Limits...
Disruption of eyelid and cornea morphogenesis by epithelial β-catenin gain-of-function.

Mizoguchi S, Suzuki K, Zhang J, Yamanaka O, Liu CY, Okada Y, Miyajima M, Kokado M, Kao WW, Yamada G, Saika S - Mol. Vis. (2015)

Bottom Line: The ultrastructure of the ocular tissues of the E18.5 embryos was also examined.The mutant stroma exhibited impaired keratocyte differentiation with accelerated cell proliferation and reduction in the accumulation of collagen type I.The mutant embryos also showed hyperproliferative nodules in the ocular surface epithelia with anomaly of cornea-type epithelial differentiation and the absence of the epithelial basement membrane.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Wakayama Medical University School of Medicine, Wakayama, Japan.

ABSTRACT

Purpose: To examine the developmental pathobiology of the eyelid and the cornea caused by epithelial β-catenin gain-of-function (gof) during mouse embryogenesis.

Methods: Compound mutant mice (Ctnnb1(GOFOSE) , gof of β-catenin in the epidermis and the ocular surface epithelium) were generated by time-mating keratin 5-promoter-Cre recombinase (Krt5-Cre) and Ctnnb1(fE3/WT) (floxed exon 3 of Ctnnb1) mice. Eyes obtained from wild-type (WT) and mutant embryos at various gestation stages until E18.5 were examined with histology and immunohistochemistry. The ultrastructure of the ocular tissues of the E18.5 embryos was also examined.

Results: Expression of the gof-β-catenin mutant protein in the epidermis severely impaired eyelid morphogenesis at E15.5, E17.5, and E18.5. The mutant stroma exhibited impaired keratocyte differentiation with accelerated cell proliferation and reduction in the accumulation of collagen type I. The mutant embryos also showed hyperproliferative nodules in the ocular surface epithelia with anomaly of cornea-type epithelial differentiation and the absence of the epithelial basement membrane.

Conclusions: Expression of the gof-β-catenin mutant protein in basal epithelial cells disrupts eyelid and cornea morphogenesis during mouse embryonic development due to the perturbation of cell proliferation and differentiation of the epithelium and the neural crest-derived mesenchyme.

No MeSH data available.


Related in: MedlinePlus

Ultrastructure of the posterior corneal stroma of WT and mutant embryos at E18.5. A: Lamellar structure of piled elongated keratocytes and collagenous connective tissue are observed in the posterior stroma of the wild-type (WT) embryo cornea. B: This lamellar structure is not observed in the anterior stroma of the mutant cornea (asterisk). Neovascularization (NV) is also seen in the mutant stroma. Bar, 5 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4522241&req=5

f8: Ultrastructure of the posterior corneal stroma of WT and mutant embryos at E18.5. A: Lamellar structure of piled elongated keratocytes and collagenous connective tissue are observed in the posterior stroma of the wild-type (WT) embryo cornea. B: This lamellar structure is not observed in the anterior stroma of the mutant cornea (asterisk). Neovascularization (NV) is also seen in the mutant stroma. Bar, 5 μm.

Mentions: In our previous study, we did not fully examine corneal stroma abnormalities in the keratin 12 promoter-driven conditional expression of gof-β-catenin (Krt12rtTA/Wt/tet-O-Cre/Ctnnb1floxE3/Wt triple transgenic) mouse embryos [14]. In the present study, the mutant embryo with Krt5-Cre-driven gof-β-catenin overexpression induced hypercellularity with increased thickness in the stroma as early as E13.5 (Figure 4A,B) along with epithelial β-catenin immunostaining (Figure 4I-P). An ultrastructural examination was performed with the E18.5 embryos to examine the potential anomaly of keratocytes and the extracellular matrix. The WT corneal stroma exhibited a well-organized lamellar structure of keratocytes and collagen fibers at E18.5 (Figure 8A), while the keratocytes of the mutant stroma showed a disorganized distribution with less extracellular matrix in between the cells (Figure 8B). Such abnormality was more prominent in the anterior stroma than in the posterior stroma (Figure 5D). Neovascularization was also observed in the mutant stroma (Figure 8B).


Disruption of eyelid and cornea morphogenesis by epithelial β-catenin gain-of-function.

Mizoguchi S, Suzuki K, Zhang J, Yamanaka O, Liu CY, Okada Y, Miyajima M, Kokado M, Kao WW, Yamada G, Saika S - Mol. Vis. (2015)

Ultrastructure of the posterior corneal stroma of WT and mutant embryos at E18.5. A: Lamellar structure of piled elongated keratocytes and collagenous connective tissue are observed in the posterior stroma of the wild-type (WT) embryo cornea. B: This lamellar structure is not observed in the anterior stroma of the mutant cornea (asterisk). Neovascularization (NV) is also seen in the mutant stroma. Bar, 5 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4522241&req=5

f8: Ultrastructure of the posterior corneal stroma of WT and mutant embryos at E18.5. A: Lamellar structure of piled elongated keratocytes and collagenous connective tissue are observed in the posterior stroma of the wild-type (WT) embryo cornea. B: This lamellar structure is not observed in the anterior stroma of the mutant cornea (asterisk). Neovascularization (NV) is also seen in the mutant stroma. Bar, 5 μm.
Mentions: In our previous study, we did not fully examine corneal stroma abnormalities in the keratin 12 promoter-driven conditional expression of gof-β-catenin (Krt12rtTA/Wt/tet-O-Cre/Ctnnb1floxE3/Wt triple transgenic) mouse embryos [14]. In the present study, the mutant embryo with Krt5-Cre-driven gof-β-catenin overexpression induced hypercellularity with increased thickness in the stroma as early as E13.5 (Figure 4A,B) along with epithelial β-catenin immunostaining (Figure 4I-P). An ultrastructural examination was performed with the E18.5 embryos to examine the potential anomaly of keratocytes and the extracellular matrix. The WT corneal stroma exhibited a well-organized lamellar structure of keratocytes and collagen fibers at E18.5 (Figure 8A), while the keratocytes of the mutant stroma showed a disorganized distribution with less extracellular matrix in between the cells (Figure 8B). Such abnormality was more prominent in the anterior stroma than in the posterior stroma (Figure 5D). Neovascularization was also observed in the mutant stroma (Figure 8B).

Bottom Line: The ultrastructure of the ocular tissues of the E18.5 embryos was also examined.The mutant stroma exhibited impaired keratocyte differentiation with accelerated cell proliferation and reduction in the accumulation of collagen type I.The mutant embryos also showed hyperproliferative nodules in the ocular surface epithelia with anomaly of cornea-type epithelial differentiation and the absence of the epithelial basement membrane.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Wakayama Medical University School of Medicine, Wakayama, Japan.

ABSTRACT

Purpose: To examine the developmental pathobiology of the eyelid and the cornea caused by epithelial β-catenin gain-of-function (gof) during mouse embryogenesis.

Methods: Compound mutant mice (Ctnnb1(GOFOSE) , gof of β-catenin in the epidermis and the ocular surface epithelium) were generated by time-mating keratin 5-promoter-Cre recombinase (Krt5-Cre) and Ctnnb1(fE3/WT) (floxed exon 3 of Ctnnb1) mice. Eyes obtained from wild-type (WT) and mutant embryos at various gestation stages until E18.5 were examined with histology and immunohistochemistry. The ultrastructure of the ocular tissues of the E18.5 embryos was also examined.

Results: Expression of the gof-β-catenin mutant protein in the epidermis severely impaired eyelid morphogenesis at E15.5, E17.5, and E18.5. The mutant stroma exhibited impaired keratocyte differentiation with accelerated cell proliferation and reduction in the accumulation of collagen type I. The mutant embryos also showed hyperproliferative nodules in the ocular surface epithelia with anomaly of cornea-type epithelial differentiation and the absence of the epithelial basement membrane.

Conclusions: Expression of the gof-β-catenin mutant protein in basal epithelial cells disrupts eyelid and cornea morphogenesis during mouse embryonic development due to the perturbation of cell proliferation and differentiation of the epithelium and the neural crest-derived mesenchyme.

No MeSH data available.


Related in: MedlinePlus