title: Modulation of WNT signaling activity is key to the formation of the embryonic head.
abstract: The formation of the embryonic head begins with the assembly of the progenitor tissues of the brain, the head and face primordia and the foregut that are derived from the primary germ layers during gastrulation. Specification of the anterior-posterior polarity of major body parts and the morphogenesis of the head and brain specifically is driven by inductive signals including those mediated by BMP, Nodal, FGF and WNT. A critical role of β-catenin dependent WNT signalling activity for head morphogenesis has been revealed through the analysis of the phenotypic impact of loss of function mutation of an antagonist: DKK1, a transcriptional repressor: GSC; and the outcome of interaction of Dkk1 with genes coding three components of the canonical signalling pathway: the ligand WNT3, the co-receptor LRP6 and the transcriptional co-factor, β-catenin. The findings highlight the requirement of a stringent control of the timing, domain and level of canonical WNT signalling activity for the formation of the embryonic head.
authors.affiliation: Embryology Unit, Children's Medical Research Institute, University of Sydney, Westmead, Australia.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Fossat
authors.forename: Vanessa
authors.initials: V
authors.lastname: Jones
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Garcia-Garcia
authors.forename: Patrick P L
authors.initials: PP
authors.lastname: Tam
mesh_terms: D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D004622:Embryo, Mammalian / Q000196:embryology; D047108:Embryonic Development; D005346:Fibroblast Growth Factors / Q000378:metabolism; D006257:Head / Q000196:embryology*; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D051379:Mice; D055457:Nodal Protein / Q000378:metabolism; D015398:Signal Transduction; D051153:Wnt Proteins / Q000378:metabolism*; D051176:beta Catenin / Q000378:metabolism
chemical_list: D019485:Bone Morphogenetic Proteins; C501127:Dkk1 protein, mouse; D036341:Intercellular Signaling Peptides and Proteins; D055457:Nodal Protein; D051153:Wnt Proteins; D051176:beta Catenin; D005346:Fibroblast Growth Factors