Figure 7.

Cells are able to resume replication after the removal of 2 mM thymidine during recovery. Cells were treated with 1 mM thymidine for 24 hours, electroporated, and recovered in 2 mM thymidine (1–2 mM) or without thymidine (1-0 mM). At 48, 72, and 144 hours, the culture media was supplemented with BrdU and cells were later assayed by FACS for its incorporation. The 1-0 mM culture reached confluency by 96 hours and was passaged once prior to the 144 hour time point. The w/o ("wash out") samples received 2 mM thymidine in the recovery phase, which was subsequently washed out at 48 and 72 hours, respectively, and later assayed at 144 hours for BrdU incorporation. Position of M1 (BrdU+ marker) was determined by a BrdU(-) control, not shown, and percents indicate the number of cells that are positive for BrdU incorporation out of the total population (25,000 cells).