(A) In E15.5 Wnt1-Cre; Zsgreenfl/fl mouse heart, cardiac neural crest progenies were distributed in the outflow tract, valves and myocardium of both ventricles. Density of Zsgreen+ cells decreased along the proximal-to-distal axis, thus no cell contributed to the apex (Wnt1-Zsgreen, green; Troponin T, red; DAPI, blue). (B) Proliferation marker PH3 did not selectively colocalize with Zsgreen+ cells (PH3, magenta; B’, separate channels for colocalization). (C) Apoptosis marker Caspase3 was not selectively expressed in Zsgreen+ cells (Caspase 3, magenta; C’, separate channels for colocalization). (D) Cardiac neural crest did not contribute to apical myocardium in Wnt1-Cre; Zsgreenfl/fl mouse (Wnt1-Zsgreen, green; Troponin T, red; DAPI, blue), or (E) Wnt1-Cre; R26mtmg mouse (Wnt1-membrane GFP, green; membrane Tomato, red; DAPI, blue). (F–H) On postnatal day 2, cardiac neural crest progenies in Wnt1-ZsGreen mouse persisted in the myocardium of the ventricle (F). (separate channels in F’), outflow tract (G), but not the apex (H) (Wnt1-Zsgreen, green; Troponin T, red; DAPI, blue), similar to what was observed in E15.5 hearts. Scale bars: A 400 μm; B, C, F, G 100 μm; D, E, H 160 μm.