of secondary active transporters widely expressed across all life kingdoms. Although a common 12-transmembrane helix-bundle architecture is found in most MFS crystal structures available, a common mechanism of energy coupling remains to be elucidated. Here, we discuss several models for energy-coupling in the transport process of the transporters, largely based on currently available structures and the results of their biochemical analyses. Special attention is paid to the interaction between protonation and the negative-inside membrane potential. Also, functional roles of the conserved sequence motifs are discussed in the context of the 3D structures. We anticipate that in the near future, a unified picture of the functions of MFS transporters will emerge from the insights gained from studies of the common architectures and conserved motifs.
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Affiliation(s)
- Xuejun C Zhang
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
| | - Yan Zhao
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
| | - Jie Heng
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
| | - Daohua Jiang
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
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Cabana J, Holleran B, Leduc R, Escher E, Guillemette G, Lavigne P. Identification of Distinct Conformations of the Angiotensin-II Type 1 Receptor Associated with the Gq/11 Protein Pathway and the β-Arrestin Pathway Using Molecular Dynamics Simulations. J Biol Chem 2015; 290:15835-15854. [PMID: 25934394 DOI: 10.1074/jbc.m114.627356] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Indexed: 01/14/2023] Open
Abstract
Biased signaling represents the ability of G protein-coupled receptors to engage distinct pathways with various efficacies depending on the ligand used or on mutations in the receptor. The angiotensin-II type 1 (AT1) receptor, a prototypical class A G protein-coupled receptor, can activate various effectors upon stimulation with the endogenous ligand angiotensin-II (AngII), including the Gq/11 protein and β-arrestins. It is believed that the activation of those two pathways can be associated with distinct conformations of the AT1 receptor. To verify this hypothesis, microseconds of molecular dynamics simulations were computed to explore the conformational landscape sampled by the WT-AT1 receptor, the N111G-AT1 receptor (constitutively active and biased for the Gq/11 pathway), and the D74N-AT1 receptor (biased for the β-arrestin1 and -2 pathways) in their apo-forms and in complex with AngII. The molecular dynamics simulations of the AngII-WT-AT1, N111G-AT1, and AngII-N111G-AT1 receptors revealed specific structural rearrangements compared with the initial and ground state of the receptor. Simulations of the D74N-AT1 receptor revealed that the mutation stabilizes the receptor in the initial ground state. The presence of AngII further stabilized the ground state of the D74N-AT1 receptor. The biased agonist [Sar(1),Ile(8)]AngII also showed a preference for the ground state of the WT-AT1 receptor compared with AngII. These results suggest that activation of the Gq/11 pathway is associated with a specific conformational transition stabilized by the agonist, whereas the activation of the β-arrestin pathway is linked to the stabilization of the ground state of the receptor.
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Affiliation(s)
- Jérôme Cabana
- Departments of Pharmacology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4; PROTEO (Quebec Network on Protein Structure, Function, and Engineering), Université Laval, Québec, Québec G1V 0A6, Canada
| | - Brian Holleran
- Departments of Pharmacology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4
| | - Richard Leduc
- Departments of Pharmacology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4
| | - Emanuel Escher
- Departments of Pharmacology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4
| | - Gaétan Guillemette
- Departments of Pharmacology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4
| | - Pierre Lavigne
- PROTEO (Quebec Network on Protein Structure, Function, and Engineering), Université Laval, Québec, Québec G1V 0A6, Canada; Biochemistry, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4.
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Zhang XC, Liu J, Jiang D. Why is dimerization essential for class-C GPCR function? New insights from mGluR1 crystal structure analysis. Protein Cell 2015; 5:492-5. [PMID: 24805307 PMCID: PMC4085282 DOI: 10.1007/s13238-014-0062-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Xuejun C Zhang
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China,
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Zhang XC, Cao C, Zhou Y, Zhao Y. Proton transfer-mediated GPCR activation. Protein Cell 2014; 6:12-7. [PMID: 25319942 PMCID: PMC4286134 DOI: 10.1007/s13238-014-0106-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 09/28/2014] [Indexed: 12/29/2022] Open
Abstract
G-protein coupled receptors (GPCRs) play essential roles in signal transduction from the environment into the cell. While many structural features have been elucidated in great detail, a common functional mechanism on how the ligand-binding signal is converted into a conformational change on the cytoplasmic face resulting in subsequent activation of downstream effectors remain to be established. Based on available structural and functional data of the activation process in class-A GPCRs, we propose here that a change in protonation status, together with proton transfer via conserved structural elements located in the transmembrane region, are the key elements essential for signal transduction across the membrane.
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Affiliation(s)
- Xuejun C Zhang
- National Laboratory of Macromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China,
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