摘要
目的观察转录调节因子LMO4在鼠磨牙牙胚形态发生中的基因表达,并与Shh信号分子的基因表达进行比较.方法制备昆明小鼠磨牙形态发育各期标本(E11.5~P1.5), whole-mount 原位杂交分析 LMO4 mRNA 在鼠胚中的表达与分布.切片原位杂交分析LMO4 及 Shh mRNA 在牙胚中的表达与分布.用免疫组化SP法对增殖细胞核抗原(PCNA)进行定位研究.结果 whole-mount 原位杂交发现,在E11.5, LMO4 mRNA在上下颌突、肢芽、脑、表皮和体节中呈阳性表达.切片原位杂交发现, E13.5~E16.5, LMO4 mRNA 分别在牙蕾上皮、成釉器两侧尖部和颈环处呈阳性表达,Shh mRNA表达于釉结; E18.5~P1.5, LMO4 mRNA 在成釉细胞层和中间层呈阳性表达.免疫组化染色发现,E13.5~E16.5,部分牙蕾上皮及颈环处细胞PCNA阳性,恰与LMO4基因表达部位重合.结论 LMO4在牙胚形态发生中呈时空特异性表达并且局限表达于上皮来源的组织.LMO4与Shh信号分子表达范围邻近,在牙胚发育早期可能调控细胞增殖,晚期可能参与成釉细胞的分化.
Objective To investigate the expression of transcription regulator LMO4 mRNA in the developing mouse molar and compare the expression pattern of LMO4 with that of Shh signaling molecule. Methods Wild-type embryos used in this study ( E11.5 - P1.5 ) were generated by mating Kun-Ming mice. The expression pattern of LMO4 during organ development was carried on by whole-mount in situ hybridization. The expression patterns of LMO4 and Shh mRNA during molar development were analysed by section in situ hybridization. Immunohistochemical staining of PCNA was carried on by SP method. Results LMO4 mRNA was widespread at early embryonic stages ( E11.5 ) with positive hybridization signal in the mandibular reagon, limb bud, brain, epidermis and somites revealed by whole-mount in situ hybridization. Section in situ hybridization showed that LMO4 was expressed in the tooth bud, the two tips of the enamel organ and the cervical loop from E13.5 to E16. 5. While Shh was localized in the enamel knot on El4. 5. On E18. 5- P1.5, LMO4 transcripts were distributed in the ameloblast and the stratum intermedium. On E13.5 - E16. 5, the tooth bud cells and the cervical loop cells were PCNA positive. These were the same regions that showed LMO4 mRNA expression. Conclusions LMO4 was confined to the dental epithelium and had spatialtemporal expression patterns during tooth morphogenesis. The expression patterns of LMO4 and Shh were similar. In early tooth development, LMO4 might regulate cell proliferation. In late tooth development,it might participate in the ameloblast differentiation.
出处
《中华口腔医学杂志》
CAS
CSCD
北大核心
2005年第5期398-401,共4页
Chinese Journal of Stomatology
基金
国家自然科学基金资助项目(30171011)