Regionality of Glycated Calf Lens Crystallin Subunits Demonstrated by Lectin Staining

Abstract

Nonenzymatic glycation of lens crystallins involves a bimolecular condensation reaction between a reducing sugar and the ε-amino-group of a lysine residue^1-3. Glycation^3-5 and a subsequent browning reaction^4,5 appear to be linked with age related protein aggregation and insolubilization^6,7. Ageing of the bovine lens has specifically been attributed to the glycation of: HM-crystallins, ß-crystallins and nuclear γ-crystallins in the native form. In contrast, in the equator (EQ), anterior cortex (AC) and posterior cortex (PC) of bovine lenses younger than 10 years, α-crystallin was not glycated⁸. The various bovine lens crystallins in the unfolded subunit form appear to be increasingly glycated with increasing intrinsic age. Uptil now, it was not yet known which carbohydrate(s) are involved in crystallin glycation.

This study is to characterize the expression of different types of glycated crystallin subunits in calf lens sections of different localization i.e, intrinsic age.