spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

Right arrow Help viewing high resolution images
Right arrow Return to article
(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.


Figure 6


Fig. 6. In utero gene transfer of a Wnt inhibitor phenocopies the Tcf4-/-; Lef1-/- facial defect. (A-C) Mouse embryos were injected at E10.5 with a control adenovirus encoding lacZ then collected 24 hours later and stained for ß-gal activity. Lateral and frontal views show widespread X-Gal staining, indicating widespread, unifrom adenoviral infection in the lateral nasal (l), frontonasal (f), maxillary (mx) and mandibular (mn) prominences. (D,E) Non-injected or (F,G) Ad-Dkk1-injected embryos were collected at E13.5 (i.e. 96 hours after injection at E9.5). (D,E) Control embryos show characteristic Wnt reporter activity in the face and limb buds; note activity in the apical ectodermal ridge (aer) and skeletal condensations of the forelimb (yellow asterisks). (F,G) Ad-Dkk1 treatment truncates Wnt-dependent forelimb and digit growth (inset); note corresponding reduction in Wnt reporter activity. (H-K') Comparison between control and Ad-Dkk1-treated faces. (H,H') Control embryos exhibit normal facial morphology and undisturbed boundaries of Wnt reporter activity in the face and whisker buds. (I-K') Ad-Dkk1-treated embryos show an increasingly severe facial malformation that parallels the reduction in Wnt reporter activity. For example, the width of the frontonasal prominence is variably expanded (compare red brackets) owing to a reduction in growth of the maxillae. The more severe phenotypes correspond to the most dramatic reduction in Wnt reporter activity, so that the maxillary (mx) prominences are smaller and the frontonasal (f) is concomitantly larger. The reduction in X-Gal staining is clearly visible in Ad-Dkk1-treated whisker primordia. (L,M) Transverse sections through embryos collected at E13.5 (96 hours after injection at E9.5). Control (L, non-injected) nasal capsules show normal fusion of the facial prominences. In Ad-Dkk1-treated embryos (M), the reduction in maxillary growth is sometimes associated with facial clefting. Scale bars: white, 1 mm; black, 500 µm.





Right arrow Return to article