Abstract
Purpose: :
To separate total lens proteins of congenital inherited cataract in mice and observe the alteration of protein after gene mutation.
Methods: :
A spontaneous γS–crystallin mutated mice transmitted as a recessive trait were studied. We analyzed differential displayed proteomics of cataract and normal crystalline lens of 5 weeks’ mice. We applied a sample of either 882µg or 190 µg protein. The proteins were separated using immobilized PH gradient (IPG) two–dimensional electrophoresis (2–DE) and colloidal Coomassie Brilliant Blue (CBB) staining. Image analysis was carried out using PDQuest 7.30 software package. Partial significant differentially proteins in gel were identified by matrix assisted laser adsorption/inoization–time of flight–tandom mass spectrometry (MALDI–TOF–MS/MS).
Results: :
It could separate the low–abundance proteins when we applied a 882µg sample and the high–abundance proteins, a 190µg sample. We had detected 417 spots in cataract mice and 370 spots in normal ones when a 882µg sample was added. When cataract gel acted as the reference gel, the matched ratio was 53% in normal lens and 67% in cataract. The differential expression analysis showed that there were 160 matched spots between cataract and normal lens. 242 spots were detected only in cataract and 163 spots were detected only in normal lens. Compared with the expression profile of normal lens, there were 9 overexpression spots (>4 fold) and 9 downexpression (<4 fold) spots in cataract. We chouse and identified 5 spots in cataract such as beaded–filament structure protein (BFSP), BFSP, αA,Crybb1 and ßB3 crystallin. As a 190µg sample was added, We had detected 57 spots in cataract mice and 60 spots in normal ones.γs,αB,ßA2,γF and αB crystalline were identified.γs crystalline was found only in the normal mice.
Conclusions: :
The protein profile of congenital inherited cataract displayed obviously difference compared to that of normal lens. Lower sample can well separate the high–abundance proteins of crystalline lens. Mutant gene can alter the change of the downstream proteins. 2–DE and mass spectrometry can help to assess and analyze different proteins as a novel approach.
Keywords: cataract • proteomics • crystalline lens