Abstract
Abstract: :
Purpose: To investigate whether Pb2+ exposure will induce modifications of the lens structural proteins. Methods: In vivo: Fisher 344 rats were orally exposed for 5 weeks to 2000 ppm of lead acetate in their drinking water. Following euthanization, lenses were collected and frozen at -70C until solubilization. In vitro: Lenses were collected from Sprague-Dawley rats and cultured in the presence of Pb2+ for 4 days and then stored at -70C until solubilization. 2D-PAGE: Lenses were solubilized in 8 M urea containing DTT and CHAPS, applied to IPG strips, and focused according to charge. Following equilibration in SDS buffer, the IPG strips were loaded onto polyacrylamide gels and separated according to size. After visualization, selected spots were identified by MALDI-MS. Results: From the visualized 2D gels, additional spots correlating to modified alpha and beta crystallin were evident in the Pb2+ exposed lenses as compared to the control lenses. The identification was confirmed with MALDI-MS. Conclusion: Pb2+ exposure does alter the structural protein profile in the lens.
Keywords: 378 crystallins • 525 protein modifications-post translational • 338 cataract