Transcriptional pathways direct cardiac development and regeneration.

Elegant studies using gene disruption strategies have defined a set of genes that are essential for normal cardiac development. Although these studies have provided a framework for the molecular regulation of cardiac morphogenesis, the genetic program of the cardiac progenitors has been incompletely defined. We used a transgenic strategy to specifically target the cardiac progenitors early during cardiac morphogenesis. With the use of flow cytometry and transcriptome analysis, we comprehensively defined the molecular program of the cardiac progenitors at distinct developmental stages. Definition of the molecular cardiac program early during development may be useful in the identification of cardiac progenitors that are resident in the adult heart. These emerging technologies will be further used to define common and distinct regulatory pathways of cardiac progenitors in the developing and regenerating heart.