apical ectodermal ridge
multilayered ectodermal region at the distal tip of a limb or fin bud necessary for the proper development of the underlying mesenchyme[MP,modified]. Along with the zone of polarizing activity, it is a crucial organizing region during limb development[WP]. [ http://en.wikipedia.org/wiki/Apical_ectodermal_ridge ]
Term info
apical ectodermal ridge
- apical epidermal ridge
pheno_slim
relationship loss: subclass proliferative region (TAO:0000098)[TAO]
note that media, dorsal fins etc have AERs.
http://upload.wikimedia.org/wikipedia/commons/5/56/Limbbuddiagram.jpg
Distal ectodermal thickening which forms along the anterior-posterior limb axis. Signaling from this region influences proximal-distal patterning of the limb. Structure is missing in some lineages (salamanders, Eleutherodactylus coqui) however morphologically their indistinct distal ectoderm may still be involved in signaling.[AAO], Proliferative region that is part of the developing fin fold or fin.[TAO]
maintaining mesenchyme in plastic proliferating state; maintaining expression of A-P axis genes; interacting with D-V proteins. Genes: AER induced by Fgf10 in mesenchyme. AER secretes Fgf8, which stimulates mitosis in the mesenchyme causing Fgf10 production - positive feedback loop
uberon
AER, crista ectodermalis apicalis
UBERON:0004356
The AER of tetrapods regresses after specification of skeletal progenitors, the AER of teleosts form an elongating fin fold
Term relations
- embryonic structure
- part of some paired limb/fin bud
- developmentally_induced_by some mesenchyme
- part of some ectoderm