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Chang CY, Wang SSS, Lai YR, Koh WG, Wu JW, Chiang YH. Ophthalmic drug effects on the amyloidogenesis of a transforming growth factor β-induced protein (TGFBIp) peptide fragment. Exp Eye Res 2024; 244:109932. [PMID: 38762008 DOI: 10.1016/j.exer.2024.109932] [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: 11/05/2023] [Revised: 03/30/2024] [Accepted: 05/15/2024] [Indexed: 05/20/2024]
Abstract
Drugs that can treat one disease may either be detrimental or beneficial toward another due to possible cross-interactions. Therefore, care in choosing a suitable drug for patients with multiple diseases is crucial in successful patient management. This study explores several currently available ophthalmic drugs used to treat common ocular diseases to understand how they can affect the amyloidogenesis of a transforming growth factor β-induced protein (TGFBIp) peptide fragment found in abundance in the corneal protein aggregation deposits of lattice corneal dystrophy (LCD) patients. Results from this study provided supporting evidence that some drugs intended to treat other diseases can enhance or inhibit fibrillar aggregation of TGFBIp peptide, which may have potential implication of affecting the disease progression of LCD by either worsening or ameliorating it. Comparisons of the different properties of ophthalmic compounds explored in this study may also provide some guidance for future design of drugs geared toward the treatment of LCD.
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Affiliation(s)
- Chia-Yu Chang
- Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Steven S-S Wang
- Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - You-Ren Lai
- Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Won-Gun Koh
- Department of Chemical and Biomolecular Engineering, Yonsei University, South Korea
| | - Josephine W Wu
- Department of Optometry, Yuanpei University of Medical Technology, Hsinchu City, 30015, Taiwan; Department of Optometry, Mackay Medical College, New Taipei City, 252, Taiwan.
| | - Yi-Hui Chiang
- Department of Ophthalmology, En Chu Kong Hospital, New Taipei City, 237, Taiwan.
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Fitzner L, Hasler M, Heyn TR, Schwarz K, Keppler JK. UVB pretreatment of β-lactoglobulin affects the temperature-induced formation of functional amyloid-like aggregates and promotes oxidative degradation. Food Chem 2023; 429:136898. [PMID: 37516047 DOI: 10.1016/j.foodchem.2023.136898] [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: 03/17/2023] [Revised: 06/11/2023] [Accepted: 07/14/2023] [Indexed: 07/31/2023]
Abstract
Unfolding in combination with or without acid hydrolysis is crucial for the formation of functional amyloid (fibrillar) or amyloid-like (worm-like) β-lactoglobulin (BLG) aggregates, which can be induced through temperature treatment for several hours at pH 2-4. A preceding conformational destabilization of BLG might affect its aggregation. We investigated ultraviolet (UV) B radiation as conformational perturbing treatment to facilitate temperature-induced protein aggregation. 2-h UVB pretreated BLG (UV-BLG) exhibited an accelerated worm-like aggregation at pH 3.5, while at pH 2 the formation of fibrils was decelerated. The UV-induced conformational destabilization lowered the thermal stability and thus facilitates unfolding during thermal treatment. Thereby, the formation of covalent and non-covalent intermolecular interactions was favored, which promoted assembly of intact proteins resulting in worm-like aggregates. The oxidative degradation of UV-BLG was suggested to alter fibrillation-prone protein regions and thereby impede peptide assembly.
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Affiliation(s)
- Laura Fitzner
- Institute of Human Nutrition and Food Science, Division Food Technology, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany.
| | - Mario Hasler
- Lehrfach Variationsstatistik, Christian-Albrechts-University of Kiel, Hermann-Rodewald-Strasse 9, 24118 Kiel, Germany.
| | - Timon R Heyn
- Institute of Human Nutrition and Food Science, Division Food Technology, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany.
| | - Karin Schwarz
- Institute of Human Nutrition and Food Science, Division Food Technology, Christian-Albrechts-University of Kiel, Heinrich-Hecht-Platz 10, 24118 Kiel, Germany.
| | - Julia Katharina Keppler
- Laboratory of Food Process Engineering, Wageningen University & Research, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
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Hsueh SS, Lu JH, Wu JW, Lin TH, Wang SSS. Protection of human γD-crystallin protein from ultraviolet C-induced aggregation by ortho-vanillin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 261:120023. [PMID: 34098480 DOI: 10.1016/j.saa.2021.120023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Cataract is known as one of the leading causes of vision impairment worldwide. While the detailed mechanism of cataratogenesis remains unclear, cataract is believed to be correlated with the aggregation and/or misfolding of human ocular lens proteins called crystallins. A 173-residue structural protein human γD-crystallin is a major γ-crystallin protein in the human eye lens and associated with the development of juvenile and mature-onset cataracts. This work is aimed at investigating the effect of a small molecule, e.g., ortho-vanillin, on human γD-crystallin aggregation upon exposure to ultraviolet-C irradiation. According to the findings of right-angle light scattering, transmission electron microscopy, and gel electrophoresis, ortho-vanillin was demonstrated to dose-dependently suppress ultraviolet-C-triggered aggregation of human γD-crystallin. Results from the synchronous fluorescence spectroscopy, tryptophan fluorescence quenching, and molecular docking studies revealed the structural change of γD-crystallin induced by the interaction/binding between ortho-vanillin and protein. We believe the outcome from this work may contribute to the development of potential therapeutics for cataract.
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Affiliation(s)
- Shu-Shun Hsueh
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Jian-Hong Lu
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Josephine W Wu
- Department of Optometry, Yuanpei University of Medical Technology, Hsinchu City 30015, Taiwan.
| | - Ta-Hsien Lin
- Basic Research Division, Medical Research Department, Taipei Veterans General Hospital, Taipei 11217, Taiwan; Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan.
| | - Steven S-S Wang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
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Investigating the effect of sugar-terminated nanoparticles on amyloid fibrillogenesis of β-lactoglobulin. Int J Biol Macromol 2020; 165:291-307. [PMID: 32961178 DOI: 10.1016/j.ijbiomac.2020.09.104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 08/19/2020] [Accepted: 09/14/2020] [Indexed: 11/22/2022]
Abstract
In vivo tissue deposition of fibrillar protein aggregates is the cause of several degenerative diseases. Evidence suggests that interfering with the pathology-associated amyloid fibrillogenesis by inhibitory molecules is envisaged as the primary therapeutic strategy. Amyloid fibril formation of proteins has been demonstrated to be influenced by nanoparticles/nanomaterials. As compared with their molecular form counterpart, this work examined the effect of sucrose-terminated nanoparticles on the in vitro amyloid fibrillogenesis and structural properties of β-lactoglobulin at pH 2.0 and 80 °C. ThT binding and electron microscopy results demonstrated that sucrose-terminated nanoparticles were able to suppress β-lactoglobulin fibrillogenesis in a concentration-dependent fashion. Importantly, sucrose-terminated nanoparticles showed better β-lactoglobulin fibril-inhibiting ability than sucrose molecules. ANS fluorescence and right-angle light scattering results showed reduced solvent exposure and decreased aggregation, respectively, in the β-lactoglobulin samples upon treatment with sucrose-terminated nanoparticles. Moreover, fluorescence quenching analyses revealed that the static quenching mechanism and formation of a non-fluorescent fluorophore-nanoparticle complex are involved in the nanoparticle-β-lactoglobulin interaction. We believe that the results from this study may suggest that the nanoparticle form of biocompatible sugar-related osmolytes may serve as effective inhibiting/suppressing agents toward protein fibrillogenesis.
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How SC, Hsin A, Chen GY, Hsu WT, Yang SM, Chou WL, Chou SH, Wang SSS. Exploring the influence of brilliant blue G on amyloid fibril formation of lysozyme. Int J Biol Macromol 2019; 138:37-48. [PMID: 31295491 DOI: 10.1016/j.ijbiomac.2019.07.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 06/28/2019] [Accepted: 07/07/2019] [Indexed: 12/19/2022]
Abstract
Evidence suggests that amyloid fibril mitigation/inhibition is considered a promising approach toward treating amyloid diseases. In this work, we first examined how amyloid fibrillogenesis of lysozyme was affected by BBG, a safe triphenylmethane compound with nice blood-brain-barrier-permeability, and found that shorter fibrillar species were formed in the lysozyme samples treated with BBG. Next, alterations in the features including the secondary as well as tertiary structure, extent of aggregation, and molecular distribution of lysozyme triggered by the addition of BBG were examined by various spectroscopic techniques, right-angle light scattering, dynamic light scattering, and SDS-PAGE. In addition, we have investigated how BBG affected the lysozyme fibril-induced cytotoxicity in SH-SY5Y cells. We found that a large quantity of shorter fibrillar species and more lysozyme monomers were present in the samples treated with BBG. Also, the addition of BBG rescued SH-SY5Y cells from cell death induced by amyloid fibrils of lysozyme. Finally, information about the binding sites and interacting forces involved in the BBG-lysozyme interaction was further explored using synchronous fluorescence and molecular docking approaches. Molecular docking results revealed that, apart from the hydrophobic interaction(s), hydrogen bonding, electrostatic interactions, and van der Waal forces may also be involved in the binding interaction.
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Affiliation(s)
- Su-Chun How
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Ai Hsin
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Guan-Yu Chen
- Department of Life Science, Fu-Jen Catholic University, Xinzhuang Dist., New Taipei City, Taiwan
| | - Wei-Tse Hsu
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Szu-Ming Yang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Wei-Lung Chou
- Department of Safety, Health and Environmental Engineering, Hungkuang University, Sha Lu, Taichung City 433, Taiwan.
| | - Shiu-Huey Chou
- Department of Life Science, Fu-Jen Catholic University, Xinzhuang Dist., New Taipei City, Taiwan.
| | - Steven S-S Wang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
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6
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UV radiation sensitivity of bovine serum albumin bound to silver nanoparticles. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2019. [DOI: 10.1016/j.jrras.2014.07.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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7
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Lu NH, How SC, Lin CY, Tsai SL, Bednarikova Z, Fedunova D, Gazova Z, Wu JW, Wang SSS. Examining the effects of dextran-based polymer-coated nanoparticles on amyloid fibrillogenesis of human insulin. Colloids Surf B Biointerfaces 2018; 172:674-683. [DOI: 10.1016/j.colsurfb.2018.09.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/24/2018] [Accepted: 09/12/2018] [Indexed: 10/28/2022]
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Nusrat S, Khan RH. Exploration of ligand-induced protein conformational alteration, aggregate formation, and its inhibition: A biophysical insight. Prep Biochem Biotechnol 2018; 48:43-56. [PMID: 29106330 DOI: 10.1080/10826068.2017.1387561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The association of protein aggregates with plentiful human diseases has fascinated studies regarding the biophysical characterization of protein misfolding and ultimately their aggregate formation mechanism. Protein-ligand interaction, their mechanism, conformational changes by ligands, and protein aggregate formation have been studied upon exploiting experimental techniques and computational methodologies. Such studies for the exploration of ligand-induced conformational changes in protein, misfolding and aggregation, has confirmed drastic progresses in the study of aggregate formation pathways. This review comprises of an inclusive description of contemporary experimental techniques as well as theoretical improvements in the interpretation of the conformational properties of protein. We have also discussed various factors responsible for the microenvironment change around protein that sequentially causes amyloidoses. Biophysical techniques and cell-based assays to gain comprehensive understandings of protein-ligand interaction, protein folding, and aggregation pathways have also been described. The promising therapeutic methods used to inhibit the protein fibrillogenesis have also been discussed.
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Affiliation(s)
- Saima Nusrat
- a Interdisciplinary Biotechnology Unit , Aligarh Muslim University , Aligarh , Uttar Pradesh , India
| | - Rizwan Hasan Khan
- a Interdisciplinary Biotechnology Unit , Aligarh Muslim University , Aligarh , Uttar Pradesh , India
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Chen YH, Tseng CP, How SC, Lo CH, Chou WL, Wang SSS. Amyloid fibrillogenesis of lysozyme is suppressed by a food additive brilliant blue FCF. Colloids Surf B Biointerfaces 2016; 142:351-359. [DOI: 10.1016/j.colsurfb.2016.02.064] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/26/2016] [Accepted: 02/29/2016] [Indexed: 12/30/2022]
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Chang CK, Chen WA, Sie CY, Lin SC, Lin LTW, Lin TH, Hsu CC, Wang SSS. Investigating the effects of plasma pretreatment on the formation of ordered aggregates of lysozyme. Colloids Surf B Biointerfaces 2015; 126:154-61. [DOI: 10.1016/j.colsurfb.2014.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 12/05/2014] [Accepted: 12/09/2014] [Indexed: 11/30/2022]
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Carmo-Gonçalves P, Pinheiro AS, Romão L, Cortines J, Follmer C. UV-induced selective oxidation of Met5 to Met-sulfoxide leads to the formation of neurotoxic fibril-incompetent α-synuclein oligomers. Amyloid 2014; 21:163-74. [PMID: 24784227 DOI: 10.3109/13506129.2014.912208] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Oxidative stress and the formation of cytotoxic aggregates of the presynaptic protein α-synuclein (AS) are two important events associated with the pathogenesis of Parkinson's disease (PD) and several other neurodegenerative diseases. In this context, extensive efforts have been made to elucidate the molecular basis of the cytotoxic synergy between oxidative stress and AS aggregation. In this study, we demonstrate that the exposure of AS to oxidative stress induced by UV radiation (ASUV) blocks the protein fibrillation, leading to the formation of highly toxic fibril-incompetent oligomers. In addition, ASUV exhibited stronger anti-fibrillogenic properties than H2O2-treated AS, inhibiting the fibrillation of unmodified AS at notably low concentrations. Mass spectrometry indicated that Met5 oxidation to Met-sulfoxide was the only modification promoted by UV exposure, which is reinforced by NMR data indicating that Met5 is the only residue whose amide resonance completely disappeared from the (1)H-(15)N HSQC spectrum after UV exposure. This result is supported by previous data that indicate that C-terminal Met residues (Met116 and Met127) and N-terminal Met1 are less susceptible to oxidation than Met5 because of the residual structure of the disordered AS monomer. Overall, our findings suggest that specific oxidation of Met5 might be sufficient to promote the formation of highly neurotoxic oligomers of AS.
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Investigation of the inhibitory effects of TiO2 on the β-amyloid peptide aggregation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 39:227-34. [DOI: 10.1016/j.msec.2014.03.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/12/2014] [Accepted: 03/01/2014] [Indexed: 11/21/2022]
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Wu JWR, Kao CY, Lin LTW, Wen WS, Lai JT, Wang SSS. Human γD-crystallin aggregation induced by ultraviolet C irradiation is suppressed by resveratrol. Biochem Eng J 2013. [DOI: 10.1016/j.bej.2013.03.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Thakur AK, Srivastava AK, Srinivas V, Chary KVR, Rao CM. Copper alters aggregation behavior of prion protein and induces novel interactions between its N- and C-terminal regions. J Biol Chem 2011; 286:38533-38545. [PMID: 21900252 DOI: 10.1074/jbc.m111.265645] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Copper is reported to promote and prevent aggregation of prion protein. Conformational and functional consequences of Cu(2+)-binding to prion protein (PrP) are not well understood largely because most of the Cu(2+)-binding studies have been performed on fragments and truncated variants of the prion protein. In this context, we set out to investigate the conformational consequences of Cu(2+)-binding to full-length prion protein (PrP) by isothermal calorimetry, NMR, and small angle x-ray scattering. In this study, we report altered aggregation behavior of full-length PrP upon binding to Cu(2+). At physiological temperature, Cu(2+) did not promote aggregation suggesting that Cu(2+) may not play a role in the aggregation of PrP at physiological temperature (37 °C). However, Cu(2+)-bound PrP aggregated at lower temperatures. This temperature-dependent process is reversible. Our results show two novel intra-protein interactions upon Cu(2+)-binding. The N-terminal region (residues 90-120 that contain the site His-96/His-111) becomes proximal to helix-1 (residues 144-147) and its nearby loop region (residues 139-143), which may be important in preventing amyloid fibril formation in the presence of Cu(2+). In addition, we observed another novel interaction between the N-terminal region comprising the octapeptide repeats (residues 60-91) and helix-2 (residues 174-185) of PrP. Small angle x-ray scattering studies of full-length PrP show significant compactness upon Cu(2+)-binding. Our results demonstrate novel long range inter-domain interactions of the N- and C-terminal regions of PrP upon Cu(2+)-binding, which might have physiological significance.
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Affiliation(s)
- Abhay Kumar Thakur
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad 500 007, India
| | - Atul Kumar Srivastava
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Volety Srinivas
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad 500 007, India
| | - Kandala Venkata Ramana Chary
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Chintalagiri Mohan Rao
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad 500 007, India.
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Wang SSS, Hung YT, Wen WS, Lin KC, Chen GY. Exploring the inhibitory activity of short-chain phospholipids against amyloid fibrillogenesis of hen egg-white lysozyme. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:301-13. [DOI: 10.1016/j.bbalip.2011.02.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 01/22/2011] [Accepted: 02/04/2011] [Indexed: 01/27/2023]
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Wang SSS, Wen WS. Examining the influence of ultraviolet C irradiation on recombinant human γD-crystallin. Mol Vis 2010; 16:2777-90. [PMID: 21197112 PMCID: PMC3008712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 12/10/2010] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Human γD crystallin is a principal protein component of the human eye lens and associated with the development of juvenile and mature-onset cataracts. Exposure to ultraviolet (UV) light is thought to perturb protein structure and eventually lead to aggregation. This work is aimed at exploring the effects of UV-C irradiation on recombinant human γD-crystallin (HGDC). METHODS Recombinant HGDC proteins were expressed in E. coli strain BL21(DE3) harboring plasmid pEHisHGDC and purified using chromatographic methods. The proteins were then exposed to UV-C light (λ(max)=254 nm, 15 W) at the intensity of 420, 800, or 1850 μW/cm(2). The UV-C-unexposed, supernatant fraction of UV-C-exposed, and re-dissolved precipitated fraction of UV-C exposed preparations were characterized by SDS-PAGE, turbidity measurement, CD spectroscopy, tryptophan fluorescence spectroscopy, acrylamide fluorescence quenching analysis, and sulfhydryl group measurements. RESULTS The turbidity of the HGDC sample solution was found to be positively correlated with HGDC concentration, UV-C irradiation intensity, and UV-C irradiation duration. When exposed to UV-C, HGDC sample solutions became visibly turbid and a noticeable amount of larger protein particle, perceptible to the naked eye, was observed upon prolonged irradiation. The precipitated fraction of irradiated HGDC sample was found to be re-dissolved by guanidine hydrochloride. Electrophoresis, acrylamide fluorescence quenching, and spectroscopic analyses revealed differences in structures among the non-irradiated HGDC, the supernatant fraction of irradiated HGDC, and the re-dissolved precipitated fraction of irradiated HGDC. Through the use of L-cysteine, the measurements of sulfhydryl contents, and the reducing as well as non-reducing SDS-PAGE, our data further suggested that disulfide bond formation and/or cleavage probably play an important role in aggregation and/or precipitation of HGDC elicited by UV-C irradiation. CONCLUSIONS Our findings highlight the close connections among disulfide bond cleavage and/or formation, intermolecular interactions, and the resultant formation of aggregates of HGDC induced by UV-C irradiation. The results from this research may not only contribute to the understanding of the environmental factors causing protein aggregation but also have implications for deciphering the molecular mechanism of cataractogenesis.
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Wang SSS, Liu KN, Wang BW. Effects of dithiothreitol on the amyloid fibrillogenesis of hen egg-white lysozyme. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2010; 39:1229-42. [DOI: 10.1007/s00249-010-0576-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Revised: 12/03/2009] [Accepted: 01/13/2010] [Indexed: 10/19/2022]
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