The preplacodal region: an ectodermal domain with multipotential progenitors that contribute to sense organs and cranial sensory ganglia.
The otic primordium belongs to a group of related structures, the sensory placodes that contribute to the paired sense organs - ear, eye and olfactory epithelium - and to the distal parts of the cranial sensory ganglia. Recent evidence suggests that despite their diversity, all placodes share a common developmental origin and a common molecular mechanism which initiates their formation. At the base of placode induction lies the specification of a unique "placode field", termed the preplacodal region and acquisition of this "preplacodal state" is required for ectodermal cells to undergo otic development. Here I review the molecular mechanisms that sequentially subdivide the ectoderm to give rise to the placode territory.
Streit
Andrea
A
Department of Craniofacial Development, King's College London, Guy's Campus, London, UK. andrea.streit@kcl.ac.uk
D000818:Animals; D019521:Body Patterning; D002642:Chick Embryo; D004475:Ectoderm / Q000502:physiology*; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000502:physiology; D004627:Embryonic Induction; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism; D005544:Forecasting; D017950:Ganglia, Sensory / Q000033:anatomy & histology* / Q000196:embryology / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D006257:Head / Q000196:embryology*; D008954:Models, Biological; D012679:Sense Organs / Q000033:anatomy & histology / Q000196:embryology / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism
D051153:Wnt Proteins; D005346:Fibroblast Growth Factors