Document Type

Article

Publication Date

2005

Publication Title

Developmental Dynamics

Volume

234

Issue

3

First Page

577

Last Page

589

DOI

10.1002/dvdy.20540

Keywords

lens placode, Pitx, Xenopus laevis, pituitary gland, retina, Pax6, Rx, Six3, Lens1, beta-crystallin, Otx2, laterality, morpholino oligonucleotide

Abstract

Pitx3 is expressed in tissues fated to contribute to eye development, namely, neurula stage ectoderm and prechordal mesoderm, then presumptive lens ectoderm, placode, and finally lens. Pitx3 overexpression alters lens, optic cup, optic nerve, and diencephalon development. Many of the induced anomalies are attributable to midline deficits; however, as assessed by molecular markers, ectopic Pitx3 appears to temporarily enlarge the lens field. These changes are usually insufficient to generate either ectopic lenses to enlarge the eye that eventually differentiates. Conversely, use of a repressor chimera or of antisense morpholinos alters early expression of marker genes, and later inhibits lens development, thereby abrogating retinal induction. Reciprocal grafting experiments using wild-type and morpholino-treated tissues demonstrate that Pitx3 expression in the presumptive lens ectoderm is required for lens formation. Contradictory to recent assertions that retina can form in the absence of a lens, the expression of Pitx3 in the presumptive lens ectoderm. is critical for retina development.

Comments

This is the accepted version of the following article:Lens and Retina Formation Require Expression of Pitx3 in Xenopus Pre-lens Ectoderm, which has been published in final form at http://dx.doi.org/10.1002/dvdy.20540

Included in

Biology Commons

Share

COinS