Darko Kero, Katarina Vukojevic, Petra Stazic, Danijela Sundov, Snjezana Mardesic Brakus, Mirna Saraga-Babic
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引用次数: 14
Abstract
Before the secretion of hard dental tissues, tooth germs undergo several distinctive stages of development (dental lamina, bud, cap and bell). Every stage is characterized by specific proliferation patterns, which is regulated by various morphogens, growth factors and homeodomain proteins. The role of MSX homeodomain proteins in odontogenesis is rather complex. Expression domains of genes encoding for murine Msx1/2 during development are observed in tissues containing highly proliferative progenitor cells. Arrest of tooth development in Msx knockout mice can be attributed to impaired proliferation of progenitor cells. In Msx1 knockout mice, these progenitor cells start to differentiate prematurely as they strongly express cyclin-dependent kinase inhibitor p19INK4d. p19INK4d induces terminal differentiation of cells by blocking the cell cycle in mitogen-responsive G1 phase. Direct suppression of p19INK4d by Msx1 protein is, therefore, important for maintaining proliferation of progenitor cells at levels required for the normal progression of tooth development. In this study, we examined the expression patterns of MSX1, MSX2 and p19INK4d in human incisor tooth germs during the bud, cap and early bell stages of development. The distribution of expression domains of p19INK4d throughout the investigated period indicates that p19INK4d plays active role during human tooth development. Furthermore, comparison of expression domains of p19INK4d with those of MSX1, MSX2 and proliferation markers Ki67, Cyclin A2 and pRb, indicates that MSX-mediated regulation of proliferation in human tooth germs might not be executed by the mechanism similar to one described in developing tooth germs of wild-type mouse.
期刊介绍:
Organogenesis is a peer-reviewed journal, available in print and online, that publishes significant advances on all aspects of organ development. The journal covers organogenesis in all multi-cellular organisms and also includes research into tissue engineering, artificial organs and organ substitutes.
The overriding criteria for publication in Organogenesis are originality, scientific merit and general interest. The audience of the journal consists primarily of researchers and advanced students of anatomy, developmental biology and tissue engineering.
The emphasis of the journal is on experimental papers (full-length and brief communications), but it will also publish reviews, hypotheses and commentaries. The Editors encourage the submission of addenda, which are essentially auto-commentaries on significant research recently published elsewhere with additional insights, new interpretations or speculations on a relevant topic. If you have interesting data or an original hypothesis about organ development or artificial organs, please send a pre-submission inquiry to the Editor-in-Chief. You will normally receive a reply within days. All manuscripts will be subjected to peer review, and accepted manuscripts will be posted to the electronic site of the journal immediately and will appear in print at the earliest opportunity thereafter.