Dkk2 plays an essential role in the corneal fate of the ocular surface epithelium.

The Dkk family of secreted cysteine-rich proteins regulates Wnt/beta-catenin signaling by interacting with the Wnt co-receptor Lrp5/6. Here, we show that Dkk2-mediated repression of the Wnt/beta-catenin pathway is essential to promote differentiation of the corneal epithelial progenitor cells into a non-keratinizing stratified epithelium. Complete transformation of the corneal epithelium into a stratified epithelium that expresses epidermal-specific differentiation markers and develops appendages such as hair follicles is achieved in the absence of the Dkk2 gene function.

Generation and characterization of dickkopf3 mutant mice.

dickkopf (dkk) genes encode a small family of secreted Wnt antagonists, except for dkk3, which is divergent and whose function is poorly understood. Here, we describe the generation and characterization of dkk3 mutant mice. dkk3-deficient mice are viable and fertile.