Matsuura T, Duarte W R, Cheng H, Uzawa K, Yamauchi M
CB#7455, Dental Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7455, USA.
Matrix Biol. 2001 Sep;20(5-6):367-73. doi: 10.1016/s0945-053x(01)00142-1.
Small leucine-rich proteoglycans (SLRPs) have a number of biological functions and some of them are thought to regulate collagen mineralizaton in bone and tooth. We have previously identified and immunolocalized two members of the SLRPs family, decorin and biglycan, in bovine tooth/periodontium. To investigate their potential roles in tooth development, we examined the mRNA expression patterns of decorin, biglycan and type I collagen in newborn (day 19) mice tooth germs by in situ hybridization. At this developmental stage, the first maxillary and mandibular molars include stages before and after secretion of the predentin matrix, respectively. The expression of decorin mRNA coincided with that of type I collagen mRNA and was mostly observed in secretory odontoblasts, while the biglycan mRNA was expressed throughout the tooth germ, including pre-secretory odontoblasts/ameloblasts, dental papilla and stellate reticulum. However, its signal in secretory odontoblasts was not as evident as that of decorin. In mandibular incisors, where a significant amount of predentin matrix and a small amount of enamel matrix were already secreted, a similar differential expression pattern was observed. In secretory ameloblasts the biglycan mRNA expression was apparent, while that of decorin was not. These differential expression patterns suggest the distinct roles of biglycan and decorin in the process of tooth development.
富含亮氨酸小分子蛋白聚糖（SLRPs）具有多种生物学功能，其中一些被认为可调节骨骼和牙齿中的胶原蛋白矿化。我们之前已在牛牙/牙周组织中鉴定并免疫定位了SLRPs家族的两个成员，即核心蛋白聚糖和双糖链蛋白聚糖。为了研究它们在牙齿发育中的潜在作用，我们通过原位杂交检测了新生（第19天）小鼠牙胚中核心蛋白聚糖、双糖链蛋白聚糖和I型胶原蛋白的mRNA表达模式。在这个发育阶段，第一上颌磨牙和下颌磨牙分别处于前期牙本质基质分泌前后的阶段。核心蛋白聚糖mRNA的表达与I型胶原蛋白mRNA的表达一致，主要在分泌性成牙本质细胞中观察到，而双糖链蛋白聚糖mRNA在整个牙胚中表达，包括分泌前的成牙本质细胞/成釉细胞、牙乳头和星网状层。然而，其在分泌性成牙本质细胞中的信号不如核心蛋白聚糖明显。在下颌切牙中，已经分泌了大量的前期牙本质基质和少量的釉质基质，观察到了类似的差异表达模式。在分泌性成釉细胞中，双糖链蛋白聚糖mRNA表达明显，而核心蛋白聚糖的表达则不明显。这些差异表达模式表明双糖链蛋白聚糖和核心蛋白聚糖在牙齿发育过程中具有不同的作用。
