Hedgehog signaling is required for differentiation of endocardial progenitors in zebrafish

► Hedgehog signaling is required for endocardial specification and differentiation. ► Hh induces fibronectin expression in the endocardial progenitors. ► Endoderm is required for endocardial migration but is dispensable for differentiation. ► Hh signal is received cell autonomously by the endocardial progenitors.