Tbx6 is a determinant of cardiac and neural cell fate decisions in multipotent P19CL6 cells

► Role of Tbx6 in P19CL6 differentiation to cardiomyocytes and neural cells is defined. ► Tbx6 levels increase in cardiac myocyte and decrease in neural differentiation. ► Necessity and sufficiency of Tbx6 is delineated for these events. ► Our data suggest that Tbx6 may function as a switch point in this paradigm.