The mammalian heart originates from two anatomically and molecularly distinct populations of cardiac progenitor cells (CPCs) known as the first and second heart fields (FHF and SHF respectively), each of which contributes to different structures of the developed heart. Disruption of heart field development underlies several common forms of inherited and congenital heart disease (CHD), which represent a major cardiovascular health burden. However, it remains unknown how the two heart fields are specified, a fundamental step toward understanding heart malformation.
Our lab has extensively studied the role of numerous signaling molecules and pathways in CPC induction, maintenance, and specification, including Bmp, Wnt, Notch, and Numb. In particular, we found that FHF is induced by Bmp signaling, while SHF is induced by activation of canonical Wnt signaling (right). These signals in turn may be titrated by cross-talk with other pathways.