Retinal selectivity of gene expression in rat retinal versusbrain capillary endothelial cell lines by differential display analysis

[摘要] Purpose: The retina is a neural tissue especially differentiated forvision and, thus, the inner blood-retinal barrier (inner BRB) specificmolecules may play an essential role in maintaining neural functions inthe retina. The purpose of the present study was to identify selectivelyexpressed genes at the inner blood-retinal barrier compared with theblood-brain barrier (BBB).Methods: A comparison of expressed genes between conditionallyimmortalized rat retinal (TR-iBRB) cell lines and brain capillaryendothelial (TR-BBB) cell lines was performed using mRNA differentialdisplay analysis and quantitative real time PCR analysis. The ratM-cadherin gene was cloned by performing 5' RACE, and its proteinexpression was detected by immunoblot analysis.Results: Eight clones were identified as highly expressed genes inTR-iBRB cells including GATA-binding protein-3 (GATA-3), cytosolicbranched chain amino transferase (BCATc), and M-cadherin (cadherin-15).The rat M-cadherin gene was cloned from TR-iBRB cells, for the firsttime, and has >86% amino acid sequence identity to the previouslycloned mammalian M-cadherins. Rat M-cadherin expression in TR-iBRB cellswas much greater than that in TR-BBB cells as far as mRNA and proteinlevels were concerned.Conclusions: M-cadherin, GATA-3, and BCATc are highly expressed inTR-iBRB cells compared with TR-BBB cells and may indeed be involved inunique functions at the inner BRB.

[学科分类] 生物化学/生物物理