Jaw transformation with gain of symmetry after Dlx5/Dlx6 inactivation: Mirror of the past?

@article{Beverdam2002JawTW,
  title={Jaw transformation with gain of symmetry after Dlx5/Dlx6 inactivation: Mirror of the past?},
  author={Annemiek Beverdam and Giorgio Roberto Merlo and Laura Paleari and Stefano Mantero and Francesca Genova and Ottavia Barbieri and Philippe Janvier and Giovanni Levi},
  journal={genesis},
  year={2002},
  volume={34}
}
Summary: In modern vertebrates upper and lower jaws are morphologically different. Both develop from the mandibular arch, which is colonized mostly by Hox‐free neural crest cells. Here we show that simultaneous inactivation of the murine homeobox genes Dlx5 and Dlx6 results in the transformation of the lower jaw into an upper jaw and in symmetry of the snout. This is the first homeotic‐like transformation found in this Hox‐free region after gene inactivation. A suggestive parallel comes from… 
Transitory expression of and in maxillary arch Dlx 5 Dlx 6 precursors is essential for upper jaw morphogenesis
TLDR
Using 3D reconstruction, it is shown that inactivation of and does not only affect the mandibular arch, but results in the Dlx5 DlX6 simultaneous transformation ofMandibular and maxillary skeletal elements which assume a similar morphology with gain of symmetry.
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Transitory expression of and in maxillary arch precursors is essential for upper jaw Dlx 5 Dlx 6 morphogenesis
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  • 2019
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TLDR
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  • Biology
  • 2019
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Probing the origin of matching functional jaws: roles of Dlx5/6 in cranial neural crest cells
TLDR
It is concluded that: 1) Dlx5/6 activation in NCCs invariably determines lower jaw identity; 2) the morphogenetic processes that generate functional matching jaws depend on the harmonization of Dl x5/ 6 expression in N CCs and in distinct ectodermal territories.
Jaw muscularization requires Dlx expression by cranial neural crest cells
TLDR
The genesis of jaws and their muscularization should be seen as an integrated Dlx-dependent developmental process at the origin of the vertebrate head and the role of DlX genes in defining gnathostome jaw identity could be secondary to a more primitive function in the genesis of the oral skeletomuscular system.
Craniofacial traits determined by neural crest cells-restricted expression of Dlx5/6: probing the origin of matching functional jaws
TLDR
The data demonstrate that Dlx5/6 expression in NCCs is necessary and sufficient to specify mandibular identity and these same genes must also be regulated in other cell types to generate functional matching jaws capable to support mastication.
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