RESEARCH ON THE FUNCTION OF BONE SIALOPROTEIN

骨唾液酸蛋白的功能研究

基本信息

批准号：
11671413
负责人：
MURAI Hajime
金额：
$ 1.98万
依托单位：
Akita University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

We obtained following three findings on the function of bone sialoprotein(BSP).1. We investigated molecular interaction between BSP and Type I collagen (COL1) molecules by observing the modification of the time course of the COL1 fibrillogenesis in vitro, BSP dramatically promoted the COL1 fibrillogensis at slightly acidic (pH6.55) condition, dose depehdently. However, in near neutral (pH7.25) or slightly alkaline (pH7.67) condition, BSP did not affect the kinetics. Decorin, plasma fibronectin, and chondroitin sulfate did not affect the kinetics, at any pH conditions. This findings suggested that BSP performed some functions in bone turnover at the initiation of bone formation in the resorption lacuna of acidic milieu just after osteoclasts dettached in vivo.2. The cell attachment assay by osteoblastic cell line (MC-3T3 E1 cell) was performed, on the plastic surface coated by only BSP, and on the surface coated by at first by BSP, thereafter, coated by plasma fibronectin(PFN) secondly. The surface coated by pFN after BSP collected significantly more cells than the surface coated only by BSP. This cell behavior suggested that pFN bound BSP that had already bound on the surface. This result suggested that in vivo BSP functions as an anchor for the other ECM (extracellular matrix) molecules, such as FN, etc. on hydroxyapatite crystal.3. The existence of BSP in blood mede us looked for the serum components which interacted with BSP. We found at least one molecule which bound to BSP fixed on agarose gel. This substance was determined to thrombospondin (TSP1) by Western blot. This results, TSP1 binds BSP in vitro, suggests that BSP is functioning as an anchor in bone ECM for TSP1 derived from blood circulation or secreted by osteoblasts. BSP may provides TSP1 with the milieu where TSP interacts with such bioactive ECM proteins.

我们在三个关于骨唾液蛋白（BSP）的功能的发现后获得了。1。我们通过观察体外Col1纤维生成的时间过程的修饰，在略微酸（pH6.55）的情况下，BSP急剧促进了Col1纤维生成的时间，研究了BSP和I型胶原蛋白（COL1）分子之间的分子相互作用。但是，在接近中性（PH7.25）或稍碱（pH7.67）的情况下，BSP不会影响动力学。在任何pH条件下，decorin，血浆纤连蛋白和硫酸软骨素都不会影响动力学。这一发现表明，BSP在酸性环境的吸收性间隙中的骨形成开始，在酸性环境中的吸收裂缝中，在体内dettach。在仅BSP覆盖的塑料表面上进行了成骨细胞系（MC-3T3 E1细胞）的细胞附着测定，然后在BSP上涂有bsp的表面上，然后由等离子纤维蛋白（PFN）涂覆。 BSP收集后，PFN覆盖的表面明显多于仅由BSP覆盖的表面。这种细胞行为表明，PFN结合了已经结合在表面上的BSP。该结果表明，体内BSP充当另一个ECM（细胞外基质）分子（例如FN等）的锚固剂。3。血液中BSP的存在寻找与BSP相互作用的血清成分。我们发现至少有一个与固定在琼脂糖凝胶上的BSP结合的分子。该物质通过蛋白质印迹确定为血小板传播（TSP1）。结果，TSP1在体外结合了BSP，这表明BSP在骨骼ECM中充当源自血液循环或由成骨细胞分泌的TSP1的锚固剂。 BSP可能会提供TSP1与TSP与这种生物活性ECM蛋白相互作用的环境。