Lef1 expression is activated by BMP-4 and regulates inductive tissue interactions in tooth and hair development.
Targeted inactivation of the murine gene encoding the transcription factor LEF-1 abrogates the formation of organs that depend on epithelial-mesenchymal tissue interactions. In this study we have recombined epithelial and mesenchymal tissues from normal and LEF-1-deficient embryos at different stages of development to define the LEF-1-dependent steps in tooth and whisker organogenesis. At the initiation of organ development, formation of the epithelial primordium of the whisker but not tooth is dependent on mesenchymal Lef1 gene expression. Subsequent formation of a whisker and tooth mesenchymal papilla and completion of organogenesis require transient expression of Lef1 in the epithelium. These experiments indicate that the effect of Lef1 expression is transmitted from one tissue to the other. In addition, the finding that the expression of Lef1 can be activated by bone morphogenetic protein 4 (BMP-4) suggests a regulatory role of this transcription factor in BMP-mediated inductive tissue interactions.
Kratochwil
K
K
Howard Hughes Medical Institute, University of California, San Francisco, 94143, USA.
Dull
M
M
Farinas
I
I
Galceran
J
J
Grosschedl
R
R
D000818:Animals; D019485:Bone Morphogenetic Proteins; D002454:Cell Differentiation; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D000078404:Epidermal Cells; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006197:Hair / Q000196:embryology*; D051821:Lymphoid Enhancer-Binding Factor 1; D051379:Mice; D008817:Mice, Mutant Strains; D011506:Proteins / Q000502:physiology*; D014070:Tooth / Q000196:embryology*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D019485:Bone Morphogenetic Proteins; D004268:DNA-Binding Proteins; C497574:Lef1 protein, mouse; D051821:Lymphoid Enhancer-Binding Factor 1; D011506:Proteins; D014157:Transcription Factors