Role of Hopx in myogenesis and commitment [HopxKO+Wnt]

Progenitor cells require coordinated expression of lineage-specific genes to regulate differentiation into daughter cell types. Hopx labels cardiac progenitors that are commited to the cardiac myocyte lineage. Hopx-deficiency leads to thin myocardium in approximately mid-gestation lethality in approximately 50% of embryos (secondary to thin myocardium and presumed cardiac rupture). Hopx-/- EBs display impaired myogenesis during cardiac differentiation. ChIP-seq and RNA expression analysis suggests that Hopx down regulates Wnt signaling by directly occupying and repressing wnt ligand genes. Analysis of embryoid bodies on day 8 of cardiac differentiation. RNA was made of from Hopx +/- embryoid bodies or Hopx -/- embryoid bodies treated with 12.5 uM XAV939. Heterozygous embryoid bodies included 0 uM XAV939, a well-characterized, known Wnt inhibitor. Embryonic stem cell lines were derived from littermate mouse blastocysts. Results provide insight into gene programs regulated by Hopx in cardiac development. Three biological replicates of Hopx-/- + 12.5 uM XAV939 vs 3 biological replicates of Hopx+/- embryoid bodies, day 8 of cardiac differentiation.