Comparative proteomic analysis of lens in congenital inherited cataract mice

AIM: To separate total lens proteins of congenital inherited cataract in mice and to observe the alteration of proteins after gene mutation.METHODS: We studied the mice with a spontaneous mutation of crystallin gamma S (Crygs) transmitted as a recessive trait. Total proteins were extracted and separated using immobilized pH gradient (IPG), two-dimensional electrophoresis (2-DE) and colloidal Coomassie brilliant blue (CBB) staining. The image analysis was carried out using PDQuest 7.30 software package. Several significantly differential proteins in gel were identified by matrix assisted laser adsorption/ionization-time of flight-tandem mass spectrometry (MALDI-TOF-MS/MS). RESULTS: As the 882 μg sample was added, we detected (417±53) spots and (370±41)spots in cataract and normal lens, respectively. As the 190 μg sample was loaded, we detected (60±7) spots and (57±5) spots in cataract and normal lens, respectively. Seven kinds of differential proteins were identified, including BFSP/filensin, γS, γF, βA1, βB1, βB2 and αB. In crystalline lens of mutant mice, γS and beaded-filament structure protein (BFSP/filensin) were not detected. γF was down-expressed (＜4 fold) while βA1, βB1, βB2 and αB were over-expressed (＞4 fold) in mutant cataract. The latter proteins were less MW than normal, suggesting that they were possibly truncated.CONCLUSION: 2-DE and mass spectrometry can help to assess and analyze the function of proteins as a novel approach. The mutant Crygs gene can lead to the abnormity of γS crystallin, which can induce the changes of skeletonal protein (BFSP/filensin) and other crystallins (γF, βA1, βB1, βB2 and αB), and then evoke cataract secondarily.