Submit to IJMS Review for IJMS Propose a Special Issue

Journal Menu

Journal Browser

Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0

Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Molecular Pathology, Diagnostics, and Therapeutics".

Deadline for manuscript submissions: closed (12 May 2022) | Viewed by 33681

Share This Special Issue

Special Issue Editor

Dr. Igor A. Butovich

E-Mail Website
Guest Editor

1. Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9057, USA
2. The Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390-9057, USA
Interests: analytical (bio)chemistry; biochemistry, physiology, and pathophysiology of the ocular surface; chemistry, biochemistry, and biophysics of lipids; chemistry, biochemistry, and biophysics of the tear film and meibum; drug discovery; enzymology; meibomian gland studies
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue is a continuation of our previous Special Issue "Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology" (https://www.mdpi.com/journal/ijms/special_issues/OMICS_eye).

This Special Issue of IJMS is seeking articles that would provide new insights into the molecular aspects of physiology and biochemistry of the eye and adnexa, from an OMICS point of view. Submissions with an emphasis on emerging approaches, such as genomics, metabolomics/metabonomis, proteomics, lipidomics, and glycomics are welcome. The Special Issue will aim to present a broad view of the ocular surface, conjunctiva, cornea, retina, eyelids, meibomian and lacrimal glands, and other ocular structures in the norm and pathology. The molecular bases of diseases are often poorly understood, and so are the effects of aging, gender, diet, pharmaceutical intervention, etc. Obtaining and discussing new information on the molecular mechanisms of these processes, and the molecular differences between metabolomes, proteomes, lipidomes, and glycomes of healthy tissues, organs, and secretions, and those of patients with ocular pathologies, would be an important step toward finding cures for those conditions.

Dr. Igor Butovich
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Eye
Meibomian Gland
Lacrimal Gland
Conjunctiva
Cornea
Retina
Ocular Surface
Metabolomics
Lipidomics
Proteomics
Genomics
Glycobiology

Published Papers (11 papers)

Download All Papers

Research

19 pages, 4484 KiB

Open AccessArticle

Dynamic Changes in the Gene Expression Patterns and Lipid Profiles in the Developing and Maturing Meibomian Glands

by Igor A. Butovich and Amber Wilkerson

Int. J. Mol. Sci. 2022, 23(14), 7884; https://doi.org/10.3390/ijms23147884 - 17 Jul 2022

Cited by 5 | Viewed by 1717

Abstract

Meibomian glands (MGs) and their holocrine secretion—meibum—play crucial roles in the physiology of the eye, providing protection from environmental factors and desiccation, among other functions. Importantly, aging was implicated in the deterioration of the morphology and functions of MGs, and the quantity and quality of meibum they produce, leading to a loss of its protective properties, while the meibum of young individuals and experimental animals provide ample protection to the eye. Currently, the molecular mechanisms of meibum biosynthesis (termed meibogenesis) are not fully understood. To characterize the physiological changes in developing and maturing MGs, we studied the lipidomes and transcriptomes of mouse MGs ranging from newborns to adults. The results revealed a gradual increase in the critical genes of meibogenesis (such as Elovl3, Elovl4, Awat2, and Soat1, among others) that positively correlated with the biosynthesis of their respective lipid products. The MG transcriptomes of young and adult mice were also analyzed using single-cell RNA sequencing. These experiments revealed the existence of multiple unique populations of MG cells (meibocytes, epithelial cells, and others) with specific combinations of genes that encode meibogenesis-related proteins, and identified clusters and subclusters of cells that were tentatively classified as meibocytes at different stages of differentiation/maturation, or their progenitor cells. A hypothesis was formulated that these cells may produce different types of lipids, and contribute differentially to the Meibomian lipidome. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

15 pages, 2610 KiB

Open AccessArticle

Comparison of Different Mass Spectrometry Workflows for the Proteomic Analysis of Tear Fluid

by Garrett Jones, Tae Jin Lee, Joshua Glass, Grace Rountree, Lane Ulrich, Amy Estes, Mary Sezer, Wenbo Zhi, Shruti Sharma and Ashok Sharma

Int. J. Mol. Sci. 2022, 23(4), 2307; https://doi.org/10.3390/ijms23042307 - 19 Feb 2022

Cited by 13 | Viewed by 4336

Abstract

The tear film is a multi-layer fluid that covers the corneal and conjunctival epithelia of the eye and provides lubrication, nutrients, and protection from the outside environment. Tear fluid contains a high concentration of proteins and has thus been recognized as a potential source of biomarkers for ocular disorders due to its proximity to disease sites on the ocular surface and the non-invasive nature of its collection. This is particularly true in the case of dry eye disease, which directly impacts the tear film and its components. Proteomic analysis of tear fluid is challenging mainly due to the wide dynamic range of proteins and the small sample volumes. However, recent advancements in mass spectrometry have revolutionized the field of proteomics enabling unprecedented depth, speed, and accuracy, even with small sample volumes. In this study using the Orbitrap Fusion Tribrid mass spectrometer, we compared four different mass spectrometry workflows for the proteomic analysis of tear fluid collected via Schirmer strips. We were able to establish a method of in-strip protein digestion that identified >3000 proteins in human tear samples from 11 healthy subjects. Our method offers a significant improvement in the number of proteins identified compared to previously reported methods without pooling samples. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

16 pages, 4482 KiB

Open AccessArticle

Sodium Iodate-Induced Degeneration Results in Local Complement Changes and Inflammatory Processes in Murine Retina

by Anne Enzbrenner, Rahel Zulliger, Josef Biber, Ana Maria Quintela Pousa, Nicole Schäfer, Corinne Stucki, Nicolas Giroud, Marco Berrera, Elod Kortvely, Roland Schmucki, Laura Badi, Antje Grosche, Diana Pauly and Volker Enzmann

Int. J. Mol. Sci. 2021, 22(17), 9218; https://doi.org/10.3390/ijms22179218 - 26 Aug 2021

Cited by 29 | Viewed by 5220

Abstract

Age-related macular degeneration (AMD), one of the leading causes of blindness worldwide, causes personal suffering and high socioeconomic costs. While there has been progress in the treatments for the neovascular form of AMD, no therapy is yet available for the more common dry form, also known as geographic atrophy. We analysed the retinal tissue in a mouse model of retinal degeneration caused by sodium iodate (NaIO₃)-induced retinal pigment epithelium (RPE) atrophy to understand the underlying pathology. RNA sequencing (RNA-seq), qRT-PCR, Western blot, immunohistochemistry of the retinas and multiplex ELISA of the mouse serum were applied to find the pathways involved in the degeneration. NaIO₃ caused patchy RPE loss and thinning of the photoreceptor layer. This was accompanied by the increased retinal expression of complement components c1s, c3, c4, cfb and cfh. C1s, C3, CFH and CFB were complement proteins, with enhanced deposition at day 3. C4 was upregulated in retinal degeneration at day 10. Consistently, the transcript levels of proinflammatory ccl-2, -3, -5, il-1β, il-33 and tgf-β were increased in the retinas of NaIO₃ mice, but vegf-a mRNA was reduced. Macrophages, microglia and gliotic Müller cells could be a cellular source for local retinal inflammatory changes in the NaIO₃ retina. Systemic complement and cytokines/chemokines remained unaltered in this model of NaIO₃-dependent retinal degeneration. In conclusion, systemically administered NaIO₃ promotes degenerative and inflammatory processes in the retina, which can mimic the hallmarks of geographic atrophy. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Graphical abstract

24 pages, 4082 KiB

Open AccessArticle

Differential Retinal Protein Expression in Primary and Secondary Retinal Ganglion Cell Degeneration Identified by Integrated SWATH and Target-Based Proteomics

by Jacky M. K. Kwong, Joseph Caprioli, Ying H. Sze, Feng J. Yu, King K. Li, Chi H. To and Thomas C. Lam

Int. J. Mol. Sci. 2021, 22(16), 8592; https://doi.org/10.3390/ijms22168592 - 10 Aug 2021

Cited by 4 | Viewed by 2594

Abstract

To investigate the retinal proteins associated with primary and secondary retinal ganglion cell (RGC) degeneration and explore their molecular pathways, SWATH label-free and target-based mass spectrometry was employed to identify the proteomes in various retinal locations in response to localized optic nerve injury. Unilateral partial optic nerve transection (pONT) was performed on adult Wistar rats and their retinas were harvested 2 weeks later. To confirm the separation of primary and secondary RGC degeneration, immunohistochemistry of RNA binding protein with multiple splicing (RBPMS) and glial fibrillary acidic protein (GFAP) was performed on retinal whole-mounts. Retinal proteomes in the temporal and nasal quadrants were evaluated with high resolution hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS), and SWATH-based acquisition, and their expression was compared to the corresponding retinal quadrant in contralateral control eyes and further validated by multiple reaction monitoring mass spectrometry (MRM-MS). A total of 3641 proteins (FDR < 1%) were identified using QTOF-MS. The raw data are available via ProteomeXchange with the identifier PXD026783. Bioinformatics data analysis showed that there were 37 upregulated and 25 downregulated proteins in the temporal quadrant, whereas 20 and five proteins were upregulated and downregulated, respectively, in the nasal quadrant, respectively (n = 4, p < 0.05; fold change ≥ 1.4-fold or ≤0.7). Six proteins were regulated in both the temporal and the nasal quadrants, including CLU, GFAP, GNG5, IRF2BPL, L1CAM, and CPLX1. Linear regression analysis indicated a strong association between the data obtained by means of SWATH-MS and MRM-MS (temporal, R² = 0.97; nasal, R² = 0.96). Gene ontology analysis revealed statistically significant changes in the biological processes and cellular components of primary RGC degeneration. The majority of the significant changes in structural, signaling, and cell death proteins were associated with the loss of RGCs in the area of primary RGC degeneration. The combined use of SWATH-MS and MRM-MS methods detects and quantifies regional changes of retinal protein expressions after localized injury. Future investigation with this integrated approach will significantly increase the understanding of diverse processes of progressive RGC degeneration from a proteomic prospective. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

12 pages, 2216 KiB

Open AccessArticle

UV Effect on Human Anterior Lens Capsule Macro-Molecular Composition Studied by Synchrotron-Based FTIR Micro-Spectroscopy

by Xhevat Lumi, Tanja Dučić, Martin Kreuzer, Marko Hawlina and Sofija Andjelic

Int. J. Mol. Sci. 2021, 22(10), 5249; https://doi.org/10.3390/ijms22105249 - 16 May 2021

Cited by 6 | Viewed by 2015

Abstract

Ultraviolet (UV) irradiation is an important risk factor in cataractogenesis. Lens epithelial cells (LECs), which are a highly metabolically active part of the lens, play an important role in UV-induced cataractogenesis. The purpose of this study was to characterize cell compounds such as nucleic acids, proteins, and lipids in human UV C-irradiated anterior lens capsules (LCs) with LECs, as well as to compare them with the control, non-irradiated LCs of patients without cataract, by using synchrotron radiation-based Fourier transform infrared (SR-FTIR) micro-spectroscopy. In order to understand the effect of the UV C on the LC bio-macromolecules in a context of cataractogenesis, we used the SR-FTIR micro-spectroscopy setup installed on the beamline MIRAS at the Spanish synchrotron light source ALBA, where measurements were set to achieve a single-cell resolution with high spectral stability and high photon flux. UV C irradiation of LCs resulted in a significant effect on protein conformation with protein formation of intramolecular parallel β-sheet structure, lower phosphate and carboxyl bands in fatty acids and amino acids, and oxidative stress markers with significant increase of lipid peroxidation and diminishment of the asymmetric CH₃ band. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

28 pages, 4102 KiB

Open AccessArticle

SWATH Based Quantitative Proteomics Reveals Significant Lipid Metabolism in Early Myopic Guinea Pig Retina

by Jingfang Bian, Ying-Hon Sze, Dennis Yan-Yin Tse, Chi-Ho To, Sally A. McFadden, Carly Siu-Yin Lam, King-Kit Li and Thomas Chuen Lam

Int. J. Mol. Sci. 2021, 22(9), 4721; https://doi.org/10.3390/ijms22094721 - 29 Apr 2021

Cited by 17 | Viewed by 3387

Abstract

Most of the previous myopic animal studies employed a single-candidate approach and lower resolution proteomics approaches that were difficult to detect minor changes, and generated limited systems-wide biological information. Hence, a complete picture of molecular events in the retina involving myopic development is lacking. Here, to investigate comprehensive retinal protein alternations and underlying molecular events in the early myopic stage, we performed a data-independent Sequential Window Acquisition of all Theoretical Mass Spectra (SWATH) based proteomic analysis coupled with different bioinformatics tools in pigmented guinea pigs after 4-day lens-induced myopia (LIM). Myopic eyes compared to untreated contralateral control eyes caused significant changes in refractive error and choroid thickness (p < 0.05, n = 5). Relative elongation of axial length and the vitreous chamber depth were also observed. Using pooled samples from all individuals (n = 10) to build a species-specific retinal ion library for SWATH analysis, 3202 non-redundant proteins (with 24,616 peptides) were identified at 1% global FDR. For quantitative analysis, the 10 individual retinal samples (5 pairs) were analyzed using a high resolution Triple-TOF 6600 mass spectrometry (MS) with technical replicates. In total, 37 up-regulated and 21 down-regulated proteins were found significantly changed after LIM treatment (log2 ratio (T/C) > 0.26 or < −0.26; p ≤ 0.05). Data are accepted via ProteomeXchange with identifier PXD025003. Through Ingenuity Pathways Analysis (IPA), “lipid metabolism” was found as the top function associated with the differentially expressed proteins. Based on the protein abundance and peptide sequences, expression patterns of two regulated proteins (SLC6A6 and PTGES2) identified in this pathway were further successfully validated with high confidence (p < 0.05) using a novel Multiple Reaction Monitoring (MRM) assay on a QTRAP 6500+ MS. In summary, through an integrated discovery and targeted proteomic approach, this study serves as the first report to detect and confirm novel retinal protein changes and significant biological functions in the early LIM mammalian guinea pigs. The study provides new workflow and insights for further research to myopia control. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

15 pages, 4068 KiB

Open AccessArticle

Depletion of Cholesteryl Esters Causes Meibomian Gland Dysfunction-Like Symptoms in a Soat1-Null Mouse Model

by Igor A. Butovich, Amber Wilkerson and Seher Yuksel

Int. J. Mol. Sci. 2021, 22(4), 1583; https://doi.org/10.3390/ijms22041583 - 04 Feb 2021

Cited by 17 | Viewed by 2807

Abstract

Previous studies on ablation of several key genes of meibogenesis related to fatty acid elongation, omega oxidation, and esterification into wax esters have demonstrated that inactivation of any of them led to predicted changes in the meibum lipid profiles and caused severe abnormalities in the ocular surface and Meibomian gland (MG) physiology and morphology. In this study, we evaluated the effects of Soat1 ablation that were expected to cause depletion of the second largest class of Meibomian lipids (ML)—cholesteryl esters (CE)—in a mouse model. ML of the Soat1-null mice were examined using liquid chromatography high-resolution mass spectrometry and compared with those of Soat1^+/− and wild-type mice. Complete suppression of CE biosynthesis and simultaneous accumulation of free cholesterol (Chl) were observed in Soat1-null mice, while Soat1^+/− mutants had normal Chl and CE profiles. The total arrest of the CE biosynthesis in response to Soat1 ablation transformed Chl into the dominant lipid in meibum accounting for at least 30% of all ML. The Soat1-null mice had clear manifestations of dry eye and MG dysfunction. Enrichment of meibum with Chl and depletion of CE caused plugging of MG orifices, increased meibum rigidity and melting temperature, and led to a massive accumulation of lipid deposits around the eyes of Soat1-null mice. These findings illustrate the role of Soat1/SOAT1 in the lipid homeostasis and pathophysiology of MG. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

17 pages, 11952 KiB

Open AccessArticle

Tear Proteomics Study of Dry Eye Disease: Which Eye Do You Adopt as the Representative Eye for the Study?

by Ming-Tse Kuo, Po-Chiung Fang, Shu-Fang Kuo, Alexander Chen and Yu-Ting Huang

Int. J. Mol. Sci. 2021, 22(1), 422; https://doi.org/10.3390/ijms22010422 - 03 Jan 2021

Cited by 9 | Viewed by 3184

Abstract

Most studies about dry eye disease (DED) chose unilateral eye for investigation and drew conclusions based on monocular results, whereas most studies involving tear proteomics were based on the results of pooling tears from a group of DED patients. Patients with DED were consecutively enrolled for binocular clinical tests, tear biochemical markers of DED, and tear proteome. We found that bilateral eyes of DED patients may have similar but different ocular surface performance and tear proteome. Most ocular surface homeostatic markers and tear biomarkers were not significantly different in the bilateral eyes of DED subjects, and most clinical parameters and tear biomarkers were correlated significantly between bilateral eyes. However, discrepant binocular presentation in the markers of ocular surface homeostasis and the associations with tear proteins suggested that one eye’s performance cannot represent that of the other eye or both eyes. Therefore, in studies for elucidating tear film homeostasis of DED, we may lose some important messages hidden in the fellow eye if we collected clinical and proteomic data only from a unilateral eye. For mechanistic studies, it is recommended that researchers collect tear samples from the eye with more severe DED under sensitive criteria for identifying the more severe eye and evaluating the tear biochemical and proteomic markers with binocular concordance drawn in prior binocular studies. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

20 pages, 5663 KiB

Open AccessArticle

Obese Mice with Dyslipidemia Exhibit Meibomian Gland Hypertrophy and Alterations in Meibum Composition and Aqueous Tear Production

by Eugene A. Osae, Tiffany Bullock, Madhavi Chintapalati, Susanne Brodesser, Samuel Hanlon, Rachel Redfern, Philipp Steven, C. Wayne Smith, Rolando E. Rumbaut and Alan R. Burns

Int. J. Mol. Sci. 2020, 21(22), 8772; https://doi.org/10.3390/ijms21228772 - 20 Nov 2020

Cited by 21 | Viewed by 2717

Abstract

Background: Dyslipidemia may be linked to meibomian gland dysfunction (MGD) and altered meibum lipid composition. The purpose was to determine if plasma and meibum cholesteryl esters (CE), triglycerides (TG), ceramides (Cer) and sphingomyelins (SM) change in a mouse model of diet-induced obesity where mice develop dyslipidemia. Methods: Male C57/BL6 mice (8/group, age = 6 wks) were fed a normal (ND; 15% kcal fat) or an obesogenic high-fat diet (HFD; 42% kcal fat) for 10 wks. Tear production was measured and meibography was performed. Body and epididymal adipose tissue (eAT) weights were determined. Nano-ESI-MS/MS and LC-ESI-MS/MS were used to detect CE, TG, Cer and SM species. Data were analyzed by principal component analysis, Pearson’s correlation and unpaired t-tests adjusted for multiple comparisons; significance set at p ≤ 0.05. Results: Compared to ND mice, HFD mice gained more weight and showed heavier eAT and dyslipidemia with higher levels of plasma CE, TG, Cer and SM. HFD mice had hypertrophic meibomian glands, increased levels of lipid species acylated by saturated fatty acids in plasma and meibum and excessive tear production. Conclusions: The majority of meibum lipid species with saturated fatty acids increased with HFD feeding with evidence of meibomian gland hypertrophy and excessive tearing. The dyslipidemia is associated with altered meibum composition, a key feature of MGD. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

16 pages, 3288 KiB

Open AccessArticle

A Genomic Approach to Investigating Ocular Surface Microorganisms: Monitoring Core Microbiota on Eyelid Margin with a Dot hybridization Assay

by Ming-Tse Kuo, Tsai-Ling Chao, Shu-Fang Kuo, Chun-Chih Chien, Alexander Chen, Yu-Hsuan Lai and Yu-Ting Huang

Int. J. Mol. Sci. 2020, 21(21), 8299; https://doi.org/10.3390/ijms21218299 - 05 Nov 2020

Cited by 5 | Viewed by 1917

Abstract

A sound ocular surface microbiota has been recognized as a part of ocular surface health following a growing body of evidence from next-generation sequencing technique and metagenomic analysis. However, even from the perspective of contemporary precision medicine, it is difficult to directly apply these new technologies to clinical practice. Therefore, we proposed a model based on dot hybridization assay (DHA) to bridge conventional culture with a metagenomic approach in investigating and monitoring ocular surface microbiota. Endophthalmitis, mostly caused by bacterial infection, is the most severe complication of many intraocular surgeries, such as cataract surgery. Hazardous microorganisms hiding and proliferating in the ocular surface microbiota not only increase the risk of endophthalmitis but also jeopardize the effectiveness of the preoperative aseptic procedure and postoperative topical antibiotics. The DHA model enables the simultaneous assessment of bacterial bioburden, detection of target pathogens and microorganisms, and surveillance of methicillin/oxacillin resistance gene mecA in the ocular surface microbiota. This assay revealed heavier bacterial bioburden in men, compatible with a higher risk of endophthalmitis in male patients who underwent cataract surgery. No occurrence of endophthalmitis for these patients was compatible with non-hazardous microorganisms identified by specific dots for target pathogens. Moreover, the mecA dot detected oxacillin-resistant strains, of which culture failed to isolate. Therefore, the DHA model could provide an alternative genomic approach to investigate and monitor ocular surface microorganisms in clinical practice nowadays. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Figure 1

18 pages, 2468 KiB

Open AccessArticle

Cataract-Associated New Mutants S175G/H181Q of βΒ2-Crystallin and P24S/S31G of γD-Crystallin Are Involved in Protein Aggregation by Structural Changes

by In-Kang Song, Seungjin Na, Eunok Paek and Kong-Joo Lee

Int. J. Mol. Sci. 2020, 21(18), 6504; https://doi.org/10.3390/ijms21186504 - 05 Sep 2020

Cited by 3 | Viewed by 2303

Abstract

β/γ-Crystallins, the main structural protein in human lenses, have highly stable structure for keeping the lens transparent. Their mutations have been linked to cataracts. In this study, we identified 10 new mutations of β/γ-crystallins in lens proteomic dataset of cataract patients using bioinformatics tools. Of these, two double mutants, S175G/H181Q of βΒ2-crystallin and P24S/S31G of γD-crystallin, were found mutations occurred in the largest loop linking the distant β-sheets in the Greek key motif. We selected these double mutants for identifying the properties of these mutations, employing biochemical assay, the identification of protein modifications with nanoUPLC-ESI-TOF tandem MS and examining their structural dynamics with hydrogen/deuterium exchange-mass spectrometry (HDX-MS). We found that both double mutations decrease protein stability and induce the aggregation of β/γ-crystallin, possibly causing cataracts. This finding suggests that both the double mutants can serve as biomarkers of cataracts. Full article

(This article belongs to the Special Issue Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Emerging OMICS Approaches to Studying the Eye in the Norm and Pathology 2.0

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (11 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI