Podosome structures as a focal adhesion appeared in osteoclasts in culture

培养的破骨细胞中出现作为粘着斑的足小体结构

基本信息

批准号：
16591848
负责人：
AKISAKA Toshitaka
金额：
$ 1.92万
依托单位：
Asahi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2005
项目状态：
已结题

项目摘要

Osteoclasts are large, multinucleated cells specialized for the degradation of mineralized matrix. In the harmony with osteoblastic bone formation, osteoclastic bone resorption is essential for the dynamic equilibrium of bone homeostasis. The aim of our present research was to visualize how the plasma membrane is modified and how the cytoskeleton interacts with the attachment, and ruffled border regions of resorbing osteoclasts. In order to view the surface modification of membranes and associated cytoskeleton, we employed the method of cell shearing combined with quick freezing and rotary replication to expose and replicate an extensive area of the cytoplasmic face of the surface membrane of osteoclasts in contact with synthetic apatite as a substratum. The membrane apposed to the apatite was composed of 3 different domains : the attachment zone, ruffled border, and the remainder. In the attachment zone, a highly organized actin filament network formed dot-shaped, F-actin rich adhesion sites, so-called podosomes, and the actin ring. The cytoskeletal filament of podosomes and actin ring appeared to be in direct contact with the cytoplasmic surface of the underlying membrane. Within the actin ring, individually recognizable podosomes were well preserved, which indicates that the actin ring was probably derived from the fusion of podosomes.Cell shearing combined with quick-freezing microscopy was used as we considered that this method would give more detailed information on the cytoplasmic surface of membrane in the attachment zone and ruffled border region.

破骨细胞是大型多核细胞，专门用于矿化基质降解。在与成骨细胞骨形成的和谐中，整骨骨吸收对于骨稳态的动态平衡至关重要。我们目前的研究的目的是可视化质膜如何修饰以及细胞骨架如何与附着相互作用，以及吸收破骨细胞的褶皱边界区域。为了查看膜和相关的细胞骨架的表面修饰，我们采用了细胞剪切方法与快速冷冻和旋转复制结合，以暴露并复制与骨质质体的表面膜的广泛区域，并与合成的apatite suspatite接触。磷灰石上的膜由3个不同的域组成：附着区，褶皱边框和其余部分。在附件区域，一个高度有组织的肌动蛋白丝网络形成了点形，富含F-肌动蛋白的粘附位点，所谓的足体和肌动蛋白环。足体和肌动蛋白环的细胞骨骼丝似乎与下面膜的细胞质表面直接接触。在肌动蛋白环内，可以很好地保存了可识别的足体，这表明肌动蛋白环可能源自足体的融合。细胞剪切与快速冻结显微镜相结合，因为我们认为这种方法将提供有关附着区域和层层边界和层层边界质质表面的更详细信息。