The Gata4 transcription factor is essential for normal heart development, but the molecular basis for its function remain poorly understood. We profiled at the whole genome level transcript changes in cardiomyocytes when Gata4 is depleted from zebrafish embryos. Our objective was to elucidate the cardiomyocyte-specific molecular program functioning downstream of Gata4 in order to better understand the role of Gata4 in cardiac morphogenesis. Overall design: Six samples in total are deposited. Three replicate control samples and three replicate Gata4 morphant samples were analyzed.