The preplacodal region: an ectodermal domain with multipotential progenitors that contribute to sense organs and cranial sensory ganglia

Int J Dev Biol. 2007;51(6-7):447-61. doi: 10.1387/ijdb.072327as.


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.

Publication types

  • Review

MeSH terms

  • Animals
  • Body Patterning
  • Chick Embryo
  • Ectoderm / physiology*
  • Embryo, Nonmammalian / anatomy & histology
  • Embryo, Nonmammalian / physiology
  • Embryonic Induction
  • Fibroblast Growth Factors / genetics
  • Fibroblast Growth Factors / metabolism
  • Forecasting
  • Ganglia, Sensory / anatomy & histology*
  • Ganglia, Sensory / embryology
  • Ganglia, Sensory / physiology*
  • Gene Expression Regulation, Developmental
  • Head / embryology*
  • Models, Biological
  • Sense Organs / anatomy & histology
  • Sense Organs / embryology
  • Sense Organs / physiology*
  • Signal Transduction / physiology
  • Wnt Proteins / genetics
  • Wnt Proteins / metabolism


  • Wnt Proteins
  • Fibroblast Growth Factors