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Kryvokhyzha M, Litvinov S, Danchenko M, Khudolieieva L, Kutsokon N, Baráth P, Rashydov N. How does ionizing radiation affect amyloidogenesis in plants? Int J Radiat Biol 2024:1-12. [PMID: 38530837 DOI: 10.1080/09553002.2024.2331126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/27/2023] [Accepted: 03/07/2024] [Indexed: 03/28/2024]
Abstract
PURPOSE Ionizing radiation is a harsh environmental factor that could induce plant senescence. We hypothesized that radiation-related senescence remodels proteome, particularly by triggering the accumulation of prion-like proteins in plant tissues. The object of this study, pea (Pisum sativum L.), is an agriculturally important legume. Research on the functional importance of amyloidogenic proteins was never performed on this species. MATERIALS AND METHODS Pea seeds were irradiated in the dose range 5-50 Gy of X-rays. Afterward, Fourier-transform infrared spectroscopy (FTIR) was used to investigate changes in the secondary structure of proteins in germinated 3-day-old seedlings. Specifically, we evaluated the ratio between the amide I and II peaks. Next, we performed protein staining with Congo red to compare the presence of amyloids in the samples. In parallel, we profiled the detergent-resistant proteome fraction by ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS). Differentially accumulated proteins were functionally analyzed in MapMan software, and the PLAAC tool was used to predict putative prion-like proteins. RESULTS We showed a reduced germination rate but higher plant height and faster appearance of reproductive organs in the irradiated at dose of 50 Gy group compared with the control; furthermore, we demonstrated more β-sheets and amyloid aggregates in the roots of stressed plants. We detected 531 proteins in detergent-resistant fraction extracted from roots, and 45 were annotated as putative prion-like proteins. Notably, 29 proteins were significantly differentially abundant between the irradiated and the control groups. These proteins belong to several functional categories: amino acid metabolism, carbohydrate metabolism, cytoskeleton organization, regulatory processes, protein biosynthesis, and RNA processing. Thus, the discovery proteomics provided deep data on novel aspects of plant stress biology. CONCLUSION Our data hinted that protein accumulation stimulated seedlings' growth as well as accelerated ontogenesis and, eventually, senescence, primarily through translation and RNA processing. The increased abundance of primary metabolism-related proteins indicates more intensive metabolic processes triggered in germinating pea seeds upon X-ray exposure. The functional role of detected putative amyloidogenic proteins should be validated in overexpression or knockout follow-up studies.
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Affiliation(s)
- Maryna Kryvokhyzha
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, Kyiv, Ukraine
- Institute of Plant Genetics and Biotechnology, Plant Science and Biodiversity Center, Slovak Academy of Sciences, Nitra, Slovakia
| | - Sergii Litvinov
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Maksym Danchenko
- Institute of Plant Genetics and Biotechnology, Plant Science and Biodiversity Center, Slovak Academy of Sciences, Nitra, Slovakia
| | - Lidiia Khudolieieva
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Nataliia Kutsokon
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Peter Baráth
- Department of Glycobiology, Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Namik Rashydov
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, Kyiv, Ukraine
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Nesterov SV, Plokhikh KS, Chesnokov YM, Mustafin DA, Goleva TN, Rogov AG, Vasilov RG, Yaguzhinsky LS. Safari with an Electron Gun: Visualization of Protein and Membrane Interactions in Mitochondria in Natural Environment. Biochemistry (Mosc) 2024; 89:257-268. [PMID: 38622094 DOI: 10.1134/s0006297924020068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 02/06/2024] [Accepted: 02/07/2024] [Indexed: 04/17/2024]
Abstract
This paper presents new structural data about mitochondria using correlative light and electron microscopy (CLEM) and cryo-electron tomography. These state-of-the-art structural biology methods allow studying biological objects at nanometer scales under natural conditions. Non-invasiveness of these methods makes them comparable to observing animals in their natural environment on a safari. The paper highlights two areas of research that can only be accomplished using these methods. The study visualized location of the Aβ42 amyloid aggregates in relation to mitochondria to test a hypothesis of development of mitochondrial dysfunction in Alzheimer's disease. The results showed that the Aβ42 aggregates do not interact with mitochondria, although some of them are closely located. Therefore, the study demonstrated that mitochondrial dysfunction is not directly associated with the effects of aggregates on mitochondrial structure. Other processes should be considered as sources of mitochondrial dysfunction. Second unique area presented in this work is high-resolution visualization of the mitochondrial membranes and proteins in them. Analysis of the cryo-ET data reveals toroidal holes in the lamellar structures of cardiac mitochondrial cristae, where ATP synthases are located. The study proposes a new mechanism for sorting and clustering protein complexes in the membrane based on topology. According to this suggestion, position of the OXPHOS system proteins in the membrane is determined by its curvature. High-resolution tomography expands and complements existing ideas about the structural and functional organization of mitochondria. This makes it possible to study the previously inaccessible structural interactions of proteins with each other and with membranes in vivo.
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Affiliation(s)
- Semen V Nesterov
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
| | | | - Yuriy M Chesnokov
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Denis A Mustafin
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Tatyana N Goleva
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Anton G Rogov
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Raif G Vasilov
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Lev S Yaguzhinsky
- Belozersky Research Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119992, Russia
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Vendruscolo M. Thermodynamic and kinetic approaches for drug discovery to target protein misfolding and aggregation. Expert Opin Drug Discov 2023:1-11. [PMID: 37276120 DOI: 10.1080/17460441.2023.2221024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 01/23/2023] [Accepted: 05/30/2023] [Indexed: 06/07/2023]
Abstract
INTRODUCTION Protein misfolding diseases, including Alzheimer's and Parkinson's diseases, are characterized by the aberrant aggregation of proteins. These conditions are still largely untreatable, despite having a major impact on our healthcare systems and societies. AREAS COVERED We describe drug discovery strategies to target protein misfolding and aggregation. We compare thermodynamic approaches, which are based on the stabilization of the native states of proteins, with kinetic approaches, which are based on the slowing down of the aggregation process. This comparison is carried out in terms of the current knowledge of the process of protein misfolding and aggregation, the mechanisms of disease and the therapeutic targets. EXPERT OPINION There is an unmet need for disease-modifying treatments that target protein misfolding and aggregation for the over 50 human disorders known to be associated with this phenomenon. With the approval of the first drugs that can prevent misfolding or inhibit aggregation, future efforts will be focused on the discovery of effective compounds with these mechanisms of action for a wide range of conditions.
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Affiliation(s)
- Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
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Mullick P, Trovato A. Sequence-Based Prediction of Protein Phase Separation: The Role of Beta-Pairing Propensity. Biomolecules 2022; 12. [PMID: 36551199 DOI: 10.3390/biom12121771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/10/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
The formation of droplets of bio-molecular condensates through liquid-liquid phase separation (LLPS) of their component proteins is a key factor in the maintenance of cellular homeostasis. Different protein properties were shown to be important in LLPS onset, making it possible to develop predictors, which try to discriminate a positive set of proteins involved in LLPS against a negative set of proteins not involved in LLPS. On the other hand, the redundancy and multivalency of the interactions driving LLPS led to the suggestion that the large conformational entropy associated with non specific side-chain interactions is also a key factor in LLPS. In this work we build a LLPS predictor which combines the ability to form pi-pi interactions, with an unrelated feature, the propensity to stabilize the β-pairing interaction mode. The cross-β structure is formed in the amyloid aggregates, which are involved in degenerative diseases and may be the final thermodynamically stable state of protein condensates. Our results show that the combination of pi-pi and β-pairing propensity yields an improved performance. They also suggest that protein sequences are more likely to be involved in phase separation if the main chain conformational entropy of the β-pairing maintained droplet state is increased. This would stabilize the droplet state against the more ordered amyloid state. Interestingly, the entropic stabilization of the droplet state appears to proceed according to different mechanisms, depending on the fraction of "droplet-driving" proteins present in the positive set.
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Yan C, Wang C, Shao X, Teng Y, Chen P, Hu X, Guan P, Wu H. Multifunctional Carbon-Dot-Photosensitizer Nanoassemblies for Inhibiting Amyloid Aggregates, Suppressing Microbial Infection, and Overcoming the Blood-Brain Barrier. ACS Appl Mater Interfaces 2022; 14:47432-47444. [PMID: 36254877 DOI: 10.1021/acsami.2c14118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Amyloid aggregation, microbial infection, and the blood-brain barrier (BBB) are considered critical obstructions for the treatment of Alzheimer's disease (AD). At present, existing treatment strategies are rarely able to overcome these critical factors. Herein, we propose an innovative treatment strategy and design multifunctional nanoassemblies (yCDs-Ce6) from coassembling photosensitizers (chlorine e6) and yellow fluorescent carbon dots, which endow yCDs-Ce6 with the functions for photodynamic and photothermal therapy (PDT and PTT). Compared with reported inhibitors, yCDs-Ce6 can suppress amyloid aggregation for 7 days, disaggregate aggregates, reduce amyloid aggregation-induced cytotoxicity, and prevent microbial growth by PDT and PTT. Moreover, yCDs-Ce6 can specifically target amyloid aggregates and visually label amyloid aggregates. yCDs-Ce6 can also cross the BBB upon near-infrared light irradiation and clear amyloid deposition in APP/PS1 mice by PDT and PTT. Meanwhile, yCDs-Ce6 did not cause significant negative effects on normal cells or tissues. Based on the methods of PPT and PTT treatment, the research deeply explores the effect of the novel nanoassemblies on two hypotheses of AD, opening a novel therapeutic paradigm for research amyloid-related diseases.
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Affiliation(s)
- Chaoren Yan
- School of Medicine, Key Laboratory for Molecular Genetic Mechanisms and Intervention Research on High Altitude Disease of Tibet Autonomous Region, Xizang Minzu University, Xianyang, Shaanxi 712082, China
- Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China
| | - Chaoli Wang
- Department of Pharmaceutical Chemistry and Analysis, School of Pharmacy, Air Force Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Xu Shao
- Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China
| | - Yonggang Teng
- Department of Pharmaceutical Chemistry and Analysis, School of Pharmacy, Air Force Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Peng Chen
- Department of Pharmaceutical Chemistry and Analysis, School of Pharmacy, Air Force Medical University, 169 Changle West Road, Xi'an 710032, China
| | - Xiaoling Hu
- Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China
| | - Ping Guan
- Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China
| | - Hong Wu
- Department of Pharmaceutical Chemistry and Analysis, School of Pharmacy, Air Force Medical University, 169 Changle West Road, Xi'an 710032, China
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Matveyenka M, Zhaliazka K, Rizevsky S, Kurouski D. Lipids uniquely alter secondary structure and toxicity of lysozyme aggregates. FASEB J 2022; 36:e22543. [PMID: 36094052 PMCID: PMC10427241 DOI: 10.1096/fj.202200841r] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/03/2022] [Accepted: 08/29/2022] [Indexed: 08/17/2023]
Abstract
Abrupt aggregation of misfolded proteins is a hallmark of the large group of amyloid pathologies that include diabetes type 2, Alzheimer and Parkinson's diseases. Protein aggregation yields oligomers and fibrils, β-sheet-rich structures that exert cell toxicity. Microscopic examination of amyloid deposits reveals the presence of lipids membranes, which suggests that lipids can be involved in the process of pathogenic protein assembly. In this study, we show that lipids can uniquely alter the aggregation rates of lysozyme, a protein that is associated with systemic amyloidosis. Specifically, cardiolipin (CL), ceramide (CER), and sphingomyelin (SM) accelerate, phosphatidylcholine (PC) strongly inhibits, whereas phosphatidylserine (PS) has no effect on the rate of protein aggregation. Furthermore, lipids uniquely alter the secondary structure of lysozyme aggregates. Furthermore, we found that lysozyme aggregates grown in the presence of CL, CER, SM, PS, and CL:PC mixtures exert significantly lower production of reactive oxygen species and mitochondrial dysfunction compared to lysozyme:PC aggregates and lysozyme fibrils grown in the lipid-free environment. These findings suggest that a change in the lipid composition of cell membranes, which is taken place upon neurodegeneration, may trigger the formation of toxic protein species that otherwise would not be formed.
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Affiliation(s)
- Mikhail Matveyenka
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Kiryl Zhaliazka
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Stanislav Rizevsky
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
- Department of Biotechnology, Binh Duong University, Thu Dau Mot, Vietnam
| | - Dmitry Kurouski
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas, USA
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Han K, Feng G, Li T, Deng Z, Zhang Z, Wang J, Yang X. Digestion Resistance of Soybean 7S Protein and Its Implications for Reinforcing the Gastric Mucus Barrier. J Agric Food Chem 2022; 70:8776-8787. [PMID: 35802804 DOI: 10.1021/acs.jafc.2c02603] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Previous studies have found that soybean protein, especially soybean 7S protein (β-conglycinin), exhibits digestion resistance, but the mechanism of digestion resistance and its implications for human health are still unclear. Here, we show that the extracted soybean 7S protein contains both oligomer globulins and amyloid aggregates, while the gastric digested soybean 7S protein only contains amyloid aggregates and thus exhibits digestion resistance. An animal experiment shows that un-digestible soybean 7S protein effectively prevents aspirin-induced acute gastric mucosa damage. The impacts of un-digestible soybean 7S protein on gastric mucus barrier properties are investigated using quartz crystal microbalance with dissipation (QCM-D), Langmuir monolayer, and multiple particle tracking (MPT). Results show that these un-digestible protein aggregates can penetrate into gastric mucus, increase the viscosity and compactness of the mucin layer, and reinforce the gastric mucus barrier properties. The findings are helpful to understand that high consumption of non-fermented soybean foods is associated with a decreased risk of gastric cancer.
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Affiliation(s)
- Kaining Han
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
| | - Guangxin Feng
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
| | - Tanghao Li
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
| | - Zhuoyao Deng
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
| | - Zhao Zhang
- Guangdong Longsee Biomedical Co.,Ltd., Guangzhou 510700, China
| | - Jinmei Wang
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
| | - Xiaoquan Yang
- Laboratory of Food Proteins and Colloids, School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510641, China
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Fanni AM, Okoye D, Monge FA, Hammond J, Maghsoodi F, Martin TD, Brinkley G, Phipps ML, Evans DG, Martinez JS, Whitten DG, Chi EY. Controlled and Selective Photo-oxidation of Amyloid-β Fibrils by Oligomeric p-Phenylene Ethynylenes. ACS Appl Mater Interfaces 2022; 14:14871-14886. [PMID: 35344326 PMCID: PMC10452927 DOI: 10.1021/acsami.1c22869] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photodynamic therapy (PDT) has been explored as a therapeutic strategy to clear toxic amyloid aggregates involved in neurodegenerative disorders such as Alzheimer's disease. A major limitation of PDT is off-target oxidation, which can be lethal for the surrounding cells. We have shown that a novel class of oligo-p-phenylene ethynylenes (OPEs) exhibit selective binding and fluorescence turn-on in the presence of prefibrillar and fibrillar aggregates of disease-relevant proteins such as amyloid-β (Aβ) and α-synuclein. Concomitant with fluorescence turn-on, OPE also photosensitizes singlet oxygen under illumination through the generation of a triplet state, pointing to the potential application of OPEs as photosensitizers in PDT. Herein, we investigated the photosensitizing activity of an anionic OPE for the photo-oxidation of Aβ fibrils and compared its efficacy to the well-known but nonselective photosensitizer methylene blue (MB). Our results show that, while MB photo-oxidized both monomeric and fibrillar conformers of Aβ40, OPE oxidized only Aβ40 fibrils, targeting two histidine residues on the fibril surface and a methionine residue located in the fibril core. Oxidized fibrils were shorter and more dispersed but retained the characteristic β-sheet rich fibrillar structure and the ability to seed further fibril growth. Importantly, the oxidized fibrils displayed low toxicity. We have thus discovered a class of novel theranostics for the simultaneous detection and oxidization of amyloid aggregates. Importantly, the selectivity of OPE's photosensitizing activity overcomes the limitation of off-target oxidation of traditional photosensitizers and represents an advancement of PDT as a viable strategy to treat neurodegenerative disorders.
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Affiliation(s)
- Adeline M. Fanni
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
- Biomedical Engineering Graduate Program, University of New Mexico, Albuquerque, NM. 87131
| | - Daniel Okoye
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
| | - Florencia A. Monge
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
- Biomedical Engineering Graduate Program, University of New Mexico, Albuquerque, NM. 87131
| | - Julia Hammond
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM. 87131
- Rose-Hulman Institute of Technology, Terre Haute, IN 47803
| | - Fahimeh Maghsoodi
- Nanoscience and Microsystems Engineering Graduate Program, University of New Mexico, Albuquerque, NM 87131
| | - Tye D. Martin
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
- Biomedical Engineering Graduate Program, University of New Mexico, Albuquerque, NM. 87131
| | - Gabriella Brinkley
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM. 87131
- Chemical Engineering Department, University of Minnesota, Duluth, MN 55812
| | - M. Lisa Phipps
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545
| | - Deborah G. Evans
- Department of Chemistry and Chemical Biology, University of New Mexico, NM 87131
| | - Jennifer S. Martinez
- Center for Materials Interfaces in Research and Applications, Northern Arizona University, Flagstaff, AZ 86011
- Department of Applied Physics and Materials Science, Northern Arizona University, Flagstaff, AZ 86011
| | - David G. Whitten
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM. 87131
| | - Eva Y. Chi
- Center for Biomedical Engineering, University of New Mexico, Albuquerque, NM 87131
- Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM. 87131
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Cao Y, He Z, Gao Y, Xin Y, Luo L, Meng F. Boosting the Photodynamic Degradation of Islet Amyloid Polypeptide Aggregates Via a "Bait-Hook-Devastate" Strategy. ACS Appl Mater Interfaces 2021; 13:14911-14919. [PMID: 33764749 DOI: 10.1021/acsami.1c00082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Photosensitizers that can generate reactive oxygen species (ROS) upon irradiation have emerged as promising agents for photodynamic degradation of toxic amyloid aggregates that are linked to many amyloidogenic diseases. However, due to the ultrastable β-sheet structure in amyloid aggregates and inefficient utilization of the generated ROS, it usually requires high stoichiometric concentration of the photosensitizer and/or intensive light irradiation to fully dissociate aggregates. In this work, we have developed a "bait-hook-devastate" strategy to boost the efficiency of the photodynamic degradation of amyloid aggregates. This strategy employs anionic polyacrylic acid as a bait to accumulate cationic human islet amyloid polypeptide (IAPP) aggregates and positively charged photosensitizer TPCI in a confined area through electronic interactions. Multiple characterization studies proved that the utilization rate of ROS generated by TPCI was remarkably improved via this strategy, which amplified the ability of TPCI to dissociate IAPP aggregates. Rapid and complete degradation of IAPP aggregates could be achieved by irradiating the system under very mild conditions for less than 30 min, and the IAPP-mediated cytotoxicity was also largely alleviated, providing a new paradigm to accelerate photodynamic degradation of amyloid aggregates for further practical applications.
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Affiliation(s)
- Yujuan Cao
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhenyan He
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yuting Gao
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yanru Xin
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Liang Luo
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fanling Meng
- National Engineering Research Center for Nanomedicine, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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Balasco N, Diaferia C, Morelli G, Vitagliano L, Accardo A. Amyloid-Like Aggregation in Diseases and Biomaterials: Osmosis of Structural Information. Front Bioeng Biotechnol 2021; 9:641372. [PMID: 33748087 PMCID: PMC7966729 DOI: 10.3389/fbioe.2021.641372] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 12/14/2020] [Accepted: 02/05/2021] [Indexed: 11/13/2022] Open
Abstract
The discovery that the polypeptide chain has a remarkable and intrinsic propensity to form amyloid-like aggregates endowed with an extraordinary stability is one of the most relevant breakthroughs of the last decades in both protein/peptide chemistry and structural biology. This observation has fundamental implications, as the formation of these assemblies is systematically associated with the insurgence of severe neurodegenerative diseases. Although the ability of proteins to form aggregates rich in cross-β structure has been highlighted by recent studies of structural biology, the determination of the underlying atomic models has required immense efforts and inventiveness. Interestingly, the progressive molecular and structural characterization of these assemblies has opened new perspectives in apparently unrelated fields. Indeed, the self-assembling through the cross-β structure has been exploited to generate innovative biomaterials endowed with promising mechanical and spectroscopic properties. Therefore, this structural motif has become the fil rouge connecting these diversified research areas. In the present review, we report a chronological recapitulation, also performing a survey of the structural content of the Protein Data Bank, of the milestones achieved over the years in the characterization of cross-β assemblies involved in the insurgence of neurodegenerative diseases. A particular emphasis is given to the very recent successful elucidation of amyloid-like aggregates characterized by remarkable molecular and structural complexities. We also review the state of the art of the structural characterization of cross-β based biomaterials by highlighting the benefits of the osmosis of information between these two research areas. Finally, we underline the new promising perspectives that recent successful characterizations of disease-related amyloid-like assemblies can open in the biomaterial field.
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Affiliation(s)
- Nicole Balasco
- Institute of Biostructures and Bioimaging (IBB), CNR, Naples, Italy
| | - Carlo Diaferia
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples “Federico II”, Naples, Italy
| | - Giancarlo Morelli
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples “Federico II”, Naples, Italy
| | - Luigi Vitagliano
- Institute of Biostructures and Bioimaging (IBB), CNR, Naples, Italy
| | - Antonella Accardo
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples “Federico II”, Naples, Italy
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Davoudi M, Moradi-Sardareh H, Emamgholipour S, Nabatchian F, Paknejad M. The possible effect of silver nanoparticles on glyceraldehyde-3-phosphate dehydrogenase activity and formation of amyloid-like aggregates in MCF-7 cell line. IUBMB Life 2020; 72:2214-2224. [PMID: 32819028 DOI: 10.1002/iub.2362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 05/28/2020] [Revised: 07/02/2020] [Accepted: 07/08/2020] [Indexed: 11/06/2022]
Abstract
Silver nanoparticles (AgNPs) are widely used in medicine, however, the underlying mechanisms of their action on cellular signaling have not been completely determined, and fundamental studies are required to clarify them. We aimed to investigate AgNPs effects on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as both the internal control gene and the redox-sensitive enzyme involved in apoptosis-related pathways and the formation of amyloid aggregates. To achieve this purpose, MCF-7 cells were treated with different concentrations (0, 3, 22, and 200 μg/ml) of AgNPs and then cell viability, generation of reactive oxygen species (ROS), induction of apoptosis, expression of GAPDH gene, the formation of amyloid aggregates, and GAPDH activity were assessed. The results indicated that treatment with AgNPs significantly reduced cell viability and increased apoptosis in a dose-dependent manner. The ROS levels increased at lower concentrations of AgNPs (up to 22 μg/ml) and during short-term exposure (30 min). The level of GAPDH gene expression was significantly upregulated by 1.22, 1.47, and 1.56 fold, in the concentrations of 3, 22, and 200 μg/ml, respectively. The amount of amyloid aggregates was significantly increased in a dose-dependent manner. The results of enzyme activity showed that AgNPs were affected on the activity of GAPDH protein, however, it has fluctuated that could not be interpreted by our limited data. In conclusion, our results suggested that AgNPs could affect the GAPDH gene expression and enzyme activity, therefore the selection of GAPDH as a gene and protein internal control in the (AgNPs)-related studies requires careful consideration. Additionally, AgNPs may cause apoptosis due to the increase in the production of amyloid aggregates.
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Affiliation(s)
- Maryam Davoudi
- Department of Medical Laboratory, School of Allied Health Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Hemen Moradi-Sardareh
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Solaleh Emamgholipour
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fariba Nabatchian
- Department of Medical Laboratory, School of Allied Health Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Maliheh Paknejad
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Zhang Y, Xu L, Chang Y, Li Y, Butler W, Jin E, Wang A, Tao Y, Chen X, Liang C, Huang J. Therapeutic potential of ReACp53 targeting mutant p53 protein in CRPC. Prostate Cancer Prostatic Dis 2020; 23:160-71. [PMID: 31471556 DOI: 10.1038/s41391-019-0172-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/19/2019] [Accepted: 07/28/2019] [Indexed: 01/01/2023]
Abstract
BACKGROUNDS p53 is a tumor suppressor that prevents cancer onset and progression, and mutations in the p53 gene cause loss of the tumor suppressor function of the protein. The mutant p53 protein in tumor cells can form aggregates which contribute to the dominant-negative effect over the wild-type p53 protein, causing loss of p53 tumor suppression or gain of novel oncogenic functions. Mutations in p53 have been implicated in the pathogenesis of primary prostate cancer (PCa), and are often detected in recurrent and metastatic disease. Thus, targeting mutant p53 may constitute an alternative therapeutic strategy for advanced PCa for which there are no other viable options. METHODS In this study, we used immunoprecipitation, immunofluorescence, clonogenic survival, and cell proliferation assays, flow cytometric analysis and in vivo xenograft to investigate the biological effects of ReACp53, a cell-permeable peptide inhibitor of p53 aggregation, on mutant p53-carrying PCa cells. RESULTS Our results show that ReACp53 targets amyloid aggregates of mutant p53 protein and restores the p53 nuclear function as transcriptional factor, induces mitochondrial cell death and reduces DNA synthesis of mutant p53-carrying PCa cells; ReACp53 also inhibits xenograft tumor growth in vivo. CONCLUSIONS The data presented here suggest a therapeutic potential of targeting mutant p53 protein in advanced PCa setting, which has a clinical impact for aggressive PCa with transforming how such tumors are managed.
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Ruotolo R, De Giorgio G, Minato I, Bianchi MG, Bussolati O, Marmiroli N. Cerium Oxide Nanoparticles Rescue α-Synuclein-Induced Toxicity in a Yeast Model of Parkinson's Disease. Nanomaterials (Basel) 2020; 10:E235. [PMID: 32013138 DOI: 10.3390/nano10020235] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/25/2020] [Accepted: 01/26/2020] [Indexed: 12/21/2022]
Abstract
Over the last decades, cerium oxide nanoparticles (CeO2 NPs) have gained great interest due to their potential applications, mainly in the fields of agriculture and biomedicine. Promising effects of CeO2 NPs are recently shown in some neurodegenerative diseases, but the mechanism of action of these NPs in Parkinson's disease (PD) remains to be investigated. This issue is addressed in the present study by using a yeast model based on the heterologous expression of the human α-synuclein (α-syn), the major component of Lewy bodies, which represent a neuropathological hallmark of PD. We observed that CeO2 NPs strongly reduce α-syn-induced toxicity in a dose-dependent manner. This effect is associated with the inhibition of cytoplasmic α-syn foci accumulation, resulting in plasma membrane localization of α-syn after NP treatment. Moreover, CeO2 NPs counteract the α-syn-induced mitochondrial dysfunction and decrease reactive oxygen species (ROS) production in yeast cells. In vitro binding assay using cell lysates showed that α-syn is adsorbed on the surface of CeO2 NPs, suggesting that these NPs may act as a strong inhibitor of α-syn toxicity not only acting as a radical scavenger, but through a direct interaction with α-syn in vivo.
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Anand BG, Prajapati KP, Dubey K, Ahamad N, Shekhawat DS, Rath PC, Joseph GK, Kar K. Self-Assembly of Artificial Sweetener Aspartame Yields Amyloid-like Cytotoxic Nanostructures. ACS Nano 2019; 13:6033-6049. [PMID: 31021591 DOI: 10.1021/acsnano.9b02284] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Recent reports have revealed the intrinsic propensity of single aromatic metabolites to undergo self-assembly and form nanostructures of amyloid nature. Hence, identifying whether aspartame, a universally consumed artificial sweetener, is inherently aggregation prone becomes an important area of investigation. Although the reports on aspartame-linked side effects describe a multitude of metabolic disorders, the mechanistic understanding of such destructive effects is largely mysterious. Since aromaticity, an aggregation-promoting factor, is intrinsic to aspartame's chemistry, it is important to know whether aspartame can undergo self-association and if such a property can predispose any cytotoxicity to biological systems. Our study finds that aspartame molecules, under mimicked physiological conditions, undergo a spontaneous self-assembly process yielding regular β-sheet-like cytotoxic nanofibrils of amyloid nature. The resultant aspartame fibrils were found to trigger amyloid cross-seeding and become a toxic aggregation trap for globular proteins, Aβ peptides, and aromatic metabolites that convert native structures to β-sheet-like fibrils. Aspartame fibrils were also found to induce hemolysis, causing DNA damage resulting in both apoptosis and necrosis-mediated cell death. Specific spatial arrangement between aspartame molecules is predicted to form a regular amyloid-like architecture with a sticky exterior that is capable of promoting viable H-bonds, electrostatic interactions, and hydrophobic contacts with biomolecules, leading to the onset of protein aggregation and cell death. Results reveal that the aspartame molecule is inherently amyloidogenic, and the self-assembly of aspartame becomes a toxic trap for proteins and cells, exposing the bitter side of such a ubiquitously used artificial sweetener.
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Affiliation(s)
- Bibin Gnanadhason Anand
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | | | - Kriti Dubey
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Naseem Ahamad
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Dolat Singh Shekhawat
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | - Pramod Chandra Rath
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - George Kodimattam Joseph
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | - Karunakar Kar
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
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Fichou Y, Lin Y, Rauch JN, Vigers M, Zeng Z, Srivastava M, Keller TJ, Freed JH, Kosik KS, Han S. Cofactors are essential constituents of stable and seeding-active tau fibrils. Proc Natl Acad Sci U S A 2018; 115:13234-9. [PMID: 30538196 DOI: 10.1073/pnas.1810058115] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Amyloid fibrils are cross-β-rich aggregates that are exceptionally stable forms of protein assembly. Accumulation of tau amyloid fibrils is involved in many neurodegenerative diseases, including Alzheimer's disease (AD). Heparin-induced aggregates have been widely used and assumed to be a good tau amyloid fibril model for most biophysical studies. Here we show that mature fibrils made of 4R tau variants, prepared with heparin or RNA, spontaneously depolymerize and release monomers when their cofactors are removed. We demonstrate that the cross-β-sheet assembly formed in vitro with polyanion addition is unstable at room temperature. We furthermore demonstrate high seeding capacity with transgenic AD mouse brain-extracted tau fibrils in vitro that, however, is exhausted after one generation, while supplementation with RNA cofactors resulted in sustained seeding over multiple generations. We suggest that tau fibrils formed in brains are supported by unknown cofactors and inhere higher-quality packing, as reflected in a more distinct conformational arrangement in the mouse fibril-seeded, compared with heparin-induced, tau fibrils. Our study suggests that the role of cofactors in tauopathies is a worthy focus of future studies, as they may be viable targets for diagnosis and therapeutics.
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Abstract
The appearance of protein aggregates is a hallmark of several pathologies including many neurodegenerative diseases. Mounting evidence suggests that the accumulation of misfolded proteins into inclusions is a secondary line of defense when the extent of protein misfolding exceeds the capacity of the Protein Quality Control System, which mediates refolding or degradation of misfolded species. Such exhaustion can occur during severe proteotoxic stress, the excessive occurrence of aggregation prone protein species, e.g., amyloids, or during ageing. However, the machinery that mediates recognition, recruitment and deposition of different types of misfolded proteins into specific deposition sites is only poorly understood. Since emerging principles of aggregate deposition appear evolutionarily conserved, yeast represents a powerful model to study basic mechanisms of recognition of different types of misfolded proteins, their recruitment to the respective deposition site and the molecular organization at the corresponding site. Yeast possesses at least three different aggregate deposition sites, one of which is a major deposition site for amyloid aggregates termed Insoluble PrOtein Deposit (IPOD). Due to the link between neurodegenerative disease and accumulation of amyloid aggregates, the IPOD is of particular interest when we aim to identify the molecular mechanisms that cells have evolved to counteract toxicity associated with the occurrence of amyloid aggregates. Here, we will review what is known about IPOD composition and the mechanisms of recognition and recruitment of amyloid aggregates to this site in yeast. Finally, we will briefly discuss the possible physiological role of aggregate deposition at the IPOD.
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Affiliation(s)
- Stephanie Rothe
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
| | - Abaya Prakash
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
| | - Jens Tyedmers
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
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Debnath S, Nath B, Chakrabarti A. Flow Cytometric Analysis of Protein Aggregates. Protein Pept Lett 2017; 24:969-973. [PMID: 28820064 DOI: 10.2174/0929866524666170818155030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 04/21/2017] [Revised: 06/16/2017] [Accepted: 06/16/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Misfolding of proteins often leads to aggregation. Accumulation of diverse protein aggregates in various cells, tissue and organs is the hallmark of many diseases, such as Alzheimer's disease and Parkinson's disease. OBJECTIVES The main objective of this study was to present a novel method of characterization of protein aggregates, associated with differential toxicity with different size and composition in vitro using flow cytometry. METHODS A Beckman Coulter Epics XL flow cytometer with argon ion laser operating at 488 nm was used for flow cytometry analysis. The voltage and the gain settings for individual channels were set at high voltage and gain for the detections of autofluorescence, fluorescence of adsorbed Congo red, forward scattering (FSC) and side scattering (SSC) intensities from the aggregates of proteins and nanoparticles. Each sample was analyzed to characterize and quantify the number of aggregates with a limit of maximum 20,000 events. The flow cytometry data were analyzed using Flowing software version 2.5.1 and Origin 8.0. RESULTS Autofluorescence and scattering intensities could distinguish between amyloid and nonamyloid aggregates. Dot plots of both side scattering (SSC) and forward scattering (FSC) intensities also showed characteristic fingerprint of both the types of aggregates when compared with those of well known nanoparticles of oxides of Fe and Cu. CONCLUSION This work reports a novel, simple and robust flow cytometric method of characterization of protein aggregates of different size and composition which would find wider application in characterization of biomolecular aggregates, in general.
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Affiliation(s)
- Sushanta Debnath
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata. India
| | - Bikram Nath
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata. India
| | - Abhijit Chakrabarti
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, HBNI, Kolkata. India
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Abstract
Sequestration of aggregates into specialized deposition sites occurs in many species across all kingdoms of life ranging from bacteria to mammals and is commonly believed to have a cytoprotective function. Yeast cells possess at least 3 different spatially separated deposition sites, one of which is termed “Insoluble Protein Deposit (IPOD)” and harbors amyloid aggregates. We have recently discovered that recruitment of amyloid aggregates to the IPOD uses an actin cable based recruitment machinery that also involves vesicular transport.1 Here we discuss how different proteins known to be involved in vesicular transport processes to the vacuole might act to guide amyloid aggregates to the IPOD. These factors include the Myosin V motor protein Myo2 involved in transporting vacuolar vesicles along actin cables, the transmembrane protein Atg9 involved in the recruitment of large precursor hydrolase complexes to the vacuole, the phosphatidylinositol/ phosphatidylcholine (PI/PC) transfer protein Sec 14 and the SNARE chaperone Sec 18. Furthermore, we present new data suggesting that the yeast dynamin homolog Vps1 is also crucial for faithful delivery of the amyloid model protein PrD-GFP to the IPOD. This is in agreement with a previously identified role for Vps1 in recruitment of heat-denatured aggregates to a perivacuolar deposition site.2
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Affiliation(s)
- Rajesh Kumar
- a Department of Medicine I and Clinical Chemistry , University Hospital Heidelberg , Heidelberg , Germany
| | - Nicole Neuser
- a Department of Medicine I and Clinical Chemistry , University Hospital Heidelberg , Heidelberg , Germany
| | - Jens Tyedmers
- a Department of Medicine I and Clinical Chemistry , University Hospital Heidelberg , Heidelberg , Germany
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19
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Hidalgo IH, Fleming T, Eckstein V, Herzig S, Nawroth PP, Tyedmers J. Characterization of aggregate load and pattern in living yeast cells by flow cytometry. Biotechniques 2016; 61:137-48. [PMID: 27625208 DOI: 10.2144/000114452] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/07/2016] [Indexed: 11/23/2022] Open
Abstract
Protein aggregation is both a hallmark of and a driving force for a number of diseases. It is therefore important to identify the nature of these aggregates and the mechanism(s) by which the cell counteracts their detrimental properties. Currently, the study of aggregation in vivo is performed primarily using fluorescently tagged versions of proteins and analyzing the aggregates by fluorescence microscopy. While this strategy is considered the gold standard, it has several limitations, particularly with respect to its suitability for high-throughput screening (HTS). Here, using a GFP fusion of the well-characterized yeast prion amyloid protein [PSI+], we demonstrate that flow cytometry, which utilizes the same physical principles as fluorescence microscopy, can be used to determine the aggregate load and pattern in live and fixed yeast cells. Furthermore, our approach can easily be applied to high-throughput analyses such as screenings with a yeast deletion library.
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Bobylev AG, Galzitskaya OV, Fadeev RS, Bobyleva LG, Yurshenas DA, Molochkov NV, Dovidchenko NV, Selivanova OM, Penkov NV, Podlubnaya ZA, Vikhlyantsev IM. Smooth muscle titin forms in vitro amyloid aggregates. Biosci Rep 2016; 36:e00334. [PMID: 27129292 DOI: 10.1042/BSR20160066] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 04/01/2016] [Indexed: 01/07/2023] Open
Abstract
Amyloids are insoluble fibrous protein aggregates, and their accumulation is associated with amyloidosis and many neurodegenerative diseases, including Alzheimer's disease. In the present study, we report that smooth muscle titin (SMT; 500 kDa) from chicken gizzard forms amyloid aggregates in vitro. This conclusion is supported by EM data, fluorescence analysis using thioflavin T (ThT), Congo red (CR) spectroscopy and X-ray diffraction. Our dynamic light scattering (DLS) data show that titin forms in vitro amyloid aggregates with a hydrodynamic radius (Rh) of approximately 700–4500 nm. The initial titin aggregates with Rh approximately 700 nm were observed beyond first 20 min its aggregation that shows a high rate of amyloid formation by this protein. We also showed using confocal microscopy the cytotoxic effect of SMT amyloid aggregates on smooth muscle cells from bovine aorta. This effect involves the disorganization of the actin cytoskeleton and result is cell damage. Cumulatively, our results indicate that titin may be involved in generation of amyloidosis in smooth muscles.
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Abstract
Prions are infectious proteins with altered conformations converted from otherwise normal host proteins. While there is only one known mammalian prion protein, PrP, a handful of prion proteins have been identified in the yeast Saccharomyces cerevisiae. Yeast prion proteins usually have a defined region called prion domain (PrD) essential for prion properties, which are typically rich in glutamine (Q) and asparagine (N). Despite sharing several common features, individual yeast PrDs are generally intricate and divergent in their compositional characteristics, which potentially implicates their prion phenotypes, such as prion-mediated transcriptional regulations.
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