<i>In vivo</i> assays of the function of the CEE motifs in selected cardiac enhancers.

<p>(A1, B1, C1) Schematic drawings of the predicted Tin, Pnr, and Doc binding sites within cardiac enhancers as in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003195#pgen-1003195-g005" target="_blank">Figure 5</a> and the positions of the CEE motifs relative to these (green bars). (A2–A5) Mutation of the CEE motifs causes a strong reduction of <i>EgfrE1s</i>-GFP activity in cardioblast progenitors at stage 12 (A2, A3) and in cardioblasts at stage 14 (A4, A5). (B2–B5) Mutation of the CEE motifs leads to the absence of <i>lin-28L64s</i>-GFP activity in heart precursors (and amnioserosa cells) at stage 14 (B2, B3) and a reduced activity in cardioblasts and pericardial cells at stage 16 (B4, B5). (C2, C3) Mutation of the CEE motifs causes almost complete loss of <i>midE19s</i>-GFP activity in Tin⁺ cardioblasts (stage 16).