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Makasewicz K, Linse S, Sparr E. Interplay of α-synuclein with Lipid Membranes: Cooperative Adsorption, Membrane Remodeling and Coaggregation. JACS AU 2024; 4:1250-1262. [PMID: 38665673 PMCID: PMC11040681 DOI: 10.1021/jacsau.3c00579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/18/2024] [Accepted: 01/18/2024] [Indexed: 04/28/2024]
Abstract
α-Synuclein is a small neuronal protein enriched at presynaptic termini. It is hypothesized to play a role in neurotransmitter release and synaptic vesicle cycling, while the formation of α-synuclein amyloid fibrils is associated with several neurodegenerative diseases, most notably Parkinson's Disease. The molecular mechanisms of both the physiological and pathological functions of α-synuclein remain to be fully understood, but in both cases, interactions with membranes play an important role. In this Perspective, we discuss several aspects of α-synuclein interactions with lipid membranes including cooperative adsorption, membrane remodeling and α-synuclein amyloid fibril formation in the presence of lipid membranes. We highlight the coupling between the different phenomena and their interplay in the context of physiological and pathological functions of α-synuclein.
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Affiliation(s)
- Katarzyna Makasewicz
- Division
of Physical Chemistry, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | - Sara Linse
- Biochemistry
and Structural Biology, Lund University, SE-22100 Lund, Sweden
| | - Emma Sparr
- Department
of Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
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2
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Wei X, Penkauskas T, Reiner JE, Kennard C, Uline MJ, Wang Q, Li S, Aksimentiev A, Robertson JW, Liu C. Engineering Biological Nanopore Approaches toward Protein Sequencing. ACS NANO 2023; 17:16369-16395. [PMID: 37490313 PMCID: PMC10676712 DOI: 10.1021/acsnano.3c05628] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
Biotechnological innovations have vastly improved the capacity to perform large-scale protein studies, while the methods we have for identifying and quantifying individual proteins are still inadequate to perform protein sequencing at the single-molecule level. Nanopore-inspired systems devoted to understanding how single molecules behave have been extensively developed for applications in genome sequencing. These nanopore systems are emerging as prominent tools for protein identification, detection, and analysis, suggesting realistic prospects for novel protein sequencing. This review summarizes recent advances in biological nanopore sensors toward protein sequencing, from the identification of individual amino acids to the controlled translocation of peptides and proteins, with attention focused on device and algorithm development and the delineation of molecular mechanisms with the aid of simulations. Specifically, the review aims to offer recommendations for the advancement of nanopore-based protein sequencing from an engineering perspective, highlighting the need for collaborative efforts across multiple disciplines. These efforts should include chemical conjugation, protein engineering, molecular simulation, machine-learning-assisted identification, and electronic device fabrication to enable practical implementation in real-world scenarios.
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Affiliation(s)
- Xiaojun Wei
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208, United States
- Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, United States
| | - Tadas Penkauskas
- Biophysics and Biomedical Measurement Group, Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
- School of Engineering, Brown University, Providence, RI 02912, United States
| | - Joseph E. Reiner
- Department of Physics, Virginia Commonwealth University, Richmond, VA 23284, United States
| | - Celeste Kennard
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208, United States
| | - Mark J. Uline
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208, United States
- Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, United States
| | - Qian Wang
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, United States
| | - Sheng Li
- School of Data Science, University of Virginia, Charlottesville, VA 22903, United States
| | - Aleksei Aksimentiev
- Department of Physics and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Joseph W.F. Robertson
- Biophysics and Biomedical Measurement Group, Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Chang Liu
- Biomedical Engineering Program, University of South Carolina, Columbia, SC 29208, United States
- Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, United States
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3
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Ma L, Li X, Petersen RB, Peng A, Huang K. Probing the interactions between amyloidogenic proteins and bio-membranes. Biophys Chem 2023; 296:106984. [PMID: 36889133 DOI: 10.1016/j.bpc.2023.106984] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/11/2023] [Accepted: 02/22/2023] [Indexed: 03/01/2023]
Abstract
Protein misfolding diseases (PMDs) in humans are characterized by the deposition of protein aggregates in tissues, including Alzheimer's disease, Parkinson's disease, type 2 diabetes, and amyotrophic lateral sclerosis. Misfolding and aggregation of amyloidogenic proteins play a central role in the onset and progression of PMDs, and these processes are regulated by multiple factors, especially the interaction between proteins and bio-membranes. Bio-membranes induce conformational changes in amyloidogenic proteins and affect their aggregation; on the other hand, the aggregates of amyloidogenic proteins may cause membrane damage or dysfunction leading to cytotoxicity. In this review, we summarize the factors that affect the binding of amyloidogenic proteins and membranes, the effects of bio-membranes on the aggregation of amyloidogenic proteins, mechanisms of membrane disruption by amyloidogenic aggregates, technical approaches for detecting these interactions, and finally therapeutic strategies targeting membrane damage caused by amyloidogenic proteins.
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Affiliation(s)
- Liang Ma
- Department of Pharmacy, Wuhan Mental Health Center, Wuhan, China; Department of Pharmacy, Wuhan Hospital for Psychotherapy, Wuhan, China
| | - Xi Li
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Robert B Petersen
- Foundational Sciences, Central Michigan University College of Medicine, Mount Pleasant, MI, USA
| | - Anlin Peng
- Department of Pharmacy, The Third Hospital of Wuhan, Tongren Hospital of Wuhan University, Wuhan, China.
| | - Kun Huang
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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4
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Goloborshcheva VV, Kucheryanu VG, Voronina NA, Teterina EV, Ustyugov AA, Morozov SG. Synuclein Proteins in MPTP-Induced Death of Substantia Nigra Pars Compacta Dopaminergic Neurons. Biomedicines 2022; 10:biomedicines10092278. [PMID: 36140378 PMCID: PMC9496024 DOI: 10.3390/biomedicines10092278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/01/2022] [Accepted: 09/06/2022] [Indexed: 11/24/2022] Open
Abstract
Parkinson’s disease (PD) is one of the key neurodegenerative disorders caused by a dopamine deficiency in the striatum due to the death of dopaminergic (DA) neurons of the substantia nigra pars compacta. The initially discovered A53T mutation in the alpha-synuclein gene was linked to the formation of cytotoxic aggregates: Lewy bodies in the DA neurons of PD patients. Further research has contributed to the discovery of beta- and gamma-synucleins, which presumably compensate for the functional loss of either member of the synuclein family. Here, we review research from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity models and various synuclein-knockout animals. We conclude that the differences in the sensitivity of the synuclein-knockout animals compared with the MPTP neurotoxin are due to the ontogenetic selection of early neurons followed by a compensatory effect of beta-synuclein, which optimizes dopamine capture in the synapses. Triple-knockout synuclein studies have confirmed the higher sensitivity of DA neurons to the toxic effects of MPTP. Nonetheless, beta-synuclein could modulate the alpha-synuclein function, preventing its aggregation and loss of function. Overall, the use of knockout animals has helped to solve the riddle of synuclein functions, and these proteins could be promising molecular targets for the development of therapies that are aimed at optimizing the synaptic function of dopaminergic neurons.
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Affiliation(s)
- Valeria V. Goloborshcheva
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
- Correspondence: ; Tel.: +7-(909)-644-92-31
| | | | | | - Ekaterina V. Teterina
- Institute of Physiologically Active Compounds, Russian Academy of Sciences, 142432 Chernogolovka, Russia
| | - Aleksey A. Ustyugov
- Institute of Physiologically Active Compounds, Russian Academy of Sciences, 142432 Chernogolovka, Russia
| | - Sergei G. Morozov
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
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5
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Rajendran M, Queralt-Martín M, Gurnev PA, Rosencrans WM, Rovini A, Jacobs D, Abrantes K, Hoogerheide DP, Bezrukov SM, Rostovtseva TK. Restricting α-synuclein transport into mitochondria by inhibition of α-synuclein-VDAC complexation as a potential therapeutic target for Parkinson's disease treatment. Cell Mol Life Sci 2022; 79:368. [PMID: 35718804 PMCID: PMC11072225 DOI: 10.1007/s00018-022-04389-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/13/2022] [Accepted: 05/20/2022] [Indexed: 11/03/2022]
Abstract
Involvement of alpha-synuclein (αSyn) in Parkinson's disease (PD) is complicated and difficult to trace on cellular and molecular levels. Recently, we established that αSyn can regulate mitochondrial function by voltage-activated complexation with the voltage-dependent anion channel (VDAC) on the mitochondrial outer membrane. When complexed with αSyn, the VDAC pore is partially blocked, reducing the transport of ATP/ADP and other metabolites. Further, αSyn can translocate into the mitochondria through VDAC, where it interferes with mitochondrial respiration. Recruitment of αSyn to the VDAC-containing lipid membrane appears to be a crucial prerequisite for both the blockage and translocation processes. Here we report an inhibitory effect of HK2p, a small membrane-binding peptide from the mitochondria-targeting N-terminus of hexokinase 2, on αSyn membrane binding, and hence on αSyn complex formation with VDAC and translocation through it. In electrophysiology experiments, the addition of HK2p at micromolar concentrations to the same side of the membrane as αSyn results in a dramatic reduction of the frequency of blockage events in a concentration-dependent manner, reporting on complexation inhibition. Using two complementary methods of measuring protein-membrane binding, bilayer overtone analysis and fluorescence correlation spectroscopy, we found that HK2p induces detachment of αSyn from lipid membranes. Experiments with HeLa cells using proximity ligation assay confirmed that HK2p impedes αSyn entry into mitochondria. Our results demonstrate that it is possible to regulate αSyn-VDAC complexation by a rationally designed peptide, thus suggesting new avenues in the search for peptide therapeutics to alleviate αSyn mitochondrial toxicity in PD and other synucleinopathies.
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Affiliation(s)
- Megha Rajendran
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - María Queralt-Martín
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
- Laboratory of Molecular Biophysics, Department of Physics, Universitat Jaume I, Castellón, 12071, Spain
| | - Philip A Gurnev
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - William M Rosencrans
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - Amandine Rovini
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - Daniel Jacobs
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - Kaitlin Abrantes
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - David P Hoogerheide
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Sergey M Bezrukov
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA
| | - Tatiana K Rostovtseva
- Section On Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 9000 Rockville Pike, Bldg. 29B, Room 1G09, Bethesda, MD, 20892, USA.
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6
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Larsen A, John L, Sansom M, Corey R. Specific interactions of peripheral membrane proteins with lipids: what can molecular simulations show us? Biosci Rep 2022; 42:BSR20211406. [PMID: 35297484 PMCID: PMC9008707 DOI: 10.1042/bsr20211406] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 12/04/2022] Open
Abstract
Peripheral membrane proteins (PMPs) can reversibly and specifically bind to biological membranes to carry out functions such as cell signalling, enzymatic activity, or membrane remodelling. Structures of these proteins and of their lipid-binding domains are typically solved in a soluble form, sometimes with a lipid or lipid headgroup at the binding site. To provide a detailed molecular view of PMP interactions with the membrane, computational methods such as molecular dynamics (MD) simulations can be applied. Here, we outline recent attempts to characterise these binding interactions, focusing on both intracellular proteins, such as phosphatidylinositol phosphate (PIP)-binding domains, and extracellular proteins such as glycolipid-binding bacterial exotoxins. We compare methods used to identify and analyse lipid-binding sites from simulation data and highlight recent work characterising the energetics of these interactions using free energy calculations. We describe how improvements in methodologies and computing power will help MD simulations to continue to contribute to this field in the future.
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Affiliation(s)
| | - Laura H. John
- Department of Biochemistry, University of Oxford, Oxford, U.K
| | | | - Robin A. Corey
- Department of Biochemistry, University of Oxford, Oxford, U.K
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7
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Rodrigues-Ferreira C, Lopes JA, Carneiro PF, Dos Santos Lessa C, Galina A, Vieyra A. Bone Marrow Mononuclear Cells Restore Normal Mitochondrial Ca 2+ Handling and Ca 2+-Induced Depolarization of the Internal Mitochondrial Membrane by Inhibiting the Permeability Transition Pore After Ischemia/Reperfusion. Cell Transplant 2022; 31:9636897221085883. [PMID: 35343271 PMCID: PMC8958683 DOI: 10.1177/09636897221085883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Acute kidney injury due to ischemia followed by reperfusion (IR) is a severe clinical condition with high death rates. IR affects the proximal tubule segments due to their predominantly oxidative metabolism and profoundly altered mitochondrial functions. We previously described the impact of IR on oxygen consumption, the generation of membrane potential (ΔΨ), and formation of reactive oxygen species, together with inflammatory and structural alterations. We also demonstrated the benefits of bone marrow mononuclear cells (BMMC) administration in these alterations. The objective of the present study has been to investigate the effect of IR and the influence of BMMC on the mechanisms of Ca2+ handling in mitochondria of the proximal tubule cells. IR inhibited the rapid accumulation of Ca2+ (Ca2+ green fluorescence assays) and induced the opening of the cyclosporine A-sensitive permeability transition pore (PTP), alterations prevented by BMMC. IR accelerated Ca2+-induced decrease of ΔΨ (Safranin O fluorescence assays), as evidenced by decreased requirement for Ca2+ load and t1/2 for complete depolarization. Addition of BMMC and ADP recovered the normal depolarization profile, suggesting that stabilization of the adenine nucleotide translocase (ANT) in a conformation that inhibits PTP opening offers a partial defense mechanism against IR injury. Moreover, as ANT forms a complex with the voltage-dependent anion channel (VDAC) in the outer mitochondrial membrane, it is possible that this complex is also a target for IR injury—thus favoring Ca2+ release, as well as the supramolecular structure that BMMC protects. These beneficial effects are accompanied by a stimulus of the citric acid cycle—which feed the mitochondrial complexes with the electrons removed from different substrates—as the result of accentuated stimulus of citrate synthase activity by BMMC.
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Affiliation(s)
- Clara Rodrigues-Ferreira
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Roberto Alcântara Gomes Institute of Biology, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Jarlene Alécia Lopes
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,National Center for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Priscila Fonseca Carneiro
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cristiane Dos Santos Lessa
- Leopoldo de Meis Institute of Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Antonio Galina
- Leopoldo de Meis Institute of Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adalberto Vieyra
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,National Center for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,National Institute of Science and Technology for Regenerative Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Graduate Program of Translational Biomedicine, Grande Rio University, Duque de Caxias, Brazil
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8
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Hoogerheide DP, Gurnev PA, Rostovtseva TK, Bezrukov SM. Voltage-activated complexation of α-synuclein with three diverse β-barrel channels: VDAC, MspA, and α-hemolysin. Proteomics 2021; 22:e2100060. [PMID: 34813679 DOI: 10.1002/pmic.202100060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 01/07/2023]
Abstract
Voltage-activated complexation is the process by which a transmembrane potential drives complex formation between a membrane-embedded channel and a soluble or membrane-peripheral target protein. Metabolite and calcium flux across the mitochondrial outer membrane was shown to be regulated by voltage-activated complexation of the voltage-dependent anion channel (VDAC) and either dimeric tubulin or α-synuclein (αSyn). However, the roles played by VDAC's characteristic attributes-its anion selectivity and voltage gating behavior-have remained unclear. Here, we compare in vitro measurements of voltage-activated complexation of αSyn with three well-characterized β-barrel channels-VDAC, MspA, and α-hemolysin-that differ widely in their organism of origin, structure, geometry, charge density distribution, and voltage gating behavior. The voltage dependences of the complexation dynamics for the different channels are observed to differ quantitatively but have similar qualitative features. In each case, energy landscape modeling describes the complexation dynamics in a manner consistent with the known properties of the individual channels, while voltage gating does not appear to play a role. The reaction free energy landscapes thus calculated reveal a non-trivial dependence of the αSyn/channel complex stability on the surface density of αSyn.
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Affiliation(s)
- David P Hoogerheide
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Philip A Gurnev
- Section on Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Tatiana K Rostovtseva
- Section on Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Sergey M Bezrukov
- Section on Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
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9
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Rostovtseva TK, Bezrukov SM, Hoogerheide DP. Regulation of Mitochondrial Respiration by VDAC Is Enhanced by Membrane-Bound Inhibitors with Disordered Polyanionic C-Terminal Domains. Int J Mol Sci 2021; 22:7358. [PMID: 34298976 PMCID: PMC8306229 DOI: 10.3390/ijms22147358] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 12/18/2022] Open
Abstract
The voltage-dependent anion channel (VDAC) is the primary regulating pathway of water-soluble metabolites and ions across the mitochondrial outer membrane. When reconstituted into lipid membranes, VDAC responds to sufficiently large transmembrane potentials by transitioning to gated states in which ATP/ADP flux is reduced and calcium flux is increased. Two otherwise unrelated cytosolic proteins, tubulin, and α-synuclein (αSyn), dock with VDAC by a novel mechanism in which the transmembrane potential draws their disordered, polyanionic C-terminal domains into and through the VDAC channel, thus physically blocking the pore. For both tubulin and αSyn, the blocked state is observed at much lower transmembrane potentials than VDAC gated states, such that in the presence of these cytosolic docking proteins, VDAC's sensitivity to transmembrane potential is dramatically increased. Remarkably, the features of the VDAC gated states relevant for bioenergetics-reduced metabolite flux and increased calcium flux-are preserved in the blocked state induced by either docking protein. The ability of tubulin and αSyn to modulate mitochondrial potential and ATP production in vivo is now supported by many studies. The common physical origin of the interactions of both tubulin and αSyn with VDAC leads to a general model of a VDAC inhibitor, facilitates predictions of the effect of post-translational modifications of known inhibitors, and points the way toward the development of novel therapeutics targeting VDAC.
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Affiliation(s)
- Tatiana K. Rostovtseva
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Sergey M. Bezrukov
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
| | - David P. Hoogerheide
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA;
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