Reilein Amy, Nelson W James
Department of Molecular and Cellular Physiology, Beckman Center for Molecular and Genetic Medicine B121, 279 Campus Drive, Stanford University School of Medicine, Stanford, CA 94305-5435, USA.
Nat Cell Biol. 2005 May;7(5):463-73. doi: 10.1038/ncb1248.
A microtubule network on the basal cortex of polarized epithelial cells consists of non-centrosomal microtubules of mixed polarity. Here, we investigate the proteins that are involved in organizing this network, and we show that end-binding protein 1 (EB1), adenomatous polyposis coli protein (APC) and p150Glued - although considered to be microtubule plus-end-binding proteins - are localized along the entire length of microtubules within the network, and at T-junctions between microtubules. The network shows microtubule behaviours that arise from physical interactions between microtubules, including microtubule plus-end stabilization on the sides of other microtubules, and sliding of microtubule ends along other microtubules. APC also localizes to the basal cortex. Microtubules grew over and paused at APC puncta; an in vitro reconstituted microtubule network overlaid APC puncta; and microtubule network reconstitution was inhibited by function-blocking APC antibodies. Thus, APC is a component of a cortical template that guides microtubule network formation.
极化上皮细胞基底皮质上的微管网络由混合极性的非中心体微管组成。在此，我们研究参与组织该网络的蛋白质，并表明端结合蛋白1（EB1）、腺瘤性息肉病大肠杆菌蛋白（APC）和p150Glued——尽管被认为是微管正端结合蛋白——定位于网络内微管的整个长度以及微管之间的T形接头处。该网络显示出由微管之间的物理相互作用产生的微管行为，包括其他微管侧面的微管正端稳定以及微管末端沿其他微管的滑动。APC也定位于基底皮质。微管在APC点上生长并暂停；体外重建的微管网络覆盖了APC点；功能阻断性APC抗体抑制了微管网络的重建。因此，APC是指导微管网络形成的皮质模板的一个组成部分。
