Stabilization of mRNA templates in bovine lens epithelial cells

Through the use of actinomycin D, it has been shown that the half-life of α-, β- and γ-crystallin mRNA in bovine lens epithelium increases with lens age. Crystallin synthesis in epithelial cells from embryonic lenses was potently inhibited by actinomycin D; the synthesis of these same proteins in adult lens epithelial cells was not affected. In both cases, all RNA synthesis was completely turned off by the antibiotic. Since the mitotic index of epithelial cells in embryonic lenses is much greater than that of the adult epithelial cells, our results indicate that stabilization of the protein-synthesizing templates found in adult epithelial cells may be related to the decreased replicative activity of these cells.