Dr. Todd Evans
Professor of Cell and Developmental Biology in Surgery Weill Cornell Medical College, Cornell University
Host: Dr. I. Scott
May 5th @ 2PM
1 King’s College Circle, Medical Sciences Building, Room 4171

Three highly related genes, Gata4, Gata5, and Gata6, encode transcription factors that regulate essentially every aspect of cardiac biology, from generation of precardiac mesoderm, specification and differentiation of endocardial, epicardial, and myocardial progenitors, heart tube formation, growth and morphogenesis, septation and valve formation, cardio-protection and hypertrophy, and regeneration. How the three genes regulate the spatial, temporal, and tissue-specific genetic and epigenetic networks that underlie all of these disparate programs is poorly understood. Furthermore, mutations in each of the genes have individually been associated with human cardiomyopathies, including atrial and ventricular septal defects, tetralogy of Fallot, bicuspid aortic valve syndrome, and familial dilated cardiomyopathy. Other transcription factor genes, and some terminal differentiation markers are known to be regulated by these genes, but the key target genes that control intermediary functions such as lineage specification, growth, and morphogenesis are not known. We carried out screens in zebrafish to find such genes, and discovered previously unrecognized mediators of cardiac specification and myocardial function. In addition, an epigenetic program was found to be essential for development of the epicardium. Discovery of genes controlled by GATA factors is proving to be a productive strategy for finding new important regulators of cardiac biology.