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Cario A, Wickramasinghe SP, Rhoades E, Berger CL. The N-terminal disease-associated R5L Tau mutation increases microtubule shrinkage rate due to disruption of microtubule-bound Tau patches. J Biol Chem 2022; 298:102526. [PMID: 36162501 PMCID: PMC9589210 DOI: 10.1016/j.jbc.2022.102526] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 06/28/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 11/25/2022] Open
Abstract
Regulation of the neuronal microtubule cytoskeleton is achieved through the coordination of microtubule-associated proteins (MAPs). MAP-Tau, the most abundant MAP in the axon, functions to modulate motor motility, participate in signaling cascades, as well as directly mediate microtubule dynamics. Tau misregulation is associated with a class of neurodegenerative diseases, known as tauopathies, including progressive supranuclear palsy, Pick's disease, and Alzheimer's disease. Many disease-associated mutations in Tau are found in the C-terminal microtubule-binding domain. These mutations decrease microtubule-binding affinity and are proposed to reduce microtubule stability, leading to disease. N-terminal disease-associated mutations also exist, but the mechanistic details of their downstream effects are not as clear. Here, we investigate the effect of the progressive supranuclear palsy–associated N-terminal R5L mutation on Tau-mediated microtubule dynamics using an in vitro reconstituted system. We show that the R5L mutation does not alter Tau interactions with tubulin by fluorescence correlation spectroscopy. Using total internal reflection fluorescence microscopy, we determined that the R5L mutation has no effect on microtubule growth rate, catastrophe frequency, or rescue frequency. Rather, the R5L mutation increases microtubule shrinkage rate. We determine this is due to disruption of Tau patches, larger order Tau complexes known to form on the GDP-microtubule lattice. Altogether, these results provide insight into the role of Tau patches in mediating microtubule dynamics and suggesting a novel mechanism by which mutations in the N-terminal projection domain reduce microtubule stability.
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Affiliation(s)
- Alisa Cario
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405
| | - Sanjula P Wickramasinghe
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Elizabeth Rhoades
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Christopher L Berger
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405.
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Lo CH, Lim CKW, Ding Z, Wickramasinghe SP, Braun AR, Ashe KH, Rhoades E, Thomas DD, Sachs JN. Targeting the ensemble of heterogeneous tau oligomers in cells: A novel small molecule screening platform for tauopathies. Alzheimers Dement 2019; 15:1489-1502. [PMID: 31653529 DOI: 10.1016/j.jalz.2019.06.4954] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [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: 03/07/2019] [Revised: 05/30/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Understanding the heterogeneous pathology in Alzheimer's disease and related tauopathies is one of the most urgent and fundamental challenges facing the discovery of novel disease-modifying therapies. Through monitoring ensembles of toxic and nontoxic tau oligomers spontaneously formed in cells, our biosensor technology can identify tool compounds that modulate tau oligomer structure and toxicity, providing much needed insight into the nature and properties of toxic tau oligomers. BACKGROUND Tauopathies are a group of neurodegenerative disorders characterized by pathologic aggregation of the microtubule binding protein tau. Recent studies suggest that tau oligomers are the primary toxic species in tauopathies. NEW/UPDATED HYPOTHESIS We hypothesize that tau biosensors capable of monitoring tau oligomer conformation are able to identify tool compounds that modulate the structure and conformation of these tau assemblies, providing key insight into the unique structural fingerprints of toxic tau oligomers. These fingerprints will provide gravely needed biomarker profiles to improve staging of early tauopathy pathology and generate lead compounds for potential new therapeutics. Our time-resolved fluorescence resonance energy transfer biosensors provide us an exquisitely sensitive technique to monitor minute structural changes in monomer and oligomer conformation. In this proof-of-concept study, we identified a novel tool compound, MK-886, which directly binds tau, perturbs the conformation of toxic tau oligomers, and rescues tau-induced cytotoxicity. Furthermore, we show that MK-886 alters the conformation of tau monomer at the proline-rich and microtubule binding regions, stabilizing an on-pathway oligomer. MAJOR CHALLENGES FOR THE HYPOTHESIS Our approach monitors changes in the ensemble of assemblies that are spontaneously formed in cells but does not specifically isolate or enrich unique toxic tau species. However, time-resolved fluorescence resonance energy transfer does not provide high-resolution, atomic scale information, requiring additional experimental techniques to resolve the structural features stabilized by different tool compounds. LINKAGE TO OTHER MAJOR THEORIES Our biosensor technology is broadly applicable to other areas of tauopathy therapeutic development. These biosensors can be readily modified for different isoforms of tau, specific post-translational modifications, and familial Alzheimer's disease-associated mutations. We are eager to explore tau interactions with chaperone proteins, monitor cross-reactivity with other intrinsically disordered proteins, and target seeded oligomer pathology.
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Affiliation(s)
- Chih Hung Lo
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Colin Kin-Wye Lim
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Zhipeng Ding
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Sanjula P Wickramasinghe
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
| | - Anthony R Braun
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Karen H Ashe
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA; N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, USA; Geriatric Research, Education, and Clinical Centers, Veterans Affairs Medical Center, Minneapolis, MN, USA
| | - Elizabeth Rhoades
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA, USA; Department of Chemistry, University of Pennsylvania, Philadelphia, PA, USA
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA; Photonic Pharma LLC, Minneapolis, MN, USA
| | - Jonathan N Sachs
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA.
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Usery RD, Enoki TA, Wickramasinghe SP, Nguyen VP, Ackerman DG, Greathouse DV, Koeppe RE, Barrera FN, Feigenson GW. Membrane Bending Moduli of Coexisting Liquid Phases Containing Transmembrane Peptide. Biophys J 2019; 114:2152-2164. [PMID: 29742408 DOI: 10.1016/j.bpj.2018.03.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/19/2018] [Accepted: 03/22/2018] [Indexed: 11/25/2022] Open
Abstract
A number of highly curved membranes in vivo, such as epithelial cell microvilli, have the relatively high sphingolipid content associated with "raft-like" composition. Given the much lower bending energy measured for bilayers with "nonraft" low sphingomyelin and low cholesterol content, observing high curvature for presumably more rigid compositions seems counterintuitive. To understand this behavior, we measured membrane rigidity by fluctuation analysis of giant unilamellar vesicles. We found that including a transmembrane helical GWALP peptide increases the membrane bending modulus of the liquid-disordered (Ld) phase. We observed this increase at both low-cholesterol fraction and higher, more physiological cholesterol fraction. We find that simplified, commonly used Ld and liquid-ordered (Lo) phases are not representative of those that coexist. When Ld and Lo phases coexist, GWALP peptide favors the Ld phase with a partition coefficient of 3-10 depending on mixture composition. In model membranes at high cholesterol fractions, Ld phases with GWALP have greater bending moduli than the Lo phase that would coexist.
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Affiliation(s)
- Rebecca D Usery
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York
| | - Thais A Enoki
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York
| | - Sanjula P Wickramasinghe
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Vanessa P Nguyen
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee
| | - David G Ackerman
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Scientific Computing, Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia
| | - Denise V Greathouse
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas
| | - Roger E Koeppe
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas
| | - Francisco N Barrera
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee
| | - Gerald W Feigenson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York.
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Usery RD, Enoki TA, Wickramasinghe SP, Nguyen VP, Ackerman DG, Greathouse DV, Koeppe RE, Barrera FN, Feigenson GW. Membrane Bending Moduli of Coexisting Liquid Phases Containing Transmembrane Peptide. Biophys J 2018; 115:164. [PMID: 29972808 DOI: 10.1016/j.bpj.2018.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Usery RD, Enoki TA, Wickramasinghe SP, Weiner MD, Tsai WC, Kim MB, Wang S, Torng TL, Ackerman DG, Heberle FA, Katsaras J, Feigenson GW. Line Tension Controls Liquid-Disordered + Liquid-Ordered Domain Size Transition in Lipid Bilayers. Biophys J 2017; 112:1431-1443. [PMID: 28402885 DOI: 10.1016/j.bpj.2017.02.033] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/27/2017] [Accepted: 02/16/2017] [Indexed: 12/28/2022] Open
Abstract
To better understand animal cell plasma membranes, we studied simplified models, namely four-component lipid bilayer mixtures. Here we describe the domain size transition in the region of coexisting liquid-disordered (Ld) + liquid-ordered (Lo) phases. This transition occurs abruptly in composition space with domains increasing in size by two orders of magnitude, from tens of nanometers to microns. We measured the line tension between coexisting Ld and Lo domains close to the domain size transition for a variety of lipid mixtures, finding that in every case the transition occurs at a line tension of ∼0.3 pN. A computational model incorporating line tension and dipole repulsion indicated that even small changes in line tension can result in domains growing in size by several orders of magnitude, consistent with experimental observations. We find that other properties of the coexisting Ld and Lo phases do not change significantly in the vicinity of the abrupt domain size transition.
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Affiliation(s)
- Rebecca D Usery
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York
| | - Thais A Enoki
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York
| | - Sanjula P Wickramasinghe
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Department of Biochemistry and Biophysics at the University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Wen-Chyan Tsai
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York
| | - Mary B Kim
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Department of Medicine, Baylor College of Medicine, Houston, Texas
| | - Shu Wang
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Harvard Medical School Library of Integrated Network-based Cellular Signatures Center and Laboratory of Systems Pharmacology, Harvard University, Boston, Massachusetts
| | - Thomas L Torng
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Department of Biochemistry, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire
| | - David G Ackerman
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York; Scientific Computing, Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia
| | - Frederick A Heberle
- Joint Institute for Biological Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee; Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee; The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Tennessee
| | - John Katsaras
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee; Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee
| | - Gerald W Feigenson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York.
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Wickramasinghe SP, Ackerman DG, Feigenson GW. Appearance of Modulated Bilayer Morphology for Coexisting LD and LO Phases is Correlated with Line Tension. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.1335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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