Abstract
Abstract: :
Purpose: LEP503 is a novel gene product isolated from lens epithelial cells of mature rat by a subtractive cDNA cloning strategy. This gene is highly conserved in different vertebrate species and developmentally regulated in postnatal rat lens, suggesting that LEP503 may be an important lens epithelial gene involved in the processes of epithelial cell differentiation. The purpose of this study was to determine the expression patterns of LEP503 mRNA during embryonic and early postnatal ocular development. Methods: RACE–PCR was used for isolation of mouse LEP503 cDNA from mouse lens. A 524–bp mouse LEP503 cDNA fragment that was generated from 5’–RACE with mouse lens RNA was used as a template to prepare antisense and sense riboprobes. Tissue samples from embryonic day 9.5 (E9.5) through postnatal day 14 (P14) were collected from C57BL/6 strain mice. The specimens were fixed in paraformaldehyde, histologically processed, and assayed for LEP503 mRNA expression by in situ hybridization. Results: The transcripts of LEP503 are first observed in the elongating fiber cells from the posterior lens vesicle at E11.5 to 12.5. During the subsequent embryonic development of the lens, LEP503 transcripts are most abundant in the primary fiber cells and reach the highest level at E15.5 to 16.5. The expression level of LEP503 starts to decrease at E17.5 and reaches the lowest level at E19.5. The expression of LEP503 is upregulated again at postnatal day 1 (P1) and the transcripts start to be found in anterior epithelial cells and elongating fiber cells in the equatorial region of lens. During the subsequent postnatal development of the lens up to P14, the expression level of LEP503 is continuously increased and the transcripts become abundant in the entire anterior epithelium surface and the equatorial region where the epithelial cells start to elongate to differentiate into secondary fiber cells. Conclusions: The expression patterns of LEP503 are temporally and spatially regulated during the early development of the mouse lens, suggesting that LEP503 may be important in early lens development and later in lens epithelial cell differentiation.
Keywords: gene/expression • in situ hybridization • transcription