Procentriole assembly revealed by cryo-electron tomography
Procentriole assembly revealed by cryo-electron tomography
复制标题
DOI：
10.1038/emboj.2010.45
复制
发表时间：
2010-05-05
期刊：
影响因子：
11.4
通讯作者：
Tassin, Anne-Marie
中科院分区：
文献类型：
--
作者：
Guichard, Paul;Chretien, Denis;Tassin, Anne-Marie
中心体是细胞器，在微管网络的空间组织中起着重要作用。中心体由两个中心粒组成，它们在细胞周期中只复制一次，从每个成熟的中心粒产生一个前中心粒。尽管中心体起着重要的作用，但中心粒复制的详细结构机制在很大程度上仍然未知。在这里，我们用低温电子断层扫描描述了人类前心房的组装。在从人淋巴母细胞分离的中心体中，我们观察到九个微管三胞胎中的每一个都围绕一个周期性的中心结构独立生长。a微管的近端被一个锥形结构所覆盖，B微管和c微管从其壁上双向拉长。这些观察结果表明，γ微管环复合物（c-TuRC）通过使a微管成核，从而在原戊三醇的形成中起基本作用，而a微管作为b微管延伸的模板，反过来又支持c微管的生长。该研究为研究中心粒组装过程中涉及的初始结构事件提供了新的见解，并为确定纳米尺度上中心粒复制的分子机制奠定了基础。EMBO杂志（2010）29,1565-1572。doi: 10.1038 / emboj.2010.45;2010年3月25日在线发布
Centrosomes are cellular organelles that have a major role in the spatial organisation of the microtubule network. The centrosome is comprised of two centrioles that duplicate only once during the cell cycle, generating a procentriole from each mature centriole. Despite the essential roles of centrosomes, the detailed structural mechanisms involved in centriole duplication remain largely unknown. Here, we describe human procentriole assembly using cryo-electron tomography. In centrosomes, isolated from human lymphoblasts, we observed that each one of the nine microtubule triplets grows independently around a periodic central structure. The proximal end of the A-microtubule is capped by a conical structure and the B- and C-microtubules elongate bidirectionally from its wall. These observations suggest that the gamma tubulin ring complex (c-TuRC) has a fundamental role in procentriole formation by nucleating the A-microtubule that acts as a template for B-microtubule elongation that, in turn, supports C-microtubule growth. This study provides new insights into the initial structural events involved in procentriole assembly and establishes the basis for determining the molecular mechanisms of centriole duplication on the nanometric scale. The EMBO Journal (2010) 29, 1565-1572. doi:10.1038/emboj.2010.45; Published online 25 March 2010