Our histological analysis suggests that Bptf mutants are defective in establishing an A-P axis. Apparent defects in A-P axis can be due to defects in the establishment or migration of the DVE [29]. To monitor the development of the DVE and its transition to the AVE, we analyzed the markers Otx2, Lefty1, Cer1, Hesx1, Hex1, Gata6, Nanog and Nodal by in situ hybridization in E4.5 to E6.5 mutant embryos [32]–[37].
