1
|
Sun J, Matsubara T, Koide T, Lampi KJ, David LL, Takata T. Characterization of different-sized human αA-crystallin homomers and implications to Asp151 isomerization. PLoS One 2024; 19:e0306856. [PMID: 38991013 PMCID: PMC11238991 DOI: 10.1371/journal.pone.0306856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 06/25/2024] [Indexed: 07/13/2024] Open
Abstract
Site-specific modifications of aspartate residues spontaneously occur in crystallin, the major protein in the lens. One of the primary modification sites is Asp151 in αA-crystallin. Isomerization and racemization alter the crystallin backbone structure, reducing its stability by inducing abnormal crystallin-crystallin interactions and ultimately leading to the insolubilization of crystallin complexes. These changes are considered significant factors in the formation of senile cataracts. However, the mechanisms driving spontaneous isomerization and racemization have not been experimentally demonstrated. In this study, we generated αA-crystallins with different homo-oligomeric sizes and/or containing an asparagine residue at position 151, which is more prone to isomerization and racemization. We characterized their structure, hydrophobicity, chaperone-like function, and heat stability, and examined their propensity for isomerization and racemization. The results show that the two differently sized αA-crystallin variants possessed similar secondary structures but exhibited different chaperone-like functions depending on their oligomeric sizes. The rate of isomerization and racemization of Asp151, as assessed by the deamidation of Asn151, was also found to depend on the oligomeric sizes of αA-crystallin. The predominant isomerization product via deamidation of Asn151 in the different-sized αA-crystallin variants was L-β-Asp in vitro, while various modifications occurred around Asp151 in vivo. The disparity between the findings of this in vitro study and in vivo studies suggests that the isomerization of Asp151 in vivo may be more complex than what occurs in vitro.
Collapse
Affiliation(s)
- Jiayue Sun
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan
| | | | - Tamaki Koide
- Rexxam Corporation, Chuo-ku, Osaka-shi, Osaka, Japan
| | - Kirsten J. Lampi
- Oregon Health and Science University, Integrative Biosciences, Portland, Oregon, United States of America
| | - Larry L. David
- Oregon Health and Science University, Integrative Biosciences, Portland, Oregon, United States of America
| | - Takumi Takata
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori-cho, Sennan-gun, Osaka, Japan
| |
Collapse
|
2
|
Oncel D, Bal S, Mazon NKC, Smith Z, Marjane S, Gable E. Use of Informational Brochures on Knowledge of Cataracts in Rural Ecuador. Cureus 2023; 15:e35555. [PMID: 37007411 PMCID: PMC10060030 DOI: 10.7759/cureus.35555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2023] [Indexed: 03/03/2023] Open
Abstract
Background Cataracts are the leading global cause of preventable blindness. Despite the high prevalence of cataracts in rural Ecuadorian communities, no community-wide educational efforts on the impact of cataract-related blindness have been attempted. This study used an educational brochure to assess individual knowledge of cataract blindness before and after the distribution of the brochure. Methods We conducted electronic surveys with 100 patients over the age of 18 who visited the Fundacion Internacional Buen Samaritano Paul Martel (FIBUSPAM) clinic serving the Chimborazo region of Ecuador. Participation in the study included an introduction and written consent followed by a pre-survey. Every patient was given a brochure. After reviewing the brochure, patients were then asked to complete the same survey again. Each survey question received one mark. Knowledge was considered "good" if the subject correctly answered four out of seven questions and "poor" if they scored ≤3. Results Of the 100 patients, 21 had poor knowledge surrounding cataracts. Cataract awareness was lowest in the group without formal education (50%). In addition, 17 participants demonstrated poor knowledge before the informational brochure was distributed, and all improved to "good" knowledge after. Following brochure distribution, there was an improved knowledge of cataract anatomy (correct answer: 32.9% to 94.6%), treatment of cataracts (80% to 95.9%), cataract symptoms (36.7% to 95.9%), age at risk (88.8% to 97.3%), and relationship to blindness (93.5% to 98.6%). In contrast, overall knowledge of the risk factors for cataracts (46.8% to 37%) and prevention of the onset of the cataract (81.3% to 77%) slightly decreased after the brochure was given. Overall, the increase in the number of correct answers after the brochure was not significant (p = 0.25). Conclusions To our knowledge, this is a rare study to assess the effect of informational brochures on cataract knowledge in rural Ecuador. This study was limited by selection bias and did not look at the long-term recall of knowledge. The results of this study suggest that brochures can improve health awareness; however, brochures alone may not be enough. Additional assessments on the use of oral and visual aids are needed. Health education efforts should go beyond simple brochures and focus on innovative strategies to improve health education and communication efforts.
Collapse
|
3
|
TAKATA T. Identification of D-amino Acid Residues in Proteins Using Mass Spectrometry. BUNSEKI KAGAKU 2022. [DOI: 10.2116/bunsekikagaku.71.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Takumi TAKATA
- Institute for Integrated Radiation and Nuclear Science, Kyoto University
| |
Collapse
|
4
|
Li H, Yu Y, Ruan M, Jiao F, Chen H, Gao J, Weng Y, Bao Y. The mechanism for thermal-enhanced chaperone-like activity of α-crystallin against UV irradiation-induced aggregation of γD-crystallin. Biophys J 2022; 121:2233-2250. [PMID: 35619565 DOI: 10.1016/j.bpj.2022.05.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/11/2022] [Accepted: 05/20/2022] [Indexed: 11/18/2022] Open
Abstract
Exposure to solar UV irradiation damages γ-crystallin, leading to cataract formation via aggregation. α-Crystallin, as a small heat-shock protein (sHsps), efficiently suppresses this irreversible aggregation by selectively binding the denatured γ-crystallin monomer. In this study, liquid chromatography tandem mass spectrometry (LC-MS) was used to evaluate UV-325 nm irradiation-induced photodamage of human γD-crystallin in the presence of bovine α-crystallin, atomic force microscope (AFM) and dynamic light scattering (DLS) techniques were used to detect the quaternary structure changes of α-crystallin oligomer, and Fourier transform infrared (FTIR) spectroscopy and temperature-jump (T-jump) nanosecond time-resolved IR absorbance difference spectroscopy were used to probe the secondary structure changes of bovine α-crystallin. We find that the thermal-induced subunit dissociation of α-crystallin oligomer involves the breaking of hydrogen bonds at the dimeric interface, leading to three different spectral components at varied temperature regions as resolved from temperature-dependent IR spectra. Under UV-325 nm irradiation, unfolded γD-crystallin binds to the dissociated α-crystallin subunit to form αγ-complex, then follows the reassociation of αγ-complex to the partially dissociated α-crystallin oligomer. This prevents the aggregation of denatured γD-crystallin. The formation of the γD-bound α-crystallin oligomer is further confirmed by AFM and DLS analysis, which reveals an obvious size expansion in the reassociated αγ-oligomers. In addition, UV-325 nm irradiation causes a peptide bond cleavage of γD-crystallin at Ala158 in presence of α-crystallin. Our results suggest a very effective protection mechanism for subunits dissociated from α-crystallin oligomers against UV irradiation-induced aggregation of γD-crystallin, at an expense of a loss of a short C-terminal peptide in γD-crystallin.
Collapse
Affiliation(s)
- Hao Li
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; College of Chemical Biology and Biotechnology, Beijing University Shenzhen Graduate School, Shenzhen, China; Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yingying Yu
- Department of Ophthalmology, Peking University People's Hospital, Eye Diseases and Optometry Institute, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, College of Optometry, Peking University Health Science Center, Beijing, China
| | - Meixia Ruan
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Fang Jiao
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Hailong Chen
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jiali Gao
- College of Chemical Biology and Biotechnology, Beijing University Shenzhen Graduate School, Shenzhen, China; Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Yuxiang Weng
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Yongzhen Bao
- Department of Ophthalmology, Peking University People's Hospital, Eye Diseases and Optometry Institute, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, College of Optometry, Peking University Health Science Center, Beijing, China.
| |
Collapse
|
5
|
Yamamoto N, Takeda S, Hatsusaka N, Hiramatsu N, Nagai N, Deguchi S, Nakazawa Y, Takata T, Kodera S, Hirata A, Kubo E, Sasaki H. Effect of a Lens Protein in Low-Temperature Culture of Novel Immortalized Human Lens Epithelial Cells (iHLEC-NY2). Cells 2020; 9:cells9122670. [PMID: 33322631 PMCID: PMC7764252 DOI: 10.3390/cells9122670] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/27/2020] [Accepted: 12/11/2020] [Indexed: 11/24/2022] Open
Abstract
The prevalence of nuclear cataracts was observed to be significantly higher among residents of tropical and subtropical regions compared to those of temperate and subarctic regions. We hypothesized that elevated environmental temperatures may pose a risk of nuclear cataract development. The results of our in silico simulation revealed that in temperate and tropical regions, the human lens temperature ranges from 35.0 °C to 37.5 °C depending on the environmental temperature. The medium temperature changes during the replacement regularly in the cell culture experiment were carefully monitored using a sensor connected to a thermometer and showed a decrease of 1.9 °C, 3.0 °C, 1.7 °C, and 0.1 °C, after 5 min when setting the temperature of the heat plate device at 35.0 °C, 37.5 °C, 40.0 °C, and 42.5 °C, respectively. In the newly created immortalized human lens epithelial cell line clone NY2 (iHLEC-NY2), the amounts of RNA synthesis of αA crystallin, protein expression, and amyloid β (Aβ)1-40 secreted into the medium were increased at the culture temperature of 37.5 °C compared to 35.0 °C. In short-term culture experiments, the secretion of Aβ1-40 observed in cataracts was increased at 37.5 °C compared to 35.0 °C, suggesting that the long-term exposure to a high-temperature environment may increase the risk of cataracts.
Collapse
Affiliation(s)
- Naoki Yamamoto
- Department of Ophthalmology, Kanazawa Medical University, Ishikawa 920-0293, Japan; (N.Y.); (S.T.); (N.H.); (E.K.)
- Research Promotion and Support Headquarters, Fujita Health University, Aichi 470-1192, Japan;
| | - Shun Takeda
- Department of Ophthalmology, Kanazawa Medical University, Ishikawa 920-0293, Japan; (N.Y.); (S.T.); (N.H.); (E.K.)
| | - Natsuko Hatsusaka
- Department of Ophthalmology, Kanazawa Medical University, Ishikawa 920-0293, Japan; (N.Y.); (S.T.); (N.H.); (E.K.)
| | - Noriko Hiramatsu
- Research Promotion and Support Headquarters, Fujita Health University, Aichi 470-1192, Japan;
| | - Noriaki Nagai
- Faculty of Pharmacy, Kindai University, Osaka 577-8502, Japan; (N.N.); (S.D.)
| | - Saori Deguchi
- Faculty of Pharmacy, Kindai University, Osaka 577-8502, Japan; (N.N.); (S.D.)
| | - Yosuke Nakazawa
- Division of Hygienic Chemistry, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan;
| | - Takumi Takata
- Radiation Biochemistry, Division of Radiation Life Science, Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka 590-0494, Japan;
| | - Sachiko Kodera
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Aichi 466-8555, Japan; (S.K.); (A.H.)
| | - Akimasa Hirata
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Aichi 466-8555, Japan; (S.K.); (A.H.)
- Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Aichi 466-8555, Japan
| | - Eri Kubo
- Department of Ophthalmology, Kanazawa Medical University, Ishikawa 920-0293, Japan; (N.Y.); (S.T.); (N.H.); (E.K.)
| | - Hiroshi Sasaki
- Department of Ophthalmology, Kanazawa Medical University, Ishikawa 920-0293, Japan; (N.Y.); (S.T.); (N.H.); (E.K.)
- Correspondence: ; Tel.: +81-762-286-2211
| |
Collapse
|
6
|
Ying Y, Li H. Recent progress in the analysis of protein deamidation using mass spectrometry. Methods 2020; 200:42-57. [PMID: 32544593 DOI: 10.1016/j.ymeth.2020.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/15/2020] [Accepted: 06/11/2020] [Indexed: 02/06/2023] Open
Abstract
Deamidation is a nonenzymatic and spontaneous posttranslational modification (PTM) that introduces changes in both structure and charge of proteins, strongly associated with aging proteome instability and degenerative diseases. Deamidation is also a common PTM occurring in biopharmaceutical proteins, representing a major cause of degradation. Therefore, characterization of deamidation alongside its inter-related modifications, isomerization and racemization, is critically important to understand their roles in protein stability and diseases. Mass spectrometry (MS) has become an indispensable tool in site-specific identification of PTMs for proteomics and structural studies. In this review, we focus on the recent advances of MS analysis in protein deamidation. In particular, we provide an update on sample preparation, chromatographic separation, and MS technologies at multi-level scales, for accurate and reliable characterization of protein deamidation in both simple and complex biological samples, yielding important new insight on how deamidation together with isomerization and racemization occurs. These technological progresses will lead to a better understanding of how deamidation contributes to the pathology of aging and other degenerative diseases and the development of biopharmaceutical drugs.
Collapse
Affiliation(s)
- Yujia Ying
- School of Pharmaceutical Sciences, University of Sun Yat-sen University, No.132 Wai Huan Dong Lu, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; School of Pharmacy, China Pharmaceutical University, 639 Longmian Avenue, Nanjing 211198, China
| | - Huilin Li
- School of Pharmaceutical Sciences, University of Sun Yat-sen University, No.132 Wai Huan Dong Lu, Guangzhou Higher Education Mega Center, Guangzhou 510006, China; Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510006, China.
| |
Collapse
|
7
|
Fujii N, Takata T, Kim I, Morishima K, Inoue R, Magami K, Matsubara T, Sugiyama M, Koide T. Asp isomerization increases aggregation of α-crystallin and decreases its chaperone activity in human lens of various ages. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140446. [PMID: 32442520 DOI: 10.1016/j.bbapap.2020.140446] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 10/24/2022]
Abstract
α-Crystallin, comprising 40-50 subunits of αA- and αB-subunits, is a long-lived major soluble chaperone protein in lens. During aging, α-crystallin forms aggregates of high molecular weight (HMW) protein and eventually becomes water-insoluble (WI). Isomerization of Asp in α-crystallin has been proposed as a trigger of protein aggregation, ultimately leading to cataract formation. Here, we have investigated the relationship between protein aggregation and Asp isomerization of αA-crystallin by a series of analyses of the soluble α-crystallin, HMW and WI fractions from human lens samples of different ages (10-76 years). Analytical ultracentrifugation showed that the HMW fraction had a peak sedimentation coefficient of 40 S and a wide distribution of values (10-450 S) for lens of all ages, whereas the α-crystallin had a much smaller peak sedimentation coefficient (10-20 S) and was less heterogeneous, regardless of lens age. Measurement of the ratio of isomers (Lα-, Lβ-, Dα-, Dβ-) at Asp58, Asp91/92 and Asp151 in αA-crystallin by liquid chromatography-mass spectrometry showed that the proportion of isomers at all three sites increased in order of aggregation level (α-crystallin < HMW < WI fractions). Among the abnormal isomers of Asp58 and Asp151, Dβ-isomers were predominant with a very few exceptions. Notably, the chaperone activity of HMW protein was minimal for lens of all ages, whereas that of α-crystallin decreased with increasing lens age. Thus, abnormal aggregation caused by Asp isomerization might contribute to the loss of chaperone activity of α-crystallin in aged human lens.
Collapse
Affiliation(s)
- Noriko Fujii
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan.
| | - Takumi Takata
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Ingu Kim
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Ken Morishima
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Rintaro Inoue
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Kousuke Magami
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | | | - Masaaki Sugiyama
- Institute for Integrated Radiation and Nuclear Science, Kyoto University Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan
| | - Tamaki Koide
- Rexxam Co., Ltd., Nishi-ku, Nagoya, Aichi 541-0054, Japan
| |
Collapse
|
8
|
Takata T, Ha S, Koide T, Fujii N. Site-specific rapid deamidation and isomerization in human lens αA-crystallin in vitro. Protein Sci 2020; 29:955-965. [PMID: 31930615 PMCID: PMC7096717 DOI: 10.1002/pro.3821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 12/16/2022]
Abstract
Recent studies have suggested that the isomerization/racemization of aspartate residues in proteins increases in aged tissues. One such residue is Asp151 in lens-specific αA-crystallin. Although many isomerization/racemization sites have been reported in various proteins, the factors that lead to those modifications in proteins in vivo remain obscure. Therefore, an in vitro system is needed to assess the mechanisms of modifications of Asp under various conditions. Deamidation of Asn to Asp in proteins occurs more rapidly than isomerization/racemization of Asp, although the reaction passes through the same intermediate in both pathways. Here, therefore, we replaced Asp151 in human lens αA-crystallin with Asn by using site-directed mutagenesis. The recombinant protein was expressed in Escherichia coli and used to investigate the deamidation/isomerization/racemization of Asn151 after incubation at 50°C for various durations and under different pH. After incubation, the mutant αA-crystallin was subjected to enzymatic digestion followed by liquid chromatography-MS/MS to evaluate the ratio of modifications in Asn151-containing peptides. The Asp151Asn αA-crystallin mutant showed rapid deamidation to Asp with the formation of specific Asp isomers. In particular, deamidation increased greatly under basic conditions. By contrast, subunit-subunit interactions between αA-crystallin and αB-crystallin had little effect on the modification of Asn151. Our findings suggest that the Asp151Asn αA-crystallin mutant represents a good in vitro model protein to assess deamidation, isomerization, and the racemization intermediates. Furthermore, our in vitro results show a different trend from in vivo data, implying the presence of specific factors that induce racemization from L-Asp to D-Asp residues in vivo.
Collapse
Affiliation(s)
- Takumi Takata
- Kyoto University Institute for Integrated Radiation and Nuclear ScienceOsakaJapan
| | - Seongmin Ha
- Department of ChemistryGraduate School of Science, Kyoto UniversityKyotoJapan
| | | | - Noriko Fujii
- Kyoto University Institute for Integrated Radiation and Nuclear ScienceOsakaJapan
| |
Collapse
|