“…Mammalian lenses contain primarily a-crystallins (Mr 700,000-1,200,000), 0-crystallins (Mr 50,000-300,000), and 'y-crystallins (Mr 21,000) (1,6,7). The y-crystallins are highly enriched in the lens nucleus as a result of differential synthesis during development, and they undergo selective degradation and insolubilization with aging (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). They are monomeric basic proteins, rich in sulfhydryl groups (19)(20)(21)(22).…”