ErbB signaling is not required for stem cell self-renewal.

<p>(A) Cartoon of drug treatment timeline for single and double regeneration assays. (B) Quantitation of average regenerated dorsal melanocytes for each treatment in (A). Error bars represent standard deviation, - P>0.05 (Student's t-test, N = 10 for single regeneration, >5 for double regeneration). As previously shown (see <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1000544#pgen-1000544-g002" target="_blank">Figure 2</a>), when larvae are treated with AG1478 after 2 dpf, they regenerate normally following a single round of MoTP treatment. When animals are treated with two rounds of MoTP (from 2–4 dpf and from 5–7 dpf) they regenerate slightly less melanocytes than a single round by 9 dpf. To test whether AG1478 treatment would block stem cell self-renewal, we treated animals with MoTP and AG1478 from 2–4 dpf, and then with a second round of MoTP from 5–7 dpf. These animals regenerated melanocytes similar to non-AG1478 treated larvae for double regeneration (P = 0.9).