Interactions between Cdx genes and retinoic acid modulate early cardiogenesis.

Cdx transcription factors regulate embryonic positional identities and have crucial roles in anteroposterior patterning (AP) processes of all three germ layers. Previously we have shown that the zebrafish homologues cdx1a and cdx4 redundantly regulate posterior mesodermal derivatives inducing embryonic blood cell fate specification and patterning of the embryonic kidney. Here we hypothesize that cdx factors restrict formation of anterior mesodermal derivatives such as cardiac cells by imposing posterior identity to developing mesodermal cells.