Abstract
Purpose: :
To compare the gene expression and protein expression between the central epithelial cells and the peripheral epithelial cells in bovine lens.
Methods: :
The anterior epithelial cells adherent to lens capsule were dissected into central (10.5 mm diameter) and peripheral regions. Total RNAs were extracted from epithelial cells of both parts of pooled bovine lenses and amplified by PCR. The products were incorporated with fluorescent markers (the central marked with cy3, while the peripheral with cy5) and then hybridized to a microarray containing 7548 ESTs (Chipscreen Biosciences, Ltd.). The differences between two samples were analyzed. Water–soluble proteins of the central and peripheral epithelial cells from 32 bovine lenses were extracted and separated by two–dimensional polyacrylamide gel electrophoresis (IEF/SDS–PAGE, 2DE). After Coomassie blue staining, different spots on two 2DE gels were selected and identified by matrix–assisted laser desorption ionization time of flight mass spectrometry (MALDI–TOF–MS, Amersham Biosciences).
Results: :
There were 306 transcripts displayed remarkable difference between two parts by means of microarray analysis. Compared to the central lens epithelia, 117 genes were down–regulated and 189 genes up–regulated in the peripheral part. Those different expressed genes were mainly related to metabolism, cell cycle, stress response and cytoskeleton/motility bioprocesses. In 2DE and MALDI–to–MS analysis, 39 pairs of spots appeared to be intensive on one gel while were weak on the other one, including 20 proteins up–regulated in the central and 19 proteins in the peripheral epithelial cells. All proteins expressed differently can be classified into metabolism, transcription, transducers and cytoskeleton/motility related–proteins.
Conclusions: :
There are different genome/proteome activities during lens epithelial differentiation from central area to periphery. The alterations of both transcripts and proteins of lens epithelia cells from the central to peripheral regions showed the similar functional classification.
Keywords: gene microarray • proteomics • crystalline lens