CHARACTERIZATION OF CARDIAC GENE CIS-REGULATORY ELEMENTS IN THE EARLY STAGES OF CHICKEN HEART MORPHOGENESIS

Abstract To study transcriptional regulation during early stages of cardiogenesis, stage 10 –17 chicken embryo hearts were transfected efficiently within the intact embryo by application of plasmid DNA complexed to liposomes. Viral regulatory sequences and the skeletal α -actin, SERCA2 and ANF promoters activated expression of reporter genes in the primitive heart tube. Deletion and mutation analysis of the skeletal α -actin promoter revealed the importance of CArG cis -regulatory elements in enhancing transcription of the gene during early heart development. These results demonstrate the utility of this method for the identification of gene regulatory elements that specify the cardiac phenotype during early stages of heart morphogenesis.