Purchase this article with an account.
D. Bremond–Gignac, H. Copin, H. Liang, F. Sennlaub, F. Lezot, B. Robert, A. Berdal, F. Behar–Cohen, J.–C. Jeanny; Developmental Expression of Msx1 in Anterior Segment in Transgenic Mice . Invest. Ophthalmol. Vis. Sci. 2006;47(13):5633.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Recent studies demonstrated that early ocular developmental processes are controlled by a complex network of regulatory molecules, such as Pax6, Pax2, Six3, Six6, Vax1, Mitf, Chx10, Lhx2, Rx, Otx1and 2, cyclin D1, p27kip1, BMP4, and BMP7. In the Msx1–/–, Msx2–/–, double mutant mouse, eye development arrests early in embryogenesis and forced expression of Msx2 perturbs BMP signalling in developing eye. This is accompanied by an increase in retinal cell death and a reduction in cell proliferation. Together, these molecules are involved in different ocular compartments, regulate cell proliferation and apoptosis. We studied expression of Msx1 in anterior segment in knock–in transgenic mice to understand the implication of this regulatory gene in the development of anterior segment and corneal limbus.
Msx1 (nLacZ) transgenic mice embryos with in situ hybridization and beta–galactosidase activity were obtained. Mice embryos (from E 9,5 to E16,5 ) were postfixed in 4% paraformaldehyde in PBS overnight at 4°C. Mounting was performed after freezing in liquid nitrogen in OCT compound. Histologic cryostat sections of 10–µm thick with beta–galactosidase enzymology identified Msx1 protein expression pattern. Localisation was observed in optic microscopy.
Expression of Msx1 was found in growing mice, specifically in the sites where Msx1 plays an early morphogenetic role, at the level of cornea and in lens epithelium with variations in different stages of development. At stage E11,5 cornea and anterior lens epithelium appeared immunostained and at stage E13,5 only the mean cellular layer of the cornea. The expression was more intense in the limbal area than in the center of the cornea.
Previous studies demonstrated the early death of Msx1 null mutant mice, but Msx1 knock–in mice can confirm this gene is possibly involved in ocular surface development as OTX gene. Comparison between histological description of the eye in gene mutant and normal mice is evaluated. Msx1 and Otx1 gene are probably required for anterior segment system (corneal epithelium, corneal endothelium, corneal limbus and lens) and eye development and could be confirmed using Otx1–/– and Msx1–/–; Msx2–/– mutant mouse.
This PDF is available to Subscribers Only