Functional analysis of human corneal endothelial cells based on the cDNA library

利用基因签名系统建立人角膜内皮细胞的基因表达谱。在人类基因表达数据库中，一个新基因GS3582在CE中与其他组织相比转录水平较高。为了研究CESP-1的生理功能，我们研究了它在人和小鼠体内的组织分布和亚细胞定位。兔和小鼠CESP-1基因序列分别含有242和283个氨基酸的开放阅读框。小鼠CESP-1与小鼠OSAP完全一致。免疫印迹分析显示CESP-1在人角膜上皮、CE、培养的CE、脑、睾丸和卵巢中均有表达。免疫组织化学分析显示，小鼠CESP-1在抗小鼠C-末端OSAP抗体的小鼠角膜上皮和CE中也有表达，但在N-末端OSAP抗体中不表达。在培养的人CE中，CESP-1的亚细胞定位于线粒体。CESP-1的N-末端具有线粒体靶向序列，可能在蛋白质进入线粒体后被加工。CESP-1分布于角膜上皮、CE和培养的人CE，以及脑、睾丸和卵巢。CESP-1定位于培养的人CE线粒体。这些发现可能为CESP-1的生理功能提供一些线索。

The gene expression profile of human corneal endothelium (CE) was established with the gene signature system. A novel gene, GS3582, was abundantly transcribed gene in the CE compared with other tissues using a human gene expression database. To investigate the physiological function of CESP-1, we assessed its tissue distribution and subcellular localization in humans and mice. The rabbit and mouse CESP-1 cDNA sequences contained an open reading frame coding 242 and 283 amino acids, respectively. Mouse CESP-1 is entirely consistent with mouse OSAP. CESP-1 was expressed in the human corneal epithelium, CE, cultured CE, brain, testis, and ovary on western blotting analysis. Mouse CESP-1 was also expressed in mouse corneal epithelium and CE with anti-mouse C- but not N--terminal OSAP Ab according to immunohistochemical analysis. Subcellular localization of CESP-1 to the mitochondria was demonstrated in cultured human CE. The N-terminal of CESP-1, possessing a mitochondrial targeting sequence, may be processed after the protein is imported into the mitochondria. CESP-1 was distributed in the corneal epithelium, the CE and cultured human CE, as well as the brain, testis, and ovary. CESP-1 was localized in the mitochondria of cultured human CE. These findings may provide some clues about the physiological function of CESP-1.