earticle

영어

Glial fibrillary acidic protein (GFAP) is a class-Ⅲ intermediate filament protein specifically expressed in astrocyte of central nerve system (CNS). Studies have demonstrated that approximately 2.2 kilo-base pairs of the human and mouse GFAP promoter region are sufficient to directly regulate GFAP protein or transgene expression in astrocytes and it has been used in numerous studies dealing with the nerve system development, CNS injury-induced process, and disease models. Based on the notion that a pig displays greater taxonomic resemblance to human than a rodent, here we sought to validate a GFAP promoter sequence of a pig as a better representative of that of human. We compared the promoter, mRNA and protein sequences of human, mouse, and swine GFAP and observed that pig and human GFAP show the greatest amount of sequence resemblance. This suggests that the regulatory mechanism underlying swine GFAP expression is more similar to that of human GFAP. A 5.2kb DNA fragment of miniature swine GFAP promoter was isolated from a genomic DNA of miniature pig, Sus scrofa domesticus. In order to validate the key regulatory element of swine GFAP expression, the isolated DNA fragment was further divided into three segments. These partial and full GFAP sequences were then inserted into luciferase reporter systems and their activities were measured by GFAP inducer treatment. The increased expression of swine GFAP-luciferase transgenes was observed upon the treatment of inducer and this suggests that the swine GFAP promoter can be used to induce the expression of a target gene specifically in swine astrocytes. Furthermore, the promoter may be applied to carry out various scientific procedures such the investigation of physiological mechanism underlying gliosis or the generation of CNS disease model.