GENE REGULATION OF RAT DENTIN SIALOPROTEIN

尽管牙本质发生的机制尚不清楚，但 明确一组独特的细胞外基质 (ECM) 蛋白 参与前牙本质及其后续的形成 矿化形成牙本质。成熟的成牙本质细胞分泌胶原蛋白 矿化处的细胞边界和非胶原蛋白 (NCP) 前面（可能通过成牙本质细胞过程）。这里 NCP 形成 与胶原蛋白的复合物。形成碳酸盐磷灰石晶体，这 晶体引发和生长的特定位点过程被认为是 由胶原蛋白-NCP 复合物控制。 为了阐明细节 牙本质发生、与 NCP 相关的附加信息、它们的 需要新陈代谢和基因调控。特别感兴趣的是 牙本质 ECM 中独特发现的蛋白质。一种牙本质特异性蛋白质， 牙本质唾液酸蛋白 (DSP) 是一种 53 kDa 的蛋白质，是一种富含唾液酸的蛋白质 总体特性与细胞附着蛋白骨相似的蛋白质 唾液酸蛋白（BSP）和骨桥蛋白（OPN）。 然而，DSP是综合的 仅由成牙本质细胞和牙髓作用，而不由成骨细胞或其他细胞作用 类型。从 DSP 的 cDNA 推导的序列与那些不同 BSP、OPN 和其他蛋白质。 DSP 包含 N-的共有序列 和 O-糖基化位点，以及酪蛋白激酶和 11 磷酸化位点。 Northern 印迹检测到多个转录本 大约 4.6 kb 和 1.5 kb。最近的基因组Southern印迹分析 克隆强烈表明存在两个相关的 DSP 基因。 我们假设DSP的合成和分泌对于 形成健康的牙本质。为了检验这个假设，我们将 利用分子生物学技术来阐明基因结构和 他们的监管。我们提出以下具体目标：确定 DSP 基因的基因组组织。 2. 表征多个 DSP 转录本并检查空间和时间表达 这些成绩单。 3. 表征DSP基因的启动子 包括DNA序列、最小调控序列和核序列 转录因子和4.研究DSP的潜在调控 基因通过信号转导分子。本文概述的研究 该提案将为理解重要的内容提供坚实的分子基础 控制牙本质发生的调控事件。

Although the mechanisms involved in dentinogenesis are unknown, it is clear that a unique set of extracellular matrix (ECM) proteins participates in the formation of predentin and its subsequent mineralization to form dentin. Mature odontoblasts secrete collagen at the cell border and non-collagenous proteins (NCPs) at the mineralization front (possibly through odontoblastic processes). Here NCPs form complexes with collagen. Carbonate apatite crystals are formed and this site-specific process of crystal initiation and growth is believed to be controlled by the collagen-NCP complex. In order to elucidate details of dentinogenesis, additional information relative to the NCPs, their metabolism and gene regulation is needed. Of particular interest are proteins found uniquely in dentin ECM. One dentin specific protein, dentin sialoprotein (DSP), a 53 kDa protein, is a sialic acid-rich protein similar in overall properties to cell attachment proteins bone sialoprotein (BSP) and osteopontin (OPN). However, DSP is synthesized only by odontoblasts and dental pulp and not by osteoblasts or other cell types. The sequence of DSP deduced from its cDNA is dissimilar to those of BSP, OPN and other proteins. DSP contains consensus sequences for N- and O-glycosylation sites, as well as casein kinase and 11 phosphorylation sites. Northern blots detected multiple transcripts of approximately 4.6 kb and 1.5 kb. Recent Southern blot analysis of genomic clones strongly suggests the presence of two related DSP genes. We hypothesize that the synthesis and secretion of DSP is crucial to the formation of healthy dentin. In order to test this hypothesis, we will employ molecular biological techniques to elucidate gene structures and their regulation. We propose the following Specific Aims: i. To determine the genomic organization of DSP gene(s). 2. To characterize multiple DSP transcripts and to examine the spatial and temporal expression of these transcripts. 3. To characterize the promoter(s) of DSP gene(s) including DNA sequence, minimal regulatory sequences and nuclear transcription factors and 4. To study the potential regulation of the DSP gene(s) by signal transducing molecules. The studies outlined in this proposal will provide a solid molecular basis for understanding important regulatory events controlling dentinogenesis.