Article
Biochemistry & Molecular Biology
Hamza Arshad, Zeel Patel, Genki Amano, Le yao Li, Zaid A. M. Al-Azzawi, Surachai Supattapone, Gerold Schmitt-Ulms, Joel C. Watts
Summary: The bank vole prion protein can act as a universal acceptor of prions from different species. Through a cell culture paradigm, it has been found that bank vole prion protein can facilitate cross-species prion replication, and a single amino acid change can alter its permissiveness to prions. This cellular model will be valuable for studying the molecular features of bank vole prion protein as a universal prion acceptor.
JOURNAL OF NEUROCHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Maximo Sanz-Hernandez, Joseph D. Barritt, Jens Sobek, Simone Hornemann, Adriano Aguzzi, Alfonso De Simone
Summary: The T183A variant of human PrP significantly enhances aggregation propensity, leading to amyloid formation under physiological conditions by the sole C-terminal domain of the protein. The study identified the structural characteristics of the misfolded intermediate promoting aggregation of T183A huPrP and the interactions preventing the population of this species in the wild-type protein, supporting the use of POM antibodies to suppress the aggregation of this amyloidogenic mutant.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Neurosciences
Eiko N. Minakawa, Yoshitaka Nagai
Summary: Polyglutamine diseases are a group of inherited neurodegenerative disorders caused by abnormal expansion of CAG trinucleotide repeats. Stabilizing protein conformation and inhibiting aggregation offer promising therapeutic approaches, while gene silencing to reduce expression of expanded polyQ proteins is another potential treatment avenue. These advancements hold promise for delaying or preventing the progression of currently incurable diseases.
FRONTIERS IN NEUROSCIENCE
(2021)
Review
Cell Biology
Barbara Tedesco, Leen Vendredy, Vincent Timmerman, Angelo Poletti
Summary: Each protein must be correctly synthesized, folded, and transported to its appropriate location. Failure in these steps can lead to protein misfolding and potential damage. Cells have well-characterized protein quality control systems, including autophagy and chaperone-assisted selective autophagy (CASA), to minimize such issues. The CASA complex, composed of HSPA, HSPB8, and BAG3 proteins, is essential for maintaining protein homeostasis and mutations in these genes can result in (cardio)myopathies and neurodegenerative diseases. This article summarizes the current understanding of the CASA complex and discusses its involvement in diseases and potential therapeutic targets.
Editorial Material
Microbiology
Charlotte I. Z. O'Hern, Karrera Y. Djoko
Summary: Recent research has shown that copper is both an essential micronutrient and cytotoxic to cells. The study found that cells accumulate more copper under anoxic conditions, making copper more cytotoxic in anoxic environments. The study further revealed that copper cytotoxicity in anoxic bacteria is associated with increased intracellular protein aggregation. Understanding the speciation and availability of copper in cells is crucial for uncovering the cellular consequences of copper cytotoxicity.
Review
Geriatrics & Gerontology
Rodrigo Diaz-Espinoza
Summary: Amyloids are highly ordered aggregates composed of proteins or peptides involved in various pathologies, including Alzheimer's and Parkinson's diseases. The specific features of these amyloid structures, such as the Greek-key topology and two-fold symmetry, can serve as novel guides for seeking potential molecular targets in drug design efforts. Advances in solid state NMR and Cryogenic-electron microscopy have allowed the elucidation of these elusive conformations at high resolution.
FRONTIERS IN AGING NEUROSCIENCE
(2021)
Review
Neurosciences
Sean L. Johnson, Wei-Ling Tsou, Matthew V. Prifti, Autumn L. Harris, Sokol V. Todi
Summary: The presence and aggregation of misfolded proteins have harmful effects on the nervous system, specifically in the family of polyglutamine (polyQ) disorders. These disorders are caused by the abnormal elongation of a polyQ repeat in different proteins, leading to misfolding, aggregation, cellular dysfunction, and diseases. However, each disease is distinct due to the surrounding regions, interacting proteins, and posttranslational modifications. This overview focuses on the control of pathogenicity in the expanded polyQ repeat by non-polyQ regions and explores shared processes and therapeutic entry points for these incurable disorders.
FRONTIERS IN MOLECULAR NEUROSCIENCE
(2022)
Article
Biology
Juan R. Coca, Hasier Erana, Joaquin Castilla
Summary: This study delves into the molecular pathways of PrPC and PrPSc proteins, investigating the code of meanings at the molecular level in relation to prion diseases. It also explores potential relationships between prion proteins and other proteins to uncover the semiotic expansion of the PrP code. By analyzing these connections, the study aims to further understand the unusual pathological processes described by Nobel laureate Prusiner.
Article
Biochemistry & Molecular Biology
Giulia Fani, Benedetta Mannini, Giulia Vecchi, Roberta Cascella, Cristina Cecchi, Christopher M. Dobson, Michele Vendruscolo, Fabrizio Chiti
Summary: Alzheimer's disease, the most common form of dementia, is characterized by the toxicity mechanism of Aβ oligomers through perturbing the mechanical properties of lipid membranes sensed by NMDA and AMPA receptors.
ACS CHEMICAL NEUROSCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Giulia Fani, Chiara Ester La Torre, Roberta Cascella, Cristina Cecchi, Michele Vendruscolo, Fabrizio Chiti
Summary: Alzheimer's disease is characterized by the accumulation of amyloid beta (A beta) peptide in the brain, which leads to the formation of senile plaques. The aggregation process of A beta also generates smaller misfolded oligomers that contribute to disease progression. These oligomers interact with cell membranes, increasing intracellular Ca2+ levels and producing reactive oxygen species (ROS). Our study found that the increase in intracellular Ca2+ occurs faster than the increase in ROS levels after exposure to misfolded protein oligomers. Removing Ca2+ from the cell medium prevents the increase in intracellular Ca2+ and abolishes ROS production. Treating cells with antioxidant agents prevents ROS formation, but does not prevent the initial increase in Ca2+, allowing the cells to restore normal calcium levels. These findings suggest that Ca2+ influx triggers ROS production in cells challenged by aberrant protein oligomers.
CELLULAR AND MOLECULAR LIFE SCIENCES
(2022)
Review
Biochemistry & Molecular Biology
Diane L. Ritchie, Marcelo A. Barria
Summary: Accumulation and propagation of misfolded proteins in the brain are shared pathological features of many neurodegenerative diseases. While there is no epidemiological evidence suggesting infectiousness in neurodegenerative disorders, experimental models show potential prion-like transmission of other pathogenic proteins. Concerns exist regarding the transmission of misfolded proteins beyond prion protein.
Review
Chemistry, Multidisciplinary
Yoshiaki Furukawa
Summary: This review discusses the importance of metal binding and disulfide formation in Cu/Zn-superoxide dismutase (SOD1) for stabilizing protein structure and enzymatic function, as well as the potential link between failure of these processes and neurodegenerative diseases caused by protein misfolding.
Article
Biochemistry & Molecular Biology
Minoo Qafary, Khosro Khajeh, Matteo Ramazzotti, Ali Akbar Moosavi-Movahedi, Fabrizio Chiti
Summary: A novel lipase from Pseudomonas sp. with high aggregation propensity was studied to elucidate its physicochemical and structural determinants. Amyloid-like structures were found to form at high concentrations, while stable structures were observed in the absence of typical sequence characteristics.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Review
Biochemistry & Molecular Biology
Songzhe He, Fushun Wang, Ken Kin Lam Yung, Shiqing Zhang, Shaogang Qu
Summary: This review summarizes the structure, physiological function, and effects of post-translational modifications on alpha-syn aggregation, which may elucidate mechanisms for Parkinson's disease pathogenesis and lay a theoretical foundation for clinical treatment.
ACS CHEMICAL NEUROSCIENCE
(2021)
Review
Pharmacology & Pharmacy
Feng Chen, Huiyi Chen, Yanting Chen, Wenyan Wei, Yuanhong Sun, Lu Zhang, Lili Cui, Yan Wang
Summary: Communication between neurons relies on synaptic vesicle exocytosis, a process facilitated by the SNARE complex. Dysfunction of the SNARE complex in synapses may contribute to abnormal neurotransmission and lead to synaptic dysfunction. Research suggests that the SNARE complex could be a significant molecular target in neurological diseases.
PHARMACOLOGICAL RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Chuanxu Ma, Zhongcan Xiao, Alexander A. Puretzky, Hao Wang, Ali Mohsin, Jingsong Huang, Liangbo Liang, Yingdong Luo, Benjamin J. Lawrie, Gong Gu, Wenchang Lu, Kunlun Hong, Jerzy Bernholc, An-Ping Li
Article
Chemistry, Physical
Yang Liu, Bing Zhang, Wenhan Xu, Aziguli Haibibu, Zhubing Han, Wenchang Lu, J. Bernholc, Qing Wang
Article
Chemistry, Physical
Chenyi Zhou, Wenhan Xu, Bing Zhang, Yunhe Zhang, Chen Shen, Qinfei Xu, Xin Liu, Florian Bertram, Jerzy Bernholc, Zhenhua Jiang, Yingshuang Shang, Haibo Zhang
Summary: Researchers have demonstrated a polymer with high energy density discharge performance, which can achieve excellent capacitance performance at higher temperatures. The unique structure of this polymer, characterized by curled and densely packed chains, can be produced using existing industrial processes and is suitable for large-scale applications.
CHEMISTRY OF MATERIALS
(2022)
Article
Multidisciplinary Sciences
Xiaoshi Qian, Donglin Han, Lirong Zheng, Jie Chen, Madhusudan Tyagi, Qiang Li, Feihong Du, Shanyu Zheng, Xingyi Huang, Shihai Zhang, Junye Shi, Houbing Huang, Xiaoming Shi, Jiangping Chen, Hancheng Qin, Jerzy Bernholc, Xin Chen, Long-Qing Chen, Liang Hong, Q. M. Zhang
Summary: A new class of EC polymer has been developed, showing significantly enhanced performance under lower electric fields compared to state-of-the-art materials. This improvement is achieved by increasing the number of polar entities in the polymer through the conversion of a small number of chlorofluoroethylene groups into covalent double bonds. The polymer displays high-entropy polar phases with low energy barrier for electric-field-induced switching, maintaining performance for over one million cycles at low fields suitable for practical EC cooling applications.
Article
Physics, Applied
Hancheng Qin, Wenchang Lu, J. Bernholc
Summary: The precise atomic structure of metal contacts plays a significant role in the performance of nanoscale electronic devices. Researchers used a DFT-based method to evaluate different metal contacts with graphene or graphene nanoribbons, finding that surface metal contacts unbound to graphene had lower resistance with titanium (Ti) contacts compared to gold (Au), calcium (Ca), iridium (Ir), platinum (Pt), and strontium (Sr). However, as an edge contact, titanium had higher resistance than gold. Additionally, bridging oxygen atoms at the titanium and gold edge contacts reduced transmission by over 30%.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Xin Chen, Hancheng Qin, Xiaoshi Qian, Wenyi Zhu, Bo Li, Bing Zhang, Wenchang Lu, Ruipeng Li, Shihai Zhang, Lei Zhu, Fabrice Domingues Dos Santos, J. Bernholc, Q. M. Zhang
Summary: Introducing a small amount of fluorinated alkyne monomers enhances the polarization change in ferroelectric polymers, leading to a strong electromechanical coupling effect.
Article
Polymer Science
Xin Chen, Hancheng Qin, Wenyi Zhu, Bing Zhang, Wenchang Lu, J. Bernholc, Q. M. Zhang
Summary: Recently, it was discovered that converting chlorofluoroethylene (CFE) into fluorinated alkyne (FA) in P(VDF-TrFE-CFE) polymeric materials can result in P(VDF-TrFE-CFE-FA) tetrapolymers with exceptional electromechanical response at ultralow electric fields. This effect is attributed to the conversion of bulky CFE into small-size FA defects, which weakens the relaxor behavior and allows for a diffused critical endpoint transition region. The near 2 mol % FA content in the tetrapolymers enables a small change in the electric field to induce a large electroactuation, presenting new opportunities for novel applications.
Article
Physics, Applied
Xin Chen, Hancheng Qin, Yang Liu, Yen-Ting Lin, Bing Zhang, Wenchang Lu, Seong H. H. Kim, J. Bernholc, Qing Wang, Q. M. Zhang
Summary: The origin of dielectric constant enhancement in high-temperature polymer dilute nanocomposites is investigated. Trace nanofiller loadings can greatly enhance the dielectric constant without affecting breakdown strength and dielectric loss. The interface regions between the polymers and trace nanofillers play a crucial role in the observed enhancement.
APPLIED PHYSICS LETTERS
(2023)
Article
Polymer Science
Zhubing Han, Hancheng Qin, Xin Chen, Wenhan Xu, Yang Liu, J. Bernholc, Qing Wang
Summary: The incorporation of comonomers in PVDF-based ferroelectric polymers has been widely used to modify their structures and properties. Previous studies have shown that large-sized comonomers can induce relaxor ferroelectricity, but this study demonstrates that a small-sized comonomer can preferentially adopt a polar all-trans conformation, resulting in terpolymers with robust ferroelectricity and enhanced transition temperature and coercive field. This work systematically investigates the effects of comonomer size on the microstructures and properties of ferroelectric polymers.
Article
Chemistry, Physical
Yang Liu, Yao Zhou, Hancheng Qin, Tiannan Yang, Xin Chen, Li Li, Zhubing Han, Ke Wang, Bing Zhang, Wenchang Lu, Long-Qing Chen, J. Bernholc, Qing Wang
Summary: This article introduces a composite material of poly(vinylidene fluoride) and TiO2, which exhibits superior performance in terms of piezoelectric activity and mechanical energy density driven by Joule heating. The interconversion between electrical and mechanical energies is crucial for ferroelectric materials to be used in transducers, actuators, and sensors. The composite material demonstrates a strain over 8% and an output mechanical energy density of 11.3 J cm(-3) at an electric field of 40 MV m(-1), outperforming conventional ferroelectric ceramics and crystals.
Article
Materials Science, Multidisciplinary
Felix Lupke, Anh D. Pham, Yi-Fan Zhao, Ling-Jie Zhou, Wenchang Lu, Emil Briggs, Jerzy Bernholc, Marek Kolmer, Jacob Teeter, Wonhee Ko, Cui-Zu Chang, Panchapakesan Ganesh, An-Ping Li
Summary: The study investigates the local signatures of thickness-dependent topology in MnBi2Te4 thin films using scanning tunneling microscopy and spectroscopy. Theoretical calculations reveal a topological quantum phase transition beyond a film thickness of one monolayer, with alternating quantum anomalous Hall effect and axion insulating states, and localized electronic states at step edges.
Article
Chemistry, Multidisciplinary
Chuanxu Ma, Zhongcan Xiao, Peter Bonnesen, Liangbo Liang, Alexander A. Puretzky, Jingsong Huang, Marek Kolmer, Bobby G. Sumpter, Wenchang Lu, Kunlun Hong, Jerzy Bernholc, An-Ping Li
Summary: This study investigates the cyclodehydrogenation reaction mechanism in the on-surface synthesis of graphene nanoribbons using isotopic labeling. A reaction pathway involving conrotatory electrocyclization and a [1,9]-sigmatropic D shift, followed by H/D eliminations, is identified and substantiated by experiments and simulations. The research not only helps clarify the reaction process in GNR synthesis, but also presents a rational strategy for designing precise hydrogen/deuterium isotope labeling patterns in on-surface reactions.
Article
Materials Science, Multidisciplinary
Qiyan Zhang, Xin Chen, Bing Zhang, Tian Zhang, Wengchang Lu, Zhe Chen, Ziyu Liu, Seong H. Kim, Brian Donovan, Ronald J. Warzoha, Enrique D. Gomez, J. Bernholc, Q. M. Zhang
Summary: This research demonstrates a strategy to reduce weak points in polymers by utilizing interchain electrostatic forces in polymer blends, leading to significant enhancements in dielectric breakdown strength.
Article
Chemistry, Multidisciplinary
Bing Zhang, Xin Chen, Wenchang Lu, Q. M. Zhang, J. Bernholc
Summary: The weakening of hydrogen bonds between nanoparticles and polymer chains reduces the dielectric enhancement in the composite material. Multiscale simulations showed that the attachment of solvated highly dipolar polymers to oxide nanoparticles results in deposition of nanoparticle-polymer blobs during solution casting. The increased free volume in the nanocomposite enables easier reorientation of monomer dipoles with an applied electric field, leading to a higher dielectric permittivity.
Article
Chemistry, Inorganic & Nuclear
Jiayong Zhang, Yongqiang Cheng, Alexander I. Kolesnikov, Jerry Bernholc, Wenchang Lu, Anibal J. Ramirez-Cuesta
Summary: The anharmonic phonon behavior in zirconium hydrides and deuterides has been investigated using inelastic neutron scattering and lattice dynamics calculations within the framework of density functional theory. The study found that anharmonicity in these materials originates from deviations of hydrogen potentials from quadratic behavior in certain directions and is apparent for higher-order excited vibrational states. Convolution of the eigenfrequencies with the instrument resolution qualitatively describes the anharmonic peaks in the experimental data.