IPTG와 젖당을 이용한 유전자 유도 발현 시스템 개발

Abstract

The technique to regulate gene expression is necessary to study the functions of genes and to treat diseases through gene therapy. Various inducers such as Tetracycline, Isopropyl β-D-1-thiogalactopyranoside (IPTG) and Doxycycline have been used to control gene expression. Among these system, the Lac operon system is one of the most used system. IPTG, an inducer used in the Lac operon system, has a high affinity for the repressor and is known to penetrate rapidly into mammalian cells and has low toxicity. Therefore, in this study, I made a inducible expression system of target gene that can regulate gene expression by IPTG in the mammalian cells using Lac operon system. In addition, unlike other inducible gene expression vector system using Lac operon, this study confirmed that gene expression can be regulated by Lactose, which is readily available from around, and gene expression is controlled more efficiently by treating IPTG and lactose together. In order to regulate gene expression more efficiently, the number of operators was controlled so that the gene expression could be strongly inhibited when the inducer was not treated. In addition, I used CAG enhancer and CMV promoter-mini, which can strongly induce gene expression in animal cells, to further enhance gene expression when treated with inducers. The CMV promoter-mini was designed to reduce the size of the vector and increase its efficiency using the minimal sequence with the function of the promoter in the CMV promoter. This study confirmed that lactose as well as IPTG could be used as an inducer to regulate gene expression in mammalian cells. Lactose is a disaccharide contained in dairy products such as milk and is easily consumable. Therefore, regulation of gene expression using lactose in combination with IPTG is expected to have great benefits in gene therapy.