Development, Vol 108, Issue 4 717-726, Copyright © 1990 by Company of Biologists

JOURNAL ARTICLES

Transcription of a mutant collagen I gene is a cell type and stage-specific marker for odontoblast and osteoblast differentiation

M Schwarz, K Harbers and K Kratochwil
Institute of Molecular Biology, Austrian Academy of Sciences, Salzburg.

The Mov13 allele of the mouse alpha 1(I) collagen gene carries a retroviral insert in its first intron and had been reported to be transcriptionally silent. We have recently shown, however, that this mutant gene is expressed in odontoblasts of transplanted teeth derived from homozygous and heterozygous carrier embryos. The expression of the Mov13 allele has now been followed throughout in vivo development of mandibular teeth and bone in heterozygous animals, by in situ hybridization with a probe that specifically recognizes transcripts of the mutant gene. We show that the onset of its transcription precisely coincides with the final differentiation of odontoblasts and the onset of dentinogenesis, i.e. on day E16 for the incisor and at birth for the first molar. The mutant allele is also transcribed in osteoblasts of mandibular bone, again starting precisely with the onset of osteogenesis (day E13/14). No other cells were seen to transcribe the mutant gene. By these criteria, transcription of the Mov13 allele constitutes a true differentiation marker for odontoblasts and osteoblasts. Expression of the mutant allele in these two specialized cell types, in contrast to its transcriptional block in all other mesodermal cells ('fibroblasts'), suggests tissue-specific differences in the regulation of the alpha 1(I) collagen gene.

This article has been cited by other articles:

				S. G. Hormuzdi, R. Penttinen, R. Jaenisch, and P. Bornstein A Gene-Targeting Approach Identifies a Function for the First Intron in Expression of the alpha 1(I) Collagen Gene Mol. Cell. Biol., June 1, 1998; 18(6): 3368 - 3375. [Abstract] [Full Text]

				P.-L. Lukinmaa, G. Allemanni, J. Waltimo, and L. Zardi Immunoreactivity of Tenascin-C in Dentin Matrix in Dentinogenesis Imperfecta Associated with Osteogenesis Imperfecta Journal of Dental Research, January 1, 1996; 75(1): 581 - 587. [Abstract] [PDF]

				P.-L. Lukinmaa, A. Vaahtokari, S. Vainio, and I. Thesleff Expression of Type I Collagen Pro-{alpha}2 Chain mRNA in Adult Human Permanent Teeth as Revealed by in situ Hybridization Journal of Dental Research, January 1, 1992; 71(1): 36 - 42. [Abstract] [PDF]