Division of Histology, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido, Kanazawa 1757 Tobetsu-cho, Ishikari-gun, Hokkaido 061-0293, Japan.
Arch Oral Biol. 2010 Dec;55(12):995-1006. doi: 10.1016/j.archoralbio.2010.07.021. Epub 2010 Sep 1.
Versican is a large, aggregating chondroitin sulphate proteoglycan. In dental tissue, versican expression occurs primarily in mesenchymal tissue but rarely in epithelial tissue. We investigated the expression, localisation and synthesis of versican in the enamel organ of the developing tooth germ.
To elucidate versican localisation in vivo, in situ hybridisation and immunohistochemistry were conducted in foetal ICR mice at E11.5-E18.5. Epithelium and mesenchyme from the lower first molars at E16.0 were enzymatically separated and versican mRNA expression was investigated by semi-quantitative RT-PCR. Organ culture of the separated samples combined with metabolic labelling with [(35)S], followed by gel filtration, was performed to analyse secreted proteoglycans.
Versican mRNA was first expressed in the thickened dental epithelium at E12.0 and continued to be expressed in the enamel organ until the bell stage. Versican immunostaining was detected in the stellate reticulum areas from the bud stage to the apposition stage. The enamel organ at E16.0 expressed versican mRNA at a level comparable to that in dental mesenchyme. Furthermore, when compared to dental mesenchyme, about 1/2-3/4 of the [(35)S]-labelled versican-like large proteoglycan was synthesised and released into tissue explants by the enamel organ.
The dental epithelium of developing tooth germ is able to synthesise significant amounts of versican.
Versican 是一种大型聚集性软骨素硫酸蛋白聚糖。在牙齿组织中，Versican 的表达主要发生在间充质组织中，但很少发生在上皮组织中。我们研究了牙胚发育过程中釉器中 Versican 的表达、定位和合成。
为了阐明体内 Versican 的定位，我们在 E11.5-E18.5 的 ICR 胎鼠中进行了原位杂交和免疫组织化学研究。从 E16.0 的下颌第一磨牙中分离出上皮和间充质，并通过半定量 RT-PCR 研究 Versican mRNA 的表达。对分离的样本进行器官培养，结合 [(35)S]代谢标记，然后进行凝胶过滤，以分析分泌的蛋白聚糖。
Versican mRNA 于 E12.0 时在增厚的牙上皮中首次表达，并在钟状期前持续在釉器中表达。从芽状期到附著期，在星状网状区检测到 Versican 免疫染色。E16.0 的釉器表达的 Versican mRNA 水平与牙间充质相当。此外，与牙间充质相比，约 1/2-3/4的[(35)S]-标记的 Versican 样大蛋白聚糖由釉器合成并释放到组织外植体中。
发育中牙胚的牙上皮能够合成大量的 Versican。
