Howard Joe, Hyman Anthony A
Max Plank Institute of Molecular Cell Biology and Genetics (MPI-CBG), Pfotenhauerstrasse 108, 01307 Dresden, Germany.
Nature. 2003 Apr 17;422(6933):753-8. doi: 10.1038/nature01600.
An important function of microtubules is to move cellular structures such as chromosomes, mitotic spindles and other organelles around inside cells. This is achieved by attaching the ends of microtubules to cellular structures; as the microtubules grow and shrink, the structures are pushed or pulled around the cell. How do the ends of microtubules couple to cellular structures, and how does this coupling regulate the stability and distribution of the microtubules? It is now clear that there are at least three properties of a microtubule end: it has alternate structures; it has a biochemical transition defined by GTP hydrolysis; and it forms a distinct target for the binding of specific proteins. These different properties can be unified by thinking of the microtubule as a molecular machine, which switches between growing and shrinking modes. Each mode is associated with a specific end structure on which end-binding proteins can assemble to modulate dynamics and couple the dynamic properties of microtubules to the movement of cellular structures.
微管的一个重要功能是在细胞内移动诸如染色体、有丝分裂纺锤体和其他细胞器等细胞结构。这是通过将微管的末端附着到细胞结构上来实现的；随着微管的生长和收缩，这些结构在细胞内被推动或拉动。微管的末端是如何与细胞结构耦合的，以及这种耦合如何调节微管的稳定性和分布？现在很清楚，微管末端至少有三个特性：它具有交替结构；它具有由GTP水解定义的生化转变；并且它形成了特定蛋白质结合的独特靶点。通过将微管视为一种分子机器，这些不同的特性可以统一起来，该分子机器在生长和收缩模式之间切换。每种模式都与特定的末端结构相关联，末端结合蛋白可以在该结构上组装，以调节动力学并将微管的动态特性与细胞结构的运动耦合起来。
