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Molecular and Functional Interactions of Alpha-Synuclein with Rab3a. J Biol Chem 2022; 298:102239. [PMID: 35809645 PMCID: PMC9396396 DOI: 10.1016/j.jbc.2022.102239] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 11/23/2022] Open
Abstract
Alpha-synuclein (a-Syn) is a presynaptic protein, the misfolding of which is associated with Parkinson’s disease. Rab GTPases are small guanine nucleotide binding proteins that play key roles in vesicle trafficking and have been associated with a-Syn function and dysfunction. a-Syn is enriched on synaptic vesicles, where it has been reported to interact with GTP-bound Rab3a, a master regulator of synaptic vesicle trafficking. a-Syn is known to bind weakly to Rab8a in solution via a positively charged patch, but the physiological implications of such interactions have not been explored. Here, we investigate direct interactions between a-Syn and Rab3a in solution and on lipid membranes using NMR spectroscopy. We find that the C terminus of a-Syn interacts with Rab3a in a manner similar to its previously reported interaction with Rab8a. While weak in solution, we demonstrate that this interaction becomes stronger when the proteins are bound to a membrane surface. The Rab3a binding site for a-Syn is similar to the surface that contacts the Rab3a effector rabphilin-3A, which modulates the enzymatic activity of Rab3a. Accordingly, we show that a-Syn inhibits GTP hydrolysis by Rab3a and that inhibition is more potent on the membrane surface, suggesting that their interaction may be functionally relevant. Finally, we show that phosphorylation of a-Syn residue Ser 129, a modification associated with Parkinson’s disease pathology, enhances its interactions with Rab3a and increases its ability to inhibit Rab3a GTP hydrolysis. These results represent the first observation of a functional role for synuclein-Rab interactions and for a-Syn Ser 129 phosphorylation.
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2
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Tillman TS, Choi Z, Xu Y, Tang P. Functional Tolerance to Cysteine Mutations in Human α7 Nicotinic Acetylcholine Receptors. ACS Chem Neurosci 2020; 11:242-247. [PMID: 31951367 DOI: 10.1021/acschemneuro.9b00647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor (α7 nAChR) is involved in various intracellular signaling pathways that mediate addiction, chronic pain, and other diseases, but its intracellular domain structures remain undetermined. The presence of 17 native cysteines in α7 nAChR provides opportunities for extracting structural information through site-directed labeling of chemical probes in strategic locations, but it also creates uncertainties in channel function when those native cysteines must be mutated. Using site-directed mutagenesis and two-electrode voltage clamp electrophysiology measurements, we found that α7 nAChR's function was well tolerated for mutations of all 13 cysteines as long as two pairs of disulfide-bond cysteines remained in the extracellular domain. Furthermore, surface plasmon resonance measurements showed that the cysteine mutations did not affect α7 nAChR binding to the intracellular protein PICK1. The study suggests that a high native cysteine content does not necessarily preclude the use of single cysteine labeling for acquiring structural information on functional proteins.
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Affiliation(s)
- Tommy S. Tillman
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Zachary Choi
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Yan Xu
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Pei Tang
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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3
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Das T, Acosta D, Eliezer D. Interactions of IDPs with Membranes Using Dark-State Exchange NMR Spectroscopy. Methods Mol Biol 2020; 2141:585-608. [PMID: 32696379 PMCID: PMC8185907 DOI: 10.1007/978-1-0716-0524-0_30] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Membrane interactions of proteins play a role in essential cellular processes in both physiological and disease states. The structural flexibility of intrinsically disordered proteins (IDPs) allows for interactions with multiple partners, including membranes. However, determining conformational states of IDPs when interacting with membranes can be challenging. Here we describe the use of nuclear magnetic resonance (NMR), including dark-state exchange saturation transfer (DEST), to probe IDP-membrane interactions in order to determine whether there is an interaction, which residues participate, and the extent/nature of the interaction between the protein and the membrane. Using α-synuclein and tau as typical examples, we provide protocols for how the membrane interactions of IDPs can be probed, including details of how the samples should be prepared and guidelines on how to interpret the results.
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Affiliation(s)
- Tapojyoti Das
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA
- Brain and Mind Research Institute,, Weill Cornell Medical College of Cornell University, New York, NY, USA
| | - Diana Acosta
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA
- Brain and Mind Research Institute,, Weill Cornell Medical College of Cornell University, New York, NY, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA.
- Brain and Mind Research Institute,, Weill Cornell Medical College of Cornell University, New York, NY, USA.
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4
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Acosta D, Das T, Eliezer D. Probing IDP Interactions with Membranes by Fluorescence Spectroscopy. Methods Mol Biol 2020; 2141:555-567. [PMID: 32696377 DOI: 10.1007/978-1-0716-0524-0_28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The microtubule-associated protein tau has been extensively studied as a culprit in Alzheimer's disease and other neurodegenerative diseases known as tauopathies. Challenges in structurally defining tau protein emerge from its disordered nature, which makes it difficult to crystallize, and hinder efforts to interpret tau protein's true function. The complexity of intrinsically disordered proteins (IDPs) necessitates a multifaceted approach to study their interactions including multiple spectroscopic methods that can report on local protein environment and structure at individual residue positions. We and others have shown that in addition to binding to microtubules, tau binds to lipid membranes. Tau-membrane interactions may be relevant both to normal tau function and to tau aggregation and pathology. Here we describe the use of fluorescence spectroscopy as a probe of protein-membrane interactions to determine whether there is an interaction, which residues participate, and the extent/nature of the interface between the protein and the membrane. We provide a protocol for how the membrane interactions of tau protein, as an example, can be probed by fluorescence spectroscopy, including details of how the samples should be prepared and guidelines on how to interpret the results.
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Affiliation(s)
- Diana Acosta
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA.,Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY, USA
| | - Tapojyoti Das
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA.,Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medical College of Cornell University, New York, NY, USA. .,Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY, USA.
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5
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Bondarenko V, Wells MM, Chen Q, Singewald KC, Saxena S, Xu Y, Tang P. 19F Paramagnetic Relaxation-Based NMR for Quaternary Structural Restraints of Ion Channels. ACS Chem Biol 2019; 14:2160-2165. [PMID: 31525026 DOI: 10.1021/acschembio.9b00692] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quaternary distance restraints are essential to define the three-dimensional structures of protein assemblies. These distances often fall within a range of 10-18 Å, which challenges the high and low measurement limits of conventional nuclear magnetic resonance (NMR) and double electron-electron resonance electron spin resonance spectroscopies. Here, we report the use of 19F paramagnetic relaxation enhancement (PRE) NMR in combination with 19F/paramagnetic labeling to equivalent sites in different subunits of a protein complex in micelles to determine intersubunit distances. The feasibility of this strategy was evaluated on a pentameric ligand-gated ion channel, for which we found excellent agreement of the 19F PRE NMR results with previous structural information. The study suggests that 19F PRE NMR is a viable tool in extracting distance restraints to define quaternary structures.
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Affiliation(s)
- Vasyl Bondarenko
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Marta M. Wells
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Qiang Chen
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Kevin C. Singewald
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Yan Xu
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Pei Tang
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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6
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Membrane interactions of intrinsically disordered proteins: The example of alpha-synuclein. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:879-889. [PMID: 31096049 DOI: 10.1016/j.bbapap.2019.05.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 05/03/2019] [Accepted: 05/08/2019] [Indexed: 12/11/2022]
Abstract
Peripheral membrane proteins associate reversibly with biological membranes that, compared to protein binding partners, are structurally labile and devoid of specific binding pockets. Membranes in different subcellular compartments vary primarily in their chemical composition and physical properties, and recognition of these features is therefore critical for allowing such proteins to engage their proper membrane targets. Intrinsically disordered proteins (IDPs) are well-suited to accomplish this task using highly specific and low- to moderate-affinity interactions governed by recognition principles that are both similar to and different from those that mediate the membrane interactions of rigid proteins. IDPs have also evolved multiple mechanisms to regulate membrane (and other) interactions and achieve their impressive functional diversity. Moreover, IDP-membrane interactions may have a kinetic advantage in fast processes requiring rapid control of such interactions, such as synaptic transmission or signaling. Herein we review the biophysics, regulation and functional implications of IDP-membrane interactions and include a brief overview of some of the methods that can be used to study such interactions. At each step, we use the example of alpha-synuclein, a protein involved in the pathogenesis of Parkinson's disease and one of the best characterized membrane-binding IDP, to illustrate some of the principles discussed.
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Das T, Eliezer D. Probing Structural Changes in Alpha-Synuclein by Nuclear Magnetic Resonance Spectroscopy. Methods Mol Biol 2019; 1948:157-181. [PMID: 30771177 PMCID: PMC8193918 DOI: 10.1007/978-1-4939-9124-2_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Alpha-synuclein, the principal protein involved in the pathogenesis of Parkinson's disease, has been shown to exchange between multiple conformational states, with hitherto unclear physiological role of such conformational changes. Due to its ability to provide rich structural information for proteins in their near-native environment, nuclear magnetic resonance (NMR) spectroscopy has been a valuable tool to study these conformational states. In this review we describe the application of model systems and NMR methods to the study of membrane-bound states of alpha-synuclein. We provide a detailed description, primarily meant for someone new to the field, of how to prepare the necessary samples, perform the basic experiments, and obtain an initial interpretation of the results.
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8
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Exploring the role of methionine residues on the oligomerization and neurotoxic properties of DOPAL-modified α-synuclein. Biochem Biophys Res Commun 2018; 505:295-301. [PMID: 30249394 DOI: 10.1016/j.bbrc.2018.09.111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/17/2018] [Indexed: 11/20/2022]
Abstract
The dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) is believed to play a central role in Parkinson's disease neurodegeneration by stabilizing potentially toxic oligomers of the presynaptic protein α-Synuclein (aSyn). Besides the formation of covalent DOPAL-Lys adducts, DOPAL promotes the oxidation of Met residues of aSyn, which is also a common oxidative post-translational modification found in the protein in vivo. Herein we set out to address the role of Met residues on the oligomerization and neurotoxic properties of DOPAL-modified aSyn. Our data indicate that DOPAL promotes the formation of two distinct types of aSyn oligomers: large and small (dimer and trimers) oligomers, which seem to be generated by independent mechanisms and cannot be interconverted by using denaturing agents. Interestingly, H2O2-treated aSyn monomer, which exhibits all-four Met residues oxidized to Met-sulfoxide, exhibited a reduced ability to form large oligomers upon treatment with DOPAL, with no effect on the population of small oligomers. In this context, triple Met-Val mutant M5V/M116V/M127V exhibited an increased population of large aSyn-DOPAL oligomers in comparison with the wild-type protein. Interestingly, the stabilization of large rather than small oligomers seems to be associated with an enhanced toxicity of DOPAL-aSyn adducts. Collectively, these findings indicate that Met residues may play an important role in modulating both the oligomerization and the neurotoxic properties of DOPAL-derived aSyn species.
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9
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Larsen EK, Olivieri C, Walker C, V S M, Gao J, Bernlohr DA, Tonelli M, Markley JL, Veglia G. Probing Protein-Protein Interactions Using Asymmetric Labeling and Carbonyl-Carbon Selective Heteronuclear NMR Spectroscopy. Molecules 2018; 23:E1937. [PMID: 30081441 PMCID: PMC6205158 DOI: 10.3390/molecules23081937] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 11/23/2022] Open
Abstract
Protein-protein interactions (PPIs) regulate a plethora of cellular processes and NMR spectroscopy has been a leading technique for characterizing them at the atomic resolution. Technically, however, PPIs characterization has been challenging due to multiple samples required to characterize the hot spots at the protein interface. In this paper, we review our recently developed methods that greatly simplify PPI studies, which minimize the number of samples required to fully characterize residues involved in the protein-protein binding interface. This original strategy combines asymmetric labeling of two binding partners and the carbonyl-carbon label selective (CCLS) pulse sequence element implemented into the heteronuclear single quantum correlation (¹H-15N HSQC) spectra. The CCLS scheme removes signals of the J-coupled 15N⁻13C resonances and records simultaneously two individual amide fingerprints for each binding partner. We show the application to the measurements of chemical shift correlations, residual dipolar couplings (RDCs), and paramagnetic relaxation enhancements (PRE). These experiments open an avenue for further modifications of existing experiments facilitating the NMR analysis of PPIs.
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Affiliation(s)
- Erik K Larsen
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Cristina Olivieri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Caitlin Walker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Manu V S
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Jiali Gao
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
| | - David A Bernlohr
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, Madison, WI 53706, USA.
| | - John L Markley
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Gianluigi Veglia
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
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10
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Srb P, Nováček J, Kadeřávek P, Rabatinová A, Krásný L, Žídková J, Bobálová J, Sklenář V, Žídek L. Triple resonance ¹⁵Ν NMR relaxation experiments for studies of intrinsically disordered proteins. JOURNAL OF BIOMOLECULAR NMR 2017; 69:133-146. [PMID: 29071460 DOI: 10.1007/s10858-017-0138-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Description of protein dynamics is known to be essential in understanding their function. Studies based on a well established [Formula: see text] NMR relaxation methodology have been applied to a large number of systems. However, the low dispersion of [Formula: see text] chemical shifts very often observed within intrinsically disordered proteins complicates utilization of standard 2D HN correlated spectra because a limited number of amino acids can be characterized. Here we present a suite of triple resonance HNCO-type NMR experiments for measurements of five [Formula: see text] relaxation parameters ([Formula: see text], [Formula: see text], NOE, cross-correlated relaxation rates [Formula: see text] and [Formula: see text]) in doubly [Formula: see text],[Formula: see text]-labeled proteins. We show that the third spectral dimension combined with non-uniform sampling provides relaxation rates for almost all residues of a protein with extremely poor chemical shift dispersion, the C terminal domain of [Formula: see text]-subunit of RNA polymerase from Bacillus subtilis. Comparison with data obtained using a sample labeled by [Formula: see text] only showed that the presence of [Formula: see text] has a negligible effect on [Formula: see text], [Formula: see text], and on the cross-relaxation rate (calculated from NOE and [Formula: see text]), and that these relaxation rates can be used to calculate accurate spectral density values. Partially [Formula: see text]-labeled sample was used to test if the observed increase of [Formula: see text] [Formula: see text] in the presence of [Formula: see text] corresponds to the [Formula: see text] dipole-dipole interactions in the [Formula: see text],[Formula: see text]-labeled sample.
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Affiliation(s)
- Pavel Srb
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí, 542/2, 166 10, Praha 6, Czech Republic
| | - Jiří Nováček
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Pavel Kadeřávek
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Alžbeta Rabatinová
- Laboratory of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic v.v.i., Videňská 1083, 142 20, Prague, Czech Republic
| | - Libor Krásný
- Laboratory of Molecular Genetics of Bacteria, Institute of Microbiology, Academy of Sciences of the Czech Republic v.v.i., Videňská 1083, 142 20, Prague, Czech Republic
| | - Jitka Žídková
- Institute of Analytical Chemistry of the Czech Academy of Sciences v.v.i., Veveří 97, 602 00, Brno, Czech Republic
| | - Janette Bobálová
- Institute of Analytical Chemistry of the Czech Academy of Sciences v.v.i., Veveří 97, 602 00, Brno, Czech Republic
| | - Vladimír Sklenář
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Lukáš Žídek
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.
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Janowska MK, Baum J. Intermolecular Paramagnetic Relaxation Enhancement (PRE) Studies of Transient Complexes in Intrinsically Disordered Proteins. Methods Mol Biol 2016; 1345:45-53. [PMID: 26453204 DOI: 10.1007/978-1-4939-2978-8_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
NMR interchain paramagnetic relaxation enhancement (PRE) techniques are a very powerful approach for detecting transient interchain interactions between intrinsically disordered proteins. These experiments, requiring a mixed sample containing a 1:1 ratio of isotope-labeled (15)N protein and natural abundance (14)N protein with a paramagnetic spin label, provide data that is limited to interchain interactions only. Application of these experiments to weakly associated transient species such as those that are present in the very early stages of self-assembly processes will aid our understanding of protein aggregation or fibril formation processes.
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Affiliation(s)
- Maria K Janowska
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Jean Baum
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA.
- Center for Integrative Proteomics Research, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ, 08854-8076, USA.
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Matei E, Gronenborn AM. 19
F Paramagnetic Relaxation Enhancement: A Valuable Tool for Distance Measurements in Proteins. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201508464] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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13
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Matei E, Gronenborn AM. (19)F Paramagnetic Relaxation Enhancement: A Valuable Tool for Distance Measurements in Proteins. Angew Chem Int Ed Engl 2015; 55:150-4. [PMID: 26510989 DOI: 10.1002/anie.201508464] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Indexed: 11/11/2022]
Abstract
Fluorine NMR paramagnetic relaxation enhancement was evaluated as a versatile approach for extracting distance information in selectively F-labeled proteins. Proof of concept and initial applications are presented for the HIV-inactivating lectin cyanovirin-N. Single F atoms were introduced at the 4-, 5-, 6- or 7 positions of Trp49 and the 4-position of Phe4, Phe54, and Phe80. The paramagnetic nitroxide spin label was attached to Cys residues that were placed into the protein at positions 50 or 52. (19)F-T2 NMR spectra with different relaxation delays were recorded and the transverse (19)F-PRE rate, (19)F-Γ2 , was used to determine the average distance between the F nucleus and the paramagnetic center. Our data show that experimental (19)F PRE-based distances correspond to 0.93 of the (1)HN-PRE distances, in perfect agreement with the gyromagnetic γ(19)F/γ(1)H ratio, thereby demonstrating that (19)F PREs are excellent alternative parameters for quantitative distance measurements in selectively F-labeled proteins.
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Affiliation(s)
- Elena Matei
- Department of Structural Biology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15260 (USA)
| | - Angela M Gronenborn
- Department of Structural Biology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15260 (USA).
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14
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Follmer C, Coelho-Cerqueira E, Yatabe-Franco DY, Araujo GDT, Pinheiro AS, Domont GB, Eliezer D. Oligomerization and Membrane-binding Properties of Covalent Adducts Formed by the Interaction of α-Synuclein with the Toxic Dopamine Metabolite 3,4-Dihydroxyphenylacetaldehyde (DOPAL). J Biol Chem 2015; 290:27660-79. [PMID: 26381411 DOI: 10.1074/jbc.m115.686584] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Indexed: 01/15/2023] Open
Abstract
Oxidative deamination of dopamine produces the highly toxic aldehyde 3,4-dihydroxyphenylacetaldehyde (DOPAL), enhanced production of which is found in post-mortem brains of Parkinson disease patients. When injected into the substantia nigra of rat brains, DOPAL causes the loss of dopaminergic neurons accompanied by the accumulation of potentially toxic oligomers of the presynaptic protein α-synuclein (aS), potentially explaining the synergistic toxicity described for dopamine metabolism and aS aggregation. In this work, we demonstrate that DOPAL interacts with aS via formation of Schiff-base and Michael-addition adducts with Lys residues, in addition to causing oxidation of Met residues to Met-sulfoxide. DOPAL modification leads to the formation of small aS oligomers that may be cross-linked by DOPAL. Both monomeric and oligomeric DOPAL adducts potently inhibit the formation of mature amyloid fibrils by unmodified aS. The binding of aS to either lipid vesicles or detergent micelles, which results in a gain of α-helix structure in its N-terminal lipid-binding domain, protects the protein against DOPAL adduct formation and, consequently, inhibits DOPAL-induced aS oligomerization. Functionally, aS-DOPAL monomer exhibits a reduced affinity for small unilamellar vesicles with lipid composition similar to synaptic vesicles, in addition to diminished membrane-induced α-helical content in comparison with the unmodified protein. These results suggest that DOPAL could compromise the functionality of aS, even in the absence of protein oligomerization, by affecting the interaction of aS with lipid membranes and hence its role in the regulation of synaptic vesicle traffic in neurons.
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Affiliation(s)
- Cristian Follmer
- From the Departments of Physical Chemistry and the Department of Biochemistry, Weill Cornell Medical College, New York, New York 10065
| | | | | | - Gabriel D T Araujo
- Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro 21941-909, Brazil and
| | - Anderson S Pinheiro
- Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro 21941-909, Brazil and
| | - Gilberto B Domont
- Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro 21941-909, Brazil and
| | - David Eliezer
- the Department of Biochemistry, Weill Cornell Medical College, New York, New York 10065
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15
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Gupta G, Lim L, Song J. NMR and MD Studies Reveal That the Isolated Dengue NS3 Protease Is an Intrinsically Disordered Chymotrypsin Fold Which Absolutely Requests NS2B for Correct Folding and Functional Dynamics. PLoS One 2015; 10:e0134823. [PMID: 26258523 PMCID: PMC4530887 DOI: 10.1371/journal.pone.0134823] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/14/2015] [Indexed: 11/18/2022] Open
Abstract
Dengue genome encodes a two component protease complex (NS2B-NS3pro) essential for the viral maturation/infectivity, thus representing a key drug target. Previously, due to its “complete insolubility”, the isolated NS3pro could not be experimentally studied and it remains elusive what structure it adopts without NS2B and why NS2B is indispensable. Here as facilitated by our previous discovery, the isolated NS3pro has been surprisingly deciphered by NMR to be the first intrinsically-disordered chymotrypsin-like fold, which exists in a loosely-packed state with non-native long-range interactions as revealed by paramagnetic relaxation enhancement (PRE). The disordered NS3pro appears to be needed for binding a human host factor to trigger the membrane remodeling. Moreover, we have in vitro refolded the NS3pro in complex with either NS2B (48–100) or the full-length NS2B (1–130) anchored into the LMPC micelle, and the two complexes have similar activities but different dynamics. We also performed molecular dynamics (MD) simulations and the results revealed that NS2B shows the highest structural fluctuations in the complex, thus providing the dynamic basis for the observation on its conformational exchange between open and closed states. Remarkably, the NS2B cofactor plays a central role in maintaining the correlated motion network required for the catalysis as we previously decoded for the SARS 3CL protease. Indeed, a truncated NS2B (48–100;Δ77–84) with the flexible loop deleted is able to trap the NS2B-NS3pro complex in a highly dynamic and catalytically-impotent state. Taken together, our study implies potential strategies to perturb the NS2B-NS3pro interface for design of inhibitors for treating dengue infection.
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Affiliation(s)
- Garvita Gupta
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore, Singapore
| | - Liangzhong Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore, Singapore
| | - Jianxing Song
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore, Singapore
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16
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Elazari-Shalom H, Shaked H, Esteban-Martin S, Salvatella X, Barda-Saad M, Chill JH. New insights into the role of the disordered WIP N-terminal domain revealed by NMR structural characterization. FEBS J 2015; 282:700-14. [DOI: 10.1111/febs.13174] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 02/06/2023]
Affiliation(s)
| | - Hadassa Shaked
- Department of Chemistry; Bar Ilan University; Ramat Gan Israel
| | - Santiago Esteban-Martin
- Joint BSC-CRG-IRB Research Programme in Computational Biology; Barcelona Supercomputing Center; Spain
| | - Xavier Salvatella
- Joint BSC-CRG-IRB Research Programme in Computational Biology; Institute for Research in Biomedicine IRB Barcelona; Spain
- ICREA; Barcelona Spain
| | - Mira Barda-Saad
- Mina and Everard Goodman Faculty of Life Sciences; Bar Ilan University; Ramat Gan Israel
| | - Jordan H. Chill
- Department of Chemistry; Bar Ilan University; Ramat Gan Israel
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17
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Gu XH, Gong Z, Guo DC, Zhang WP, Tang C. A decadentate Gd(III)-coordinating paramagnetic cosolvent for protein relaxation enhancement measurement. JOURNAL OF BIOMOLECULAR NMR 2014; 58:149-54. [PMID: 24510274 DOI: 10.1007/s10858-014-9817-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/31/2014] [Indexed: 05/26/2023]
Abstract
Solvent paramagnetic relaxation enhancement (sPRE) arises from random collisions between paramagnetic cosolvent and protein of interest. The sPRE can be readily measured, affording protein structure information. However, lack of an inert cosolvent probe may yield sPRE values that are not consistent with protein structure. Here we synthesized a new sPRE probe, triethylenetetraamine hexaacetate trimethylamide gadolinium, or Gd(III)-TTHA-TMA. With a total of 10 coordination sites, this paramagnetic cosovlent eliminates an inner-sphere water molecule that can otherwise transfer relaxation to protein through exchange. With the metal ion centered, the new probe is largely spherical with a radius of 4.0 Å, permitting accurate back calculation of sPRE. The effectiveness Gd(III)-TTHA-TMA as a sPRE probe was demonstrated on three well-studied protein systems.
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Affiliation(s)
- Xin-Hua Gu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics and Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, Hubei Province, China
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