Developmental analysis of the eye lens obsolescence (Elo) gene in the mouse: cell proliferation and Elo gene expression in the aggregation chimera

Development ◽  
1991 ◽  
Vol 113 (4) ◽  
pp. 1293-1304 ◽  
Author(s):  
A. Yoshiki ◽  
M. Hanazono ◽  
S. Oda ◽  
N. Wakasugi ◽  
T. Sakakura ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Epithelial Cells ◽  
Cell Number ◽  
S Phase ◽  
Lens Epithelium ◽  
Posterior Region ◽  
Lens Epithelial Cells ◽  
Eye Lens ◽  
Lens Fiber ◽  
Fiber Cells

This study investigates the primary effect of the eye lens obsolescence (Elo) gene of the mouse. Morphological features of the Elo lens were defined as follows: (1) deficient elongation of lens fiber cells, (2) morphological abnormality of nuclei of lens fiber cells, (3) lack of eosinophilic granules in the central fiber cells and (4) rupture of lens capsule in the posterior region. We have immunohistologically examined, by means of an in vivo BrdU incorporation system, whether or not the Elo gene regulates cell proliferation during lens development. The lens fiber cells were morphologically abnormal in day 13 embryonic Elo lens. However, there were no significant differences in morphology or cell proliferation between normal and Elo lens epithelium until day 14 of gestation. After day 15, the total cell number in the Elo lens epithelium was significantly less than that in the normal, but the total numbers of S-phase cells in the two genotypes were not significantly different. The ratio of the total S-phase cell number to the total number of lens epithelial cells may be affected by the developmental stage, but not directly by the genotype. The genotype, however, may be having a direct influence at later ages because malformation of Elo lens fiber cells must cause reduction of the total number of lens epithelial cells in older embryos. Although, at 30 days old, Elo lens cells were externally extruded through the ruptured capsule into the vitreous cavity, BrdU-labelled lens epithelial cells were detectable. To investigate whether the Elo lens phenotype is determined by its own genotype or by its cellular environment, we produced aggregation chimeras between C3H-Elo/+(C/C) and BALB/c(c/c). Most lenses of BALB/c dominant chimeras were oval in shape without the ruptured lens capsule. However, they were opaque in the center and slightly smaller in size than normal. The lenses of C3H-Elo/+ dominant chimeras were morphologically similar to the Elo lens. Although normal nuclei were regularly arranged in the anterior region, Elo-type nuclei were located in the posterior region. Immunohistological staining by using anti-C3H strain-specific antibody demonstrated that the lens fiber cells with abnormal nuclei were derived only from C3H-Elo/+, not from BALB/c. These observations suggest that the primary effect of the Elo gene in the developing lens may be specific to the fiber cell differentiation rather than to the cell proliferation.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals The Notch Signaling Pathway Controls the Size of the Ocular Lens by Directly Suppressing p57Kip2 Expression

2007 ◽  
Vol 27 (20) ◽  
pp. 7236-7247 ◽  
Author(s):  
Junling Jia ◽  
Min Lin ◽  
Lingna Zhang ◽  
J. Philippe York ◽  
Pumin Zhang
Keyword(s):  
Epithelial Cells ◽  
Notch Signaling ◽  
Signaling Pathway ◽  
Cell Cycle Control ◽  
Notch Signaling Pathway ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Ocular Lens ◽  
Fiber Cells ◽  
Proliferation And Differentiation

ABSTRACT The size of an organ must be tightly controlled so that it fits within an organism. The mammalian lens is a relatively simple organ composed of terminally differentiated, amitotic lens fiber cells capped on the anterior surface by a layer of immature, mitotic epithelial cells. The proliferation of lens epithelial cells fuels the growth of the lens, thus controling the size of the lens. We report that the Notch signaling pathway defines the boundary between proliferation and differentiation in the developing lens. The loss of Notch signaling results in the loss of epithelial cells to differentiation and a much smaller lens. We found that the Notch effector Herp2 is expressed in lens epithelium and directly suppresses p57 Kip2 expression, providing a molecular link between Notch signaling and the cell cycle control machinery during lens development.

Exposure to subthreshold dose of UVR-B induces apoptosis in the lens epithelial cells and does not in the lens fiber cells

2016 ◽  
Vol 94 ◽  
Author(s):  
K. Galichanin ◽  
Z. Yu ◽  
N. Talebizadeh ◽  
M. Burmakin ◽  
P. Söderberg
Keyword(s):  
Epithelial Cells ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Fiber Cells

Volume regulation in lens epithelial cells and differentiating lens fiber cells

1990 ◽  
Vol 143 (3) ◽  
pp. 455-459 ◽  
Author(s):  
David C. Beebe ◽  
Judith T. Parmelee ◽  
Karla S. Belcher
Keyword(s):  
Epithelial Cells ◽  
Volume Regulation ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Fiber Cells

scholarly journals Immunohistochemical and Chemical Changes of .BETA.-Citryl-L-glutamate in the Differentiation of Bovine Lens Epithelial Cells into Lens Fiber Cells.

2000 ◽  
Vol 23 (6) ◽  
pp. 704-707 ◽  
Author(s):  
Masanori NARAHARA ◽  
Keiichirou TACHIBANA ◽  
Narumi KURISU ◽  
Michiko KANAZAWA ◽  
Masaharu MIYAKE
Keyword(s):  
Epithelial Cells ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Chemical Changes ◽  
Fiber Cells ◽  
Bovine Lens

Calmodulin-mediated gating of lens gap junction channels in vesicles

1984 ◽  
Vol 42 ◽  
pp. 134-137
Author(s):  
Camillo Peracchia ◽  
Stephen J. Girsch
Keyword(s):  
Gap Junctions ◽  
Freeze Fracture ◽  
Orthogonal Arrays ◽  
Eye Lens ◽  
Lens Fiber ◽  
Cell Coupling ◽  
Particle Spacing ◽  
Fiber Cells ◽  
Gap Junction Channels ◽  
Communicating Junctions

The fiber cells of eye lens communicate directly with each other by exchanging ions, dyes and metabolites. In most tissues this type of communication (cell coupling) is mediated by gap junctions. In the lens, the fiber cells are extensively interconnected by junctions. However, lens junctions, although morphologically similar to gap junctions, differ from them in a number of structural, biochemical and immunological features. Like gap junctions, lens junctions are regions of close cell-to-cell apposition. Unlike gap junctions, however, the extracellular gap is apparently absent in lens junctions, such that their thickness is approximately 2 nm smaller than that of typical gap junctions (Fig. 1,c). In freeze-fracture replicas, the particles of control lens junctions are more loosely packed than those of typical gap junctions (Fig. 1,a) and crystallize, when exposed to uncoupling agents such as Ca++, or H+, into pseudo-hexagonal, rhombic (Fig. 1,b) and orthogonal arrays with a particle-to-particle spacing of 6.5 nm. Because of these differences, questions have been raised about the interpretation of the lens junctions as communicating junctions, in spite of the fact that they are the only junctions interlinking lens fiber cells.

Contrasting patterns of c-myc and N-myc expression in proliferating, quiescent, and differentiating cells of the embryonic chicken lens

Development ◽  
1992 ◽  
Vol 115 (3) ◽  
pp. 813-820
Author(s):  
L.L. Harris ◽  
J.C. Talian ◽  
P.S. Zelenka
Keyword(s):  
Cell Proliferation ◽  
Protein Product ◽  
Mrna Levels ◽  
Lens Fiber ◽  
Proliferating Cells ◽  
Fiber Cells ◽  
Embryonic Chicken ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation

The present study uses the polymerase chain reaction and in situ hybridization to examine c-myc and N-myc mRNA in the embryonic chicken lens at 6, 10, 14 and 19 days of development and compares the pattern of expression obtained with the developmental pattern of cell proliferation and differentiation. In the central epithelium, c-myc mRNA levels were proportional to the percentage of proliferating cells throughout development. N-myc mRNA expression in this region was relatively low and showed no correlation with cell proliferation. The ratio of N-myc to c-myc mRNA increased markedly with the onset of epithelial cell elongation and terminal fiber cell differentiation, although both c-myc and N-myc mRNAs continued to be expressed in postmitotic, elongating cells of the equatorial epithelium and in terminally differentiating lens fiber cells. Thus, increased expression of N-myc, a gene whose protein product may compete with c-myc protein for dimerization partners, accompanies the dissociation of c-myc expression and cell proliferation during terminal differentiation of lens fiber cells.

scholarly journals The effects of c-Src kinase on EMT signaling pathway in human lens epithelial cells associated with lens diseases

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Xingyu Li ◽  
Fang Wang ◽  
Meixia Ren ◽  
Minjuan Du ◽  
Jian Zhou
Keyword(s):  
Cell Proliferation ◽  
Epithelial Cells ◽  
Western Blot ◽  
Src Kinase ◽  
Human Lens ◽  
Lens Epithelial Cells ◽  
Protein Levels ◽  
Human Lens Epithelial Cells ◽  
And Migration ◽  
E Cadherin

Abstract Background The signaling pathway of epithelial to mesenchymal transition (EMT) is regulated by c-Src kinase in many cells. The purpose of this study was to investigate the effects of c-Src kinase on EMT of human lens epithelial cells in vivo stimulated by different factors. Methods Human lens epithelial cells, HLE-B3, were exposed to either an inflammatory factor, specifically IL-1α, IL-6, TNF-α or IL-1β, at 10 ng/mL or high glucose (35.5 mM) for 30 mins. Activity of c-Src kinase was evaluated by the expression of p-Src418 with western blot assay. To investigate the effects of activation of c-Src on EMT, HLE-B3 cells were transfected with pCDNA3.1-SrcY530F to upregulate activity of c-Src kinase, and pSlience4.1-ShSrc to knock it down. The expressions of c-Src kinase and molecular markers of EMT such as E-cadherin, ZO-1, α-SMA, and Vimentin were examined at 48 h by RT-PCR and western blot. At 48 h and 72 h of transfection, cell proliferation was detected by MTT, and cell mobility and migration were determined by scratch and transwell assays. Results Activity of c-Src kinase, which causes the expression of p-Src418, was upregulated by different inflammatory factors and high glucose in HLE-B3 cells. When HLE-B3 cells were transfected with pCDNA3.1-SrcY530F, the expression of c-Src kinase was upregulated on both mRNA and protein levels, and activity of c-Src kinase, expression of p-Src418 increased. The expressions of both E-cadherin and ZO-1 were suppressed, while the expressions of vimentin and α-SMA were elevated on both mRNA and protein levels at the same time. Cell proliferation, mobility and migration increased along with activation of c-Src kinase. Conversely, when HLE-B3 cells were transfected with pSlience4.1-ShSrc, both c-Src kinase and p-Src418 expressions were knocked down. The expressions of E-cadherin and ZO-1 increased, but the expressions of Vimentin and α-SMA decreased; meanwhile, cell proliferation, mobility and migration reduced. Conclusions The c-Src kinase in lens epithelial cells is easily activated by external stimuli, resulting in the induction of cell proliferation, mobility, migration and EMT.

scholarly journals Identification of Differential Gene Expression Pattern in Lens Epithelial Cells Derived from Cataractous and Noncataractous Lenses of Shumiya Cataract Rat

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Hidetoshi Ishida ◽  
Teppei Shibata ◽  
Yuka Nakamura ◽  
Yasuhito Ishigaki ◽  
Dhirendra P. Singh ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Expression Patterns ◽  
Synergetic Effect ◽  
Gene Expression Pattern ◽  
Lens Opacity ◽  
Lens Epithelial Cells ◽  
Lens Fiber ◽  
Molecular Events ◽  
Old Rats

The Shumiya cataract rat (SCR) is a model for hereditary cataract. Two-thirds of these rats develop lens opacity within 10-11 weeks. Onset of cataract is attributed to the synergetic effect of lanosterol synthase (Lss) and farnesyl-diphosphate farnesyltransferase 1 (Fdft1) mutant alleles that lead to cholesterol deficiency in the lenses, which in turn adversely affects lens biology including the growth and differentiation of lens epithelial cells (LECs). Nevertheless, the molecular events and changes in gene expression associated with the onset of lens opacity in SCR are poorly understood. In the present study, a microarray-based approach was employed to analyze comparative gene expression changes in LECs isolated from the precataractous and cataractous stages of lenses of 5-week-old SCRs. The changes in gene expression observed in microarray results in the LECs were further validated using real-time reverse transcribed quantitative PCR (RT-qPCR) in 5-, 8-, and 10-week-old SCRs. A mild posterior and cortical opacity was observed in 5-week-old rats. Expressions of approximately 100 genes, including the major intrinsic protein of the lens fiber (Mip and Aquaporin 0), deoxyribonuclease II beta (Dnase2B), heat shock protein B1 (HspB1), and crystallin γ (γCry) B, C, and F, were found to be significantly downregulated (0.07-0.5-fold) in rat LECs derived from cataract lenses compared to that in noncataractous lenses (control). Thus, our study was aimed at identifying the gene expression patterns during cataract formation in SCRs, which may be responsible for cataractogenesis in SCR. We proposed that cataracts in SCR are associated with reduced expression of these lens genes that have been reported to be related with lens fiber differentiation. Our findings may have wider implications in understanding the effect of cholesterol deficiency and the role of cholesterol-lowering therapeutics on cataractogenesis.

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