Fig. 3
RA restricts the size of the FHF and maintains the SHF progenitor population in nls mutant embryos. (A, B) IHC for Nkx2.5 (purple) and Mhc (green) in WT sibling and nls mutant embryos at the 20s stage (19 hpf). Nls mutant hearts were sometimes delayed in forming the cardiac cone relative to WT siblings. Views are dorsal with anterior up. Scale bar – 100 μm. (C) Quantification of the number of Nkx2.5+/Mhc+ and Nkx2.5+/Mhc-cells in WT sibling and nls mutant embryos at the 20s stage (19 hpf). ∗∗∗∗ indicates p < 0.0001. ns – not significant. (D) Percentage of Nkx2.5+/Mhc+ and Nkx2.5+/Mhc-cells within the hearts of WT sibling and nls mutant embryos at the 20s stage (19 hpf). (E, F) IHC for Nkx2.5 (purple) and Mhc (green) in WT sibling and nls mutant embryos at 24 hpf. Frontal views with the arterial pole up. Arrows indicate the border between Nkx2.5+/Mhc+ and Nkx2.5+/Mhc-cells. Scale bar – 100 μm. (G) Quantification of the number of Nkx2.5+/Mhc+ and Nkx2.5+/Mhc-cells in WT sibling and nls mutant embryos at 24 hpf. ∗ indicates p = 0.0253, ∗∗ indicates p = 0.0026, ∗∗∗∗ indicates p < 0.0001. (H) Percentage of Nkx2.5+/Mhc+ and Nkx2.5+/Mhc-cells within the hearts of WT sibling and nls mutant embryos at 24 hpf. |
Reprinted from Developmental Biology, 473, Duong, T.B., Holowiecki, A., Waxman, J.S., Retinoic acid signaling restricts the size of the first heart field within the anterior lateral plate mesoderm, 119-129, Copyright (2021) with permission from Elsevier. Full text @ Dev. Biol.