Altered Expression Patterns of the Sumoylation Enzymes E1, E2 and E3 Are Associated with Glucose Oxidase- and UVA-Induced Cataractogenesis.

Protein sumoylation is a well established regulatory mechanism that regulate chromatin structure and dynamics, cell proliferation and differentiation, stress response and cell apoptosis. In the vertebrate eye, we and others have shown that sumoylation plays an indispensable role in regulating eye development. During stress induction and aging process, the ocular tissues gradually loss their normality and develop major ocular diseases such as cataract and aging-related macular degeneration. We have recently demonstrated that sumoylation actively regulates differentiation of lens cells, whether this process is implicated in lens pathogenesis remains to be investigated. In this study, we have demonstrated that transparent mouse lenses treated with glucose oxidase and UVA irradiation undergo in vitro cataract formation. Under such conditions, the expression levels of both mRNA and protein for the three major sumoylation enzymes were significantly changed. Our results suggest that altered expression patterns of the sumoylation enzymes are associated with oxidative stress-induced cataractogenesis.