DIFFERENTIAL SYNTHESIS OF CRYSTALLINS IN THE DEVELOPING RAT EYE LENS

The patterns of protein synthesis in rat lenses ranging in age from newborn to 4 months were compared. After incubation of lenses in [35S]methionine-containing medium it was possible to identify the de novo synthesized crystallins by two-dimensional gel electrophoresis and fluorography, in combination with peptide mapping and immunoblotting. It was found that the relative synthesis of αA and βA3 stays fairly constant in rat lenses of all investigated ages. The relative synthesis of βB2 and γs shows a pronounced increase with age in these post-natal lenses. A differential decrease can be observed in the relative synthesis of the other six γ-crystallins (γA-γF). There appears to be a good correlation between the changes in relative synthesis of the various crystallins and previously reported alterations in mRNA levels, although certain mRNAs exhibit marked differences in translational efficiency. © 1990.