[The crystalline lens as a model for studying the cellular and molecular mechanisms of differentiation in the adult organism].

This review summarizes the published and authors own data about characteristics of expression of tissue-specific lens proteins (crystallins) during differentiation of lens epithelial cells into lens fibers in adult mammals, birds, reptiles, and amphibians. Information is analyzed about the presence, synthesis, and localization of different crystallins in lens epithelium and fiber cells of lens cortex and nucleus which correspond to sequential stages of lens cell differentiation. The data available suggest that morphologically similar differentiation of lens epithelial cells into fibers in different classes of vertebrates is accompanied by different programs for activation (and/or increase) of tissue-specific protein synthesis.