Srayko Martin, Kaya Aynur, Stamford Joanne, Hyman Anthony A
Max-Planck-Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, D-01307 Dresden, Germany.
Dev Cell. 2005 Aug;9(2):223-36. doi: 10.1016/j.devcel.2005.07.003.
Microtubules (MTs) are dynamic polymers that undergo cell cycle and position-sensitive regulation of polymerization and depolymerization. Although many different factors that regulate MT dynamics have been described, to date there has been no systematic analysis of genes required for MT dynamics in a single system. Here, we use a transgenic EB1::GFP strain, which labels the growing plus ends of MTs, to analyze the growth rate, nucleation rate, and distribution of growing MTs in the Caenorhabditis elegans embryo. We also present the results from an RNAi screen of 40 genes previously implicated in MT-based processes. Our findings suggest that fast microtubule growth is dependent on the amount of free tubulin and the ZYG-9-TAC-1 complex. Robust MT nucleation by centrosomes requires AIR-1, SPD-2, SPD-5, and gamma-tubulin. However, we found that centrosomes do not nucleate MTs to saturation; rather, the depolymerizing kinesin-13 subfamily member KLP-7 is required to limit microtubule outgrowth from centrosomes.
微管（MTs）是动态聚合物，其聚合和解聚受到细胞周期和位置敏感的调控。尽管已经描述了许多调节微管动态的不同因素，但迄今为止，尚未在单一系统中对微管动态所需基因进行系统分析。在这里，我们使用转基因EB1::GFP菌株，该菌株标记微管生长的正端，以分析秀丽隐杆线虫胚胎中微管的生长速率、成核速率和生长微管的分布。我们还展示了对先前涉及基于微管过程的40个基因进行RNA干扰筛选的结果。我们的研究结果表明，快速的微管生长取决于游离微管蛋白的量和ZYG-9-TAC-1复合体。中心体强大的微管成核需要AIR-1、SPD-2、SPD-5和γ-微管蛋白。然而，我们发现中心体不会将微管成核至饱和；相反，解聚的驱动蛋白-13亚家族成员KLP-7是限制微管从中心体向外生长所必需的。
