mortality/aging
• newborn homozygotes die within a few hours after birth
|
craniofacial
• at E14.0, mutant skulls show absence of the processus alaris
|
• at E14.0, the pterygoid process is severely malformed
|
• at E14.0, the alveolar ridges, which normally surround molars and incisors, are missing in both jaws
|
absent molars
(
J:49857
)
• at E13.5, the dental epithelia have invaginated to form epithelial buds, but the condensation of mesenchymal cells around the bud is less prominent, despite normal tooth development up to E12.5
• at E14.5, tooth development has reached the cap stage in wild-type embryos but never proceeds beyond the bud stage in mutant embryos
|
absent teeth
(
J:49857
)
• newborn homozygotes exhibit absence of all teeth in both jaws
|
• at E13.5, the mandibular arch facing the palatal shelves is abnormally shaped
|
• at E14.0, the coronoid process, a dorsal extension of the mandible, is absent
|
• at E14.0, in a few cases (3/26), Reicherts cartilage is present but abnormally elongated and fused to the hyoid bone
|
• at E14.0, Reicherts cartilage is absent in most cases
|
• at E13.5, the shelves of mutant embryos revealed an abnormally broadened shape and lacked characteristic indentations at their ventrolateral sides
|
• at birth, all homozygotes exhibit a cleft secondary palate
• both maxillary and palatine regions are cleft, allowing direct view to the vomer and the presphenoid
|
• in some embryos, shelf elevation occurs only on one side
|
embryo
• at E11.5, development of the third and fourth pharyngeal pouches is retarded
• at E14.5, the third and fourth pouches fail to separate as epithelial buds to form the early rudiments of thymus, parathyroid, and ultimobranchial bodies
• in contrast, no developmental abnormalities are observed in the derivatives of the first and second pouches
|
• at E14.5, ultimobranchial bodies, which are derived from the fourth pouches, are absent
|
endocrine/exocrine glands
• at E14.5, ultimobranchial bodies, which are derived from the fourth pouches, are absent
|
• at E14.5, the primordia of parathyroid glands, which are derivatives of the third pharyngeal pouches, are absent
|
• at E14.5, the primordia of thymus, which are derivatives of the third pharyngeal pouches, are absent
|
hearing/vestibular/ear
• in most cases, the tympanic ring is greatly reduced in size at E14.0
|
immune system
• at E14.5, the primordia of thymus, which are derivatives of the third pharyngeal pouches, are absent
|
limbs/digits/tail
• in the lower leg of newborns, the musculus flexor digitorum, the flexor of the second to fifth toes, is absent
• however, no abnormalities are detectable in the musculature of forelimbs
|
polydactyly
(
J:49857
)
• newborn homozygotes display preaxial digit duplications in both fore- and hindlimbs
• in the hindlimb, duplication of the first digit is associated with an enlarged cartilaginous area in the region of anterior metatarsals, which appear broadened and fused, while the ossification center of the first phalange is severely reduced in the first toe
|
• in the forelimb, an extra-formed digit is not separated from the thumb
|
• external limb malformations are first noted at ~E13.5, as a thickening of the anterior-proximal limb mesenchyme
• additional mesenchyme is formed in the anterior limb region, which later differentiates into supernumerary digits and ectopic cartilage in the middle hand or foot
|
muscle
• in the lower leg of newborns, the musculus flexor digitorum, the flexor of the second to fifth toes, is absent
• however, no abnormalities are detectable in the musculature of forelimbs
|
• one of the three tendons of the musculus flexor digitorum is absent
|
respiratory system
• in E14.0 laryngeal cartilages, both the greater and the lesser horns of the hyoid bone are malformed
|
• at E14.0, the thyroid cartilage appears broadened and lacks two processes normally connecting thyroid and cricoid cartilage
|
• newborn homozygotes display gasping, develop a bloated abdomen and die shortly thereafter
|
skeleton
• at E14.0, mutant skulls show absence of the processus alaris
|
• at E14.0, the pterygoid process is severely malformed
|
• at E14.0, the alveolar ridges, which normally surround molars and incisors, are missing in both jaws
|
absent molars
(
J:49857
)
• at E13.5, the dental epithelia have invaginated to form epithelial buds, but the condensation of mesenchymal cells around the bud is less prominent, despite normal tooth development up to E12.5
• at E14.5, tooth development has reached the cap stage in wild-type embryos but never proceeds beyond the bud stage in mutant embryos
|
absent teeth
(
J:49857
)
• newborn homozygotes exhibit absence of all teeth in both jaws
|
• at E13.5, the mandibular arch facing the palatal shelves is abnormally shaped
|
• at E14.0, the coronoid process, a dorsal extension of the mandible, is absent
|
• at E14.0, in a few cases (3/26), Reicherts cartilage is present but abnormally elongated and fused to the hyoid bone
|
• at E14.0, Reicherts cartilage is absent in most cases
|
• one of the three tendons of the musculus flexor digitorum is absent
|
• in E14.0 laryngeal cartilages, both the greater and the lesser horns of the hyoid bone are malformed
|
• at E14.0, the thyroid cartilage appears broadened and lacks two processes normally connecting thyroid and cricoid cartilage
|
hematopoietic system
• at E14.5, the primordia of thymus, which are derivatives of the third pharyngeal pouches, are absent
|
digestive/alimentary system
• at E13.5, the shelves of mutant embryos revealed an abnormally broadened shape and lacked characteristic indentations at their ventrolateral sides
|
• at birth, all homozygotes exhibit a cleft secondary palate
• both maxillary and palatine regions are cleft, allowing direct view to the vomer and the presphenoid
|
• in some embryos, shelf elevation occurs only on one side
|
growth/size/body
• at E14.0, the alveolar ridges, which normally surround molars and incisors, are missing in both jaws
|
absent molars
(
J:49857
)
• at E13.5, the dental epithelia have invaginated to form epithelial buds, but the condensation of mesenchymal cells around the bud is less prominent, despite normal tooth development up to E12.5
• at E14.5, tooth development has reached the cap stage in wild-type embryos but never proceeds beyond the bud stage in mutant embryos
|
absent teeth
(
J:49857
)
• newborn homozygotes exhibit absence of all teeth in both jaws
|
• at E13.5, the shelves of mutant embryos revealed an abnormally broadened shape and lacked characteristic indentations at their ventrolateral sides
|
• at birth, all homozygotes exhibit a cleft secondary palate
• both maxillary and palatine regions are cleft, allowing direct view to the vomer and the presphenoid
|
• in some embryos, shelf elevation occurs only on one side
|