Fig. S4
Cadm4 curtails the addition of latedifferentiating cells to the OFT.
(A-F) Partial reconstructions of frontal views, arterial pole up, of Tg(myl7:kaede)- expressing hearts at 58 hpf, following photoconversion at 46 hpf. Comparison of green fluorescence (A,D) and red fluorescence (B,E) reveals the presence of latedifferentiating cells (green and not red). (A-C) Control embryos do not exhibit addition of late-differentiating cells between 46-58 hpf (n=14). (D-F) In contrast, all cadm4 morphants exhibit a population of OFT cells (arrowheads) that initiated differentiation during this timeframe (n=38/38), and many of the morphants (n=24/38) also possess a population of distal late-differentiating CMs that are not connected to the heart (arrows, F).
(G-L) Single confocal slices through Tg(myl7:EGFP);Tg(myl7:DsRedt4) hearts at 84 hpf distinguish early-differentiating and late-differentiating CMs, as in Fig. 2J-R. cadm4 morphants (J-L) still exhibit a small group of late-differentiating CMs (arrowheads), whereas control siblings (G-I) do not (ne30). Also, similar to the results seen above (DF), many of the cadm4 morphants exhibit a population of late-differentiating CMs that are not directly connected to the heart (arrows, L).
Scale bars: 50 μm.