The left ventricle cardiac progenitors are mainly derived from the primary heart field, and the right ventricle cardiomyocytes are from the secondary heart field [8].
Cardiac morphogenesis and maturation require the deployment of multiple cell lineages that are derived from the primary heart field, secondary heart field, and neural crest cells [4 6].
Interfering with cardiac progenitor recruitment from the secondary heart field resulted in a small right ventricle.
Thus, it was impossible to affect cardiac progenitor recruitment from the secondary heart field because MLC2a was expressed in differentiated cardiomyocytes instead of in cardiac progenitors of the secondary heart field.
The transfected cells begin beating even before the endogenous heart field starts to form (Takeuchi and Bruneau, 2009).
Subsequently, the primary heart tube is elongated by recruiting cells that are generated from the second heart field.
Insulin gene enhancer protein-1 (Isl-1) is expressed in the entire secondary heart field and then in the bilateral pharyngeal mesoderm.
Initially, the cardiac progenitors that derive from the primary heart field migrate toward the midline of the embryo to fuse and form the primary heart tube.
If we are interested in explaining how hearts (phenomena) develop, then we might investigate the molecular or cellular mechanisms occurring in the heart field during zebrafish ontogeny.
The cardiac cells were all traced back to two original sources of MCPs, namely first heart field (FHF) and second heart field (SHF) progenitors, with an additional contribution of neural crest cells (Fig. 3) (Bondue et al., 2011; Buckingham and Desplan, 2010).
Hes1 is expressed in pharyngeal endoderm and mesoderm including the second heart field.
