<p>A. Growth curves for <i>TK</i> RNAi cells or <i>TK</i> RNAi cells containing a Tet-regulated expression plasmid for <i>Hs</i>DCTD. Cell growth was monitored ±Tet for the indicated days. Error bars represent SD for triplicate biological replicates. Inset shows a Western blot of <i>Hs</i>DCTD expression ± Tet at 48 h. B. qPCR analysis of <i>Tb</i>TK mRNA expression in both the <i>TK</i> RNAi cell line and the <i>TK</i> RNAi <i>Hs</i>DCTD rescue line (±Tet 48 h). Error bars represent SEM for triplicate data. Data were normalized to the -Tet control, which is in the background of the single allele TK knockout. C. Growth analysis of <i>TK</i> null cells expressing either FLAG-tagged <i>Tb</i>TK (c-null) or FLAG-tagged <i>Hs</i>DCTD under the control of the Tet promoter. Error bars represent SD for triplicate biological replicates. Inset shows western blot analysis of the <i>Hs</i>DCTD <i>TK</i> null cells 2 days and 5 days after Tet withdraw.</p