McNally F J, Vale R D
Department of Pharmacology, University of California, San Francisco 94143.
Cell. 1993 Nov 5;75(3):419-29. doi: 10.1016/0092-8674(93)90377-3.
Eukaryotic cells rapidly reorganize their microtubule cytoskeleton during the cell cycle, differentiation, and cell migration. In this study, we have purified a heterodimeric protein, katanin, that severs and disassembles microtubules to tubulin dimers. The disassembled tubulin can repolymerize, indicating that it is not irreversibly modified or denatured in the reaction. Katanin is a microtubule-stimulated ATPase and requires ATP hydrolysis to sever microtubules. Katanin represents a novel type of enzyme that utilizes energy from nucleotide hydrolysis to break tubulin-tubulin bonds within a microtubule polymer, a process that may aid in disassembling complex microtubule arrays within cells.
真核细胞在细胞周期、分化和细胞迁移过程中会迅速重组其微管细胞骨架。在本研究中，我们纯化了一种异源二聚体蛋白——katanin，它能将微管切断并解聚为微管蛋白二聚体。解聚后的微管蛋白能够重新聚合，这表明它在反应中并未发生不可逆的修饰或变性。katanin是一种受微管刺激的ATP酶，切断微管需要ATP水解。katanin代表了一种新型酶，它利用核苷酸水解产生的能量来断裂微管聚合物内的微管蛋白-微管蛋白键，这一过程可能有助于拆解细胞内复杂的微管阵列。
