XB-IMG-85168
Xenbase Image ID: 85168
|
Fig. 4. Fgf8 regulates the expression of FoxG1, Ras-dva1, Xag and Xagr2.
(A-D) Injections of Fgf8a mRNA elicit ectopic expression of FoxG1, Ras-dva1, Xag and Xagr2 in the anterior ectoderm of the midneurula stage embryos. Fgf8a mRNA mixed with FLD tracer was injected at concentration of 20 pg/blastomere in a pair of adjacent animal dorsal and ventral blastomeres on the left sides of 16- to 32-cell stage embryos. Whole-mount in situ hybridization was performed at the midneurula stage. Anterior view with the dorsal side upward. (A′-D′) Overlays of the white light and fluorescent images of embryos shown in panels A-D. Red arrowheads in panels A and C indicate the borders of ectopic expression, which correspond to the borders of cell clones with strong fluorescence. (E-H) Vibratome sections of embryos injected with Fgf8a mRNA. Note that whereas Ras-dva1, Xag and Xagr2 are activated only in the outer layer of the ectoderm (E-G, overlays of bright light and fluorescent images), ectopic FoxG1 is induced exclusively in the inner layer (H,H′). (I-L) Injection of Fgf8a MO leads to inhibition of FoxG1, Ras-dva1, Xag and Xagr2 expression. An Fgf8a MO (1-2 pmol/blastomere) was injected with a FLD tracer in a pair of adjacent animal dorsal and ventral blastomeres on the left sides of 16- to 32-cell stage embryos. (M,N) Co-injection of Fgf8 mRNA is unable to rescue inhibition of Xag and Xagr2 expression elicited by Ras-dva1 MO. The black arrowheads indicate sites of expression inhibition. Image published in: Tereshina MB et al. (2014) © 2014. This image is reproduced with permission of the journal and the copyright holder. This is an open-access article distributed under the terms of the Creative Commons Attribution license Larger Image Printer Friendly View |