Fig. 7. Differentiation ability of Rex1^-/Oct3/4⁺ cells into mesodermal and neural lineages. (A) Dot-plots of analysis at day 0 and day 4 for mesodermal induction from unselected Rex1-tk2 knock-in ES cells. Percentage of Flk1⁺/E-cadherin^- cells (indicted by rectangles) was measured by analyzer. (B) The results of induction of mesoderm from Rex1⁺/Oct3/4⁺ and Rex1^-/Oct3/4⁺ populations selected with GANC and puromycin. Note that Rex1^-/Oct3/4⁺ (PrE-like cells) differentiated into mesodermal cells more efficiently and with faster kinetics than non-fractionated ES cells. (C) Analysis of induction of neural cells (dot-plot on day 4). Anti-NCAM antibody and Alexa-633-conjugated anti-goat IgG antibody were used as first and second antibodies, respectively, for measurement of the proportion of neural cells. Green line, control ES cells stained with only secondary antibody; blue line, fraction of Oct3/4⁺ cells on day 5; red line, enriched Rex1^-/Oct3/4⁺ fraction on day 5. (D) Summary of experiment for induction of neural cells on days 2, 4 and 5.