Figure 4. 2-D Electrophoresis map showing identities of lens cortical water-soluble (WS) proteins of a 2.5-month-old guinea pig. The major proteins of the lens cortex were identified by MALDI mass spectrometry. The ratio of cortical αA-crystallin to αB-crystallin was 6.5:1 as quantified by image analysis software, Image J. All β-crystallins and γA-C-crystallin were detected, but no protein signatures were detected for γD-, γE-, and γF-crystallin. The gel contains 47 spots, 37 of which have been identified, with some proteins as intact or truncated crystallins. Proteins were stained with Coomassie Blue G-250. The symbol ? indicates presumptive protein identification.