A Study on CArG Elements in Radiation-Mediated Gene Expression / 上海第二医科大学学报

ABSTRACT

Objective To construct luciferase reporter plasmid containing synthetic CArG elements and to investigate their radiation-inducible property in tumor cells. Methods Insert chimeric regulation elements consisting of nine tandem-repeat copies of CArG sequence (CCATATAAGG) and CMV IE basal gene promoters into pGL3-Basic vectors to construct luciferase reporter plasmids. Tumor cells(HeLa, A549 and HepG2) were transiently transfected by reporter plasmids using lipofectamine, and transfected cells were irradiated by ?-ray with different doses. After 36 h, we assayed the level of reporter gene expression. Results The CArG elements could successfully induce the expression of a downstream reporter gene following irradiation, with maximal expression seen after 3 Gy irradiation. Conclusion The synthetic CArG elements are responsive to low dose of radiation and are able to enhance down-stream gene expression. It is expected to be the essential potential for future application of radiogenetic cancer therapy.