Optic cup and facial patterning defects in ocular ectoderm β-catenin gain-of-function mice

• Main Authors: Lang Richard A, Taketo M Mark, Smith April N, Miller Leigh-Anne D
• Format: Article
• Language: English
• Published: BMC 2006-03-01
• Series: BMC Developmental Biology
• Online Access: http://www.biomedcentral.com/1471-213X/6/14

<p>Abstract</p> <p>Background</p> <p>The canonical <it>Wnt </it>signaling pathway has a number of critical functions during embryonic development and, when activated aberrantly, in the genesis of cancer. Current evidence suggests that during eye development, regulation of Wnt signaling is critical for patterning the surface ectoderm that will contribute to multiple components of the eye. <it>Wnt </it>signaling loss-of-function experiments show that a region of periocular ectoderm will form ectopic lentoid bodies unless the <it>Wnt </it>pathway modifies its fate towards other structures. Consistent with this, <it>Wnt </it>signaling gain of function in the ocular region ectoderm results in a suppression of lens fate.</p> <p>Results</p> <p>Here we demonstrate that ectoderm-specific <it>Wnt </it>signaling gain-of-function embryos exhibit additional defects besides those noted in the lens. There are profound facial defects including a foreshortened snout, malformation of the nasal region, and clefting of the epidermis along the ocular-nasal axis. Furthermore, despite the restriction of <it>Wnt </it>pathway gain-of-function to the surface ectoderm, the optic cup is inappropriately patterned and ultimately forms a highly convoluted, disorganized array of epithelium with the characteristics of retina and retinal pigmented epithelium.</p> <p>Conclusion</p> <p>We suggest that activation of the <it>Wnt </it>pathway in surface ectoderm may disrupt the normal exchange of signals between the presumptive lens and retina that coordinate development of a functional eye.</p>