1
|
Reddy KD, Rasool B, Akher FB, Kutlešić N, Pant S, Boudker O. Evolutionary analysis reveals the origin of sodium coupling in glutamate transporters. bioRxiv 2024:2023.12.03.569786. [PMID: 38106174 PMCID: PMC10723334 DOI: 10.1101/2023.12.03.569786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Secondary active membrane transporters harness the energy of ion gradients to concentrate their substrates. Homologous transporters evolved to couple transport to different ions in response to changing environments and needs. The bases of such diversification, and thus principles of ion coupling, are unexplored. Employing phylogenetics and ancestral protein reconstruction, we investigated sodium-coupled transport in prokaryotic glutamate transporters, a mechanism ubiquitous across life domains and critical to neurotransmitter recycling in humans. We found that the evolutionary transition from sodium-dependent to independent substrate binding to the transporter preceded changes in the coupling mechanism. Structural and functional experiments suggest that the transition entailed allosteric mutations, making sodium binding dispensable without affecting ion-binding sites. Allosteric tuning of transporters' energy landscapes might be a widespread route of their functional diversification.
Collapse
Affiliation(s)
- Krishna D. Reddy
- Dept. of Physiology & Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| | - Burha Rasool
- Dept. of Physiology & Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| | - Farideh Badichi Akher
- Dept. of Physiology & Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| | - Nemanja Kutlešić
- Dept. of Physiology & Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| | - Swati Pant
- Dept. of Biochemistry, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| | - Olga Boudker
- Dept. of Physiology & Biophysics, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
- Howard Hughes Medical Institute, Weill Cornell Medical College, 1300 York Ave, New York, NY 10021, USA
| |
Collapse
|
2
|
Prosser RS, Alonzi NA. Discerning conformational dynamics and binding kinetics of GPCRs by 19F NMR. Curr Opin Pharmacol 2023; 72:102377. [PMID: 37612172 DOI: 10.1016/j.coph.2023.102377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/08/2023] [Accepted: 03/13/2023] [Indexed: 08/25/2023]
Abstract
19F NMR provides a way of monitoring conformational dynamics of G-protein coupled receptors (GPCRs) from the perspective of an ensemble. While X-ray crystallography provides exquisitely resolved high-resolution structures of specific states, it generally does not recapitulate the true ensemble of functional states. Fluorine (19F) NMR provides a highly sensitive spectroscopic window into the conformational ensemble, generally permitting the direct quantification of resolvable states. Moreover, straightforward T1- and T2-based relaxation experiments allow for the study of fluctuations within a given state and exchange between states, on timescales spanning nanoseconds to seconds. Conveniently, most biological systems are free of fluorine. Thus, via fluorinated amino acid analogues or thiol-reactive fluorinated tags, F or CF3 reporters can be site specifically incorporated into proteins of interest. In this review, fluorine labeling protocols and 19F NMR experiments will be presented, from the perspective of small molecule NMR (i.e. drug or small molecule interactions with receptors) or macromolecular NMR (i.e. conformational dynamics of receptors and receptor-G-protein complexes).
Collapse
Affiliation(s)
- R S Prosser
- Chemistry Department, University of Toronto, CPS UTM, Davis Building, Rm 4052, 3359 Mississauga Rd North, Mississauga, Ontario, L5L 1C6, Canada; Biochemistry Department, University of Toronto, CPS UTM, Davis Building, Rm 4052, 3359 Mississauga Rd North, Mississauga, Ontario, L5L 1C6, Canada.
| | - Nicholas A Alonzi
- Chemistry Department, University of Toronto, CPS UTM, Davis Building, Rm 4052, 3359 Mississauga Rd North, Mississauga, Ontario, L5L 1C6, Canada
| |
Collapse
|
3
|
Necelis M, McDermott C, Belcher Dufrisne M, Baryiames C, Columbus L. Solution NMR investigations of integral membrane proteins: Challenges and innovations. Curr Opin Struct Biol 2023; 82:102654. [PMID: 37542910 PMCID: PMC10529709 DOI: 10.1016/j.sbi.2023.102654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/08/2023] [Accepted: 06/20/2023] [Indexed: 08/07/2023]
Abstract
Compared to soluble protein counterparts, the understanding of membrane protein stability, solvent interactions, and function are not as well understood. Recent advancements in labeling, expression, and stabilization of membrane proteins have enabled solution nuclear magnetic resonance spectroscopy to investigate membrane protein conformational states, ligand binding, lipid interactions, stability, and folding. This review highlights these advancements and new understandings and provides examples of recent applications.
Collapse
Affiliation(s)
- Matthew Necelis
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Connor McDermott
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | | | | | - Linda Columbus
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA.
| |
Collapse
|
4
|
Wang H, Hu W, Xu T, Yuan Y, Liu D, Wüthrich K. Selective polypeptide ligand binding to the extracellular surface of the transmembrane domains of the class B GPCRs GLP-1R and GCGR. iScience 2023; 26:106918. [PMID: 37332600 PMCID: PMC10276138 DOI: 10.1016/j.isci.2023.106918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/27/2023] [Accepted: 05/14/2023] [Indexed: 06/20/2023] Open
Abstract
Crystal and cryo-EM structures of the glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR) bound with their peptide ligands have been obtained with full-length constructs, indicating that the extracellular domain (ECD) is indispensable for specific ligand binding. This article complements these data with studies of ligand recognition of the two receptors in solution. Paramagnetic NMR relaxation enhancement measurements using dual labeling with fluorine-19 probes on the receptor and nitroxide spin labels on the peptide ligands provided new insights. The glucagon-like peptide-1 (GLP-1) was found to interact with GLP-1R by selective binding to the extracellular surface. The ligand selectivity toward the extracellular surface of the receptor was preserved in the transmembrane domain (TMD) devoid of the ECD. The dual labeling approach further provided evidence of cross-reactivity of GLP-1R and GCGR with glucagon and GLP-1, respectively, which is of interest in the context of medical treatments using combinations of the two polypeptides.
Collapse
Affiliation(s)
- Huixia Wang
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Wanhui Hu
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
| | - Tiandan Xu
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ya Yuan
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
| | - Dongsheng Liu
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
| | - Kurt Wüthrich
- IHuman Institute, ShanghaiTech University, Shanghai 201210, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA 92037, USA
| |
Collapse
|
5
|
Overbeck JH, Vögele J, Nussbaumer F, Duchardt‐Ferner E, Kreutz C, Wöhnert J, Sprangers R. 19F NMR Untersuchung des Konformationsaustauschs mehrerer Zustände im synthetischen Neomycin-bindenden Riboschalter. Angew Chem Weinheim Bergstr Ger 2023; 135:e202218064. [PMID: 38516132 PMCID: PMC10953372 DOI: 10.1002/ange.202218064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Indexed: 03/29/2023]
Abstract
AbstractDer synthetische Neomycin‐bindende Riboschalter interagiert mit seinem Liganden Neomycin sowie mit den verwandten Antibiotika Ribostamycin und Paromomycin. Die Bindung dieser Aminoglykoside induziert sehr ähnliche Grundzustandsstrukturen in der RNA, allerdings kann nur Neomycin die Initiierung der Translation effizient unterdrücken. Der molekulare Ursprung dieser Unterschiede wurde auf Unterschiede in der Dynamik der Ligand‐Riboschalter‐Komplexe zurückgeführt. In diesem Artikel kombinieren wir fünf komplementäre fluorbasierte NMR‐Methoden, um die Dynamik der drei Riboschalter‐Komplexe im Sekunden‐ bis Mikrosekundenbereich genau zu quantifizieren. Unsere Daten offenbaren komplexe Austauschprozesse mit bis zu vier strukturell unterschiedlichen Zuständen. Wir interpretieren unsere Ergebnisse in einem Modell, das ein Zusammenspiel zwischen verschiedenen chemischen Gruppen in den Antibiotika und spezifischen Basen im Riboschalter zeigt. Allgemeiner unterstreichen unsere Daten das Potenzial von 19F NMR‐Methoden, komplexe Austauschprozesse mit mehreren angeregten Zuständen zu charakterisieren.
Collapse
Affiliation(s)
- Jan H. Overbeck
- Department of Biophysics IRegensburg Center for BiochemistryUniversity of RegensburgUniversitätsstrasse 3193051RegensburgDeutschland
| | - Jennifer Vögele
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Deutschland
| | - Felix Nussbaumer
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnsbruckÖsterreich
| | - Elke Duchardt‐Ferner
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Deutschland
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnsbruckÖsterreich
| | - Jens Wöhnert
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Deutschland
| | - Remco Sprangers
- Department of Biophysics IRegensburg Center for BiochemistryUniversity of RegensburgUniversitätsstrasse 3193051RegensburgDeutschland
| |
Collapse
|
6
|
Overbeck JH, Vögele J, Nussbaumer F, Duchardt‐Ferner E, Kreutz C, Wöhnert J, Sprangers R. Multi-Site Conformational Exchange in the Synthetic Neomycin-Sensing Riboswitch Studied by 19 F NMR. Angew Chem Int Ed Engl 2023; 62:e202218064. [PMID: 36970768 PMCID: PMC10952710 DOI: 10.1002/anie.202218064] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/24/2023] [Accepted: 03/22/2023] [Indexed: 03/28/2023]
Abstract
The synthetic neomycin-sensing riboswitch interacts with its cognate ligand neomycin as well as with the related antibiotics ribostamycin and paromomycin. Binding of these aminoglycosides induces a very similar ground state structure in the RNA, however, only neomycin can efficiently repress translation initiation. The molecular origin of these differences has been traced back to differences in the dynamics of the ligand:riboswitch complexes. Here, we combine five complementary fluorine based NMR methods to accurately quantify seconds to microseconds dynamics in the three riboswitch complexes. Our data reveal complex exchange processes with up to four structurally different states. We interpret our findings in a model that shows an interplay between different chemical groups in the antibiotics and specific bases in the riboswitch. More generally, our data underscore the potential of 19 F NMR methods to characterize complex exchange processes with multiple excited states.
Collapse
Affiliation(s)
- Jan H. Overbeck
- Department of Biophysics IRegensburg Center for BiochemistryUniversity of RegensburgUniversitätsstrasse 3193051RegensburgGermany
| | - Jennifer Vögele
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Germany
| | - Felix Nussbaumer
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnsbruckAustria
| | - Elke Duchardt‐Ferner
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Germany
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnsbruckAustria
| | - Jens Wöhnert
- Institute for Molecular BiosciencesGoethe-University FrankfurtMax-von-Laue-Str. 960438Frankfurt/M.Germany
| | - Remco Sprangers
- Department of Biophysics IRegensburg Center for BiochemistryUniversity of RegensburgUniversitätsstrasse 3193051RegensburgGermany
| |
Collapse
|
7
|
Huang Y, Reddy KD, Bracken C, Qiu B, Zhan W, Eliezer D, Boudker O. Environmentally Ultrasensitive Fluorine Probe to Resolve Protein Conformational Ensembles by 19F NMR and Cryo-EM. J Am Chem Soc 2023; 145:8583-8592. [PMID: 37023263 PMCID: PMC10119980 DOI: 10.1021/jacs.3c01003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Indexed: 04/08/2023]
Abstract
Limited chemical shift dispersion represents a significant barrier to studying multistate equilibria of large membrane proteins by 19F NMR. We describe a novel monofluoroethyl 19F probe that dramatically increases the chemical shift dispersion. The improved conformational sensitivity and line shape enable the detection of previously unresolved states in one-dimensional (1D) 19F NMR spectra of a 134 kDa membrane transporter. Changes in the populations of these states in response to ligand binding, mutations, and temperature correlate with population changes of distinct conformations in structural ensembles determined by single-particle cryo-electron microscopy (cryo-EM). Thus, 19F NMR can guide sample preparation to discover and visualize novel conformational states and facilitate image analysis and three-dimensional (3D) classification.
Collapse
Affiliation(s)
- Yun Huang
- Department
of Physiology & Biophysics, Weill Cornell
Medicine, 1300 York Avenue, New York, New York 10021, United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Krishna D. Reddy
- Department
of Physiology & Biophysics, Weill Cornell
Medicine, 1300 York Avenue, New York, New York 10021, United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Clay Bracken
- Department
of Biochemistry, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10021, United States
| | - Biao Qiu
- Department
of Physiology & Biophysics, Weill Cornell
Medicine, 1300 York Avenue, New York, New York 10021, United States
| | - Wenhu Zhan
- Department
of Microbiology & Immunology, Weill
Cornell Medicine, 1300 York Avenue, New York, New York 10021, United States
| | - David Eliezer
- Department
of Biochemistry, Weill Cornell Medicine, 1300 York Avenue, New York, New York 10021, United States
| | - Olga Boudker
- Department
of Physiology & Biophysics, Weill Cornell
Medicine, 1300 York Avenue, New York, New York 10021, United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| |
Collapse
|
8
|
Parigi G, Ravera E, Piccioli M, Luchinat C. Paramagnetic NMR restraints for the characterization of protein structural rearrangements. Curr Opin Struct Biol 2023; 80:102595. [PMID: 37075534 DOI: 10.1016/j.sbi.2023.102595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/15/2023] [Accepted: 03/17/2023] [Indexed: 04/21/2023]
Abstract
Mobility is a common feature of biomacromolecules, often fundamental for their function. Thus, in many cases, biomacromolecules cannot be described by a single conformation, but rather by a conformational ensemble. NMR paramagnetic data demonstrated quite informative to monitor this conformational variability, especially when used in conjunction with data from different sources. Due to their long-range nature, paramagnetic data can, for instance, i) clearly demonstrate the occurrence of conformational rearrangements, ii) reveal the presence of minor conformational states, sampled only for a short time, iii) indicate the most representative conformations within the conformational ensemble sampled by the molecule, iv) provide an upper limit to the weight of each conformation.
Collapse
Affiliation(s)
- Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, Via Sacconi 6, Sesto Fiorentino, 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Via Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, Via Sacconi 6, Sesto Fiorentino, 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Via Sacconi 6, Sesto Fiorentino, 50019, Italy
| | - Mario Piccioli
- Magnetic Resonance Center (CERM), University of Florence, Via Sacconi 6, Sesto Fiorentino, 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Via Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Via Sacconi 6, Sesto Fiorentino, 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Via Sacconi 6, Sesto Fiorentino, 50019, Italy.
| |
Collapse
|
9
|
Abstract
19F NMR has been extensively used in simultaneous analysis of multicomponent due to its 100% natural isotope abundance, high NMR-sensitivity, and wide-range chemical shifts. The solvent effects are usually observed in NMR spectroscopy and cause large changes in 19F chemical shifts. Herein, we propose that the simultaneous analysis of a complex mixture can be achieved using solvent effects via 19F NMR spectroscopy, such as a mixture solution of amino acids (AAs). AAs are not only cell-signaling molecules, but are also considered as biomarkers of some diseases. Hence, the analysis of AAs is important for human health and the diagnosis of diseases. In this work, the key to the success of sensing 19 biogenic AAs is the use of 2-fluorobenzaldehyde (2FBA) as a highly sensitive derivatizing agent and solvent effects to produce distinguishable 19F NMR signals. As a result, the resolution of 19F NMR spectroscopy of multiple 2FBA-labeled AAs is obviously higher than other methods based on 19F NMR. Moreover, 14 and 18 AAs can be satisfactorily differentiated and unambiguously identified in different complicated media supporting the growth of mammalian cells. Furthermore, quantification of the concentration of AAs can be made, and the limit of detection reaches 10 μM. Our work provides new insights into the simultaneous analysis of a multicomponent mixture based on solvent effects by 19F NMR spectroscopy.
Collapse
Affiliation(s)
- Lihua Xu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, 315211, P.R. China
| | - Biling Huang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, 315211, P.R. China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, 315211, P.R. China
| | - Zhiying Hou
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, 315211, P.R. China
| | - Shaohua Huang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, 315211, P.R. China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, 315211, P.R. China
| | - Yufen Zhao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, 315211, P.R. China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, 315211, P.R. China.,Department of Chemical Biology, College of Chemistry and Chemical Engineering, and the Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen, 361005, P.R. China.,Key Lab of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, P.R. China
| |
Collapse
|
10
|
Khananshvili D. Structure-Based Function and Regulation of NCX Variants: Updates and Challenges. Int J Mol Sci 2022; 24. [PMID: 36613523 DOI: 10.3390/ijms24010061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
The plasma-membrane homeostasis Na+/Ca2+ exchangers (NCXs) mediate Ca2+ extrusion/entry to dynamically shape Ca2+ signaling/in biological systems ranging from bacteria to humans. The NCX gene orthologs, isoforms, and their splice variants are expressed in a tissue-specific manner and exhibit nearly 104-fold differences in the transport rates and regulatory specificities to match the cell-specific requirements. Selective pharmacological targeting of NCX variants could benefit many clinical applications, although this intervention remains challenging, mainly because a full-size structure of eukaryotic NCX is unavailable. The crystal structure of the archaeal NCX_Mj, in conjunction with biophysical, computational, and functional analyses, provided a breakthrough in resolving the ion transport mechanisms. However, NCX_Mj (whose size is nearly three times smaller than that of mammalian NCXs) cannot serve as a structure-dynamic model for imitating high transport rates and regulatory modules possessed by eukaryotic NCXs. The crystal structures of isolated regulatory domains (obtained from eukaryotic NCXs) and their biophysical analyses by SAXS, NMR, FRET, and HDX-MS approaches revealed structure-based variances of regulatory modules. Despite these achievements, it remains unclear how multi-domain interactions can decode and integrate diverse allosteric signals, thereby yielding distinct regulatory outcomes in a given ortholog/isoform/splice variant. This article summarizes the relevant issues from the perspective of future developments.
Collapse
|
11
|
Chen I, Wu Q, Font J, Ryan RM. The twisting elevator mechanism of glutamate transporters reveals the structural basis for the dual transport-channel functions. Curr Opin Struct Biol 2022; 75:102405. [PMID: 35709614 DOI: 10.1016/j.sbi.2022.102405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 11/16/2022]
Abstract
Glutamate transporters facilitate the removal of this excitatory neurotransmitter from the synapse. Increasing evidence indicates that this process is linked to intrinsic chloride channel activity that is thermodynamically uncoupled from substrate transport. A recent cryo-EM structure of GltPh - an archaeal homolog of the glutamate transporters - in an open channel state has shed light on the structural basis for channel opening formed at the interface of two domains within the transporter which is gated by two clusters of hydrophobic residues. These transporters cycle through several conformational states during the transport process, including the chloride conducting state, which appears to be stabilised by protein-membrane interactions and membrane deformation. Several point mutations that perturb the chloride conductance can have detrimental effects and are linked to the pathogenesis of the neurological disorder, episodic ataxia type 6.
Collapse
Affiliation(s)
- Ichia Chen
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, NSW, Australia
| | - Qianyi Wu
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, NSW, Australia
| | - Josep Font
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, NSW, Australia
| | - Renae M Ryan
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, NSW, Australia.
| |
Collapse
|
12
|
Zhu W, Guseman AJ, Bhinderwala F, Lu M, Su XC, Gronenborn AM. Visualizing Proteins in Mammalian Cells by 19 F NMR Spectroscopy. Angew Chem Int Ed Engl 2022; 61:e202201097. [PMID: 35278268 PMCID: PMC9156538 DOI: 10.1002/anie.202201097] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Indexed: 12/20/2022]
Abstract
In-cell NMR spectroscopy is a powerful tool to investigate protein behavior in physiologically relevant environments. Although proven valuable for disordered proteins, we show that in commonly used 1 H-15 N HSQC spectra of globular proteins, interactions with cellular components often broaden resonances beyond detection. This contrasts 19 F spectra in mammalian cells, in which signals are readily observed. Using several proteins, we demonstrate that surface charges and interaction with cellular binding partners modulate linewidths and resonance frequencies. Importantly, we establish that 19 F paramagnetic relaxation enhancements using stable, rigid Ln(III) chelate pendants, attached via non-reducible thioether bonds, provide an effective means to obtain accurate distances for assessing protein conformations in the cellular milieu.
Collapse
Affiliation(s)
- Wenkai Zhu
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, USA.,Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA 15261, USA
| | - Alex J Guseman
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, USA
| | - Fatema Bhinderwala
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, USA
| | - Manman Lu
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, USA.,Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA 15261, USA
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 300071, Tianjin, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, 300071, Tianjin, China
| | - Angela M Gronenborn
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, USA.,Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA 15261, USA
| |
Collapse
|
13
|
Parigi G, Ravera E, Luchinat C. Paramagnetic effects in NMR for protein structures and ensembles: Studies of metalloproteins. Curr Opin Struct Biol 2022; 74:102386. [DOI: 10.1016/j.sbi.2022.102386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/29/2022] [Accepted: 04/07/2022] [Indexed: 11/28/2022]
|
14
|
Reddy KD, Ciftci D, Scopelliti AJ, Boudker O. The archaeal glutamate transporter homologue GltPh shows heterogeneous substrate binding. J Gen Physiol 2022; 154:213177. [PMID: 35452090 PMCID: PMC9044058 DOI: 10.1085/jgp.202213131] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 03/10/2022] [Indexed: 12/31/2022] Open
Abstract
Integral membrane glutamate transporters couple the concentrative substrate transport to ion gradients. There is a wealth of structural and mechanistic information about this protein family. Recent studies of an archaeal homologue, GltPh, revealed transport rate heterogeneity, which is inconsistent with simple kinetic models; however, its structural and mechanistic determinants remain undefined. Here, we demonstrate that in a mutant GltPh, which exclusively populates the outward-facing state, at least two substates coexist in slow equilibrium, binding the substrate with different apparent affinities. Wild type GltPh shows similar binding properties, and modulation of the substate equilibrium correlates with transport rates. The low-affinity substate of the mutant is transient following substrate binding. Consistently, cryo-EM on samples frozen within seconds after substrate addition reveals the presence of structural classes with perturbed helical packing of the extracellular half of the transport domain in regions adjacent to the binding site. By contrast, an equilibrated structure does not show such classes. The structure at 2.2-Å resolution details a pattern of waters in the intracellular half of the domain and resolves classes with subtle differences in the substrate-binding site. We hypothesize that the rigid cytoplasmic half of the domain mediates substrate and ion recognition and coupling, whereas the extracellular labile half sets the affinity and dynamic properties.
Collapse
Affiliation(s)
- Krishna D Reddy
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY
| | - Didar Ciftci
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY.,Tri-Institutional Training Program in Chemical Biology, New York, NY
| | - Amanda J Scopelliti
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY
| | - Olga Boudker
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY.,Howard Hughes Medical Institute, Weill Cornell Medicine, New York, NY
| |
Collapse
|
15
|
Huang B, Xu L, Zhao Z, Wang N, Zhao Y, Huang S. Simultaneous analysis of amino acids based on discriminative 19F NMR spectroscopy. Bioorg Chem 2022; 124:105818. [PMID: 35489271 DOI: 10.1016/j.bioorg.2022.105818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/14/2022] [Accepted: 04/16/2022] [Indexed: 11/02/2022]
Abstract
The simultaneous analysis of amino acids (AAs) is crucial for human health, diagnosis and treatment of disease, and nutritional quality evaluation in foodstuffs. Here, we establish an easy and rapid method for the simultaneous analysis of AAs using a single reagent 2-(trifluoromethyl)benzaldehyde (oTFMBA) based on spectral-separation-enabled 19F NMR spectroscopy. oTFMBA, a highly sensitive chemosensor, is capable of analyzing 19 proteinogenic AAs or non-amino acid amines (non-AAs) in a complex mixture by adjusting the pH in a toilless way. The 19F signals of oTFMBA-labeled AAs are distributed over a wide range of ∼ 0.7 ppm, demonstrating oTFMBA with higher resolution for simultaneous analysis of AAs compared to the o-phthaldialdehyde (OPA) method (<0.6 ppm). Additionally, 12 AAs were unambiguously identified in human urine, including Asp, Ser, Gly, Thr, Glu, Arg, Ala, Val, Ile, Tyr, His, and Phe. Furthermore, our method's detection limit for AAs is 5.83 μM, illustrating sensitivity with an ∼100-fold improvement over the OPA method. This work represents an approach to the analysis of AAs or non-AAs in a complicated mixture (even biofluid) using a 19F NMR probe with high sensitivity, which is of great significance for the simultaneous analysis of multiple analytes.
Collapse
Affiliation(s)
- Biling Huang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China; Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, Zhejiang, PR China.
| | - Lihua Xu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China
| | - Zhao Zhao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China
| | - Ning Wang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China; Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, Zhejiang, PR China
| | - Yufen Zhao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China; Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, Zhejiang, PR China; Department of Chemical Biology, College of Chemistry and Chemical Engineering, and the Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen 361005, PR China; Key Lab of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 100084, PR China
| | - Shaohua Huang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, PR China; Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, Zhejiang, PR China.
| |
Collapse
|
16
|
Gronenborn AM, Zhu W, Guseman AJ, Bhinderwala F, Lu M, Su XC. Visualizing Proteins in Mammalian Cells by 19F NMR spectroscopy. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Angela M Gronenborn
- University of Pittsburgh, School of Medicine Department of Structural Biology 3501 Fifth AvenueBiomedical Science Tower 3 15260 Pittsburgh UNITED STATES
| | - Wenkai Zhu
- University of Pittsburgh School of Medicine Department of Structural Biology 3501 Fifth AvenueBiomedical Science Tower 3 15260 Pittsburgh UNITED STATES
| | - Alex J Guseman
- University of Pittsburgh School of Medicine Department of Structural Biology 3501 Fifth AvenueBiomedical Science Tower 3 15260 Pittsburgh UNITED STATES
| | - Fatema Bhinderwala
- University of Pittsburgh School of Medicine Department of Structural Biology UNITED STATES
| | - Manman Lu
- University of Pittsburgh School of Medicine Department of Structural Biology 3501 Fifth AvenueBiomedical Science Tower 3 15260 Pittsburgh UNITED STATES
| | - Xun-Cheng Su
- Nankai University College of Chemistry State Key Laboratory of Elemento-Organic Chemistry 300071 Tianjin CHINA
| |
Collapse
|
17
|
Puthenveetil R, Christenson ET, Vinogradova O. New Horizons in Structural Biology of Membrane Proteins: Experimental Evaluation of the Role of Conformational Dynamics and Intrinsic Flexibility. Membranes (Basel) 2022; 12:227. [PMID: 35207148 PMCID: PMC8877495 DOI: 10.3390/membranes12020227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 02/08/2023]
Abstract
A plethora of membrane proteins are found along the cell surface and on the convoluted labyrinth of membranes surrounding organelles. Since the advent of various structural biology techniques, a sub-population of these proteins has become accessible to investigation at near-atomic resolutions. The predominant bona fide methods for structure solution, X-ray crystallography and cryo-EM, provide high resolution in three-dimensional space at the cost of neglecting protein motions through time. Though structures provide various rigid snapshots, only an amorphous mechanistic understanding can be inferred from interpolations between these different static states. In this review, we discuss various techniques that have been utilized in observing dynamic conformational intermediaries that remain elusive from rigid structures. More specifically we discuss the application of structural techniques such as NMR, cryo-EM and X-ray crystallography in studying protein dynamics along with complementation by conformational trapping by specific binders such as antibodies. We finally showcase the strength of various biophysical techniques including FRET, EPR and computational approaches using a multitude of succinct examples from GPCRs, transporters and ion channels.
Collapse
Affiliation(s)
- Robbins Puthenveetil
- Section on Structural and Chemical Biology of Membrane Proteins, Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 35A Convent Dr., Bethesda, MD 20892, USA
| | | | - Olga Vinogradova
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, CT 06269, USA
| |
Collapse
|
18
|
Gronenborn AM. Small, but powerful and attractive: 19F in biomolecular NMR. Structure 2022; 30:6-14. [PMID: 34995480 PMCID: PMC8797020 DOI: 10.1016/j.str.2021.09.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/03/2021] [Accepted: 09/20/2021] [Indexed: 01/09/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a versatile tool for probing structure, dynamics, folding, and interactions at atomic resolution. While naturally occurring magnetically active isotopes, such as 1H, 13C, or 15N, are most commonly used in biomolecular NMR, with 15N and 13C isotopic labeling routinely employed at the present time, 19F is a very attractive and sensitive alternative nucleus, which offers rich information on biomolecules in solution and in the solid state. This perspective summarizes the unique benefits of solution and solid-state 19F NMR spectroscopy for the study of biological systems. Particular focus is on the most recent studies and on future unique and important potential applications of fluorine NMR methodology.
Collapse
|
19
|
Asanbaeva N, Sukhanov A, Diveikina AA, Rogozhnikova O, Trukhin DV, Tormyshev VM, Chubarov AS, Maryasov AG, Genaev A, Shernyukov AV, Salnikov GE, Lomzov AA, Pyshnyi DV, Bagryanskaya E. Application of W-band 19F electron nuclear double resonance (ENDOR) spectroscopy to distance measurement using a trityl spin probe and a fluorine label. Phys Chem Chem Phys 2022; 24:5982-6001. [DOI: 10.1039/d1cp05445g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recently, Marina Bennati and coworkers (Angew. Chemie - Int. Ed., 2020, 59, 373–379., A. J. Magn. Reson., 2021, 333, 107091) proposed to use electron nuclear double resonance (ENDOR) spectroscopy in...
Collapse
|
20
|
Abstract
Uncovering the structure and function of biomolecules is a fundamental goal in structural biology. Membrane-embedded transport proteins are ubiquitous in all kingdoms of life. Despite structural flexibility, their mechanisms are typically studied by ensemble biochemical methods or by static high-resolution structures, which complicate a detailed understanding of their dynamics. Here, we review the recent progress of single molecule Förster Resonance Energy Transfer (smFRET) in determining mechanisms and timescales of substrate transport across membranes. These studies do not only demonstrate the versatility and suitability of state-of-the-art smFRET tools for studying membrane transport proteins but they also highlight the importance of membrane mimicking environments in preserving the function of these proteins. The current achievements advance our understanding of transport mechanisms and have the potential to facilitate future progress in drug design.
Collapse
Affiliation(s)
- Kim Bartels
- Centre for Structural Systems Biology (CSSB)DESY and European Molecular Biology Laboratory HamburgNotkestrasse 8522607HamburgGermany
| | - Tanya Lasitza‐Male
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Hagen Hofmann
- Department of Structural BiologyWeizmann Institute of ScienceHerzl St. 2347610001RehovotIsrael
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB)DESY and European Molecular Biology Laboratory HamburgNotkestrasse 8522607HamburgGermany
| |
Collapse
|
21
|
Picard LP, Prosser RS. Advances in the study of GPCRs by 19F NMR. Curr Opin Struct Biol 2021; 69:169-176. [PMID: 34130235 DOI: 10.1016/j.sbi.2021.05.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/18/2021] [Accepted: 05/10/2021] [Indexed: 02/07/2023]
Abstract
Crystallography and cryo-electron microscopy have advanced atomic resolution perspectives of inactive and active states of G protein-coupled receptors (GPCRs), alone and in complex with G proteins or arrestin. 19F NMR can play a role in ascertaining activation mechanisms and understanding the complete energy landscape associated with signal transduction. Fluorinated reporters are introduced biosynthetically via fluorinated amino acid analogs or chemically, via thiol-specific fluorinated reporters. The chemical shift sensitivity of these reporters makes it possible to discern details of conformational ensembles. In addition to spectroscopic details, paramagnetic species can be incorporated through orthogonal techniques to obtain distance information on fluorinated reporters, while T2-and T1-based relaxation experiments provide details on exchange kinetics in addition to fluctuations within a given state.
Collapse
|
22
|
Chen JL, Chen BG, Li B, Yang F, Su XC. Assessing multiple conformations of lanthanide binding tags for proteins using a sensitive 19F-reporter. Chem Commun (Camb) 2021; 57:4291-4294. [PMID: 33913982 DOI: 10.1039/d1cc00791b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Quantifying the isomeric species of metal complexes in solution is difficult. 19F NMR herein was used to determine the abundance of isomeric species and dynamic properties of lanthanide binding tags. The results suggest that 19F is an efficient reporter in assessing and screening paramagnetic tags suitable for protein NMR analysis.
Collapse
Affiliation(s)
- Jia-Liang Chen
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| | - Ben-Guang Chen
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| | - Bin Li
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| | - Feng Yang
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| |
Collapse
|
23
|
Le Bon C, Michon B, Popot JL, Zoonens M. Amphipathic environments for determining the structure of membrane proteins by single-particle electron cryo-microscopy. Q Rev Biophys 2021; 54:e6. [PMID: 33785082 DOI: 10.1017/S0033583521000044] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Over the past decade, the structural biology of membrane proteins (MPs) has taken a new turn thanks to epoch-making technical progress in single-particle electron cryo-microscopy (cryo-EM) as well as to improvements in sample preparation. The present analysis provides an overview of the extent and modes of usage of the various types of surfactants for cryo-EM studies. Digitonin, dodecylmaltoside, protein-based nanodiscs, lauryl maltoside-neopentyl glycol, glyco-diosgenin, and amphipols (APols) are the most popular surfactants at the vitrification step. Surfactant exchange is frequently used between MP purification and grid preparation, requiring extensive optimization each time the study of a new MP is undertaken. The variety of both the surfactants and experimental approaches used over the past few years bears witness to the need to continue developing innovative surfactants and optimizing conditions for sample preparation. The possibilities offered by novel APols for EM applications are discussed.
Collapse
|
24
|
Abstract
During the past decades, solution nuclear magnetic resonance (NMR) spectroscopy has demonstrated itself as a promising tool in drug discovery. Especially, fragment-based drug discovery (FBDD) has benefited a lot from the NMR development. Multiple candidate compounds and FDA-approved drugs derived from FBDD have been developed with the assistance of NMR techniques. NMR has broad applications in different stages of the FBDD process, which includes fragment library construction, hit generation and validation, hit-to-lead optimization and working mechanism elucidation, etc. In this manuscript, we reviewed the current progresses of NMR applications in fragment-based drug discovery, which were illustrated by multiple reported cases. Moreover, the NMR applications in protein-protein interaction (PPI) modulators development and the progress of in-cell NMR for drug discovery were also briefly summarized.
Collapse
|
25
|
Overbeck JH, Kremer W, Sprangers R. A suite of 19F based relaxation dispersion experiments to assess biomolecular motions. J Biomol NMR 2020; 74:753-766. [PMID: 32997265 PMCID: PMC7701166 DOI: 10.1007/s10858-020-00348-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/18/2020] [Indexed: 05/08/2023]
Abstract
Proteins and nucleic acids are highly dynamic bio-molecules that can populate a variety of conformational states. NMR relaxation dispersion (RD) methods are uniquely suited to quantify the associated kinetic and thermodynamic parameters. Here, we present a consistent suite of 19F-based CPMG, on-resonance R1ρ and off-resonance R1ρ RD experiments. We validate these experiments by studying the unfolding transition of a 7.5 kDa cold shock protein. Furthermore we show that the 19F RD experiments are applicable to very large molecular machines by quantifying dynamics in the 360 kDa half-proteasome. Our approach significantly extends the timescale of chemical exchange that can be studied with 19F RD, adds robustness to the extraction of exchange parameters and can determine the absolute chemical shifts of excited states. Importantly, due to the simplicity of 19F NMR spectra, it is possible to record complete datasets within hours on samples that are of very low costs. This makes the presented experiments ideally suited to complement static structural information from cryo-EM and X-ray crystallography with insights into functionally relevant motions.
Collapse
Affiliation(s)
- Jan H Overbeck
- Department of Biophysics I, Regensburg Center for Biochemistry, University of Regensburg, 93053, Regensburg, Germany
| | - Werner Kremer
- Department of Biophysics I, Regensburg Center for Biochemistry, University of Regensburg, 93053, Regensburg, Germany
| | - Remco Sprangers
- Department of Biophysics I, Regensburg Center for Biochemistry, University of Regensburg, 93053, Regensburg, Germany.
| |
Collapse
|
26
|
Matin TR, Heath GR, Huysmans GHM, Boudker O, Scheuring S. Millisecond dynamics of an unlabeled amino acid transporter. Nat Commun 2020; 11:5016. [PMID: 33024106 PMCID: PMC7538599 DOI: 10.1038/s41467-020-18811-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/16/2020] [Indexed: 12/14/2022] Open
Abstract
Excitatory amino acid transporters (EAATs) are important in many physiological processes and crucial for the removal of excitatory amino acids from the synaptic cleft. Here, we develop and apply high-speed atomic force microscopy line-scanning (HS-AFM-LS) combined with automated state assignment and transition analysis for the determination of transport dynamics of unlabeled membrane-reconstituted GltPh, a prokaryotic EAAT homologue, with millisecond temporal resolution. We find that GltPh transporters can operate much faster than previously reported, with state dwell-times in the 50 ms range, and report the kinetics of an intermediate transport state with height between the outward- and inward-facing states. Transport domains stochastically probe transmembrane motion, and reversible unsuccessful excursions to the intermediate state occur. The presented approach and analysis methodology are generally applicable to study transporter kinetics at system-relevant temporal resolution. Excitatory amino acid transporters (EAATs) are crucial for the removal of excitatory amino acids from the synaptic cleft. Here authors combined high-speed atomic force microscopy line-scanning with automated state assignment for the determination of transport dynamics of GltPh, a prokaryotic EAAT homologue, with millisecond temporal resolution.
Collapse
Affiliation(s)
- Tina R Matin
- Department of Anesthesiology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.,Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - George R Heath
- Department of Anesthesiology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.,Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Gerard H M Huysmans
- Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Olga Boudker
- Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.,Howard Hughes Medical Institute, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Simon Scheuring
- Department of Anesthesiology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA. .,Department of Physiology and Biophysics, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.
| |
Collapse
|
27
|
Cheng RC, Maduke M. Expanding the membrane-protein NMR toolkit. Nat Chem Biol 2020; 16:937-938. [PMID: 32665639 PMCID: PMC8064024 DOI: 10.1038/s41589-020-0597-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An NMR method to monitor conformational states of challenging large protein targets is described. The method, which can be used to evaluate distances between two labels and to measure conformational exchange rates, revealed an unanticipated outward-facing state in a glutamate transporter.
Collapse
Affiliation(s)
- Ricky C Cheng
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Merritt Maduke
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.
| |
Collapse
|
28
|
Wang X, Boudker O. Large domain movements through the lipid bilayer mediate substrate release and inhibition of glutamate transporters. eLife 2020; 9:58417. [PMID: 33155546 PMCID: PMC7682989 DOI: 10.7554/elife.58417] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/05/2020] [Indexed: 01/21/2023] Open
Abstract
Glutamate transporters are essential players in glutamatergic neurotransmission in the brain, where they maintain extracellular glutamate below cytotoxic levels and allow for rounds of transmission. The structural bases of their function are well established, particularly within a model archaeal homolog, sodium, and aspartate symporter GltPh. However, the mechanism of gating on the cytoplasmic side of the membrane remains ambiguous. We report Cryo-EM structures of GltPh reconstituted into nanodiscs, including those structurally constrained in the cytoplasm-facing state and either apo, bound to sodium ions only, substrate, or blockers. The structures show that both substrate translocation and release involve movements of the bulky transport domain through the lipid bilayer. They further reveal a novel mode of inhibitor binding and show how solutes release is coupled to protein conformational changes. Finally, we describe how domain movements are associated with the displacement of bound lipids and significant membrane deformations, highlighting the potential regulatory role of the bilayer.
Collapse
Affiliation(s)
- Xiaoyu Wang
- Department of Physiology and Biophysics, Weill Cornell MedicineNew YorkUnited States
| | - Olga Boudker
- Department of Physiology and Biophysics, Weill Cornell MedicineNew YorkUnited States,Howard Hughes Medical InstituteChevy ChaseUnited States
| |
Collapse
|