Wang Y H, Kollar E J, Upholt W B, Mina M
Department of BioStructure and Function, School of Dental Medicine, University of Connecticut Health Center, Farmington 06030, USA.
Eur J Oral Sci. 1998 Jan;106 Suppl 1:100-3. doi: 10.1111/j.1600-0722.1998.tb02159.x.
Previous heterospecific tissue recombinations indicate that mandibular epithelium exerts the first known inductive signal for odontogenesis in mouse embryos. BMP-4 and EGF are two growth factors implicated as signaling molecules mediating the initial inductive epithelial-mesenchymal interactions during odontogenesis. The purpose of the present study was to examine and compare the effects of these growth factors and mouse mandibular epithelium on expression of Msx-1 and Msx-2 genes in molar-forming mesenchyme. Agarose beads soaked in growth factors or pieces of mouse mandibular epithelium (E11) were placed in contact with E11 molar-forming mesenchyme and cultured for 24 h. Whole-mount in situ hybridization analysis revealed that, in contrast to mouse mandibular epithelium and BMP-4-releasing beads, EGF-releasing beads did not induce the expression of Msx-1 and Msx-2 in E11 molar-forming mesenchyme. These observations suggest that whereas BMP-4 may be involved in activation of Msx-1 and Msx-2 in the underlying mesenchyme, EGF may regulate events involved in the formation of dental lamina.
先前的异种组织重组表明，下颌上皮对小鼠胚胎牙齿发生施加了首个已知的诱导信号。骨形态发生蛋白-4（BMP-4）和表皮生长因子（EGF）是两种生长因子，被认为是在牙齿发生过程中介导初始诱导性上皮-间充质相互作用的信号分子。本研究的目的是检测和比较这些生长因子以及小鼠下颌上皮对磨牙形成间充质中Msx-1和Msx-2基因表达的影响。将浸泡在生长因子中的琼脂糖珠或小鼠下颌上皮（E11）片与E11磨牙形成间充质接触并培养24小时。整体原位杂交分析显示，与小鼠下颌上皮和释放BMP-4的珠子不同，释放EGF的珠子未诱导E11磨牙形成间充质中Msx-1和Msx-2的表达。这些观察结果表明，虽然BMP-4可能参与激活其下方间充质中的Msx-1和Msx-2，但EGF可能调节牙板形成过程中涉及的事件。
