Astrid Vogel

TL;DR: The data suggest a simple mechanism whereby FGF-4 links growth and pattern formation during limb development, and suggests that polarizing activity plays a role in patterning along the proximodistal axis, in addition to its well-established role in anteroposterior patterning.

TL;DR: The posterior apical ectodermal ridge is removed and it is shown that the decrease in polarizing activity of posterior cells of wing buds that normally follows ridge removal can be prevented by implanting a FGF-4-soaked bead.

TL;DR: This work examined systematically the ability of chick limb bud stumps to regenerate distal structures when fibroblast growth factor (FGF)-4 is applied and found that outgrowth of stump tissues occurred and a virtually complete skeleton developed.

TL;DR: It is found that expression of Msx-1, Hoxd-13, and Bmp-2 in posterior limb bud mesenchyme is dependent on a local signal from the apical ectodermal ridge and the addition of FGF to cultured anterior limb bud cells maintains their ability to respond to positional cues when grafted back into limb buds.

TL;DR: The apical ectodermal ridge plays a central role in limb development through its interactions with the underlying mesenchyme, and functions to maintain the activity of the polarizing region, which is thought to provide the primary signal for patterning along the antero‐posterior axis.