Antagonistic signals between BMP4 and FGF8 define the expression of Pitx1 and Pitx2 in mouse tooth-forming anlage. Dev Biol 2000 Jan 15;217(2):323-32
Date
01/08/2000Pubmed ID
10625557DOI
10.1006/dbio.1999.9547Scopus ID
2-s2.0-0034650899 (requires institutional sign-in at Scopus site) 176 CitationsAbstract
Members of the Pitx/RIEG family of homeodomain-containing transcription factors have been implicated in vertebrate organogenesis. In this study, we examined the expression and regulation of Pitx1 and Pitx2 during mouse tooth development. Pitx1 expression is detected in early development in a widespread pattern, in both epithelium and mesenchyme, covering the tooth-forming region in the mandible, and is then maintained in the dental epithelium from the bud stage to the late bell stage. Pitx2 expression, on the other hand, is restricted to the dental epithelium throughout odontogenesis. Interestingly, from E9.5 to E10.5, the expression domains of Pitx1 and Pitx2, in the developing mandible, overlap with that of Fgf8 but are exclusive to the zone of Bmp4 expression. Bead implantation experiments demonstrate that ectopic expression of Fgf8 can induce/maintain the expression of both Pitx1 and Pitx2 at E9.5. In contrast, Bmp4-expressing tissues and BMP4-soaked beads were able to repress Pitx1 expression in mandibular mesenchyme and Pitx2 expression in the presumptive dental epithelium, respectively. However, the effects of FGF8 and BMP4 are transient. It thus appears that the early expression patterns of Pitx1 and Pitx2 in the developing mandible are regulated by the antagonistic effects of FGF8 and BMP4 such that the Pitx1 and Pitx2 expression patterns are defined. These results indicate that the epithelial-derived signaling molecules are responsible not only for restricting specific gene expression in the dental mesenchyme, but also for defining gene expression in the dental epithelium.
Author List
St Amand TR, Zhang Y, Semina EV, Zhao X, Hu Y, Nguyen L, Murray JC, Chen YAuthor
Elena V. Semina PhD Chief, Professor in the Ophthalmology and Visual Sciences department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBone Morphogenetic Protein 4
Bone Morphogenetic Proteins
DNA-Binding Proteins
Fibroblast Growth Factor 8
Fibroblast Growth Factors
Gene Expression Regulation, Developmental
Homeodomain Proteins
MSX1 Transcription Factor
Mandible
Mice
Mutation
Nuclear Proteins
Odontogenesis
Paired Box Transcription Factors
Signal Transduction
Tissue Distribution
Tooth
Tooth Germ
Transcription Factors
