Requirement of normal Foxf1 function for lateral plate differentiation and coelom formation. Differentiation of somatopleure and splanchnopleure and the associated formation of the coelomic cavity is disturbed in Foxf1−/− embryos. a, c Wildtype, b, dFoxf1−/− embryo at mouse embryonic day 8.5. Separation of the somatic and splanchnic mesodermal layers is incomplete in the Foxf1−/− embryo, and formation of the coelomic cavity is disrupted, with failure of the coelomic cavity to invade the lateral plate mesoderm. nt neural tube, da dorsal aorta, co coelom, am amnion, so somatic mesoderm or somatopleure, sp splanchnic mesoderm or splanchnopleure. Reproduced from Ref. [6], Figure 8, page 163, with permission