Isoaspartyl protein damage and repair in mouse retina.

ABSTRACT:

Purpose

To determine the propensity of retinal proteins for spontaneous damage via formation of isoaspartyl sites, a common type of protein damage that could contribute to retinal disease.

Methods

Tissue extracts were obtained from retinas and brains of control mice and from mice in which the gene for protein L-isoaspartate O-methyltransferase (PIMT; an enzyme that repairs isoaspartyl protein damage) was knocked out. PIMT expression in these extracts was measured by Western blot, and its specific activity was assayed by monitoring the rate of [(3)H]methyl transfer from S-adenosyl-[methyl-(3)H]L-methionine to γ-globulin. Isoaspartate levels in extracts were measured by their capacity to accept [(3)H]methyl groups via the PIMT-catalyzed methylation reaction. To compare molecul

SUBMITTER: Qin Z 

PROVIDER: S-EPMC3954159 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature