Insights into centriole geometry revealed by cryotomography of doublet and triplet centrioles.
Insights into centriole geometry revealed by cryotomography of doublet and triplet centrioles.
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DOI：
10.7554/elife.36851
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发表时间：
2018-08-06
期刊：
影响因子：
7.7
通讯作者：
Agard DA
中科院分区：
文献类型：
--
作者：
Greenan GA;Keszthelyi B;Vale RD;Agard DA
中心粒是由9根单线、双线或三线微管组成的圆柱形集合体，对运动纤毛和感觉纤毛的形成至关重要。虽然纤毛的结构正在以越来越高的分辨率被定义，但中心粒结构仍然知之甚少。在这里，我们使用电子冷冻断层扫描来确定哺乳动物(三胞胎)和果蝇(双胞胎)中心粒的结构。哺乳动物的中心粒有两个不同的结构域：由A-C连接子连接的200 nm近端核心区和远端结构域，其中C-小管不完整，一对新的连接稳定了组装，产生了更接近纤毛轴丝的几何形状。果蝇的中心粒类似于哺乳动物的核心，但它们的双微管通过A管连接。核心区域长度的共性，以及哺乳动物中心粒的突变，表明了一种保守的长度设定机制。意想不到的连接物多样性表明独特的中心粒结构是如何在不同的组织和生物体中出现的。
Centrioles are cylindrical assemblies comprised of 9 singlet, doublet, or triplet microtubules, essential for the formation of motile and sensory cilia. While the structure of the cilium is being defined at increasing resolution, centriolar structure remains poorly understood. Here, we used electron cryo-tomography to determine the structure of mammalian (triplet) and Drosophila (doublet) centrioles. Mammalian centrioles have two distinct domains: a 200 nm proximal core region connected by A-C linkers, and a distal domain where the C-tubule is incomplete and a pair of novel linkages stabilize the assembly producing a geometry more closely resembling the ciliary axoneme. Drosophila centrioles resemble the mammalian core, but with their doublet microtubules linked through the A tubules. The commonality of core-region length, and the abrupt transition in mammalian centrioles, suggests a conserved length-setting mechanism. The unexpected linker diversity suggests how unique centriolar architectures arise in different tissues and organisms.