Changes in the DNA breakage and crystallin synthesis of embryonic chicken lenses cultured in a tryptophan-deficient medium

In vitro experiments were performed in order to understand the biochemistry of tryptophan-deficient cataract. Eleven-day-old embryonic chick lenses were cultured in vitro for 3 hr, one and three days in a tryptophan-deficient medium. DNA breakage was followed on sucrose gradient and water-soluble protein synthesis was analysed by SDS-PAGE coupled with fluorography. A medium lacking tryptophan delays the DNA degradation and decreases the synthesis of all soluble proteins including the crystallins.