Department of Biochemistry and Biophysics and the Howard Hughes Medical Institute, University of California San Francisco, San Francisco, California 94158, USA.
Nat Cell Biol. 2012 Nov;14(11):1159-68. doi: 10.1038/ncb2597. Epub 2012 Oct 21.
As the main microtubule-organizing centre in animal cells, the centrosome has a fundamental role in cell function. Surrounding the centrioles, the pericentriolar material (PCM) provides a dynamic platform for nucleating microtubules. Although the importance of the PCM is established, its amorphous electron-dense nature has made it refractory to structural investigation. By using SIM and STORM subdiffraction-resolution microscopies to visualize proteins critical for centrosome maturation, we demonstrate that the PCM is organized into two main structural domains: a layer juxtaposed to the centriole wall, and proteins extending farther away from the centriole organized in a matrix. Analysis of Pericentrin-like protein (PLP) reveals that its carboxy terminus is positioned at the centriole wall, it radiates outwards into the matrix and is organized in clusters having quasi-nine-fold symmetry. By RNA-mediated interference (RNAi), we show that PLP fibrils are required for interphase recruitment and proper mitotic assembly of the PCM matrix.
作为动物细胞中的主要微管组织中心，中心体在细胞功能中起着基础性的作用。围绕着中心粒，中心粒周围物质（PCM）为微管的成核提供了一个动态平台。尽管 PCM 的重要性已经确立，但由于其无定形的电子致密性质，使得它难以进行结构研究。通过使用 SIM 和 STORM 亚衍射分辨率显微镜来可视化对中心体成熟至关重要的蛋白质，我们证明 PCM 组织成两个主要的结构域：一个与中心粒壁相邻的层，以及远离中心粒更远的蛋白组织成一个基质。对 Pericentrin-like protein (PLP) 的分析表明，其羧基末端位于中心粒壁上，向外辐射到基质中，并组织成具有准九倍对称性的簇。通过 RNA 介导的干扰（RNAi），我们表明 PLP 纤维对于间期招募和 PCM 基质的适当有丝分裂组装是必需的。
