Expression of Frizzled genes in the developing chick eye.

Frizzleds are transmembrane receptors that can transduce signals dependent upon binding of Wnts, a large family of secreted glycoproteins homologous to the Drosophila wingless (wg) gene product and critical for a wide variety of normal and pathological developmental processes. In the nervous system, Wnts and Frizzleds play an important role in anterior-posterior patterning, cell fate decisions, proliferation, and synaptogenesis. However, little is known about the role of Frizzled signaling in the developing eye. We isolated cDNAs for ten chick Frizzleds and analyzed the spatial and temporal expression patterns during eye development in the chick embryo. Frizzled-1 to -9 are specifically expressed in the eye at various stages of development and show a complex and partially overlapping pattern of expression.