Fig. 5. F-5caC was not decarboxylated to F-dC in soluble nucleoside/nucleotide pool. (a) Schematic overview of the assumed pathway of decarboxylation of F-5caC in nucleoside/nucleotide soluble pool. F-5caC (MP, DP, and TP) and F-dC (MP, DP, and TP) refer to the form of nucleoside, monophosphate, diphosphate, and triphosphate, respectively. (b) Extracted-ion chromatograms for monitoring F-5caC and F-dC in the soluble pool. (c) Quantitative data of F-5caC and F-dC in the soluble pool after feeding 300 μM of F-5caC for 3 d. (d) Quantification of F-dC level in genomic DNA after feeding of F-dC with diverse concentrations to HEK293T cells for 3 d.