Gene expression of BMP family and receptors during tooth development

骨形态发生蛋白是一种可扩散的信号分子，调节诱导性组织间的相互作用，在发育阶段器官结构的上皮-间质相互作用中起重要作用。采用原位杂交技术检测牙胚发育过程中骨形成蛋白基因的表达。所有标本均来源于C57 BL小鼠。将所有样本在4℃下浸入4%多聚甲醛磷酸盐缓冲液中16小时。所有固定标本均在梯度乙醇中脱水，氯仿处理，石蜡包埋。取4 mm厚的切片，转移到3-（三乙氧基硅）-丙胺包被的玻片上，37℃加热5 hr，用SP 6/T7转录试剂盒制备特异性地高辛标记的BMP-2.3.4.5.6.7单链RNA探针，观察出生后11 d的BMP-4和BMP-7基因表达。从出生后12天开始观察BMP-2基因的表达。免疫组化法观察这些蛋白的表达 关于我们 与基因表达一致。提示BMP-2、4、7在牙齿发育早期的上皮间质相互作用中与牙胚细胞的形态发生和分化有关。帽状期晚期釉上皮内有BMP-5基因表达。这些结果表明BMP-5在牙釉质和牙本质形成中起重要作用。基底膜（BM）是一种高度特化的细胞外基质的薄片状结构，它将上皮细胞和基质细胞分隔开。IV型胶原蛋白是哺乳动物BM的主要成分，是一个由六条不同多肽链组成的家族。这些被指定为α 1（IV）至α 6（IV）），它们由六个不同的基因COL 4A 1至COL 4A 6编码。牙发生是一个复杂的过程，涉及诱导和诱导的影响，牙源性上皮和外胚间充质，和BM之间插入这两个组织的功能作为一个调节器和调制器的这些相互作用。以前的研究已经检查了各种BM成分，包括IV型胶原和层粘连蛋白，以确定它们在牙齿形态发生和细胞分化过程中的作用。在小鼠磨牙胚发育的这项研究中，我们观察到，在牙齿器官发生的各个阶段，位于牙齿BM中的胶原IV亚型显示出阶段和位置特异性的分布模式。这些结果表明，阶段和位置特异性分布的IV型胶原异构体和骨形成蛋白与牙齿形态发生。少

Bone morphogenetic proteins are diffusible signaling molecules regulating inductive tissue interactions and play inportant roles in epithelialmesenchymal interaction of organ structure during developmental stage. We examined BMPs gene expression during developmental stage of tooth germ using in situ hybridization method. All specimens were derived from C57BL mouse. All specimens were immersed in 4 % paraformaldehyde solution in phosphate buffer for 16 hr at 4℃. All fixed specimens were dehydrated in graded ethanol, processed in chloroform, and embedded in paraffin. Sections of 4mm were cutt and transferred to 3-(Triethcxysilyl)-propylamin coated slides and heated at 37℃ for 5 hr. BMP-2.3.4.5.6.7 specific digoxgenin-labeled single stranded RNA probes were prepared using an SP6/T7 transcription kit.BMP-4 and 7 gene expressions were observed from prenatal 11 days. BMP-2 gene expression was observed from paranatal 12 days. These protein expressions using immunohistochemistry were observed … More coincidence with gene expression. These results suggested BMP-2,4,7 were related with morphogenesis and tooth germ cell differentiation in epithelial mesenchymal interacton from early stage of tooth development. BMP-5 gene expression was observed inner enamel epithelium in the late cap stage. These results suggested BMP-5 play important role of enamel and dentin formation.The basement membrane (BM) assembly is a thin sheet-like highly specialized structure of extracellular matrix that separates the epithelial cells from the stroma. Type IV collagen, the major component of mammalian BM, is a family of six distinct polypeptide chains. These are designated alpha1(IV) to alpha6(IV)) and they are encoded by six distinct genes, COL4A1 to COL4A6. Odontogenesis is a complex process involving inductive and reciprocally inductive influences of odontogenic epithelium and ectomesenchyme, and the BM interposed between these two tissues functions as a regulator and modulator of these interactions. Previous studies have examined various BM constituents including collagen IV and laminin to determine their roles during tooth morphogenesis and cytodifferentation. In this study on mouse molar germ development, we observed that collagen IV isoforms localized in the dental BM at various stages of tooth organogenesis showed a stage- and position-specific distribution pattern. These results suggest that stage- and position-specific distribution of collagen IV isoform and BMPs related with tooth morphogenesis. Less