Department of General Dentistry, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China.
Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA.
Arch Oral Biol. 2017 Oct;82:33-37. doi: 10.1016/j.archoralbio.2017.04.031. Epub 2017 May 31.
To compare the expression patterns of two multiple transcripts derived from DSP-PP gene during tooth development. One is DSP-only transcript (i.e. does not encode PP) and the other is DSP-PP transcript, a main DSP-PP transcript.
Unique antisense and sense riboprobes were generated from DSP-only and DSPPP cDNAs for in situ studies to examine DSP-only and DSP-PP transcript expression in developing molars. Paraffin-embedded sections (5-7μ m) from embryonic 20day, postnatal 2, 3 and 6days were deparaffined and hydrated. Tissues were prehybridized, then hybridized with DSP-only and DSP-PP anti-sense (AS) or sense (S) Digoxigenin labeled-riboprobes overnight, and washed. Anti-Digoxigenin antibodies conjugated to alkaline phosphatase were used to detect the presence of bound riboprobes by color reaction with NBT/BCIP. Stro-1 antibody was used for immunohistochemical analysis of Stro-1 protein expression in rat molars.
We found that unlike the DSP-PP transcript, the DSP-only transcript does not express in the entire polarized mature odontoblasts but is expressed in the areas subjacent to the mature odontoblast layer. In addition, DSP-only transcript is expressed in the dental pulp. Interestingly, Stro-1 protein, a stem cell marker, was also identified in the areas subjacentto odontoblasts and in dental pulp.
Differential expression of DSP-only and DSP-PP transcripts suggest that these two kinds of transcripts may play different roles during dentinogenesis. DSP-PP transcript is expressed in mature odontoblasts, which actively participates in dentin formation. DSP-only transcript might have a different function.
比较牙发育过程中两个来源于 DSP-PP 基因的多转录本的表达模式。一个是仅 DSP 转录本（即不编码 PP），另一个是 DSP-PP 转录本，这是主要的 DSP-PP 转录本。
从 DSP-only 和 DSPPP cDNA 生成独特的反义和正义核糖探针，用于原位研究以检查发育中磨牙中仅 DSP 和 DSP-PP 转录本的表达。从胚胎 20 天、出生后 2、3 和 6 天的石蜡包埋切片（5-7μm）中脱蜡和水化。组织进行预杂交，然后用 DSP-only 和 DSP-PP 反义（AS）或正义（S）Digoxigenin 标记的核糖探针杂交过夜，并进行洗涤。用抗 Digoxigenin 抗体与碱性磷酸酶缀合，通过与 NBT/BCIP 的颜色反应检测结合的核糖探针的存在。Stro-1 抗体用于免疫组织化学分析大鼠磨牙中 Stro-1 蛋白的表达。
我们发现，与 DSP-PP 转录本不同，仅 DSP 转录本不在整个极化成熟成牙本质细胞中表达，而是在成熟成牙本质细胞层下方的区域表达。此外，仅 DSP 转录本在牙髓中表达。有趣的是，干细胞标志物 Stro-1 蛋白也在成牙本质细胞下方区域和牙髓中被鉴定出来。
DSP-only 和 DSP-PP 转录本的差异表达表明这两种转录本在牙本质生成过程中可能发挥不同的作用。DSP-PP 转录本在成熟的成牙本质细胞中表达，这些细胞积极参与牙本质形成。仅 DSP 转录本可能具有不同的功能。
