[Changes in water-soluble, urea-soluble and membrane intrinsic proteins in human senile cataract]

Gel filtration of water-soluble protein shows a substantial increase in HM+ alpha-crystallin and a marked decrease in beta- and gamma-crystallins in cortical cataract. A decrease in beta 1-crystallin in cortical punctate opaque lenses is also striking. In nuclear cataractous lenses HM+ alpha- and beta-crystallin increase, while gamma-crystallin decreases. The urea-soluble protein from clear lenses contains mainly of alpha beta chain, whereas in cataractous lenses the relative amounts of the 28 and 23ku polypeptides (the components of beta-crystallin) increased markedly. In cataractous lenses the relative amount of membrane intrinsic proteins decreases slightly and it has little statistical meaning.