Large-scale sequencing of the rabbit corneal endothelial cDNA library

Purpose. This study sought to identify novel or active genes in corneal end othelial cells with description of the gene-expression profile. Methods. We performed the single-pass sequencing of 1,000 clones from a rabbit corneal endothelial cDNA library. Inserts of the library were amplified by polymer ase chain reaction (PCR), sequenced, and compared with several databases. W e used four database similarity search programs: FASTA, BLASTN, TBLASTX, an d BLASTX. Results. Of the sequences generated, 618 (61.8%) showed sequence homology with known genes, whereas 192 (19.2%) matched previous reported ex pression sequence tags (ESTs) and 174 (17.4%) showed no sequence similarity . Among the homologous clones to known genes are collagen type VIII, secret ed protein acidic and rich in cysteine (SPARC), lysyl oxidase, phosphatidyl choline-2-acylhydrolase, and thrombospondin. Several matched ESTs, and no m atched clones that showed high frequency were also detected. Conclusion. La rge-scale sequencing can be useful in obtaining a profile of the active gen es. Several ESTs showed relatively frequent expression, suggesting that the se genes may have important functions in the corneal endothelium.