Morphogenetic roles of retinoic acid.
We integrated our information on morphogenetic roles of retinoic acid, focusing on development of chick limb. Retinoic acid has been considered to be a putative morphogen released from the ZPA. However, since exogenous retinoic acid induces expression of RAR beta, but not grafted ZPA, the ZPA is unlikely to produce retinoic acid. From the result that retinoic acid-treated cells induce digit duplication, retinoic acid converts anterior cells into ZPA cells. We found that retinoic acid also induces expression of homeobox genes indirectly and that bFGF enhances expression of the homeobox genes. Thus, we considered that retinoic acid and growth factors cooperate with each other to activate homeobox genes. A morphogenetic role of retinoic acid is to coordinate developmental stage of each cells by controlling expression of homeobox genes.
Noji
S
S
Department of Biochemistry, Okayama University Dental School, Japan.
Nohno
T
T
Koyama
E
E
Ide
H
H
Taniguchi
S
S
Saito
T
T
D000818:Animals; D016764:Cell Polarity / Q000502:physiology; D002478:Cells, Cultured; D005314:Embryonic and Fetal Development / Q000502:physiology; D005121:Extremities / Q000196:embryology; D005786:Gene Expression Regulation / Q000187:drug effects; D005801:Genes, Homeobox; D006801:Humans; D009024:Morphogenesis / Q000502:physiology; D014212:Tretinoin / Q000378:metabolism* / Q000494:pharmacology
D014212:Tretinoin