A thickened portion of ectoderm which serves as the precursor to the lens. SOX2 and Pou2f1 are involved in its development[WP]. [ http://en.wikipedia.org/wiki/Lens_placode http://zfin.org/curator ]

This is just here as a test because I lose it

Term information

database cross reference

uberon_slim, efo_slim, pheno_slim, vertebrate_core

plural term
lens placodes [ ZFA:0000122 ]

depicted by


development notes

Classical transplantation experiments using amphibian embryos suggested that the optic vesicle is the source of lens-inducing signals sufficient to generate lens tissues in competent ectoderm (reviewed in Grainger et al., 1996). More recent findings suggest a multistep model for lens induction. There is now good evidence that lens specification occurs at the neurula stage, before the optic vesicle contact the surface ectoderm, and that neural crest cell migration in the frontonasal region is required to restrict the position of the lens placode (Bailey et al., 2006)

external definition

Ectodermal primordium of the lens of the eye. Kimmel et al, 1995.[TAO]

has related synonym

placoda lentis

lens placodes

homology notes

(...) an essentially similar sequence of events occurs during the embryonic development of the vertebrate eye. The eye initially develops as a single median evagination of the diencephalon that soon bifurcates to form the paired optic vesicles. As each optic vesicle grows towards the body surface, its proximal part narrows as the optic stalk, and its distal part invaginates to form a two-layered optic cup. (...) The optic cup induces the overlying surface ectoderm first to thicken as a lens placode and then to invaginate and form a lens vesicle that differentiates into the lens.[well established][VHOG]