Abstract
Purpose: :
Crystallin genes play a predominant role in maintaining the structure of the lens and may also be expressed in non-lens eye tissues. In previous studies, we reported a spontaneous mutation in the βA3/A1crystallin gene, Nuc1, with a novel eye phenotype. The current study was undertaken to analyze the expression of this gene during eye development in both wildtype and Nuc1 rats and to delineate its role in eye development.
Methods: :
Expression of βA3/A1-crystallin was analyzed by in situ hybridization (ISH) and/or immunohistochemistry (IH) during embryonic and post-natal eye development of wildtype and Nuc1 rats. For IH, an antibody was generated to a peptide sequence common to both βA3 and βA1polypeptides, and for ISH full-length anti-sense and sense probes were generated by standard protocols.
Results: :
βA3/A1-crystallin was differentially expressed in different tissues of the eye with predominant expression in the lens. The lens expression was induced as early as E12.5 in the lens vesicle. Expression was primarily in the lens fibers and this pattern was seen throughout embryonic development and in the mature lens. Interestingly, expression in the retina is induced only in the first few days of post-natal development with no expression during embryonic stages. At 2 weeks post-natal, robust expression of the mRNA was seen predominantly in the ganglion cell layer and in the inner nuclear layer. In comparison to wildtype lens, Nuc1 lenses showed various developmental abnormalities with changes in the expression pattern for βA3/A1-crystallin.
Conclusions: :
Expression of βA3/A1-crystallin is controlled differentially in various eye tissues with lens being the most predominantly expressed tissue. Our studies provide novel evidence that βA3/A1-crystallin likely plays a pivotal role in normal development and function of the eye, particularly in the remodeling process.
Keywords: crystallins • development • gene/expression