C-Terminal Truncation of .ALPHA.-Crystallin in Hereditary Cataractous Rat Lens

Synthesis of lens protein in vitro. N-terminal acetylation of alpha-crystallin.

Effect of calpain on hereditary cataractous rat, ICR/f.

The crystallins in the lenses of ICR/f mutation rat, a known hereditary cataract model, were analyzed during cataractogenesis. Opacification of the mutant lenses was found to be accompanied by changes in crystallin structure and composition, including several deletions of the N-terminals of beta-crystallins and low molecular weight alpha- crystallins. Because similar deletions were observed whe...

Immunohistochemical study of calpain-mediated alpha-crystallin proteolysis in the UPL rat hereditary cataract.

The UPL (Upjohn Pharmaceutical Limited) rat is a dominant hereditary cataract model that develops early-onset cataracts (E-type) in rats homozygous for the trait, and late-onset cataracts (L-type) in heterozygous rats. Using antibodies specific to the calpain-proteolyzed forms of alpha-crystallin, we determined their immunohistochemical localization of the L- and E-rat lenses. Immunoreactivity ...

Susceptibility of ovine lens crystallins to proteolytic cleavage during formation of hereditary cataract.

PURPOSE To produce two-dimensional electrophoresis (2-DE) maps for ovine crystallins and examine changes in ovine crystallins during cataract formation. METHODS Soluble and insoluble fractions were isolated from normal, whole lenses of 26-week-old sheep, the proteins separated by 2-DE, and the spots digested with trypsin and subjected to tandem mass spectral analysis. Spot identifications wer...

An unusually long non-coding region in rat lens alpha-crystallin messenger RNA.

Most of the mRNA sequence coding for the alpha A2 chain of the ocular lens protein alpha-crystallin from rat, has been determined by sequencing cloned DNA copies of this mRNA. The 892-base pair cDNA sequence encompasses all but 52 N-terminal amino acids of the alpha A2 chain. It lacks the sequence characteristic for the 22 extra amino acids inserted in the alpha A2 -like chain, named alpha AIns...