Fig. 5
Internalization of eDNA by Krebs-2 cells upon additional rounds of incubation. a Internalization of pUC19 plasmid was analyzed when this plasmid was added every 30 min (groups 2–6) following 1-h pre-incubation with 1 μg pUC19 (group 1). Shown is the total number of colonies obtained by transforming competent E. coli with DNA from 106 Krebs-2 cells incubated with pUC19 DNA; b representative image of E. coli colonies that formed as a result of transformation of DNA isolated from Krebs-2 cells that received additional pUC19 DNA 2.5 (group 5) and 3 h (group 6) after the pre-incubation step. Many more colonies are visible on the group 6 half of the plate; c FACS analysis of Alu-TAMRA dsDNA internalization by Krebs-2 cells 3 h following the pre-incubation with the same DNA; d fluorescence microscopy analysis of Krebs-2 cells pre-incubated with Alu-TAMRA DNA, followed by addition of Alu-FITC DNA. Cells internalizing fluorescent probes are marked with arrows; e cell cycle profiling of the total (unsorted) cell population (top), and TAMRA+ Krebs-2 cells (bottom). Percentages of cells found in G1, S, and G2/M phases are shaded in red