Rothwell S W, Grasser W A, Murphy D B
J Cell Biol. 1986 Feb;102(2):619-27. doi: 10.1083/jcb.102.2.619.
Mixtures of pre-formed microtubules, polymerized from chicken erythrocyte and brain tubulin, rapidly anneal end-to-end in vitro in standard microtubule assembly buffer. The erythrocyte tubulin segments in annealed heteropolymers can be distinguished by an immunoelectron microscopic assay that uses an antibody specific for chicken erythrocyte beta-tubulin. An annealing process is consistent with the following observations: (a) Microtubule number decreases while the polymer mass remains constant. (b) As the total number of microtubules declines, the number of heteropolymers, and the number of segments contained in each heteropolymer, increases. (c) The size of the segments determined after annealing and antibody labeling is the same as the original microtubule polymers. (d) Points of discontinuity in the annealing heteropolymers can be observed directly by electron microscopy, and correspond to type-specific polymer domains. The junctions probably represent initial contact points during the annealing process. Microtubule annealing occurs rapidly in vitro and may be significant for determining properties of microtubule dynamics in vivo.
由鸡红细胞微管蛋白和脑微管蛋白聚合而成的预制微管混合物，在标准微管组装缓冲液中能在体外迅速进行端端退火。通过使用对鸡红细胞β微管蛋白特异的抗体的免疫电子显微镜检测法，可区分退火异源聚合物中的红细胞微管蛋白片段。退火过程与以下观察结果一致：(a)微管数量减少，而聚合物质量保持恒定。(b)随着微管总数下降，异源聚合物数量以及每个异源聚合物中所含片段数量增加。(c)退火和抗体标记后确定的片段大小与原始微管聚合物相同。(d)通过电子显微镜可直接观察到退火异源聚合物中的不连续点，且这些点对应于类型特异性聚合物结构域。这些连接点可能代表退火过程中的初始接触点。微管退火在体外迅速发生，可能对确定体内微管动力学特性具有重要意义。
