Evidence for a calcium activated protease specific for lens intermediate filaments

The calcium mediated loss of intermediate filament protein from lens cytoskeletal preparations was examined by soft laser scanning densitometry of polyacrylamide gels. The time course of proteolysis by the lens Ca++ activated proteinase and inhibition by EGTA or PMSF and leupeptin were also determined. Proteolytic breakdown products were identified on electroblots with specific antiserum to vimentin.