TY - JOUR T1 - Probing the origin of matching functional jaws: roles of Dlx5/6 in cranial neural crest cells JF - bioRxiv DO - 10.1101/296665 SP - 296665 AU - Miki Shimizu AU - Nicolas Narboux-Nême AU - Yorick Gitton AU - Camille de Lombares AU - Anastasia Fontaine AU - Gladys Alfama AU - Taro Kitazawa AU - Yumiko Kawamura AU - Eglantine Heude AU - Lindsey Marshall AU - Hiroki Higashiyama AU - Youichiro Wada AU - Yukiko Kurihara AU - Hiroki Kurihara AU - Giovanni Levi Y1 - 2018/01/01 UR - http://biorxiv.org/content/early/2018/04/16/296665.abstract N2 - Gnathostome jaws derive from the first pharyngeal arch (PA1), a complex structure constituted by Neural Crest Cells (NCCs), mesodermal, ectodermal and endodermal cells. Here, to determine the regionalized morphogenetic impact of Dlx5/6 expression, we specifically target their inactivation or overexpression to NCCs. NCC-specific Dlx5/6 inactivation (NCC∆Dlx5/6) generates severely hypomorphic lower jaws that present typical maxillary traits. Therefore, differently from the symmetric jaws obtained after constitutive Dlx5/6 inactivation, NCC∆Dlx5/6 embryos present a strikingly asymmetric mouth. Reciprocally, forced Dlx5 expression in maxillary NCCs provokes the appearance of distinct mandibular characters in the upper jaw. We conclude 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 Dlx5/6 expression in NCCs and in distinct ectodermal territories. The co-evolution of synergistic anatomical structures can apparently involve the coordination of different regulations of the same genes in distant embryonic territories. ER -