[HTML][HTML] Retinoic acid synthesis controlled by Raldh2 is required early for limb bud initiation and then later as a proximodistal signal during apical ectodermal ridge …
We present evidence for the existence of two phases of retinoic acid (RA) signaling required
for vertebrate limb development. Limb RA synthesis is under the control of retinaldehyde
dehydrogenase-2 (Raldh2) expressed in the lateral plate mesoderm, which generates a
proximodistal RA signal during limb outgrowth. We report that Raldh2-/-embryos lack trunk
mesodermal RA activity and fail to initiate forelimb development. This is associated with
deficient expression of important limb determinants Tbx5, Meis2, and dHand needed to …
for vertebrate limb development. Limb RA synthesis is under the control of retinaldehyde
dehydrogenase-2 (Raldh2) expressed in the lateral plate mesoderm, which generates a
proximodistal RA signal during limb outgrowth. We report that Raldh2-/-embryos lack trunk
mesodermal RA activity and fail to initiate forelimb development. This is associated with
deficient expression of important limb determinants Tbx5, Meis2, and dHand needed to …
