A maternally established SoxB1/SoxF axis is a conserved feature of chordate germ layer patterning.
Cattell MV, Garnett AT, Klymkowsky MW, Medeiros DM. A maternally established SoxB1/SoxF axis is a conserved feature of chordate germ layer patterning. Evol Dev. 2012 Jan-Feb; 14(1):104-15.