Expression of Limks in ocular tissues during eyelid closure.

In situ hybridization in E15.5 specimens with radioactive riboprobes (as = antisense; s  =  sense) specific for either Limk2 or Limk1. (A) High levels of Limk2 are detected in the epithelium (ep) in both upper and lower eyelids in wild type mice (+/+). The epithelium in the cornea (c) and differentiated cells in the ganglion cell layer (gcl) of the retina express Limk2. The emerging epithelial sheets at the eyelid tips (arrows) exhibit more intense Limk2 hybridization signals compared to adjacent epithelium. (B) Although the intensity of hybridization is decreased in the heterozygous (+/−) specimen, the distribution of Limk2 is comparable to that in wild type. Higher levels of Limk2 are present in the emerging epithelial sheets (arrows). (C) Homozygous mice, mounted and processed on the same slide as the specimens in A and B, show extremely low levels of hybridization. Three adjacent sections of another wild type E15.5 specimen hybridized with either the antisense Limk2 (D), antisense Limk1 (E) or sense Limk1 (F). Limk2 is expressed in the epithelium and gcl, whereas Limk1 is detectable in the gcl. The intense signal in the retinal pigment epithelium (rpe in C and F) is an artifact of melanin that appears during dark field illumination and is present in all samples shown. Scale bar  = 100 μm.