Autonomous and non-cell autonomous role of cilia in structural birth defects in mice
Fig 10
Hyperplasia of maxillary and mandibular prominences resulting in bone fusions with Wnt1-Cre deletion of Ift-140.
(A–C) E12.5 control (Ift140flox/+, Wnt1-Cre+ or Wnt1-Cre-) (A, B) and experimental animals (Ift140flox/null1, Wnt1-Cre+) (C). Overgrowth of the maxillary and mandibular processes (yellow outline, bottom row) is apparent in the mutant animals (C). The maxillary overgrowth is concealing the eye. (D–O) E18.5 control (D–F, J–L) and experimental animals (G–I, M–O). The Wnt1-Cre Ift140flox/null1 mutant skull and face is shortened, and smaller (G–I) than the Ift140flox/+ Wnt1-Cre+ control embryos (D–F), and have several defects in neural crest-derived bones. Laterally, the temporomandibular joint is absent resulting in the fusion between the maxilla and mandible in the experiment animals (G, L arrows). In the bird’s eye view of the skull, there are ectopic boney islands present in the mutant frontal bones (arrowhead, H), suggestive of a problem with cell migration. Remarkably, the eyes are visible in this view but are below the frontal bones and medial to the maxilla (H, arrows). The palatal view shows that the maxillary bones are displaced laterally (I, open arrowhead), the vomer is present (I, arrowhead) and the anterior, neural crest-derived cranial base is absent (I, arrows). (J–O) The mandible is missing its 3 processes (arrowhead, L). The alveolar ridge for the molars is present, but is smaller (arrowhead, M).