Differential expression of type I and type III collagen genes during tooth development.
Collagen gene expression during mouse molar tooth development was studied by quantitative in situ hybridization techniques. Different expression patterns of type I and type III collagen mRNAs were observed in the various mesenchymal tissues that constitute the tooth germ. High concentration for pro-alpha 1(I) and pro-alpha 2(I) collagen mRNAs were found within the osteoblasts. We found that the cellular content of type I collagen mRNAs in the odontoblasts varies throughout the tooth formation: whereas mRNA concentration for pro-alpha 1(I) collagen decreases and that of pro-alpha 2(I) increases, during postnatal development. Moreover, different amounts of pro-alpha 1(I) and pro-alpha 2(I) collagen mRNAs were observed in crown and root odontoblasts, respectively. Type III collagen mRNAs were detected in most of the mesenchymal cells, codistributed with type I collagen mRNAs, except in odontoblasts and osteoblasts. Finally, this study reports differential accumulation of collagen mRNAs during mouse tooth development and points out that type I collagen gene expression is regulated by distinct mechanisms during odontoblast differentiation process. These results support the independent expression of the collagen genes under developmental tissue-specific control.
Andujar
M B
MB
Laboratoire d'Histophysiologie et de Pathologie, Faculté d'Odontologie, UCBL, Lyon, France.
Couble
P
P
Couble
M L
ML
Magloire
H
H
D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D003094:Collagen / Q000235:genetics*; D015342:DNA Probes; D015870:Gene Expression / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D008963:Molar; D015336:Molecular Probe Techniques; D009804:Odontoblasts / Q000502:physiology / Q000648:ultrastructure; D009805:Odontogenesis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D014083:Tooth Germ / Q000648:ultrastructure
D015342:DNA Probes; D012333:RNA, Messenger; D003094:Collagen