The structural development of the heart depends heavily on mechanical forces, and rhythmic contractions generate essential physical stimuli during morphogenesis. Cardiac cells play a critical role in coordinating this process by sensing and responding to these mechanical forces. In vivo, cells experience rhythmic spatial and temporal variations in deformation-related stresses throughout heart development. What impact do these mechanical forces have on heart morphogenesis? Recent work in zebrafish (Danio rerio) offers important insights into this question. This review focuses on endocardial (EdCs) and myocardial cells (cardiomyocytes, CMs), key cell types in the heart, and provides a comprehensive overview of forces and tissue mechanics in zebrafish and their direct influence on cardiac cell identity.

Declaration of interests The authors declare no competing interests.