Biomedical subjects

Meng Wang

Publications and source records attributed to Meng Wang.

At least 19 recordsLinked to original sources

PubMed2026

Genome-wide identification of CHY zinc finger and RING finger (CHYR) genes in pepper and functional characterization of CaCHYR5 in response to Phytophthora capsici infection.

CHY zinc finger and RING finger (CHYR) proteins play crucial roles in the growth and development, as well as stress response. To date, no systematic or comprehensive analysis of the CHYR gene family has been performed in pepper (Capsicum annuum L.). In this study, we identified 8 CaCHYR genes (CaCHYR1-CaCHYR8), which were classified into 3 groups based on phylogenetic relationships. CaCHYR members within the same group exhibited similar distributions of conserved motifs and exon-intron structures. Chromosomal localization analysis showed that 8 CaCHYR genes were unevenly distributed on 6 chromosomes. Segmental duplication, rather than tandem duplication, was found to be the major contributor to the expansion of this gene family. CaCHYR genes feature a variety of cis-elements involved in developmental processes, phytohormone responses, and stress adaptation. Expression analysis based on RNA-seq data revealed that CaCHYR genes exhibited distinct spatial expression patterns across different tissues and in response to Phytophthora capsici infection (PCI), and quantitative real-time PCR (qRT-PCR) further confirmed that three of them (CaCHYR2, CaCHYR3, and CaCHYR5) exhibited altered expression under PCI. Furthermore, transient overexpression of CaCHYR5 in pepper leaves increased susceptibility to PCI, suggesting its potential negative regulatory role in pepper defense against P. capsici. Collectively, these findings reveal the expression patterns and regulatory functions of pepper CHYR genes in growth and development, laying a groundwork for breeding pepper cultivars tolerant to PCI.

Phytophthora capsici infection (PCI)↗

PubMed2026

Lactylation-related immune-metabolic dysregulation defines prognostic and therapeutic stratification in lung adenocarcinoma.

BACKGROUND: Lactylation links lactate metabolism with inflammatory signaling and immune regulation in tumors. However, its cellular distribution and translational value in lung adenocarcinoma (LUAD) remain unclear. METHODS: Single-cell RNA-sequencing datasets GSE189357 and GSE171145 were integrated to characterize lactylation-related activity, intercellular communication, and malignant epithelial cell states in LUAD. Single-cell-derived lactylation-related differentially expressed genes were mapped to TCGA-LUAD and multiple GEO cohorts. Univariate Cox regression and machine learning algorithms were used to construct a lactylation-related prognostic signature (LRPS). The associations of LRPS with prognosis, immunotherapy response, drug sensitivity, genomic alterations, immune infiltration, and inflammation- and metabolism-related pathways were evaluated. KRT7 was further validated using virtual knockout analysis, spatial transcriptomics, and in vitro and in vivo experiments. RESULTS: lactylation-related transcriptional activity showed heterogeneous distribution across LUAD cell populations and was associated with altered cell-cell communication. In malignant epithelial cells, LRTS-high and LRTS-low states exhibited distinct metabolic, inflammatory, and tumor-related pathway activities. LRPS showed stable prognostic performance in TCGA-LUAD and multiple GEO cohorts and remained an independent prognostic factor. Low LRPS was associated with greater potential benefit from immunotherapy, whereas different LRPS groups displayed distinct drug sensitivity, genomic alteration, and immune microenvironment patterns. KRT7 was highly expressed in LUAD and associated with poor prognosis. KRT7 knockdown suppressed LUAD cell proliferation, migration, invasion, colony formation, and tumor growth in vivo. CONCLUSIONS: This study identifies lactylation-related immune-metabolic dysregulation as a clinically relevant feature of LUAD and develops a single-cell-guided LRPS for prognosis and therapeutic stratification. KRT7 emerged as an LRPS-related functional candidate with experimentally supported roles in malignant LUAD phenotypes.

Immunotherapy↗

PubMed2026

Genome-Wide Characterization of the ZIP Transporter Family in Sea Island Cotton (Gossypium barbadense L.) and Expression Profiling Under Heavy Metal and Pathogen Stresses.

G. barbadense represents an indispensable germplasm resource for high-quality textile fiber and disease resistance; nevertheless, systematic information regarding its ZRT/IRT-like protein (ZIP) gene family remains limited. Here, a total of 46 GbZIP genes were identified across the G. barbadense genome. Comprehensive bioinformatic investigations revealed uneven chromosomal distribution and confirmed that segmental/whole-genome duplications, supplemented by localized tandem duplications, drove family expansion. Members clustered within the same phylogenetic clades shared conserved motif organization and gene architecture, while promoter regions harbored abundant cis-acting elements associated with phytohormone and stress signaling. Transcriptome profiling indicated distinct expression patterns across vegetative/reproductive tissues, fiber and ovule developmental stages, and diverse abiotic stress conditions (cold, hot, drought, and salt). Quantitative Real-Time PCR (qRT-PCR) further validated that several GbZIP candidates exhibited temporal expression variations upon exposure to cadmium toxicity, V. dahliae infection, and combined Cd-V. dahliae stress. Specifically, GbZIP13, GbZIP18, GbZIP27, and GbZIP36 displayed prominent broad-spectrum responses to all three stress conditions, whereas GbZIP16, GbZIP29, and GbZIP30 showed stress-specific regulatory divergence. Overall, this study aims to systematically analyze the evolutionary characteristics and expression patterns of the GbZIP family, and to specifically evaluate the response differences under Cd stress, V. dahliae stress, and combined stress, in order to identify potential key candidate genes.

Gossypium barbadense↗

PubMed2026

Hypertensive mt. tRNAIle4263A>G mutation orchestrates vascular senescence and apoptosis by activation of mitochondria-ER interplay.

The pathogenic mechanism underlying diseases caused by mitochondrial DNA (mtDNA) mutation, including hypertension, persists as an unresolved global challenge. Although mutation-induced mitochondrial defects have been well characterized, how these mito-perturbations are converted into critical intermediary signaling cascades and contribute to diseases remain unknown. Here, using human induced pluripotent stem cell (hiPSC)-derived vascular organoids (VOs) and vascular cells, the hypertensive mt. tRNAIle4263A > G mutation was identified to induce vascular senescence, apoptosis and vascular-specific dysfunction through mitochondria-endoplasmic reticulum (ER) interaction. For the first time, this study mapped the transcriptional reprogramming landscape of human VOs carrying this mutation. Through systematic screening and functional validation, ER stress was screened out, together with downstream mitochondria-associated ER membranes-mitochondrial Ca2+ overload resulting in vascular abnormality. Pathological reactive oxygen species (ROS) elevation, driven by tRNAIle destabilization and bioenergetic failure, acts as the primary instigator of maladaptive ER stress activation in this cascade. Pharmacological targeting of this axis-using mito-Tempol (a mitochondria-targeted ROS scavenger), Tauro Ursodeoxycholic Acid (an ER stress inhibitor), or RU265 (a highly-selective mitochondrial calcium uniporter inhibitor)-rescues vascular abnormality. This study highlights mt. tRNAIle4263A > G mutation orchestrates vascular pathology through ROS induced activation of inter-organelle communication, resolving a long-standing knowledge gap between mtDNA mutations and diseases and establishing therapeutic nexuses for mtDNA mutation-related cardiovascular diseases.

Hypertension↗

PubMed2026

Complete Genome Sequence of Atractylodes virus A, a Novel Carlavirus Infecting Atractylodes lancea.

Atractylodes lancea is an important medicinal crop, but viral diseases have become increasingly severe in recent years. Viruses in the genus Carlavirus are common plant pathogens that are primarily transmitted by aphids and can cause stunted growth and reduced yields in their host plants. In this study, a novel carlavirus, tentatively named Atractylodes virus A (AVA), was identified from A. lancea plants exhibiting virus-like symptoms. The full-length genome of AVA is 8,817 nt in length and contains six open reading frames, displaying the typical genomic organization of the genus Carlavirus. The replicase and CP exhibit 53.43% and 56.72% amino acid identity, respectively, with those of previously characterized carlaviruses, indicating that AVA represents a novel species in the genus Carlavirus. This study expands our understanding of viral diversity in A. lancea and provides a scientific foundation for the prevention and control of viral diseases as well as for resistance breeding.

Genome, Viral↗

PubMed2026

Excess folate elevates formaldehyde genotoxicity in cell lines but not in mice or humans.

Folate metabolites are chemically unstable: spontaneous decomposition releases formaldehyde, a genotoxin in blood stem cells and a human carcinogen. Despite this, folic acid consumption frequently exceeds the Recommended Dietary Allowance and is prescribed at high doses for patients with blood disorders. However, the impact of excess folate on endogenous formaldehyde genotoxicity in vivo has not been studied. We find that excess tetrahydrofolate (THF) treatment of cell lines elevates formaldehyde-DNA adducts and genotoxicity. To test this in vivo, we fed a high-folic acid diet (10-fold above standard) to mice with heightened sensitivity to formaldehyde: detoxification-impaired Adh5-/- mice, and Fanconi anemia DNA repair mutants Fanca-/- and Fancj-/-. In contrast to cell lines, elevated tissue THF was not associated with increased formaldehyde-DNA adducts nor blood stem cell attrition. Finally, in cancer patients, high-dose folic acid therapy elevated plasma folic acid but did not increase formaldehyde-DNA adducts in peripheral blood mononuclear cells. In conclusion, increased folate in vivo does not elevate endogenous formaldehyde genotoxicity in sensitized mouse models or humans.

Animals↗

PubMed2026

Spatially confined electrochemical strategy with DNA-assembled nanogaps for SNP detection.

Accurate detection of low-abundance single nucleotide polymorphisms (SNPs) against a large excess of homologous wild-type sequences requires both selective molecular recognition and effective transduction of small sequence differences into measurable signals. Here, we report a spatially confined electrochemical strategy that couples sequence-selective recognition with size-dependent mass-transport gating. DNA-hybridization-driven self-assembly of gold nanoparticles (AuNPs) forms a three-dimensional self-assembled electrode (3D-SAE) with a DNA-defined interparticle architecture. Competitive probes (SP/WP) convert single-base recognition into distinct molecular-size states: the SNP-associated pathway preferentially triggers a hybridization chain reaction (HCR), generating bulky AuNP-anchored HCR/methylene blue complexes (Au@HCR/MB) with reduced electrochemical accessibility through the porous 3D-SAE, whereas the wild-type pathway does not trigger HCR and maintains a high-current response from more readily accessible MB-containing species. Thus, sequence recognition is translated into a molecular-size difference and subsequently into an electrochemical signal through differential mass transport. Under buffer conditions, the platform achieved a statistically estimated detection limit of ∼0.47 fM and a quantitative range of 1 fM-100 pM. It discriminated a 0.1% mutant abundance in a fragmented genomic-DNA background. The downstream signal-transduction chemistry is enzyme-free and isothermal. This work establishes a mechanistical recognition-size-conversion-mass-transport-gating architecture for electrochemical nucleic acid analysis.

Polymorphism, Single Nucleotide↗

PubMed2026

Genome-wide DNA methylation analysis revealed epigenetic mechanism underlying end-stage renal disease.

End-stage renal disease (ESRD) remains a major clinical challenge with high morbidity and mortality, and its molecular mechanisms, particularly those shared among diverse primary kidney diseases during progression to ESRD, have not been studied. Here we conduct a large-scale two-stage epigenome-wide association study of ESRD in two independent cohorts consisting of 704 controls and 1031 ESRD cases. We identify 52 ESRD-associated differentially methylated CpG positions (ESRD DMPs) showing consistent association between the two cohorts and across diverse kidney diseases, implicating 144 candidate genes enriched in inflammatory and immune pathways. Five of the 52 DMPs are associated with ESRD complications, and seven with renal function decline in early-stage chronic kidney disease, demonstrating their potential as prognostic biomarkers for ESRD and its complications. Our findings highlight inflammation, immune dysregulation, and renal fibrosis as shared epigenetic drivers of ESRD progression, and identify biomarkers with potential utility for risk stratification and therapeutic intervention.

Humans↗

PubMed2026

ARISE: RNA-anchored shared-edge topology and hierarchical fusion for spatial multi-omics integration.

MOTIVATION: Spatial multi-omics technologies jointly profile transcriptomes, proteins and chromatin accessibility in situ, enabling integrative analysis of tissue organization across molecular layers. However, most existing graph-based integration methods rely on independently constructed modality-specific k-nearest-neighbor graphs. When auxiliary modalities are sparse or noisy, these graphs can become topologically discordant, propagate spurious edges, weaken cross-modal alignment, and reduce spatial domain resolution. RESULTS: We present Anchored RNA for Integrated Spatial Embedding (ARISE), an RNA expression anchored framework for spatial multi-omics integration. ARISE defines a shared-edge topology by intersecting RNA feature-similarity and spatial-proximity graphs, encodes auxiliary modalities on this common scaffold, and integrates them through inside-out hierarchical fusion. We further show theoretically that graph intersection minimizes false-positive edges within a broad class of k-of-r graph fusion rules, providing a principled basis for topology anchoring. Across various spatial multi-omics benchmarks spanning simulated and real datasets in bi-modal and tri-modal settings, ARISE improves spatial domain identification, cross-modal consistency, and preservation of tissue structure relative to existing methods. Furthermore, the learned representation supports biologically meaningful downstream analyses, including marker-based domain annotation, pathway enrichment, and cis-regulatory inference, indicating that ARISE yields a robust and interpretable framework for spatial multi-omics integration. AVAILABILITY AND IMPLEMENTATION: The source code is available at https://github.com/XiangxiangWang-code/ARISE. The archived version used in this study is available at https://doi.org/10.6084/m9.figshare.32686137.v2.

Multiomics↗

PubMed2026

A divide and conquer strategy for recapitulating whole genome 3D structure using Hi-C data.

The three dimensional (3D) spatial organization of the genome is closely linked to biological functions and can be captured by Hi-C assays through interrogating genome-wide chromatin interactions. Methodologies for inferring 3D structures from Hi-C data summarized as a two-dimensional (2D) contact matrix can be broadly placed within the paradigms of optimization-based and sampling-based. Many optimization-based methods are capable of constructing whole genome 3D structures but do not account for spatial dependency in the 2D data matrix nor cell heterogeneity in bulk Hi-C data, which provide an average over millions of cells. Sampling-based methods, on the other hand, are probabilistic model-based and can account for not only dependency, heterogeneity, but also other features inherent in Hi-C data, such as over-dispersion and sparsity. However, whole-genome 3D structure recapitulation is too computationally expensive for sampling-based methods, while chromosome-by-chromosome strategies for sampling-based methods ignore important information on inter-chromosomal contacts. To address these issues, we propose the truncated Random effect EXpression-cut and paste (tREX-cap) method, which applies the tREX model within a divide and conquer strategy. The resulting method inherits the good data-feature-cognizant properties of tREX and, in the meantime, can efficiently infer the whole genome 3D structure. We demonstrate the performance of tREX-cap through an extensive simulation study and analyses of a Hi-C lymphoblastoid dataset and a Hi-C IMR90 dataset.

Humans↗

PubMed2026

Exploring Causal Links Between 91 Circulating Inflammatory Proteins and Hashimoto's Thyroiditis: A Bidirectional Mendelian Randomization Study.

BACKGROUND: Increasing evidence has linked inflammation to Hashimoto's thyroiditis (HT) etiology. However, the causal role of circulating inflammatory proteins in HT remains uncertain. To investigate this, we conducted a bidirectional Mendelian randomization (MR) study. METHODS: Genetic data for 91 inflammatory proteins and HT were sourced from publicly available GWAS databases. The PhenoScanner database was then searched for pleiotropic SNPs associated with potential confounders. Inverse variance weighted (IVW) analysis was used as the primary analysis, simultaneously supplemented by five sensitivity analyses to strengthen the results. RESULTS: The results revealed that, after false discovery rate (FDR) correction, interleukin (IL)-12p40 was causally associated with increased risk of HT (OR [95% CI] = 1.295 [1.172, 1.431], p = 3.66 × 10-7, PFDR = 3.33×10-5). Conversely, none of the inflammatory proteins was a consequence of HT. CONCLUSION: This study suggests that IL-12p40 is probably one of the factors correlated with HT etiology, contributing to a better understanding of the pathogenesis of HT and underscoring the potential for therapeutic interventions targeting inflammatory proteins.

Humans↗

PubMed2006

Eicosapentaenoic acid modifies lipid composition in caveolae and induces translocation of endothelial nitric oxide synthase.

Endothelial nitric oxide synthase (eNOS) plays a crucial role in the regulation of a variety of cardiovascular functions. Many studies have shown that dietary n-3 polyunsaturated fatty acids (PUFAs) have beneficial effects on coronary atherosclerosis. However, the mechanisms of n-3 PUFAs regulation in eNOS activation remain unknown. In the present study we investigated the effects of eicosapentaenoic acid (EPA, 20:5 n-3) on subcellular distribution of eNOS and lipid composition of caveolae. We demonstrated for the first time that EPA treatment profoundly altered lipid composition and fatty acyl substitutions of phospholipids in caveolae. We found that caveolin-1 was solely located in caveolae fractions in control cells, and EPA treatment displaced caveolin-1 from caveolae. eNOS was detected in the caveolin-enriched fractions and noncaveolae fractions in control cells. EPA treatment induced the translocation of eNOS from caveolae fractions to soluble fractions. P-eNOS was also distributed in both fractions. After EPA treatment, the level of p-eNOS in each fraction was increased but the distribution of which was unaffected. Moreover, the results of immunofluorescence confirmed that EPA could redistribute caveolin-1 and eNOS in plasma membrane. eNOS activity in HUVEC cells was increased after EPA treatment, which was in a dose dependent manner. And incubation with 50 microM EPA had the maximum effect on eNOS activity. Our results suggested that eNOS translocation was paralleled by a stimulated capacity for NO production in the cells. We found that total Akt and p-Akt were primarily presented in heavy membranes in control cells, and the relative level of p-Akt increased but the distribution did not change after EPA treatment. The distribution of CaM was slightly changed after EPA treatment. Our results indicated that n-3 PUFAs profoundly altered caveolae microenvironment, thereby modifying location and function of proteins in caveolae. EPA-induced alterations of lipid and proteins in caveolae may be an important mechanism in the pathophysiologic process of atherosclerosis.

Blotting, Western↗

PubMed2006

Annotation and expression profile analysis of 2073 full-length cDNAs from stress-induced maize (Zea mays L.) seedlings.

Full-length cDNAs are very important for genome annotation and functional analysis of genes. The number of full-length cDNAs from maize (Zea mays L.) remains limited. Here we report the construction of a full-length enriched cDNA library from osmotically stressed maize seedlings by using the modified CAP trapper method. From this library, 2073 full-length cDNAs were collected and further analyzed by sequencing from both the 5'- and 3'-ends. A total of 1728 (83.4%) sequences did not match known maize mRNA and full-length cDNA sequences in the GenBank database and represent new full-length genes. After alignment of the 2073 full-length cDNAs with 448 maize BAC sequences, it was found that 84 full-length cDNAs could be mapped to the BACs. Of these, 43 genes (51.2%) have been correctly annotated from the BAC clones, 37 genes (44.0%) have been annotated with a different exon-intron structure from our cDNA, and four genes (4.76%) had no annotations in the TIGR database. Expression analysis of 2073 full-length maize cDNAs using a cDNA macroarray led to the identification of 79 genes upregulated by stress treatments and 329 downregulated genes. Of the 79 stress-inducible genes, 30 genes contain ABRE, DRE, MYB, MYC core sequences or other abiotic-responsive cis-acting elements in their promoters. These results suggest that these cis-acting elements and the corresponding transcription factors take part in plant responses to osmotic stress either cooperatively or independently. Additionally, the data suggest that an ethylene signaling pathway may be involved in the maize response to drought stress.

DNA, Complementary↗

PubMed2006

Exposure to a nutrition supplementation intervention in early childhood and risk factors for cardiovascular disease in adulthood: evidence from Guatemala.

To study the role of nutrition in the association of birth size and childhood growth with development of cardiovascular disease, the authors in 2002-2004 surveyed 665 men and 790 women aged 25-42 years who had been exposed as children to a community-randomized nutrition supplementation intervention in four villages in eastern Guatemala. Exposure was associated with a lower fasting glucose level (7.0 mg/dl, 95% confidence interval (CI): 0.5, 13.5) for exposure at ages 36-72 months; lower systolic blood pressure (3.0 mmHg, 95% CI: 0.4, 5.6) for exposure at ages 24-60 months; and a lower triglyceride level (sex-adjusted; 22.2 mg/dl, 95% CI: 0.4, 44.1) and higher high density lipoprotein cholesterol level (males only; 4.7 mg/dl, 95% CI: 1.5, 7.9) for exposure prior to age 36 months. Improved nutrition at any age prior to 7 years was not associated with diastolic blood pressure, total or low density lipoprotein cholesterol level, or prevalence of the metabolic syndrome. Interventions designed to address nutrient deficiencies and ameliorate stunting that are targeted at pregnant women and young children are unlikely to increase cardiovascular disease risk later in life and may instead lower the risk.

Adult↗

PubMed2006

Surface modification of phenolphthalein poly(ether sulfone) ultrafiltration membranes by blending with acrylonitrile-based copolymer containing ionic groups for imparting surface electrical properties.

Asymmetric ultrafiltration membranes were fabricated from the blends of phenolphthalein polyethersulfone (PES-C) and acrylonitrile copolymers containing charged groups, poly(acrylonitrile-co-acrylamido methylpropane sulfonic acid) (PAN-co-AMPS). From the surface analysis by XPS and ATR-FTIR, it was found that the charged groups tend to accumulate onto the membrane surface. This result indicated that membrane surface modification for imparting surface electrical properties could be carried out by blending charged polymer. Furthermore, with the help of a relatively novel method to measure membrane conduction, the true zeta potentials calculated on the basis of the streaming potential measurements were used to reflect the charge state of membrane surface. In addition, it was noteworthy that, from the profiles of zeta potential versus pH curves and the magnitude of zeta potentials, the determination of zeta potential was dependent not only on the electrical properties of membrane surface but also on its hydrophilicity. At last, based on a relatively elaborate study on the electrostatic interaction between the membrane surface and protein, it was found that these charged membranes could meet different demands of membrane applications, such as resisting protein fouling or protein separation, through adjusting solution pH value.

Journal Article↗

PubMed2006

Therapeutic potential of chitosan and its derivatives in regenerative medicine.

BACKGROUND: Cell-based transplantation, tissue engineering and gene therapy are important therapeutic strategies for present and future regenerative medicine. One challenge is to present the target cells in a suitable matrix to allow the cells to survive the wound contraction, tissue repair, and remodeling in certain tissues. Recently, functional biomaterial research has been directed towards the development of improved scaffolds and new drug delivery systems for regenerative medicine. MATERIALS AND METHODS: A literature survey was performed in basic and clinic publications relevant to the therapeutic potential of chitosan and its derivatives in regenerative medicine. In this review the functional properties and potential applications of chitosan and its derivatives in regenerative medicine are presented and discussed. RESULTS: Chitosan can be obtained by alkaline deacetylation of chitin and is found to be a natural-based nontoxic, biocompatible, and biodegradable polymer with anti-microbial activity. Chitosan and its derivatives could accelerate wound healing by enhancing the functions of inflammatory cells and repairing cells. Recent studies further indicated that chitosan and its derivatives also are novel scaffold materials for tissue engineering and are-promising non-viral vectors for gene delivery. CONCLUSIONS: Regenerative medicine has entered a new era with the development of modern science and technology. The novel properties of chitosan make it a versatile biomaterial for cell therapy, tissue engineering and gene therapy. It is hoped that these diverse approaches for regenerative medicine will translate from "bench to bedside" in the future.

Animals↗

PubMed2006

Analysis of amphetamine, methamphetamine and methylenedioxy-methamphetamine by micellar capillary electrophoresis using cation-selective exhaustive injection.

Cation-selective exhaustive injection (CSEI) is used as an on-line concentration method for the high-sensitivity analysis of illicit amphetamines using CE. Optimum conditions for the determination of amphetamine, methamphetamine and methylenedioxy-methamphetamine were investigated. Sodium dodecyl sulfate (25 mM) in 100 mM phosphate buffer (pH 2.9) with 20% methanol as organic additive was used as the background electrolyte for CE separation. The LOD, based on an S/N of 3:1, was about 0.01 microg/mL using normal capillary micellar electrokinetic chromatography, while by using CSEI in combination with micellar sweeping the sensitivity increased up to 1000-fold with the LOD lower than 50 pg/mL. The reproducibility of CSEI combined with micellar sweeping for analyzing amphetamines was satisfactory (relative standard deviation around 10% by using area ratios against an internal standard). This method is highly sensitive and can be used to analyze trace amount amphetamines in human hair.

Amphetamine↗

PubMed2006

Arginine 54 and Tyrosine 118 residues of {alpha}A-crystallin are crucial for lens formation and transparency.

PURPOSE: To identify new mouse models for studying roles of alphaAlpha-crystallin in vivo and to investigate why and how different mutations of the alphaAlpha-crystallin gene lead to dominant or recessive cataracts. METHODS: Using mouse genetic approaches and slit lamp screening, we identified two mouse cataractous mutant lines. Causative genes were mapped by a genome-wide linkage analysis. DNA sequencing verified missense mutations of alphaA-crystallin gene in both mutant lines. Histology, imaging of green fluorescent protein (GFP)-positive lenses, and protein 2-DE gel were used to determine the morphologic and biochemical properties of mutant lenses. RESULTS: Two new alphaA-crystallin gene mutations were identified, alphaA-R54C (alphaA-Cys) and alphaA-Y118D, which cause recessive whole cataracts and dominant nuclear cataracts, respectively. In homozygous alphaA-Cys mutant mice, lens epithelial and fiber cells lost their characteristic cellular features and developed disrupted subcellular structures, such as actin filaments and mitochondria. The nuclear cataract caused by alphaA-Y118D mutation was associated with increased water-insoluble crystallins (alpha, beta, and gamma classes). These results suggest that the Arg54 residue in the N-terminal region is crucial for alphaA-crystallin to perform its roles in lens epithelial and fiber cells during development, whereas the Y118D mutation in the central alpha-crystallin domain impairs alphaA-crystallin's ability to maintain the solubility of crystallin proteins in the lens. CONCLUSIONS: This work demonstrates that different regions of alphaA-crystallin mediate distinct functions in vivo. These two mutant mouse lines provide useful animal models for further investigating the multiple roles of alphaA-crystallin in the lens.

Actins↗