[10p-N207-1~16] 12.6 Nanobiotechnology

[10p-N207-8] Single-Molecule Detection of Nucleic acid analog of intracellular RNA by quantum measurement method

〇Takahito Ohshiro¹, Yuki Komoto¹, Masamitsu Konno², Ayumu Asai¹, Hideshi Ishi³, Masateru Taniguchi¹ (1.Sanken, Osaka Univ., 2.Tokyo Univ. of Sci., 3.Med. Osaka Univ.)

Keywords:RNA/DNA, Tunnel-Current, Single-Molecule Detection

FTD is an anticancer drug, which is a fluoride derivative of uracil molecule. We investigated the FTD substitutions in DNA samples extracted from FTD-resistant and non-resistant strains of colorectal cancer by using a single-molecule quantum measurement method. It was found that thymine was replaced with FTD by about 5% in the DNA binding region of the down-regulation of TP53 in the FTD-resistant cell line. In addtion, it was found that the gene expression level for the downstream of TP53 in the resistant strain was changed, which was consistent with the results by our single-molecules detection. This single-molecule detection method of the DNA in the cell would be applicable for the evaluation of gene expression at single-molecular level.