세포 중요 유전자군의 고효율 전달 및 발현 시스템을 이용한 정상 세포에서의 방사선 저항성 및 민감성 관련 유전자 조합 탐색

Abstract

The purpose of this research is to characterize the combinations of genes that affect radiation resistance and sensitivity in normal mammalian tissue cells. Although similar studies have been performed in many established cell lines, we specifically focused on the response of normal mouse bone marrow cells to obtain the results that are more relevant to the in vivo radiation response. For this purpose, we screened retroviral cDNA library proto-oncogene, kinase, and phosphatase gene families for the candidate genes that are related to the radiation sensitivity and resistance in normal bone marrow cells. By limiting the candidate genes to several important gene families, more thorough screen and characterization of the genes (or gene combinations) that are affecting cellular response to radiation was possible. In addition, by using retroviral cDNA library, rather than plasmid cDNA library, we were able to efficiently transduce cDNAs into normal mouse bone marrow cells thus allowing gene screen in a relatively normal context. One notable experimental innovation included in this study is to adopt Next Generation Sequencing (NGS) strategy to follow cDNA frequencies of cells harboring individual cDNA at a population level. Using this strategy, we were able to quickly determine candidate genes that might be related to cell survival or cell death in response to γ-irradiation. In particular, NGS approach allows screening genes involved in radiation sensitivity in addition to the radiation resistance. From this study, we concluded that HOXD8, HOXA6 genes are involved in radiation-resistance, and RABL3, TLX2 genes are involved in radiation-sensitivity in primary bone marrow cells. The study we report here will be a valuable model system in systematically screening the genes (or gene combinations) involved in radiation response of normal cell.