Single-cell PCR analysis confirms differential gene expression patterns in CLP and FrA populations. The figure shows the collected result of multiplex single-cell RT-PCR from indicated populations. CLP (Rag1^low, Rag1^high, and λ5Tg⁺) and FrA (Rag1^high and λ5Tg⁺) subpopulations were sorted as shown in Figure 1A. The dots represent detected expression of the indicated gene. Each horizontal line of dots represents a single investigated cell. Dots indicate that a RT-PCR product could be detected for a given gene in an investigated cell. The values on top of the data panel indicate the number of cells expressing the indicated gene (top portion of the panel) and the percentage of cells expressing the indicated gene of all cells expressing any gene (bottom portion of the panel).