The convergence of Notch and MAPK signaling specifies the blood progenitor fate in the Drosophila mesoderm

► Analysis of the origin and morphogenesis of the cardiogenic mesoderm in Drosophila. ► Delta required for specification of blood cell fate in hemangioblast progenitors. ► Dl expressed in early cardiogenic clusters but becomes restricted to cardioblasts. ► MAPK activity required for maintenance of Dl and cardiogenic mesoderm survival.