Incubation of soluble proteins from rat lens with the protease calpain II caused the precipitation of β-crystallin polypeptides. Two-dimensional electrophoresis and sequence analysis identified β-crystallin polypeptides both before and after their precipitation by calpain II. β-crystallin polypeptides precipitated by calpain were cleaved at their NH2-terminal extensions. These cleavage sites were similar to cleavage sites occurring in β-crystallin polypeptides precipitated during formation of experimental cataract induced by an overdose of selenite. These data suggested that calpain II caused β-crystallin insolubilization during cataract formation, and indicated that the process can be mimicked in vitro.
|Original language||English (US)|
|Number of pages||6|
|State||Published - Jun 21 1993|
ASJC Scopus subject areas
- Structural Biology
- Molecular Biology
- Cell Biology