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Jing Y, Dogan I, Reetz K, Romanzetti S. Neurochemical changes in the progression of Huntington's disease: A meta-analysis of in vivo 1H-MRS studies. Neurobiol Dis 2024; 199:106574. [PMID: 38914172 DOI: 10.1016/j.nbd.2024.106574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/17/2024] [Accepted: 06/21/2024] [Indexed: 06/26/2024] Open
Abstract
Proton magnetic resonance spectroscopy (1H-MRS) allows measuring specific brain metabolic alterations in Huntington's disease (HD), and these metabolite profiles may serve as non-invasive biomarkers associated with disease progression. Despite this potential, previous findings are inconsistent. Accordingly, we performed a meta-analysis on available in vivo1H-MRS studies in premanifest (Pre-HD) and symptomatic HD stages (Symp-HD), and quantified neurometabolic changes relative to controls in 9 Pre-HD studies (227 controls and 188 mutation carriers) and 14 Symp-HD studies (326 controls and 306 patients). Our results indicated decreased N-acetylaspartate and creatine in the basal ganglia in both Pre-HD and Symp-HD. The overall level of myo-inositol was decreased in Pre-HD while increased in Symp-HD. Besides, Symp-HD patients showed more severe metabolism disruption than Pre-HD patients. Taken together, 1H-MRS is important for elucidating progressive metabolite changes from Pre-HD to clinical conversion; N-acetylaspartate and creatine in the basal ganglia are already sensitive at the preclinical stage and are promising biomarkers for tracking disease progression; overall myo-inositol is a possible characteristic metabolite for distinguishing HD stages.
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Affiliation(s)
- Yinghua Jing
- Department of Neurology, RWTH Aachen University, Aachen, Germany; JARA-Brain Institute Molecular Neuroscience and Neuroimaging (INM-11), Research Centre Jülich and RWTH Aachen University, Aachen, Germany
| | - Imis Dogan
- Department of Neurology, RWTH Aachen University, Aachen, Germany; JARA-Brain Institute Molecular Neuroscience and Neuroimaging (INM-11), Research Centre Jülich and RWTH Aachen University, Aachen, Germany
| | - Kathrin Reetz
- Department of Neurology, RWTH Aachen University, Aachen, Germany; JARA-Brain Institute Molecular Neuroscience and Neuroimaging (INM-11), Research Centre Jülich and RWTH Aachen University, Aachen, Germany
| | - Sandro Romanzetti
- Department of Neurology, RWTH Aachen University, Aachen, Germany; JARA-Brain Institute Molecular Neuroscience and Neuroimaging (INM-11), Research Centre Jülich and RWTH Aachen University, Aachen, Germany.
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2
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Skeens A, Markle JM, Petipas G, Frey SL, Legleiter J. Divalent cations promote huntingtin fibril formation on endoplasmic reticulum derived and model membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184339. [PMID: 38763270 DOI: 10.1016/j.bbamem.2024.184339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 04/24/2024] [Accepted: 05/12/2024] [Indexed: 05/21/2024]
Abstract
Huntington's Disease (HD) is caused by an abnormal expansion of the polyglutamine (polyQ) domain within the first exon of the huntingtin protein (htt). This expansion promotes disease-related htt aggregation into amyloid fibrils and the formation of proteinaceous inclusion bodies within neurons. Fibril formation is a complex heterogenous process involving an array of aggregate species such as oligomers, protofibrils, and fibrils. In HD, structural abnormalities of membranes of several organelles develop. In particular, the accumulation of htt fibrils near the endoplasmic reticulum (ER) impinges upon the membrane, resulting in ER damage, altered dynamics, and leakage of Ca2+. Here, the aggregation of htt at a bilayer interface assembled from ER-derived liposomes was investigated, and fibril formation directly on these membranes was enhanced. Based on these observations, simplified model systems were used to investigate mechanisms associated with htt aggregation on ER membranes. As the ER-derived liposome fractions contained residual Ca2+, the role of divalent cations was also investigated. In the absence of lipids, divalent cations had minimal impact on htt structure and aggregation. However, the presence of Ca2+ or Mg2+ played a key role in promoting fibril formation on lipid membranes despite reduced htt insertion into and association with lipid interfaces, suggesting that the ability of divalent cations to promote fibril formation on membranes is mediated by induced changes to the lipid membrane physicochemical properties. With enhanced concentrations of intracellular calcium being a hallmark of HD, the ability of divalent cations to influence htt aggregation at lipid membranes may play a role in aggregation events that lead to organelle abnormalities associated with disease.
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Affiliation(s)
- Adam Skeens
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, USA
| | - Jordyn M Markle
- The Department of Chemistry, Gettysburg College, 300 N. Washington Street, Gettysburg, PA 17325, USA
| | - Gabriella Petipas
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, USA
| | - Shelli L Frey
- The Department of Chemistry, Gettysburg College, 300 N. Washington Street, Gettysburg, PA 17325, USA.
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, USA; Rockefeller Neurosciences Institutes, West Virginia University, 1 Medical Center Dr., P.O. Box 9303, Morgantown, WV 26505, USA; Department of Neuroscience, West Virginia University, 1 Medical Center Dr., P.O. Box 9303, Morgantown, WV 26505, USA.
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3
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Skeens A, Siriwardhana C, Massinople SE, Wunder MM, Ellis ZL, Keith KM, Girman T, Frey SL, Legleiter J. The polyglutamine domain is the primary driver of seeding in huntingtin aggregation. PLoS One 2024; 19:e0298323. [PMID: 38483973 PMCID: PMC10939245 DOI: 10.1371/journal.pone.0298323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 01/22/2024] [Indexed: 03/17/2024] Open
Abstract
Huntington's Disease (HD) is a fatal, neurodegenerative disease caused by aggregation of the huntingtin protein (htt) with an expanded polyglutamine (polyQ) domain into amyloid fibrils. Htt aggregation is modified by flanking sequences surrounding the polyQ domain as well as the binding of htt to lipid membranes. Upon fibrillization, htt fibrils are able to template the aggregation of monomers into fibrils in a phenomenon known as seeding, and this process appears to play a critical role in cell-to-cell spread of HD. Here, exposure of C. elegans expressing a nonpathogenic N-terminal htt fragment (15-repeat glutamine residues) to preformed htt-exon1 fibrils induced inclusion formation and resulted in decreased viability in a dose dependent manner, demonstrating that seeding can induce toxic aggregation of nonpathogenic forms of htt. To better understand this seeding process, the impact of flanking sequences adjacent to the polyQ stretch, polyQ length, and the presence of model lipid membranes on htt seeding was investigated. Htt seeding readily occurred across polyQ lengths and was independent of flanking sequence, suggesting that the structured polyQ domain within fibrils is the key contributor to the seeding phenomenon. However, the addition of lipid vesicles modified seeding efficiency in a manner suggesting that seeding primarily occurs in bulk solution and not at the membrane interface. In addition, fibrils formed in the presence of lipid membranes displayed similar seeding efficiencies. Collectively, this suggests that the polyQ domain that forms the amyloid fibril core is the main driver of seeding in htt aggregation.
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Affiliation(s)
- Adam Skeens
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Chathuranga Siriwardhana
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Sophia E. Massinople
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Michelle M. Wunder
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Zachary L. Ellis
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Kaitlyn M. Keith
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Tyler Girman
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Shelli L. Frey
- The Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania, United States of America
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
- Rockefeller Neurosciences Institutes, West Virginia University, Morgantown, West Virginia, United States of America
- Department of Neuroscience, West Virginia University, Morgantown, West Virginia, United States of America
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4
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Gamage YI, Pan J. Elucidating the Influence of Lipid Composition on Bilayer Perturbations Induced by the N-terminal Region of the Huntingtin Protein. BIOPHYSICA 2023; 3:582-597. [PMID: 38737720 PMCID: PMC11087071 DOI: 10.3390/biophysica3040040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Understanding the membrane interactions of the N-terminal 17 residues of the huntingtin protein (HttN) is essential for unraveling its role in cellular processes and its impact on huntingtin misfolding. In this study, we used atomic force microscopy (AFM) to examine the effects of lipid specificity in mediating bilayer perturbations induced by HttN. Across various lipid environments, the peptide consistently induced bilayer disruptions in the form of holes. Notably, our results unveiled that cholesterol enhanced bilayer perturbation induced by HttN, while phosphatidylethanolamine (PE) lipids suppressed hole formation. Furthermore, anionic phosphatidylglycerol (PG) and cardiolipin lipids, along with cholesterol at high concentrations, promoted the formation of double-bilayer patches. This unique structure suggests that the synergy among HttN, anionic lipids, and cholesterol can enhance bilayer fusion, potentially by facilitating lipid intermixing between adjacent bilayers. Additionally, our AFM-based force spectroscopy revealed that HttN enhanced the mechanical stability of lipid bilayers, as evidenced by an elevated bilayer puncture force. These findings illuminate the complex interplay between HttN and lipid membranes and provide useful insights into the role of lipid composition in modulating membrane interactions with the huntingtin protein.
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Affiliation(s)
| | - Jianjun Pan
- Department of Physics, University of South Florida, Tampa, FL 33620
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Winkler R, Ciria M, Ahmad M, Plank H, Marcuello C. A Review of the Current State of Magnetic Force Microscopy to Unravel the Magnetic Properties of Nanomaterials Applied in Biological Systems and Future Directions for Quantum Technologies. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2585. [PMID: 37764614 PMCID: PMC10536909 DOI: 10.3390/nano13182585] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/13/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
Magnetism plays a pivotal role in many biological systems. However, the intensity of the magnetic forces exerted between magnetic bodies is usually low, which demands the development of ultra-sensitivity tools for proper sensing. In this framework, magnetic force microscopy (MFM) offers excellent lateral resolution and the possibility of conducting single-molecule studies like other single-probe microscopy (SPM) techniques. This comprehensive review attempts to describe the paramount importance of magnetic forces for biological applications by highlighting MFM's main advantages but also intrinsic limitations. While the working principles are described in depth, the article also focuses on novel micro- and nanofabrication procedures for MFM tips, which enhance the magnetic response signal of tested biomaterials compared to commercial nanoprobes. This work also depicts some relevant examples where MFM can quantitatively assess the magnetic performance of nanomaterials involved in biological systems, including magnetotactic bacteria, cryptochrome flavoproteins, and magnetic nanoparticles that can interact with animal tissues. Additionally, the most promising perspectives in this field are highlighted to make the reader aware of upcoming challenges when aiming toward quantum technologies.
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Affiliation(s)
- Robert Winkler
- Christian Doppler Laboratory—DEFINE, Graz University of Technology, 8010 Graz, Austria; (R.W.); (H.P.)
| | - Miguel Ciria
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain;
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Margaret Ahmad
- Photobiology Research Group, IBPS, UMR8256 CNRS, Sorbonne Université, 75005 Paris, France;
| | - Harald Plank
- Christian Doppler Laboratory—DEFINE, Graz University of Technology, 8010 Graz, Austria; (R.W.); (H.P.)
- Graz Centre for Electron Microscopy, 8010 Graz, Austria
- Institute of Electron Microscopy, Graz University of Technology, 8010 Graz, Austria
| | - Carlos Marcuello
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain;
- Laboratorio de Microscopias Avanzadas (LMA), Universidad de Zaragoza, 50018 Zaragoza, Spain
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6
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Burtscher J, Pepe G, Maharjan N, Riguet N, Di Pardo A, Maglione V, Millet GP. Sphingolipids and impaired hypoxic stress responses in Huntington disease. Prog Lipid Res 2023; 90:101224. [PMID: 36898481 DOI: 10.1016/j.plipres.2023.101224] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/20/2023] [Accepted: 03/05/2023] [Indexed: 03/11/2023]
Abstract
Huntington disease (HD) is a debilitating, currently incurable disease. Protein aggregation and metabolic deficits are pathological hallmarks but their link to neurodegeneration and symptoms remains debated. Here, we summarize alterations in the levels of different sphingolipids in an attempt to characterize sphingolipid patterns specific to HD, an additional molecular hallmark of the disease. Based on the crucial role of sphingolipids in maintaining cellular homeostasis, the dynamic regulation of sphingolipids upon insults and their involvement in cellular stress responses, we hypothesize that maladaptations or blunted adaptations, especially following cellular stress due to reduced oxygen supply (hypoxia) contribute to the development of pathology in HD. We review how sphingolipids shape cellular energy metabolism and control proteostasis and suggest how these functions may fail in HD and in combination with additional insults. Finally, we evaluate the potential of improving cellular resilience in HD by conditioning approaches (improving the efficiency of cellular stress responses) and the role of sphingolipids therein. Sphingolipid metabolism is crucial for cellular homeostasis and for adaptations following cellular stress, including hypoxia. Inadequate cellular management of hypoxic stress likely contributes to HD progression, and sphingolipids are potential mediators. Targeting sphingolipids and the hypoxic stress response are novel treatment strategies for HD.
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Affiliation(s)
- Johannes Burtscher
- Institute of Sport Sciences, University of Lausanne, 1015 Lausanne, Switzerland; Department of Biomedical Sciences, University of Lausanne, 1005 Lausanne, Switzerland.
| | - Giuseppe Pepe
- IRCCS Neuromed, Via Dell'Elettronica, 86077 Pozzilli, Italy
| | - Niran Maharjan
- Department of Neurology, Center for Experimental Neurology, Inselspital University Hospital, 3010 Bern, Switzerland; Department for Biomedical Research (DBMR), University of Bern, 3010 Bern, Switzerland
| | | | - Alba Di Pardo
- IRCCS Neuromed, Via Dell'Elettronica, 86077 Pozzilli, Italy
| | | | - Grégoire P Millet
- Institute of Sport Sciences, University of Lausanne, 1015 Lausanne, Switzerland; Department of Biomedical Sciences, University of Lausanne, 1005 Lausanne, Switzerland
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7
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Beasley M, Frazee N, Groover S, Valentine SJ, Mertz B, Legleiter J. Physicochemical Properties Altered by the Tail Group of Lipid Membranes Influence Huntingtin Aggregation and Lipid Binding. J Phys Chem B 2022; 126:3067-3081. [PMID: 35439000 DOI: 10.1021/acs.jpcb.1c10254] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Huntington's disease is a neurodegenerative disorder caused by an expanded polyglutamine (polyQ) domain within the huntingtin protein (htt) that initiates toxic protein aggregation. Htt directly interacts with membranes, influencing aggregation and spurring membrane abnormalities. These interactions are facilitated by the 17 N-terminal residues (Nt17) that form an amphipathic α-helix implicated in both lipid binding and aggregation. Here, the impact of unsaturation in phospholipid tails on htt-lipid interaction and htt aggregation was determined. There was no correlation between the degree of htt-lipid complexation and the degree of htt aggregation in the presence of each lipid system, indicating that lipid systems with different properties uniquely alter the membrane-mediated aggregation mechanisms. Also, the association between Nt17 and membrane surfaces is determined by complementarity between hydrophobic residues and membrane defects and how easily the peptide can partition into the bilayer. Our results provide critical insights into how membrane physical properties influence downstream htt aggregation.
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Affiliation(s)
- Maryssa Beasley
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States
| | - Nicolas Frazee
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States
| | - Sharon Groover
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States
| | - Stephen J Valentine
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States
| | - Blake Mertz
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States.,WVU Cancer Institute, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, West Virginia 26506, United States.,Blanchette Rockefeller Neurosciences Institutes, West Virginia University, 1 Medical Center Drive, P.O. Box 9303, Morgantown, West Virginia 26505, United States.,Department of Neuroscience, West Virginia University, 1 Medical Center Drive, P.O. Box 9303, Morgantown, West Virginia 26505, United States
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8
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Zou W, Ji D, Zhang Z, Yang L, Cao Y. Players in Mitochondrial Dynamics and Female Reproduction. Front Mol Biosci 2021; 8:717328. [PMID: 34708072 PMCID: PMC8542886 DOI: 10.3389/fmolb.2021.717328] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/07/2021] [Indexed: 01/16/2023] Open
Abstract
Mitochondrial dynamics (fission and fusion) are essential physiological processes for mitochondrial metabolic function, mitochondrial redistribution, and mitochondrial quality control. Various proteins are involved in regulating mitochondrial dynamics. Aberrant expression of these proteins interferes with mitochondrial dynamics and induces a range of diseases. Multiple therapeutic approaches have been developed to treat the related diseases in recent years, but their curative effects are limited. Meanwhile, the role of mitochondrial dynamics in female reproductive function has attracted progressively more attention, including oocyte development and maturation, fertilization, and embryonic development. Here, we reviewed the significance of mitochondrial dynamics, proteins involved in mitochondrial dynamics, and disorders resulting from primary mitochondrial dynamic dysfunction. We summarized the latest therapeutic approaches of hereditary mitochondrial fusion-fission abnormalities and reviewed the recent advances in female reproductive mitochondrial dynamics.
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Affiliation(s)
- Weiwei Zou
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.,NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, China.,Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, Hefei, China
| | - Dongmei Ji
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.,Anhui Province Key Laboratory of Reproductive Health and Genetics, Hefei, China.,Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, China
| | - Zhiguo Zhang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.,Anhui Province Key Laboratory of Reproductive Health and Genetics, Hefei, China.,Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, China
| | - Li Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Yunxia Cao
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.,NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract (Anhui Medical University), Hefei, China.,Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, Hefei, China
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9
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Groover SE, Adegbuyiro A, Fan CK, Hodges BL, Beasley M, Taylor K, Stonebraker AR, Siriwardhana C, Legleiter J. Macromolecular crowding in solution alters huntingtin interaction and aggregation at interfaces. Colloids Surf B Biointerfaces 2021; 206:111969. [PMID: 34246856 DOI: 10.1016/j.colsurfb.2021.111969] [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] [Received: 03/10/2021] [Revised: 06/16/2021] [Accepted: 07/05/2021] [Indexed: 10/20/2022]
Abstract
Huntington's disease (HD) is a fatal neurodegenerative disease caused by an extended polyglutamine (polyQ) domain within the first exon of the huntingtin protein (htt). PolyQ expansion directly invokes the formation of a heterogenous mixture of toxic htt aggregates, including fibrils and oligomers. While htt is a cytosolic protein, it also associates with numerous membranous surfaces within the cell, leading to altered organelle morphology and dysfunction. Here, the impact of macromolecular crowding on htt aggregation in bulk solution and at solid/liquid or membrane/liquid interfaces was investigated. Dextran, Ficoll, and polyethylene glycol (PEG) were used as crowding agents. In bulk solution, crowding enhanced the heterogeneity of non-fibrillar aggregate species formed in a crowder dependent manner. However, crowding agents interfered with the deposition of htt fibrils on mica, suggesting that a crowded aqueous phase influences the interaction of htt with interfaces. By use of in situ atomic force microcopy (AFM), the aggregation of htt directly at mica and bilayer interfaces was tracked. The predominate aggregates type observed to form at the mica interface was fibrillar, but oligomeric aggregates of various stabilities were also observed. Crowding in the aqueous phase suppressed deposition and formation of htt aggregates on mica. In contrast, the addition of crowders enhanced deposition of htt aggregates onto supported total brain lipid extract (TBLE) bilayers. Different crowding agents led to distinct htt aggregates on supported bilayers with unique morphological impact on bilayer integrity. Collectively, these observations point to the complexity of htt aggregation at interfaces and that crowding in the aqueous phase profoundly influences this process.
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Affiliation(s)
- Sharon E Groover
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Adewale Adegbuyiro
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Caleb K Fan
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Breanna L Hodges
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Maryssa Beasley
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Katelyn Taylor
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Alyssa R Stonebraker
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Chathuranga Siriwardhana
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, Morgantown, WV 26506, United States; Rockefeller Neurosciences Institutes, West Virginia University, 1 Medical Center Dr., P.O. Box 9303, Morgantown, WV 26505, United States; Department of Neuroscience, West Virginia University, 1 Medical Center Dr., P.O. Box 9303, Morgantown, WV 26505, United States.
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