PROTEIN FACTOR ESSENTIAL FOR MICROTUBULE ASSEMBLY
PROTEIN FACTOR ESSENTIAL FOR MICROTUBULE ASSEMBLY
复制标题
DOI：
10.1073/pnas.72.5.1858
复制
发表时间：
1975-01-01
影响因子：
11.1
通讯作者：
KIRSCHNER, MW
中科院分区：
文献类型：
--
作者：
WEINGARTEN, MD;LOCKWOOD, AH;KIRSCHNER, MW
分离到一种微管组装所必需的热稳定蛋白。这种蛋白质，我们命名为tau（tau），与通过重复循环聚合从猪脑纯化的微管蛋白结合存在。通过磷酸纤维素上的离子交换色谱法将Tau与微管蛋白分离。在不存在tau的情况下，微管蛋白完全作为分子量为120，000的两条多肽链（α和β微管蛋白）的6S二聚体存在，其在体外不会组装成微管。添加tau完全恢复了小管形成能力。在非聚合条件下，tau蛋白将6S二聚体转化为36S环结构，这些结构被认为是小管形成的中间体。因此，tau似乎作用于6S微管蛋白二聚体，激活其聚合。tau具有恢复体外微管组装正常特征的独特能力，这使得tau很可能是细胞中微管形成的主要调节因子。
A heat stable protein essentail for microtubule assembly has been isolated. This protein, which we designate tau (tau), is present in association with tubulin purified from porcine brain by repeated cycles of polymerization. Tau is separated from tubulin by ion exchange chromatography on phosphocellulose. In the absence of tau, tubulin exists entirely as a 6S dimer of two polypeptide chains (alpha and beta tubulin) with a molecular weight of 120,000, which will not assemble into microtubules in vitro. Addition of tau completely restores tubule-forming capacity. Under nonpolymerizing conditions, tau converts 6S dimers to 36S rings-structures which have been implicated as intermediates in tubule formation. Hence, tau appears to act on the 6S tubulin dimer, activating it for polymerization. The unique ability of tau to restore the normal features of in vitro microtubule assembly makes it likely that tau is a major regulator of microtubule formation in cells.