Smad4 was expressed at all developmental stages of zebrafish.
Knockdown of smad4 in embryos resulted in defects in the heart and the trunk structure.
Knockdown of smad4 in embryos downregulated the expression of two heart-chamber markers.
Knockdown of smad4 in embryos increased the expression of myogenic regulatory factors.
Knockdown of smad4 in embryos resulted in an obvious increase of cell apoptosis.