Abstract
Abstract: :
Purpose: To evaluate gene expression profile of corneal endothelium and isolate candidate genes for corneal dystrophy. Methods: We had performed random sequence and similarity search analysis of 1,000 clones from rabbit corneal endothelial cDNA library in the previous study. Forty-five genes, including 6 unknown genes, were listed for the frequently observed cDNAs in the library. We re-analyzed these cDNAs by the similarity search for the latest database including human genome sequence. Newly identified genes were selected for further characterization. Results: Two cDNA sequences (C82954 and C83005) showed significant similarity to newly identified human genes. C82954 showed significant similarity in human ECRG4, which were mapped to human chromosome 2. A rabbit ECRG4 cDNA clone which contained of a 444 bp open reading frame was isolated using 5' rapid amplification of cDNA ends (5' RACE) method. The expression of ECRG4 was observed in the all examined tissues using RT-PCR and in situ hybridization. The sequence of C83005 was similar to the part of polydom gene which was mapped to human chromosome 9. Although we could not isolate the cDNA clone larger than 950 bp in length, RT-PCR study indicated that the expression of this gene was restricted in cornea and spleen. In situ hybridization using C83005 as a probe showed specific labeling of endothelial cells in cornea and lymphocytes in spleen. Conclusion: ECRG4 and polydom are expressed in corneal endothelium. Polydom might be an important gene of corneal endothelium. An accumulation of findings regarding corneal endothelial genes may be important to further the understanding of corneal endothelium.
Keywords: 371 cornea: endothelium • 417 gene/expression • 418 gene mapping